1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 19 #include <linux/kernel.h> 20 #include <linux/bio.h> 21 #include <linux/buffer_head.h> 22 #include <linux/file.h> 23 #include <linux/fs.h> 24 #include <linux/pagemap.h> 25 #include <linux/highmem.h> 26 #include <linux/time.h> 27 #include <linux/init.h> 28 #include <linux/string.h> 29 #include <linux/backing-dev.h> 30 #include <linux/mpage.h> 31 #include <linux/swap.h> 32 #include <linux/writeback.h> 33 #include <linux/compat.h> 34 #include <linux/bit_spinlock.h> 35 #include <linux/xattr.h> 36 #include <linux/posix_acl.h> 37 #include <linux/falloc.h> 38 #include <linux/slab.h> 39 #include <linux/ratelimit.h> 40 #include <linux/mount.h> 41 #include <linux/btrfs.h> 42 #include <linux/blkdev.h> 43 #include <linux/posix_acl_xattr.h> 44 #include <linux/uio.h> 45 #include "ctree.h" 46 #include "disk-io.h" 47 #include "transaction.h" 48 #include "btrfs_inode.h" 49 #include "print-tree.h" 50 #include "ordered-data.h" 51 #include "xattr.h" 52 #include "tree-log.h" 53 #include "volumes.h" 54 #include "compression.h" 55 #include "locking.h" 56 #include "free-space-cache.h" 57 #include "inode-map.h" 58 #include "backref.h" 59 #include "hash.h" 60 #include "props.h" 61 #include "qgroup.h" 62 #include "dedupe.h" 63 64 struct btrfs_iget_args { 65 struct btrfs_key *location; 66 struct btrfs_root *root; 67 }; 68 69 struct btrfs_dio_data { 70 u64 outstanding_extents; 71 u64 reserve; 72 u64 unsubmitted_oe_range_start; 73 u64 unsubmitted_oe_range_end; 74 int overwrite; 75 }; 76 77 static const struct inode_operations btrfs_dir_inode_operations; 78 static const struct inode_operations btrfs_symlink_inode_operations; 79 static const struct inode_operations btrfs_dir_ro_inode_operations; 80 static const struct inode_operations btrfs_special_inode_operations; 81 static const struct inode_operations btrfs_file_inode_operations; 82 static const struct address_space_operations btrfs_aops; 83 static const struct address_space_operations btrfs_symlink_aops; 84 static const struct file_operations btrfs_dir_file_operations; 85 static const struct extent_io_ops btrfs_extent_io_ops; 86 87 static struct kmem_cache *btrfs_inode_cachep; 88 struct kmem_cache *btrfs_trans_handle_cachep; 89 struct kmem_cache *btrfs_path_cachep; 90 struct kmem_cache *btrfs_free_space_cachep; 91 92 #define S_SHIFT 12 93 static const unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = { 94 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE, 95 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR, 96 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV, 97 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV, 98 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO, 99 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK, 100 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK, 101 }; 102 103 static int btrfs_setsize(struct inode *inode, struct iattr *attr); 104 static int btrfs_truncate(struct inode *inode); 105 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent); 106 static noinline int cow_file_range(struct inode *inode, 107 struct page *locked_page, 108 u64 start, u64 end, u64 delalloc_end, 109 int *page_started, unsigned long *nr_written, 110 int unlock, struct btrfs_dedupe_hash *hash); 111 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len, 112 u64 orig_start, u64 block_start, 113 u64 block_len, u64 orig_block_len, 114 u64 ram_bytes, int compress_type, 115 int type); 116 117 static void __endio_write_update_ordered(struct inode *inode, 118 const u64 offset, const u64 bytes, 119 const bool uptodate); 120 121 /* 122 * Cleanup all submitted ordered extents in specified range to handle errors 123 * from the fill_dellaloc() callback. 124 * 125 * NOTE: caller must ensure that when an error happens, it can not call 126 * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING 127 * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata 128 * to be released, which we want to happen only when finishing the ordered 129 * extent (btrfs_finish_ordered_io()). Also note that the caller of the 130 * fill_delalloc() callback already does proper cleanup for the first page of 131 * the range, that is, it invokes the callback writepage_end_io_hook() for the 132 * range of the first page. 133 */ 134 static inline void btrfs_cleanup_ordered_extents(struct inode *inode, 135 const u64 offset, 136 const u64 bytes) 137 { 138 return __endio_write_update_ordered(inode, offset + PAGE_SIZE, 139 bytes - PAGE_SIZE, false); 140 } 141 142 static int btrfs_dirty_inode(struct inode *inode); 143 144 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 145 void btrfs_test_inode_set_ops(struct inode *inode) 146 { 147 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 148 } 149 #endif 150 151 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, 152 struct inode *inode, struct inode *dir, 153 const struct qstr *qstr) 154 { 155 int err; 156 157 err = btrfs_init_acl(trans, inode, dir); 158 if (!err) 159 err = btrfs_xattr_security_init(trans, inode, dir, qstr); 160 return err; 161 } 162 163 /* 164 * this does all the hard work for inserting an inline extent into 165 * the btree. The caller should have done a btrfs_drop_extents so that 166 * no overlapping inline items exist in the btree 167 */ 168 static int insert_inline_extent(struct btrfs_trans_handle *trans, 169 struct btrfs_path *path, int extent_inserted, 170 struct btrfs_root *root, struct inode *inode, 171 u64 start, size_t size, size_t compressed_size, 172 int compress_type, 173 struct page **compressed_pages) 174 { 175 struct extent_buffer *leaf; 176 struct page *page = NULL; 177 char *kaddr; 178 unsigned long ptr; 179 struct btrfs_file_extent_item *ei; 180 int ret; 181 size_t cur_size = size; 182 unsigned long offset; 183 184 if (compressed_size && compressed_pages) 185 cur_size = compressed_size; 186 187 inode_add_bytes(inode, size); 188 189 if (!extent_inserted) { 190 struct btrfs_key key; 191 size_t datasize; 192 193 key.objectid = btrfs_ino(BTRFS_I(inode)); 194 key.offset = start; 195 key.type = BTRFS_EXTENT_DATA_KEY; 196 197 datasize = btrfs_file_extent_calc_inline_size(cur_size); 198 path->leave_spinning = 1; 199 ret = btrfs_insert_empty_item(trans, root, path, &key, 200 datasize); 201 if (ret) 202 goto fail; 203 } 204 leaf = path->nodes[0]; 205 ei = btrfs_item_ptr(leaf, path->slots[0], 206 struct btrfs_file_extent_item); 207 btrfs_set_file_extent_generation(leaf, ei, trans->transid); 208 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); 209 btrfs_set_file_extent_encryption(leaf, ei, 0); 210 btrfs_set_file_extent_other_encoding(leaf, ei, 0); 211 btrfs_set_file_extent_ram_bytes(leaf, ei, size); 212 ptr = btrfs_file_extent_inline_start(ei); 213 214 if (compress_type != BTRFS_COMPRESS_NONE) { 215 struct page *cpage; 216 int i = 0; 217 while (compressed_size > 0) { 218 cpage = compressed_pages[i]; 219 cur_size = min_t(unsigned long, compressed_size, 220 PAGE_SIZE); 221 222 kaddr = kmap_atomic(cpage); 223 write_extent_buffer(leaf, kaddr, ptr, cur_size); 224 kunmap_atomic(kaddr); 225 226 i++; 227 ptr += cur_size; 228 compressed_size -= cur_size; 229 } 230 btrfs_set_file_extent_compression(leaf, ei, 231 compress_type); 232 } else { 233 page = find_get_page(inode->i_mapping, 234 start >> PAGE_SHIFT); 235 btrfs_set_file_extent_compression(leaf, ei, 0); 236 kaddr = kmap_atomic(page); 237 offset = start & (PAGE_SIZE - 1); 238 write_extent_buffer(leaf, kaddr + offset, ptr, size); 239 kunmap_atomic(kaddr); 240 put_page(page); 241 } 242 btrfs_mark_buffer_dirty(leaf); 243 btrfs_release_path(path); 244 245 /* 246 * we're an inline extent, so nobody can 247 * extend the file past i_size without locking 248 * a page we already have locked. 249 * 250 * We must do any isize and inode updates 251 * before we unlock the pages. Otherwise we 252 * could end up racing with unlink. 253 */ 254 BTRFS_I(inode)->disk_i_size = inode->i_size; 255 ret = btrfs_update_inode(trans, root, inode); 256 257 fail: 258 return ret; 259 } 260 261 262 /* 263 * conditionally insert an inline extent into the file. This 264 * does the checks required to make sure the data is small enough 265 * to fit as an inline extent. 266 */ 267 static noinline int cow_file_range_inline(struct btrfs_root *root, 268 struct inode *inode, u64 start, 269 u64 end, size_t compressed_size, 270 int compress_type, 271 struct page **compressed_pages) 272 { 273 struct btrfs_fs_info *fs_info = root->fs_info; 274 struct btrfs_trans_handle *trans; 275 u64 isize = i_size_read(inode); 276 u64 actual_end = min(end + 1, isize); 277 u64 inline_len = actual_end - start; 278 u64 aligned_end = ALIGN(end, fs_info->sectorsize); 279 u64 data_len = inline_len; 280 int ret; 281 struct btrfs_path *path; 282 int extent_inserted = 0; 283 u32 extent_item_size; 284 285 if (compressed_size) 286 data_len = compressed_size; 287 288 if (start > 0 || 289 actual_end > fs_info->sectorsize || 290 data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) || 291 (!compressed_size && 292 (actual_end & (fs_info->sectorsize - 1)) == 0) || 293 end + 1 < isize || 294 data_len > fs_info->max_inline) { 295 return 1; 296 } 297 298 path = btrfs_alloc_path(); 299 if (!path) 300 return -ENOMEM; 301 302 trans = btrfs_join_transaction(root); 303 if (IS_ERR(trans)) { 304 btrfs_free_path(path); 305 return PTR_ERR(trans); 306 } 307 trans->block_rsv = &fs_info->delalloc_block_rsv; 308 309 if (compressed_size && compressed_pages) 310 extent_item_size = btrfs_file_extent_calc_inline_size( 311 compressed_size); 312 else 313 extent_item_size = btrfs_file_extent_calc_inline_size( 314 inline_len); 315 316 ret = __btrfs_drop_extents(trans, root, inode, path, 317 start, aligned_end, NULL, 318 1, 1, extent_item_size, &extent_inserted); 319 if (ret) { 320 btrfs_abort_transaction(trans, ret); 321 goto out; 322 } 323 324 if (isize > actual_end) 325 inline_len = min_t(u64, isize, actual_end); 326 ret = insert_inline_extent(trans, path, extent_inserted, 327 root, inode, start, 328 inline_len, compressed_size, 329 compress_type, compressed_pages); 330 if (ret && ret != -ENOSPC) { 331 btrfs_abort_transaction(trans, ret); 332 goto out; 333 } else if (ret == -ENOSPC) { 334 ret = 1; 335 goto out; 336 } 337 338 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 339 btrfs_delalloc_release_metadata(BTRFS_I(inode), end + 1 - start); 340 btrfs_drop_extent_cache(BTRFS_I(inode), start, aligned_end - 1, 0); 341 out: 342 /* 343 * Don't forget to free the reserved space, as for inlined extent 344 * it won't count as data extent, free them directly here. 345 * And at reserve time, it's always aligned to page size, so 346 * just free one page here. 347 */ 348 btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE); 349 btrfs_free_path(path); 350 btrfs_end_transaction(trans); 351 return ret; 352 } 353 354 struct async_extent { 355 u64 start; 356 u64 ram_size; 357 u64 compressed_size; 358 struct page **pages; 359 unsigned long nr_pages; 360 int compress_type; 361 struct list_head list; 362 }; 363 364 struct async_cow { 365 struct inode *inode; 366 struct btrfs_root *root; 367 struct page *locked_page; 368 u64 start; 369 u64 end; 370 struct list_head extents; 371 struct btrfs_work work; 372 }; 373 374 static noinline int add_async_extent(struct async_cow *cow, 375 u64 start, u64 ram_size, 376 u64 compressed_size, 377 struct page **pages, 378 unsigned long nr_pages, 379 int compress_type) 380 { 381 struct async_extent *async_extent; 382 383 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); 384 BUG_ON(!async_extent); /* -ENOMEM */ 385 async_extent->start = start; 386 async_extent->ram_size = ram_size; 387 async_extent->compressed_size = compressed_size; 388 async_extent->pages = pages; 389 async_extent->nr_pages = nr_pages; 390 async_extent->compress_type = compress_type; 391 list_add_tail(&async_extent->list, &cow->extents); 392 return 0; 393 } 394 395 static inline int inode_need_compress(struct inode *inode) 396 { 397 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 398 399 /* force compress */ 400 if (btrfs_test_opt(fs_info, FORCE_COMPRESS)) 401 return 1; 402 /* bad compression ratios */ 403 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) 404 return 0; 405 if (btrfs_test_opt(fs_info, COMPRESS) || 406 BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS || 407 BTRFS_I(inode)->force_compress) 408 return 1; 409 return 0; 410 } 411 412 static inline void inode_should_defrag(struct btrfs_inode *inode, 413 u64 start, u64 end, u64 num_bytes, u64 small_write) 414 { 415 /* If this is a small write inside eof, kick off a defrag */ 416 if (num_bytes < small_write && 417 (start > 0 || end + 1 < inode->disk_i_size)) 418 btrfs_add_inode_defrag(NULL, inode); 419 } 420 421 /* 422 * we create compressed extents in two phases. The first 423 * phase compresses a range of pages that have already been 424 * locked (both pages and state bits are locked). 425 * 426 * This is done inside an ordered work queue, and the compression 427 * is spread across many cpus. The actual IO submission is step 428 * two, and the ordered work queue takes care of making sure that 429 * happens in the same order things were put onto the queue by 430 * writepages and friends. 431 * 432 * If this code finds it can't get good compression, it puts an 433 * entry onto the work queue to write the uncompressed bytes. This 434 * makes sure that both compressed inodes and uncompressed inodes 435 * are written in the same order that the flusher thread sent them 436 * down. 437 */ 438 static noinline void compress_file_range(struct inode *inode, 439 struct page *locked_page, 440 u64 start, u64 end, 441 struct async_cow *async_cow, 442 int *num_added) 443 { 444 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 445 struct btrfs_root *root = BTRFS_I(inode)->root; 446 u64 num_bytes; 447 u64 blocksize = fs_info->sectorsize; 448 u64 actual_end; 449 u64 isize = i_size_read(inode); 450 int ret = 0; 451 struct page **pages = NULL; 452 unsigned long nr_pages; 453 unsigned long total_compressed = 0; 454 unsigned long total_in = 0; 455 int i; 456 int will_compress; 457 int compress_type = fs_info->compress_type; 458 int redirty = 0; 459 460 inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1, 461 SZ_16K); 462 463 actual_end = min_t(u64, isize, end + 1); 464 again: 465 will_compress = 0; 466 nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; 467 BUILD_BUG_ON((BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0); 468 nr_pages = min_t(unsigned long, nr_pages, 469 BTRFS_MAX_COMPRESSED / PAGE_SIZE); 470 471 /* 472 * we don't want to send crud past the end of i_size through 473 * compression, that's just a waste of CPU time. So, if the 474 * end of the file is before the start of our current 475 * requested range of bytes, we bail out to the uncompressed 476 * cleanup code that can deal with all of this. 477 * 478 * It isn't really the fastest way to fix things, but this is a 479 * very uncommon corner. 480 */ 481 if (actual_end <= start) 482 goto cleanup_and_bail_uncompressed; 483 484 total_compressed = actual_end - start; 485 486 /* 487 * skip compression for a small file range(<=blocksize) that 488 * isn't an inline extent, since it doesn't save disk space at all. 489 */ 490 if (total_compressed <= blocksize && 491 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) 492 goto cleanup_and_bail_uncompressed; 493 494 total_compressed = min_t(unsigned long, total_compressed, 495 BTRFS_MAX_UNCOMPRESSED); 496 num_bytes = ALIGN(end - start + 1, blocksize); 497 num_bytes = max(blocksize, num_bytes); 498 total_in = 0; 499 ret = 0; 500 501 /* 502 * we do compression for mount -o compress and when the 503 * inode has not been flagged as nocompress. This flag can 504 * change at any time if we discover bad compression ratios. 505 */ 506 if (inode_need_compress(inode)) { 507 WARN_ON(pages); 508 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); 509 if (!pages) { 510 /* just bail out to the uncompressed code */ 511 goto cont; 512 } 513 514 if (BTRFS_I(inode)->force_compress) 515 compress_type = BTRFS_I(inode)->force_compress; 516 517 /* 518 * we need to call clear_page_dirty_for_io on each 519 * page in the range. Otherwise applications with the file 520 * mmap'd can wander in and change the page contents while 521 * we are compressing them. 522 * 523 * If the compression fails for any reason, we set the pages 524 * dirty again later on. 525 */ 526 extent_range_clear_dirty_for_io(inode, start, end); 527 redirty = 1; 528 ret = btrfs_compress_pages(compress_type, 529 inode->i_mapping, start, 530 pages, 531 &nr_pages, 532 &total_in, 533 &total_compressed); 534 535 if (!ret) { 536 unsigned long offset = total_compressed & 537 (PAGE_SIZE - 1); 538 struct page *page = pages[nr_pages - 1]; 539 char *kaddr; 540 541 /* zero the tail end of the last page, we might be 542 * sending it down to disk 543 */ 544 if (offset) { 545 kaddr = kmap_atomic(page); 546 memset(kaddr + offset, 0, 547 PAGE_SIZE - offset); 548 kunmap_atomic(kaddr); 549 } 550 will_compress = 1; 551 } 552 } 553 cont: 554 if (start == 0) { 555 /* lets try to make an inline extent */ 556 if (ret || total_in < (actual_end - start)) { 557 /* we didn't compress the entire range, try 558 * to make an uncompressed inline extent. 559 */ 560 ret = cow_file_range_inline(root, inode, start, end, 561 0, BTRFS_COMPRESS_NONE, NULL); 562 } else { 563 /* try making a compressed inline extent */ 564 ret = cow_file_range_inline(root, inode, start, end, 565 total_compressed, 566 compress_type, pages); 567 } 568 if (ret <= 0) { 569 unsigned long clear_flags = EXTENT_DELALLOC | 570 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG; 571 unsigned long page_error_op; 572 573 clear_flags |= (ret < 0) ? EXTENT_DO_ACCOUNTING : 0; 574 page_error_op = ret < 0 ? PAGE_SET_ERROR : 0; 575 576 /* 577 * inline extent creation worked or returned error, 578 * we don't need to create any more async work items. 579 * Unlock and free up our temp pages. 580 */ 581 extent_clear_unlock_delalloc(inode, start, end, end, 582 NULL, clear_flags, 583 PAGE_UNLOCK | 584 PAGE_CLEAR_DIRTY | 585 PAGE_SET_WRITEBACK | 586 page_error_op | 587 PAGE_END_WRITEBACK); 588 if (ret == 0) 589 btrfs_free_reserved_data_space_noquota(inode, 590 start, 591 end - start + 1); 592 goto free_pages_out; 593 } 594 } 595 596 if (will_compress) { 597 /* 598 * we aren't doing an inline extent round the compressed size 599 * up to a block size boundary so the allocator does sane 600 * things 601 */ 602 total_compressed = ALIGN(total_compressed, blocksize); 603 604 /* 605 * one last check to make sure the compression is really a 606 * win, compare the page count read with the blocks on disk, 607 * compression must free at least one sector size 608 */ 609 total_in = ALIGN(total_in, PAGE_SIZE); 610 if (total_compressed + blocksize <= total_in) { 611 num_bytes = total_in; 612 *num_added += 1; 613 614 /* 615 * The async work queues will take care of doing actual 616 * allocation on disk for these compressed pages, and 617 * will submit them to the elevator. 618 */ 619 add_async_extent(async_cow, start, num_bytes, 620 total_compressed, pages, nr_pages, 621 compress_type); 622 623 if (start + num_bytes < end) { 624 start += num_bytes; 625 pages = NULL; 626 cond_resched(); 627 goto again; 628 } 629 return; 630 } 631 } 632 if (pages) { 633 /* 634 * the compression code ran but failed to make things smaller, 635 * free any pages it allocated and our page pointer array 636 */ 637 for (i = 0; i < nr_pages; i++) { 638 WARN_ON(pages[i]->mapping); 639 put_page(pages[i]); 640 } 641 kfree(pages); 642 pages = NULL; 643 total_compressed = 0; 644 nr_pages = 0; 645 646 /* flag the file so we don't compress in the future */ 647 if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) && 648 !(BTRFS_I(inode)->force_compress)) { 649 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; 650 } 651 } 652 cleanup_and_bail_uncompressed: 653 /* 654 * No compression, but we still need to write the pages in the file 655 * we've been given so far. redirty the locked page if it corresponds 656 * to our extent and set things up for the async work queue to run 657 * cow_file_range to do the normal delalloc dance. 658 */ 659 if (page_offset(locked_page) >= start && 660 page_offset(locked_page) <= end) 661 __set_page_dirty_nobuffers(locked_page); 662 /* unlocked later on in the async handlers */ 663 664 if (redirty) 665 extent_range_redirty_for_io(inode, start, end); 666 add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0, 667 BTRFS_COMPRESS_NONE); 668 *num_added += 1; 669 670 return; 671 672 free_pages_out: 673 for (i = 0; i < nr_pages; i++) { 674 WARN_ON(pages[i]->mapping); 675 put_page(pages[i]); 676 } 677 kfree(pages); 678 } 679 680 static void free_async_extent_pages(struct async_extent *async_extent) 681 { 682 int i; 683 684 if (!async_extent->pages) 685 return; 686 687 for (i = 0; i < async_extent->nr_pages; i++) { 688 WARN_ON(async_extent->pages[i]->mapping); 689 put_page(async_extent->pages[i]); 690 } 691 kfree(async_extent->pages); 692 async_extent->nr_pages = 0; 693 async_extent->pages = NULL; 694 } 695 696 /* 697 * phase two of compressed writeback. This is the ordered portion 698 * of the code, which only gets called in the order the work was 699 * queued. We walk all the async extents created by compress_file_range 700 * and send them down to the disk. 701 */ 702 static noinline void submit_compressed_extents(struct inode *inode, 703 struct async_cow *async_cow) 704 { 705 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 706 struct async_extent *async_extent; 707 u64 alloc_hint = 0; 708 struct btrfs_key ins; 709 struct extent_map *em; 710 struct btrfs_root *root = BTRFS_I(inode)->root; 711 struct extent_io_tree *io_tree; 712 int ret = 0; 713 714 again: 715 while (!list_empty(&async_cow->extents)) { 716 async_extent = list_entry(async_cow->extents.next, 717 struct async_extent, list); 718 list_del(&async_extent->list); 719 720 io_tree = &BTRFS_I(inode)->io_tree; 721 722 retry: 723 /* did the compression code fall back to uncompressed IO? */ 724 if (!async_extent->pages) { 725 int page_started = 0; 726 unsigned long nr_written = 0; 727 728 lock_extent(io_tree, async_extent->start, 729 async_extent->start + 730 async_extent->ram_size - 1); 731 732 /* allocate blocks */ 733 ret = cow_file_range(inode, async_cow->locked_page, 734 async_extent->start, 735 async_extent->start + 736 async_extent->ram_size - 1, 737 async_extent->start + 738 async_extent->ram_size - 1, 739 &page_started, &nr_written, 0, 740 NULL); 741 742 /* JDM XXX */ 743 744 /* 745 * if page_started, cow_file_range inserted an 746 * inline extent and took care of all the unlocking 747 * and IO for us. Otherwise, we need to submit 748 * all those pages down to the drive. 749 */ 750 if (!page_started && !ret) 751 extent_write_locked_range(io_tree, 752 inode, async_extent->start, 753 async_extent->start + 754 async_extent->ram_size - 1, 755 btrfs_get_extent, 756 WB_SYNC_ALL); 757 else if (ret) 758 unlock_page(async_cow->locked_page); 759 kfree(async_extent); 760 cond_resched(); 761 continue; 762 } 763 764 lock_extent(io_tree, async_extent->start, 765 async_extent->start + async_extent->ram_size - 1); 766 767 ret = btrfs_reserve_extent(root, async_extent->ram_size, 768 async_extent->compressed_size, 769 async_extent->compressed_size, 770 0, alloc_hint, &ins, 1, 1); 771 if (ret) { 772 free_async_extent_pages(async_extent); 773 774 if (ret == -ENOSPC) { 775 unlock_extent(io_tree, async_extent->start, 776 async_extent->start + 777 async_extent->ram_size - 1); 778 779 /* 780 * we need to redirty the pages if we decide to 781 * fallback to uncompressed IO, otherwise we 782 * will not submit these pages down to lower 783 * layers. 784 */ 785 extent_range_redirty_for_io(inode, 786 async_extent->start, 787 async_extent->start + 788 async_extent->ram_size - 1); 789 790 goto retry; 791 } 792 goto out_free; 793 } 794 /* 795 * here we're doing allocation and writeback of the 796 * compressed pages 797 */ 798 em = create_io_em(inode, async_extent->start, 799 async_extent->ram_size, /* len */ 800 async_extent->start, /* orig_start */ 801 ins.objectid, /* block_start */ 802 ins.offset, /* block_len */ 803 ins.offset, /* orig_block_len */ 804 async_extent->ram_size, /* ram_bytes */ 805 async_extent->compress_type, 806 BTRFS_ORDERED_COMPRESSED); 807 if (IS_ERR(em)) 808 /* ret value is not necessary due to void function */ 809 goto out_free_reserve; 810 free_extent_map(em); 811 812 ret = btrfs_add_ordered_extent_compress(inode, 813 async_extent->start, 814 ins.objectid, 815 async_extent->ram_size, 816 ins.offset, 817 BTRFS_ORDERED_COMPRESSED, 818 async_extent->compress_type); 819 if (ret) { 820 btrfs_drop_extent_cache(BTRFS_I(inode), 821 async_extent->start, 822 async_extent->start + 823 async_extent->ram_size - 1, 0); 824 goto out_free_reserve; 825 } 826 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 827 828 /* 829 * clear dirty, set writeback and unlock the pages. 830 */ 831 extent_clear_unlock_delalloc(inode, async_extent->start, 832 async_extent->start + 833 async_extent->ram_size - 1, 834 async_extent->start + 835 async_extent->ram_size - 1, 836 NULL, EXTENT_LOCKED | EXTENT_DELALLOC, 837 PAGE_UNLOCK | PAGE_CLEAR_DIRTY | 838 PAGE_SET_WRITEBACK); 839 if (btrfs_submit_compressed_write(inode, 840 async_extent->start, 841 async_extent->ram_size, 842 ins.objectid, 843 ins.offset, async_extent->pages, 844 async_extent->nr_pages)) { 845 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; 846 struct page *p = async_extent->pages[0]; 847 const u64 start = async_extent->start; 848 const u64 end = start + async_extent->ram_size - 1; 849 850 p->mapping = inode->i_mapping; 851 tree->ops->writepage_end_io_hook(p, start, end, 852 NULL, 0); 853 p->mapping = NULL; 854 extent_clear_unlock_delalloc(inode, start, end, end, 855 NULL, 0, 856 PAGE_END_WRITEBACK | 857 PAGE_SET_ERROR); 858 free_async_extent_pages(async_extent); 859 } 860 alloc_hint = ins.objectid + ins.offset; 861 kfree(async_extent); 862 cond_resched(); 863 } 864 return; 865 out_free_reserve: 866 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 867 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); 868 out_free: 869 extent_clear_unlock_delalloc(inode, async_extent->start, 870 async_extent->start + 871 async_extent->ram_size - 1, 872 async_extent->start + 873 async_extent->ram_size - 1, 874 NULL, EXTENT_LOCKED | EXTENT_DELALLOC | 875 EXTENT_DELALLOC_NEW | 876 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, 877 PAGE_UNLOCK | PAGE_CLEAR_DIRTY | 878 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK | 879 PAGE_SET_ERROR); 880 free_async_extent_pages(async_extent); 881 kfree(async_extent); 882 goto again; 883 } 884 885 static u64 get_extent_allocation_hint(struct inode *inode, u64 start, 886 u64 num_bytes) 887 { 888 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 889 struct extent_map *em; 890 u64 alloc_hint = 0; 891 892 read_lock(&em_tree->lock); 893 em = search_extent_mapping(em_tree, start, num_bytes); 894 if (em) { 895 /* 896 * if block start isn't an actual block number then find the 897 * first block in this inode and use that as a hint. If that 898 * block is also bogus then just don't worry about it. 899 */ 900 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 901 free_extent_map(em); 902 em = search_extent_mapping(em_tree, 0, 0); 903 if (em && em->block_start < EXTENT_MAP_LAST_BYTE) 904 alloc_hint = em->block_start; 905 if (em) 906 free_extent_map(em); 907 } else { 908 alloc_hint = em->block_start; 909 free_extent_map(em); 910 } 911 } 912 read_unlock(&em_tree->lock); 913 914 return alloc_hint; 915 } 916 917 /* 918 * when extent_io.c finds a delayed allocation range in the file, 919 * the call backs end up in this code. The basic idea is to 920 * allocate extents on disk for the range, and create ordered data structs 921 * in ram to track those extents. 922 * 923 * locked_page is the page that writepage had locked already. We use 924 * it to make sure we don't do extra locks or unlocks. 925 * 926 * *page_started is set to one if we unlock locked_page and do everything 927 * required to start IO on it. It may be clean and already done with 928 * IO when we return. 929 */ 930 static noinline int cow_file_range(struct inode *inode, 931 struct page *locked_page, 932 u64 start, u64 end, u64 delalloc_end, 933 int *page_started, unsigned long *nr_written, 934 int unlock, struct btrfs_dedupe_hash *hash) 935 { 936 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 937 struct btrfs_root *root = BTRFS_I(inode)->root; 938 u64 alloc_hint = 0; 939 u64 num_bytes; 940 unsigned long ram_size; 941 u64 disk_num_bytes; 942 u64 cur_alloc_size = 0; 943 u64 blocksize = fs_info->sectorsize; 944 struct btrfs_key ins; 945 struct extent_map *em; 946 unsigned clear_bits; 947 unsigned long page_ops; 948 bool extent_reserved = false; 949 int ret = 0; 950 951 if (btrfs_is_free_space_inode(BTRFS_I(inode))) { 952 WARN_ON_ONCE(1); 953 ret = -EINVAL; 954 goto out_unlock; 955 } 956 957 num_bytes = ALIGN(end - start + 1, blocksize); 958 num_bytes = max(blocksize, num_bytes); 959 disk_num_bytes = num_bytes; 960 961 inode_should_defrag(BTRFS_I(inode), start, end, num_bytes, SZ_64K); 962 963 if (start == 0) { 964 /* lets try to make an inline extent */ 965 ret = cow_file_range_inline(root, inode, start, end, 0, 966 BTRFS_COMPRESS_NONE, NULL); 967 if (ret == 0) { 968 extent_clear_unlock_delalloc(inode, start, end, 969 delalloc_end, NULL, 970 EXTENT_LOCKED | EXTENT_DELALLOC | 971 EXTENT_DELALLOC_NEW | 972 EXTENT_DEFRAG, PAGE_UNLOCK | 973 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | 974 PAGE_END_WRITEBACK); 975 btrfs_free_reserved_data_space_noquota(inode, start, 976 end - start + 1); 977 *nr_written = *nr_written + 978 (end - start + PAGE_SIZE) / PAGE_SIZE; 979 *page_started = 1; 980 goto out; 981 } else if (ret < 0) { 982 goto out_unlock; 983 } 984 } 985 986 BUG_ON(disk_num_bytes > 987 btrfs_super_total_bytes(fs_info->super_copy)); 988 989 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); 990 btrfs_drop_extent_cache(BTRFS_I(inode), start, 991 start + num_bytes - 1, 0); 992 993 while (disk_num_bytes > 0) { 994 cur_alloc_size = disk_num_bytes; 995 ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size, 996 fs_info->sectorsize, 0, alloc_hint, 997 &ins, 1, 1); 998 if (ret < 0) 999 goto out_unlock; 1000 cur_alloc_size = ins.offset; 1001 extent_reserved = true; 1002 1003 ram_size = ins.offset; 1004 em = create_io_em(inode, start, ins.offset, /* len */ 1005 start, /* orig_start */ 1006 ins.objectid, /* block_start */ 1007 ins.offset, /* block_len */ 1008 ins.offset, /* orig_block_len */ 1009 ram_size, /* ram_bytes */ 1010 BTRFS_COMPRESS_NONE, /* compress_type */ 1011 BTRFS_ORDERED_REGULAR /* type */); 1012 if (IS_ERR(em)) 1013 goto out_reserve; 1014 free_extent_map(em); 1015 1016 ret = btrfs_add_ordered_extent(inode, start, ins.objectid, 1017 ram_size, cur_alloc_size, 0); 1018 if (ret) 1019 goto out_drop_extent_cache; 1020 1021 if (root->root_key.objectid == 1022 BTRFS_DATA_RELOC_TREE_OBJECTID) { 1023 ret = btrfs_reloc_clone_csums(inode, start, 1024 cur_alloc_size); 1025 /* 1026 * Only drop cache here, and process as normal. 1027 * 1028 * We must not allow extent_clear_unlock_delalloc() 1029 * at out_unlock label to free meta of this ordered 1030 * extent, as its meta should be freed by 1031 * btrfs_finish_ordered_io(). 1032 * 1033 * So we must continue until @start is increased to 1034 * skip current ordered extent. 1035 */ 1036 if (ret) 1037 btrfs_drop_extent_cache(BTRFS_I(inode), start, 1038 start + ram_size - 1, 0); 1039 } 1040 1041 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 1042 1043 /* we're not doing compressed IO, don't unlock the first 1044 * page (which the caller expects to stay locked), don't 1045 * clear any dirty bits and don't set any writeback bits 1046 * 1047 * Do set the Private2 bit so we know this page was properly 1048 * setup for writepage 1049 */ 1050 page_ops = unlock ? PAGE_UNLOCK : 0; 1051 page_ops |= PAGE_SET_PRIVATE2; 1052 1053 extent_clear_unlock_delalloc(inode, start, 1054 start + ram_size - 1, 1055 delalloc_end, locked_page, 1056 EXTENT_LOCKED | EXTENT_DELALLOC, 1057 page_ops); 1058 if (disk_num_bytes < cur_alloc_size) 1059 disk_num_bytes = 0; 1060 else 1061 disk_num_bytes -= cur_alloc_size; 1062 num_bytes -= cur_alloc_size; 1063 alloc_hint = ins.objectid + ins.offset; 1064 start += cur_alloc_size; 1065 extent_reserved = false; 1066 1067 /* 1068 * btrfs_reloc_clone_csums() error, since start is increased 1069 * extent_clear_unlock_delalloc() at out_unlock label won't 1070 * free metadata of current ordered extent, we're OK to exit. 1071 */ 1072 if (ret) 1073 goto out_unlock; 1074 } 1075 out: 1076 return ret; 1077 1078 out_drop_extent_cache: 1079 btrfs_drop_extent_cache(BTRFS_I(inode), start, start + ram_size - 1, 0); 1080 out_reserve: 1081 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 1082 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); 1083 out_unlock: 1084 clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | 1085 EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV; 1086 page_ops = PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | 1087 PAGE_END_WRITEBACK; 1088 /* 1089 * If we reserved an extent for our delalloc range (or a subrange) and 1090 * failed to create the respective ordered extent, then it means that 1091 * when we reserved the extent we decremented the extent's size from 1092 * the data space_info's bytes_may_use counter and incremented the 1093 * space_info's bytes_reserved counter by the same amount. We must make 1094 * sure extent_clear_unlock_delalloc() does not try to decrement again 1095 * the data space_info's bytes_may_use counter, therefore we do not pass 1096 * it the flag EXTENT_CLEAR_DATA_RESV. 1097 */ 1098 if (extent_reserved) { 1099 extent_clear_unlock_delalloc(inode, start, 1100 start + cur_alloc_size, 1101 start + cur_alloc_size, 1102 locked_page, 1103 clear_bits, 1104 page_ops); 1105 start += cur_alloc_size; 1106 if (start >= end) 1107 goto out; 1108 } 1109 extent_clear_unlock_delalloc(inode, start, end, delalloc_end, 1110 locked_page, 1111 clear_bits | EXTENT_CLEAR_DATA_RESV, 1112 page_ops); 1113 goto out; 1114 } 1115 1116 /* 1117 * work queue call back to started compression on a file and pages 1118 */ 1119 static noinline void async_cow_start(struct btrfs_work *work) 1120 { 1121 struct async_cow *async_cow; 1122 int num_added = 0; 1123 async_cow = container_of(work, struct async_cow, work); 1124 1125 compress_file_range(async_cow->inode, async_cow->locked_page, 1126 async_cow->start, async_cow->end, async_cow, 1127 &num_added); 1128 if (num_added == 0) { 1129 btrfs_add_delayed_iput(async_cow->inode); 1130 async_cow->inode = NULL; 1131 } 1132 } 1133 1134 /* 1135 * work queue call back to submit previously compressed pages 1136 */ 1137 static noinline void async_cow_submit(struct btrfs_work *work) 1138 { 1139 struct btrfs_fs_info *fs_info; 1140 struct async_cow *async_cow; 1141 struct btrfs_root *root; 1142 unsigned long nr_pages; 1143 1144 async_cow = container_of(work, struct async_cow, work); 1145 1146 root = async_cow->root; 1147 fs_info = root->fs_info; 1148 nr_pages = (async_cow->end - async_cow->start + PAGE_SIZE) >> 1149 PAGE_SHIFT; 1150 1151 /* 1152 * atomic_sub_return implies a barrier for waitqueue_active 1153 */ 1154 if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) < 1155 5 * SZ_1M && 1156 waitqueue_active(&fs_info->async_submit_wait)) 1157 wake_up(&fs_info->async_submit_wait); 1158 1159 if (async_cow->inode) 1160 submit_compressed_extents(async_cow->inode, async_cow); 1161 } 1162 1163 static noinline void async_cow_free(struct btrfs_work *work) 1164 { 1165 struct async_cow *async_cow; 1166 async_cow = container_of(work, struct async_cow, work); 1167 if (async_cow->inode) 1168 btrfs_add_delayed_iput(async_cow->inode); 1169 kfree(async_cow); 1170 } 1171 1172 static int cow_file_range_async(struct inode *inode, struct page *locked_page, 1173 u64 start, u64 end, int *page_started, 1174 unsigned long *nr_written) 1175 { 1176 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1177 struct async_cow *async_cow; 1178 struct btrfs_root *root = BTRFS_I(inode)->root; 1179 unsigned long nr_pages; 1180 u64 cur_end; 1181 1182 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED, 1183 1, 0, NULL, GFP_NOFS); 1184 while (start < end) { 1185 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); 1186 BUG_ON(!async_cow); /* -ENOMEM */ 1187 async_cow->inode = igrab(inode); 1188 async_cow->root = root; 1189 async_cow->locked_page = locked_page; 1190 async_cow->start = start; 1191 1192 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS && 1193 !btrfs_test_opt(fs_info, FORCE_COMPRESS)) 1194 cur_end = end; 1195 else 1196 cur_end = min(end, start + SZ_512K - 1); 1197 1198 async_cow->end = cur_end; 1199 INIT_LIST_HEAD(&async_cow->extents); 1200 1201 btrfs_init_work(&async_cow->work, 1202 btrfs_delalloc_helper, 1203 async_cow_start, async_cow_submit, 1204 async_cow_free); 1205 1206 nr_pages = (cur_end - start + PAGE_SIZE) >> 1207 PAGE_SHIFT; 1208 atomic_add(nr_pages, &fs_info->async_delalloc_pages); 1209 1210 btrfs_queue_work(fs_info->delalloc_workers, &async_cow->work); 1211 1212 while (atomic_read(&fs_info->async_submit_draining) && 1213 atomic_read(&fs_info->async_delalloc_pages)) { 1214 wait_event(fs_info->async_submit_wait, 1215 (atomic_read(&fs_info->async_delalloc_pages) == 1216 0)); 1217 } 1218 1219 *nr_written += nr_pages; 1220 start = cur_end + 1; 1221 } 1222 *page_started = 1; 1223 return 0; 1224 } 1225 1226 static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info, 1227 u64 bytenr, u64 num_bytes) 1228 { 1229 int ret; 1230 struct btrfs_ordered_sum *sums; 1231 LIST_HEAD(list); 1232 1233 ret = btrfs_lookup_csums_range(fs_info->csum_root, bytenr, 1234 bytenr + num_bytes - 1, &list, 0); 1235 if (ret == 0 && list_empty(&list)) 1236 return 0; 1237 1238 while (!list_empty(&list)) { 1239 sums = list_entry(list.next, struct btrfs_ordered_sum, list); 1240 list_del(&sums->list); 1241 kfree(sums); 1242 } 1243 return 1; 1244 } 1245 1246 /* 1247 * when nowcow writeback call back. This checks for snapshots or COW copies 1248 * of the extents that exist in the file, and COWs the file as required. 1249 * 1250 * If no cow copies or snapshots exist, we write directly to the existing 1251 * blocks on disk 1252 */ 1253 static noinline int run_delalloc_nocow(struct inode *inode, 1254 struct page *locked_page, 1255 u64 start, u64 end, int *page_started, int force, 1256 unsigned long *nr_written) 1257 { 1258 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1259 struct btrfs_root *root = BTRFS_I(inode)->root; 1260 struct extent_buffer *leaf; 1261 struct btrfs_path *path; 1262 struct btrfs_file_extent_item *fi; 1263 struct btrfs_key found_key; 1264 struct extent_map *em; 1265 u64 cow_start; 1266 u64 cur_offset; 1267 u64 extent_end; 1268 u64 extent_offset; 1269 u64 disk_bytenr; 1270 u64 num_bytes; 1271 u64 disk_num_bytes; 1272 u64 ram_bytes; 1273 int extent_type; 1274 int ret, err; 1275 int type; 1276 int nocow; 1277 int check_prev = 1; 1278 bool nolock; 1279 u64 ino = btrfs_ino(BTRFS_I(inode)); 1280 1281 path = btrfs_alloc_path(); 1282 if (!path) { 1283 extent_clear_unlock_delalloc(inode, start, end, end, 1284 locked_page, 1285 EXTENT_LOCKED | EXTENT_DELALLOC | 1286 EXTENT_DO_ACCOUNTING | 1287 EXTENT_DEFRAG, PAGE_UNLOCK | 1288 PAGE_CLEAR_DIRTY | 1289 PAGE_SET_WRITEBACK | 1290 PAGE_END_WRITEBACK); 1291 return -ENOMEM; 1292 } 1293 1294 nolock = btrfs_is_free_space_inode(BTRFS_I(inode)); 1295 1296 cow_start = (u64)-1; 1297 cur_offset = start; 1298 while (1) { 1299 ret = btrfs_lookup_file_extent(NULL, root, path, ino, 1300 cur_offset, 0); 1301 if (ret < 0) 1302 goto error; 1303 if (ret > 0 && path->slots[0] > 0 && check_prev) { 1304 leaf = path->nodes[0]; 1305 btrfs_item_key_to_cpu(leaf, &found_key, 1306 path->slots[0] - 1); 1307 if (found_key.objectid == ino && 1308 found_key.type == BTRFS_EXTENT_DATA_KEY) 1309 path->slots[0]--; 1310 } 1311 check_prev = 0; 1312 next_slot: 1313 leaf = path->nodes[0]; 1314 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1315 ret = btrfs_next_leaf(root, path); 1316 if (ret < 0) 1317 goto error; 1318 if (ret > 0) 1319 break; 1320 leaf = path->nodes[0]; 1321 } 1322 1323 nocow = 0; 1324 disk_bytenr = 0; 1325 num_bytes = 0; 1326 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1327 1328 if (found_key.objectid > ino) 1329 break; 1330 if (WARN_ON_ONCE(found_key.objectid < ino) || 1331 found_key.type < BTRFS_EXTENT_DATA_KEY) { 1332 path->slots[0]++; 1333 goto next_slot; 1334 } 1335 if (found_key.type > BTRFS_EXTENT_DATA_KEY || 1336 found_key.offset > end) 1337 break; 1338 1339 if (found_key.offset > cur_offset) { 1340 extent_end = found_key.offset; 1341 extent_type = 0; 1342 goto out_check; 1343 } 1344 1345 fi = btrfs_item_ptr(leaf, path->slots[0], 1346 struct btrfs_file_extent_item); 1347 extent_type = btrfs_file_extent_type(leaf, fi); 1348 1349 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); 1350 if (extent_type == BTRFS_FILE_EXTENT_REG || 1351 extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1352 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 1353 extent_offset = btrfs_file_extent_offset(leaf, fi); 1354 extent_end = found_key.offset + 1355 btrfs_file_extent_num_bytes(leaf, fi); 1356 disk_num_bytes = 1357 btrfs_file_extent_disk_num_bytes(leaf, fi); 1358 if (extent_end <= start) { 1359 path->slots[0]++; 1360 goto next_slot; 1361 } 1362 if (disk_bytenr == 0) 1363 goto out_check; 1364 if (btrfs_file_extent_compression(leaf, fi) || 1365 btrfs_file_extent_encryption(leaf, fi) || 1366 btrfs_file_extent_other_encoding(leaf, fi)) 1367 goto out_check; 1368 if (extent_type == BTRFS_FILE_EXTENT_REG && !force) 1369 goto out_check; 1370 if (btrfs_extent_readonly(fs_info, disk_bytenr)) 1371 goto out_check; 1372 if (btrfs_cross_ref_exist(root, ino, 1373 found_key.offset - 1374 extent_offset, disk_bytenr)) 1375 goto out_check; 1376 disk_bytenr += extent_offset; 1377 disk_bytenr += cur_offset - found_key.offset; 1378 num_bytes = min(end + 1, extent_end) - cur_offset; 1379 /* 1380 * if there are pending snapshots for this root, 1381 * we fall into common COW way. 1382 */ 1383 if (!nolock) { 1384 err = btrfs_start_write_no_snapshoting(root); 1385 if (!err) 1386 goto out_check; 1387 } 1388 /* 1389 * force cow if csum exists in the range. 