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/statfs.h> 34 #include <linux/compat.h> 35 #include <linux/bit_spinlock.h> 36 #include <linux/xattr.h> 37 #include <linux/posix_acl.h> 38 #include <linux/falloc.h> 39 #include <linux/slab.h> 40 #include <linux/ratelimit.h> 41 #include <linux/mount.h> 42 #include <linux/btrfs.h> 43 #include <linux/blkdev.h> 44 #include <linux/posix_acl_xattr.h> 45 #include <linux/uio.h> 46 #include "ctree.h" 47 #include "disk-io.h" 48 #include "transaction.h" 49 #include "btrfs_inode.h" 50 #include "print-tree.h" 51 #include "ordered-data.h" 52 #include "xattr.h" 53 #include "tree-log.h" 54 #include "volumes.h" 55 #include "compression.h" 56 #include "locking.h" 57 #include "free-space-cache.h" 58 #include "inode-map.h" 59 #include "backref.h" 60 #include "hash.h" 61 #include "props.h" 62 #include "qgroup.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 }; 75 76 static const struct inode_operations btrfs_dir_inode_operations; 77 static const struct inode_operations btrfs_symlink_inode_operations; 78 static const struct inode_operations btrfs_dir_ro_inode_operations; 79 static const struct inode_operations btrfs_special_inode_operations; 80 static const struct inode_operations btrfs_file_inode_operations; 81 static const struct address_space_operations btrfs_aops; 82 static const struct address_space_operations btrfs_symlink_aops; 83 static const struct file_operations btrfs_dir_file_operations; 84 static const struct extent_io_ops btrfs_extent_io_ops; 85 86 static struct kmem_cache *btrfs_inode_cachep; 87 struct kmem_cache *btrfs_trans_handle_cachep; 88 struct kmem_cache *btrfs_transaction_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, int *page_started, 109 unsigned long *nr_written, int unlock); 110 static struct extent_map *create_pinned_em(struct inode *inode, u64 start, 111 u64 len, u64 orig_start, 112 u64 block_start, u64 block_len, 113 u64 orig_block_len, u64 ram_bytes, 114 int type); 115 116 static int btrfs_dirty_inode(struct inode *inode); 117 118 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 119 void btrfs_test_inode_set_ops(struct inode *inode) 120 { 121 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 122 } 123 #endif 124 125 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, 126 struct inode *inode, struct inode *dir, 127 const struct qstr *qstr) 128 { 129 int err; 130 131 err = btrfs_init_acl(trans, inode, dir); 132 if (!err) 133 err = btrfs_xattr_security_init(trans, inode, dir, qstr); 134 return err; 135 } 136 137 /* 138 * this does all the hard work for inserting an inline extent into 139 * the btree. The caller should have done a btrfs_drop_extents so that 140 * no overlapping inline items exist in the btree 141 */ 142 static int insert_inline_extent(struct btrfs_trans_handle *trans, 143 struct btrfs_path *path, int extent_inserted, 144 struct btrfs_root *root, struct inode *inode, 145 u64 start, size_t size, size_t compressed_size, 146 int compress_type, 147 struct page **compressed_pages) 148 { 149 struct extent_buffer *leaf; 150 struct page *page = NULL; 151 char *kaddr; 152 unsigned long ptr; 153 struct btrfs_file_extent_item *ei; 154 int err = 0; 155 int ret; 156 size_t cur_size = size; 157 unsigned long offset; 158 159 if (compressed_size && compressed_pages) 160 cur_size = compressed_size; 161 162 inode_add_bytes(inode, size); 163 164 if (!extent_inserted) { 165 struct btrfs_key key; 166 size_t datasize; 167 168 key.objectid = btrfs_ino(inode); 169 key.offset = start; 170 key.type = BTRFS_EXTENT_DATA_KEY; 171 172 datasize = btrfs_file_extent_calc_inline_size(cur_size); 173 path->leave_spinning = 1; 174 ret = btrfs_insert_empty_item(trans, root, path, &key, 175 datasize); 176 if (ret) { 177 err = ret; 178 goto fail; 179 } 180 } 181 leaf = path->nodes[0]; 182 ei = btrfs_item_ptr(leaf, path->slots[0], 183 struct btrfs_file_extent_item); 184 btrfs_set_file_extent_generation(leaf, ei, trans->transid); 185 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); 186 btrfs_set_file_extent_encryption(leaf, ei, 0); 187 btrfs_set_file_extent_other_encoding(leaf, ei, 0); 188 btrfs_set_file_extent_ram_bytes(leaf, ei, size); 189 ptr = btrfs_file_extent_inline_start(ei); 190 191 if (compress_type != BTRFS_COMPRESS_NONE) { 192 struct page *cpage; 193 int i = 0; 194 while (compressed_size > 0) { 195 cpage = compressed_pages[i]; 196 cur_size = min_t(unsigned long, compressed_size, 197 PAGE_SIZE); 198 199 kaddr = kmap_atomic(cpage); 200 write_extent_buffer(leaf, kaddr, ptr, cur_size); 201 kunmap_atomic(kaddr); 202 203 i++; 204 ptr += cur_size; 205 compressed_size -= cur_size; 206 } 207 btrfs_set_file_extent_compression(leaf, ei, 208 compress_type); 209 } else { 210 page = find_get_page(inode->i_mapping, 211 start >> PAGE_SHIFT); 212 btrfs_set_file_extent_compression(leaf, ei, 0); 213 kaddr = kmap_atomic(page); 214 offset = start & (PAGE_SIZE - 1); 215 write_extent_buffer(leaf, kaddr + offset, ptr, size); 216 kunmap_atomic(kaddr); 217 put_page(page); 218 } 219 btrfs_mark_buffer_dirty(leaf); 220 btrfs_release_path(path); 221 222 /* 223 * we're an inline extent, so nobody can 224 * extend the file past i_size without locking 225 * a page we already have locked. 226 * 227 * We must do any isize and inode updates 228 * before we unlock the pages. Otherwise we 229 * could end up racing with unlink. 230 */ 231 BTRFS_I(inode)->disk_i_size = inode->i_size; 232 ret = btrfs_update_inode(trans, root, inode); 233 234 return ret; 235 fail: 236 return err; 237 } 238 239 240 /* 241 * conditionally insert an inline extent into the file. This 242 * does the checks required to make sure the data is small enough 243 * to fit as an inline extent. 244 */ 245 static noinline int cow_file_range_inline(struct btrfs_root *root, 246 struct inode *inode, u64 start, 247 u64 end, size_t compressed_size, 248 int compress_type, 249 struct page **compressed_pages) 250 { 251 struct btrfs_trans_handle *trans; 252 u64 isize = i_size_read(inode); 253 u64 actual_end = min(end + 1, isize); 254 u64 inline_len = actual_end - start; 255 u64 aligned_end = ALIGN(end, root->sectorsize); 256 u64 data_len = inline_len; 257 int ret; 258 struct btrfs_path *path; 259 int extent_inserted = 0; 260 u32 extent_item_size; 261 262 if (compressed_size) 263 data_len = compressed_size; 264 265 if (start > 0 || 266 actual_end > root->sectorsize || 267 data_len > BTRFS_MAX_INLINE_DATA_SIZE(root) || 268 (!compressed_size && 269 (actual_end & (root->sectorsize - 1)) == 0) || 270 end + 1 < isize || 271 data_len > root->fs_info->max_inline) { 272 return 1; 273 } 274 275 path = btrfs_alloc_path(); 276 if (!path) 277 return -ENOMEM; 278 279 trans = btrfs_join_transaction(root); 280 if (IS_ERR(trans)) { 281 btrfs_free_path(path); 282 return PTR_ERR(trans); 283 } 284 trans->block_rsv = &root->fs_info->delalloc_block_rsv; 285 286 if (compressed_size && compressed_pages) 287 extent_item_size = btrfs_file_extent_calc_inline_size( 288 compressed_size); 289 else 290 extent_item_size = btrfs_file_extent_calc_inline_size( 291 inline_len); 292 293 ret = __btrfs_drop_extents(trans, root, inode, path, 294 start, aligned_end, NULL, 295 1, 1, extent_item_size, &extent_inserted); 296 if (ret) { 297 btrfs_abort_transaction(trans, root, ret); 298 goto out; 299 } 300 301 if (isize > actual_end) 302 inline_len = min_t(u64, isize, actual_end); 303 ret = insert_inline_extent(trans, path, extent_inserted, 304 root, inode, start, 305 inline_len, compressed_size, 306 compress_type, compressed_pages); 307 if (ret && ret != -ENOSPC) { 308 btrfs_abort_transaction(trans, root, ret); 309 goto out; 310 } else if (ret == -ENOSPC) { 311 ret = 1; 312 goto out; 313 } 314 315 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 316 btrfs_delalloc_release_metadata(inode, end + 1 - start); 317 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0); 318 out: 319 /* 320 * Don't forget to free the reserved space, as for inlined extent 321 * it won't count as data extent, free them directly here. 322 * And at reserve time, it's always aligned to page size, so 323 * just free one page here. 324 */ 325 btrfs_qgroup_free_data(inode, 0, PAGE_SIZE); 326 btrfs_free_path(path); 327 btrfs_end_transaction(trans, root); 328 return ret; 329 } 330 331 struct async_extent { 332 u64 start; 333 u64 ram_size; 334 u64 compressed_size; 335 struct page **pages; 336 unsigned long nr_pages; 337 int compress_type; 338 struct list_head list; 339 }; 340 341 struct async_cow { 342 struct inode *inode; 343 struct btrfs_root *root; 344 struct page *locked_page; 345 u64 start; 346 u64 end; 347 struct list_head extents; 348 struct btrfs_work work; 349 }; 350 351 static noinline int add_async_extent(struct async_cow *cow, 352 u64 start, u64 ram_size, 353 u64 compressed_size, 354 struct page **pages, 355 unsigned long nr_pages, 356 int compress_type) 357 { 358 struct async_extent *async_extent; 359 360 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); 361 BUG_ON(!async_extent); /* -ENOMEM */ 362 async_extent->start = start; 363 async_extent->ram_size = ram_size; 364 async_extent->compressed_size = compressed_size; 365 async_extent->pages = pages; 366 async_extent->nr_pages = nr_pages; 367 async_extent->compress_type = compress_type; 368 list_add_tail(&async_extent->list, &cow->extents); 369 return 0; 370 } 371 372 static inline int inode_need_compress(struct inode *inode) 373 { 374 struct btrfs_root *root = BTRFS_I(inode)->root; 375 376 /* force compress */ 377 if (btrfs_test_opt(root, FORCE_COMPRESS)) 378 return 1; 379 /* bad compression ratios */ 380 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) 381 return 0; 382 if (btrfs_test_opt(root, COMPRESS) || 383 BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS || 384 BTRFS_I(inode)->force_compress) 385 return 1; 386 return 0; 387 } 388 389 /* 390 * we create compressed extents in two phases. The first 391 * phase compresses a range of pages that have already been 392 * locked (both pages and state bits are locked). 393 * 394 * This is done inside an ordered work queue, and the compression 395 * is spread across many cpus. The actual IO submission is step 396 * two, and the ordered work queue takes care of making sure that 397 * happens in the same order things were put onto the queue by 398 * writepages and friends. 