1390 * this ensure that csum for a given extent are 1391 * either valid or do not exist. 1392 */ 1393 if (csum_exist_in_range(fs_info, disk_bytenr, 1394 num_bytes)) { 1395 if (!nolock) 1396 btrfs_end_write_no_snapshoting(root); 1397 goto out_check; 1398 } 1399 if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr)) { 1400 if (!nolock) 1401 btrfs_end_write_no_snapshoting(root); 1402 goto out_check; 1403 } 1404 nocow = 1; 1405 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 1406 extent_end = found_key.offset + 1407 btrfs_file_extent_inline_len(leaf, 1408 path->slots[0], fi); 1409 extent_end = ALIGN(extent_end, 1410 fs_info->sectorsize); 1411 } else { 1412 BUG_ON(1); 1413 } 1414 out_check: 1415 if (extent_end <= start) { 1416 path->slots[0]++; 1417 if (!nolock && nocow) 1418 btrfs_end_write_no_snapshoting(root); 1419 if (nocow) 1420 btrfs_dec_nocow_writers(fs_info, disk_bytenr); 1421 goto next_slot; 1422 } 1423 if (!nocow) { 1424 if (cow_start == (u64)-1) 1425 cow_start = cur_offset; 1426 cur_offset = extent_end; 1427 if (cur_offset > end) 1428 break; 1429 path->slots[0]++; 1430 goto next_slot; 1431 } 1432 1433 btrfs_release_path(path); 1434 if (cow_start != (u64)-1) { 1435 ret = cow_file_range(inode, locked_page, 1436 cow_start, found_key.offset - 1, 1437 end, page_started, nr_written, 1, 1438 NULL); 1439 if (ret) { 1440 if (!nolock && nocow) 1441 btrfs_end_write_no_snapshoting(root); 1442 if (nocow) 1443 btrfs_dec_nocow_writers(fs_info, 1444 disk_bytenr); 1445 goto error; 1446 } 1447 cow_start = (u64)-1; 1448 } 1449 1450 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1451 u64 orig_start = found_key.offset - extent_offset; 1452 1453 em = create_io_em(inode, cur_offset, num_bytes, 1454 orig_start, 1455 disk_bytenr, /* block_start */ 1456 num_bytes, /* block_len */ 1457 disk_num_bytes, /* orig_block_len */ 1458 ram_bytes, BTRFS_COMPRESS_NONE, 1459 BTRFS_ORDERED_PREALLOC); 1460 if (IS_ERR(em)) { 1461 if (!nolock && nocow) 1462 btrfs_end_write_no_snapshoting(root); 1463 if (nocow) 1464 btrfs_dec_nocow_writers(fs_info, 1465 disk_bytenr); 1466 ret = PTR_ERR(em); 1467 goto error; 1468 } 1469 free_extent_map(em); 1470 } 1471 1472 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1473 type = BTRFS_ORDERED_PREALLOC; 1474 } else { 1475 type = BTRFS_ORDERED_NOCOW; 1476 } 1477 1478 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr, 1479 num_bytes, num_bytes, type); 1480 if (nocow) 1481 btrfs_dec_nocow_writers(fs_info, disk_bytenr); 1482 BUG_ON(ret); /* -ENOMEM */ 1483 1484 if (root->root_key.objectid == 1485 BTRFS_DATA_RELOC_TREE_OBJECTID) 1486 /* 1487 * Error handled later, as we must prevent 1488 * extent_clear_unlock_delalloc() in error handler 1489 * from freeing metadata of created ordered extent. 1490 */ 1491 ret = btrfs_reloc_clone_csums(inode, cur_offset, 1492 num_bytes); 1493 1494 extent_clear_unlock_delalloc(inode, cur_offset, 1495 cur_offset + num_bytes - 1, end, 1496 locked_page, EXTENT_LOCKED | 1497 EXTENT_DELALLOC | 1498 EXTENT_CLEAR_DATA_RESV, 1499 PAGE_UNLOCK | PAGE_SET_PRIVATE2); 1500 1501 if (!nolock && nocow) 1502 btrfs_end_write_no_snapshoting(root); 1503 cur_offset = extent_end; 1504 1505 /* 1506 * btrfs_reloc_clone_csums() error, now we're OK to call error 1507 * handler, as metadata for created ordered extent will only 1508 * be freed by btrfs_finish_ordered_io(). 1509 */ 1510 if (ret) 1511 goto error; 1512 if (cur_offset > end) 1513 break; 1514 } 1515 btrfs_release_path(path); 1516 1517 if (cur_offset <= end && cow_start == (u64)-1) { 1518 cow_start = cur_offset; 1519 cur_offset = end; 1520 } 1521 1522 if (cow_start != (u64)-1) { 1523 ret = cow_file_range(inode, locked_page, cow_start, end, end, 1524 page_started, nr_written, 1, NULL); 1525 if (ret) 1526 goto error; 1527 } 1528 1529 error: 1530 if (ret && cur_offset < end) 1531 extent_clear_unlock_delalloc(inode, cur_offset, end, end, 1532 locked_page, EXTENT_LOCKED | 1533 EXTENT_DELALLOC | EXTENT_DEFRAG | 1534 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | 1535 PAGE_CLEAR_DIRTY | 1536 PAGE_SET_WRITEBACK | 1537 PAGE_END_WRITEBACK); 1538 btrfs_free_path(path); 1539 return ret; 1540 } 1541 1542 static inline int need_force_cow(struct inode *inode, u64 start, u64 end) 1543 { 1544 1545 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && 1546 !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)) 1547 return 0; 1548 1549 /* 1550 * @defrag_bytes is a hint value, no spinlock held here, 1551 * if is not zero, it means the file is defragging. 1552 * Force cow if given extent needs to be defragged. 1553 */ 1554 if (BTRFS_I(inode)->defrag_bytes && 1555 test_range_bit(&BTRFS_I(inode)->io_tree, start, end, 1556 EXTENT_DEFRAG, 0, NULL)) 1557 return 1; 1558 1559 return 0; 1560 } 1561 1562 /* 1563 * extent_io.c call back to do delayed allocation processing 1564 */ 1565 static int run_delalloc_range(void *private_data, struct page *locked_page, 1566 u64 start, u64 end, int *page_started, 1567 unsigned long *nr_written) 1568 { 1569 struct inode *inode = private_data; 1570 int ret; 1571 int force_cow = need_force_cow(inode, start, end); 1572 1573 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW && !force_cow) { 1574 ret = run_delalloc_nocow(inode, locked_page, start, end, 1575 page_started, 1, nr_written); 1576 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC && !force_cow) { 1577 ret = run_delalloc_nocow(inode, locked_page, start, end, 1578 page_started, 0, nr_written); 1579 } else if (!inode_need_compress(inode)) { 1580 ret = cow_file_range(inode, locked_page, start, end, end, 1581 page_started, nr_written, 1, NULL); 1582 } else { 1583 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 1584 &BTRFS_I(inode)->runtime_flags); 1585 ret = cow_file_range_async(inode, locked_page, start, end, 1586 page_started, nr_written); 1587 } 1588 if (ret) 1589 btrfs_cleanup_ordered_extents(inode, start, end - start + 1); 1590 return ret; 1591 } 1592 1593 static void btrfs_split_extent_hook(void *private_data, 1594 struct extent_state *orig, u64 split) 1595 { 1596 struct inode *inode = private_data; 1597 u64 size; 1598 1599 /* not delalloc, ignore it */ 1600 if (!(orig->state & EXTENT_DELALLOC)) 1601 return; 1602 1603 size = orig->end - orig->start + 1; 1604 if (size > BTRFS_MAX_EXTENT_SIZE) { 1605 u32 num_extents; 1606 u64 new_size; 1607 1608 /* 1609 * See the explanation in btrfs_merge_extent_hook, the same 1610 * applies here, just in reverse. 1611 */ 1612 new_size = orig->end - split + 1; 1613 num_extents = count_max_extents(new_size); 1614 new_size = split - orig->start; 1615 num_extents += count_max_extents(new_size); 1616 if (count_max_extents(size) >= num_extents) 1617 return; 1618 } 1619 1620 spin_lock(&BTRFS_I(inode)->lock); 1621 BTRFS_I(inode)->outstanding_extents++; 1622 spin_unlock(&BTRFS_I(inode)->lock); 1623 } 1624 1625 /* 1626 * extent_io.c merge_extent_hook, used to track merged delayed allocation 1627 * extents so we can keep track of new extents that are just merged onto old 1628 * extents, such as when we are doing sequential writes, so we can properly 1629 * account for the metadata space we'll need. 1630 */ 1631 static void btrfs_merge_extent_hook(void *private_data, 1632 struct extent_state *new, 1633 struct extent_state *other) 1634 { 1635 struct inode *inode = private_data; 1636 u64 new_size, old_size; 1637 u32 num_extents; 1638 1639 /* not delalloc, ignore it */ 1640 if (!(other->state & EXTENT_DELALLOC)) 1641 return; 1642 1643 if (new->start > other->start) 1644 new_size = new->end - other->start + 1; 1645 else 1646 new_size = other->end - new->start + 1; 1647 1648 /* we're not bigger than the max, unreserve the space and go */ 1649 if (new_size <= BTRFS_MAX_EXTENT_SIZE) { 1650 spin_lock(&BTRFS_I(inode)->lock); 1651 BTRFS_I(inode)->outstanding_extents--; 1652 spin_unlock(&BTRFS_I(inode)->lock); 1653 return; 1654 } 1655 1656 /* 1657 * We have to add up either side to figure out how many extents were 1658 * accounted for before we merged into one big extent. If the number of 1659 * extents we accounted for is <= the amount we need for the new range 1660 * then we can return, otherwise drop. Think of it like this 1661 * 1662 * [ 4k][MAX_SIZE] 1663 * 1664 * So we've grown the extent by a MAX_SIZE extent, this would mean we 1665 * need 2 outstanding extents, on one side we have 1 and the other side 1666 * we have 1 so they are == and we can return. But in this case 1667 * 1668 * [MAX_SIZE+4k][MAX_SIZE+4k] 1669 * 1670 * Each range on their own accounts for 2 extents, but merged together 1671 * they are only 3 extents worth of accounting, so we need to drop in 1672 * this case. 1673 */ 1674 old_size = other->end - other->start + 1; 1675 num_extents = count_max_extents(old_size); 1676 old_size = new->end - new->start + 1; 1677 num_extents += count_max_extents(old_size); 1678 if (count_max_extents(new_size) >= num_extents) 1679 return; 1680 1681 spin_lock(&BTRFS_I(inode)->lock); 1682 BTRFS_I(inode)->outstanding_extents--; 1683 spin_unlock(&BTRFS_I(inode)->lock); 1684 } 1685 1686 static void btrfs_add_delalloc_inodes(struct btrfs_root *root, 1687 struct inode *inode) 1688 { 1689 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1690 1691 spin_lock(&root->delalloc_lock); 1692 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) { 1693 list_add_tail(&BTRFS_I(inode)->delalloc_inodes, 1694 &root->delalloc_inodes); 1695 set_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1696 &BTRFS_I(inode)->runtime_flags); 1697 root->nr_delalloc_inodes++; 1698 if (root->nr_delalloc_inodes == 1) { 1699 spin_lock(&fs_info->delalloc_root_lock); 1700 BUG_ON(!list_empty(&root->delalloc_root)); 1701 list_add_tail(&root->delalloc_root, 1702 &fs_info->delalloc_roots); 1703 spin_unlock(&fs_info->delalloc_root_lock); 1704 } 1705 } 1706 spin_unlock(&root->delalloc_lock); 1707 } 1708 1709 static void btrfs_del_delalloc_inode(struct btrfs_root *root, 1710 struct btrfs_inode *inode) 1711 { 1712 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb); 1713 1714 spin_lock(&root->delalloc_lock); 1715 if (!list_empty(&inode->delalloc_inodes)) { 1716 list_del_init(&inode->delalloc_inodes); 1717 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1718 &inode->runtime_flags); 1719 root->nr_delalloc_inodes--; 1720 if (!root->nr_delalloc_inodes) { 1721 spin_lock(&fs_info->delalloc_root_lock); 1722 BUG_ON(list_empty(&root->delalloc_root)); 1723 list_del_init(&root->delalloc_root); 1724 spin_unlock(&fs_info->delalloc_root_lock); 1725 } 1726 } 1727 spin_unlock(&root->delalloc_lock); 1728 } 1729 1730 /* 1731 * extent_io.c set_bit_hook, used to track delayed allocation 1732 * bytes in this file, and to maintain the list of inodes that 1733 * have pending delalloc work to be done. 1734 */ 1735 static void btrfs_set_bit_hook(void *private_data, 1736 struct extent_state *state, unsigned *bits) 1737 { 1738 struct inode *inode = private_data; 1739 1740 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1741 1742 if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC)) 1743 WARN_ON(1); 1744 /* 1745 * set_bit and clear bit hooks normally require _irqsave/restore 1746 * but in this case, we are only testing for the DELALLOC 1747 * bit, which is only set or cleared with irqs on 1748 */ 1749 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { 1750 struct btrfs_root *root = BTRFS_I(inode)->root; 1751 u64 len = state->end + 1 - state->start; 1752 bool do_list = !btrfs_is_free_space_inode(BTRFS_I(inode)); 1753 1754 if (*bits & EXTENT_FIRST_DELALLOC) { 1755 *bits &= ~EXTENT_FIRST_DELALLOC; 1756 } else { 1757 spin_lock(&BTRFS_I(inode)->lock); 1758 BTRFS_I(inode)->outstanding_extents++; 1759 spin_unlock(&BTRFS_I(inode)->lock); 1760 } 1761 1762 /* For sanity tests */ 1763 if (btrfs_is_testing(fs_info)) 1764 return; 1765 1766 percpu_counter_add_batch(&fs_info->delalloc_bytes, len, 1767 fs_info->delalloc_batch); 1768 spin_lock(&BTRFS_I(inode)->lock); 1769 BTRFS_I(inode)->delalloc_bytes += len; 1770 if (*bits & EXTENT_DEFRAG) 1771 BTRFS_I(inode)->defrag_bytes += len; 1772 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1773 &BTRFS_I(inode)->runtime_flags)) 1774 btrfs_add_delalloc_inodes(root, inode); 1775 spin_unlock(&BTRFS_I(inode)->lock); 1776 } 1777 1778 if (!(state->state & EXTENT_DELALLOC_NEW) && 1779 (*bits & EXTENT_DELALLOC_NEW)) { 1780 spin_lock(&BTRFS_I(inode)->lock); 1781 BTRFS_I(inode)->new_delalloc_bytes += state->end + 1 - 1782 state->start; 1783 spin_unlock(&BTRFS_I(inode)->lock); 1784 } 1785 } 1786 1787 /* 1788 * extent_io.c clear_bit_hook, see set_bit_hook for why 1789 */ 1790 static void btrfs_clear_bit_hook(void *private_data, 1791 struct extent_state *state, 1792 unsigned *bits) 1793 { 1794 struct btrfs_inode *inode = BTRFS_I((struct inode *)private_data); 1795 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb); 1796 u64 len = state->end + 1 - state->start; 1797 u32 num_extents = count_max_extents(len); 1798 1799 spin_lock(&inode->lock); 1800 if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) 1801 inode->defrag_bytes -= len; 1802 spin_unlock(&inode->lock); 1803 1804 /* 1805 * set_bit and clear bit hooks normally require _irqsave/restore 1806 * but in this case, we are only testing for the DELALLOC 1807 * bit, which is only set or cleared with irqs on 1808 */ 1809 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { 1810 struct btrfs_root *root = inode->root; 1811 bool do_list = !btrfs_is_free_space_inode(inode); 1812 1813 if (*bits & EXTENT_FIRST_DELALLOC) { 1814 *bits &= ~EXTENT_FIRST_DELALLOC; 1815 } else if (!(*bits & EXTENT_CLEAR_META_RESV)) { 1816 spin_lock(&inode->lock); 1817 inode->outstanding_extents -= num_extents; 1818 spin_unlock(&inode->lock); 1819 } 1820 1821 /* 1822 * We don't reserve metadata space for space cache inodes so we 1823 * don't need to call dellalloc_release_metadata if there is an 1824 * error. 1825 */ 1826 if (*bits & EXTENT_CLEAR_META_RESV && 1827 root != fs_info->tree_root) 1828 btrfs_delalloc_release_metadata(inode, len); 1829 1830 /* For sanity tests. */ 1831 if (btrfs_is_testing(fs_info)) 1832 return; 1833 1834 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID && 1835 do_list && !(state->state & EXTENT_NORESERVE) && 1836 (*bits & EXTENT_CLEAR_DATA_RESV)) 1837 btrfs_free_reserved_data_space_noquota( 1838 &inode->vfs_inode, 1839 state->start, len); 1840 1841 percpu_counter_add_batch(&fs_info->delalloc_bytes, -len, 1842 fs_info->delalloc_batch); 1843 spin_lock(&inode->lock); 1844 inode->delalloc_bytes -= len; 1845 if (do_list && inode->delalloc_bytes == 0 && 1846 test_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1847 &inode->runtime_flags)) 1848 btrfs_del_delalloc_inode(root, inode); 1849 spin_unlock(&inode->lock); 1850 } 1851 1852 if ((state->state & EXTENT_DELALLOC_NEW) && 1853 (*bits & EXTENT_DELALLOC_NEW)) { 1854 spin_lock(&inode->lock); 1855 ASSERT(inode->new_delalloc_bytes >= len); 1856 inode->new_delalloc_bytes -= len; 1857 spin_unlock(&inode->lock); 1858 } 1859 } 1860 1861 /* 1862 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure 1863 * we don't create bios that span stripes or chunks 1864 * 1865 * return 1 if page cannot be merged to bio 1866 * return 0 if page can be merged to bio 1867 * return error otherwise 1868 */ 1869 int btrfs_merge_bio_hook(struct page *page, unsigned long offset, 1870 size_t size, struct bio *bio, 1871 unsigned long bio_flags) 1872 { 1873 struct inode *inode = page->mapping->host; 1874 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1875 u64 logical = (u64)bio->bi_iter.bi_sector << 9; 1876 u64 length = 0; 1877 u64 map_length; 1878 int ret; 1879 1880 if (bio_flags & EXTENT_BIO_COMPRESSED) 1881 return 0; 1882 1883 length = bio->bi_iter.bi_size; 1884 map_length = length; 1885 ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length, 1886 NULL, 0); 1887 if (ret < 0) 1888 return ret; 1889 if (map_length < length + size) 1890 return 1; 1891 return 0; 1892 } 1893 1894 /* 1895 * in order to insert checksums into the metadata in large chunks, 1896 * we wait until bio submission time. All the pages in the bio are 1897 * checksummed and sums are attached onto the ordered extent record. 1898 * 1899 * At IO completion time the cums attached on the ordered extent record 1900 * are inserted into the btree 1901 */ 1902 static blk_status_t __btrfs_submit_bio_start(void *private_data, struct bio *bio, 1903 int mirror_num, unsigned long bio_flags, 1904 u64 bio_offset) 1905 { 1906 struct inode *inode = private_data; 1907 blk_status_t ret = 0; 1908 1909 ret = btrfs_csum_one_bio(inode, bio, 0, 0); 1910 BUG_ON(ret); /* -ENOMEM */ 1911 return 0; 1912 } 1913 1914 /* 1915 * in order to insert checksums into the metadata in large chunks, 1916 * we wait until bio submission time. All the pages in the bio are 1917 * checksummed and sums are attached onto the ordered extent record. 1918 * 1919 * At IO completion time the cums attached on the ordered extent record 1920 * are inserted into the btree 1921 */ 1922 static blk_status_t __btrfs_submit_bio_done(void *private_data, struct bio *bio, 1923 int mirror_num, unsigned long bio_flags, 1924 u64 bio_offset) 1925 { 1926 struct inode *inode = private_data; 1927 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1928 blk_status_t ret; 1929 1930 ret = btrfs_map_bio(fs_info, bio, mirror_num, 1); 1931 if (ret) { 1932 bio->bi_status = ret; 1933 bio_endio(bio); 1934 } 1935 return ret; 1936 } 1937 1938 /* 1939 * extent_io.c submission hook. This does the right thing for csum calculation 1940 * on write, or reading the csums from the tree before a read 1941 */ 1942 static blk_status_t btrfs_submit_bio_hook(void *private_data, struct bio *bio, 1943 int mirror_num, unsigned long bio_flags, 1944 u64 bio_offset) 1945 { 1946 struct inode *inode = private_data; 1947 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1948 struct btrfs_root *root = BTRFS_I(inode)->root; 1949 enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA; 1950 blk_status_t ret = 0; 1951 int skip_sum; 1952 int async = !atomic_read(&BTRFS_I(inode)->sync_writers); 1953 1954 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 1955 1956 if (btrfs_is_free_space_inode(BTRFS_I(inode))) 1957 metadata = BTRFS_WQ_ENDIO_FREE_SPACE; 1958 1959 if (bio_op(bio) != REQ_OP_WRITE) { 1960 ret = btrfs_bio_wq_end_io(fs_info, bio, metadata); 1961 if (ret) 1962 goto out; 1963 1964 if (bio_flags & EXTENT_BIO_COMPRESSED) { 1965 ret = btrfs_submit_compressed_read(inode, bio, 1966 mirror_num, 1967 bio_flags); 1968 goto out; 1969 } else if (!skip_sum) { 1970 ret = btrfs_lookup_bio_sums(inode, bio, NULL); 1971 if (ret) 1972 goto out; 1973 } 1974 goto mapit; 1975 } else if (async && !skip_sum) { 1976 /* csum items have already been cloned */ 1977 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) 1978 goto mapit; 1979 /* we're doing a write, do the async checksumming */ 1980 ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, bio_flags, 1981 bio_offset, inode, 1982 __btrfs_submit_bio_start, 1983 __btrfs_submit_bio_done); 1984 goto out; 1985 } else if (!skip_sum) { 1986 ret = btrfs_csum_one_bio(inode, bio, 0, 0); 1987 if (ret) 1988 goto out; 1989 } 1990 1991 mapit: 1992 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0); 1993 1994 out: 1995 if (ret) { 1996 bio->bi_status = ret; 1997 bio_endio(bio); 1998 } 1999 return ret; 2000 } 2001 2002 /* 2003 * given a list of ordered sums record them in the inode. This happens 2004 * at IO completion time based on sums calculated at bio submission time. 2005 */ 2006 static noinline int add_pending_csums(struct btrfs_trans_handle *trans, 2007 struct inode *inode, struct list_head *list) 2008 { 2009 struct btrfs_ordered_sum *sum; 2010 2011 list_for_each_entry(sum, list, list) { 2012 trans->adding_csums = 1; 2013 btrfs_csum_file_blocks(trans, 2014 BTRFS_I(inode)->root->fs_info->csum_root, sum); 2015 trans->adding_csums = 0; 2016 } 2017 return 0; 2018 } 2019 2020 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, 2021 struct extent_state **cached_state, int dedupe) 2022 { 2023 WARN_ON((end & (PAGE_SIZE - 1)) == 0); 2024 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end, 2025 cached_state); 2026 } 2027 2028 /* see btrfs_writepage_start_hook for details on why this is required */ 2029 struct btrfs_writepage_fixup { 2030 struct page *page; 2031 struct btrfs_work work; 2032 }; 2033 2034 static void btrfs_writepage_fixup_worker(struct btrfs_work *work) 2035 { 2036 struct btrfs_writepage_fixup *fixup; 2037 struct btrfs_ordered_extent *ordered; 2038 struct extent_state *cached_state = NULL; 2039 struct extent_changeset *data_reserved = NULL; 2040 struct page *page; 2041 struct inode *inode; 2042 u64 page_start; 2043 u64 page_end; 2044 int ret; 2045 2046 fixup = container_of(work, struct btrfs_writepage_fixup, work); 2047 page = fixup->page; 2048 again: 2049 lock_page(page); 2050 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { 2051 ClearPageChecked(page); 2052 goto out_page; 2053 } 2054 2055 inode = page->mapping->host; 2056 page_start = page_offset(page); 2057 page_end = page_offset(page) + PAGE_SIZE - 1; 2058 2059 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 2060 &cached_state); 2061 2062 /* already ordered? We're done */ 2063 if (PagePrivate2(page)) 2064 goto out; 2065 2066 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start, 2067 PAGE_SIZE); 2068 if (ordered) { 2069 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, 2070 page_end, &cached_state, GFP_NOFS); 2071 unlock_page(page); 2072 btrfs_start_ordered_extent(inode, ordered, 1); 2073 btrfs_put_ordered_extent(ordered); 2074 goto again; 2075 } 2076 2077 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, 2078 PAGE_SIZE); 2079 if (ret) { 2080 mapping_set_error(page->mapping, ret); 2081 end_extent_writepage(page, ret, page_start, page_end); 2082 ClearPageChecked(page); 2083 goto out; 2084 } 2085 2086 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state, 2087 0); 2088 ClearPageChecked(page); 2089 set_page_dirty(page); 2090 out: 2091 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, 2092 &cached_state, GFP_NOFS); 2093 out_page: 2094 unlock_page(page); 2095 put_page(page); 2096 kfree(fixup); 2097 extent_changeset_free(data_reserved); 2098 } 2099 2100 /* 2101 * There are a few paths in the higher layers of the kernel that directly 2102 * set the page dirty bit without asking the filesystem if it is a 2103 * good idea. This causes problems because we want to make sure COW 2104 * properly happens and the data=ordered rules are followed. 2105 * 2106 * In our case any range that doesn't have the ORDERED bit set 2107 * hasn't been properly setup for IO. We kick off an async process 2108 * to fix it up. The async helper will wait for ordered extents, set 2109 * the delalloc bit and make it safe to write the page. 2110 */ 2111 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) 2112 { 2113 struct inode *inode = page->mapping->host; 2114 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2115 struct btrfs_writepage_fixup *fixup; 2116 2117 /* this page is properly in the ordered list */ 2118 if (TestClearPagePrivate2(page)) 2119 return 0; 2120 2121 if (PageChecked(page)) 2122 return -EAGAIN; 2123 2124 fixup = kzalloc(sizeof(*fixup), GFP_NOFS); 2125 if (!fixup) 2126 return -EAGAIN; 2127 2128 SetPageChecked(page); 2129 get_page(page); 2130 btrfs_init_work(&fixup->work, btrfs_fixup_helper, 2131 btrfs_writepage_fixup_worker, NULL, NULL); 2132 fixup->page = page; 2133 btrfs_queue_work(fs_info->fixup_workers, &fixup->work); 2134 return -EBUSY; 2135 } 2136 2137 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, 2138 struct inode *inode, u64 file_pos, 2139 u64 disk_bytenr, u64 disk_num_bytes, 2140 u64 num_bytes, u64 ram_bytes, 2141 u8 compression, u8 encryption, 2142 u16 other_encoding, int extent_type) 2143 { 2144 struct btrfs_root *root = BTRFS_I(inode)->root; 2145 struct btrfs_file_extent_item *fi; 2146 struct btrfs_path *path; 2147 struct extent_buffer *leaf; 2148 struct btrfs_key ins; 2149 u64 qg_released; 2150 int extent_inserted = 0; 2151 int ret; 2152 2153 path = btrfs_alloc_path(); 2154 if (!path) 2155 return -ENOMEM; 2156 2157 /* 2158 * we may be replacing one extent in the tree with another. 2159 * The new extent is pinned in the extent map, and we don't want 2160 * to drop it from the cache until it is completely in the btree. 2161 * 2162 * So, tell btrfs_drop_extents to leave this extent in the cache. 2163 * the caller is expected to unpin it and allow it to be merged 2164 * with the others. 2165 */ 2166 ret = __btrfs_drop_extents(trans, root, inode, path, file_pos, 2167 file_pos + num_bytes, NULL, 0, 2168 1, sizeof(*fi), &extent_inserted); 2169 if (ret) 2170 goto out; 2171 2172 if (!extent_inserted) { 2173 ins.objectid = btrfs_ino(BTRFS_I(inode)); 2174 ins.offset = file_pos; 2175 ins.type = BTRFS_EXTENT_DATA_KEY; 2176 2177 path->leave_spinning = 1; 2178 ret = btrfs_insert_empty_item(trans, root, path, &ins, 2179 sizeof(*fi)); 2180 if (ret) 2181 goto out; 2182 } 2183 leaf = path->nodes[0]; 2184 fi = btrfs_item_ptr(leaf, path->slots[0], 2185 struct btrfs_file_extent_item); 2186 btrfs_set_file_extent_generation(leaf, fi, trans->transid); 2187 btrfs_set_file_extent_type(leaf, fi, extent_type); 2188 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); 2189 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes); 2190 btrfs_set_file_extent_offset(leaf, fi, 0); 2191 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); 2192 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes); 2193 btrfs_set_file_extent_compression(leaf, fi, compression); 2194 btrfs_set_file_extent_encryption(leaf, fi, encryption); 2195 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding); 2196 2197 btrfs_mark_buffer_dirty(leaf); 2198 btrfs_release_path(path); 2199 2200 inode_add_bytes(inode, num_bytes); 2201 2202 ins.objectid = disk_bytenr; 2203 ins.offset = disk_num_bytes; 2204 ins.type = BTRFS_EXTENT_ITEM_KEY; 2205 2206 /* 2207 * Release the reserved range from inode dirty range map, as it is 2208 * already moved into delayed_ref_head 2209 */ 2210 ret = btrfs_qgroup_release_data(inode, file_pos, ram_bytes); 2211 if (ret < 0) 2212 goto out; 2213 qg_released = ret; 2214 ret = btrfs_alloc_reserved_file_extent(trans, root->root_key.objectid, 2215 btrfs_ino(BTRFS_I(inode)), file_pos, qg_released, &ins); 2216 out: 2217 btrfs_free_path(path); 2218 2219 return ret; 2220 } 2221 2222 /* snapshot-aware defrag */ 2223 struct sa_defrag_extent_backref { 2224 struct rb_node node; 2225 struct old_sa_defrag_extent *old; 2226 u64 root_id; 2227 u64 inum; 2228 u64 file_pos; 2229 u64 extent_offset; 2230 u64 num_bytes; 2231 u64 generation; 2232 }; 2233 2234 struct old_sa_defrag_extent { 2235 struct list_head list; 2236 struct new_sa_defrag_extent *new; 2237 2238 u64 extent_offset; 2239 u64 bytenr; 2240 u64 offset; 2241 u64 len; 2242 int count; 2243 }; 2244 2245 struct new_sa_defrag_extent { 2246 struct rb_root root; 2247 struct list_head head; 2248 struct btrfs_path *path; 2249 struct inode *inode; 2250 u64 file_pos; 2251 u64 len; 2252 u64 bytenr; 2253 u64 disk_len; 2254 u8 compress_type; 2255 }; 2256 2257 static int backref_comp(struct sa_defrag_extent_backref *b1, 2258 struct sa_defrag_extent_backref *b2) 2259 { 2260 if (b1->root_id < b2->root_id) 2261 return -1; 2262 else if (b1->root_id > b2->root_id) 2263 return 1; 2264 2265 if (b1->inum < b2->inum) 2266 return -1; 2267 else if (b1->inum > b2->inum) 2268 return 1; 2269 2270 if (b1->file_pos < b2->file_pos) 2271 return -1; 2272 else if (b1->file_pos > b2->file_pos) 2273 return 1; 2274 2275 /* 2276 * [------------------------------] ===> (a range of space) 2277 * |<--->| |<---->| =============> (fs/file tree A) 2278 * |<---------------------------->| ===> (fs/file tree B) 2279 * 2280 * A range of space can refer to two file extents in one tree while 2281 * refer to only one file extent in another tree. 2282 * 2283 * So we may process a disk offset more than one time(two extents in A) 2284 * and locate at the same extent(one extent in B), then insert two same 2285 * backrefs(both refer to the extent in B). 2286 */ 2287 return 0; 2288 } 2289 2290 static void backref_insert(struct rb_root *root, 2291 struct sa_defrag_extent_backref *backref) 2292 { 2293 struct rb_node **p = &root->rb_node; 2294 struct rb_node *parent = NULL; 2295 struct sa_defrag_extent_backref *entry; 2296 int ret; 2297 2298 while (*p) { 2299 parent = *p; 2300 entry = rb_entry(parent, struct sa_defrag_extent_backref, node); 2301 2302 ret = backref_comp(backref, entry); 2303 if (ret < 0) 2304 p = &(*p)->rb_left; 2305 else 2306 p = &(*p)->rb_right; 2307 } 2308 2309 rb_link_node(&backref->node, parent, p); 2310 rb_insert_color(&backref->node, root); 2311 } 2312 2313 /* 2314 * Note the backref might has changed, and in this case we just return 0. 2315 */ 2316 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id, 2317 void *ctx) 2318 { 2319 struct btrfs_file_extent_item *extent; 2320 struct old_sa_defrag_extent *old = ctx; 2321 struct new_sa_defrag_extent *new = old->new; 2322 struct btrfs_path *path = new->path; 2323 struct btrfs_key key; 2324 struct btrfs_root *root; 2325 struct sa_defrag_extent_backref *backref; 2326 struct extent_buffer *leaf; 2327 struct inode *inode = new->inode; 2328 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2329 int slot; 2330 int ret; 2331 u64 extent_offset; 2332 u64 num_bytes; 2333 2334 if (BTRFS_I(inode)->root->root_key.objectid == root_id && 2335 inum == btrfs_ino(BTRFS_I(inode))) 2336 return 0; 2337 2338 key.objectid = root_id; 2339 key.type = BTRFS_ROOT_ITEM_KEY; 2340 key.offset = (u64)-1; 2341 2342 root = btrfs_read_fs_root_no_name(fs_info, &key); 2343 if (IS_ERR(root)) { 2344 if (PTR_ERR(root) == -ENOENT) 2345 return 0; 2346 WARN_ON(1); 2347 btrfs_debug(fs_info, "inum=%llu, offset=%llu, root_id=%llu", 2348 inum, offset, root_id); 2349 return PTR_ERR(root); 2350 } 2351 2352 key.objectid = inum; 2353 key.type = BTRFS_EXTENT_DATA_KEY; 2354 if (offset > (u64)-1 << 32) 2355 key.offset = 0; 2356 else 2357 key.offset = offset; 2358 2359 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2360 if (WARN_ON(ret < 0)) 2361 return ret; 2362 ret = 0; 2363 2364 while (1) { 2365 cond_resched(); 2366 2367 leaf = path->nodes[0]; 2368 slot = path->slots[0]; 2369 2370 if (slot >= btrfs_header_nritems(leaf)) { 2371 ret = btrfs_next_leaf(root, path); 2372 if (ret < 0) { 2373 goto out; 2374 } else if (ret > 0) { 2375 ret = 0; 2376 goto out; 2377 } 2378 continue; 2379 } 2380 2381 path->slots[0]++; 2382 2383 btrfs_item_key_to_cpu(leaf, &key, slot); 2384 2385 if (key.objectid > inum) 2386 goto out; 2387 2388 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY) 2389 continue; 2390 2391 extent = btrfs_item_ptr(leaf, slot, 2392 struct btrfs_file_extent_item); 2393 2394 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr) 2395 continue; 2396 2397 /* 2398 * 'offset' refers to the exact key.offset, 2399 * NOT the 'offset' field in btrfs_extent_data_ref, ie. 2400 * (key.offset - extent_offset). 2401 */ 2402 if (key.offset != offset) 2403 continue; 2404 2405 extent_offset = btrfs_file_extent_offset(leaf, extent); 2406 num_bytes = btrfs_file_extent_num_bytes(leaf, extent); 2407 2408 if (extent_offset >= old->extent_offset + old->offset + 2409 old->len || extent_offset + num_bytes <= 2410 old->extent_offset + old->offset) 2411 continue; 2412 break; 2413 } 2414 2415 backref = kmalloc(sizeof(*backref), GFP_NOFS); 2416 if (!backref) { 2417 ret = -ENOENT; 2418 goto out; 2419 } 2420 2421 backref->root_id = root_id; 2422 backref->inum = inum; 2423 backref->file_pos = offset; 2424 backref->num_bytes = num_bytes; 2425 backref->extent_offset = extent_offset; 2426 backref->generation = btrfs_file_extent_generation(leaf, extent); 2427 backref->old = old; 2428 backref_insert(&new->root, backref); 2429 old->count++; 2430 out: 2431 btrfs_release_path(path); 2432 WARN_ON(ret); 2433 return ret; 2434 } 2435 2436 static noinline bool record_extent_backrefs(struct btrfs_path *path, 2437 struct new_sa_defrag_extent *new) 2438 { 2439 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); 2440 struct old_sa_defrag_extent *old, *tmp; 2441 int ret; 2442 2443 new->path = path; 2444 2445 list_for_each_entry_safe(old, tmp, &new->head, list) { 2446 ret = iterate_inodes_from_logical(old->bytenr + 2447 old->extent_offset, fs_info, 2448 path, record_one_backref, 2449 old); 2450 if (ret < 0 && ret != -ENOENT) 2451 return false; 2452 2453 /* no backref to be processed for this extent */ 2454 if (!old->count) { 2455 list_del(&old->list); 2456 kfree(old); 2457 } 2458 } 2459 2460 if (list_empty(&new->head)) 2461 return false; 2462 2463 return true; 2464 } 2465 2466 static int relink_is_mergable(struct extent_buffer *leaf, 2467 struct btrfs_file_extent_item *fi, 2468 struct new_sa_defrag_extent *new) 2469 { 2470 if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr) 2471 return 0; 2472 2473 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) 2474 return 0; 2475 2476 if (btrfs_file_extent_compression(leaf, fi) != new->compress_type) 2477 return 0; 2478 2479 if (btrfs_file_extent_encryption(leaf, fi) || 2480 btrfs_file_extent_other_encoding(leaf, fi)) 2481 return 0; 2482 2483 return 1; 2484 } 2485 2486 /* 2487 * Note the backref might has changed, and in this case we just return 0. 2488 */ 2489 static noinline int relink_extent_backref(struct btrfs_path *path, 2490 struct sa_defrag_extent_backref *prev, 2491 struct sa_defrag_extent_backref *backref) 2492 { 2493 struct btrfs_file_extent_item *extent; 2494 struct btrfs_file_extent_item *item; 2495 struct btrfs_ordered_extent *ordered; 2496 struct btrfs_trans_handle *trans; 2497 struct btrfs_root *root; 2498 struct btrfs_key key; 2499 struct extent_buffer *leaf; 2500 struct old_sa_defrag_extent *old = backref->old; 2501 struct new_sa_defrag_extent *new = old->new; 2502 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); 2503 struct inode *inode; 2504 struct extent_state *cached = NULL; 2505 int ret = 0; 2506 u64 start; 2507 u64 len; 2508 u64 lock_start; 2509 u64 lock_end; 2510 bool merge = false; 2511 int index; 2512 2513 if (prev && prev->root_id == backref->root_id && 2514 prev->inum == backref->inum && 2515 prev->file_pos + prev->num_bytes == backref->file_pos) 2516 merge = true; 2517 2518 /* step 1: get root */ 2519 key.objectid = backref->root_id; 2520 key.type = BTRFS_ROOT_ITEM_KEY; 2521 key.offset = (u64)-1; 2522 2523 index = srcu_read_lock(&fs_info->subvol_srcu); 2524 2525 root = btrfs_read_fs_root_no_name(fs_info, &key); 2526 if (IS_ERR(root)) { 2527 srcu_read_unlock(&fs_info->subvol_srcu, index); 2528 if (PTR_ERR(root) == -ENOENT) 2529 return 0; 2530 return PTR_ERR(root); 2531 } 2532 2533 if (btrfs_root_readonly(root)) { 2534 srcu_read_unlock(&fs_info->subvol_srcu, index); 2535 return 0; 2536 } 2537 2538 /* step 2: get inode */ 2539 key.objectid = backref->inum; 2540 key.type = BTRFS_INODE_ITEM_KEY; 2541 key.offset = 0; 2542 2543 inode = btrfs_iget(fs_info->sb, &key, root, NULL); 2544 if (IS_ERR(inode)) { 2545 srcu_read_unlock(&fs_info->subvol_srcu, index); 2546 return 0; 2547 } 2548 2549 srcu_read_unlock(&fs_info->subvol_srcu, index); 2550 2551 /* step 3: relink backref */ 2552 lock_start = backref->file_pos; 2553 lock_end = backref->file_pos + backref->num_bytes - 1; 2554 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end, 2555 &cached); 2556 2557 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end); 2558 if (ordered) { 2559 btrfs_put_ordered_extent(ordered); 2560 goto out_unlock; 2561 } 2562 2563 trans = btrfs_join_transaction(root); 2564 if (IS_ERR(trans)) { 2565 ret = PTR_ERR(trans); 2566 goto out_unlock; 2567 } 2568 2569 key.objectid = backref->inum; 2570 key.type = BTRFS_EXTENT_DATA_KEY; 2571 key.offset = backref->file_pos; 2572 2573 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2574 if (ret < 0) { 2575 goto out_free_path; 2576 } else if (ret > 0) { 2577 ret = 0; 2578 goto out_free_path; 2579 } 2580 2581 extent = btrfs_item_ptr(path->nodes[0], path->slots[0], 2582 struct btrfs_file_extent_item); 2583 2584 if (btrfs_file_extent_generation(path->nodes[0], extent) != 2585 backref->generation) 2586 goto out_free_path; 2587 2588 btrfs_release_path(path); 2589 2590 start = backref->file_pos; 2591 if (backref->extent_offset < old->extent_offset + old->offset) 2592 start += old->extent_offset + old->offset - 2593 backref->extent_offset; 2594 2595 len = min(backref->extent_offset + backref->num_bytes, 2596 old->extent_offset + old->offset + old->len); 2597 len -= max(backref->extent_offset, old->extent_offset + old->offset); 2598 2599 ret = btrfs_drop_extents(trans, root, inode, start, 2600 start + len, 1); 2601 if (ret) 2602 goto out_free_path; 2603 again: 2604 key.objectid = btrfs_ino(BTRFS_I(inode)); 2605 key.type = BTRFS_EXTENT_DATA_KEY; 2606 key.offset = start; 2607 2608 path->leave_spinning = 1; 2609 if (merge) { 2610 struct btrfs_file_extent_item *fi; 2611 u64 extent_len; 2612 struct btrfs_key found_key; 2613 2614 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2615 if (ret < 0) 2616 goto out_free_path; 2617 2618 path->slots[0]--; 2619 leaf = path->nodes[0]; 2620 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2621 2622 fi = btrfs_item_ptr(leaf, path->slots[0], 2623 struct btrfs_file_extent_item); 2624 extent_len = btrfs_file_extent_num_bytes(leaf, fi); 2625 2626 if (extent_len + found_key.offset == start && 2627 relink_is_mergable(leaf, fi, new)) { 2628 btrfs_set_file_extent_num_bytes(leaf, fi, 2629 extent_len + len); 2630 btrfs_mark_buffer_dirty(leaf); 2631 inode_add_bytes(inode, len); 2632 2633 ret = 1; 2634 goto out_free_path; 2635 } else { 2636 merge = false; 2637 btrfs_release_path(path); 2638 goto again; 2639 } 2640 } 2641 2642 ret = btrfs_insert_empty_item(trans, root, path, &key, 2643 sizeof(*extent)); 2644 if (ret) { 2645 btrfs_abort_transaction(trans, ret); 2646 goto out_free_path; 2647 } 2648 2649 leaf = path->nodes[0]; 2650 item = btrfs_item_ptr(leaf, path->slots[0], 2651 struct btrfs_file_extent_item); 2652 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr); 2653 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len); 2654 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos); 2655 btrfs_set_file_extent_num_bytes(leaf, item, len); 2656 btrfs_set_file_extent_ram_bytes(leaf, item, new->len); 2657 btrfs_set_file_extent_generation(leaf, item, trans->transid); 2658 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG); 2659 btrfs_set_file_extent_compression(leaf, item, new->compress_type); 2660 btrfs_set_file_extent_encryption(leaf, item, 0); 2661 btrfs_set_file_extent_other_encoding(leaf, item, 0); 2662 2663 btrfs_mark_buffer_dirty(leaf); 2664 inode_add_bytes(inode, len); 2665 btrfs_release_path(path); 2666 2667 ret = btrfs_inc_extent_ref(trans, fs_info, new->bytenr, 2668 new->disk_len, 0, 2669 backref->root_id, backref->inum, 2670 new->file_pos); /* start - extent_offset */ 2671 if (ret) { 2672 btrfs_abort_transaction(trans, ret); 2673 goto out_free_path; 2674 } 2675 2676 ret = 1; 2677 out_free_path: 2678 btrfs_release_path(path); 2679 path->leave_spinning = 0; 2680 btrfs_end_transaction(trans); 2681 out_unlock: 2682 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end, 2683 &cached, GFP_NOFS); 2684 iput(inode); 2685 return ret; 2686 } 2687 2688 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new) 2689 { 2690 struct old_sa_defrag_extent *old, *tmp; 2691 2692 if (!new) 2693 return; 2694 2695 list_for_each_entry_safe(old, tmp, &new->head, list) { 2696 kfree(old); 2697 } 2698 kfree(new); 2699 } 2700 2701 static void relink_file_extents(struct new_sa_defrag_extent *new) 2702 { 2703 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); 2704 struct btrfs_path *path; 2705 struct sa_defrag_extent_backref *backref; 2706 struct sa_defrag_extent_backref *prev = NULL; 2707 struct inode *inode; 2708 struct btrfs_root *root; 2709 struct rb_node *node; 2710 int ret; 2711 2712 inode = new->inode; 2713 root = BTRFS_I(inode)->root; 2714 2715 path = btrfs_alloc_path(); 2716 if (!path) 2717 return; 2718 2719 if (!record_extent_backrefs(path, new)) { 2720 btrfs_free_path(path); 2721 goto out; 2722 } 2723 btrfs_release_path(path); 2724 2725 while (1) { 2726 node = rb_first(&new->root); 2727 if (!node) 2728 break; 2729 rb_erase(node, &new->root); 2730 2731 backref = rb_entry(node, struct sa_defrag_extent_backref, node); 2732 2733 ret = relink_extent_backref(path, prev, backref); 2734 WARN_ON(ret < 0); 2735 2736 kfree(prev); 2737 2738 if (ret == 1) 2739 prev = backref; 2740 else 2741 prev = NULL; 2742 cond_resched(); 2743 } 2744 kfree(prev); 2745 2746 btrfs_free_path(path); 2747 out: 2748 free_sa_defrag_extent(new); 2749 2750 atomic_dec(&fs_info->defrag_running); 2751 wake_up(&fs_info->transaction_wait); 2752 } 2753 2754 static struct new_sa_defrag_extent * 2755 record_old_file_extents(struct inode *inode, 2756 struct btrfs_ordered_extent *ordered) 2757 { 2758 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2759 struct btrfs_root *root = BTRFS_I(inode)->root; 2760 struct btrfs_path *path; 2761 struct btrfs_key key; 2762 struct old_sa_defrag_extent *old; 2763 struct new_sa_defrag_extent *new; 2764 int ret; 2765 2766 new = kmalloc(sizeof(*new), GFP_NOFS); 2767 if (!new) 2768 return NULL; 2769 2770 new->inode = inode; 2771 new->file_pos = ordered->file_offset; 2772 new->len = ordered->len; 2773 new->bytenr = ordered->start; 2774 new->disk_len = ordered->disk_len; 2775 new->compress_type = ordered->compress_type; 2776 new->root = RB_ROOT; 2777 INIT_LIST_HEAD(&new->head); 2778 2779 path = btrfs_alloc_path(); 2780 if (!path) 2781 goto out_kfree; 2782 2783 key.objectid = btrfs_ino(BTRFS_I(inode)); 2784 key.type = BTRFS_EXTENT_DATA_KEY; 2785 key.offset = new->file_pos; 2786 2787 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2788 if (ret < 0) 2789 goto out_free_path; 2790 if (ret > 0 && path->slots[0] > 0) 2791 path->slots[0]--; 2792 2793 /* find out all the old extents for the file range */ 2794 while (1) { 2795 struct btrfs_file_extent_item *extent; 2796 struct extent_buffer *l; 2797 int slot; 2798 u64 num_bytes; 2799 u64 offset; 2800 u64 end; 2801 u64 disk_bytenr; 2802 u64 extent_offset; 2803 2804 l = path->nodes[0]; 2805 slot = path->slots[0]; 2806 2807 if (slot >= btrfs_header_nritems(l)) { 2808 ret = btrfs_next_leaf(root, path); 2809 if (ret < 0) 2810 goto out_free_path; 2811 else if (ret > 0) 2812 break; 2813 continue; 2814 } 2815 2816 btrfs_item_key_to_cpu(l, &key, slot); 2817 2818 if (key.objectid != btrfs_ino(BTRFS_I(inode))) 2819 break; 2820 if (key.type != BTRFS_EXTENT_DATA_KEY) 2821 break; 2822 if (key.offset >= new->file_pos + new->len) 2823 break; 2824 2825 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item); 2826 2827 num_bytes = btrfs_file_extent_num_bytes(l, extent); 2828 if (key.offset + num_bytes < new->file_pos) 2829 goto next; 2830 2831 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent); 2832 if (!disk_bytenr) 2833 goto next; 2834 2835 extent_offset = btrfs_file_extent_offset(l, extent); 2836 2837 old = kmalloc(sizeof(*old), GFP_NOFS); 2838 if (!old) 2839 goto out_free_path; 2840 2841 offset = max(new->file_pos, key.offset); 2842 end = min(new->file_pos + new->len, key.offset + num_bytes); 2843 2844 old->bytenr = disk_bytenr; 2845 old->extent_offset = extent_offset; 2846 old->offset = offset - key.offset; 2847 old->len = end - offset; 2848 old->new = new; 2849 old->count = 0; 2850 list_add_tail(&old->list, &new->head); 2851 next: 2852 path->slots[0]++; 2853 cond_resched(); 2854 } 2855 2856 btrfs_free_path(path); 2857 atomic_inc(&fs_info->defrag_running); 2858 2859 return new; 2860 2861 out_free_path: 2862 btrfs_free_path(path); 2863 out_kfree: 2864 free_sa_defrag_extent(new); 2865 return NULL; 2866 } 2867 2868 static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info, 2869 u64 start, u64 len) 2870 { 2871 struct btrfs_block_group_cache *cache; 2872 2873 cache = btrfs_lookup_block_group(fs_info, start); 2874 ASSERT(cache); 2875 2876 spin_lock(&cache->lock); 2877 cache->delalloc_bytes -= len; 2878 spin_unlock(&cache->lock); 2879 2880 btrfs_put_block_group(cache); 2881 } 2882 2883 /* as ordered data IO finishes, this gets called so we can finish 2884 * an ordered extent if the range of bytes in the file it covers are 2885 * fully written. 2886 */ 2887 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent) 2888 { 2889 struct inode *inode = ordered_extent->inode; 2890 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2891 struct btrfs_root *root = BTRFS_I(inode)->root; 2892 struct btrfs_trans_handle *trans = NULL; 2893 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 2894 struct extent_state *cached_state = NULL; 2895 struct new_sa_defrag_extent *new = NULL; 2896 int compress_type = 0; 2897 int ret = 0; 2898 u64 logical_len = ordered_extent->len; 2899 bool nolock; 2900 bool truncated = false; 2901 bool range_locked = false; 2902 bool clear_new_delalloc_bytes = false; 2903 2904 if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && 2905 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) && 2906 !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags)) 2907 clear_new_delalloc_bytes = true; 2908 2909 nolock = btrfs_is_free_space_inode(BTRFS_I(inode)); 2910 2911 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) { 2912 ret = -EIO; 2913 goto out; 2914 } 2915 2916 btrfs_free_io_failure_record(BTRFS_I(inode), 2917 ordered_extent->file_offset, 2918 ordered_extent->file_offset + 2919 ordered_extent->len - 1); 2920 2921 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) { 2922 truncated = true; 2923 logical_len = ordered_extent->truncated_len; 2924 /* Truncated the entire extent, don't bother adding */ 2925 if (!logical_len) 2926 goto out; 2927 } 2928 2929 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { 2930 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */ 2931 2932 /* 2933 * For mwrite(mmap + memset to write) case, we still reserve 2934 * space for NOCOW range. 2935 * As NOCOW won't cause a new delayed ref, just free the space 2936 */ 2937 btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset, 2938 ordered_extent->len); 2939 btrfs_ordered_update_i_size(inode, 0, ordered_extent); 2940 if (nolock) 2941 trans = btrfs_join_transaction_nolock(root); 2942 else 2943 trans = btrfs_join_transaction(root); 2944 if (IS_ERR(trans)) { 2945 ret = PTR_ERR(trans); 2946 trans = NULL; 2947 goto out; 2948 } 2949 trans->block_rsv = &fs_info->delalloc_block_rsv; 2950 ret = btrfs_update_inode_fallback(trans, root, inode); 2951 if (ret) /* -ENOMEM or corruption */ 2952 btrfs_abort_transaction(trans, ret); 2953 goto out; 2954 } 2955 2956 range_locked = true; 2957 lock_extent_bits(io_tree, ordered_extent->file_offset, 2958 ordered_extent->file_offset + ordered_extent->len - 1, 2959 &cached_state); 2960 2961 ret = test_range_bit(io_tree, ordered_extent->file_offset, 2962 ordered_extent->file_offset + ordered_extent->len - 1, 2963 EXTENT_DEFRAG, 0, cached_state); 2964 if (ret) { 2965 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item); 2966 if (0 && last_snapshot >= BTRFS_I(inode)->generation) 2967 /* the inode is shared */ 2968 new = record_old_file_extents(inode, ordered_extent); 2969 2970 clear_extent_bit(io_tree, ordered_extent->file_offset, 2971 ordered_extent->file_offset + ordered_extent->len - 1, 2972 EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS); 2973 } 2974 2975 if (nolock) 2976 trans = btrfs_join_transaction_nolock(root); 2977 else 2978 trans = btrfs_join_transaction(root); 2979 if (IS_ERR(trans)) { 2980 ret = PTR_ERR(trans); 2981 trans = NULL; 2982 goto out; 2983 } 2984 2985 trans->block_rsv = &fs_info->delalloc_block_rsv; 2986 2987 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) 2988 compress_type = ordered_extent->compress_type; 2989 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { 2990 BUG_ON(compress_type); 2991 ret = btrfs_mark_extent_written(trans, BTRFS_I(inode), 2992 ordered_extent->file_offset, 2993 ordered_extent->file_offset + 2994 logical_len); 2995 } else { 2996 BUG_ON(root == fs_info->tree_root); 2997 ret = insert_reserved_file_extent(trans, inode, 2998 ordered_extent->file_offset, 2999 ordered_extent->start, 3000 ordered_extent->disk_len, 3001 logical_len, logical_len, 3002 compress_type, 0, 0, 3003 BTRFS_FILE_EXTENT_REG); 3004 if (!ret) 3005 btrfs_release_delalloc_bytes(fs_info, 3006 ordered_extent->start, 3007 ordered_extent->disk_len); 3008 } 3009 unpin_extent_cache(&BTRFS_I(inode)->extent_tree, 3010 ordered_extent->file_offset, ordered_extent->len, 3011 trans->transid); 3012 if (ret < 0) { 3013 btrfs_abort_transaction(trans, ret); 3014 goto out; 3015 } 3016 3017 add_pending_csums(trans, inode, &ordered_extent->list); 3018 3019 btrfs_ordered_update_i_size(inode, 0, ordered_extent); 3020 ret = btrfs_update_inode_fallback(trans, root, inode); 3021 if (ret) { /* -ENOMEM or corruption */ 3022 btrfs_abort_transaction(trans, ret); 3023 goto out; 3024 } 3025 ret = 0; 3026 out: 3027 if (range_locked || clear_new_delalloc_bytes) { 3028 unsigned int clear_bits = 0; 3029 3030 if (range_locked) 3031 clear_bits |= EXTENT_LOCKED; 3032 if (clear_new_delalloc_bytes) 3033 clear_bits |= EXTENT_DELALLOC_NEW; 3034 clear_extent_bit(&BTRFS_I(inode)->io_tree, 3035 ordered_extent->file_offset, 3036 ordered_extent->file_offset + 3037 ordered_extent->len - 1, 3038 clear_bits, 3039 (clear_bits & EXTENT_LOCKED) ? 1 : 0, 3040 0, &cached_state, GFP_NOFS); 3041 } 3042 3043 if (root != fs_info->tree_root) 3044 btrfs_delalloc_release_metadata(BTRFS_I(inode), 3045 ordered_extent->len); 3046 if (trans) 3047 btrfs_end_transaction(trans); 3048 3049 if (ret || truncated) { 3050 u64 start, end; 3051 3052 if (truncated) 3053 start = ordered_extent->file_offset + logical_len; 3054 else 3055 start = ordered_extent->file_offset; 3056 end = ordered_extent->file_offset + ordered_extent->len - 1; 3057 clear_extent_uptodate(io_tree, start, end, NULL, GFP_NOFS); 3058 3059 /* Drop the cache for the part of the extent we didn't write. */ 3060 btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); 3061 3062 /* 3063 * If the ordered extent had an IOERR or something else went 3064 * wrong we need to return the space for this ordered extent 3065 * back to the allocator. We only free the extent in the 3066 * truncated case if we didn't write out the extent at all. 3067 */ 3068 if ((ret || !logical_len) && 3069 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && 3070 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) 3071 btrfs_free_reserved_extent(fs_info, 3072 ordered_extent->start, 3073 ordered_extent->disk_len, 1); 3074 } 3075 3076 3077 /* 3078 * This needs to be done to make sure anybody waiting knows we are done 3079 * updating everything for this ordered extent. 3080 */ 3081 btrfs_remove_ordered_extent(inode, ordered_extent); 3082 3083 /* for snapshot-aware defrag */ 3084 if (new) { 3085 if (ret) { 3086 free_sa_defrag_extent(new); 3087 atomic_dec(&fs_info->defrag_running); 3088 } else { 3089 relink_file_extents(new); 3090 } 3091 } 3092 3093 /* once for us */ 3094 btrfs_put_ordered_extent(ordered_extent); 3095 /* once for the tree */ 3096 btrfs_put_ordered_extent(ordered_extent); 3097 3098 return ret; 3099 } 3100 3101 static void finish_ordered_fn(struct btrfs_work *work) 3102 { 3103 struct btrfs_ordered_extent *ordered_extent; 3104 ordered_extent = container_of(work, struct btrfs_ordered_extent, work); 3105 btrfs_finish_ordered_io(ordered_extent); 3106 } 3107 3108 static void btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, 3109 struct extent_state *state, int uptodate) 3110 { 3111 struct inode *inode = page->mapping->host; 3112 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3113 struct btrfs_ordered_extent *ordered_extent = NULL; 3114 struct btrfs_workqueue *wq; 3115 btrfs_work_func_t func; 3116 3117 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); 3118 3119 ClearPagePrivate2(page); 3120 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start, 3121 end - start + 1, uptodate)) 3122 return; 3123 3124 if (btrfs_is_free_space_inode(BTRFS_I(inode))) { 3125 wq = fs_info->endio_freespace_worker; 3126 func = btrfs_freespace_write_helper; 3127 } else { 3128 wq = fs_info->endio_write_workers; 3129 func = btrfs_endio_write_helper; 3130 } 3131 3132 btrfs_init_work(&ordered_extent->work, func, finish_ordered_fn, NULL, 3133 NULL); 3134 btrfs_queue_work(wq, &ordered_extent->work); 3135 } 3136 3137 static int __readpage_endio_check(struct inode *inode, 3138 struct btrfs_io_bio *io_bio, 3139 int icsum, struct page *page, 3140 int pgoff, u64 start, size_t len) 3141 { 3142 char *kaddr; 3143 u32 csum_expected; 3144 u32 csum = ~(u32)0; 3145 3146 csum_expected = *(((u32 *)io_bio->csum) + icsum); 3147 3148 kaddr = kmap_atomic(page); 3149 csum = btrfs_csum_data(kaddr + pgoff, csum, len); 3150 btrfs_csum_final(csum, (u8 *)&csum); 3151 if (csum != csum_expected) 3152 goto zeroit; 3153 3154 kunmap_atomic(kaddr); 3155 return 0; 3156 zeroit: 3157 btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected, 3158 io_bio->mirror_num); 3159 memset(kaddr + pgoff, 1, len); 3160 flush_dcache_page(page); 3161 kunmap_atomic(kaddr); 3162 if (csum_expected == 0) 3163 return 0; 3164 return -EIO; 3165 } 3166 3167 /* 3168 * when reads are done, we need to check csums to verify the data is correct 3169 * if there's a match, we allow the bio to finish. If not, the code in 3170 * extent_io.c will try to find good copies for us. 3171 */ 3172 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio, 3173 u64 phy_offset, struct page *page, 3174 u64 start, u64 end, int mirror) 3175 { 3176 size_t offset = start - page_offset(page); 3177 struct inode *inode = page->mapping->host; 3178 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 3179 struct btrfs_root *root = BTRFS_I(inode)->root; 3180 3181 if (PageChecked(page)) { 3182 ClearPageChecked(page); 3183 return 0; 3184 } 3185 3186 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) 3187 return 0; 3188 3189 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && 3190 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { 3191 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM); 3192 return 0; 3193 } 3194 3195 phy_offset >>= inode->i_sb->s_blocksize_bits; 3196 return __readpage_endio_check(inode, io_bio, phy_offset, page, offset, 3197 start, (size_t)(end - start + 1)); 3198 } 3199 3200 void btrfs_add_delayed_iput(struct inode *inode) 3201 { 3202 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3203 struct btrfs_inode *binode = BTRFS_I(inode); 3204 3205 if (atomic_add_unless(&inode->i_count, -1, 1)) 3206 return; 3207 3208 spin_lock(&fs_info->delayed_iput_lock); 3209 if (binode->delayed_iput_count == 0) { 3210 ASSERT(list_empty(&binode->delayed_iput)); 3211 list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs); 3212 } else { 3213 binode->delayed_iput_count++; 3214 } 3215 spin_unlock(&fs_info->delayed_iput_lock); 3216 } 3217 3218 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info) 3219 { 3220 3221 spin_lock(&fs_info->delayed_iput_lock); 3222 while (!list_empty(&fs_info->delayed_iputs)) { 3223 struct btrfs_inode *inode; 3224 3225 inode = list_first_entry(&fs_info->delayed_iputs, 3226 struct btrfs_inode, delayed_iput); 3227 if (inode->delayed_iput_count) { 3228 inode->delayed_iput_count--; 3229 list_move_tail(&inode->delayed_iput, 3230 &fs_info->delayed_iputs); 3231 } else { 3232 list_del_init(&inode->delayed_iput); 3233 } 3234 spin_unlock(&fs_info->delayed_iput_lock); 3235 iput(&inode->vfs_inode); 3236 spin_lock(&fs_info->delayed_iput_lock); 3237 } 3238 spin_unlock(&fs_info->delayed_iput_lock); 3239 } 3240 3241 /* 3242 * This is called in transaction commit time. If there are no orphan 3243 * files in the subvolume, it removes orphan item and frees block_rsv 3244 * structure. 3245 */ 3246 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans, 3247 struct btrfs_root *root) 3248 { 3249 struct btrfs_fs_info *fs_info = root->fs_info; 3250 struct btrfs_block_rsv *block_rsv; 3251 int ret; 3252 3253 if (atomic_read(&root->orphan_inodes) || 3254 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) 3255 return; 3256 3257 spin_lock(&root->orphan_lock); 3258 if (atomic_read(&root->orphan_inodes)) { 3259 spin_unlock(&root->orphan_lock); 3260 return; 3261 } 3262 3263 if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) { 3264 spin_unlock(&root->orphan_lock); 3265 return; 3266 } 3267 3268 block_rsv = root->orphan_block_rsv; 3269 root->orphan_block_rsv = NULL; 3270 spin_unlock(&root->orphan_lock); 3271 3272 if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state) && 3273 btrfs_root_refs(&root->root_item) > 0) { 3274 ret = btrfs_del_orphan_item(trans, fs_info->tree_root, 3275 root->root_key.objectid); 3276 if (ret) 3277 btrfs_abort_transaction(trans, ret); 3278 else 3279 clear_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, 3280 &root->state); 3281 } 3282 3283 if (block_rsv) { 3284 WARN_ON(block_rsv->size > 0); 3285 btrfs_free_block_rsv(fs_info, block_rsv); 3286 } 3287 } 3288 3289 /* 3290 * This creates an orphan entry for the given inode in case something goes 3291 * wrong in the middle of an unlink/truncate. 3292 * 3293 * NOTE: caller of this function should reserve 5 units of metadata for 3294 * this function. 3295 */ 3296 int btrfs_orphan_add(struct btrfs_trans_handle *trans, 3297 struct btrfs_inode *inode) 3298 { 3299 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb); 3300 struct btrfs_root *root = inode->root; 3301 struct btrfs_block_rsv *block_rsv = NULL; 3302 int reserve = 0; 3303 int insert = 0; 3304 int ret; 3305 3306 if (!root->orphan_block_rsv) { 3307 block_rsv = btrfs_alloc_block_rsv(fs_info, 3308 BTRFS_BLOCK_RSV_TEMP); 3309 if (!block_rsv) 3310 return -ENOMEM; 3311 } 3312 3313 spin_lock(&root->orphan_lock); 3314 if (!root->orphan_block_rsv) { 3315 root->orphan_block_rsv = block_rsv; 3316 } else if (block_rsv) { 3317 btrfs_free_block_rsv(fs_info, block_rsv); 3318 block_rsv = NULL; 3319 } 3320 3321 if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3322 &inode->runtime_flags)) { 3323 #if 0 3324 /* 3325 * For proper ENOSPC handling, we should do orphan 3326 * cleanup when mounting. But this introduces backward 3327 * compatibility issue. 3328 */ 3329 if (!xchg(&root->orphan_item_inserted, 1)) 3330 insert = 2; 3331 else 3332 insert = 1; 3333 #endif 3334 insert = 1; 3335 atomic_inc(&root->orphan_inodes); 3336 } 3337 3338 if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3339 &inode->runtime_flags)) 3340 reserve = 1; 3341 spin_unlock(&root->orphan_lock); 3342 3343 /* grab metadata reservation from transaction handle */ 3344 if (reserve) { 3345 ret = btrfs_orphan_reserve_metadata(trans, inode); 3346 ASSERT(!ret); 3347 if (ret) { 3348 atomic_dec(&root->orphan_inodes); 3349 clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3350 &inode->runtime_flags); 3351 if (insert) 3352 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3353 &inode->runtime_flags); 3354 return ret; 3355 } 3356 } 3357 3358 /* insert an orphan item to track this unlinked/truncated file */ 3359 if (insert >= 1) { 3360 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode)); 3361 if (ret) { 3362 atomic_dec(&root->orphan_inodes); 3363 if (reserve) { 3364 clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3365 &inode->runtime_flags); 3366 btrfs_orphan_release_metadata(inode); 3367 } 3368 if (ret != -EEXIST) { 3369 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3370 &inode->runtime_flags); 3371 btrfs_abort_transaction(trans, ret); 3372 return ret; 3373 } 3374 } 3375 ret = 0; 3376 } 3377 3378 /* insert an orphan item to track subvolume contains orphan files */ 3379 if (insert >= 2) { 3380 ret = btrfs_insert_orphan_item(trans, fs_info->tree_root, 3381 root->root_key.objectid); 3382 if (ret && ret != -EEXIST) { 3383 btrfs_abort_transaction(trans, ret); 3384 return ret; 3385 } 3386 } 3387 return 0; 3388 } 3389 3390 /* 3391 * We have done the truncate/delete so we can go ahead and remove the orphan 3392 * item for this particular inode. 3393 */ 3394 static int btrfs_orphan_del(struct btrfs_trans_handle *trans, 3395 struct btrfs_inode *inode) 3396 { 3397 struct btrfs_root *root = inode->root; 3398 int delete_item = 0; 3399 int release_rsv = 0; 3400 int ret = 0; 3401 3402 spin_lock(&root->orphan_lock); 3403 if (test_and_clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3404 &inode->runtime_flags)) 3405 delete_item = 1; 3406 3407 if (test_and_clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3408 &inode->runtime_flags)) 3409 release_rsv = 1; 3410 spin_unlock(&root->orphan_lock); 3411 3412 if (delete_item) { 3413 atomic_dec(&root->orphan_inodes); 3414 if (trans) 3415 ret = btrfs_del_orphan_item(trans, root, 3416 btrfs_ino(inode)); 3417 } 3418 3419 if (release_rsv) 3420 btrfs_orphan_release_metadata(inode); 3421 3422 return ret; 3423 } 3424 3425 /* 3426 * this cleans up any orphans that may be left on the list from the last use 3427 * of this root. 3428 */ 3429 int btrfs_orphan_cleanup(struct btrfs_root *root) 3430 { 3431 struct btrfs_fs_info *fs_info = root->fs_info; 3432 struct btrfs_path *path; 3433 struct extent_buffer *leaf; 3434 struct btrfs_key key, found_key; 3435 struct btrfs_trans_handle *trans; 3436 struct inode *inode; 3437 u64 last_objectid = 0; 3438 int ret = 0, nr_unlink = 0, nr_truncate = 0; 3439 3440 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED)) 3441 return 0; 3442 3443 path = btrfs_alloc_path(); 3444 if (!path) { 3445 ret = -ENOMEM; 3446 goto out; 3447 } 3448 path->reada = READA_BACK; 3449 3450 key.objectid = BTRFS_ORPHAN_OBJECTID; 3451 key.type = BTRFS_ORPHAN_ITEM_KEY; 3452 key.offset = (u64)-1; 3453 3454 while (1) { 3455 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3456 if (ret < 0) 3457 goto out; 3458 3459 /* 3460 * if ret == 0 means we found what we were searching for, which 3461 * is weird, but possible, so only screw with path if we didn't 3462 * find the key and see if we have stuff that matches 3463 */ 3464 if (ret > 0) { 3465 ret = 0; 3466 if (path->slots[0] == 0) 3467 break; 3468 path->slots[0]--; 3469 } 3470 3471 /* pull out the item */ 3472 leaf = path->nodes[0]; 3473 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 3474 3475 /* make sure the item matches what we want */ 3476 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) 3477 break; 3478 if (found_key.type != BTRFS_ORPHAN_ITEM_KEY) 3479 break; 3480 3481 /* release the path since we're done with it */ 3482 btrfs_release_path(path); 3483 3484 /* 3485 * this is where we are basically btrfs_lookup, without the 3486 * crossing root thing. we store the inode number in the 3487 * offset of the orphan item. 3488 */ 3489 3490 if (found_key.offset == last_objectid) { 3491 btrfs_err(fs_info, 3492 "Error removing orphan entry, stopping orphan cleanup"); 3493 ret = -EINVAL; 3494 goto out; 3495 } 3496 3497 last_objectid = found_key.offset; 3498 3499 found_key.objectid = found_key.offset; 3500 found_key.type = BTRFS_INODE_ITEM_KEY; 3501 found_key.offset = 0; 3502 inode = btrfs_iget(fs_info->sb, &found_key, root, NULL); 3503 ret = PTR_ERR_OR_ZERO(inode); 3504 if (ret && ret != -ENOENT) 3505 goto out; 3506 3507 if (ret == -ENOENT && root == fs_info->tree_root) { 3508 struct btrfs_root *dead_root; 3509 struct btrfs_fs_info *fs_info = root->fs_info; 3510 int is_dead_root = 0; 3511 3512 /* 3513 * this is an orphan in the tree root. Currently these 3514 * could come from 2 sources: 3515 * a) a snapshot deletion in progress 3516 * b) a free space cache inode 3517 * We need to distinguish those two, as the snapshot 3518 * orphan must not get deleted. 3519 * find_dead_roots already ran before us, so if this 3520 * is a snapshot deletion, we should find the root 3521 * in the dead_roots list 3522 */ 3523 spin_lock(&fs_info->trans_lock); 3524 list_for_each_entry(dead_root, &fs_info->dead_roots, 3525 root_list) { 3526 if (dead_root->root_key.objectid == 3527 found_key.objectid) { 3528 is_dead_root = 1; 3529 break; 3530 } 3531 } 3532 spin_unlock(&fs_info->trans_lock); 3533 if (is_dead_root) { 3534 /* prevent this orphan from being found again */ 3535 key.offset = found_key.objectid - 1; 3536 continue; 3537 } 3538 } 3539 /* 3540 * Inode is already gone but the orphan item is still there, 3541 * kill the orphan item. 3542 */ 3543 if (ret == -ENOENT) { 3544 trans = btrfs_start_transaction(root, 1); 3545 if (IS_ERR(trans)) { 3546 ret = PTR_ERR(trans); 3547 goto out; 3548 } 3549 btrfs_debug(fs_info, "auto deleting %Lu", 3550 found_key.objectid); 3551 ret = btrfs_del_orphan_item(trans, root, 3552 found_key.objectid); 3553 btrfs_end_transaction(trans); 3554 if (ret) 3555 goto out; 3556 continue; 3557 } 3558 3559 /* 3560 * add this inode to the orphan list so btrfs_orphan_del does 3561 * the proper thing when we hit it 3562 */ 3563 set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3564 &BTRFS_I(inode)->runtime_flags); 3565 atomic_inc(&root->orphan_inodes); 3566 3567 /* if we have links, this was a truncate, lets do that */ 3568 if (inode->i_nlink) { 3569 if (WARN_ON(!S_ISREG(inode->i_mode))) { 3570 iput(inode); 3571 continue; 3572 } 3573 nr_truncate++; 3574 3575 /* 1 for the orphan item deletion. */ 3576 trans = btrfs_start_transaction(root, 1); 3577 if (IS_ERR(trans)) { 3578 iput(inode); 3579 ret = PTR_ERR(trans); 3580 goto out; 3581 } 3582 ret = btrfs_orphan_add(trans, BTRFS_I(inode)); 3583 btrfs_end_transaction(trans); 3584 if (ret) { 3585 iput(inode); 3586 goto out; 3587 } 3588 3589 ret = btrfs_truncate(inode); 3590 if (ret) 3591 btrfs_orphan_del(NULL, BTRFS_I(inode)); 3592 } else { 3593 nr_unlink++; 3594 } 3595 3596 /* this will do delete_inode and everything for us */ 3597 iput(inode); 3598 if (ret) 3599 goto out; 3600 } 3601 /* release the path since we're done with it */ 3602 btrfs_release_path(path); 3603 3604 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE; 3605 3606 if (root->orphan_block_rsv) 3607 btrfs_block_rsv_release(fs_info, root->orphan_block_rsv, 3608 (u64)-1); 3609 3610 if (root->orphan_block_rsv || 3611 test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) { 3612 trans = btrfs_join_transaction(root); 3613 if (!IS_ERR(trans)) 3614 btrfs_end_transaction(trans); 3615 } 3616 3617 if (nr_unlink) 3618 btrfs_debug(fs_info, "unlinked %d orphans", nr_unlink); 3619 if (nr_truncate) 3620 btrfs_debug(fs_info, "truncated %d orphans", nr_truncate); 3621 3622 out: 3623 if (ret) 3624 btrfs_err(fs_info, "could not do orphan cleanup %d", ret); 3625 btrfs_free_path(path); 3626 return ret; 3627 } 3628 3629 /* 3630 * very simple check to peek ahead in the leaf looking for xattrs. If we 3631 * don't find any xattrs, we know there can't be any acls. 3632 * 3633 * slot is the slot the inode is in, objectid is the objectid of the inode 3634 */ 3635 static noinline int acls_after_inode_item(struct extent_buffer *leaf, 3636 int slot, u64 objectid, 3637 int *first_xattr_slot) 3638 { 3639 u32 nritems = btrfs_header_nritems(leaf); 3640 struct btrfs_key found_key; 3641 static u64 xattr_access = 0; 3642 static u64 xattr_default = 0; 3643 int scanned = 0; 3644 3645 if (!xattr_access) { 3646 xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS, 3647 strlen(XATTR_NAME_POSIX_ACL_ACCESS)); 3648 xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT, 3649 strlen(XATTR_NAME_POSIX_ACL_DEFAULT)); 3650 } 3651 3652 slot++; 3653 *first_xattr_slot = -1; 3654 while (slot < nritems) { 3655 btrfs_item_key_to_cpu(leaf, &found_key, slot); 3656 3657 /* we found a different objectid, there must not be acls */ 3658 if (found_key.objectid != objectid) 3659 return 0; 3660 3661 /* we found an xattr, assume we've got an acl */ 3662 if (found_key.type == BTRFS_XATTR_ITEM_KEY) { 3663 if (*first_xattr_slot == -1) 3664 *first_xattr_slot = slot; 3665 if (found_key.offset == xattr_access || 3666 found_key.offset == xattr_default) 3667 return 1; 3668 } 3669 3670 /* 3671 * we found a key greater than an xattr key, there can't 3672 * be any acls later on 3673 */ 3674 if (found_key.type > BTRFS_XATTR_ITEM_KEY) 3675 return 0; 3676 3677 slot++; 3678 scanned++; 3679 3680 /* 3681 * it goes inode, inode backrefs, xattrs, extents, 3682 * so if there are a ton of hard links to an inode there can 3683 * be a lot of backrefs. Don't waste time searching too hard, 3684 * this is just an optimization 3685 */ 3686 if (scanned >= 8) 3687 break; 3688 } 3689 /* we hit the end of the leaf before we found an xattr or 3690 * something larger than an xattr. We have to assume the inode 3691 * has acls 3692 */ 3693 if (*first_xattr_slot == -1) 3694 *first_xattr_slot = slot; 3695 return 1; 3696 } 3697 3698 /* 3699 * read an inode from the btree into the in-memory inode 3700 */ 3701 static int btrfs_read_locked_inode(struct inode *inode) 3702 { 3703 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3704 struct btrfs_path *path; 3705 struct extent_buffer *leaf; 3706 struct btrfs_inode_item *inode_item; 3707 struct btrfs_root *root = BTRFS_I(inode)->root; 3708 struct btrfs_key location; 3709 unsigned long ptr; 3710 int maybe_acls; 3711 u32 rdev; 3712 int ret; 3713 bool filled = false; 3714 int first_xattr_slot; 3715 3716 ret = btrfs_fill_inode(inode, &rdev); 3717 if (!ret) 3718 filled = true; 3719 3720 path = btrfs_alloc_path(); 3721 if (!path) { 3722 ret = -ENOMEM; 3723 goto make_bad; 3724 } 3725 3726 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location)); 3727 3728 ret = btrfs_lookup_inode(NULL, root, path, &location, 0); 3729 if (ret) { 3730 if (ret > 0) 3731 ret = -ENOENT; 3732 goto make_bad; 3733 } 3734 3735 leaf = path->nodes[0]; 3736 3737 if (filled) 3738 goto cache_index; 3739 3740 inode_item = btrfs_item_ptr(leaf, path->slots[0], 3741 struct btrfs_inode_item); 3742 inode->i_mode = btrfs_inode_mode(leaf, inode_item); 3743 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item)); 3744 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item)); 3745 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item)); 3746 btrfs_i_size_write(BTRFS_I(inode), btrfs_inode_size(leaf, inode_item)); 3747 3748 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->atime); 3749 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->atime); 3750 3751 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->mtime); 3752 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->mtime); 3753 3754 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime); 3755 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime); 3756 3757 BTRFS_I(inode)->i_otime.tv_sec = 3758 btrfs_timespec_sec(leaf, &inode_item->otime); 3759 BTRFS_I(inode)->i_otime.tv_nsec = 3760 btrfs_timespec_nsec(leaf, &inode_item->otime); 3761 3762 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item)); 3763 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item); 3764 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item); 3765 3766 inode->i_version = btrfs_inode_sequence(leaf, inode_item); 3767 inode->i_generation = BTRFS_I(inode)->generation; 3768 inode->i_rdev = 0; 3769 rdev = btrfs_inode_rdev(leaf, inode_item); 3770 3771 BTRFS_I(inode)->index_cnt = (u64)-1; 3772 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item); 3773 3774 cache_index: 3775 /* 3776 * If we were modified in the current generation and evicted from memory 3777 * and then re-read we need to do a full sync since we don't have any 3778 * idea about which extents were modified before we were evicted from 3779 * cache. 3780 * 3781 * This is required for both inode re-read from disk and delayed inode 3782 * in delayed_nodes_tree. 3783 */ 3784 if (BTRFS_I(inode)->last_trans == fs_info->generation) 3785 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3786 &BTRFS_I(inode)->runtime_flags); 3787 3788 /* 3789 * We don't persist the id of the transaction where an unlink operation 3790 * against the inode was last made. So here we assume the inode might 3791 * have been evicted, and therefore the exact value of last_unlink_trans 3792 * lost, and set it to last_trans to avoid metadata inconsistencies 3793 * between the inode and its parent if the inode is fsync'ed and the log 3794 * replayed. For example, in the scenario: 3795 * 3796 * touch mydir/foo 3797 * ln mydir/foo mydir/bar 3798 * sync 3799 * unlink mydir/bar 3800 * echo 2 > /proc/sys/vm/drop_caches # evicts inode 3801 * xfs_io -c fsync mydir/foo 3802 * <power failure> 3803 * mount fs, triggers fsync log replay 3804 * 3805 * We must make sure that when we fsync our inode foo we also log its 3806 * parent inode, otherwise after log replay the parent still has the 3807 * dentry with the "bar" name but our inode foo has a link count of 1 3808 * and doesn't have an inode ref with the name "bar" anymore. 3809 * 3810 * Setting last_unlink_trans to last_trans is a pessimistic approach, 3811 * but it guarantees correctness at the expense of occasional full 3812 * transaction commits on fsync if our inode is a directory, or if our 3813 * inode is not a directory, logging its parent unnecessarily. 3814 */ 3815 BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans; 3816 3817 path->slots[0]++; 3818 if (inode->i_nlink != 1 || 3819 path->slots[0] >= btrfs_header_nritems(leaf)) 3820 goto cache_acl; 3821 3822 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]); 3823 if (location.objectid != btrfs_ino(BTRFS_I(inode))) 3824 goto cache_acl; 3825 3826 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); 3827 if (location.type == BTRFS_INODE_REF_KEY) { 3828 struct btrfs_inode_ref *ref; 3829 3830 ref = (struct btrfs_inode_ref *)ptr; 3831 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref); 3832 } else if (location.type == BTRFS_INODE_EXTREF_KEY) { 3833 struct btrfs_inode_extref *extref; 3834 3835 extref = (struct btrfs_inode_extref *)ptr; 3836 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf, 3837 extref); 3838 } 3839 cache_acl: 3840 /* 3841 * try to precache a NULL acl entry for files that don't have 3842 * any xattrs or acls 3843 */ 3844 maybe_acls = acls_after_inode_item(leaf, path->slots[0], 3845 btrfs_ino(BTRFS_I(inode)), &first_xattr_slot); 3846 if (first_xattr_slot != -1) { 3847 path->slots[0] = first_xattr_slot; 3848 ret = btrfs_load_inode_props(inode, path); 3849 if (ret) 3850 btrfs_err(fs_info, 3851 "error loading props for ino %llu (root %llu): %d", 3852 btrfs_ino(BTRFS_I(inode)), 3853 root->root_key.objectid, ret); 3854 } 3855 btrfs_free_path(path); 3856 3857 if (!maybe_acls) 3858 cache_no_acl(inode); 3859 3860 switch (inode->i_mode & S_IFMT) { 3861 case S_IFREG: 3862 inode->i_mapping->a_ops = &btrfs_aops; 3863 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 3864 inode->i_fop = &btrfs_file_operations; 3865 inode->i_op = &btrfs_file_inode_operations; 3866 break; 3867 case S_IFDIR: 3868 inode->i_fop = &btrfs_dir_file_operations; 3869 inode->i_op = &btrfs_dir_inode_operations; 3870 break; 3871 case S_IFLNK: 3872 inode->i_op = &btrfs_symlink_inode_operations; 3873 inode_nohighmem(inode); 3874 inode->i_mapping->a_ops = &btrfs_symlink_aops; 3875 break; 3876 default: 3877 inode->i_op = &btrfs_special_inode_operations; 3878 init_special_inode(inode, inode->i_mode, rdev); 3879 break; 3880 } 3881 3882 btrfs_update_iflags(inode); 3883 return 0; 3884 3885 make_bad: 3886 btrfs_free_path(path); 3887 make_bad_inode(inode); 3888 return ret; 3889 } 3890 3891 /* 3892 * given a leaf and an inode, copy the inode fields into the leaf 3893 */ 3894 static void fill_inode_item(struct btrfs_trans_handle *trans, 3895 struct extent_buffer *leaf, 3896 struct btrfs_inode_item *item, 3897 struct inode *inode) 3898 { 3899 struct btrfs_map_token token; 3900 3901 btrfs_init_map_token(&token); 3902 3903 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token); 3904 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token); 3905 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size, 3906 &token); 3907 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token); 3908 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token); 3909 3910 btrfs_set_token_timespec_sec(leaf, &item->atime, 3911 inode->i_atime.tv_sec, &token); 3912 btrfs_set_token_timespec_nsec(leaf, &item->atime, 3913 inode->i_atime.tv_nsec, &token); 3914 3915 btrfs_set_token_timespec_sec(leaf, &item->mtime, 3916 inode->i_mtime.tv_sec, &token); 3917 btrfs_set_token_timespec_nsec(leaf, &item->mtime, 3918 inode->i_mtime.tv_nsec, &token); 3919 3920 btrfs_set_token_timespec_sec(leaf, &item->ctime, 3921 inode->i_ctime.tv_sec, &token); 3922 btrfs_set_token_timespec_nsec(leaf, &item->ctime, 3923 inode->i_ctime.tv_nsec, &token); 3924 3925 btrfs_set_token_timespec_sec(leaf, &item->otime, 3926 BTRFS_I(inode)->i_otime.tv_sec, &token); 3927 btrfs_set_token_timespec_nsec(leaf, &item->otime, 3928 BTRFS_I(inode)->i_otime.tv_nsec, &token); 3929 3930 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode), 3931 &token); 3932 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation, 3933 &token); 3934 btrfs_set_token_inode_sequence(leaf, item, inode->i_version, &token); 3935 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token); 3936 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token); 3937 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token); 3938 btrfs_set_token_inode_block_group(leaf, item, 0, &token); 3939 } 3940 3941 /* 3942 * copy everything in the in-memory inode into the btree. 3943 */ 3944 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans, 3945 struct btrfs_root *root, struct inode *inode) 3946 { 3947 struct btrfs_inode_item *inode_item; 3948 struct btrfs_path *path; 3949 struct extent_buffer *leaf; 3950 int ret; 3951 3952 path = btrfs_alloc_path(); 3953 if (!path) 3954 return -ENOMEM; 3955 3956 path->leave_spinning = 1; 3957 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location, 3958 1); 3959 if (ret) { 3960 if (ret > 0) 3961 ret = -ENOENT; 3962 goto failed; 3963 } 3964 3965 leaf = path->nodes[0]; 3966 inode_item = btrfs_item_ptr(leaf, path->slots[0], 3967 struct btrfs_inode_item); 3968 3969 fill_inode_item(trans, leaf, inode_item, inode); 3970 btrfs_mark_buffer_dirty(leaf); 3971 btrfs_set_inode_last_trans(trans, inode); 3972 ret = 0; 3973 failed: 3974 btrfs_free_path(path); 3975 return ret; 3976 } 3977 3978 /* 3979 * copy everything in the in-memory inode into the btree. 3980 */ 3981 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans, 3982 struct btrfs_root *root, struct inode *inode) 3983 { 3984 struct btrfs_fs_info *fs_info = root->fs_info; 3985 int ret; 3986 3987 /* 3988 * If the inode is a free space inode, we can deadlock during commit 3989 * if we put it into the delayed code. 3990 * 3991 * The data relocation inode should also be directly updated 3992 * without delay 3993 */ 3994 if (!btrfs_is_free_space_inode(BTRFS_I(inode)) 3995 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID 3996 && !test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) { 3997 btrfs_update_root_times(trans, root); 3998 3999 ret = btrfs_delayed_update_inode(trans, root, inode); 4000 if (!ret) 4001 btrfs_set_inode_last_trans(trans, inode); 4002 return ret; 4003 } 4004 4005 return btrfs_update_inode_item(trans, root, inode); 4006 } 4007 4008 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, 4009 struct btrfs_root *root, 4010 struct inode *inode) 4011 { 4012 int ret; 4013 4014 ret = btrfs_update_inode(trans, root, inode); 4015 if (ret == -ENOSPC) 4016 return btrfs_update_inode_item(trans, root, inode); 4017 return ret; 4018 } 4019 4020 /* 4021 * unlink helper that gets used here in inode.c and in the tree logging 4022 * recovery code. It remove a link in a directory with a given name, and 4023 * also drops the back refs in the inode to the directory 4024 */ 4025 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans, 4026 struct btrfs_root *root, 4027 struct btrfs_inode *dir, 4028 struct btrfs_inode *inode, 4029 const char *name, int name_len) 4030 { 4031 struct btrfs_fs_info *fs_info = root->fs_info; 4032 struct btrfs_path *path; 4033 int ret = 0; 4034 struct extent_buffer *leaf; 4035 struct btrfs_dir_item *di; 4036 struct btrfs_key key; 4037 u64 index; 4038 u64 ino = btrfs_ino(inode); 4039 u64 dir_ino = btrfs_ino(dir); 4040 4041 path = btrfs_alloc_path(); 4042 if (!path) { 4043 ret = -ENOMEM; 4044 goto out; 4045 } 4046 4047 path->leave_spinning = 1; 4048 di = btrfs_lookup_dir_item(trans, root, path, dir_ino, 4049 name, name_len, -1); 4050 if (IS_ERR(di)) { 4051 ret = PTR_ERR(di); 4052 goto err; 4053 } 4054 if (!di) { 4055 ret = -ENOENT; 4056 goto err; 4057 } 4058 leaf = path->nodes[0]; 4059 btrfs_dir_item_key_to_cpu(leaf, di, &key); 4060 ret = btrfs_delete_one_dir_name(trans, root, path, di); 4061 if (ret) 4062 goto err; 4063 btrfs_release_path(path); 4064 4065 /* 4066 * If we don't have dir index, we have to get it by looking up 4067 * the inode ref, since we get the inode ref, remove it directly, 4068 * it is unnecessary to do delayed deletion. 