399 * 400 * If this code finds it can't get good compression, it puts an 401 * entry onto the work queue to write the uncompressed bytes. This 402 * makes sure that both compressed inodes and uncompressed inodes 403 * are written in the same order that the flusher thread sent them 404 * down. 405 */ 406 static noinline void compress_file_range(struct inode *inode, 407 struct page *locked_page, 408 u64 start, u64 end, 409 struct async_cow *async_cow, 410 int *num_added) 411 { 412 struct btrfs_root *root = BTRFS_I(inode)->root; 413 u64 num_bytes; 414 u64 blocksize = root->sectorsize; 415 u64 actual_end; 416 u64 isize = i_size_read(inode); 417 int ret = 0; 418 struct page **pages = NULL; 419 unsigned long nr_pages; 420 unsigned long nr_pages_ret = 0; 421 unsigned long total_compressed = 0; 422 unsigned long total_in = 0; 423 unsigned long max_compressed = SZ_128K; 424 unsigned long max_uncompressed = SZ_128K; 425 int i; 426 int will_compress; 427 int compress_type = root->fs_info->compress_type; 428 int redirty = 0; 429 430 /* if this is a small write inside eof, kick off a defrag */ 431 if ((end - start + 1) < SZ_16K && 432 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) 433 btrfs_add_inode_defrag(NULL, inode); 434 435 actual_end = min_t(u64, isize, end + 1); 436 again: 437 will_compress = 0; 438 nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; 439 nr_pages = min_t(unsigned long, nr_pages, SZ_128K / PAGE_SIZE); 440 441 /* 442 * we don't want to send crud past the end of i_size through 443 * compression, that's just a waste of CPU time. So, if the 444 * end of the file is before the start of our current 445 * requested range of bytes, we bail out to the uncompressed 446 * cleanup code that can deal with all of this. 447 * 448 * It isn't really the fastest way to fix things, but this is a 449 * very uncommon corner. 450 */ 451 if (actual_end <= start) 452 goto cleanup_and_bail_uncompressed; 453 454 total_compressed = actual_end - start; 455 456 /* 457 * skip compression for a small file range(<=blocksize) that 458 * isn't an inline extent, since it doesn't save disk space at all. 459 */ 460 if (total_compressed <= blocksize && 461 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) 462 goto cleanup_and_bail_uncompressed; 463 464 /* we want to make sure that amount of ram required to uncompress 465 * an extent is reasonable, so we limit the total size in ram 466 * of a compressed extent to 128k. This is a crucial number 467 * because it also controls how easily we can spread reads across 468 * cpus for decompression. 469 * 470 * We also want to make sure the amount of IO required to do 471 * a random read is reasonably small, so we limit the size of 472 * a compressed extent to 128k. 473 */ 474 total_compressed = min(total_compressed, max_uncompressed); 475 num_bytes = ALIGN(end - start + 1, blocksize); 476 num_bytes = max(blocksize, num_bytes); 477 total_in = 0; 478 ret = 0; 479 480 /* 481 * we do compression for mount -o compress and when the 482 * inode has not been flagged as nocompress. This flag can 483 * change at any time if we discover bad compression ratios. 484 */ 485 if (inode_need_compress(inode)) { 486 WARN_ON(pages); 487 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); 488 if (!pages) { 489 /* just bail out to the uncompressed code */ 490 goto cont; 491 } 492 493 if (BTRFS_I(inode)->force_compress) 494 compress_type = BTRFS_I(inode)->force_compress; 495 496 /* 497 * we need to call clear_page_dirty_for_io on each 498 * page in the range. Otherwise applications with the file 499 * mmap'd can wander in and change the page contents while 500 * we are compressing them. 501 * 502 * If the compression fails for any reason, we set the pages 503 * dirty again later on. 504 */ 505 extent_range_clear_dirty_for_io(inode, start, end); 506 redirty = 1; 507 ret = btrfs_compress_pages(compress_type, 508 inode->i_mapping, start, 509 total_compressed, pages, 510 nr_pages, &nr_pages_ret, 511 &total_in, 512 &total_compressed, 513 max_compressed); 514 515 if (!ret) { 516 unsigned long offset = total_compressed & 517 (PAGE_SIZE - 1); 518 struct page *page = pages[nr_pages_ret - 1]; 519 char *kaddr; 520 521 /* zero the tail end of the last page, we might be 522 * sending it down to disk 523 */ 524 if (offset) { 525 kaddr = kmap_atomic(page); 526 memset(kaddr + offset, 0, 527 PAGE_SIZE - offset); 528 kunmap_atomic(kaddr); 529 } 530 will_compress = 1; 531 } 532 } 533 cont: 534 if (start == 0) { 535 /* lets try to make an inline extent */ 536 if (ret || total_in < (actual_end - start)) { 537 /* we didn't compress the entire range, try 538 * to make an uncompressed inline extent. 539 */ 540 ret = cow_file_range_inline(root, inode, start, end, 541 0, 0, NULL); 542 } else { 543 /* try making a compressed inline extent */ 544 ret = cow_file_range_inline(root, inode, start, end, 545 total_compressed, 546 compress_type, pages); 547 } 548 if (ret <= 0) { 549 unsigned long clear_flags = EXTENT_DELALLOC | 550 EXTENT_DEFRAG; 551 unsigned long page_error_op; 552 553 clear_flags |= (ret < 0) ? EXTENT_DO_ACCOUNTING : 0; 554 page_error_op = ret < 0 ? PAGE_SET_ERROR : 0; 555 556 /* 557 * inline extent creation worked or returned error, 558 * we don't need to create any more async work items. 559 * Unlock and free up our temp pages. 560 */ 561 extent_clear_unlock_delalloc(inode, start, end, NULL, 562 clear_flags, PAGE_UNLOCK | 563 PAGE_CLEAR_DIRTY | 564 PAGE_SET_WRITEBACK | 565 page_error_op | 566 PAGE_END_WRITEBACK); 567 goto free_pages_out; 568 } 569 } 570 571 if (will_compress) { 572 /* 573 * we aren't doing an inline extent round the compressed size 574 * up to a block size boundary so the allocator does sane 575 * things 576 */ 577 total_compressed = ALIGN(total_compressed, blocksize); 578 579 /* 580 * one last check to make sure the compression is really a 581 * win, compare the page count read with the blocks on disk 582 */ 583 total_in = ALIGN(total_in, PAGE_SIZE); 584 if (total_compressed >= total_in) { 585 will_compress = 0; 586 } else { 587 num_bytes = total_in; 588 } 589 } 590 if (!will_compress && pages) { 591 /* 592 * the compression code ran but failed to make things smaller, 593 * free any pages it allocated and our page pointer array 594 */ 595 for (i = 0; i < nr_pages_ret; i++) { 596 WARN_ON(pages[i]->mapping); 597 put_page(pages[i]); 598 } 599 kfree(pages); 600 pages = NULL; 601 total_compressed = 0; 602 nr_pages_ret = 0; 603 604 /* flag the file so we don't compress in the future */ 605 if (!btrfs_test_opt(root, FORCE_COMPRESS) && 606 !(BTRFS_I(inode)->force_compress)) { 607 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; 608 } 609 } 610 if (will_compress) { 611 *num_added += 1; 612 613 /* the async work queues will take care of doing actual 614 * allocation on disk for these compressed pages, 615 * and will submit them to the elevator. 