4069 * 4070 * But if we have dir index, needn't search inode ref to get it. 4071 * Since the inode ref is close to the inode item, it is better 4072 * that we delay to delete it, and just do this deletion when 4073 * we update the inode item. 4074 */ 4075 if (inode->dir_index) { 4076 ret = btrfs_delayed_delete_inode_ref(inode); 4077 if (!ret) { 4078 index = inode->dir_index; 4079 goto skip_backref; 4080 } 4081 } 4082 4083 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino, 4084 dir_ino, &index); 4085 if (ret) { 4086 btrfs_info(fs_info, 4087 "failed to delete reference to %.*s, inode %llu parent %llu", 4088 name_len, name, ino, dir_ino); 4089 btrfs_abort_transaction(trans, ret); 4090 goto err; 4091 } 4092 skip_backref: 4093 ret = btrfs_delete_delayed_dir_index(trans, fs_info, dir, index); 4094 if (ret) { 4095 btrfs_abort_transaction(trans, ret); 4096 goto err; 4097 } 4098 4099 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, inode, 4100 dir_ino); 4101 if (ret != 0 && ret != -ENOENT) { 4102 btrfs_abort_transaction(trans, ret); 4103 goto err; 4104 } 4105 4106 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, dir, 4107 index); 4108 if (ret == -ENOENT) 4109 ret = 0; 4110 else if (ret) 4111 btrfs_abort_transaction(trans, ret); 4112 err: 4113 btrfs_free_path(path); 4114 if (ret) 4115 goto out; 4116 4117 btrfs_i_size_write(dir, dir->vfs_inode.i_size - name_len * 2); 4118 inode_inc_iversion(&inode->vfs_inode); 4119 inode_inc_iversion(&dir->vfs_inode); 4120 inode->vfs_inode.i_ctime = dir->vfs_inode.i_mtime = 4121 dir->vfs_inode.i_ctime = current_time(&inode->vfs_inode); 4122 ret = btrfs_update_inode(trans, root, &dir->vfs_inode); 4123 out: 4124 return ret; 4125 } 4126 4127 int btrfs_unlink_inode(struct btrfs_trans_handle *trans, 4128 struct btrfs_root *root, 4129 struct btrfs_inode *dir, struct btrfs_inode *inode, 4130 const char *name, int name_len) 4131 { 4132 int ret; 4133 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len); 4134 if (!ret) { 4135 drop_nlink(&inode->vfs_inode); 4136 ret = btrfs_update_inode(trans, root, &inode->vfs_inode); 4137 } 4138 return ret; 4139 } 4140 4141 /* 4142 * helper to start transaction for unlink and rmdir. 4143 * 4144 * unlink and rmdir are special in btrfs, they do not always free space, so 4145 * if we cannot make our reservations the normal way try and see if there is 4146 * plenty of slack room in the global reserve to migrate, otherwise we cannot 4147 * allow the unlink to occur. 4148 */ 4149 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir) 4150 { 4151 struct btrfs_root *root = BTRFS_I(dir)->root; 4152 4153 /* 4154 * 1 for the possible orphan item 4155 * 1 for the dir item 4156 * 1 for the dir index 4157 * 1 for the inode ref 4158 * 1 for the inode 4159 */ 4160 return btrfs_start_transaction_fallback_global_rsv(root, 5, 5); 4161 } 4162 4163 static int btrfs_unlink(struct inode *dir, struct dentry *dentry) 4164 { 4165 struct btrfs_root *root = BTRFS_I(dir)->root; 4166 struct btrfs_trans_handle *trans; 4167 struct inode *inode = d_inode(dentry); 4168 int ret; 4169 4170 trans = __unlink_start_trans(dir); 4171 if (IS_ERR(trans)) 4172 return PTR_ERR(trans); 4173 4174 btrfs_record_unlink_dir(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), 4175 0); 4176 4177 ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir), 4178 BTRFS_I(d_inode(dentry)), dentry->d_name.name, 4179 dentry->d_name.len); 4180 if (ret) 4181 goto out; 4182 4183 if (inode->i_nlink == 0) { 4184 ret = btrfs_orphan_add(trans, BTRFS_I(inode)); 4185 if (ret) 4186 goto out; 4187 } 4188 4189 out: 4190 btrfs_end_transaction(trans); 4191 btrfs_btree_balance_dirty(root->fs_info); 4192 return ret; 4193 } 4194 4195 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, 4196 struct btrfs_root *root, 4197 struct inode *dir, u64 objectid, 4198 const char *name, int name_len) 4199 { 4200 struct btrfs_fs_info *fs_info = root->fs_info; 4201 struct btrfs_path *path; 4202 struct extent_buffer *leaf; 4203 struct btrfs_dir_item *di; 4204 struct btrfs_key key; 4205 u64 index; 4206 int ret; 4207 u64 dir_ino = btrfs_ino(BTRFS_I(dir)); 4208 4209 path = btrfs_alloc_path(); 4210 if (!path) 4211 return -ENOMEM; 4212 4213 di = btrfs_lookup_dir_item(trans, root, path, dir_ino, 4214 name, name_len, -1); 4215 if (IS_ERR_OR_NULL(di)) { 4216 if (!di) 4217 ret = -ENOENT; 4218 else 4219 ret = PTR_ERR(di); 4220 goto out; 4221 } 4222 4223 leaf = path->nodes[0]; 4224 btrfs_dir_item_key_to_cpu(leaf, di, &key); 4225 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); 4226 ret = btrfs_delete_one_dir_name(trans, root, path, di); 4227 if (ret) { 4228 btrfs_abort_transaction(trans, ret); 4229 goto out; 4230 } 4231 btrfs_release_path(path); 4232 4233 ret = btrfs_del_root_ref(trans, fs_info, objectid, 4234 root->root_key.objectid, dir_ino, 4235 &index, name, name_len); 4236 if (ret < 0) { 4237 if (ret != -ENOENT) { 4238 btrfs_abort_transaction(trans, ret); 4239 goto out; 4240 } 4241 di = btrfs_search_dir_index_item(root, path, dir_ino, 4242 name, name_len); 4243 if (IS_ERR_OR_NULL(di)) { 4244 if (!di) 4245 ret = -ENOENT; 4246 else 4247 ret = PTR_ERR(di); 4248 btrfs_abort_transaction(trans, ret); 4249 goto out; 4250 } 4251 4252 leaf = path->nodes[0]; 4253 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 4254 btrfs_release_path(path); 4255 index = key.offset; 4256 } 4257 btrfs_release_path(path); 4258 4259 ret = btrfs_delete_delayed_dir_index(trans, fs_info, BTRFS_I(dir), index); 4260 if (ret) { 4261 btrfs_abort_transaction(trans, ret); 4262 goto out; 4263 } 4264 4265 btrfs_i_size_write(BTRFS_I(dir), dir->i_size - name_len * 2); 4266 inode_inc_iversion(dir); 4267 dir->i_mtime = dir->i_ctime = current_time(dir); 4268 ret = btrfs_update_inode_fallback(trans, root, dir); 4269 if (ret) 4270 btrfs_abort_transaction(trans, ret); 4271 out: 4272 btrfs_free_path(path); 4273 return ret; 4274 } 4275 4276 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) 4277 { 4278 struct inode *inode = d_inode(dentry); 4279 int err = 0; 4280 struct btrfs_root *root = BTRFS_I(dir)->root; 4281 struct btrfs_trans_handle *trans; 4282 u64 last_unlink_trans; 4283 4284 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) 4285 return -ENOTEMPTY; 4286 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID) 4287 return -EPERM; 4288 4289 trans = __unlink_start_trans(dir); 4290 if (IS_ERR(trans)) 4291 return PTR_ERR(trans); 4292 4293 if (unlikely(btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { 4294 err = btrfs_unlink_subvol(trans, root, dir, 4295 BTRFS_I(inode)->location.objectid, 4296 dentry->d_name.name, 4297 dentry->d_name.len); 4298 goto out; 4299 } 4300 4301 err = btrfs_orphan_add(trans, BTRFS_I(inode)); 4302 if (err) 4303 goto out; 4304 4305 last_unlink_trans = BTRFS_I(inode)->last_unlink_trans; 4306 4307 /* now the directory is empty */ 4308 err = btrfs_unlink_inode(trans, root, BTRFS_I(dir), 4309 BTRFS_I(d_inode(dentry)), dentry->d_name.name, 4310 dentry->d_name.len); 4311 if (!err) { 4312 btrfs_i_size_write(BTRFS_I(inode), 0); 4313 /* 4314 * Propagate the last_unlink_trans value of the deleted dir to 4315 * its parent directory. This is to prevent an unrecoverable 4316 * log tree in the case we do something like this: 4317 * 1) create dir foo 4318 * 2) create snapshot under dir foo 4319 * 3) delete the snapshot 4320 * 4) rmdir foo 4321 * 5) mkdir foo 4322 * 6) fsync foo or some file inside foo 4323 */ 4324 if (last_unlink_trans >= trans->transid) 4325 BTRFS_I(dir)->last_unlink_trans = last_unlink_trans; 4326 } 4327 out: 4328 btrfs_end_transaction(trans); 4329 btrfs_btree_balance_dirty(root->fs_info); 4330 4331 return err; 4332 } 4333 4334 static int truncate_space_check(struct btrfs_trans_handle *trans, 4335 struct btrfs_root *root, 4336 u64 bytes_deleted) 4337 { 4338 struct btrfs_fs_info *fs_info = root->fs_info; 4339 int ret; 4340 4341 /* 4342 * This is only used to apply pressure to the enospc system, we don't 4343 * intend to use this reservation at all. 4344 */ 4345 bytes_deleted = btrfs_csum_bytes_to_leaves(fs_info, bytes_deleted); 4346 bytes_deleted *= fs_info->nodesize; 4347 ret = btrfs_block_rsv_add(root, &fs_info->trans_block_rsv, 4348 bytes_deleted, BTRFS_RESERVE_NO_FLUSH); 4349 if (!ret) { 4350 trace_btrfs_space_reservation(fs_info, "transaction", 4351 trans->transid, 4352 bytes_deleted, 1); 4353 trans->bytes_reserved += bytes_deleted; 4354 } 4355 return ret; 4356 4357 } 4358 4359 static int truncate_inline_extent(struct inode *inode, 4360 struct btrfs_path *path, 4361 struct btrfs_key *found_key, 4362 const u64 item_end, 4363 const u64 new_size) 4364 { 4365 struct extent_buffer *leaf = path->nodes[0]; 4366 int slot = path->slots[0]; 4367 struct btrfs_file_extent_item *fi; 4368 u32 size = (u32)(new_size - found_key->offset); 4369 struct btrfs_root *root = BTRFS_I(inode)->root; 4370 4371 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); 4372 4373 if (btrfs_file_extent_compression(leaf, fi) != BTRFS_COMPRESS_NONE) { 4374 loff_t offset = new_size; 4375 loff_t page_end = ALIGN(offset, PAGE_SIZE); 4376 4377 /* 4378 * Zero out the remaining of the last page of our inline extent, 4379 * instead of directly truncating our inline extent here - that 4380 * would be much more complex (decompressing all the data, then 4381 * compressing the truncated data, which might be bigger than 4382 * the size of the inline extent, resize the extent, etc). 4383 * We release the path because to get the page we might need to 4384 * read the extent item from disk (data not in the page cache). 4385 */ 4386 btrfs_release_path(path); 4387 return btrfs_truncate_block(inode, offset, page_end - offset, 4388 0); 4389 } 4390 4391 btrfs_set_file_extent_ram_bytes(leaf, fi, size); 4392 size = btrfs_file_extent_calc_inline_size(size); 4393 btrfs_truncate_item(root->fs_info, path, size, 1); 4394 4395 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4396 inode_sub_bytes(inode, item_end + 1 - new_size); 4397 4398 return 0; 4399 } 4400 4401 /* 4402 * this can truncate away extent items, csum items and directory items. 4403 * It starts at a high offset and removes keys until it can't find 4404 * any higher than new_size 4405 * 4406 * csum items that cross the new i_size are truncated to the new size 4407 * as well. 4408 * 4409 * min_type is the minimum key type to truncate down to. If set to 0, this 4410 * will kill all the items on this inode, including the INODE_ITEM_KEY. 4411 */ 4412 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, 4413 struct btrfs_root *root, 4414 struct inode *inode, 4415 u64 new_size, u32 min_type) 4416 { 4417 struct btrfs_fs_info *fs_info = root->fs_info; 4418 struct btrfs_path *path; 4419 struct extent_buffer *leaf; 4420 struct btrfs_file_extent_item *fi; 4421 struct btrfs_key key; 4422 struct btrfs_key found_key; 4423 u64 extent_start = 0; 4424 u64 extent_num_bytes = 0; 4425 u64 extent_offset = 0; 4426 u64 item_end = 0; 4427 u64 last_size = new_size; 4428 u32 found_type = (u8)-1; 4429 int found_extent; 4430 int del_item; 4431 int pending_del_nr = 0; 4432 int pending_del_slot = 0; 4433 int extent_type = -1; 4434 int ret; 4435 int err = 0; 4436 u64 ino = btrfs_ino(BTRFS_I(inode)); 4437 u64 bytes_deleted = 0; 4438 bool be_nice = 0; 4439 bool should_throttle = 0; 4440 bool should_end = 0; 4441 4442 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); 4443 4444 /* 4445 * for non-free space inodes and ref cows, we want to back off from 4446 * time to time 4447 */ 4448 if (!btrfs_is_free_space_inode(BTRFS_I(inode)) && 4449 test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4450 be_nice = 1; 4451 4452 path = btrfs_alloc_path(); 4453 if (!path) 4454 return -ENOMEM; 4455 path->reada = READA_BACK; 4456 4457 /* 4458 * We want to drop from the next block forward in case this new size is 4459 * not block aligned since we will be keeping the last block of the 4460 * extent just the way it is. 4461 */ 4462 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || 4463 root == fs_info->tree_root) 4464 btrfs_drop_extent_cache(BTRFS_I(inode), ALIGN(new_size, 4465 fs_info->sectorsize), 4466 (u64)-1, 0); 4467 4468 /* 4469 * This function is also used to drop the items in the log tree before 4470 * we relog the inode, so if root != BTRFS_I(inode)->root, it means 4471 * it is used to drop the loged items. So we shouldn't kill the delayed 4472 * items. 4473 */ 4474 if (min_type == 0 && root == BTRFS_I(inode)->root) 4475 btrfs_kill_delayed_inode_items(BTRFS_I(inode)); 4476 4477 key.objectid = ino; 4478 key.offset = (u64)-1; 4479 key.type = (u8)-1; 4480 4481 search_again: 4482 /* 4483 * with a 16K leaf size and 128MB extents, you can actually queue 4484 * up a huge file in a single leaf. Most of the time that 4485 * bytes_deleted is > 0, it will be huge by the time we get here 4486 */ 4487 if (be_nice && bytes_deleted > SZ_32M) { 4488 if (btrfs_should_end_transaction(trans)) { 4489 err = -EAGAIN; 4490 goto error; 4491 } 4492 } 4493 4494 4495 path->leave_spinning = 1; 4496 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 4497 if (ret < 0) { 4498 err = ret; 4499 goto out; 4500 } 4501 4502 if (ret > 0) { 4503 /* there are no items in the tree for us to truncate, we're 4504 * done 4505 */ 4506 if (path->slots[0] == 0) 4507 goto out; 4508 path->slots[0]--; 4509 } 4510 4511 while (1) { 4512 fi = NULL; 4513 leaf = path->nodes[0]; 4514 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 4515 found_type = found_key.type; 4516 4517 if (found_key.objectid != ino) 4518 break; 4519 4520 if (found_type < min_type) 4521 break; 4522 4523 item_end = found_key.offset; 4524 if (found_type == BTRFS_EXTENT_DATA_KEY) { 4525 fi = btrfs_item_ptr(leaf, path->slots[0], 4526 struct btrfs_file_extent_item); 4527 extent_type = btrfs_file_extent_type(leaf, fi); 4528 if (extent_type != BTRFS_FILE_EXTENT_INLINE) { 4529 item_end += 4530 btrfs_file_extent_num_bytes(leaf, fi); 4531 4532 trace_btrfs_truncate_show_fi_regular( 4533 BTRFS_I(inode), leaf, fi, 4534 found_key.offset); 4535 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 4536 item_end += btrfs_file_extent_inline_len(leaf, 4537 path->slots[0], fi); 4538 4539 trace_btrfs_truncate_show_fi_inline( 4540 BTRFS_I(inode), leaf, fi, path->slots[0], 4541 found_key.offset); 4542 } 4543 item_end--; 4544 } 4545 if (found_type > min_type) { 4546 del_item = 1; 4547 } else { 4548 if (item_end < new_size) 4549 break; 4550 if (found_key.offset >= new_size) 4551 del_item = 1; 4552 else 4553 del_item = 0; 4554 } 4555 found_extent = 0; 4556 /* FIXME, shrink the extent if the ref count is only 1 */ 4557 if (found_type != BTRFS_EXTENT_DATA_KEY) 4558 goto delete; 4559 4560 if (del_item) 4561 last_size = found_key.offset; 4562 else 4563 last_size = new_size; 4564 4565 if (extent_type != BTRFS_FILE_EXTENT_INLINE) { 4566 u64 num_dec; 4567 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi); 4568 if (!del_item) { 4569 u64 orig_num_bytes = 4570 btrfs_file_extent_num_bytes(leaf, fi); 4571 extent_num_bytes = ALIGN(new_size - 4572 found_key.offset, 4573 fs_info->sectorsize); 4574 btrfs_set_file_extent_num_bytes(leaf, fi, 4575 extent_num_bytes); 4576 num_dec = (orig_num_bytes - 4577 extent_num_bytes); 4578 if (test_bit(BTRFS_ROOT_REF_COWS, 4579 &root->state) && 4580 extent_start != 0) 4581 inode_sub_bytes(inode, num_dec); 4582 btrfs_mark_buffer_dirty(leaf); 4583 } else { 4584 extent_num_bytes = 4585 btrfs_file_extent_disk_num_bytes(leaf, 4586 fi); 4587 extent_offset = found_key.offset - 4588 btrfs_file_extent_offset(leaf, fi); 4589 4590 /* FIXME blocksize != 4096 */ 4591 num_dec = btrfs_file_extent_num_bytes(leaf, fi); 4592 if (extent_start != 0) { 4593 found_extent = 1; 4594 if (test_bit(BTRFS_ROOT_REF_COWS, 4595 &root->state)) 4596 inode_sub_bytes(inode, num_dec); 4597 } 4598 } 4599 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 4600 /* 4601 * we can't truncate inline items that have had 4602 * special encodings 4603 */ 4604 if (!del_item && 4605 btrfs_file_extent_encryption(leaf, fi) == 0 && 4606 btrfs_file_extent_other_encoding(leaf, fi) == 0) { 4607 4608 /* 4609 * Need to release path in order to truncate a 4610 * compressed extent. So delete any accumulated 4611 * extent items so far. 4612 */ 4613 if (btrfs_file_extent_compression(leaf, fi) != 4614 BTRFS_COMPRESS_NONE && pending_del_nr) { 4615 err = btrfs_del_items(trans, root, path, 4616 pending_del_slot, 4617 pending_del_nr); 4618 if (err) { 4619 btrfs_abort_transaction(trans, 4620 err); 4621 goto error; 4622 } 4623 pending_del_nr = 0; 4624 } 4625 4626 err = truncate_inline_extent(inode, path, 4627 &found_key, 4628 item_end, 4629 new_size); 4630 if (err) { 4631 btrfs_abort_transaction(trans, err); 4632 goto error; 4633 } 4634 } else if (test_bit(BTRFS_ROOT_REF_COWS, 4635 &root->state)) { 4636 inode_sub_bytes(inode, item_end + 1 - new_size); 4637 } 4638 } 4639 delete: 4640 if (del_item) { 4641 if (!pending_del_nr) { 4642 /* no pending yet, add ourselves */ 4643 pending_del_slot = path->slots[0]; 4644 pending_del_nr = 1; 4645 } else if (pending_del_nr && 4646 path->slots[0] + 1 == pending_del_slot) { 4647 /* hop on the pending chunk */ 4648 pending_del_nr++; 4649 pending_del_slot = path->slots[0]; 4650 } else { 4651 BUG(); 4652 } 4653 } else { 4654 break; 4655 } 4656 should_throttle = 0; 4657 4658 if (found_extent && 4659 (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || 4660 root == fs_info->tree_root)) { 4661 btrfs_set_path_blocking(path); 4662 bytes_deleted += extent_num_bytes; 4663 ret = btrfs_free_extent(trans, fs_info, extent_start, 4664 extent_num_bytes, 0, 4665 btrfs_header_owner(leaf), 4666 ino, extent_offset); 4667 BUG_ON(ret); 4668 if (btrfs_should_throttle_delayed_refs(trans, fs_info)) 4669 btrfs_async_run_delayed_refs(fs_info, 4670 trans->delayed_ref_updates * 2, 4671 trans->transid, 0); 4672 if (be_nice) { 4673 if (truncate_space_check(trans, root, 4674 extent_num_bytes)) { 4675 should_end = 1; 4676 } 4677 if (btrfs_should_throttle_delayed_refs(trans, 4678 fs_info)) 4679 should_throttle = 1; 4680 } 4681 } 4682 4683 if (found_type == BTRFS_INODE_ITEM_KEY) 4684 break; 4685 4686 if (path->slots[0] == 0 || 4687 path->slots[0] != pending_del_slot || 4688 should_throttle || should_end) { 4689 if (pending_del_nr) { 4690 ret = btrfs_del_items(trans, root, path, 4691 pending_del_slot, 4692 pending_del_nr); 4693 if (ret) { 4694 btrfs_abort_transaction(trans, ret); 4695 goto error; 4696 } 4697 pending_del_nr = 0; 4698 } 4699 btrfs_release_path(path); 4700 if (should_throttle) { 4701 unsigned long updates = trans->delayed_ref_updates; 4702 if (updates) { 4703 trans->delayed_ref_updates = 0; 4704 ret = btrfs_run_delayed_refs(trans, 4705 fs_info, 4706 updates * 2); 4707 if (ret && !err) 4708 err = ret; 4709 } 4710 } 4711 /* 4712 * if we failed to refill our space rsv, bail out 4713 * and let the transaction restart 4714 */ 4715 if (should_end) { 4716 err = -EAGAIN; 4717 goto error; 4718 } 4719 goto search_again; 4720 } else { 4721 path->slots[0]--; 4722 } 4723 } 4724 out: 4725 if (pending_del_nr) { 4726 ret = btrfs_del_items(trans, root, path, pending_del_slot, 4727 pending_del_nr); 4728 if (ret) 4729 btrfs_abort_transaction(trans, ret); 4730 } 4731 error: 4732 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { 4733 ASSERT(last_size >= new_size); 4734 if (!err && last_size > new_size) 4735 last_size = new_size; 4736 btrfs_ordered_update_i_size(inode, last_size, NULL); 4737 } 4738 4739 btrfs_free_path(path); 4740 4741 if (be_nice && bytes_deleted > SZ_32M) { 4742 unsigned long updates = trans->delayed_ref_updates; 4743 if (updates) { 4744 trans->delayed_ref_updates = 0; 4745 ret = btrfs_run_delayed_refs(trans, fs_info, 4746 updates * 2); 4747 if (ret && !err) 4748 err = ret; 4749 } 4750 } 4751 return err; 4752 } 4753 4754 /* 4755 * btrfs_truncate_block - read, zero a chunk and write a block 4756 * @inode - inode that we're zeroing 4757 * @from - the offset to start zeroing 4758 * @len - the length to zero, 0 to zero the entire range respective to the 4759 * offset 4760 * @front - zero up to the offset instead of from the offset on 4761 * 4762 * This will find the block for the "from" offset and cow the block and zero the 4763 * part we want to zero. This is used with truncate and hole punching. 4764 */ 4765 int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len, 4766 int front) 4767 { 4768 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 4769 struct address_space *mapping = inode->i_mapping; 4770 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 4771 struct btrfs_ordered_extent *ordered; 4772 struct extent_state *cached_state = NULL; 4773 struct extent_changeset *data_reserved = NULL; 4774 char *kaddr; 4775 u32 blocksize = fs_info->sectorsize; 4776 pgoff_t index = from >> PAGE_SHIFT; 4777 unsigned offset = from & (blocksize - 1); 4778 struct page *page; 4779 gfp_t mask = btrfs_alloc_write_mask(mapping); 4780 int ret = 0; 4781 u64 block_start; 4782 u64 block_end; 4783 4784 if ((offset & (blocksize - 1)) == 0 && 4785 (!len || ((len & (blocksize - 1)) == 0))) 4786 goto out; 4787 4788 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, 4789 round_down(from, blocksize), blocksize); 4790 if (ret) 4791 goto out; 4792 4793 again: 4794 page = find_or_create_page(mapping, index, mask); 4795 if (!page) { 4796 btrfs_delalloc_release_space(inode, data_reserved, 4797 round_down(from, blocksize), 4798 blocksize); 4799 ret = -ENOMEM; 4800 goto out; 4801 } 4802 4803 block_start = round_down(from, blocksize); 4804 block_end = block_start + blocksize - 1; 4805 4806 if (!PageUptodate(page)) { 4807 ret = btrfs_readpage(NULL, page); 4808 lock_page(page); 4809 if (page->mapping != mapping) { 4810 unlock_page(page); 4811 put_page(page); 4812 goto again; 4813 } 4814 if (!PageUptodate(page)) { 4815 ret = -EIO; 4816 goto out_unlock; 4817 } 4818 } 4819 wait_on_page_writeback(page); 4820 4821 lock_extent_bits(io_tree, block_start, block_end, &cached_state); 4822 set_page_extent_mapped(page); 4823 4824 ordered = btrfs_lookup_ordered_extent(inode, block_start); 4825 if (ordered) { 4826 unlock_extent_cached(io_tree, block_start, block_end, 4827 &cached_state, GFP_NOFS); 4828 unlock_page(page); 4829 put_page(page); 4830 btrfs_start_ordered_extent(inode, ordered, 1); 4831 btrfs_put_ordered_extent(ordered); 4832 goto again; 4833 } 4834 4835 clear_extent_bit(&BTRFS_I(inode)->io_tree, block_start, block_end, 4836 EXTENT_DIRTY | EXTENT_DELALLOC | 4837 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 4838 0, 0, &cached_state, GFP_NOFS); 4839 4840 ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 4841 &cached_state, 0); 4842 if (ret) { 4843 unlock_extent_cached(io_tree, block_start, block_end, 4844 &cached_state, GFP_NOFS); 4845 goto out_unlock; 4846 } 4847 4848 if (offset != blocksize) { 4849 if (!len) 4850 len = blocksize - offset; 4851 kaddr = kmap(page); 4852 if (front) 4853 memset(kaddr + (block_start - page_offset(page)), 4854 0, offset); 4855 else 4856 memset(kaddr + (block_start - page_offset(page)) + offset, 4857 0, len); 4858 flush_dcache_page(page); 4859 kunmap(page); 4860 } 4861 ClearPageChecked(page); 4862 set_page_dirty(page); 4863 unlock_extent_cached(io_tree, block_start, block_end, &cached_state, 4864 GFP_NOFS); 4865 4866 out_unlock: 4867 if (ret) 4868 btrfs_delalloc_release_space(inode, data_reserved, block_start, 4869 blocksize); 4870 unlock_page(page); 4871 put_page(page); 4872 out: 4873 extent_changeset_free(data_reserved); 4874 return ret; 4875 } 4876 4877 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode, 4878 u64 offset, u64 len) 4879 { 4880 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 4881 struct btrfs_trans_handle *trans; 4882 int ret; 4883 4884 /* 4885 * Still need to make sure the inode looks like it's been updated so 4886 * that any holes get logged if we fsync. 4887 */ 4888 if (btrfs_fs_incompat(fs_info, NO_HOLES)) { 4889 BTRFS_I(inode)->last_trans = fs_info->generation; 4890 BTRFS_I(inode)->last_sub_trans = root->log_transid; 4891 BTRFS_I(inode)->last_log_commit = root->last_log_commit; 4892 return 0; 4893 } 4894 4895 /* 4896 * 1 - for the one we're dropping 4897 * 1 - for the one we're adding 4898 * 1 - for updating the inode. 4899 */ 4900 trans = btrfs_start_transaction(root, 3); 4901 if (IS_ERR(trans)) 4902 return PTR_ERR(trans); 4903 4904 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1); 4905 if (ret) { 4906 btrfs_abort_transaction(trans, ret); 4907 btrfs_end_transaction(trans); 4908 return ret; 4909 } 4910 4911 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(BTRFS_I(inode)), 4912 offset, 0, 0, len, 0, len, 0, 0, 0); 4913 if (ret) 4914 btrfs_abort_transaction(trans, ret); 4915 else 4916 btrfs_update_inode(trans, root, inode); 4917 btrfs_end_transaction(trans); 4918 return ret; 4919 } 4920 4921 /* 4922 * This function puts in dummy file extents for the area we're creating a hole 4923 * for. So if we are truncating this file to a larger size we need to insert 4924 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for 4925 * the range between oldsize and size 4926 */ 4927 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size) 4928 { 4929 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 4930 struct btrfs_root *root = BTRFS_I(inode)->root; 4931 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 4932 struct extent_map *em = NULL; 4933 struct extent_state *cached_state = NULL; 4934 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 4935 u64 hole_start = ALIGN(oldsize, fs_info->sectorsize); 4936 u64 block_end = ALIGN(size, fs_info->sectorsize); 4937 u64 last_byte; 4938 u64 cur_offset; 4939 u64 hole_size; 4940 int err = 0; 4941 4942 /* 4943 * If our size started in the middle of a block we need to zero out the 4944 * rest of the block before we expand the i_size, otherwise we could 4945 * expose stale data. 4946 */ 4947 err = btrfs_truncate_block(inode, oldsize, 0, 0); 4948 if (err) 4949 return err; 4950 4951 if (size <= hole_start) 4952 return 0; 4953 4954 while (1) { 4955 struct btrfs_ordered_extent *ordered; 4956 4957 lock_extent_bits(io_tree, hole_start, block_end - 1, 4958 &cached_state); 4959 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), hole_start, 4960 block_end - hole_start); 4961 if (!ordered) 4962 break; 4963 unlock_extent_cached(io_tree, hole_start, block_end - 1, 4964 &cached_state, GFP_NOFS); 4965 btrfs_start_ordered_extent(inode, ordered, 1); 4966 btrfs_put_ordered_extent(ordered); 4967 } 4968 4969 cur_offset = hole_start; 4970 while (1) { 4971 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset, 4972 block_end - cur_offset, 0); 4973 if (IS_ERR(em)) { 4974 err = PTR_ERR(em); 4975 em = NULL; 4976 break; 4977 } 4978 last_byte = min(extent_map_end(em), block_end); 4979 last_byte = ALIGN(last_byte, fs_info->sectorsize); 4980 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) { 4981 struct extent_map *hole_em; 4982 hole_size = last_byte - cur_offset; 4983 4984 err = maybe_insert_hole(root, inode, cur_offset, 4985 hole_size); 4986 if (err) 4987 break; 4988 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, 4989 cur_offset + hole_size - 1, 0); 4990 hole_em = alloc_extent_map(); 4991 if (!hole_em) { 4992 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 4993 &BTRFS_I(inode)->runtime_flags); 4994 goto next; 4995 } 4996 hole_em->start = cur_offset; 4997 hole_em->len = hole_size; 4998 hole_em->orig_start = cur_offset; 4999 5000 hole_em->block_start = EXTENT_MAP_HOLE; 5001 hole_em->block_len = 0; 5002 hole_em->orig_block_len = 0; 5003 hole_em->ram_bytes = hole_size; 5004 hole_em->bdev = fs_info->fs_devices->latest_bdev; 5005 hole_em->compress_type = BTRFS_COMPRESS_NONE; 5006 hole_em->generation = fs_info->generation; 5007 5008 while (1) { 5009 write_lock(&em_tree->lock); 5010 err = add_extent_mapping(em_tree, hole_em, 1); 5011 write_unlock(&em_tree->lock); 5012 if (err != -EEXIST) 5013 break; 5014 btrfs_drop_extent_cache(BTRFS_I(inode), 5015 cur_offset, 5016 cur_offset + 5017 hole_size - 1, 0); 5018 } 5019 free_extent_map(hole_em); 5020 } 5021 next: 5022 free_extent_map(em); 5023 em = NULL; 5024 cur_offset = last_byte; 5025 if (cur_offset >= block_end) 5026 break; 5027 } 5028 free_extent_map(em); 5029 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state, 5030 GFP_NOFS); 5031 return err; 5032 } 5033 5034 static int btrfs_setsize(struct inode *inode, struct iattr *attr) 5035 { 5036 struct btrfs_root *root = BTRFS_I(inode)->root; 5037 struct btrfs_trans_handle *trans; 5038 loff_t oldsize = i_size_read(inode); 5039 loff_t newsize = attr->ia_size; 5040 int mask = attr->ia_valid; 5041 int ret; 5042 5043 /* 5044 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a 5045 * special case where we need to update the times despite not having 5046 * these flags set. For all other operations the VFS set these flags 5047 * explicitly if it wants a timestamp update. 5048 */ 5049 if (newsize != oldsize) { 5050 inode_inc_iversion(inode); 5051 if (!(mask & (ATTR_CTIME | ATTR_MTIME))) 5052 inode->i_ctime = inode->i_mtime = 5053 current_time(inode); 5054 } 5055 5056 if (newsize > oldsize) { 5057 /* 5058 * Don't do an expanding truncate while snapshoting is ongoing. 5059 * This is to ensure the snapshot captures a fully consistent 5060 * state of this file - if the snapshot captures this expanding 5061 * truncation, it must capture all writes that happened before 5062 * this truncation. 5063 */ 5064 btrfs_wait_for_snapshot_creation(root); 5065 ret = btrfs_cont_expand(inode, oldsize, newsize); 5066 if (ret) { 5067 btrfs_end_write_no_snapshoting(root); 5068 return ret; 5069 } 5070 5071 trans = btrfs_start_transaction(root, 1); 5072 if (IS_ERR(trans)) { 5073 btrfs_end_write_no_snapshoting(root); 5074 return PTR_ERR(trans); 5075 } 5076 5077 i_size_write(inode, newsize); 5078 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL); 5079 pagecache_isize_extended(inode, oldsize, newsize); 5080 ret = btrfs_update_inode(trans, root, inode); 5081 btrfs_end_write_no_snapshoting(root); 5082 btrfs_end_transaction(trans); 5083 } else { 5084 5085 /* 5086 * We're truncating a file that used to have good data down to 5087 * zero. Make sure it gets into the ordered flush list so that 5088 * any new writes get down to disk quickly. 5089 */ 5090 if (newsize == 0) 5091 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE, 5092 &BTRFS_I(inode)->runtime_flags); 5093 5094 /* 5095 * 1 for the orphan item we're going to add 5096 * 1 for the orphan item deletion. 5097 */ 5098 trans = btrfs_start_transaction(root, 2); 5099 if (IS_ERR(trans)) 5100 return PTR_ERR(trans); 5101 5102 /* 5103 * We need to do this in case we fail at _any_ point during the 5104 * actual truncate. Once we do the truncate_setsize we could 5105 * invalidate pages which forces any outstanding ordered io to 5106 * be instantly completed which will give us extents that need 5107 * to be truncated. If we fail to get an orphan inode down we 5108 * could have left over extents that were never meant to live, 5109 * so we need to guarantee from this point on that everything 5110 * will be consistent. 5111 */ 5112 ret = btrfs_orphan_add(trans, BTRFS_I(inode)); 5113 btrfs_end_transaction(trans); 5114 if (ret) 5115 return ret; 5116 5117 /* we don't support swapfiles, so vmtruncate shouldn't fail */ 5118 truncate_setsize(inode, newsize); 5119 5120 /* Disable nonlocked read DIO to avoid the end less truncate */ 5121 btrfs_inode_block_unlocked_dio(BTRFS_I(inode)); 5122 inode_dio_wait(inode); 5123 btrfs_inode_resume_unlocked_dio(BTRFS_I(inode)); 5124 5125 ret = btrfs_truncate(inode); 5126 if (ret && inode->i_nlink) { 5127 int err; 5128 5129 /* To get a stable disk_i_size */ 5130 err = btrfs_wait_ordered_range(inode, 0, (u64)-1); 5131 if (err) { 5132 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5133 return err; 5134 } 5135 5136 /* 5137 * failed to truncate, disk_i_size is only adjusted down 5138 * as we remove extents, so it should represent the true 5139 * size of the inode, so reset the in memory size and 5140 * delete our orphan entry. 5141 */ 5142 trans = btrfs_join_transaction(root); 5143 if (IS_ERR(trans)) { 5144 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5145 return ret; 5146 } 5147 i_size_write(inode, BTRFS_I(inode)->disk_i_size); 5148 err = btrfs_orphan_del(trans, BTRFS_I(inode)); 5149 if (err) 5150 btrfs_abort_transaction(trans, err); 5151 btrfs_end_transaction(trans); 5152 } 5153 } 5154 5155 return ret; 5156 } 5157 5158 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) 5159 { 5160 struct inode *inode = d_inode(dentry); 5161 struct btrfs_root *root = BTRFS_I(inode)->root; 5162 int err; 5163 5164 if (btrfs_root_readonly(root)) 5165 return -EROFS; 5166 5167 err = setattr_prepare(dentry, attr); 5168 if (err) 5169 return err; 5170 5171 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { 5172 err = btrfs_setsize(inode, attr); 5173 if (err) 5174 return err; 5175 } 5176 5177 if (attr->ia_valid) { 5178 setattr_copy(inode, attr); 5179 inode_inc_iversion(inode); 5180 err = btrfs_dirty_inode(inode); 5181 5182 if (!err && attr->ia_valid & ATTR_MODE) 5183 err = posix_acl_chmod(inode, inode->i_mode); 5184 } 5185 5186 return err; 5187 } 5188 5189 /* 5190 * While truncating the inode pages during eviction, we get the VFS calling 5191 * btrfs_invalidatepage() against each page of the inode. This is slow because 5192 * the calls to btrfs_invalidatepage() result in a huge amount of calls to 5193 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting 5194 * extent_state structures over and over, wasting lots of time. 5195 * 5196 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all 5197 * those expensive operations on a per page basis and do only the ordered io 5198 * finishing, while we release here the extent_map and extent_state structures, 5199 * without the excessive merging and splitting. 5200 */ 5201 static void evict_inode_truncate_pages(struct inode *inode) 5202 { 5203 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 5204 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree; 5205 struct rb_node *node; 5206 5207 ASSERT(inode->i_state & I_FREEING); 5208 truncate_inode_pages_final(&inode->i_data); 5209 5210 write_lock(&map_tree->lock); 5211 while (!RB_EMPTY_ROOT(&map_tree->map)) { 5212 struct extent_map *em; 5213 5214 node = rb_first(&map_tree->map); 5215 em = rb_entry(node, struct extent_map, rb_node); 5216 clear_bit(EXTENT_FLAG_PINNED, &em->flags); 5217 clear_bit(EXTENT_FLAG_LOGGING, &em->flags); 5218 remove_extent_mapping(map_tree, em); 5219 free_extent_map(em); 5220 if (need_resched()) { 5221 write_unlock(&map_tree->lock); 5222 cond_resched(); 5223 write_lock(&map_tree->lock); 5224 } 5225 } 5226 write_unlock(&map_tree->lock); 5227 5228 /* 5229 * Keep looping until we have no more ranges in the io tree. 5230 * We can have ongoing bios started by readpages (called from readahead) 5231 * that have their endio callback (extent_io.c:end_bio_extent_readpage) 5232 * still in progress (unlocked the pages in the bio but did not yet 5233 * unlocked the ranges in the io tree). Therefore this means some 5234 * ranges can still be locked and eviction started because before 5235 * submitting those bios, which are executed by a separate task (work 5236 * queue kthread), inode references (inode->i_count) were not taken 5237 * (which would be dropped in the end io callback of each bio). 5238 * Therefore here we effectively end up waiting for those bios and 5239 * anyone else holding locked ranges without having bumped the inode's 5240 * reference count - if we don't do it, when they access the inode's 5241 * io_tree to unlock a range it may be too late, leading to an 5242 * use-after-free issue. 5243 */ 5244 spin_lock(&io_tree->lock); 5245 while (!RB_EMPTY_ROOT(&io_tree->state)) { 5246 struct extent_state *state; 5247 struct extent_state *cached_state = NULL; 5248 u64 start; 5249 u64 end; 5250 5251 node = rb_first(&io_tree->state); 5252 state = rb_entry(node, struct extent_state, rb_node); 5253 start = state->start; 5254 end = state->end; 5255 spin_unlock(&io_tree->lock); 5256 5257 lock_extent_bits(io_tree, start, end, &cached_state); 5258 5259 /* 5260 * If still has DELALLOC flag, the extent didn't reach disk, 5261 * and its reserved space won't be freed by delayed_ref. 5262 * So we need to free its reserved space here. 5263 * (Refer to comment in btrfs_invalidatepage, case 2) 5264 * 5265 * Note, end is the bytenr of last byte, so we need + 1 here. 5266 */ 5267 if (state->state & EXTENT_DELALLOC) 5268 btrfs_qgroup_free_data(inode, NULL, start, end - start + 1); 5269 5270 clear_extent_bit(io_tree, start, end, 5271 EXTENT_LOCKED | EXTENT_DIRTY | 5272 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | 5273 EXTENT_DEFRAG, 1, 1, 5274 &cached_state, GFP_NOFS); 5275 5276 cond_resched(); 5277 spin_lock(&io_tree->lock); 5278 } 5279 spin_unlock(&io_tree->lock); 5280 } 5281 5282 void btrfs_evict_inode(struct inode *inode) 5283 { 5284 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5285 struct btrfs_trans_handle *trans; 5286 struct btrfs_root *root = BTRFS_I(inode)->root; 5287 struct btrfs_block_rsv *rsv, *global_rsv; 5288 int steal_from_global = 0; 5289 u64 min_size; 5290 int ret; 5291 5292 trace_btrfs_inode_evict(inode); 5293 5294 if (!root) { 5295 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); 5296 return; 5297 } 5298 5299 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1); 5300 5301 evict_inode_truncate_pages(inode); 5302 5303 if (inode->i_nlink && 5304 ((btrfs_root_refs(&root->root_item) != 0 && 5305 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) || 5306 btrfs_is_free_space_inode(BTRFS_I(inode)))) 5307 goto no_delete; 5308 5309 if (is_bad_inode(inode)) { 5310 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5311 goto no_delete; 5312 } 5313 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */ 5314 if (!special_file(inode->i_mode)) 5315 btrfs_wait_ordered_range(inode, 0, (u64)-1); 5316 5317 btrfs_free_io_failure_record(BTRFS_I(inode), 0, (u64)-1); 5318 5319 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) { 5320 BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 5321 &BTRFS_I(inode)->runtime_flags)); 5322 goto no_delete; 5323 } 5324 5325 if (inode->i_nlink > 0) { 5326 BUG_ON(btrfs_root_refs(&root->root_item) != 0 && 5327 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID); 5328 goto no_delete; 5329 } 5330 5331 ret = btrfs_commit_inode_delayed_inode(BTRFS_I(inode)); 5332 if (ret) { 5333 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5334 goto no_delete; 5335 } 5336 5337 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); 5338 if (!rsv) { 5339 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5340 goto no_delete; 5341 } 5342 rsv->size = min_size; 5343 rsv->failfast = 1; 5344 global_rsv = &fs_info->global_block_rsv; 5345 5346 btrfs_i_size_write(BTRFS_I(inode), 0); 5347 5348 /* 5349 * This is a bit simpler than btrfs_truncate since we've already 5350 * reserved our space for our orphan item in the unlink, so we just 5351 * need to reserve some slack space in case we add bytes and update 5352 * inode item when doing the truncate. 5353 */ 5354 while (1) { 5355 ret = btrfs_block_rsv_refill(root, rsv, min_size, 5356 BTRFS_RESERVE_FLUSH_LIMIT); 5357 5358 /* 5359 * Try and steal from the global reserve since we will 5360 * likely not use this space anyway, we want to try as 5361 * hard as possible to get this to work. 5362 */ 5363 if (ret) 5364 steal_from_global++; 5365 else 5366 steal_from_global = 0; 5367 ret = 0; 5368 5369 /* 5370 * steal_from_global == 0: we reserved stuff, hooray! 5371 * steal_from_global == 1: we didn't reserve stuff, boo! 5372 * steal_from_global == 2: we've committed, still not a lot of 5373 * room but maybe we'll have room in the global reserve this 5374 * time. 5375 * steal_from_global == 3: abandon all hope! 5376 */ 5377 if (steal_from_global > 2) { 5378 btrfs_warn(fs_info, 5379 "Could not get space for a delete, will truncate on mount %d", 5380 ret); 5381 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5382 btrfs_free_block_rsv(fs_info, rsv); 5383 goto no_delete; 5384 } 5385 5386 trans = btrfs_join_transaction(root); 5387 if (IS_ERR(trans)) { 5388 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5389 btrfs_free_block_rsv(fs_info, rsv); 5390 goto no_delete; 5391 } 5392 5393 /* 5394 * We can't just steal from the global reserve, we need to make 5395 * sure there is room to do it, if not we need to commit and try 5396 * again. 