616 */ 617 add_async_extent(async_cow, start, num_bytes, 618 total_compressed, pages, nr_pages_ret, 619 compress_type); 620 621 if (start + num_bytes < end) { 622 start += num_bytes; 623 pages = NULL; 624 cond_resched(); 625 goto again; 626 } 627 } else { 628 cleanup_and_bail_uncompressed: 629 /* 630 * No compression, but we still need to write the pages in 631 * the file we've been given so far. redirty the locked 632 * page if it corresponds to our extent and set things up 633 * for the async work queue to run cow_file_range to do 634 * the normal delalloc dance 635 */ 636 if (page_offset(locked_page) >= start && 637 page_offset(locked_page) <= end) { 638 __set_page_dirty_nobuffers(locked_page); 639 /* unlocked later on in the async handlers */ 640 } 641 if (redirty) 642 extent_range_redirty_for_io(inode, start, end); 643 add_async_extent(async_cow, start, end - start + 1, 644 0, NULL, 0, BTRFS_COMPRESS_NONE); 645 *num_added += 1; 646 } 647 648 return; 649 650 free_pages_out: 651 for (i = 0; i < nr_pages_ret; i++) { 652 WARN_ON(pages[i]->mapping); 653 put_page(pages[i]); 654 } 655 kfree(pages); 656 } 657 658 static void free_async_extent_pages(struct async_extent *async_extent) 659 { 660 int i; 661 662 if (!async_extent->pages) 663 return; 664 665 for (i = 0; i < async_extent->nr_pages; i++) { 666 WARN_ON(async_extent->pages[i]->mapping); 667 put_page(async_extent->pages[i]); 668 } 669 kfree(async_extent->pages); 670 async_extent->nr_pages = 0; 671 async_extent->pages = NULL; 672 } 673 674 /* 675 * phase two of compressed writeback. This is the ordered portion 676 * of the code, which only gets called in the order the work was 677 * queued. We walk all the async extents created by compress_file_range 678 * and send them down to the disk. 679 */ 680 static noinline void submit_compressed_extents(struct inode *inode, 681 struct async_cow *async_cow) 682 { 683 struct async_extent *async_extent; 684 u64 alloc_hint = 0; 685 struct btrfs_key ins; 686 struct extent_map *em; 687 struct btrfs_root *root = BTRFS_I(inode)->root; 688 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 689 struct extent_io_tree *io_tree; 690 int ret = 0; 691 692 again: 693 while (!list_empty(&async_cow->extents)) { 694 async_extent = list_entry(async_cow->extents.next, 695 struct async_extent, list); 696 list_del(&async_extent->list); 697 698 io_tree = &BTRFS_I(inode)->io_tree; 699 700 retry: 701 /* did the compression code fall back to uncompressed IO? */ 702 if (!async_extent->pages) { 703 int page_started = 0; 704 unsigned long nr_written = 0; 705 706 lock_extent(io_tree, async_extent->start, 707 async_extent->start + 708 async_extent->ram_size - 1); 709 710 /* allocate blocks */ 711 ret = cow_file_range(inode, async_cow->locked_page, 712 async_extent->start, 713 async_extent->start + 714 async_extent->ram_size - 1, 715 &page_started, &nr_written, 0); 716 717 /* JDM XXX */ 718 719 /* 720 * if page_started, cow_file_range inserted an 721 * inline extent and took care of all the unlocking 722 * and IO for us. Otherwise, we need to submit 723 * all those pages down to the drive. 724 */ 725 if (!page_started && !ret) 726 extent_write_locked_range(io_tree, 727 inode, async_extent->start, 728 async_extent->start + 729 async_extent->ram_size - 1, 730 btrfs_get_extent, 731 WB_SYNC_ALL); 732 else if (ret) 733 unlock_page(async_cow->locked_page); 734 kfree(async_extent); 735 cond_resched(); 736 continue; 737 } 738 739 lock_extent(io_tree, async_extent->start, 740 async_extent->start + async_extent->ram_size - 1); 741 742 ret = btrfs_reserve_extent(root, 743 async_extent->compressed_size, 744 async_extent->compressed_size, 745 0, alloc_hint, &ins, 1, 1); 746 if (ret) { 747 free_async_extent_pages(async_extent); 748 749 if (ret == -ENOSPC) { 750 unlock_extent(io_tree, async_extent->start, 751 async_extent->start + 752 async_extent->ram_size - 1); 753 754 /* 755 * we need to redirty the pages if we decide to 756 * fallback to uncompressed IO, otherwise we 757 * will not submit these pages down to lower 758 * layers. 