5397 */ 5398 if (steal_from_global) { 5399 if (!btrfs_check_space_for_delayed_refs(trans, fs_info)) 5400 ret = btrfs_block_rsv_migrate(global_rsv, rsv, 5401 min_size, 0); 5402 else 5403 ret = -ENOSPC; 5404 } 5405 5406 /* 5407 * Couldn't steal from the global reserve, we have too much 5408 * pending stuff built up, commit the transaction and try it 5409 * again. 5410 */ 5411 if (ret) { 5412 ret = btrfs_commit_transaction(trans); 5413 if (ret) { 5414 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5415 btrfs_free_block_rsv(fs_info, rsv); 5416 goto no_delete; 5417 } 5418 continue; 5419 } else { 5420 steal_from_global = 0; 5421 } 5422 5423 trans->block_rsv = rsv; 5424 5425 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0); 5426 if (ret != -ENOSPC && ret != -EAGAIN) 5427 break; 5428 5429 trans->block_rsv = &fs_info->trans_block_rsv; 5430 btrfs_end_transaction(trans); 5431 trans = NULL; 5432 btrfs_btree_balance_dirty(fs_info); 5433 } 5434 5435 btrfs_free_block_rsv(fs_info, rsv); 5436 5437 /* 5438 * Errors here aren't a big deal, it just means we leave orphan items 5439 * in the tree. They will be cleaned up on the next mount. 5440 */ 5441 if (ret == 0) { 5442 trans->block_rsv = root->orphan_block_rsv; 5443 btrfs_orphan_del(trans, BTRFS_I(inode)); 5444 } else { 5445 btrfs_orphan_del(NULL, BTRFS_I(inode)); 5446 } 5447 5448 trans->block_rsv = &fs_info->trans_block_rsv; 5449 if (!(root == fs_info->tree_root || 5450 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)) 5451 btrfs_return_ino(root, btrfs_ino(BTRFS_I(inode))); 5452 5453 btrfs_end_transaction(trans); 5454 btrfs_btree_balance_dirty(fs_info); 5455 no_delete: 5456 btrfs_remove_delayed_node(BTRFS_I(inode)); 5457 clear_inode(inode); 5458 } 5459 5460 /* 5461 * this returns the key found in the dir entry in the location pointer. 5462 * If no dir entries were found, location->objectid is 0. 5463 */ 5464 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, 5465 struct btrfs_key *location) 5466 { 5467 const char *name = dentry->d_name.name; 5468 int namelen = dentry->d_name.len; 5469 struct btrfs_dir_item *di; 5470 struct btrfs_path *path; 5471 struct btrfs_root *root = BTRFS_I(dir)->root; 5472 int ret = 0; 5473 5474 path = btrfs_alloc_path(); 5475 if (!path) 5476 return -ENOMEM; 5477 5478 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(BTRFS_I(dir)), 5479 name, namelen, 0); 5480 if (IS_ERR(di)) 5481 ret = PTR_ERR(di); 5482 5483 if (IS_ERR_OR_NULL(di)) 5484 goto out_err; 5485 5486 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); 5487 out: 5488 btrfs_free_path(path); 5489 return ret; 5490 out_err: 5491 location->objectid = 0; 5492 goto out; 5493 } 5494 5495 /* 5496 * when we hit a tree root in a directory, the btrfs part of the inode 5497 * needs to be changed to reflect the root directory of the tree root. This 5498 * is kind of like crossing a mount point. 5499 */ 5500 static int fixup_tree_root_location(struct btrfs_fs_info *fs_info, 5501 struct inode *dir, 5502 struct dentry *dentry, 5503 struct btrfs_key *location, 5504 struct btrfs_root **sub_root) 5505 { 5506 struct btrfs_path *path; 5507 struct btrfs_root *new_root; 5508 struct btrfs_root_ref *ref; 5509 struct extent_buffer *leaf; 5510 struct btrfs_key key; 5511 int ret; 5512 int err = 0; 5513 5514 path = btrfs_alloc_path(); 5515 if (!path) { 5516 err = -ENOMEM; 5517 goto out; 5518 } 5519 5520 err = -ENOENT; 5521 key.objectid = BTRFS_I(dir)->root->root_key.objectid; 5522 key.type = BTRFS_ROOT_REF_KEY; 5523 key.offset = location->objectid; 5524 5525 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 5526 if (ret) { 5527 if (ret < 0) 5528 err = ret; 5529 goto out; 5530 } 5531 5532 leaf = path->nodes[0]; 5533 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); 5534 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(BTRFS_I(dir)) || 5535 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len) 5536 goto out; 5537 5538 ret = memcmp_extent_buffer(leaf, dentry->d_name.name, 5539 (unsigned long)(ref + 1), 5540 dentry->d_name.len); 5541 if (ret) 5542 goto out; 5543 5544 btrfs_release_path(path); 5545 5546 new_root = btrfs_read_fs_root_no_name(fs_info, location); 5547 if (IS_ERR(new_root)) { 5548 err = PTR_ERR(new_root); 5549 goto out; 5550 } 5551 5552 *sub_root = new_root; 5553 location->objectid = btrfs_root_dirid(&new_root->root_item); 5554 location->type = BTRFS_INODE_ITEM_KEY; 5555 location->offset = 0; 5556 err = 0; 5557 out: 5558 btrfs_free_path(path); 5559 return err; 5560 } 5561 5562 static void inode_tree_add(struct inode *inode) 5563 { 5564 struct btrfs_root *root = BTRFS_I(inode)->root; 5565 struct btrfs_inode *entry; 5566 struct rb_node **p; 5567 struct rb_node *parent; 5568 struct rb_node *new = &BTRFS_I(inode)->rb_node; 5569 u64 ino = btrfs_ino(BTRFS_I(inode)); 5570 5571 if (inode_unhashed(inode)) 5572 return; 5573 parent = NULL; 5574 spin_lock(&root->inode_lock); 5575 p = &root->inode_tree.rb_node; 5576 while (*p) { 5577 parent = *p; 5578 entry = rb_entry(parent, struct btrfs_inode, rb_node); 5579 5580 if (ino < btrfs_ino(BTRFS_I(&entry->vfs_inode))) 5581 p = &parent->rb_left; 5582 else if (ino > btrfs_ino(BTRFS_I(&entry->vfs_inode))) 5583 p = &parent->rb_right; 5584 else { 5585 WARN_ON(!(entry->vfs_inode.i_state & 5586 (I_WILL_FREE | I_FREEING))); 5587 rb_replace_node(parent, new, &root->inode_tree); 5588 RB_CLEAR_NODE(parent); 5589 spin_unlock(&root->inode_lock); 5590 return; 5591 } 5592 } 5593 rb_link_node(new, parent, p); 5594 rb_insert_color(new, &root->inode_tree); 5595 spin_unlock(&root->inode_lock); 5596 } 5597 5598 static void inode_tree_del(struct inode *inode) 5599 { 5600 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5601 struct btrfs_root *root = BTRFS_I(inode)->root; 5602 int empty = 0; 5603 5604 spin_lock(&root->inode_lock); 5605 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { 5606 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); 5607 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); 5608 empty = RB_EMPTY_ROOT(&root->inode_tree); 5609 } 5610 spin_unlock(&root->inode_lock); 5611 5612 if (empty && btrfs_root_refs(&root->root_item) == 0) { 5613 synchronize_srcu(&fs_info->subvol_srcu); 5614 spin_lock(&root->inode_lock); 5615 empty = RB_EMPTY_ROOT(&root->inode_tree); 5616 spin_unlock(&root->inode_lock); 5617 if (empty) 5618 btrfs_add_dead_root(root); 5619 } 5620 } 5621 5622 void btrfs_invalidate_inodes(struct btrfs_root *root) 5623 { 5624 struct btrfs_fs_info *fs_info = root->fs_info; 5625 struct rb_node *node; 5626 struct rb_node *prev; 5627 struct btrfs_inode *entry; 5628 struct inode *inode; 5629 u64 objectid = 0; 5630 5631 if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 5632 WARN_ON(btrfs_root_refs(&root->root_item) != 0); 5633 5634 spin_lock(&root->inode_lock); 5635 again: 5636 node = root->inode_tree.rb_node; 5637 prev = NULL; 5638 while (node) { 5639 prev = node; 5640 entry = rb_entry(node, struct btrfs_inode, rb_node); 5641 5642 if (objectid < btrfs_ino(BTRFS_I(&entry->vfs_inode))) 5643 node = node->rb_left; 5644 else if (objectid > btrfs_ino(BTRFS_I(&entry->vfs_inode))) 5645 node = node->rb_right; 5646 else 5647 break; 5648 } 5649 if (!node) { 5650 while (prev) { 5651 entry = rb_entry(prev, struct btrfs_inode, rb_node); 5652 if (objectid <= btrfs_ino(BTRFS_I(&entry->vfs_inode))) { 5653 node = prev; 5654 break; 5655 } 5656 prev = rb_next(prev); 5657 } 5658 } 5659 while (node) { 5660 entry = rb_entry(node, struct btrfs_inode, rb_node); 5661 objectid = btrfs_ino(BTRFS_I(&entry->vfs_inode)) + 1; 5662 inode = igrab(&entry->vfs_inode); 5663 if (inode) { 5664 spin_unlock(&root->inode_lock); 5665 if (atomic_read(&inode->i_count) > 1) 5666 d_prune_aliases(inode); 5667 /* 5668 * btrfs_drop_inode will have it removed from 5669 * the inode cache when its usage count 5670 * hits zero. 5671 */ 5672 iput(inode); 5673 cond_resched(); 5674 spin_lock(&root->inode_lock); 5675 goto again; 5676 } 5677 5678 if (cond_resched_lock(&root->inode_lock)) 5679 goto again; 5680 5681 node = rb_next(node); 5682 } 5683 spin_unlock(&root->inode_lock); 5684 } 5685 5686 static int btrfs_init_locked_inode(struct inode *inode, void *p) 5687 { 5688 struct btrfs_iget_args *args = p; 5689 inode->i_ino = args->location->objectid; 5690 memcpy(&BTRFS_I(inode)->location, args->location, 5691 sizeof(*args->location)); 5692 BTRFS_I(inode)->root = args->root; 5693 return 0; 5694 } 5695 5696 static int btrfs_find_actor(struct inode *inode, void *opaque) 5697 { 5698 struct btrfs_iget_args *args = opaque; 5699 return args->location->objectid == BTRFS_I(inode)->location.objectid && 5700 args->root == BTRFS_I(inode)->root; 5701 } 5702 5703 static struct inode *btrfs_iget_locked(struct super_block *s, 5704 struct btrfs_key *location, 5705 struct btrfs_root *root) 5706 { 5707 struct inode *inode; 5708 struct btrfs_iget_args args; 5709 unsigned long hashval = btrfs_inode_hash(location->objectid, root); 5710 5711 args.location = location; 5712 args.root = root; 5713 5714 inode = iget5_locked(s, hashval, btrfs_find_actor, 5715 btrfs_init_locked_inode, 5716 (void *)&args); 5717 return inode; 5718 } 5719 5720 /* Get an inode object given its location and corresponding root. 5721 * Returns in *is_new if the inode was read from disk 5722 */ 5723 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, 5724 struct btrfs_root *root, int *new) 5725 { 5726 struct inode *inode; 5727 5728 inode = btrfs_iget_locked(s, location, root); 5729 if (!inode) 5730 return ERR_PTR(-ENOMEM); 5731 5732 if (inode->i_state & I_NEW) { 5733 int ret; 5734 5735 ret = btrfs_read_locked_inode(inode); 5736 if (!is_bad_inode(inode)) { 5737 inode_tree_add(inode); 5738 unlock_new_inode(inode); 5739 if (new) 5740 *new = 1; 5741 } else { 5742 unlock_new_inode(inode); 5743 iput(inode); 5744 ASSERT(ret < 0); 5745 inode = ERR_PTR(ret < 0 ? ret : -ESTALE); 5746 } 5747 } 5748 5749 return inode; 5750 } 5751 5752 static struct inode *new_simple_dir(struct super_block *s, 5753 struct btrfs_key *key, 5754 struct btrfs_root *root) 5755 { 5756 struct inode *inode = new_inode(s); 5757 5758 if (!inode) 5759 return ERR_PTR(-ENOMEM); 5760 5761 BTRFS_I(inode)->root = root; 5762 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key)); 5763 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags); 5764 5765 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID; 5766 inode->i_op = &btrfs_dir_ro_inode_operations; 5767 inode->i_opflags &= ~IOP_XATTR; 5768 inode->i_fop = &simple_dir_operations; 5769 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; 5770 inode->i_mtime = current_time(inode); 5771 inode->i_atime = inode->i_mtime; 5772 inode->i_ctime = inode->i_mtime; 5773 BTRFS_I(inode)->i_otime = inode->i_mtime; 5774 5775 return inode; 5776 } 5777 5778 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) 5779 { 5780 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 5781 struct inode *inode; 5782 struct btrfs_root *root = BTRFS_I(dir)->root; 5783 struct btrfs_root *sub_root = root; 5784 struct btrfs_key location; 5785 int index; 5786 int ret = 0; 5787 5788 if (dentry->d_name.len > BTRFS_NAME_LEN) 5789 return ERR_PTR(-ENAMETOOLONG); 5790 5791 ret = btrfs_inode_by_name(dir, dentry, &location); 5792 if (ret < 0) 5793 return ERR_PTR(ret); 5794 5795 if (location.objectid == 0) 5796 return ERR_PTR(-ENOENT); 5797 5798 if (location.type == BTRFS_INODE_ITEM_KEY) { 5799 inode = btrfs_iget(dir->i_sb, &location, root, NULL); 5800 return inode; 5801 } 5802 5803 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); 5804 5805 index = srcu_read_lock(&fs_info->subvol_srcu); 5806 ret = fixup_tree_root_location(fs_info, dir, dentry, 5807 &location, &sub_root); 5808 if (ret < 0) { 5809 if (ret != -ENOENT) 5810 inode = ERR_PTR(ret); 5811 else 5812 inode = new_simple_dir(dir->i_sb, &location, sub_root); 5813 } else { 5814 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL); 5815 } 5816 srcu_read_unlock(&fs_info->subvol_srcu, index); 5817 5818 if (!IS_ERR(inode) && root != sub_root) { 5819 down_read(&fs_info->cleanup_work_sem); 5820 if (!(inode->i_sb->s_flags & MS_RDONLY)) 5821 ret = btrfs_orphan_cleanup(sub_root); 5822 up_read(&fs_info->cleanup_work_sem); 5823 if (ret) { 5824 iput(inode); 5825 inode = ERR_PTR(ret); 5826 } 5827 } 5828 5829 return inode; 5830 } 5831 5832 static int btrfs_dentry_delete(const struct dentry *dentry) 5833 { 5834 struct btrfs_root *root; 5835 struct inode *inode = d_inode(dentry); 5836 5837 if (!inode && !IS_ROOT(dentry)) 5838 inode = d_inode(dentry->d_parent); 5839 5840 if (inode) { 5841 root = BTRFS_I(inode)->root; 5842 if (btrfs_root_refs(&root->root_item) == 0) 5843 return 1; 5844 5845 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) 5846 return 1; 5847 } 5848 return 0; 5849 } 5850 5851 static void btrfs_dentry_release(struct dentry *dentry) 5852 { 5853 kfree(dentry->d_fsdata); 5854 } 5855 5856 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, 5857 unsigned int flags) 5858 { 5859 struct inode *inode; 5860 5861 inode = btrfs_lookup_dentry(dir, dentry); 5862 if (IS_ERR(inode)) { 5863 if (PTR_ERR(inode) == -ENOENT) 5864 inode = NULL; 5865 else 5866 return ERR_CAST(inode); 5867 } 5868 5869 return d_splice_alias(inode, dentry); 5870 } 5871 5872 unsigned char btrfs_filetype_table[] = { 5873 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK 5874 }; 5875 5876 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx) 5877 { 5878 struct inode *inode = file_inode(file); 5879 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5880 struct btrfs_root *root = BTRFS_I(inode)->root; 5881 struct btrfs_dir_item *di; 5882 struct btrfs_key key; 5883 struct btrfs_key found_key; 5884 struct btrfs_path *path; 5885 struct list_head ins_list; 5886 struct list_head del_list; 5887 int ret; 5888 struct extent_buffer *leaf; 5889 int slot; 5890 unsigned char d_type; 5891 int over = 0; 5892 char tmp_name[32]; 5893 char *name_ptr; 5894 int name_len; 5895 bool put = false; 5896 struct btrfs_key location; 5897 5898 if (!dir_emit_dots(file, ctx)) 5899 return 0; 5900 5901 path = btrfs_alloc_path(); 5902 if (!path) 5903 return -ENOMEM; 5904 5905 path->reada = READA_FORWARD; 5906 5907 INIT_LIST_HEAD(&ins_list); 5908 INIT_LIST_HEAD(&del_list); 5909 put = btrfs_readdir_get_delayed_items(inode, &ins_list, &del_list); 5910 5911 key.type = BTRFS_DIR_INDEX_KEY; 5912 key.offset = ctx->pos; 5913 key.objectid = btrfs_ino(BTRFS_I(inode)); 5914 5915 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5916 if (ret < 0) 5917 goto err; 5918 5919 while (1) { 5920 leaf = path->nodes[0]; 5921 slot = path->slots[0]; 5922 if (slot >= btrfs_header_nritems(leaf)) { 5923 ret = btrfs_next_leaf(root, path); 5924 if (ret < 0) 5925 goto err; 5926 else if (ret > 0) 5927 break; 5928 continue; 5929 } 5930 5931 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5932 5933 if (found_key.objectid != key.objectid) 5934 break; 5935 if (found_key.type != BTRFS_DIR_INDEX_KEY) 5936 break; 5937 if (found_key.offset < ctx->pos) 5938 goto next; 5939 if (btrfs_should_delete_dir_index(&del_list, found_key.offset)) 5940 goto next; 5941 5942 ctx->pos = found_key.offset; 5943 5944 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); 5945 if (verify_dir_item(fs_info, leaf, slot, di)) 5946 goto next; 5947 5948 name_len = btrfs_dir_name_len(leaf, di); 5949 if (name_len <= sizeof(tmp_name)) { 5950 name_ptr = tmp_name; 5951 } else { 5952 name_ptr = kmalloc(name_len, GFP_KERNEL); 5953 if (!name_ptr) { 5954 ret = -ENOMEM; 5955 goto err; 5956 } 5957 } 5958 read_extent_buffer(leaf, name_ptr, (unsigned long)(di + 1), 5959 name_len); 5960 5961 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)]; 5962 btrfs_dir_item_key_to_cpu(leaf, di, &location); 5963 5964 over = !dir_emit(ctx, name_ptr, name_len, location.objectid, 5965 d_type); 5966 5967 if (name_ptr != tmp_name) 5968 kfree(name_ptr); 5969 5970 if (over) 5971 goto nopos; 5972 ctx->pos++; 5973 next: 5974 path->slots[0]++; 5975 } 5976 5977 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list); 5978 if (ret) 5979 goto nopos; 5980 5981 /* 5982 * Stop new entries from being returned after we return the last 5983 * entry. 5984 * 5985 * New directory entries are assigned a strictly increasing 5986 * offset. This means that new entries created during readdir 5987 * are *guaranteed* to be seen in the future by that readdir. 5988 * This has broken buggy programs which operate on names as 5989 * they're returned by readdir. Until we re-use freed offsets 5990 * we have this hack to stop new entries from being returned 5991 * under the assumption that they'll never reach this huge 5992 * offset. 5993 * 5994 * This is being careful not to overflow 32bit loff_t unless the 5995 * last entry requires it because doing so has broken 32bit apps 5996 * in the past. 5997 */ 5998 if (ctx->pos >= INT_MAX) 5999 ctx->pos = LLONG_MAX; 6000 else 6001 ctx->pos = INT_MAX; 6002 nopos: 6003 ret = 0; 6004 err: 6005 if (put) 6006 btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list); 6007 btrfs_free_path(path); 6008 return ret; 6009 } 6010 6011 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc) 6012 { 6013 struct btrfs_root *root = BTRFS_I(inode)->root; 6014 struct btrfs_trans_handle *trans; 6015 int ret = 0; 6016 bool nolock = false; 6017 6018 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags)) 6019 return 0; 6020 6021 if (btrfs_fs_closing(root->fs_info) && 6022 btrfs_is_free_space_inode(BTRFS_I(inode))) 6023 nolock = true; 6024 6025 if (wbc->sync_mode == WB_SYNC_ALL) { 6026 if (nolock) 6027 trans = btrfs_join_transaction_nolock(root); 6028 else 6029 trans = btrfs_join_transaction(root); 6030 if (IS_ERR(trans)) 6031 return PTR_ERR(trans); 6032 ret = btrfs_commit_transaction(trans); 6033 } 6034 return ret; 6035 } 6036 6037 /* 6038 * This is somewhat expensive, updating the tree every time the 6039 * inode changes. But, it is most likely to find the inode in cache. 6040 * FIXME, needs more benchmarking...there are no reasons other than performance 6041 * to keep or drop this code. 6042 */ 6043 static int btrfs_dirty_inode(struct inode *inode) 6044 { 6045 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 6046 struct btrfs_root *root = BTRFS_I(inode)->root; 6047 struct btrfs_trans_handle *trans; 6048 int ret; 6049 6050 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags)) 6051 return 0; 6052 6053 trans = btrfs_join_transaction(root); 6054 if (IS_ERR(trans)) 6055 return PTR_ERR(trans); 6056 6057 ret = btrfs_update_inode(trans, root, inode); 6058 if (ret && ret == -ENOSPC) { 6059 /* whoops, lets try again with the full transaction */ 6060 btrfs_end_transaction(trans); 6061 trans = btrfs_start_transaction(root, 1); 6062 if (IS_ERR(trans)) 6063 return PTR_ERR(trans); 6064 6065 ret = btrfs_update_inode(trans, root, inode); 6066 } 6067 btrfs_end_transaction(trans); 6068 if (BTRFS_I(inode)->delayed_node) 6069 btrfs_balance_delayed_items(fs_info); 6070 6071 return ret; 6072 } 6073 6074 /* 6075 * This is a copy of file_update_time. We need this so we can return error on 6076 * ENOSPC for updating the inode in the case of file write and mmap writes. 6077 */ 6078 static int btrfs_update_time(struct inode *inode, struct timespec *now, 6079 int flags) 6080 { 6081 struct btrfs_root *root = BTRFS_I(inode)->root; 6082 6083 if (btrfs_root_readonly(root)) 6084 return -EROFS; 6085 6086 if (flags & S_VERSION) 6087 inode_inc_iversion(inode); 6088 if (flags & S_CTIME) 6089 inode->i_ctime = *now; 6090 if (flags & S_MTIME) 6091 inode->i_mtime = *now; 6092 if (flags & S_ATIME) 6093 inode->i_atime = *now; 6094 return btrfs_dirty_inode(inode); 6095 } 6096 6097 /* 6098 * find the highest existing sequence number in a directory 6099 * and then set the in-memory index_cnt variable to reflect 6100 * free sequence numbers 6101 */ 6102 static int btrfs_set_inode_index_count(struct btrfs_inode *inode) 6103 { 6104 struct btrfs_root *root = inode->root; 6105 struct btrfs_key key, found_key; 6106 struct btrfs_path *path; 6107 struct extent_buffer *leaf; 6108 int ret; 6109 6110 key.objectid = btrfs_ino(inode); 6111 key.type = BTRFS_DIR_INDEX_KEY; 6112 key.offset = (u64)-1; 6113 6114 path = btrfs_alloc_path(); 6115 if (!path) 6116 return -ENOMEM; 6117 6118 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 6119 if (ret < 0) 6120 goto out; 6121 /* FIXME: we should be able to handle this */ 6122 if (ret == 0) 6123 goto out; 6124 ret = 0; 6125 6126 /* 6127 * MAGIC NUMBER EXPLANATION: 6128 * since we search a directory based on f_pos we have to start at 2 6129 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody 6130 * else has to start at 2 6131 */ 6132 if (path->slots[0] == 0) { 6133 inode->index_cnt = 2; 6134 goto out; 6135 } 6136 6137 path->slots[0]--; 6138 6139 leaf = path->nodes[0]; 6140 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6141 6142 if (found_key.objectid != btrfs_ino(inode) || 6143 found_key.type != BTRFS_DIR_INDEX_KEY) { 6144 inode->index_cnt = 2; 6145 goto out; 6146 } 6147 6148 inode->index_cnt = found_key.offset + 1; 6149 out: 6150 btrfs_free_path(path); 6151 return ret; 6152 } 6153 6154 /* 6155 * helper to find a free sequence number in a given directory. This current 6156 * code is very simple, later versions will do smarter things in the btree 6157 */ 6158 int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index) 6159 { 6160 int ret = 0; 6161 6162 if (dir->index_cnt == (u64)-1) { 6163 ret = btrfs_inode_delayed_dir_index_count(dir); 6164 if (ret) { 6165 ret = btrfs_set_inode_index_count(dir); 6166 if (ret) 6167 return ret; 6168 } 6169 } 6170 6171 *index = dir->index_cnt; 6172 dir->index_cnt++; 6173 6174 return ret; 6175 } 6176 6177 static int btrfs_insert_inode_locked(struct inode *inode) 6178 { 6179 struct btrfs_iget_args args; 6180 args.location = &BTRFS_I(inode)->location; 6181 args.root = BTRFS_I(inode)->root; 6182 6183 return insert_inode_locked4(inode, 6184 btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root), 6185 btrfs_find_actor, &args); 6186 } 6187 6188 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, 6189 struct btrfs_root *root, 6190 struct inode *dir, 6191 const char *name, int name_len, 6192 u64 ref_objectid, u64 objectid, 6193 umode_t mode, u64 *index) 6194 { 6195 struct btrfs_fs_info *fs_info = root->fs_info; 6196 struct inode *inode; 6197 struct btrfs_inode_item *inode_item; 6198 struct btrfs_key *location; 6199 struct btrfs_path *path; 6200 struct btrfs_inode_ref *ref; 6201 struct btrfs_key key[2]; 6202 u32 sizes[2]; 6203 int nitems = name ? 2 : 1; 6204 unsigned long ptr; 6205 int ret; 6206 6207 path = btrfs_alloc_path(); 6208 if (!path) 6209 return ERR_PTR(-ENOMEM); 6210 6211 inode = new_inode(fs_info->sb); 6212 if (!inode) { 6213 btrfs_free_path(path); 6214 return ERR_PTR(-ENOMEM); 6215 } 6216 6217 /* 6218 * O_TMPFILE, set link count to 0, so that after this point, 6219 * we fill in an inode item with the correct link count. 6220 */ 6221 if (!name) 6222 set_nlink(inode, 0); 6223 6224 /* 6225 * we have to initialize this early, so we can reclaim the inode 6226 * number if we fail afterwards in this function. 6227 */ 6228 inode->i_ino = objectid; 6229 6230 if (dir && name) { 6231 trace_btrfs_inode_request(dir); 6232 6233 ret = btrfs_set_inode_index(BTRFS_I(dir), index); 6234 if (ret) { 6235 btrfs_free_path(path); 6236 iput(inode); 6237 return ERR_PTR(ret); 6238 } 6239 } else if (dir) { 6240 *index = 0; 6241 } 6242 /* 6243 * index_cnt is ignored for everything but a dir, 6244 * btrfs_get_inode_index_count has an explanation for the magic 6245 * number 6246 */ 6247 BTRFS_I(inode)->index_cnt = 2; 6248 BTRFS_I(inode)->dir_index = *index; 6249 BTRFS_I(inode)->root = root; 6250 BTRFS_I(inode)->generation = trans->transid; 6251 inode->i_generation = BTRFS_I(inode)->generation; 6252 6253 /* 6254 * We could have gotten an inode number from somebody who was fsynced 6255 * and then removed in this same transaction, so let's just set full 6256 * sync since it will be a full sync anyway and this will blow away the 6257 * old info in the log. 6258 */ 6259 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 6260 6261 key[0].objectid = objectid; 6262 key[0].type = BTRFS_INODE_ITEM_KEY; 6263 key[0].offset = 0; 6264 6265 sizes[0] = sizeof(struct btrfs_inode_item); 6266 6267 if (name) { 6268 /* 6269 * Start new inodes with an inode_ref. This is slightly more 6270 * efficient for small numbers of hard links since they will 6271 * be packed into one item. Extended refs will kick in if we 6272 * add more hard links than can fit in the ref item. 6273 */ 6274 key[1].objectid = objectid; 6275 key[1].type = BTRFS_INODE_REF_KEY; 6276 key[1].offset = ref_objectid; 6277 6278 sizes[1] = name_len + sizeof(*ref); 6279 } 6280 6281 location = &BTRFS_I(inode)->location; 6282 location->objectid = objectid; 6283 location->offset = 0; 6284 location->type = BTRFS_INODE_ITEM_KEY; 6285 6286 ret = btrfs_insert_inode_locked(inode); 6287 if (ret < 0) 6288 goto fail; 6289 6290 path->leave_spinning = 1; 6291 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems); 6292 if (ret != 0) 6293 goto fail_unlock; 6294 6295 inode_init_owner(inode, dir, mode); 6296 inode_set_bytes(inode, 0); 6297 6298 inode->i_mtime = current_time(inode); 6299 inode->i_atime = inode->i_mtime; 6300 inode->i_ctime = inode->i_mtime; 6301 BTRFS_I(inode)->i_otime = inode->i_mtime; 6302 6303 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0], 6304 struct btrfs_inode_item); 6305 memzero_extent_buffer(path->nodes[0], (unsigned long)inode_item, 6306 sizeof(*inode_item)); 6307 fill_inode_item(trans, path->nodes[0], inode_item, inode); 6308 6309 if (name) { 6310 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, 6311 struct btrfs_inode_ref); 6312 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len); 6313 btrfs_set_inode_ref_index(path->nodes[0], ref, *index); 6314 ptr = (unsigned long)(ref + 1); 6315 write_extent_buffer(path->nodes[0], name, ptr, name_len); 6316 } 6317 6318 btrfs_mark_buffer_dirty(path->nodes[0]); 6319 btrfs_free_path(path); 6320 6321 btrfs_inherit_iflags(inode, dir); 6322 6323 if (S_ISREG(mode)) { 6324 if (btrfs_test_opt(fs_info, NODATASUM)) 6325 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; 6326 if (btrfs_test_opt(fs_info, NODATACOW)) 6327 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW | 6328 BTRFS_INODE_NODATASUM; 6329 } 6330 6331 inode_tree_add(inode); 6332 6333 trace_btrfs_inode_new(inode); 6334 btrfs_set_inode_last_trans(trans, inode); 6335 6336 btrfs_update_root_times(trans, root); 6337 6338 ret = btrfs_inode_inherit_props(trans, inode, dir); 6339 if (ret) 6340 btrfs_err(fs_info, 6341 "error inheriting props for ino %llu (root %llu): %d", 6342 btrfs_ino(BTRFS_I(inode)), root->root_key.objectid, ret); 6343 6344 return inode; 6345 6346 fail_unlock: 6347 unlock_new_inode(inode); 6348 fail: 6349 if (dir && name) 6350 BTRFS_I(dir)->index_cnt--; 6351 btrfs_free_path(path); 6352 iput(inode); 6353 return ERR_PTR(ret); 6354 } 6355 6356 static inline u8 btrfs_inode_type(struct inode *inode) 6357 { 6358 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT]; 6359 } 6360 6361 /* 6362 * utility function to add 'inode' into 'parent_inode' with 6363 * a give name and a given sequence number. 6364 * if 'add_backref' is true, also insert a backref from the 6365 * inode to the parent directory. 6366 */ 6367 int btrfs_add_link(struct btrfs_trans_handle *trans, 6368 struct btrfs_inode *parent_inode, struct btrfs_inode *inode, 6369 const char *name, int name_len, int add_backref, u64 index) 6370 { 6371 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb); 6372 int ret = 0; 6373 struct btrfs_key key; 6374 struct btrfs_root *root = parent_inode->root; 6375 u64 ino = btrfs_ino(inode); 6376 u64 parent_ino = btrfs_ino(parent_inode); 6377 6378 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6379 memcpy(&key, &inode->root->root_key, sizeof(key)); 6380 } else { 6381 key.objectid = ino; 6382 key.type = BTRFS_INODE_ITEM_KEY; 6383 key.offset = 0; 6384 } 6385 6386 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6387 ret = btrfs_add_root_ref(trans, fs_info, key.objectid, 6388 root->root_key.objectid, parent_ino, 6389 index, name, name_len); 6390 } else if (add_backref) { 6391 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino, 6392 parent_ino, index); 6393 } 6394 6395 /* Nothing to clean up yet */ 6396 if (ret) 6397 return ret; 6398 6399 ret = btrfs_insert_dir_item(trans, root, name, name_len, 6400 parent_inode, &key, 6401 btrfs_inode_type(&inode->vfs_inode), index); 6402 if (ret == -EEXIST || ret == -EOVERFLOW) 6403 goto fail_dir_item; 6404 else if (ret) { 6405 btrfs_abort_transaction(trans, ret); 6406 return ret; 6407 } 6408 6409 btrfs_i_size_write(parent_inode, parent_inode->vfs_inode.i_size + 6410 name_len * 2); 6411 inode_inc_iversion(&parent_inode->vfs_inode); 6412 parent_inode->vfs_inode.i_mtime = parent_inode->vfs_inode.i_ctime = 6413 current_time(&parent_inode->vfs_inode); 6414 ret = btrfs_update_inode(trans, root, &parent_inode->vfs_inode); 6415 if (ret) 6416 btrfs_abort_transaction(trans, ret); 6417 return ret; 6418 6419 fail_dir_item: 6420 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6421 u64 local_index; 6422 int err; 6423 err = btrfs_del_root_ref(trans, fs_info, key.objectid, 6424 root->root_key.objectid, parent_ino, 6425 &local_index, name, name_len); 6426 6427 } else if (add_backref) { 6428 u64 local_index; 6429 int err; 6430 6431 err = btrfs_del_inode_ref(trans, root, name, name_len, 6432 ino, parent_ino, &local_index); 6433 } 6434 return ret; 6435 } 6436 6437 static int btrfs_add_nondir(struct btrfs_trans_handle *trans, 6438 struct btrfs_inode *dir, struct dentry *dentry, 6439 struct btrfs_inode *inode, int backref, u64 index) 6440 { 6441 int err = btrfs_add_link(trans, dir, inode, 6442 dentry->d_name.name, dentry->d_name.len, 6443 backref, index); 6444 if (err > 0) 6445 err = -EEXIST; 6446 return err; 6447 } 6448 6449 static int btrfs_mknod(struct inode *dir, struct dentry *dentry, 6450 umode_t mode, dev_t rdev) 6451 { 6452 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 6453 struct btrfs_trans_handle *trans; 6454 struct btrfs_root *root = BTRFS_I(dir)->root; 6455 struct inode *inode = NULL; 6456 int err; 6457 int drop_inode = 0; 6458 u64 objectid; 6459 u64 index = 0; 6460 6461 /* 6462 * 2 for inode item and ref 6463 * 2 for dir items 6464 * 1 for xattr if selinux is on 6465 */ 6466 trans = btrfs_start_transaction(root, 5); 6467 if (IS_ERR(trans)) 6468 return PTR_ERR(trans); 6469 6470 err = btrfs_find_free_ino(root, &objectid); 6471 if (err) 6472 goto out_unlock; 6473 6474 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6475 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, 6476 mode, &index); 6477 if (IS_ERR(inode)) { 6478 err = PTR_ERR(inode); 6479 goto out_unlock; 6480 } 6481 6482 /* 6483 * If the active LSM wants to access the inode during 6484 * d_instantiate it needs these. Smack checks to see 6485 * if the filesystem supports xattrs by looking at the 6486 * ops vector. 6487 */ 6488 inode->i_op = &btrfs_special_inode_operations; 6489 init_special_inode(inode, inode->i_mode, rdev); 6490 6491 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6492 if (err) 6493 goto out_unlock_inode; 6494 6495 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 6496 0, index); 6497 if (err) { 6498 goto out_unlock_inode; 6499 } else { 6500 btrfs_update_inode(trans, root, inode); 6501 unlock_new_inode(inode); 6502 d_instantiate(dentry, inode); 6503 } 6504 6505 out_unlock: 6506 btrfs_end_transaction(trans); 6507 btrfs_balance_delayed_items(fs_info); 6508 btrfs_btree_balance_dirty(fs_info); 6509 if (drop_inode) { 6510 inode_dec_link_count(inode); 6511 iput(inode); 6512 } 6513 return err; 6514 6515 out_unlock_inode: 6516 drop_inode = 1; 6517 unlock_new_inode(inode); 6518 goto out_unlock; 6519 6520 } 6521 6522 static int btrfs_create(struct inode *dir, struct dentry *dentry, 6523 umode_t mode, bool excl) 6524 { 6525 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 6526 struct btrfs_trans_handle *trans; 6527 struct btrfs_root *root = BTRFS_I(dir)->root; 6528 struct inode *inode = NULL; 6529 int drop_inode_on_err = 0; 6530 int err; 6531 u64 objectid; 6532 u64 index = 0; 6533 6534 /* 6535 * 2 for inode item and ref 6536 * 2 for dir items 6537 * 1 for xattr if selinux is on 6538 */ 6539 trans = btrfs_start_transaction(root, 5); 6540 if (IS_ERR(trans)) 6541 return PTR_ERR(trans); 6542 6543 err = btrfs_find_free_ino(root, &objectid); 6544 if (err) 6545 goto out_unlock; 6546 6547 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6548 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, 6549 mode, &index); 6550 if (IS_ERR(inode)) { 6551 err = PTR_ERR(inode); 6552 goto out_unlock; 6553 } 6554 drop_inode_on_err = 1; 6555 /* 6556 * If the active LSM wants to access the inode during 6557 * d_instantiate it needs these. Smack checks to see 6558 * if the filesystem supports xattrs by looking at the 6559 * ops vector. 6560 */ 6561 inode->i_fop = &btrfs_file_operations; 6562 inode->i_op = &btrfs_file_inode_operations; 6563 inode->i_mapping->a_ops = &btrfs_aops; 6564 6565 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6566 if (err) 6567 goto out_unlock_inode; 6568 6569 err = btrfs_update_inode(trans, root, inode); 6570 if (err) 6571 goto out_unlock_inode; 6572 6573 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 6574 0, index); 6575 if (err) 6576 goto out_unlock_inode; 6577 6578 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 6579 unlock_new_inode(inode); 6580 d_instantiate(dentry, inode); 6581 6582 out_unlock: 6583 btrfs_end_transaction(trans); 6584 if (err && drop_inode_on_err) { 6585 inode_dec_link_count(inode); 6586 iput(inode); 6587 } 6588 btrfs_balance_delayed_items(fs_info); 6589 btrfs_btree_balance_dirty(fs_info); 6590 return err; 6591 6592 out_unlock_inode: 6593 unlock_new_inode(inode); 6594 goto out_unlock; 6595 6596 } 6597 6598 static int btrfs_link(struct dentry *old_dentry, struct inode *dir, 6599 struct dentry *dentry) 6600 { 6601 struct btrfs_trans_handle *trans = NULL; 6602 struct btrfs_root *root = BTRFS_I(dir)->root; 6603 struct inode *inode = d_inode(old_dentry); 6604 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 6605 u64 index; 6606 int err; 6607 int drop_inode = 0; 6608 6609 /* do not allow sys_link's with other subvols of the same device */ 6610 if (root->objectid != BTRFS_I(inode)->root->objectid) 6611 return -EXDEV; 6612 6613 if (inode->i_nlink >= BTRFS_LINK_MAX) 6614 return -EMLINK; 6615 6616 err = btrfs_set_inode_index(BTRFS_I(dir), &index); 6617 if (err) 6618 goto fail; 6619 6620 /* 6621 * 2 items for inode and inode ref 6622 * 2 items for dir items 6623 * 1 item for parent inode 6624 */ 6625 trans = btrfs_start_transaction(root, 5); 6626 if (IS_ERR(trans)) { 6627 err = PTR_ERR(trans); 6628 trans = NULL; 6629 goto fail; 6630 } 6631 6632 /* There are several dir indexes for this inode, clear the cache. */ 6633 BTRFS_I(inode)->dir_index = 0ULL; 6634 inc_nlink(inode); 6635 inode_inc_iversion(inode); 6636 inode->i_ctime = current_time(inode); 6637 ihold(inode); 6638 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags); 6639 6640 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 6641 1, index); 6642 6643 if (err) { 6644 drop_inode = 1; 6645 } else { 6646 struct dentry *parent = dentry->d_parent; 6647 err = btrfs_update_inode(trans, root, inode); 6648 if (err) 6649 goto fail; 6650 if (inode->i_nlink == 1) { 6651 /* 6652 * If new hard link count is 1, it's a file created 6653 * with open(2) O_TMPFILE flag. 6654 */ 6655 err = btrfs_orphan_del(trans, BTRFS_I(inode)); 6656 if (err) 6657 goto fail; 6658 } 6659 d_instantiate(dentry, inode); 6660 btrfs_log_new_name(trans, BTRFS_I(inode), NULL, parent); 6661 } 6662 6663 btrfs_balance_delayed_items(fs_info); 6664 fail: 6665 if (trans) 6666 btrfs_end_transaction(trans); 6667 if (drop_inode) { 6668 inode_dec_link_count(inode); 6669 iput(inode); 6670 } 6671 btrfs_btree_balance_dirty(fs_info); 6672 return err; 6673 } 6674 6675 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 6676 { 6677 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 6678 struct inode *inode = NULL; 6679 struct btrfs_trans_handle *trans; 6680 struct btrfs_root *root = BTRFS_I(dir)->root; 6681 int err = 0; 6682 int drop_on_err = 0; 6683 u64 objectid = 0; 6684 u64 index = 0; 6685 6686 /* 6687 * 2 items for inode and ref 6688 * 2 items for dir items 6689 * 1 for xattr if selinux is on 6690 */ 6691 trans = btrfs_start_transaction(root, 5); 6692 if (IS_ERR(trans)) 6693 return PTR_ERR(trans); 6694 6695 err = btrfs_find_free_ino(root, &objectid); 6696 if (err) 6697 goto out_fail; 6698 6699 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6700 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, 6701 S_IFDIR | mode, &index); 6702 if (IS_ERR(inode)) { 6703 err = PTR_ERR(inode); 6704 goto out_fail; 6705 } 6706 6707 drop_on_err = 1; 6708 /* these must be set before we unlock the inode */ 6709 inode->i_op = &btrfs_dir_inode_operations; 6710 inode->i_fop = &btrfs_dir_file_operations; 6711 6712 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6713 if (err) 6714 goto out_fail_inode; 6715 6716 btrfs_i_size_write(BTRFS_I(inode), 0); 6717 err = btrfs_update_inode(trans, root, inode); 6718 if (err) 6719 goto out_fail_inode; 6720 6721 err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), 6722 dentry->d_name.name, 6723 dentry->d_name.len, 0, index); 6724 if (err) 6725 goto out_fail_inode; 6726 6727 d_instantiate(dentry, inode); 6728 /* 6729 * mkdir is special. We're unlocking after we call d_instantiate 6730 * to avoid a race with nfsd calling d_instantiate. 6731 */ 6732 unlock_new_inode(inode); 6733 drop_on_err = 0; 6734 6735 out_fail: 6736 btrfs_end_transaction(trans); 6737 if (drop_on_err) { 6738 inode_dec_link_count(inode); 6739 iput(inode); 6740 } 6741 btrfs_balance_delayed_items(fs_info); 6742 btrfs_btree_balance_dirty(fs_info); 6743 return err; 6744 6745 out_fail_inode: 6746 unlock_new_inode(inode); 6747 goto out_fail; 6748 } 6749 6750 /* Find next extent map of a given extent map, caller needs to ensure locks */ 6751 static struct extent_map *next_extent_map(struct extent_map *em) 6752 { 6753 struct rb_node *next; 6754 6755 next = rb_next(&em->rb_node); 6756 if (!next) 6757 return NULL; 6758 return container_of(next, struct extent_map, rb_node); 6759 } 6760 6761 static struct extent_map *prev_extent_map(struct extent_map *em) 6762 { 6763 struct rb_node *prev; 6764 6765 prev = rb_prev(&em->rb_node); 6766 if (!prev) 6767 return NULL; 6768 return container_of(prev, struct extent_map, rb_node); 6769 } 6770 6771 /* helper for btfs_get_extent. Given an existing extent in the tree, 6772 * the existing extent is the nearest extent to map_start, 6773 * and an extent that you want to insert, deal with overlap and insert 6774 * the best fitted new extent into the tree. 6775 */ 6776 static int merge_extent_mapping(struct extent_map_tree *em_tree, 6777 struct extent_map *existing, 6778 struct extent_map *em, 6779 u64 map_start) 6780 { 6781 struct extent_map *prev; 6782 struct extent_map *next; 6783 u64 start; 6784 u64 end; 6785 u64 start_diff; 6786 6787 BUG_ON(map_start < em->start || map_start >= extent_map_end(em)); 6788 6789 if (existing->start > map_start) { 6790 next = existing; 6791 prev = prev_extent_map(next); 6792 } else { 6793 prev = existing; 6794 next = next_extent_map(prev); 6795 } 6796 6797 start = prev ? extent_map_end(prev) : em->start; 6798 start = max_t(u64, start, em->start); 6799 end = next ? next->start : extent_map_end(em); 6800 end = min_t(u64, end, extent_map_end(em)); 6801 start_diff = start - em->start; 6802 em->start = start; 6803 em->len = end - start; 6804 if (em->block_start < EXTENT_MAP_LAST_BYTE && 6805 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { 6806 em->block_start += start_diff; 6807 em->block_len -= start_diff; 6808 } 6809 return add_extent_mapping(em_tree, em, 0); 6810 } 6811 6812 static noinline int uncompress_inline(struct btrfs_path *path, 6813 struct page *page, 6814 size_t pg_offset, u64 extent_offset, 6815 struct btrfs_file_extent_item *item) 6816 { 6817 int ret; 6818 struct extent_buffer *leaf = path->nodes[0]; 6819 char *tmp; 6820 size_t max_size; 6821 unsigned long inline_size; 6822 unsigned long ptr; 6823 int compress_type; 6824 6825 WARN_ON(pg_offset != 0); 6826 compress_type = btrfs_file_extent_compression(leaf, item); 6827 max_size = btrfs_file_extent_ram_bytes(leaf, item); 6828 inline_size = btrfs_file_extent_inline_item_len(leaf, 6829 btrfs_item_nr(path->slots[0])); 6830 tmp = kmalloc(inline_size, GFP_NOFS); 6831 if (!tmp) 6832 return -ENOMEM; 6833 ptr = btrfs_file_extent_inline_start(item); 6834 6835 read_extent_buffer(leaf, tmp, ptr, inline_size); 6836 6837 max_size = min_t(unsigned long, PAGE_SIZE, max_size); 6838 ret = btrfs_decompress(compress_type, tmp, page, 6839 extent_offset, inline_size, max_size); 6840 6841 /* 6842 * decompression code contains a memset to fill in any space between the end 6843 * of the uncompressed data and the end of max_size in case the decompressed 6844 * data ends up shorter than ram_bytes. That doesn't cover the hole between 6845 * the end of an inline extent and the beginning of the next block, so we 6846 * cover that region here. 6847 */ 6848 6849 if (max_size + pg_offset < PAGE_SIZE) { 6850 char *map = kmap(page); 6851 memset(map + pg_offset + max_size, 0, PAGE_SIZE - max_size - pg_offset); 6852 kunmap(page); 6853 } 6854 kfree(tmp); 6855 return ret; 6856 } 6857 6858 /* 6859 * a bit scary, this does extent mapping from logical file offset to the disk. 6860 * the ugly parts come from merging extents from the disk with the in-ram 6861 * representation. This gets more complex because of the data=ordered code, 6862 * where the in-ram extents might be locked pending data=ordered completion. 