759 */ 760 extent_range_redirty_for_io(inode, 761 async_extent->start, 762 async_extent->start + 763 async_extent->ram_size - 1); 764 765 goto retry; 766 } 767 goto out_free; 768 } 769 /* 770 * here we're doing allocation and writeback of the 771 * compressed pages 772 */ 773 btrfs_drop_extent_cache(inode, async_extent->start, 774 async_extent->start + 775 async_extent->ram_size - 1, 0); 776 777 em = alloc_extent_map(); 778 if (!em) { 779 ret = -ENOMEM; 780 goto out_free_reserve; 781 } 782 em->start = async_extent->start; 783 em->len = async_extent->ram_size; 784 em->orig_start = em->start; 785 em->mod_start = em->start; 786 em->mod_len = em->len; 787 788 em->block_start = ins.objectid; 789 em->block_len = ins.offset; 790 em->orig_block_len = ins.offset; 791 em->ram_bytes = async_extent->ram_size; 792 em->bdev = root->fs_info->fs_devices->latest_bdev; 793 em->compress_type = async_extent->compress_type; 794 set_bit(EXTENT_FLAG_PINNED, &em->flags); 795 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); 796 em->generation = -1; 797 798 while (1) { 799 write_lock(&em_tree->lock); 800 ret = add_extent_mapping(em_tree, em, 1); 801 write_unlock(&em_tree->lock); 802 if (ret != -EEXIST) { 803 free_extent_map(em); 804 break; 805 } 806 btrfs_drop_extent_cache(inode, async_extent->start, 807 async_extent->start + 808 async_extent->ram_size - 1, 0); 809 } 810 811 if (ret) 812 goto out_free_reserve; 813 814 ret = btrfs_add_ordered_extent_compress(inode, 815 async_extent->start, 816 ins.objectid, 817 async_extent->ram_size, 818 ins.offset, 819 BTRFS_ORDERED_COMPRESSED, 820 async_extent->compress_type); 821 if (ret) { 822 btrfs_drop_extent_cache(inode, async_extent->start, 823 async_extent->start + 824 async_extent->ram_size - 1, 0); 825 goto out_free_reserve; 826 } 827 btrfs_dec_block_group_reservations(root->fs_info, ins.objectid); 828 829 /* 830 * clear dirty, set writeback and unlock the pages. 831 */ 832 extent_clear_unlock_delalloc(inode, async_extent->start, 833 async_extent->start + 834 async_extent->ram_size - 1, 835 NULL, EXTENT_LOCKED | EXTENT_DELALLOC, 836 PAGE_UNLOCK | PAGE_CLEAR_DIRTY | 837 PAGE_SET_WRITEBACK); 838 ret = btrfs_submit_compressed_write(inode, 839 async_extent->start, 840 async_extent->ram_size, 841 ins.objectid, 842 ins.offset, async_extent->pages, 843 async_extent->nr_pages); 844 if (ret) { 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, NULL, 0, 855 PAGE_END_WRITEBACK | 856 PAGE_SET_ERROR); 857 free_async_extent_pages(async_extent); 858 } 859 alloc_hint = ins.objectid + ins.offset; 860 kfree(async_extent); 861 cond_resched(); 862 } 863 return; 864 out_free_reserve: 865 btrfs_dec_block_group_reservations(root->fs_info, ins.objectid); 866 btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1); 867 out_free: 868 extent_clear_unlock_delalloc(inode, async_extent->start, 869 async_extent->start + 870 async_extent->ram_size - 1, 871 NULL, EXTENT_LOCKED | EXTENT_DELALLOC | 872 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, 873 PAGE_UNLOCK | PAGE_CLEAR_DIRTY | 874 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK | 875 PAGE_SET_ERROR); 876 