6863 * 6864 * This also copies inline extents directly into the page. 6865 */ 6866 struct extent_map *btrfs_get_extent(struct btrfs_inode *inode, 6867 struct page *page, 6868 size_t pg_offset, u64 start, u64 len, 6869 int create) 6870 { 6871 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb); 6872 int ret; 6873 int err = 0; 6874 u64 extent_start = 0; 6875 u64 extent_end = 0; 6876 u64 objectid = btrfs_ino(inode); 6877 u32 found_type; 6878 struct btrfs_path *path = NULL; 6879 struct btrfs_root *root = inode->root; 6880 struct btrfs_file_extent_item *item; 6881 struct extent_buffer *leaf; 6882 struct btrfs_key found_key; 6883 struct extent_map *em = NULL; 6884 struct extent_map_tree *em_tree = &inode->extent_tree; 6885 struct extent_io_tree *io_tree = &inode->io_tree; 6886 struct btrfs_trans_handle *trans = NULL; 6887 const bool new_inline = !page || create; 6888 6889 again: 6890 read_lock(&em_tree->lock); 6891 em = lookup_extent_mapping(em_tree, start, len); 6892 if (em) 6893 em->bdev = fs_info->fs_devices->latest_bdev; 6894 read_unlock(&em_tree->lock); 6895 6896 if (em) { 6897 if (em->start > start || em->start + em->len <= start) 6898 free_extent_map(em); 6899 else if (em->block_start == EXTENT_MAP_INLINE && page) 6900 free_extent_map(em); 6901 else 6902 goto out; 6903 } 6904 em = alloc_extent_map(); 6905 if (!em) { 6906 err = -ENOMEM; 6907 goto out; 6908 } 6909 em->bdev = fs_info->fs_devices->latest_bdev; 6910 em->start = EXTENT_MAP_HOLE; 6911 em->orig_start = EXTENT_MAP_HOLE; 6912 em->len = (u64)-1; 6913 em->block_len = (u64)-1; 6914 6915 if (!path) { 6916 path = btrfs_alloc_path(); 6917 if (!path) { 6918 err = -ENOMEM; 6919 goto out; 6920 } 6921 /* 6922 * Chances are we'll be called again, so go ahead and do 6923 * readahead 6924 */ 6925 path->reada = READA_FORWARD; 6926 } 6927 6928 ret = btrfs_lookup_file_extent(trans, root, path, 6929 objectid, start, trans != NULL); 6930 if (ret < 0) { 6931 err = ret; 6932 goto out; 6933 } 6934 6935 if (ret != 0) { 6936 if (path->slots[0] == 0) 6937 goto not_found; 6938 path->slots[0]--; 6939 } 6940 6941 leaf = path->nodes[0]; 6942 item = btrfs_item_ptr(leaf, path->slots[0], 6943 struct btrfs_file_extent_item); 6944 /* are we inside the extent that was found? */ 6945 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6946 found_type = found_key.type; 6947 if (found_key.objectid != objectid || 6948 found_type != BTRFS_EXTENT_DATA_KEY) { 6949 /* 6950 * If we backup past the first extent we want to move forward 6951 * and see if there is an extent in front of us, otherwise we'll 6952 * say there is a hole for our whole search range which can 6953 * cause problems. 6954 */ 6955 extent_end = start; 6956 goto next; 6957 } 6958 6959 found_type = btrfs_file_extent_type(leaf, item); 6960 extent_start = found_key.offset; 6961 if (found_type == BTRFS_FILE_EXTENT_REG || 6962 found_type == BTRFS_FILE_EXTENT_PREALLOC) { 6963 extent_end = extent_start + 6964 btrfs_file_extent_num_bytes(leaf, item); 6965 6966 trace_btrfs_get_extent_show_fi_regular(inode, leaf, item, 6967 extent_start); 6968 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { 6969 size_t size; 6970 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item); 6971 extent_end = ALIGN(extent_start + size, 6972 fs_info->sectorsize); 6973 6974 trace_btrfs_get_extent_show_fi_inline(inode, leaf, item, 6975 path->slots[0], 6976 extent_start); 6977 } 6978 next: 6979 if (start >= extent_end) { 6980 path->slots[0]++; 6981 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 6982 ret = btrfs_next_leaf(root, path); 6983 if (ret < 0) { 6984 err = ret; 6985 goto out; 6986 } 6987 if (ret > 0) 6988 goto not_found; 6989 leaf = path->nodes[0]; 6990 } 6991 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6992 if (found_key.objectid != objectid || 6993 found_key.type != BTRFS_EXTENT_DATA_KEY) 6994 goto not_found; 6995 if (start + len <= found_key.offset) 6996 goto not_found; 6997 if (start > found_key.offset) 6998 goto next; 6999 em->start = start; 7000 em->orig_start = start; 7001 em->len = found_key.offset - start; 7002 goto not_found_em; 7003 } 7004 7005 btrfs_extent_item_to_extent_map(inode, path, item, 7006 new_inline, em); 7007 7008 if (found_type == BTRFS_FILE_EXTENT_REG || 7009 found_type == BTRFS_FILE_EXTENT_PREALLOC) { 7010 goto insert; 7011 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { 7012 unsigned long ptr; 7013 char *map; 7014 size_t size; 7015 size_t extent_offset; 7016 size_t copy_size; 7017 7018 if (new_inline) 7019 goto out; 7020 7021 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item); 7022 extent_offset = page_offset(page) + pg_offset - extent_start; 7023 copy_size = min_t(u64, PAGE_SIZE - pg_offset, 7024 size - extent_offset); 7025 em->start = extent_start + extent_offset; 7026 em->len = ALIGN(copy_size, fs_info->sectorsize); 7027 em->orig_block_len = em->len; 7028 em->orig_start = em->start; 7029 ptr = btrfs_file_extent_inline_start(item) + extent_offset; 7030 if (create == 0 && !PageUptodate(page)) { 7031 if (btrfs_file_extent_compression(leaf, item) != 7032 BTRFS_COMPRESS_NONE) { 7033 ret = uncompress_inline(path, page, pg_offset, 7034 extent_offset, item); 7035 if (ret) { 7036 err = ret; 7037 goto out; 7038 } 7039 } else { 7040 map = kmap(page); 7041 read_extent_buffer(leaf, map + pg_offset, ptr, 7042 copy_size); 7043 if (pg_offset + copy_size < PAGE_SIZE) { 7044 memset(map + pg_offset + copy_size, 0, 7045 PAGE_SIZE - pg_offset - 7046 copy_size); 7047 } 7048 kunmap(page); 7049 } 7050 flush_dcache_page(page); 7051 } else if (create && PageUptodate(page)) { 7052 BUG(); 7053 if (!trans) { 7054 kunmap(page); 7055 free_extent_map(em); 7056 em = NULL; 7057 7058 btrfs_release_path(path); 7059 trans = btrfs_join_transaction(root); 7060 7061 if (IS_ERR(trans)) 7062 return ERR_CAST(trans); 7063 goto again; 7064 } 7065 map = kmap(page); 7066 write_extent_buffer(leaf, map + pg_offset, ptr, 7067 copy_size); 7068 kunmap(page); 7069 btrfs_mark_buffer_dirty(leaf); 7070 } 7071 set_extent_uptodate(io_tree, em->start, 7072 extent_map_end(em) - 1, NULL, GFP_NOFS); 7073 goto insert; 7074 } 7075 not_found: 7076 em->start = start; 7077 em->orig_start = start; 7078 em->len = len; 7079 not_found_em: 7080 em->block_start = EXTENT_MAP_HOLE; 7081 set_bit(EXTENT_FLAG_VACANCY, &em->flags); 7082 insert: 7083 btrfs_release_path(path); 7084 if (em->start > start || extent_map_end(em) <= start) { 7085 btrfs_err(fs_info, 7086 "bad extent! em: [%llu %llu] passed [%llu %llu]", 7087 em->start, em->len, start, len); 7088 err = -EIO; 7089 goto out; 7090 } 7091 7092 err = 0; 7093 write_lock(&em_tree->lock); 7094 ret = add_extent_mapping(em_tree, em, 0); 7095 /* it is possible that someone inserted the extent into the tree 7096 * while we had the lock dropped. It is also possible that 7097 * an overlapping map exists in the tree 7098 */ 7099 if (ret == -EEXIST) { 7100 struct extent_map *existing; 7101 7102 ret = 0; 7103 7104 existing = search_extent_mapping(em_tree, start, len); 7105 /* 7106 * existing will always be non-NULL, since there must be 7107 * extent causing the -EEXIST. 7108 */ 7109 if (existing->start == em->start && 7110 extent_map_end(existing) >= extent_map_end(em) && 7111 em->block_start == existing->block_start) { 7112 /* 7113 * The existing extent map already encompasses the 7114 * entire extent map we tried to add. 7115 */ 7116 free_extent_map(em); 7117 em = existing; 7118 err = 0; 7119 7120 } else if (start >= extent_map_end(existing) || 7121 start <= existing->start) { 7122 /* 7123 * The existing extent map is the one nearest to 7124 * the [start, start + len) range which overlaps 7125 */ 7126 err = merge_extent_mapping(em_tree, existing, 7127 em, start); 7128 free_extent_map(existing); 7129 if (err) { 7130 free_extent_map(em); 7131 em = NULL; 7132 } 7133 } else { 7134 free_extent_map(em); 7135 em = existing; 7136 err = 0; 7137 } 7138 } 7139 write_unlock(&em_tree->lock); 7140 out: 7141 7142 trace_btrfs_get_extent(root, inode, em); 7143 7144 btrfs_free_path(path); 7145 if (trans) { 7146 ret = btrfs_end_transaction(trans); 7147 if (!err) 7148 err = ret; 7149 } 7150 if (err) { 7151 free_extent_map(em); 7152 return ERR_PTR(err); 7153 } 7154 BUG_ON(!em); /* Error is always set */ 7155 return em; 7156 } 7157 7158 struct extent_map *btrfs_get_extent_fiemap(struct btrfs_inode *inode, 7159 struct page *page, 7160 size_t pg_offset, u64 start, u64 len, 7161 int create) 7162 { 7163 struct extent_map *em; 7164 struct extent_map *hole_em = NULL; 7165 u64 range_start = start; 7166 u64 end; 7167 u64 found; 7168 u64 found_end; 7169 int err = 0; 7170 7171 em = btrfs_get_extent(inode, page, pg_offset, start, len, create); 7172 if (IS_ERR(em)) 7173 return em; 7174 /* 7175 * If our em maps to: 7176 * - a hole or 7177 * - a pre-alloc extent, 7178 * there might actually be delalloc bytes behind it. 7179 */ 7180 if (em->block_start != EXTENT_MAP_HOLE && 7181 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7182 return em; 7183 else 7184 hole_em = em; 7185 7186 /* check to see if we've wrapped (len == -1 or similar) */ 7187 end = start + len; 7188 if (end < start) 7189 end = (u64)-1; 7190 else 7191 end -= 1; 7192 7193 em = NULL; 7194 7195 /* ok, we didn't find anything, lets look for delalloc */ 7196 found = count_range_bits(&inode->io_tree, &range_start, 7197 end, len, EXTENT_DELALLOC, 1); 7198 found_end = range_start + found; 7199 if (found_end < range_start) 7200 found_end = (u64)-1; 7201 7202 /* 7203 * we didn't find anything useful, return 7204 * the original results from get_extent() 7205 */ 7206 if (range_start > end || found_end <= start) { 7207 em = hole_em; 7208 hole_em = NULL; 7209 goto out; 7210 } 7211 7212 /* adjust the range_start to make sure it doesn't 7213 * go backwards from the start they passed in 7214 */ 7215 range_start = max(start, range_start); 7216 found = found_end - range_start; 7217 7218 if (found > 0) { 7219 u64 hole_start = start; 7220 u64 hole_len = len; 7221 7222 em = alloc_extent_map(); 7223 if (!em) { 7224 err = -ENOMEM; 7225 goto out; 7226 } 7227 /* 7228 * when btrfs_get_extent can't find anything it 7229 * returns one huge hole 7230 * 7231 * make sure what it found really fits our range, and 7232 * adjust to make sure it is based on the start from 7233 * the caller 7234 */ 7235 if (hole_em) { 7236 u64 calc_end = extent_map_end(hole_em); 7237 7238 if (calc_end <= start || (hole_em->start > end)) { 7239 free_extent_map(hole_em); 7240 hole_em = NULL; 7241 } else { 7242 hole_start = max(hole_em->start, start); 7243 hole_len = calc_end - hole_start; 7244 } 7245 } 7246 em->bdev = NULL; 7247 if (hole_em && range_start > hole_start) { 7248 /* our hole starts before our delalloc, so we 7249 * have to return just the parts of the hole 7250 * that go until the delalloc starts 7251 */ 7252 em->len = min(hole_len, 7253 range_start - hole_start); 7254 em->start = hole_start; 7255 em->orig_start = hole_start; 7256 /* 7257 * don't adjust block start at all, 7258 * it is fixed at EXTENT_MAP_HOLE 7259 */ 7260 em->block_start = hole_em->block_start; 7261 em->block_len = hole_len; 7262 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags)) 7263 set_bit(EXTENT_FLAG_PREALLOC, &em->flags); 7264 } else { 7265 em->start = range_start; 7266 em->len = found; 7267 em->orig_start = range_start; 7268 em->block_start = EXTENT_MAP_DELALLOC; 7269 em->block_len = found; 7270 } 7271 } else if (hole_em) { 7272 return hole_em; 7273 } 7274 out: 7275 7276 free_extent_map(hole_em); 7277 if (err) { 7278 free_extent_map(em); 7279 return ERR_PTR(err); 7280 } 7281 return em; 7282 } 7283 7284 static struct extent_map *btrfs_create_dio_extent(struct inode *inode, 7285 const u64 start, 7286 const u64 len, 7287 const u64 orig_start, 7288 const u64 block_start, 7289 const u64 block_len, 7290 const u64 orig_block_len, 7291 const u64 ram_bytes, 7292 const int type) 7293 { 7294 struct extent_map *em = NULL; 7295 int ret; 7296 7297 if (type != BTRFS_ORDERED_NOCOW) { 7298 em = create_io_em(inode, start, len, orig_start, 7299 block_start, block_len, orig_block_len, 7300 ram_bytes, 7301 BTRFS_COMPRESS_NONE, /* compress_type */ 7302 type); 7303 if (IS_ERR(em)) 7304 goto out; 7305 } 7306 ret = btrfs_add_ordered_extent_dio(inode, start, block_start, 7307 len, block_len, type); 7308 if (ret) { 7309 if (em) { 7310 free_extent_map(em); 7311 btrfs_drop_extent_cache(BTRFS_I(inode), start, 7312 start + len - 1, 0); 7313 } 7314 em = ERR_PTR(ret); 7315 } 7316 out: 7317 7318 return em; 7319 } 7320 7321 static struct extent_map *btrfs_new_extent_direct(struct inode *inode, 7322 u64 start, u64 len) 7323 { 7324 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7325 struct btrfs_root *root = BTRFS_I(inode)->root; 7326 struct extent_map *em; 7327 struct btrfs_key ins; 7328 u64 alloc_hint; 7329 int ret; 7330 7331 alloc_hint = get_extent_allocation_hint(inode, start, len); 7332 ret = btrfs_reserve_extent(root, len, len, fs_info->sectorsize, 7333 0, alloc_hint, &ins, 1, 1); 7334 if (ret) 7335 return ERR_PTR(ret); 7336 7337 em = btrfs_create_dio_extent(inode, start, ins.offset, start, 7338 ins.objectid, ins.offset, ins.offset, 7339 ins.offset, BTRFS_ORDERED_REGULAR); 7340 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 7341 if (IS_ERR(em)) 7342 btrfs_free_reserved_extent(fs_info, ins.objectid, 7343 ins.offset, 1); 7344 7345 return em; 7346 } 7347 7348 /* 7349 * returns 1 when the nocow is safe, < 1 on error, 0 if the 7350 * block must be cow'd 7351 */ 7352 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len, 7353 u64 *orig_start, u64 *orig_block_len, 7354 u64 *ram_bytes) 7355 { 7356 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7357 struct btrfs_path *path; 7358 int ret; 7359 struct extent_buffer *leaf; 7360 struct btrfs_root *root = BTRFS_I(inode)->root; 7361 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 7362 struct btrfs_file_extent_item *fi; 7363 struct btrfs_key key; 7364 u64 disk_bytenr; 7365 u64 backref_offset; 7366 u64 extent_end; 7367 u64 num_bytes; 7368 int slot; 7369 int found_type; 7370 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW); 7371 7372 path = btrfs_alloc_path(); 7373 if (!path) 7374 return -ENOMEM; 7375 7376 ret = btrfs_lookup_file_extent(NULL, root, path, 7377 btrfs_ino(BTRFS_I(inode)), offset, 0); 7378 if (ret < 0) 7379 goto out; 7380 7381 slot = path->slots[0]; 7382 if (ret == 1) { 7383 if (slot == 0) { 7384 /* can't find the item, must cow */ 7385 ret = 0; 7386 goto out; 7387 } 7388 slot--; 7389 } 7390 ret = 0; 7391 leaf = path->nodes[0]; 7392 btrfs_item_key_to_cpu(leaf, &key, slot); 7393 if (key.objectid != btrfs_ino(BTRFS_I(inode)) || 7394 key.type != BTRFS_EXTENT_DATA_KEY) { 7395 /* not our file or wrong item type, must cow */ 7396 goto out; 7397 } 7398 7399 if (key.offset > offset) { 7400 /* Wrong offset, must cow */ 7401 goto out; 7402 } 7403 7404 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); 7405 found_type = btrfs_file_extent_type(leaf, fi); 7406 if (found_type != BTRFS_FILE_EXTENT_REG && 7407 found_type != BTRFS_FILE_EXTENT_PREALLOC) { 7408 /* not a regular extent, must cow */ 7409 goto out; 7410 } 7411 7412 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG) 7413 goto out; 7414 7415 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); 7416 if (extent_end <= offset) 7417 goto out; 7418 7419 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 7420 if (disk_bytenr == 0) 7421 goto out; 7422 7423 if (btrfs_file_extent_compression(leaf, fi) || 7424 btrfs_file_extent_encryption(leaf, fi) || 7425 btrfs_file_extent_other_encoding(leaf, fi)) 7426 goto out; 7427 7428 backref_offset = btrfs_file_extent_offset(leaf, fi); 7429 7430 if (orig_start) { 7431 *orig_start = key.offset - backref_offset; 7432 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi); 7433 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); 7434 } 7435 7436 if (btrfs_extent_readonly(fs_info, disk_bytenr)) 7437 goto out; 7438 7439 num_bytes = min(offset + *len, extent_end) - offset; 7440 if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) { 7441 u64 range_end; 7442 7443 range_end = round_up(offset + num_bytes, 7444 root->fs_info->sectorsize) - 1; 7445 ret = test_range_bit(io_tree, offset, range_end, 7446 EXTENT_DELALLOC, 0, NULL); 7447 if (ret) { 7448 ret = -EAGAIN; 7449 goto out; 7450 } 7451 } 7452 7453 btrfs_release_path(path); 7454 7455 /* 7456 * look for other files referencing this extent, if we 7457 * find any we must cow 7458 */ 7459 7460 ret = btrfs_cross_ref_exist(root, btrfs_ino(BTRFS_I(inode)), 7461 key.offset - backref_offset, disk_bytenr); 7462 if (ret) { 7463 ret = 0; 7464 goto out; 7465 } 7466 7467 /* 7468 * adjust disk_bytenr and num_bytes to cover just the bytes 7469 * in this extent we are about to write. If there 7470 * are any csums in that range we have to cow in order 7471 * to keep the csums correct 7472 */ 7473 disk_bytenr += backref_offset; 7474 disk_bytenr += offset - key.offset; 7475 if (csum_exist_in_range(fs_info, disk_bytenr, num_bytes)) 7476 goto out; 7477 /* 7478 * all of the above have passed, it is safe to overwrite this extent 7479 * without cow 7480 */ 7481 *len = num_bytes; 7482 ret = 1; 7483 out: 7484 btrfs_free_path(path); 7485 return ret; 7486 } 7487 7488 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end) 7489 { 7490 struct radix_tree_root *root = &inode->i_mapping->page_tree; 7491 bool found = false; 7492 void **pagep = NULL; 7493 struct page *page = NULL; 7494 unsigned long start_idx; 7495 unsigned long end_idx; 7496 7497 start_idx = start >> PAGE_SHIFT; 7498 7499 /* 7500 * end is the last byte in the last page. end == start is legal 7501 */ 7502 end_idx = end >> PAGE_SHIFT; 7503 7504 rcu_read_lock(); 7505 7506 /* Most of the code in this while loop is lifted from 7507 * find_get_page. It's been modified to begin searching from a 7508 * page and return just the first page found in that range. If the 7509 * found idx is less than or equal to the end idx then we know that 7510 * a page exists. If no pages are found or if those pages are 7511 * outside of the range then we're fine (yay!) */ 7512 while (page == NULL && 7513 radix_tree_gang_lookup_slot(root, &pagep, NULL, start_idx, 1)) { 7514 page = radix_tree_deref_slot(pagep); 7515 if (unlikely(!page)) 7516 break; 7517 7518 if (radix_tree_exception(page)) { 7519 if (radix_tree_deref_retry(page)) { 7520 page = NULL; 7521 continue; 7522 } 7523 /* 7524 * Otherwise, shmem/tmpfs must be storing a swap entry 7525 * here as an exceptional entry: so return it without 7526 * attempting to raise page count. 7527 */ 7528 page = NULL; 7529 break; /* TODO: Is this relevant for this use case? */ 7530 } 7531 7532 if (!page_cache_get_speculative(page)) { 7533 page = NULL; 7534 continue; 7535 } 7536 7537 /* 7538 * Has the page moved? 7539 * This is part of the lockless pagecache protocol. See 7540 * include/linux/pagemap.h for details. 7541 */ 7542 if (unlikely(page != *pagep)) { 7543 put_page(page); 7544 page = NULL; 7545 } 7546 } 7547 7548 if (page) { 7549 if (page->index <= end_idx) 7550 found = true; 7551 put_page(page); 7552 } 7553 7554 rcu_read_unlock(); 7555 return found; 7556 } 7557 7558 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, 7559 struct extent_state **cached_state, int writing) 7560 { 7561 struct btrfs_ordered_extent *ordered; 7562 int ret = 0; 7563 7564 while (1) { 7565 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7566 cached_state); 7567 /* 7568 * We're concerned with the entire range that we're going to be 7569 * doing DIO to, so we need to make sure there's no ordered 7570 * extents in this range. 7571 */ 7572 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), lockstart, 7573 lockend - lockstart + 1); 7574 7575 /* 7576 * We need to make sure there are no buffered pages in this 7577 * range either, we could have raced between the invalidate in 7578 * generic_file_direct_write and locking the extent. The 7579 * invalidate needs to happen so that reads after a write do not 7580 * get stale data. 7581 */ 7582 if (!ordered && 7583 (!writing || 7584 !btrfs_page_exists_in_range(inode, lockstart, lockend))) 7585 break; 7586 7587 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7588 cached_state, GFP_NOFS); 7589 7590 if (ordered) { 7591 /* 7592 * If we are doing a DIO read and the ordered extent we 7593 * found is for a buffered write, we can not wait for it 7594 * to complete and retry, because if we do so we can 7595 * deadlock with concurrent buffered writes on page 7596 * locks. This happens only if our DIO read covers more 7597 * than one extent map, if at this point has already 7598 * created an ordered extent for a previous extent map 7599 * and locked its range in the inode's io tree, and a 7600 * concurrent write against that previous extent map's 7601 * range and this range started (we unlock the ranges 7602 * in the io tree only when the bios complete and 7603 * buffered writes always lock pages before attempting 7604 * to lock range in the io tree). 7605 */ 7606 if (writing || 7607 test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) 7608 btrfs_start_ordered_extent(inode, ordered, 1); 7609 else 7610 ret = -ENOTBLK; 7611 btrfs_put_ordered_extent(ordered); 7612 } else { 7613 /* 7614 * We could trigger writeback for this range (and wait 7615 * for it to complete) and then invalidate the pages for 7616 * this range (through invalidate_inode_pages2_range()), 7617 * but that can lead us to a deadlock with a concurrent 7618 * call to readpages() (a buffered read or a defrag call 7619 * triggered a readahead) on a page lock due to an 7620 * ordered dio extent we created before but did not have 7621 * yet a corresponding bio submitted (whence it can not 7622 * complete), which makes readpages() wait for that 7623 * ordered extent to complete while holding a lock on 7624 * that page. 7625 */ 7626 ret = -ENOTBLK; 7627 } 7628 7629 if (ret) 7630 break; 7631 7632 cond_resched(); 7633 } 7634 7635 return ret; 7636 } 7637 7638 /* The callers of this must take lock_extent() */ 7639 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len, 7640 u64 orig_start, u64 block_start, 7641 u64 block_len, u64 orig_block_len, 7642 u64 ram_bytes, int compress_type, 7643 int type) 7644 { 7645 struct extent_map_tree *em_tree; 7646 struct extent_map *em; 7647 struct btrfs_root *root = BTRFS_I(inode)->root; 7648 int ret; 7649 7650 ASSERT(type == BTRFS_ORDERED_PREALLOC || 7651 type == BTRFS_ORDERED_COMPRESSED || 7652 type == BTRFS_ORDERED_NOCOW || 7653 type == BTRFS_ORDERED_REGULAR); 7654 7655 em_tree = &BTRFS_I(inode)->extent_tree; 7656 em = alloc_extent_map(); 7657 if (!em) 7658 return ERR_PTR(-ENOMEM); 7659 7660 em->start = start; 7661 em->orig_start = orig_start; 7662 em->len = len; 7663 em->block_len = block_len; 7664 em->block_start = block_start; 7665 em->bdev = root->fs_info->fs_devices->latest_bdev; 7666 em->orig_block_len = orig_block_len; 7667 em->ram_bytes = ram_bytes; 7668 em->generation = -1; 7669 set_bit(EXTENT_FLAG_PINNED, &em->flags); 7670 if (type == BTRFS_ORDERED_PREALLOC) { 7671 set_bit(EXTENT_FLAG_FILLING, &em->flags); 7672 } else if (type == BTRFS_ORDERED_COMPRESSED) { 7673 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); 7674 em->compress_type = compress_type; 7675 } 7676 7677 do { 7678 btrfs_drop_extent_cache(BTRFS_I(inode), em->start, 7679 em->start + em->len - 1, 0); 7680 write_lock(&em_tree->lock); 7681 ret = add_extent_mapping(em_tree, em, 1); 7682 write_unlock(&em_tree->lock); 7683 /* 7684 * The caller has taken lock_extent(), who could race with us 7685 * to add em? 7686 */ 7687 } while (ret == -EEXIST); 7688 7689 if (ret) { 7690 free_extent_map(em); 7691 return ERR_PTR(ret); 7692 } 7693 7694 /* em got 2 refs now, callers needs to do free_extent_map once. */ 7695 return em; 7696 } 7697 7698 static void adjust_dio_outstanding_extents(struct inode *inode, 7699 struct btrfs_dio_data *dio_data, 7700 const u64 len) 7701 { 7702 unsigned num_extents = count_max_extents(len); 7703 7704 /* 7705 * If we have an outstanding_extents count still set then we're 7706 * within our reservation, otherwise we need to adjust our inode 7707 * counter appropriately. 7708 */ 7709 if (dio_data->outstanding_extents >= num_extents) { 7710 dio_data->outstanding_extents -= num_extents; 7711 } else { 7712 /* 7713 * If dio write length has been split due to no large enough 7714 * contiguous space, we need to compensate our inode counter 7715 * appropriately. 7716 */ 7717 u64 num_needed = num_extents - dio_data->outstanding_extents; 7718 7719 spin_lock(&BTRFS_I(inode)->lock); 7720 BTRFS_I(inode)->outstanding_extents += num_needed; 7721 spin_unlock(&BTRFS_I(inode)->lock); 7722 } 7723 } 7724 7725 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock, 7726 struct buffer_head *bh_result, int create) 7727 { 7728 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7729 struct extent_map *em; 7730 struct extent_state *cached_state = NULL; 7731 struct btrfs_dio_data *dio_data = NULL; 7732 u64 start = iblock << inode->i_blkbits; 7733 u64 lockstart, lockend; 7734 u64 len = bh_result->b_size; 7735 int unlock_bits = EXTENT_LOCKED; 7736 int ret = 0; 7737 7738 if (create) 7739 unlock_bits |= EXTENT_DIRTY; 7740 else 7741 len = min_t(u64, len, fs_info->sectorsize); 7742 7743 lockstart = start; 7744 lockend = start + len - 1; 7745 7746 if (current->journal_info) { 7747 /* 7748 * Need to pull our outstanding extents and set journal_info to NULL so 7749 * that anything that needs to check if there's a transaction doesn't get 7750 * confused. 7751 */ 7752 dio_data = current->journal_info; 7753 current->journal_info = NULL; 7754 } 7755 7756 /* 7757 * If this errors out it's because we couldn't invalidate pagecache for 7758 * this range and we need to fallback to buffered. 7759 */ 7760 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, 7761 create)) { 7762 ret = -ENOTBLK; 7763 goto err; 7764 } 7765 7766 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0); 7767 if (IS_ERR(em)) { 7768 ret = PTR_ERR(em); 7769 goto unlock_err; 7770 } 7771 7772 /* 7773 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered 7774 * io. INLINE is special, and we could probably kludge it in here, but 7775 * it's still buffered so for safety lets just fall back to the generic 7776 * buffered path. 7777 * 7778 * For COMPRESSED we _have_ to read the entire extent in so we can 7779 * decompress it, so there will be buffering required no matter what we 7780 * do, so go ahead and fallback to buffered. 7781 * 7782 * We return -ENOTBLK because that's what makes DIO go ahead and go back 7783 * to buffered IO. Don't blame me, this is the price we pay for using 7784 * the generic code. 7785 */ 7786 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) || 7787 em->block_start == EXTENT_MAP_INLINE) { 7788 free_extent_map(em); 7789 ret = -ENOTBLK; 7790 goto unlock_err; 7791 } 7792 7793 /* Just a good old fashioned hole, return */ 7794 if (!create && (em->block_start == EXTENT_MAP_HOLE || 7795 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) { 7796 free_extent_map(em); 7797 goto unlock_err; 7798 } 7799 7800 /* 7801 * We don't allocate a new extent in the following cases 7802 * 7803 * 1) The inode is marked as NODATACOW. In this case we'll just use the 7804 * existing extent. 7805 * 2) The extent is marked as PREALLOC. We're good to go here and can 7806 * just use the extent. 7807 * 7808 */ 7809 if (!create) { 7810 len = min(len, em->len - (start - em->start)); 7811 lockstart = start + len; 7812 goto unlock; 7813 } 7814 7815 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) || 7816 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && 7817 em->block_start != EXTENT_MAP_HOLE)) { 7818 int type; 7819 u64 block_start, orig_start, orig_block_len, ram_bytes; 7820 7821 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7822 type = BTRFS_ORDERED_PREALLOC; 7823 else 7824 type = BTRFS_ORDERED_NOCOW; 7825 len = min(len, em->len - (start - em->start)); 7826 block_start = em->block_start + (start - em->start); 7827 7828 if (can_nocow_extent(inode, start, &len, &orig_start, 7829 &orig_block_len, &ram_bytes) == 1 && 7830 btrfs_inc_nocow_writers(fs_info, block_start)) { 7831 struct extent_map *em2; 7832 7833 em2 = btrfs_create_dio_extent(inode, start, len, 7834 orig_start, block_start, 7835 len, orig_block_len, 7836 ram_bytes, type); 7837 btrfs_dec_nocow_writers(fs_info, block_start); 7838 if (type == BTRFS_ORDERED_PREALLOC) { 7839 free_extent_map(em); 7840 em = em2; 7841 } 7842 if (em2 && IS_ERR(em2)) { 7843 ret = PTR_ERR(em2); 7844 goto unlock_err; 7845 } 7846 /* 7847 * For inode marked NODATACOW or extent marked PREALLOC, 7848 * use the existing or preallocated extent, so does not 7849 * need to adjust btrfs_space_info's bytes_may_use. 7850 */ 7851 btrfs_free_reserved_data_space_noquota(inode, 7852 start, len); 7853 goto unlock; 7854 } 7855 } 7856 7857 /* 7858 * this will cow the extent, reset the len in case we changed 7859 * it above 7860 */ 7861 len = bh_result->b_size; 7862 free_extent_map(em); 7863 em = btrfs_new_extent_direct(inode, start, len); 7864 if (IS_ERR(em)) { 7865 ret = PTR_ERR(em); 7866 goto unlock_err; 7867 } 7868 len = min(len, em->len - (start - em->start)); 7869 unlock: 7870 bh_result->b_blocknr = (em->block_start + (start - em->start)) >> 7871 inode->i_blkbits; 7872 bh_result->b_size = len; 7873 bh_result->b_bdev = em->bdev; 7874 set_buffer_mapped(bh_result); 7875 if (create) { 7876 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7877 set_buffer_new(bh_result); 7878 7879 /* 7880 * Need to update the i_size under the extent lock so buffered 7881 * readers will get the updated i_size when we unlock. 7882 */ 7883 if (!dio_data->overwrite && start + len > i_size_read(inode)) 7884 i_size_write(inode, start + len); 7885 7886 adjust_dio_outstanding_extents(inode, dio_data, len); 7887 WARN_ON(dio_data->reserve < len); 7888 dio_data->reserve -= len; 7889 dio_data->unsubmitted_oe_range_end = start + len; 7890 current->journal_info = dio_data; 7891 } 7892 7893 /* 7894 * In the case of write we need to clear and unlock the entire range, 7895 * in the case of read we need to unlock only the end area that we 7896 * aren't using if there is any left over space. 7897 */ 7898 if (lockstart < lockend) { 7899 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, 7900 lockend, unlock_bits, 1, 0, 7901 &cached_state, GFP_NOFS); 7902 } else { 7903 free_extent_state(cached_state); 7904 } 7905 7906 free_extent_map(em); 7907 7908 return 0; 7909 7910 unlock_err: 7911 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7912 unlock_bits, 1, 0, &cached_state, GFP_NOFS); 7913 err: 7914 if (dio_data) 7915 current->journal_info = dio_data; 7916 /* 7917 * Compensate the delalloc release we do in btrfs_direct_IO() when we 7918 * write less data then expected, so that we don't underflow our inode's 7919 * outstanding extents counter. 7920 */ 7921 if (create && dio_data) 7922 adjust_dio_outstanding_extents(inode, dio_data, len); 7923 7924 return ret; 7925 } 7926 7927 static inline int submit_dio_repair_bio(struct inode *inode, struct bio *bio, 7928 int mirror_num) 7929 { 7930 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7931 int ret; 7932 7933 BUG_ON(bio_op(bio) == REQ_OP_WRITE); 7934 7935 bio_get(bio); 7936 7937 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DIO_REPAIR); 7938 if (ret) 7939 goto err; 7940 7941 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0); 7942 err: 7943 bio_put(bio); 7944 return ret; 7945 } 7946 7947 static int btrfs_check_dio_repairable(struct inode *inode, 7948 struct bio *failed_bio, 7949 struct io_failure_record *failrec, 7950 int failed_mirror) 7951 { 7952 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7953 int num_copies; 7954 7955 num_copies = btrfs_num_copies(fs_info, failrec->logical, failrec->len); 7956 if (num_copies == 1) { 7957 /* 7958 * we only have a single copy of the data, so don't bother with 7959 * all the retry and error correction code that follows. no 7960 * matter what the error is, it is very likely to persist. 7961 */ 7962 btrfs_debug(fs_info, 7963 "Check DIO Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d", 7964 num_copies, failrec->this_mirror, failed_mirror); 7965 return 0; 7966 } 7967 7968 failrec->failed_mirror = failed_mirror; 7969 failrec->this_mirror++; 7970 if (failrec->this_mirror == failed_mirror) 7971 failrec->this_mirror++; 7972 7973 if (failrec->this_mirror > num_copies) { 7974 btrfs_debug(fs_info, 7975 "Check DIO Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d", 7976 num_copies, failrec->this_mirror, failed_mirror); 7977 return 0; 7978 } 7979 7980 return 1; 7981 } 7982 7983 static int dio_read_error(struct inode *inode, struct bio *failed_bio, 7984 struct page *page, unsigned int pgoff, 7985 u64 start, u64 end, int failed_mirror, 7986 bio_end_io_t *repair_endio, void *repair_arg) 7987 { 7988 struct io_failure_record *failrec; 7989 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 7990 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree; 7991 struct bio *bio; 7992 int isector; 7993 int read_mode = 0; 7994 int segs; 7995 int ret; 7996 7997 BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE); 7998 7999 ret = btrfs_get_io_failure_record(inode, start, end, &failrec); 8000 if (ret) 8001 return ret; 8002 8003 ret = btrfs_check_dio_repairable(inode, failed_bio, failrec, 8004 failed_mirror); 8005 if (!ret) { 8006 free_io_failure(failure_tree, io_tree, failrec); 8007 return -EIO; 8008 } 8009 8010 segs = bio_segments(failed_bio); 8011 if (segs > 1 || 8012 (failed_bio->bi_io_vec->bv_len > btrfs_inode_sectorsize(inode))) 8013 read_mode |= REQ_FAILFAST_DEV; 8014 8015 isector = start - btrfs_io_bio(failed_bio)->logical; 8016 isector >>= inode->i_sb->s_blocksize_bits; 8017 bio = btrfs_create_repair_bio(inode, failed_bio, failrec, page, 8018 pgoff, isector, repair_endio, repair_arg); 8019 bio_set_op_attrs(bio, REQ_OP_READ, read_mode); 8020 8021 btrfs_debug(BTRFS_I(inode)->root->fs_info, 8022 "Repair DIO Read Error: submitting new dio read[%#x] to this_mirror=%d, in_validation=%d\n", 8023 read_mode, failrec->this_mirror, failrec->in_validation); 8024 8025 ret = submit_dio_repair_bio(inode, bio, failrec->this_mirror); 8026 if (ret) { 8027 free_io_failure(failure_tree, io_tree, failrec); 8028 bio_put(bio); 8029 } 8030 8031 return ret; 8032 } 8033 8034 struct btrfs_retry_complete { 8035 struct completion done; 8036 struct inode *inode; 8037 u64 start; 8038 int uptodate; 8039 }; 8040 8041 static void btrfs_retry_endio_nocsum(struct bio *bio) 8042 { 8043 struct btrfs_retry_complete *done = bio->bi_private; 8044 struct inode *inode = done->inode; 8045 struct bio_vec *bvec; 8046 struct extent_io_tree *io_tree, *failure_tree; 8047 int i; 8048 8049 if (bio->bi_status) 8050 goto end; 8051 8052 ASSERT(bio->bi_vcnt == 1); 8053 io_tree = &BTRFS_I(inode)->io_tree; 8054 failure_tree = &BTRFS_I(inode)->io_failure_tree; 8055 ASSERT(bio->bi_io_vec->bv_len == btrfs_inode_sectorsize(inode)); 8056 8057 done->uptodate = 1; 8058 ASSERT(!bio_flagged(bio, BIO_CLONED)); 8059 bio_for_each_segment_all(bvec, bio, i) 8060 clean_io_failure(BTRFS_I(inode)->root->fs_info, failure_tree, 8061 io_tree, done->start, bvec->bv_page, 8062 btrfs_ino(BTRFS_I(inode)), 0); 8063 end: 8064 complete(&done->done); 8065 bio_put(bio); 8066 } 8067 8068 static int __btrfs_correct_data_nocsum(struct inode *inode, 8069 struct btrfs_io_bio *io_bio) 8070 { 8071 struct btrfs_fs_info *fs_info; 8072 struct bio_vec bvec; 8073 struct bvec_iter iter; 8074 struct btrfs_retry_complete done; 8075 u64 start; 8076 unsigned int pgoff; 8077 u32 sectorsize; 8078 int nr_sectors; 8079 int ret; 8080 int err = 0; 8081 8082 fs_info = BTRFS_I(inode)->root->fs_info; 8083 sectorsize = fs_info->sectorsize; 8084 8085 start = io_bio->logical; 8086 done.inode = inode; 8087 io_bio->bio.bi_iter = io_bio->iter; 8088 8089 bio_for_each_segment(bvec, &io_bio->bio, iter) { 8090 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len); 8091 pgoff = bvec.bv_offset; 8092 8093 next_block_or_try_again: 8094 done.uptodate = 0; 8095 done.start = start; 8096 init_completion(&done.done); 8097 8098 ret = dio_read_error(inode, &io_bio->bio, bvec.bv_page, 8099 pgoff, start, start + sectorsize - 1, 8100 io_bio->mirror_num, 8101 btrfs_retry_endio_nocsum, &done); 8102 if (ret) { 8103 err = ret; 8104 goto next; 8105 } 8106 8107 wait_for_completion(&done.done); 8108 8109 if (!done.uptodate) { 8110 /* We might have another mirror, so try again */ 8111 goto next_block_or_try_again; 8112 } 8113 8114 next: 8115 start += sectorsize; 8116 8117 nr_sectors--; 8118 if (nr_sectors) { 8119 pgoff += sectorsize; 8120 ASSERT(pgoff < PAGE_SIZE); 8121 goto next_block_or_try_again; 8122 } 8123 } 8124 8125 return err; 8126 } 8127 8128 static void btrfs_retry_endio(struct bio *bio) 8129 { 8130 struct btrfs_retry_complete *done = bio->bi_private; 8131 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 8132 struct extent_io_tree *io_tree, *failure_tree; 8133 struct inode *inode = done->inode; 8134 struct bio_vec *bvec; 8135 int uptodate; 8136 int ret; 8137 int i; 8138 8139 if (bio->bi_status) 8140 goto end; 8141 8142 uptodate = 1; 8143 8144 ASSERT(bio->bi_vcnt == 1); 8145 ASSERT(bio->bi_io_vec->bv_len == btrfs_inode_sectorsize(done->inode)); 8146 8147 io_tree = &BTRFS_I(inode)->io_tree; 8148 failure_tree = &BTRFS_I(inode)->io_failure_tree; 8149 8150 ASSERT(!bio_flagged(bio, BIO_CLONED)); 8151 bio_for_each_segment_all(bvec, bio, i) { 8152 ret = __readpage_endio_check(inode, io_bio, i, bvec->bv_page, 8153 bvec->bv_offset, done->start, 8154 bvec->bv_len); 8155 if (!ret) 8156 clean_io_failure(BTRFS_I(inode)->root->fs_info, 8157 failure_tree, io_tree, done->start, 8158 bvec->bv_page, 8159 btrfs_ino(BTRFS_I(inode)), 8160 bvec->bv_offset); 8161 else 8162 uptodate = 0; 8163 } 8164 8165 done->uptodate = uptodate; 8166 end: 8167 complete(&done->done); 8168 bio_put(bio); 8169 } 8170 8171 static blk_status_t __btrfs_subio_endio_read(struct inode *inode, 8172 struct btrfs_io_bio *io_bio, blk_status_t err) 8173 { 8174 struct btrfs_fs_info *fs_info; 8175 struct bio_vec bvec; 8176 struct bvec_iter iter; 8177 struct btrfs_retry_complete done; 8178 u64 start; 8179 u64 offset = 0; 8180 u32 sectorsize; 8181 int nr_sectors; 8182 unsigned int pgoff; 8183 int csum_pos; 8184 bool uptodate = (err == 0); 8185 int ret; 8186 8187 fs_info = BTRFS_I(inode)->root->fs_info; 8188 sectorsize = fs_info->sectorsize; 8189 8190 err = 0; 8191 start = io_bio->logical; 8192 done.inode = inode; 8193 io_bio->bio.bi_iter = io_bio->iter; 8194 8195 bio_for_each_segment(bvec, &io_bio->bio, iter) { 8196 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len); 8197 8198 pgoff = bvec.bv_offset; 8199 next_block: 8200 if (uptodate) { 8201 csum_pos = BTRFS_BYTES_TO_BLKS(fs_info, offset); 8202 ret = __readpage_endio_check(inode, io_bio, csum_pos, 8203 bvec.bv_page, pgoff, start, sectorsize); 8204 if (likely(!ret)) 8205 goto next; 8206 } 8207 try_again: 8208 done.uptodate = 0; 8209 done.start = start; 8210 init_completion(&done.done); 8211 8212 ret = dio_read_error(inode, &io_bio->bio, bvec.bv_page, 8213 pgoff, start, start + sectorsize - 1, 8214 io_bio->mirror_num, 8215 btrfs_retry_endio, &done); 8216 if (ret) { 8217 err = errno_to_blk_status(ret); 8218 goto next; 8219 } 8220 8221 wait_for_completion(&done.done); 8222 8223 if (!done.uptodate) { 8224 /* We might have another mirror, so try again */ 8225 goto try_again; 8226 } 8227 next: 8228 offset += sectorsize; 8229 start += sectorsize; 8230 8231 ASSERT(nr_sectors); 8232 8233 nr_sectors--; 8234 if (nr_sectors) { 8235 pgoff += sectorsize; 8236 ASSERT(pgoff < PAGE_SIZE); 8237 goto next_block; 8238 } 8239 } 8240 8241 return err; 8242 } 8243 8244 static blk_status_t btrfs_subio_endio_read(struct inode *inode, 8245 struct btrfs_io_bio *io_bio, blk_status_t err) 8246 { 8247 bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 8248 8249 if (skip_csum) { 8250 if (unlikely(err)) 8251 return __btrfs_correct_data_nocsum(inode, io_bio); 8252 else 8253 return 0; 8254 } else { 8255 return __btrfs_subio_endio_read(inode, io_bio, err); 8256 } 8257 } 8258 8259 static void btrfs_endio_direct_read(struct bio *bio) 8260 { 8261 struct btrfs_dio_private *dip = bio->bi_private; 8262 struct inode *inode = dip->inode; 8263 struct bio *dio_bio; 8264 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 8265 blk_status_t err = bio->bi_status; 8266 8267 if (dip->flags & BTRFS_DIO_ORIG_BIO_SUBMITTED) { 8268 err = btrfs_subio_endio_read(inode, io_bio, err); 8269 if (!err) 8270 bio->bi_status = 0; 8271 } 8272 8273 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset, 8274 dip->logical_offset + dip->bytes - 1); 8275 dio_bio = dip->dio_bio; 8276 8277 kfree(dip); 8278 8279 dio_bio->bi_status = bio->bi_status; 8280 dio_end_io(dio_bio); 8281 8282 if (io_bio->end_io) 8283 io_bio->end_io(io_bio, blk_status_to_errno(err)); 8284 bio_put(bio); 8285 } 8286 8287 static void __endio_write_update_ordered(struct inode *inode, 8288 const u64 offset, const u64 bytes, 8289 const bool uptodate) 8290 { 8291 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8292 struct btrfs_ordered_extent *ordered = NULL; 8293 struct btrfs_workqueue *wq; 8294 btrfs_work_func_t func; 8295 u64 ordered_offset = offset; 8296 u64 ordered_bytes = bytes; 8297 int ret; 8298 8299 if (btrfs_is_free_space_inode(BTRFS_I(inode))) { 8300 wq = fs_info->endio_freespace_worker; 8301 func = btrfs_freespace_write_helper; 8302 } else { 8303 wq = fs_info->endio_write_workers; 8304 func = btrfs_endio_write_helper; 8305 } 8306 8307 again: 8308 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered, 8309 &ordered_offset, 8310 ordered_bytes, 8311 uptodate); 8312 if (!ret) 8313 goto out_test; 8314 8315 btrfs_init_work(&ordered->work, func, finish_ordered_fn, NULL, NULL); 8316 btrfs_queue_work(wq, &ordered->work); 8317 out_test: 8318 /* 8319 * our bio might span multiple ordered extents. If we haven't 8320 * completed the accounting for the whole dio, go back and try again 8321 */ 8322 if (ordered_offset < offset + bytes) { 8323 ordered_bytes = offset + bytes - ordered_offset; 8324 ordered = NULL; 8325 goto again; 8326 } 8327 } 8328 8329 static void btrfs_endio_direct_write(struct bio *bio) 8330 { 8331 struct btrfs_dio_private *dip = bio->bi_private; 8332 struct bio *dio_bio = dip->dio_bio; 8333 8334 __endio_write_update_ordered(dip->inode, dip->logical_offset, 8335 dip->bytes, !bio->bi_status); 8336 8337 kfree(dip); 8338 8339 dio_bio->bi_status = bio->bi_status; 8340 dio_end_io(dio_bio); 8341 bio_put(bio); 8342 } 8343 8344 static blk_status_t __btrfs_submit_bio_start_direct_io(void *private_data, 8345 struct bio *bio, int mirror_num, 8346 unsigned long bio_flags, u64 offset) 8347 { 8348 struct inode *inode = private_data; 8349 blk_status_t ret; 8350 ret = btrfs_csum_one_bio(inode, bio, offset, 1); 8351 BUG_ON(ret); /* -ENOMEM */ 8352 return 0; 8353 } 8354 8355 static void btrfs_end_dio_bio(struct bio *bio) 8356 { 8357 struct btrfs_dio_private *dip = bio->bi_private; 8358 blk_status_t err = bio->bi_status; 8359 8360 if (err) 8361 btrfs_warn(BTRFS_I(dip->inode)->root->fs_info, 8362 "direct IO failed ino %llu rw %d,%u sector %#Lx len %u err no %d", 8363 btrfs_ino(BTRFS_I(dip->inode)), bio_op(bio), 8364 bio->bi_opf, 8365 (unsigned long long)bio->bi_iter.bi_sector, 8366 bio->bi_iter.bi_size, err); 8367 8368 if (dip->subio_endio) 8369 err = dip->subio_endio(dip->inode, btrfs_io_bio(bio), err); 8370 8371 if (err) { 8372 dip->errors = 1; 8373 8374 /* 8375 * before atomic variable goto zero, we must make sure 8376 * dip->errors is perceived to be set. 8377 */ 8378 smp_mb__before_atomic(); 8379 } 8380 8381 /* if there are more bios still pending for this dio, just exit */ 8382 if (!atomic_dec_and_test(&dip->pending_bios)) 8383 goto out; 8384 8385 if (dip->errors) { 8386 bio_io_error(dip->orig_bio); 8387 } else { 8388 dip->dio_bio->bi_status = 0; 8389 bio_endio(dip->orig_bio); 8390 } 8391 out: 8392 bio_put(bio); 8393 } 8394 8395 static inline blk_status_t btrfs_lookup_and_bind_dio_csum(struct inode *inode, 8396 struct btrfs_dio_private *dip, 8397 struct bio *bio, 8398 u64 file_offset) 8399 { 8400 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 8401 struct btrfs_io_bio *orig_io_bio = btrfs_io_bio(dip->orig_bio); 8402 blk_status_t ret; 8403 8404 /* 8405 * We load all the csum data we need when we submit 8406 * the first bio to reduce the csum tree search and 8407 * contention. 8408 */ 8409 if (dip->logical_offset == file_offset) { 8410 ret = btrfs_lookup_bio_sums_dio(inode, dip->orig_bio, 8411 file_offset); 8412 if (ret) 8413 return ret; 8414 } 8415 8416 if (bio == dip->orig_bio) 8417 return 0; 8418 8419 file_offset -= dip->logical_offset; 8420 file_offset >>= inode->i_sb->s_blocksize_bits; 8421 io_bio->csum = (u8 *)(((u32 *)orig_io_bio->csum) + file_offset); 8422 8423 return 0; 8424 } 8425 8426 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode, 8427 u64 file_offset, int skip_sum, 8428 int async_submit) 8429 { 8430 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8431 struct btrfs_dio_private *dip = bio->bi_private; 8432 bool write = bio_op(bio) == REQ_OP_WRITE; 8433 blk_status_t ret; 8434 8435 if (async_submit) 8436 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers); 8437 8438 bio_get(bio); 8439 8440 if (!write) { 8441 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA); 8442 if (ret) 8443 goto err; 8444 } 8445 8446 if (skip_sum) 8447 goto map; 8448 8449 if (write && async_submit) { 8450 ret = btrfs_wq_submit_bio(fs_info, bio, 0, 0, 8451 file_offset, inode, 8452 __btrfs_submit_bio_start_direct_io, 8453 __btrfs_submit_bio_done); 8454 goto err; 8455 } else if (write) { 8456 /* 8457 * If we aren't doing async submit, calculate the csum of the 8458 * bio now. 8459 */ 8460 ret = btrfs_csum_one_bio(inode, bio, file_offset, 1); 8461 if (ret) 8462 goto err; 8463 } else { 8464 ret = btrfs_lookup_and_bind_dio_csum(inode, dip, bio, 8465 file_offset); 8466 if (ret) 8467 goto err; 8468 } 8469 map: 8470 ret = btrfs_map_bio(fs_info, bio, 0, async_submit); 8471 err: 8472 bio_put(bio); 8473 return ret; 8474 } 8475 8476 static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip, 8477 int skip_sum) 8478 { 8479 struct inode *inode = dip->inode; 8480 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8481 struct bio *bio; 8482 struct bio *orig_bio = dip->orig_bio; 8483 u64 start_sector = orig_bio->bi_iter.bi_sector; 8484 u64 file_offset = dip->logical_offset; 8485 u64 map_length; 8486 int async_submit = 0; 8487 u64 submit_len; 8488 int clone_offset = 0; 8489 int clone_len; 8490 int ret; 8491 8492 map_length = orig_bio->bi_iter.bi_size; 8493 submit_len = map_length; 8494 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9, 8495 &map_length, NULL, 0); 8496 if (ret) 8497 return -EIO; 8498 8499 if (map_length >= submit_len) { 8500 bio = orig_bio; 8501 dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED; 8502 goto submit; 8503 } 8504 8505 /* async crcs make it difficult to collect full stripe writes. */ 8506 if (btrfs_data_alloc_profile(fs_info) & BTRFS_BLOCK_GROUP_RAID56_MASK) 8507 async_submit = 0; 8508 else 8509 async_submit = 1; 8510 8511 /* bio split */ 8512 ASSERT(map_length <= INT_MAX); 8513 atomic_inc(&dip->pending_bios); 8514 do { 8515 clone_len = min_t(int, submit_len, map_length); 8516 8517 /* 8518 * This will never fail as it's passing GPF_NOFS and 8519 * the allocation is backed by btrfs_bioset. 8520 */ 8521 bio = btrfs_bio_clone_partial(orig_bio, clone_offset, 8522 clone_len); 8523 bio->bi_private = dip; 8524 bio->bi_end_io = btrfs_end_dio_bio; 8525 btrfs_io_bio(bio)->logical = file_offset; 8526 8527 ASSERT(submit_len >= clone_len); 8528 submit_len -= clone_len; 8529 if (submit_len == 0) 8530 break; 8531 8532 /* 8533 * Increase the count before we submit the bio so we know 8534 * the end IO handler won't happen before we increase the 8535 * count. Otherwise, the dip might get freed before we're 8536 * done setting it up. 8537 */ 8538 atomic_inc(&dip->pending_bios); 8539 8540 ret = __btrfs_submit_dio_bio(bio, inode, file_offset, skip_sum, 8541 async_submit); 8542 if (ret) { 8543 bio_put(bio); 8544 atomic_dec(&dip->pending_bios); 8545 goto out_err; 8546 } 8547 8548 clone_offset += clone_len; 8549 start_sector += clone_len >> 9; 8550 file_offset += clone_len; 8551 8552 map_length = submit_len; 8553 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), 8554 start_sector << 9, &map_length, NULL, 0); 8555 if (ret) 8556 goto out_err; 8557 } while (submit_len > 0); 8558 8559 submit: 8560 ret = __btrfs_submit_dio_bio(bio, inode, file_offset, skip_sum, 8561 async_submit); 8562 if (!ret) 8563 return 0; 8564 8565 bio_put(bio); 8566 out_err: 8567 dip->errors = 1; 8568 /* 8569 * before atomic variable goto zero, we must 8570 * make sure dip->errors is perceived to be set. 8571 */ 8572 smp_mb__before_atomic(); 8573 if (atomic_dec_and_test(&dip->pending_bios)) 8574 bio_io_error(dip->orig_bio); 8575 8576 /* bio_end_io() will handle error, so we needn't return it */ 8577 return 0; 8578 } 8579 8580 static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode, 8581 loff_t file_offset) 8582 { 8583 struct btrfs_dio_private *dip = NULL; 8584 struct bio *bio = NULL; 8585 struct btrfs_io_bio *io_bio; 8586 int skip_sum; 8587 bool write = (bio_op(dio_bio) == REQ_OP_WRITE); 8588 int ret = 0; 8589 8590 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 8591 8592 bio = btrfs_bio_clone(dio_bio); 8593 8594 dip = kzalloc(sizeof(*dip), GFP_NOFS); 8595 if (!dip) { 8596 ret = -ENOMEM; 8597 goto free_ordered; 8598 } 8599 8600 dip->private = dio_bio->bi_private; 8601 dip->inode = inode; 8602 dip->logical_offset = file_offset; 8603 dip->bytes = dio_bio->bi_iter.bi_size; 8604 dip->disk_bytenr = (u64)dio_bio->bi_iter.bi_sector << 9; 8605 bio->bi_private = dip; 8606 dip->orig_bio = bio; 8607 dip->dio_bio = dio_bio; 8608 atomic_set(&dip->pending_bios, 0); 8609 io_bio = btrfs_io_bio(bio); 8610 io_bio->logical = file_offset; 8611 8612 if (write) { 8613 bio->bi_end_io = btrfs_endio_direct_write; 8614 } else { 8615 bio->bi_end_io = btrfs_endio_direct_read; 8616 dip->subio_endio = btrfs_subio_endio_read; 8617 } 8618 8619 /* 8620 * Reset the range for unsubmitted ordered extents (to a 0 length range) 8621 * even if we fail to submit a bio, because in such case we do the 8622 * corresponding error handling below and it must not be done a second 8623 * time by btrfs_direct_IO(). 8624 */ 8625 if (write) { 8626 struct btrfs_dio_data *dio_data = current->journal_info; 8627 8628 dio_data->unsubmitted_oe_range_end = dip->logical_offset + 8629 dip->bytes; 8630 dio_data->unsubmitted_oe_range_start = 8631 dio_data->unsubmitted_oe_range_end; 8632 } 8633 8634 ret = btrfs_submit_direct_hook(dip, skip_sum); 8635 if (!ret) 8636 return; 8637 8638 if (io_bio->end_io) 8639 io_bio->end_io(io_bio, ret); 8640 8641 free_ordered: 8642 /* 8643 * If we arrived here it means either we failed to submit the dip 8644 * or we either failed to clone the dio_bio or failed to allocate the 8645 * dip. If we cloned the dio_bio and allocated the dip, we can just 8646 * call bio_endio against our io_bio so that we get proper resource 8647 * cleanup if we fail to submit the dip, otherwise, we must do the 8648 * same as btrfs_endio_direct_[write|read] because we can't call these 8649 * callbacks - they require an allocated dip and a clone of dio_bio. 8650 */ 8651 if (bio && dip) { 8652 bio_io_error(bio); 8653 /* 8654 * The end io callbacks free our dip, do the final put on bio 8655 * and all the cleanup and final put for dio_bio (through 8656 * dio_end_io()). 8657 */ 8658 dip = NULL; 8659 bio = NULL; 8660 } else { 8661 if (write) 8662 __endio_write_update_ordered(inode, 8663 file_offset, 8664 dio_bio->bi_iter.bi_size, 8665 false); 8666 else 8667 unlock_extent(&BTRFS_I(inode)->io_tree, file_offset, 8668 file_offset + dio_bio->bi_iter.bi_size - 1); 8669 8670 dio_bio->bi_status = BLK_STS_IOERR; 8671 /* 8672 * Releases and cleans up our dio_bio, no need to bio_put() 8673 * nor bio_endio()/bio_io_error() against dio_bio. 8674 */ 8675 dio_end_io(dio_bio); 8676 } 8677 if (bio) 8678 bio_put(bio); 8679 kfree(dip); 8680 } 8681 8682 static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info, 8683 struct kiocb *iocb, 8684 const struct iov_iter *iter, loff_t offset) 8685 { 8686 int seg; 8687 int i; 8688 unsigned int blocksize_mask = fs_info->sectorsize - 1; 8689 ssize_t retval = -EINVAL; 8690 8691 if (offset & blocksize_mask) 8692 goto out; 8693 8694 if (iov_iter_alignment(iter) & blocksize_mask) 8695 goto out; 8696 8697 /* If this is a write we don't need to check anymore */ 8698 if (iov_iter_rw(iter) != READ || !iter_is_iovec(iter)) 8699 return 0; 8700 /* 8701 * Check to make sure we don't have duplicate iov_base's in this 8702 * iovec, if so return EINVAL, otherwise we'll get csum errors 8703 * when reading back. 8704 */ 8705 for (seg = 0; seg < iter->nr_segs; seg++) { 8706 for (i = seg + 1; i < iter->nr_segs; i++) { 8707 if (iter->iov[seg].iov_base == iter->iov[i].iov_base) 8708 goto out; 8709 } 8710 } 8711 retval = 0; 8712 out: 8713 return retval; 8714 } 8715 8716 static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) 8717 { 8718 struct file *file = iocb->ki_filp; 8719 struct inode *inode = file->f_mapping->host; 8720 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8721 struct btrfs_dio_data dio_data = { 0 }; 8722 struct extent_changeset *data_reserved = NULL; 8723 loff_t offset = iocb->ki_pos; 8724 size_t count = 0; 8725 int flags = 0; 8726 bool wakeup = true; 8727 bool relock = false; 8728 ssize_t ret; 8729 8730 if (check_direct_IO(fs_info, iocb, iter, offset)) 8731 return 0; 8732 8733 inode_dio_begin(inode); 8734 smp_mb__after_atomic(); 8735 8736 /* 8737 * The generic stuff only does filemap_write_and_wait_range, which 8738 * isn't enough if we've written compressed pages to this area, so 8739 * we need to flush the dirty pages again to make absolutely sure 8740 * that any outstanding dirty pages are on disk. 8741 */ 8742 count = iov_iter_count(iter); 8743 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 8744 &BTRFS_I(inode)->runtime_flags)) 8745 filemap_fdatawrite_range(inode->i_mapping, offset, 8746 offset + count - 1); 8747 8748 if (iov_iter_rw(iter) == WRITE) { 8749 /* 8750 * If the write DIO is beyond the EOF, we need update 8751 * the isize, but it is protected by i_mutex. So we can 8752 * not unlock the i_mutex at this case. 8753 */ 8754 if (offset + count <= inode->i_size) { 8755 dio_data.overwrite = 1; 8756 inode_unlock(inode); 8757 relock = true; 8758 } else if (iocb->ki_flags & IOCB_NOWAIT) { 8759 ret = -EAGAIN; 8760 goto out; 8761 } 8762 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, 8763 offset, count); 8764 if (ret) 8765 goto out; 8766 dio_data.outstanding_extents = count_max_extents(count); 8767 8768 /* 8769 * We need to know how many extents we reserved so that we can 8770 * do the accounting properly if we go over the number we 8771 * originally calculated. Abuse current->journal_info for this. 8772 */ 8773 dio_data.reserve = round_up(count, 8774 fs_info->sectorsize); 8775 dio_data.unsubmitted_oe_range_start = (u64)offset; 8776 dio_data.unsubmitted_oe_range_end = (u64)offset; 8777 current->journal_info = &dio_data; 8778 down_read(&BTRFS_I(inode)->dio_sem); 8779 } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK, 8780 &BTRFS_I(inode)->runtime_flags)) { 8781 inode_dio_end(inode); 8782 flags = DIO_LOCKING | DIO_SKIP_HOLES; 8783 wakeup = false; 8784 } 8785 8786 ret = __blockdev_direct_IO(iocb, inode, 8787 fs_info->fs_devices->latest_bdev, 8788 iter, btrfs_get_blocks_direct, NULL, 8789 btrfs_submit_direct, flags); 8790 if (iov_iter_rw(iter) == WRITE) { 8791 up_read(&BTRFS_I(inode)->dio_sem); 8792 current->journal_info = NULL; 8793 if (ret < 0 && ret != -EIOCBQUEUED) { 8794 if (dio_data.reserve) 8795 btrfs_delalloc_release_space(inode, data_reserved, 8796 offset, dio_data.reserve); 8797 /* 8798 * On error we might have left some ordered extents 8799 * without submitting corresponding bios for them, so 8800 * cleanup them up to avoid other tasks getting them 8801 * and waiting for them to complete forever. 8802 */ 8803 if (dio_data.unsubmitted_oe_range_start < 8804 dio_data.unsubmitted_oe_range_end) 8805 __endio_write_update_ordered(inode, 8806 dio_data.unsubmitted_oe_range_start, 8807 dio_data.unsubmitted_oe_range_end - 8808 dio_data.unsubmitted_oe_range_start, 8809 false); 8810 } else if (ret >= 0 && (size_t)ret < count) 8811 btrfs_delalloc_release_space(inode, data_reserved, 8812 offset, count - (size_t)ret); 8813 } 8814 out: 8815 if (wakeup) 8816 inode_dio_end(inode); 8817 if (relock) 8818 inode_lock(inode); 8819 8820 extent_changeset_free(data_reserved); 8821 return ret; 8822 } 8823 8824 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC) 8825 8826 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, 8827 __u64 start, __u64 len) 8828 { 8829 int ret; 8830 8831 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS); 8832 if (ret) 8833 return ret; 8834 8835 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap); 8836 } 8837 8838 int btrfs_readpage(struct file *file, struct page *page) 8839 { 8840 struct extent_io_tree *tree; 8841 tree = &BTRFS_I(page->mapping->host)->io_tree; 8842 return extent_read_full_page(tree, page, btrfs_get_extent, 0); 8843 } 8844 8845 static int btrfs_writepage(struct page *page, struct writeback_control *wbc) 8846 { 8847 struct extent_io_tree *tree; 8848 struct inode *inode = page->mapping->host; 8849 int ret; 8850 8851 if (current->flags & PF_MEMALLOC) { 8852 redirty_page_for_writepage(wbc, page); 8853 unlock_page(page); 8854 return 0; 8855 } 8856 8857 /* 8858 * If we are under memory pressure we will call this directly from the 8859 * VM, we need to make sure we have the inode referenced for the ordered 8860 * extent. If not just return like we didn't do anything. 8861 */ 8862 if (!igrab(inode)) { 8863 redirty_page_for_writepage(wbc, page); 8864 return AOP_WRITEPAGE_ACTIVATE; 8865 } 8866 tree = &BTRFS_I(page->mapping->host)->io_tree; 8867 ret = extent_write_full_page(tree, page, btrfs_get_extent, wbc); 8868 btrfs_add_delayed_iput(inode); 8869 return ret; 8870 } 8871 8872 static int btrfs_writepages(struct address_space *mapping, 8873 struct writeback_control *wbc) 8874 { 8875 struct extent_io_tree *tree; 8876 8877 tree = &BTRFS_I(mapping->host)->io_tree; 8878 return extent_writepages(tree, mapping, btrfs_get_extent, wbc); 8879 } 8880 8881 static int 8882 btrfs_readpages(struct file *file, struct address_space *mapping, 8883 struct list_head *pages, unsigned nr_pages) 8884 { 8885 struct extent_io_tree *tree; 8886 tree = &BTRFS_I(mapping->host)->io_tree; 8887 return extent_readpages(tree, mapping, pages, nr_pages, 8888 btrfs_get_extent); 8889 } 8890 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) 8891 { 8892 struct extent_io_tree *tree; 8893 struct extent_map_tree *map; 8894 int ret; 8895 8896 tree = &BTRFS_I(page->mapping->host)->io_tree; 8897 map = &BTRFS_I(page->mapping->host)->extent_tree; 8898 ret = try_release_extent_mapping(map, tree, page, gfp_flags); 8899 if (ret == 1) { 8900 ClearPagePrivate(page); 8901 set_page_private(page, 0); 8902 put_page(page); 8903 } 8904 return ret; 8905 } 8906 8907 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) 8908 { 8909 if (PageWriteback(page) || PageDirty(page)) 8910 return 0; 8911 return __btrfs_releasepage(page, gfp_flags); 8912 } 8913 8914 static void btrfs_invalidatepage(struct page *page, unsigned int offset, 8915 unsigned int length) 8916 { 8917 struct inode *inode = page->mapping->host; 8918 struct extent_io_tree *tree; 8919 struct btrfs_ordered_extent *ordered; 8920 struct extent_state *cached_state = NULL; 8921 u64 page_start = page_offset(page); 8922 u64 page_end = page_start + PAGE_SIZE - 1; 8923 u64 start; 8924 u64 end; 8925 int inode_evicting = inode->i_state & I_FREEING; 8926 8927 /* 8928 * we have the page locked, so new writeback can't start, 8929 * and the dirty bit won't be cleared while we are here. 8930 * 8931 * Wait for IO on this page so that we can safely clear 8932 * the PagePrivate2 bit and do ordered accounting 8933 */ 8934 wait_on_page_writeback(page); 8935 8936 tree = &BTRFS_I(inode)->io_tree; 8937 if (offset) { 8938 btrfs_releasepage(page, GFP_NOFS); 8939 return; 8940 } 8941 8942 if (!inode_evicting) 8943 lock_extent_bits(tree, page_start, page_end, &cached_state); 8944 again: 8945 start = page_start; 8946 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start, 8947 page_end - start + 1); 8948 if (ordered) { 8949 end = min(page_end, ordered->file_offset + ordered->len - 1); 8950 /* 8951 * IO on this page will never be started, so we need 8952 * to account for any ordered extents now 8953 */ 8954 if (!inode_evicting) 8955 clear_extent_bit(tree, start, end, 8956 EXTENT_DIRTY | EXTENT_DELALLOC | 8957 EXTENT_DELALLOC_NEW | 8958 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING | 8959 EXTENT_DEFRAG, 1, 0, &cached_state, 8960 GFP_NOFS); 8961 /* 8962 * whoever cleared the private bit is responsible 8963 * for the finish_ordered_io 8964 */ 8965 if (TestClearPagePrivate2(page)) { 8966 struct btrfs_ordered_inode_tree *tree; 8967 u64 new_len; 8968 8969 tree = &BTRFS_I(inode)->ordered_tree; 8970 8971 spin_lock_irq(&tree->lock); 8972 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); 8973 new_len = start - ordered->file_offset; 8974 if (new_len < ordered->truncated_len) 8975 ordered->truncated_len = new_len; 8976 spin_unlock_irq(&tree->lock); 8977 8978 if (btrfs_dec_test_ordered_pending(inode, &ordered, 8979 start, 8980 end - start + 1, 1)) 8981 btrfs_finish_ordered_io(ordered); 8982 } 8983 btrfs_put_ordered_extent(ordered); 8984 if (!inode_evicting) { 8985 cached_state = NULL; 8986 lock_extent_bits(tree, start, end, 8987 &cached_state); 8988 } 8989 8990 start = end + 1; 8991 if (start < page_end) 8992 goto again; 8993 } 8994 8995 /* 8996 * Qgroup reserved space handler 8997 * Page here will be either 8998 * 1) Already written to disk 8999 * In this case, its reserved space is released from data rsv map 9000 * and will be freed by delayed_ref handler finally. 9001 * So even we call qgroup_free_data(), it won't decrease reserved 9002 * space. 9003 * 2) Not written to disk 9004 * This means the reserved space should be freed here. However, 9005 * if a truncate invalidates the page (by clearing PageDirty) 9006 * and the page is accounted for while allocating extent 9007 * in btrfs_check_data_free_space() we let delayed_ref to 9008 * free the entire extent. 9009 */ 9010 if (PageDirty(page)) 9011 btrfs_qgroup_free_data(inode, NULL, page_start, PAGE_SIZE); 9012 if (!inode_evicting) { 9013 clear_extent_bit(tree, page_start, page_end, 9014 EXTENT_LOCKED | EXTENT_DIRTY | 9015 EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | 9016 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1, 9017 &cached_state, GFP_NOFS); 9018 9019 __btrfs_releasepage(page, GFP_NOFS); 9020 } 9021 9022 ClearPageChecked(page); 9023 if (PagePrivate(page)) { 9024 ClearPagePrivate(page); 9025 set_page_private(page, 0); 9026 put_page(page); 9027 } 9028 } 9029 9030 /* 9031 * btrfs_page_mkwrite() is not allowed to change the file size as it gets 9032 * called from a page fault handler when a page is first dirtied. Hence we must 9033 * be careful to check for EOF conditions here. We set the page up correctly 9034 * for a written page which means we get ENOSPC checking when writing into 9035 * holes and correct delalloc and unwritten extent mapping on filesystems that 9036 * support these features. 9037 * 9038 * We are not allowed to take the i_mutex here so we have to play games to 9039 * protect against truncate races as the page could now be beyond EOF. Because 9040 * vmtruncate() writes the inode size before removing pages, once we have the 9041 * page lock we can determine safely if the page is beyond EOF. If it is not 9042 * beyond EOF, then the page is guaranteed safe against truncation until we 9043 * unlock the page. 9044 */ 9045 int btrfs_page_mkwrite(struct vm_fault *vmf) 9046 { 9047 struct page *page = vmf->page; 9048 struct inode *inode = file_inode(vmf->vma->vm_file); 9049 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 9050 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 9051 struct btrfs_ordered_extent *ordered; 9052 struct extent_state *cached_state = NULL; 9053 struct extent_changeset *data_reserved = NULL; 9054 char *kaddr; 9055 unsigned long zero_start; 9056 loff_t size; 9057 int ret; 9058 int reserved = 0; 9059 u64 reserved_space; 9060 u64 page_start; 9061 u64 page_end; 9062 u64 end; 9063 9064 reserved_space = PAGE_SIZE; 9065 9066 sb_start_pagefault(inode->i_sb); 9067 page_start = page_offset(page); 9068 page_end = page_start + PAGE_SIZE - 1; 9069 end = page_end; 9070 9071 /* 9072 * Reserving delalloc space after obtaining the page lock can lead to 9073 * deadlock. For example, if a dirty page is locked by this function 9074 * and the call to btrfs_delalloc_reserve_space() ends up triggering 9075 * dirty page write out, then the btrfs_writepage() function could 9076 * end up waiting indefinitely to get a lock on the page currently 9077 * being processed by btrfs_page_mkwrite() function. 9078 */ 9079 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, 9080 reserved_space); 9081 if (!ret) { 9082 ret = file_update_time(vmf->vma->vm_file); 9083 reserved = 1; 9084 } 9085 if (ret) { 9086 if (ret == -ENOMEM) 9087 ret = VM_FAULT_OOM; 9088 else /* -ENOSPC, -EIO, etc */ 9089 ret = VM_FAULT_SIGBUS; 9090 if (reserved) 9091 goto out; 9092 goto out_noreserve; 9093 } 9094 9095 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ 9096 again: 9097 lock_page(page); 9098 size = i_size_read(inode); 9099 9100 if ((page->mapping != inode->i_mapping) || 9101 (page_start >= size)) { 9102 /* page got truncated out from underneath us */ 9103 goto out_unlock; 9104 } 9105 wait_on_page_writeback(page); 9106 9107 lock_extent_bits(io_tree, page_start, page_end, &cached_state); 9108 set_page_extent_mapped(page); 9109 9110 /* 9111 * we can't set the delalloc bits if there are pending ordered 9112 * extents. Drop our locks and wait for them to finish 9113 */ 9114 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start, 9115 PAGE_SIZE); 9116 if (ordered) { 9117 unlock_extent_cached(io_tree, page_start, page_end, 9118 &cached_state, GFP_NOFS); 9119 unlock_page(page); 9120 btrfs_start_ordered_extent(inode, ordered, 1); 9121 btrfs_put_ordered_extent(ordered); 9122 goto again; 9123 } 9124 9125 if (page->index == ((size - 1) >> PAGE_SHIFT)) { 9126 reserved_space = round_up(size - page_start, 9127 fs_info->sectorsize); 9128 if (reserved_space < PAGE_SIZE) { 9129 end = page_start + reserved_space - 1; 9130 spin_lock(&BTRFS_I(inode)->lock); 9131 BTRFS_I(inode)->outstanding_extents++; 9132 spin_unlock(&BTRFS_I(inode)->lock); 9133 btrfs_delalloc_release_space(inode, data_reserved, 9134 page_start, PAGE_SIZE - reserved_space); 9135 } 9136 } 9137 9138 /* 9139 * page_mkwrite gets called when the page is firstly dirtied after it's 9140 * faulted in, but write(2) could also dirty a page and set delalloc 9141 * bits, thus in this case for space account reason, we still need to 9142 * clear any delalloc bits within this page range since we have to 9143 * reserve data&meta space before lock_page() (see above comments). 9144 */ 9145 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, end, 9146 EXTENT_DIRTY | EXTENT_DELALLOC | 9147 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 9148 0, 0, &cached_state, GFP_NOFS); 9149 9150 ret = btrfs_set_extent_delalloc(inode, page_start, end, 9151 &cached_state, 0); 9152 if (ret) { 9153 unlock_extent_cached(io_tree, page_start, page_end, 9154 &cached_state, GFP_NOFS); 9155 ret = VM_FAULT_SIGBUS; 9156 goto out_unlock; 9157 } 9158 ret = 0; 9159 9160 /* page is wholly or partially inside EOF */ 9161 if (page_start + PAGE_SIZE > size) 9162 zero_start = size & ~PAGE_MASK; 9163 else 9164 zero_start = PAGE_SIZE; 9165 9166 if (zero_start != PAGE_SIZE) { 9167 kaddr = kmap(page); 9168 memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start); 9169 flush_dcache_page(page); 9170 kunmap(page); 9171 } 9172 ClearPageChecked(page); 9173 set_page_dirty(page); 9174 SetPageUptodate(page); 9175 9176 BTRFS_I(inode)->last_trans = fs_info->generation; 9177 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid; 9178 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit; 9179 9180 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS); 9181 9182 out_unlock: 9183 if (!ret) { 9184 sb_end_pagefault(inode->i_sb); 9185 extent_changeset_free(data_reserved); 9186 return VM_FAULT_LOCKED; 9187 } 9188 unlock_page(page); 9189 out: 9190 btrfs_delalloc_release_space(inode, data_reserved, page_start, 9191 reserved_space); 9192 out_noreserve: 9193 sb_end_pagefault(inode->i_sb); 9194 extent_changeset_free(data_reserved); 9195 return ret; 9196 } 9197 9198 static int btrfs_truncate(struct inode *inode) 9199 { 9200 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 9201 struct btrfs_root *root = BTRFS_I(inode)->root; 9202 struct btrfs_block_rsv *rsv; 9203 int ret = 0; 9204 int err = 0; 9205 struct btrfs_trans_handle *trans; 9206 u64 mask = fs_info->sectorsize - 1; 9207 u64 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1); 9208 9209 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask), 9210 (u64)-1); 9211 if (ret) 9212 return ret; 9213 9214 /* 9215 * Yes ladies and gentlemen, this is indeed ugly. The fact is we have 9216 * 3 things going on here 9217 * 9218 * 1) We need to reserve space for our orphan item and the space to 9219 * delete our orphan item. Lord knows we don't want to have a dangling 9220 * orphan item because we didn't reserve space to remove it. 9221 * 9222 * 2) We need to reserve space to update our inode. 9223 * 9224 * 3) We need to have something to cache all the space that is going to 9225 * be free'd up by the truncate operation, but also have some slack 9226 * space reserved in case it uses space during the truncate (thank you 9227 * very much snapshotting). 9228 * 9229 * And we need these to all be separate. The fact is we can use a lot of 9230 * space doing the truncate, and we have no earthly idea how much space 9231 * we will use, so we need the truncate reservation to be separate so it 9232 * doesn't end up using space reserved for updating the inode or 9233 * removing the orphan item. We also need to be able to stop the 9234 * transaction and start a new one, which means we need to be able to 9235 * update the inode several times, and we have no idea of knowing how 9236 * many times that will be, so we can't just reserve 1 item for the 9237 * entirety of the operation, so that has to be done separately as well. 9238 * Then there is the orphan item, which does indeed need to be held on 9239 * to for the whole operation, and we need nobody to touch this reserved 9240 * space except the orphan code. 9241 * 9242 * So that leaves us with 9243 * 9244 * 1) root->orphan_block_rsv - for the orphan deletion. 9245 * 2) rsv - for the truncate reservation, which we will steal from the 9246 * transaction reservation. 9247 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for 9248 * updating the inode. 9249 */ 9250 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); 9251 if (!rsv) 9252 return -ENOMEM; 9253 rsv->size = min_size; 9254 rsv->failfast = 1; 9255 9256 /* 9257 * 1 for the truncate slack space 9258 * 1 for updating the inode. 9259 */ 9260 trans = btrfs_start_transaction(root, 2); 9261 if (IS_ERR(trans)) { 9262 err = PTR_ERR(trans); 9263 goto out; 9264 } 9265 9266 /* Migrate the slack space for the truncate to our reserve */ 9267 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv, 9268 min_size, 0); 9269 BUG_ON(ret); 9270 9271 /* 9272 * So if we truncate and then write and fsync we normally would just 9273 * write the extents that changed, which is a problem if we need to 9274 * first truncate that entire inode. So set this flag so we write out 9275 * all of the extents in the inode to the sync log so we're completely 9276 * safe. 9277 */ 9278 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 9279 trans->block_rsv = rsv; 9280 9281 while (1) { 9282 ret = btrfs_truncate_inode_items(trans, root, inode, 9283 inode->i_size, 9284 BTRFS_EXTENT_DATA_KEY); 9285 if (ret != -ENOSPC && ret != -EAGAIN) { 9286 err = ret; 9287 break; 9288 } 9289 9290 trans->block_rsv = &fs_info->trans_block_rsv; 9291 ret = btrfs_update_inode(trans, root, inode); 9292 if (ret) { 9293 err = ret; 9294 break; 9295 } 9296 9297 btrfs_end_transaction(trans); 9298 btrfs_btree_balance_dirty(fs_info); 9299 9300 trans = btrfs_start_transaction(root, 2); 9301 if (IS_ERR(trans)) { 9302 ret = err = PTR_ERR(trans); 9303 trans = NULL; 9304 break; 9305 } 9306 9307 btrfs_block_rsv_release(fs_info, rsv, -1); 9308 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, 9309 rsv, min_size, 0); 9310 BUG_ON(ret); /* shouldn't happen */ 9311 trans->block_rsv = rsv; 9312 } 9313 9314 if (ret == 0 && inode->i_nlink > 0) { 9315 trans->block_rsv = root->orphan_block_rsv; 9316 ret = btrfs_orphan_del(trans, BTRFS_I(inode)); 9317 if (ret) 9318 err = ret; 9319 } 9320 9321 if (trans) { 9322 trans->block_rsv = &fs_info->trans_block_rsv; 9323 ret = btrfs_update_inode(trans, root, inode); 9324 if (ret && !err) 9325 err = ret; 9326 9327 ret = btrfs_end_transaction(trans); 9328 btrfs_btree_balance_dirty(fs_info); 9329 } 9330 out: 9331 btrfs_free_block_rsv(fs_info, rsv); 9332 9333 if (ret && !err) 9334 err = ret; 9335 9336 return err; 9337 } 9338 9339 /* 9340 * create a new subvolume directory/inode (helper for the ioctl). 9341 */ 9342 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, 9343 struct btrfs_root *new_root, 9344 struct btrfs_root *parent_root, 9345 u64 new_dirid) 9346 { 9347 struct inode *inode; 9348 int err; 9349 u64 index = 0; 9350 9351 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, 9352 new_dirid, new_dirid, 9353 S_IFDIR | (~current_umask() & S_IRWXUGO), 9354 &index); 9355 if (IS_ERR(inode)) 9356 return PTR_ERR(inode); 9357 inode->i_op = &btrfs_dir_inode_operations; 9358 inode->i_fop = &btrfs_dir_file_operations; 9359 9360 set_nlink(inode, 1); 9361 btrfs_i_size_write(BTRFS_I(inode), 0); 9362 unlock_new_inode(inode); 9363 9364 err = btrfs_subvol_inherit_props(trans, new_root, parent_root); 9365 if (err) 9366 btrfs_err(new_root->fs_info, 9367 "error inheriting subvolume %llu properties: %d", 9368 new_root->root_key.objectid, err); 9369 9370 err = btrfs_update_inode(trans, new_root, inode); 9371 9372 iput(inode); 9373 return err; 9374 } 9375 9376 struct inode *btrfs_alloc_inode(struct super_block *sb) 9377 { 9378 struct btrfs_inode *ei; 9379 struct inode *inode; 9380 9381 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS); 9382 if (!ei) 9383 return NULL; 9384 9385 ei->root = NULL; 9386 ei->generation = 0; 9387 ei->last_trans = 0; 9388 ei->last_sub_trans = 0; 9389 ei->logged_trans = 0; 9390 ei->delalloc_bytes = 0; 9391 ei->new_delalloc_bytes = 0; 9392 ei->defrag_bytes = 0; 9393 ei->disk_i_size = 0; 9394 ei->flags = 0; 9395 ei->csum_bytes = 0; 9396 ei->index_cnt = (u64)-1; 9397 ei->dir_index = 0; 9398 ei->last_unlink_trans = 0; 9399 ei->last_log_commit = 0; 9400 ei->delayed_iput_count = 0; 9401 9402 spin_lock_init(&ei->lock); 9403 ei->outstanding_extents = 0; 9404 ei->reserved_extents = 0; 9405 9406 ei->runtime_flags = 0; 9407 ei->force_compress = BTRFS_COMPRESS_NONE; 9408 9409 ei->delayed_node = NULL; 9410 9411 ei->i_otime.tv_sec = 0; 9412 ei->i_otime.tv_nsec = 0; 9413 9414 inode = &ei->vfs_inode; 9415 extent_map_tree_init(&ei->extent_tree); 9416 extent_io_tree_init(&ei->io_tree, inode); 9417 extent_io_tree_init(&ei->io_failure_tree, inode); 9418 ei->io_tree.track_uptodate = 1; 9419 ei->io_failure_tree.track_uptodate = 1; 9420 atomic_set(&ei->sync_writers, 0); 9421 mutex_init(&ei->log_mutex); 9422 mutex_init(&ei->delalloc_mutex); 9423 btrfs_ordered_inode_tree_init(&ei->ordered_tree); 9424 INIT_LIST_HEAD(&ei->delalloc_inodes); 9425 INIT_LIST_HEAD(&ei->delayed_iput); 9426 RB_CLEAR_NODE(&ei->rb_node); 9427 init_rwsem(&ei->dio_sem); 9428 9429 return inode; 9430 } 9431 9432 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 9433 void btrfs_test_destroy_inode(struct inode *inode) 9434 { 9435 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0); 9436 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); 9437 } 9438 #endif 9439 9440 static void btrfs_i_callback(struct rcu_head *head) 9441 { 9442 struct inode *inode = container_of(head, struct inode, i_rcu); 9443 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); 9444 } 9445 9446 void btrfs_destroy_inode(struct inode *inode) 9447 { 9448 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 9449 struct btrfs_ordered_extent *ordered; 9450 struct btrfs_root *root = BTRFS_I(inode)->root; 9451 9452 WARN_ON(!hlist_empty(&inode->i_dentry)); 9453 WARN_ON(inode->i_data.nrpages); 9454 WARN_ON(BTRFS_I(inode)->outstanding_extents); 9455 WARN_ON(BTRFS_I(inode)->reserved_extents); 9456 WARN_ON(BTRFS_I(inode)->delalloc_bytes); 9457 WARN_ON(BTRFS_I(inode)->new_delalloc_bytes); 9458 WARN_ON(BTRFS_I(inode)->csum_bytes); 9459 WARN_ON(BTRFS_I(inode)->defrag_bytes); 9460 9461 /* 9462 * This can happen where we create an inode, but somebody else also 9463 * created the same inode and we need to destroy the one we already 9464 * created. 9465 */ 9466 if (!root) 9467 goto free; 9468 9469 if (test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 9470 &BTRFS_I(inode)->runtime_flags)) { 9471 btrfs_info(fs_info, "inode %llu still on the orphan list", 9472 btrfs_ino(BTRFS_I(inode))); 9473 atomic_dec(&root->orphan_inodes); 9474 } 9475 9476 while (1) { 9477 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1); 9478 if (!ordered) 9479 break; 9480 else { 9481 btrfs_err(fs_info, 9482 "found ordered extent %llu %llu on inode cleanup", 9483 ordered->file_offset, ordered->len); 9484 btrfs_remove_ordered_extent(inode, ordered); 9485 btrfs_put_ordered_extent(ordered); 9486 btrfs_put_ordered_extent(ordered); 9487 } 9488 } 9489 btrfs_qgroup_check_reserved_leak(inode); 9490 inode_tree_del(inode); 9491 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0); 9492 free: 9493 call_rcu(&inode->i_rcu, btrfs_i_callback); 9494 } 9495 9496 int btrfs_drop_inode(struct inode *inode) 9497 { 9498 struct btrfs_root *root = BTRFS_I(inode)->root; 9499 9500 if (root == NULL) 9501 return 1; 9502 9503 /* the snap/subvol tree is on deleting */ 9504 if (btrfs_root_refs(&root->root_item) == 0) 9505 return 1; 9506 else 9507 return generic_drop_inode(inode); 9508 } 9509 9510 static void init_once(void *foo) 9511 { 9512 struct btrfs_inode *ei = (struct btrfs_inode *) foo; 9513 9514 inode_init_once(&ei->vfs_inode); 9515 } 9516 9517 void btrfs_destroy_cachep(void) 9518 { 9519 /* 9520 * Make sure all delayed rcu free inodes are flushed before we 9521 * destroy cache. 9522 */ 9523 rcu_barrier(); 9524 kmem_cache_destroy(btrfs_inode_cachep); 9525 kmem_cache_destroy(btrfs_trans_handle_cachep); 9526 kmem_cache_destroy(btrfs_path_cachep); 9527 kmem_cache_destroy(btrfs_free_space_cachep); 9528 } 9529 9530 int btrfs_init_cachep(void) 9531 { 9532 btrfs_inode_cachep = kmem_cache_create("btrfs_inode", 9533 sizeof(struct btrfs_inode), 0, 9534 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT, 9535 init_once); 9536 if (!btrfs_inode_cachep) 9537 goto fail; 9538 9539 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle", 9540 sizeof(struct btrfs_trans_handle), 0, 9541 SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL); 9542 if (!btrfs_trans_handle_cachep) 9543 goto fail; 9544 9545 btrfs_path_cachep = kmem_cache_create("btrfs_path", 9546 sizeof(struct btrfs_path), 0, 9547 SLAB_MEM_SPREAD, NULL); 9548 if (!btrfs_path_cachep) 9549 goto fail; 9550 9551 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space", 9552 sizeof(struct btrfs_free_space), 0, 9553 SLAB_MEM_SPREAD, NULL); 9554 if (!btrfs_free_space_cachep) 9555 goto fail; 9556 9557 return 0; 9558 fail: 9559 btrfs_destroy_cachep(); 9560 return -ENOMEM; 9561 } 9562 9563 static int btrfs_getattr(const struct path *path, struct kstat *stat, 9564 u32 request_mask, unsigned int flags) 9565 { 9566 u64 delalloc_bytes; 9567 struct inode *inode = d_inode(path->dentry); 9568 u32 blocksize = inode->i_sb->s_blocksize; 9569 u32 bi_flags = BTRFS_I(inode)->flags; 9570 9571 stat->result_mask |= STATX_BTIME; 9572 stat->btime.tv_sec = BTRFS_I(inode)->i_otime.tv_sec; 9573 stat->btime.tv_nsec = BTRFS_I(inode)->i_otime.tv_nsec; 9574 if (bi_flags & BTRFS_INODE_APPEND) 9575 stat->attributes |= STATX_ATTR_APPEND; 9576 if (bi_flags & BTRFS_INODE_COMPRESS) 9577 stat->attributes |= STATX_ATTR_COMPRESSED; 9578 if (bi_flags & BTRFS_INODE_IMMUTABLE) 9579 stat->attributes |= STATX_ATTR_IMMUTABLE; 9580 if (bi_flags & BTRFS_INODE_NODUMP) 9581 stat->attributes |= STATX_ATTR_NODUMP; 9582 9583 stat->attributes_mask |= (STATX_ATTR_APPEND | 9584 STATX_ATTR_COMPRESSED | 9585 STATX_ATTR_IMMUTABLE | 9586 STATX_ATTR_NODUMP); 9587 9588 generic_fillattr(inode, stat); 9589 stat->dev = BTRFS_I(inode)->root->anon_dev; 9590 9591 spin_lock(&BTRFS_I(inode)->lock); 9592 delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes; 9593 spin_unlock(&BTRFS_I(inode)->lock); 9594 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) + 9595 ALIGN(delalloc_bytes, blocksize)) >> 9; 9596 return 0; 9597 } 9598 9599 static int btrfs_rename_exchange(struct inode *old_dir, 9600 struct dentry *old_dentry, 9601 struct inode *new_dir, 9602 struct dentry *new_dentry) 9603 { 9604 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb); 9605 struct btrfs_trans_handle *trans; 9606 struct btrfs_root *root = BTRFS_I(old_dir)->root; 9607 struct btrfs_root *dest = BTRFS_I(new_dir)->root; 9608 struct inode *new_inode = new_dentry->d_inode; 9609 struct inode *old_inode = old_dentry->d_inode; 9610 struct timespec ctime = current_time(old_inode); 9611 struct dentry *parent; 9612 u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); 9613 u64 new_ino = btrfs_ino(BTRFS_I(new_inode)); 9614 u64 old_idx = 0; 9615 u64 new_idx = 0; 9616 u64 root_objectid; 9617 int ret; 9618 bool root_log_pinned = false; 9619 bool dest_log_pinned = false; 9620 9621 /* we only allow rename subvolume link between subvolumes */ 9622 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) 9623 return -EXDEV; 9624 9625 /* close the race window with snapshot create/destroy ioctl */ 9626 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9627 down_read(&fs_info->subvol_sem); 9628 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) 9629 down_read(&fs_info->subvol_sem); 9630 9631 /* 9632 * We want to reserve the absolute worst case amount of items. So if 9633 * both inodes are subvols and we need to unlink them then that would 9634 * require 4 item modifications, but if they are both normal inodes it 9635 * would require 5 item modifications, so we'll assume their normal 9636 * inodes. So 5 * 2 is 10, plus 2 for the new links, so 12 total items 9637 * should cover the worst case number of items we'll modify. 9638 */ 9639 trans = btrfs_start_transaction(root, 12); 9640 if (IS_ERR(trans)) { 9641 ret = PTR_ERR(trans); 9642 goto out_notrans; 9643 } 9644 9645 /* 9646 * We need to find a free sequence number both in the source and 9647 * in the destination directory for the exchange. 9648 */ 9649 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &old_idx); 9650 if (ret) 9651 goto out_fail; 9652 ret = btrfs_set_inode_index(BTRFS_I(old_dir), &new_idx); 9653 if (ret) 9654 goto out_fail; 9655 9656 BTRFS_I(old_inode)->dir_index = 0ULL; 9657 BTRFS_I(new_inode)->dir_index = 0ULL; 9658 9659 /* Reference for the source. */ 9660 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { 9661 /* force full log commit if subvolume involved. */ 9662 btrfs_set_log_full_commit(fs_info, trans); 9663 } else { 9664 btrfs_pin_log_trans(root); 9665 root_log_pinned = true; 9666 ret = btrfs_insert_inode_ref(trans, dest, 9667 new_dentry->d_name.name, 9668 new_dentry->d_name.len, 9669 old_ino, 9670 btrfs_ino(BTRFS_I(new_dir)), 9671 old_idx); 9672 if (ret) 9673 goto out_fail; 9674 } 9675 9676 /* And now for the dest. */ 9677 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { 9678 /* force full log commit if subvolume involved. */ 9679 btrfs_set_log_full_commit(fs_info, trans); 9680 } else { 9681 btrfs_pin_log_trans(dest); 9682 dest_log_pinned = true; 9683 ret = btrfs_insert_inode_ref(trans, root, 9684 old_dentry->d_name.name, 9685 old_dentry->d_name.len, 9686 new_ino, 9687 btrfs_ino(BTRFS_I(old_dir)), 9688 new_idx); 9689 if (ret) 9690 goto out_fail; 9691 } 9692 9693 /* Update inode version and ctime/mtime. */ 9694 inode_inc_iversion(old_dir); 9695 inode_inc_iversion(new_dir); 9696 inode_inc_iversion(old_inode); 9697 inode_inc_iversion(new_inode); 9698 old_dir->i_ctime = old_dir->i_mtime = ctime; 9699 new_dir->i_ctime = new_dir->i_mtime = ctime; 9700 old_inode->i_ctime = ctime; 9701 new_inode->i_ctime = ctime; 9702 9703 if (old_dentry->d_parent != new_dentry->d_parent) { 9704 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), 9705 BTRFS_I(old_inode), 1); 9706 btrfs_record_unlink_dir(trans, BTRFS_I(new_dir), 9707 BTRFS_I(new_inode), 1); 9708 } 9709 9710 /* src is a subvolume */ 9711 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { 9712 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; 9713 ret = btrfs_unlink_subvol(trans, root, old_dir, 9714 root_objectid, 9715 old_dentry->d_name.name, 9716 old_dentry->d_name.len); 9717 } else { /* src is an inode */ 9718 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir), 9719 BTRFS_I(old_dentry->d_inode), 9720 old_dentry->d_name.name, 9721 old_dentry->d_name.len); 9722 if (!ret) 9723 ret = btrfs_update_inode(trans, root, old_inode); 9724 } 9725 if (ret) { 9726 btrfs_abort_transaction(trans, ret); 9727 goto out_fail; 9728 } 9729 9730 /* dest is a subvolume */ 9731 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { 9732 root_objectid = BTRFS_I(new_inode)->root->root_key.objectid; 9733 ret = btrfs_unlink_subvol(trans, dest, new_dir, 9734 root_objectid, 9735 new_dentry->d_name.name, 9736 new_dentry->d_name.len); 9737 } else { /* dest is an inode */ 9738 ret = __btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir), 9739 BTRFS_I(new_dentry->d_inode), 9740 new_dentry->d_name.name, 9741 new_dentry->d_name.len); 9742 if (!ret) 9743 ret = btrfs_update_inode(trans, dest, new_inode); 9744 } 9745 if (ret) { 9746 btrfs_abort_transaction(trans, ret); 9747 goto out_fail; 9748 } 9749 9750 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), 9751 new_dentry->d_name.name, 9752 new_dentry->d_name.len, 0, old_idx); 9753 if (ret) { 9754 btrfs_abort_transaction(trans, ret); 9755 goto out_fail; 9756 } 9757 9758 ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode), 9759 old_dentry->d_name.name, 9760 old_dentry->d_name.len, 0, new_idx); 9761 if (ret) { 9762 btrfs_abort_transaction(trans, ret); 9763 goto out_fail; 9764 } 9765 9766 if (old_inode->i_nlink == 1) 9767 BTRFS_I(old_inode)->dir_index = old_idx; 9768 if (new_inode->i_nlink == 1) 9769 BTRFS_I(new_inode)->dir_index = new_idx; 9770 9771 if (root_log_pinned) { 9772 parent = new_dentry->d_parent; 9773 btrfs_log_new_name(trans, BTRFS_I(old_inode), BTRFS_I(old_dir), 9774 parent); 9775 btrfs_end_log_trans(root); 9776 root_log_pinned = false; 9777 } 9778 if (dest_log_pinned) { 9779 parent = old_dentry->d_parent; 9780 btrfs_log_new_name(trans, BTRFS_I(new_inode), BTRFS_I(new_dir), 9781 parent); 9782 btrfs_end_log_trans(dest); 9783 dest_log_pinned = false; 9784 } 9785 out_fail: 9786 /* 9787 * If we have pinned a log and an error happened, we unpin tasks 9788 * trying to sync the log and force them to fallback to a transaction 9789 * commit if the log currently contains any of the inodes involved in 9790 * this rename operation (to ensure we do not persist a log with an 9791 * inconsistent state for any of these inodes or leading to any 9792 * inconsistencies when replayed). If the transaction was aborted, the 9793 * abortion reason is propagated to userspace when attempting to commit 9794 * the transaction. If the log does not contain any of these inodes, we 9795 * allow the tasks to sync it. 9796 */ 9797 if (ret && (root_log_pinned || dest_log_pinned)) { 9798 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) || 9799 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) || 9800 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) || 9801 (new_inode && 9802 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation))) 9803 btrfs_set_log_full_commit(fs_info, trans); 9804 9805 if (root_log_pinned) { 9806 btrfs_end_log_trans(root); 9807 root_log_pinned = false; 9808 } 9809 if (dest_log_pinned) { 9810 btrfs_end_log_trans(dest); 9811 dest_log_pinned = false; 9812 } 9813 } 9814 ret = btrfs_end_transaction(trans); 9815 out_notrans: 9816 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) 9817 up_read(&fs_info->subvol_sem); 9818 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9819 up_read(&fs_info->subvol_sem); 9820 9821 return ret; 9822 } 9823 9824 static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans, 9825 struct btrfs_root *root, 9826 struct inode *dir, 9827 struct dentry *dentry) 9828 { 9829 int ret; 9830 struct inode *inode; 9831 u64 objectid; 9832 u64 index; 9833 9834 ret = btrfs_find_free_ino(root, &objectid); 9835 if (ret) 9836 return ret; 9837 9838 inode = btrfs_new_inode(trans, root, dir, 9839 dentry->d_name.name, 9840 dentry->d_name.len, 9841 btrfs_ino(BTRFS_I(dir)), 9842 objectid, 9843 S_IFCHR | WHITEOUT_MODE, 9844 &index); 9845 9846 if (IS_ERR(inode)) { 9847 ret = PTR_ERR(inode); 9848 return ret; 9849 } 9850 9851 inode->i_op = &btrfs_special_inode_operations; 9852 init_special_inode(inode, inode->i_mode, 9853 WHITEOUT_DEV); 9854 9855 ret = btrfs_init_inode_security(trans, inode, dir, 9856 &dentry->d_name); 9857 if (ret) 9858 goto out; 9859 9860 ret = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, 9861 BTRFS_I(inode), 0, index); 9862 if (ret) 9863 goto out; 9864 9865 ret = btrfs_update_inode(trans, root, inode); 9866 out: 9867 unlock_new_inode(inode); 9868 if (ret) 9869 inode_dec_link_count(inode); 9870 iput(inode); 9871 9872 return ret; 9873 } 9874 9875 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, 9876 struct inode *new_dir, struct dentry *new_dentry, 9877 unsigned int flags) 9878 { 9879 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb); 9880 struct btrfs_trans_handle *trans; 9881 unsigned int trans_num_items; 9882 struct btrfs_root *root = BTRFS_I(old_dir)->root; 9883 struct btrfs_root *dest = BTRFS_I(new_dir)->root; 9884 struct inode *new_inode = d_inode(new_dentry); 9885 struct inode *old_inode = d_inode(old_dentry); 9886 u64 index = 0; 9887 u64 root_objectid; 9888 int ret; 9889 u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); 9890 bool log_pinned = false; 9891 9892 if (btrfs_ino(BTRFS_I(new_dir)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) 9893 return -EPERM; 9894 9895 /* we only allow rename subvolume link between subvolumes */ 9896 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) 9897 return -EXDEV; 9898 9899 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || 9900 (new_inode && btrfs_ino(BTRFS_I(new_inode)) == BTRFS_FIRST_FREE_OBJECTID)) 9901 return -ENOTEMPTY; 9902 9903 if (S_ISDIR(old_inode->i_mode) && new_inode && 9904 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) 9905 return -ENOTEMPTY; 9906 9907 9908 /* check for collisions, even if the name isn't there */ 9909 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino, 9910 new_dentry->d_name.name, 9911 new_dentry->d_name.len); 9912 9913 if (ret) { 9914 if (ret == -EEXIST) { 9915 /* we shouldn't get 9916 * eexist without a new_inode */ 9917 if (WARN_ON(!new_inode)) { 9918 return ret; 9919 } 9920 } else { 9921 /* maybe -EOVERFLOW */ 9922 return ret; 9923 } 9924 } 9925 ret = 0; 9926 9927 /* 9928 * we're using rename to replace one file with another. Start IO on it 9929 * now so we don't add too much work to the end of the transaction 9930 */ 9931 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size) 9932 filemap_flush(old_inode->i_mapping); 9933 9934 /* close the racy window with snapshot create/destroy ioctl */ 9935 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9936 down_read(&fs_info->subvol_sem); 9937 /* 9938 * We want to reserve the absolute worst case amount of items. So if 9939 * both inodes are subvols and we need to unlink them then that would 9940 * require 4 item modifications, but if they are both normal inodes it 9941 * would require 5 item modifications, so we'll assume they are normal 9942 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items 9943 * should cover the worst case number of items we'll modify. 9944 * If our rename has the whiteout flag, we need more 5 units for the 9945 * new inode (1 inode item, 1 inode ref, 2 dir items and 1 xattr item 9946 * when selinux is enabled). 9947 */ 9948 trans_num_items = 11; 9949 if (flags & RENAME_WHITEOUT) 9950 trans_num_items += 5; 9951 trans = btrfs_start_transaction(root, trans_num_items); 9952 if (IS_ERR(trans)) { 9953 ret = PTR_ERR(trans); 9954 goto out_notrans; 9955 } 9956 9957 if (dest != root) 9958 btrfs_record_root_in_trans(trans, dest); 9959 9960 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &index); 9961 if (ret) 9962 goto out_fail; 9963 9964 BTRFS_I(old_inode)->dir_index = 0ULL; 9965 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { 9966 /* force full log commit if subvolume involved. */ 9967 btrfs_set_log_full_commit(fs_info, trans); 9968 } else { 9969 btrfs_pin_log_trans(root); 9970 log_pinned = true; 9971 ret = btrfs_insert_inode_ref(trans, dest, 9972 new_dentry->d_name.name, 9973 new_dentry->d_name.len, 9974 old_ino, 9975 btrfs_ino(BTRFS_I(new_dir)), index); 9976 if (ret) 9977 goto out_fail; 9978 } 9979 9980 inode_inc_iversion(old_dir); 9981 inode_inc_iversion(new_dir); 9982 inode_inc_iversion(old_inode); 9983 old_dir->i_ctime = old_dir->i_mtime = 9984 new_dir->i_ctime = new_dir->i_mtime = 9985 old_inode->i_ctime = current_time(old_dir); 9986 9987 if (old_dentry->d_parent != new_dentry->d_parent) 9988 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), 9989 BTRFS_I(old_inode), 1); 9990 9991 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { 9992 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; 9993 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid, 9994 old_dentry->d_name.name, 9995 old_dentry->d_name.len); 9996 } else { 9997 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir), 9998 BTRFS_I(d_inode(old_dentry)), 9999 old_dentry->d_name.name, 10000 old_dentry->d_name.len); 10001 if (!ret) 10002 ret = btrfs_update_inode(trans, root, old_inode); 10003 } 10004 if (ret) { 10005 btrfs_abort_transaction(trans, ret); 10006 goto out_fail; 10007 } 10008 10009 if (new_inode) { 10010 inode_inc_iversion(new_inode); 10011 new_inode->i_ctime = current_time(new_inode); 10012 if (unlikely(btrfs_ino(BTRFS_I(new_inode)) == 10013 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { 10014 root_objectid = BTRFS_I(new_inode)->location.objectid; 10015 ret = btrfs_unlink_subvol(trans, dest, new_dir, 10016 root_objectid, 10017 new_dentry->d_name.name, 10018 new_dentry->d_name.len); 10019 BUG_ON(new_inode->i_nlink == 0); 10020 } else { 10021 ret = btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir), 10022 BTRFS_I(d_inode(new_dentry)), 10023 new_dentry->d_name.name, 10024 new_dentry->d_name.len); 10025 } 10026 if (!ret && new_inode->i_nlink == 0) 10027 ret = btrfs_orphan_add(trans, 10028 BTRFS_I(d_inode(new_dentry))); 10029 if (ret) { 10030 btrfs_abort_transaction(trans, ret); 10031 goto out_fail; 10032 } 10033 } 10034 10035 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), 10036 new_dentry->d_name.name, 10037 new_dentry->d_name.len, 0, index); 10038 if (ret) { 10039 btrfs_abort_transaction(trans, ret); 10040 goto out_fail; 10041 } 10042 10043 if (old_inode->i_nlink == 1) 10044 BTRFS_I(old_inode)->dir_index = index; 10045 10046 if (log_pinned) { 10047 struct dentry *parent = new_dentry->d_parent; 10048 10049 btrfs_log_new_name(trans, BTRFS_I(old_inode), BTRFS_I(old_dir), 10050 parent); 10051 btrfs_end_log_trans(root); 10052 log_pinned = false; 10053 } 10054 10055 if (flags & RENAME_WHITEOUT) { 10056 ret = btrfs_whiteout_for_rename(trans, root, old_dir, 10057 old_dentry); 10058 10059 if (ret) { 10060 btrfs_abort_transaction(trans, ret); 10061 goto out_fail; 10062 } 10063 } 10064 out_fail: 10065 /* 10066 * If we have pinned the log and an error happened, we unpin tasks 10067 * trying to sync the log and force them to fallback to a transaction 10068 * commit if the log currently contains any of the inodes involved in 10069 * this rename operation (to ensure we do not persist a log with an 10070 * inconsistent state for any of these inodes or leading to any 10071 * inconsistencies when replayed). If the transaction was aborted, the 10072 * abortion reason is propagated to userspace when attempting to commit 10073 * the transaction. If the log does not contain any of these inodes, we 10074 * allow the tasks to sync it. 10075 */ 10076 if (ret && log_pinned) { 10077 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) || 10078 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) || 10079 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) || 10080 (new_inode && 10081 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation))) 10082 btrfs_set_log_full_commit(fs_info, trans); 10083 10084 btrfs_end_log_trans(root); 10085 log_pinned = false; 10086 } 10087 btrfs_end_transaction(trans); 10088 out_notrans: 10089 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 10090 up_read(&fs_info->subvol_sem); 10091 10092 return ret; 10093 } 10094 10095 static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry, 10096 struct inode *new_dir, struct dentry *new_dentry, 10097 unsigned int flags) 10098 { 10099 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 10100 return -EINVAL; 10101 10102 if (flags & RENAME_EXCHANGE) 10103 return btrfs_rename_exchange(old_dir, old_dentry, new_dir, 10104 new_dentry); 10105 10106 return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 10107 } 10108 10109 static void btrfs_run_delalloc_work(struct btrfs_work *work) 10110 { 10111 struct btrfs_delalloc_work *delalloc_work; 10112 struct inode *inode; 10113 10114 delalloc_work = container_of(work, struct btrfs_delalloc_work, 10115 work); 10116 inode = delalloc_work->inode; 10117 filemap_flush(inode->i_mapping); 10118 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 10119 &BTRFS_I(inode)->runtime_flags)) 10120 filemap_flush(inode->i_mapping); 10121 10122 if (delalloc_work->delay_iput) 10123 btrfs_add_delayed_iput(inode); 10124 else 10125 iput(inode); 10126 complete(&delalloc_work->completion); 10127 } 10128 10129 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode, 10130 int delay_iput) 10131 { 10132 struct btrfs_delalloc_work *work; 10133 10134 work = kmalloc(sizeof(*work), GFP_NOFS); 10135 if (!work) 10136 return NULL; 10137 10138 init_completion(&work->completion); 10139 INIT_LIST_HEAD(&work->list); 10140 work->inode = inode; 10141 work->delay_iput = delay_iput; 10142 WARN_ON_ONCE(!inode); 10143 btrfs_init_work(&work->work, btrfs_flush_delalloc_helper, 10144 btrfs_run_delalloc_work, NULL, NULL); 10145 10146 return work; 10147 } 10148 10149 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work) 10150 { 10151 wait_for_completion(&work->completion); 10152 kfree(work); 10153 } 10154 10155 /* 10156 * some fairly slow code that needs optimization. This walks the list 10157 * of all the inodes with pending delalloc and forces them to disk. 10158 */ 10159 static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput, 10160 int nr) 10161 { 10162 struct btrfs_inode *binode; 10163 struct inode *inode; 10164 struct btrfs_delalloc_work *work, *next; 10165 struct list_head works; 10166 struct list_head splice; 10167 int ret = 0; 10168 10169 INIT_LIST_HEAD(&works); 10170 INIT_LIST_HEAD(&splice); 10171 10172 mutex_lock(&root->delalloc_mutex); 10173 spin_lock(&root->delalloc_lock); 10174 list_splice_init(&root->delalloc_inodes, &splice); 10175 while (!list_empty(&splice)) { 10176 binode = list_entry(splice.next, struct btrfs_inode, 10177 delalloc_inodes); 10178 10179 list_move_tail(&binode->delalloc_inodes, 10180 &root->delalloc_inodes); 10181 inode = igrab(&binode->vfs_inode); 10182 if (!inode) { 10183 cond_resched_lock(&root->delalloc_lock); 10184 continue; 10185 } 10186 spin_unlock(&root->delalloc_lock); 10187 10188 work = btrfs_alloc_delalloc_work(inode, delay_iput); 10189 if (!work) { 10190 if (delay_iput) 10191 btrfs_add_delayed_iput(inode); 10192 else 10193 iput(inode); 10194 ret = -ENOMEM; 10195 goto out; 10196 } 10197 list_add_tail(&work->list, &works); 10198 btrfs_queue_work(root->fs_info->flush_workers, 10199 &work->work); 10200 ret++; 10201 if (nr != -1 && ret >= nr) 10202 goto out; 10203 cond_resched(); 10204 spin_lock(&root->delalloc_lock); 10205 } 10206 spin_unlock(&root->delalloc_lock); 10207 10208 out: 10209 list_for_each_entry_safe(work, next, &works, list) { 10210 list_del_init(&work->list); 10211 btrfs_wait_and_free_delalloc_work(work); 10212 } 10213 10214 if (!list_empty_careful(&splice)) { 10215 spin_lock(&root->delalloc_lock); 10216 list_splice_tail(&splice, &root->delalloc_inodes); 10217 spin_unlock(&root->delalloc_lock); 10218 } 10219 mutex_unlock(&root->delalloc_mutex); 10220 return ret; 10221 } 10222 10223 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput) 10224 { 10225 struct btrfs_fs_info *fs_info = root->fs_info; 10226 int ret; 10227 10228 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 10229 return -EROFS; 10230 10231 ret = __start_delalloc_inodes(root, delay_iput, -1); 10232 if (ret > 0) 10233 ret = 0; 10234 /* 10235 * the filemap_flush will queue IO into the worker threads, but 10236 * we have to make sure the IO is actually started and that 10237 * ordered extents get created before we return 10238 */ 10239 atomic_inc(&fs_info->async_submit_draining); 10240 while (atomic_read(&fs_info->nr_async_submits) || 10241 atomic_read(&fs_info->async_delalloc_pages)) { 10242 wait_event(fs_info->async_submit_wait, 10243 (atomic_read(&fs_info->nr_async_submits) == 0 && 10244 atomic_read(&fs_info->async_delalloc_pages) == 0)); 10245 } 10246 atomic_dec(&fs_info->async_submit_draining); 10247 return ret; 10248 } 10249 10250 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int delay_iput, 10251 int nr) 10252 { 10253 struct btrfs_root *root; 10254 struct list_head splice; 10255 int ret; 10256 10257 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 10258 return -EROFS; 10259 10260 INIT_LIST_HEAD(&splice); 10261 10262 mutex_lock(&fs_info->delalloc_root_mutex); 10263 spin_lock(&fs_info->delalloc_root_lock); 10264 list_splice_init(&fs_info->delalloc_roots, &splice); 10265 while (!list_empty(&splice) && nr) { 10266 root = list_first_entry(&splice, struct btrfs_root, 10267 delalloc_root); 10268 root = btrfs_grab_fs_root(root); 10269 BUG_ON(!root); 10270 list_move_tail(&root->delalloc_root, 10271 &fs_info->delalloc_roots); 10272 spin_unlock(&fs_info->delalloc_root_lock); 10273 10274 ret = __start_delalloc_inodes(root, delay_iput, nr); 10275 btrfs_put_fs_root(root); 10276 if (ret < 0) 10277 goto out; 10278 10279 if (nr != -1) { 10280 nr -= ret; 10281 WARN_ON(nr < 0); 10282 } 10283 spin_lock(&fs_info->delalloc_root_lock); 10284 } 10285 spin_unlock(&fs_info->delalloc_root_lock); 10286 10287 ret = 0; 10288 atomic_inc(&fs_info->async_submit_draining); 10289 while (atomic_read(&fs_info->nr_async_submits) || 10290 atomic_read(&fs_info->async_delalloc_pages)) { 10291 wait_event(fs_info->async_submit_wait, 10292 (atomic_read(&fs_info->nr_async_submits) == 0 && 10293 atomic_read(&fs_info->async_delalloc_pages) == 0)); 10294 } 10295 atomic_dec(&fs_info->async_submit_draining); 10296 out: 10297 if (!list_empty_careful(&splice)) { 10298 spin_lock(&fs_info->delalloc_root_lock); 10299 list_splice_tail(&splice, &fs_info->delalloc_roots); 10300 spin_unlock(&fs_info->delalloc_root_lock); 10301 } 10302 mutex_unlock(&fs_info->delalloc_root_mutex); 10303 return ret; 10304 } 10305 10306 static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 10307 const char *symname) 10308 { 10309 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 10310 struct btrfs_trans_handle *trans; 10311 struct btrfs_root *root = BTRFS_I(dir)->root; 10312 struct btrfs_path *path; 10313 struct btrfs_key key; 10314 struct inode *inode = NULL; 10315 int err; 10316 int drop_inode = 0; 10317 u64 objectid; 10318 u64 index = 0; 10319 int name_len; 10320 int datasize; 10321 unsigned long ptr; 10322 struct btrfs_file_extent_item *ei; 10323 struct extent_buffer *leaf; 10324 10325 name_len = strlen(symname); 10326 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info)) 10327 return -ENAMETOOLONG; 10328 10329 /* 10330 * 2 items for inode item and ref 10331 * 2 items for dir items 10332 * 1 item for updating parent inode item 10333 * 1 item for the inline extent item 10334 * 1 item for xattr if selinux is on 10335 */ 10336 trans = btrfs_start_transaction(root, 7); 10337 if (IS_ERR(trans)) 10338 return PTR_ERR(trans); 10339 10340 err = btrfs_find_free_ino(root, &objectid); 10341 if (err) 10342 goto out_unlock; 10343 10344 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 10345 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), 10346 objectid, S_IFLNK|S_IRWXUGO, &index); 10347 if (IS_ERR(inode)) { 10348 err = PTR_ERR(inode); 10349 goto out_unlock; 10350 } 10351 10352 /* 10353 * If the active LSM wants to access the inode during 10354 * d_instantiate it needs these. Smack checks to see 10355 * if the filesystem supports xattrs by looking at the 10356 * ops vector. 10357 */ 10358 inode->i_fop = &btrfs_file_operations; 10359 inode->i_op = &btrfs_file_inode_operations; 10360 inode->i_mapping->a_ops = &btrfs_aops; 10361 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 10362 10363 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 10364 if (err) 10365 goto out_unlock_inode; 10366 10367 path = btrfs_alloc_path(); 10368 if (!path) { 10369 err = -ENOMEM; 10370 goto out_unlock_inode; 10371 } 10372 key.objectid = btrfs_ino(BTRFS_I(inode)); 10373 key.offset = 0; 10374 key.type = BTRFS_EXTENT_DATA_KEY; 10375 datasize = btrfs_file_extent_calc_inline_size(name_len); 10376 err = btrfs_insert_empty_item(trans, root, path, &key, 10377 datasize); 10378 if (err) { 10379 btrfs_free_path(path); 10380 goto out_unlock_inode; 10381 } 10382 leaf = path->nodes[0]; 10383 ei = btrfs_item_ptr(leaf, path->slots[0], 10384 struct btrfs_file_extent_item); 10385 btrfs_set_file_extent_generation(leaf, ei, trans->transid); 10386 btrfs_set_file_extent_type(leaf, ei, 10387 BTRFS_FILE_EXTENT_INLINE); 10388 btrfs_set_file_extent_encryption(leaf, ei, 0); 10389 btrfs_set_file_extent_compression(leaf, ei, 0); 10390 btrfs_set_file_extent_other_encoding(leaf, ei, 0); 10391 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); 10392 10393 ptr = btrfs_file_extent_inline_start(ei); 10394 write_extent_buffer(leaf, symname, ptr, name_len); 10395 btrfs_mark_buffer_dirty(leaf); 10396 btrfs_free_path(path); 10397 10398 inode->i_op = &btrfs_symlink_inode_operations; 10399 inode_nohighmem(inode); 10400 inode->i_mapping->a_ops = &btrfs_symlink_aops; 10401 inode_set_bytes(inode, name_len); 10402 btrfs_i_size_write(BTRFS_I(inode), name_len); 10403 err = btrfs_update_inode(trans, root, inode); 10404 /* 10405 * Last step, add directory indexes for our symlink inode. This is the 10406 * last step to avoid extra cleanup of these indexes if an error happens 10407 * elsewhere above. 10408 */ 10409 if (!err) 10410 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, 10411 BTRFS_I(inode), 0, index); 10412 if (err) { 10413 drop_inode = 1; 10414 goto out_unlock_inode; 10415 } 10416 10417 unlock_new_inode(inode); 10418 d_instantiate(dentry, inode); 10419 10420 out_unlock: 10421 btrfs_end_transaction(trans); 10422 if (drop_inode) { 10423 inode_dec_link_count(inode); 10424 iput(inode); 10425 } 10426 btrfs_btree_balance_dirty(fs_info); 10427 return err; 10428 10429 out_unlock_inode: 10430 drop_inode = 1; 10431 unlock_new_inode(inode); 10432 goto out_unlock; 10433 } 10434 10435 static int __btrfs_prealloc_file_range(struct inode *inode, int mode, 10436 u64 start, u64 num_bytes, u64 min_size, 10437 loff_t actual_len, u64 *alloc_hint, 10438 struct btrfs_trans_handle *trans) 10439 { 10440 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 10441 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 10442 struct extent_map *em; 10443 struct btrfs_root *root = BTRFS_I(inode)->root; 10444 struct btrfs_key ins; 10445 u64 cur_offset = start; 10446 u64 i_size; 10447 u64 cur_bytes; 10448 u64 last_alloc = (u64)-1; 10449 int ret = 0; 10450 bool own_trans = true; 10451 u64 end = start + num_bytes - 1; 10452 10453 if (trans) 10454 own_trans = false; 10455 while (num_bytes > 0) { 10456 if (own_trans) { 10457 trans = btrfs_start_transaction(root, 3); 10458 if (IS_ERR(trans)) { 10459 ret = PTR_ERR(trans); 10460 break; 10461 } 10462 } 10463 10464 cur_bytes = min_t(u64, num_bytes, SZ_256M); 10465 cur_bytes = max(cur_bytes, min_size); 10466 /* 10467 * If we are severely fragmented we could end up with really 10468 * small allocations, so if the allocator is returning small 10469 * chunks lets make its job easier by only searching for those 10470 * sized chunks. 10471 */ 10472 cur_bytes = min(cur_bytes, last_alloc); 10473 ret = btrfs_reserve_extent(root, cur_bytes, cur_bytes, 10474 min_size, 0, *alloc_hint, &ins, 1, 0); 10475 if (ret) { 10476 if (own_trans) 10477 btrfs_end_transaction(trans); 10478 break; 10479 } 10480 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 10481 10482 last_alloc = ins.offset; 10483 ret = insert_reserved_file_extent(trans, inode, 10484 cur_offset, ins.objectid, 10485 ins.offset, ins.offset, 10486 ins.offset, 0, 0, 0, 10487 BTRFS_FILE_EXTENT_PREALLOC); 10488 if (ret) { 10489 btrfs_free_reserved_extent(fs_info, ins.objectid, 10490 ins.offset, 0); 10491 btrfs_abort_transaction(trans, ret); 10492 if (own_trans) 10493 btrfs_end_transaction(trans); 10494 break; 10495 } 10496 10497 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, 10498 cur_offset + ins.offset -1, 0); 10499 10500 em = alloc_extent_map(); 10501 if (!em) { 10502 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 10503 &BTRFS_I(inode)->runtime_flags); 10504 goto next; 10505 } 10506 10507 em->start = cur_offset; 10508 em->orig_start = cur_offset; 10509 em->len = ins.offset; 10510 em->block_start = ins.objectid; 10511 em->block_len = ins.offset; 10512 em->orig_block_len = ins.offset; 10513 em->ram_bytes = ins.offset; 10514 em->bdev = fs_info->fs_devices->latest_bdev; 10515 set_bit(EXTENT_FLAG_PREALLOC, &em->flags); 10516 em->generation = trans->transid; 10517 10518 while (1) { 10519 write_lock(&em_tree->lock); 10520 ret = add_extent_mapping(em_tree, em, 1); 10521 write_unlock(&em_tree->lock); 10522 if (ret != -EEXIST) 10523 break; 10524 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, 10525 cur_offset + ins.offset - 1, 10526 0); 10527 } 10528 free_extent_map(em); 10529 next: 10530 num_bytes -= ins.offset; 10531 cur_offset += ins.offset; 10532 *alloc_hint = ins.objectid + ins.offset; 10533 10534 inode_inc_iversion(inode); 10535 inode->i_ctime = current_time(inode); 10536 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC; 10537 if (!(mode & FALLOC_FL_KEEP_SIZE) && 10538 (actual_len > inode->i_size) && 10539 (cur_offset > inode->i_size)) { 10540 if (cur_offset > actual_len) 10541 i_size = actual_len; 10542 else 10543 i_size = cur_offset; 10544 i_size_write(inode, i_size); 10545 btrfs_ordered_update_i_size(inode, i_size, NULL); 10546 } 10547 10548 ret = btrfs_update_inode(trans, root, inode); 10549 10550 if (ret) { 10551 btrfs_abort_transaction(trans, ret); 10552 if (own_trans) 10553 btrfs_end_transaction(trans); 10554 break; 10555 } 10556 10557 if (own_trans) 10558 btrfs_end_transaction(trans); 10559 } 10560 if (cur_offset < end) 10561 btrfs_free_reserved_data_space(inode, NULL, cur_offset, 10562 end - cur_offset + 1); 10563 return ret; 10564 } 10565 10566 int btrfs_prealloc_file_range(struct inode *inode, int mode, 10567 u64 start, u64 num_bytes, u64 min_size, 10568 loff_t actual_len, u64 *alloc_hint) 10569 { 10570 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, 10571 min_size, actual_len, alloc_hint, 10572 NULL); 10573 } 10574 10575 int btrfs_prealloc_file_range_trans(struct inode *inode, 10576 struct btrfs_trans_handle *trans, int mode, 10577 u64 start, u64 num_bytes, u64 min_size, 10578 loff_t actual_len, u64 *alloc_hint) 10579 { 10580 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, 10581 min_size, actual_len, alloc_hint, trans); 10582 } 10583 10584 static int btrfs_set_page_dirty(struct page *page) 10585 { 10586 return __set_page_dirty_nobuffers(page); 10587 } 10588 10589 static int btrfs_permission(struct inode *inode, int mask) 10590 { 10591 struct btrfs_root *root = BTRFS_I(inode)->root; 10592 umode_t mode = inode->i_mode; 10593 10594 if (mask & MAY_WRITE && 10595 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) { 10596 if (btrfs_root_readonly(root)) 10597 return -EROFS; 10598 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) 10599 return -EACCES; 10600 } 10601 return generic_permission(inode, mask); 10602 } 10603 10604 static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 10605 { 10606 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 10607 struct btrfs_trans_handle *trans; 10608 struct btrfs_root *root = BTRFS_I(dir)->root; 10609 struct inode *inode = NULL; 10610 u64 objectid; 10611 u64 index; 10612 int ret = 0; 10613 10614 /* 10615 * 5 units required for adding orphan entry 10616 */ 10617 trans = btrfs_start_transaction(root, 5); 10618 if (IS_ERR(trans)) 10619 return PTR_ERR(trans); 10620 10621 ret = btrfs_find_free_ino(root, &objectid); 10622 if (ret) 10623 goto out; 10624 10625 inode = btrfs_new_inode(trans, root, dir, NULL, 0, 10626 btrfs_ino(BTRFS_I(dir)), objectid, mode, &index); 10627 if (IS_ERR(inode)) { 10628 ret = PTR_ERR(inode); 10629 inode = NULL; 10630 goto out; 10631 } 10632 10633 inode->i_fop = &btrfs_file_operations; 10634 inode->i_op = &btrfs_file_inode_operations; 10635 10636 inode->i_mapping->a_ops = &btrfs_aops; 10637 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 10638 10639 ret = btrfs_init_inode_security(trans, inode, dir, NULL); 10640 if (ret) 10641 goto out_inode; 10642 10643 ret = btrfs_update_inode(trans, root, inode); 10644 if (ret) 10645 goto out_inode; 10646 ret = btrfs_orphan_add(trans, BTRFS_I(inode)); 10647 if (ret) 10648 goto out_inode; 10649 10650 /* 10651 * We set number of links to 0 in btrfs_new_inode(), and here we set 10652 * it to 1 because d_tmpfile() will issue a warning if the count is 0, 10653 * through: 10654 * 10655 * d_tmpfile() -> inode_dec_link_count() -> drop_nlink() 10656 */ 10657 set_nlink(inode, 1); 10658 unlock_new_inode(inode); 10659 d_tmpfile(dentry, inode); 10660 mark_inode_dirty(inode); 10661 10662 out: 10663 btrfs_end_transaction(trans); 10664 if (ret) 10665 iput(inode); 10666 btrfs_balance_delayed_items(fs_info); 10667 btrfs_btree_balance_dirty(fs_info); 10668 return ret; 10669 10670 out_inode: 10671 unlock_new_inode(inode); 10672 goto out; 10673 10674 } 10675 10676 __attribute__((const)) 10677 static int btrfs_readpage_io_failed_hook(struct page *page, int failed_mirror) 10678 { 10679 return -EAGAIN; 10680 } 10681 10682 static struct btrfs_fs_info *iotree_fs_info(void *private_data) 10683 { 10684 struct inode *inode = private_data; 10685 return btrfs_sb(inode->i_sb); 10686 } 10687 10688 static void btrfs_check_extent_io_range(void *private_data, const char *caller, 10689 u64 start, u64 end) 10690 { 10691 struct inode *inode = private_data; 10692 u64 isize; 10693 10694 isize = i_size_read(inode); 10695 if (end >= PAGE_SIZE && (end % 2) == 0 && end != isize - 1) { 10696 btrfs_debug_rl(BTRFS_I(inode)->root->fs_info, 10697 "%s: ino %llu isize %llu odd range [%llu,%llu]", 10698 caller, btrfs_ino(BTRFS_I(inode)), isize, start, end); 10699 } 10700 } 10701 10702 void btrfs_set_range_writeback(void *private_data, u64 start, u64 end) 10703 { 10704 struct inode *inode = private_data; 10705 unsigned long index = start >> PAGE_SHIFT; 10706 unsigned long end_index = end >> PAGE_SHIFT; 10707 struct page *page; 10708 10709 while (index <= end_index) { 10710 page = find_get_page(inode->i_mapping, index); 10711 ASSERT(page); /* Pages should be in the extent_io_tree */ 10712 set_page_writeback(page); 10713 put_page(page); 10714 index++; 10715 } 10716 } 10717 10718 static const struct inode_operations btrfs_dir_inode_operations = { 10719 .getattr = btrfs_getattr, 10720 .lookup = btrfs_lookup, 10721 .create = btrfs_create, 10722 .unlink = btrfs_unlink, 10723 .link = btrfs_link, 10724 .mkdir = btrfs_mkdir, 10725 .rmdir = btrfs_rmdir, 10726 .rename = btrfs_rename2, 10727 .symlink = btrfs_symlink, 10728 .setattr = btrfs_setattr, 10729 .mknod = btrfs_mknod, 10730 .listxattr = btrfs_listxattr, 10731 .permission = btrfs_permission, 10732 .get_acl = btrfs_get_acl, 10733 .set_acl = btrfs_set_acl, 10734 .update_time = btrfs_update_time, 10735 .tmpfile = btrfs_tmpfile, 10736 }; 10737 static const struct inode_operations btrfs_dir_ro_inode_operations = { 10738 .lookup = btrfs_lookup, 10739 .permission = btrfs_permission, 10740 .update_time = btrfs_update_time, 10741 }; 10742 10743 static const struct file_operations btrfs_dir_file_operations = { 10744 .llseek = generic_file_llseek, 10745 .read = generic_read_dir, 10746 .iterate_shared = btrfs_real_readdir, 10747 .unlocked_ioctl = btrfs_ioctl, 10748 #ifdef CONFIG_COMPAT 10749 .compat_ioctl = btrfs_compat_ioctl, 10750 #endif 10751 .release = btrfs_release_file, 10752 .fsync = btrfs_sync_file, 10753 }; 10754 10755 static const struct extent_io_ops btrfs_extent_io_ops = { 10756 /* mandatory callbacks */ 10757 .submit_bio_hook = btrfs_submit_bio_hook, 10758 .readpage_end_io_hook = btrfs_readpage_end_io_hook, 10759 .merge_bio_hook = btrfs_merge_bio_hook, 10760 .readpage_io_failed_hook = btrfs_readpage_io_failed_hook, 10761 .tree_fs_info = iotree_fs_info, 10762 .set_range_writeback = btrfs_set_range_writeback, 10763 10764 /* optional callbacks */ 10765 .fill_delalloc = run_delalloc_range, 10766 .writepage_end_io_hook = btrfs_writepage_end_io_hook, 10767 .writepage_start_hook = btrfs_writepage_start_hook, 10768 .set_bit_hook = btrfs_set_bit_hook, 10769 .clear_bit_hook = btrfs_clear_bit_hook, 10770 .merge_extent_hook = btrfs_merge_extent_hook, 10771 .split_extent_hook = btrfs_split_extent_hook, 10772 .check_extent_io_range = btrfs_check_extent_io_range, 10773 }; 10774 10775 /* 10776 * btrfs doesn't support the bmap operation because swapfiles 10777 * use bmap to make a mapping of extents in the file. They assume 10778 * these extents won't change over the life of the file and they 10779 * use the bmap result to do IO directly to the drive. 10780 * 10781 * the btrfs bmap call would return logical addresses that aren't 10782 * suitable for IO and they also will change frequently as COW 10783 * operations happen. So, swapfile + btrfs == corruption. 10784 * 10785 * For now we're avoiding this by dropping bmap. 10786 */ 10787 static const struct address_space_operations btrfs_aops = { 10788 .readpage = btrfs_readpage, 10789 .writepage = btrfs_writepage, 10790 .writepages = btrfs_writepages, 10791 .readpages = btrfs_readpages, 10792 .direct_IO = btrfs_direct_IO, 10793 .invalidatepage = btrfs_invalidatepage, 10794 .releasepage = btrfs_releasepage, 10795 .set_page_dirty = btrfs_set_page_dirty, 10796 .error_remove_page = generic_error_remove_page, 10797 }; 10798 10799 static const struct address_space_operations btrfs_symlink_aops = { 10800 .readpage = btrfs_readpage, 10801 .writepage = btrfs_writepage, 10802 .invalidatepage = btrfs_invalidatepage, 10803 .releasepage = btrfs_releasepage, 10804 }; 10805 10806 static const struct inode_operations btrfs_file_inode_operations = { 10807 .getattr = btrfs_getattr, 10808 .setattr = btrfs_setattr, 10809 .listxattr = btrfs_listxattr, 10810 .permission = btrfs_permission, 10811 .fiemap = btrfs_fiemap, 10812 .get_acl = btrfs_get_acl, 10813 .set_acl = btrfs_set_acl, 10814 .update_time = btrfs_update_time, 10815 }; 10816 static const struct inode_operations btrfs_special_inode_operations = { 10817 .getattr = btrfs_getattr, 10818 .setattr = btrfs_setattr, 10819 .permission = btrfs_permission, 10820 .listxattr = btrfs_listxattr, 10821 .get_acl = btrfs_get_acl, 10822 .set_acl = btrfs_set_acl, 10823 .update_time = btrfs_update_time, 10824 }; 10825 static const struct inode_operations btrfs_symlink_inode_operations = { 10826 .get_link = page_get_link, 10827 .getattr = btrfs_getattr, 10828 .setattr = btrfs_setattr, 10829 .permission = btrfs_permission, 10830 .listxattr = btrfs_listxattr, 10831 .update_time = btrfs_update_time, 10832 }; 10833 10834 const struct dentry_operations btrfs_dentry_operations = { 10835 .d_delete = btrfs_dentry_delete, 10836 .d_release = btrfs_dentry_release, 10837 }; 10838