free_async_extent_pages(async_extent); 877 kfree(async_extent); 878 goto again; 879 } 880 881 static u64 get_extent_allocation_hint(struct inode *inode, u64 start, 882 u64 num_bytes) 883 { 884 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 885 struct extent_map *em; 886 u64 alloc_hint = 0; 887 888 read_lock(&em_tree->lock); 889 em = search_extent_mapping(em_tree, start, num_bytes); 890 if (em) { 891 /* 892 * if block start isn't an actual block number then find the 893 * first block in this inode and use that as a hint. If that 894 * block is also bogus then just don't worry about it. 895 */ 896 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 897 free_extent_map(em); 898 em = search_extent_mapping(em_tree, 0, 0); 899 if (em && em->block_start < EXTENT_MAP_LAST_BYTE) 900 alloc_hint = em->block_start; 901 if (em) 902 free_extent_map(em); 903 } else { 904 alloc_hint = em->block_start; 905 free_extent_map(em); 906 } 907 } 908 read_unlock(&em_tree->lock); 909 910 return alloc_hint; 911 } 912 913 /* 914 * when extent_io.c finds a delayed allocation range in the file, 915 * the call backs end up in this code. The basic idea is to 916 * allocate extents on disk for the range, and create ordered data structs 917 * in ram to track those extents. 918 * 919 * locked_page is the page that writepage had locked already. We use 920 * it to make sure we don't do extra locks or unlocks. 921 * 922 * *page_started is set to one if we unlock locked_page and do everything 923 * required to start IO on it. It may be clean and already done with 924 * IO when we return. 925 */ 926 static noinline int cow_file_range(struct inode *inode, 927 struct page *locked_page, 928 u64 start, u64 end, int *page_started, 929 unsigned long *nr_written, 930 int unlock) 931 { 932 struct btrfs_root *root = BTRFS_I(inode)->root; 933 u64 alloc_hint = 0; 934 u64 num_bytes; 935 unsigned long ram_size; 936 u64 disk_num_bytes; 937 u64 cur_alloc_size; 938 u64 blocksize = root->sectorsize; 939 struct btrfs_key ins; 940 struct extent_map *em; 941 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 942 int ret = 0; 943 944 if (btrfs_is_free_space_inode(inode)) { 945 WARN_ON_ONCE(1); 946 ret = -EINVAL; 947 goto out_unlock; 948 } 949 950 num_bytes = ALIGN(end - start + 1, blocksize); 951 num_bytes = max(blocksize, num_bytes); 952 disk_num_bytes = num_bytes; 953 954 /* if this is a small write inside eof, kick off defrag */ 955 if (num_bytes < SZ_64K && 956 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) 957 btrfs_add_inode_defrag(NULL, inode); 958 959 if (start == 0) { 960 /* lets try to make an inline extent */ 961 ret = cow_file_range_inline(root, inode, start, end, 0, 0, 962 NULL); 963 if (ret == 0) { 964 extent_clear_unlock_delalloc(inode, start, end, NULL, 965 EXTENT_LOCKED | EXTENT_DELALLOC | 966 EXTENT_DEFRAG, PAGE_UNLOCK | 967 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | 968 PAGE_END_WRITEBACK); 969 970 *nr_written = *nr_written + 971 (end - start + PAGE_SIZE) / PAGE_SIZE; 972 *page_started = 1; 973 goto out; 974 } else if (ret < 0) { 975 goto out_unlock; 976 } 977 } 978 979 BUG_ON(disk_num_bytes > 980 btrfs_super_total_bytes(root->fs_info->super_copy)); 981 982 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); 983 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); 984 985 while (disk_num_bytes > 0) { 986 unsigned long op; 987 988 cur_alloc_size = disk_num_bytes; 989 ret = btrfs_reserve_extent(root, cur_alloc_size, 990 root->sectorsize, 0, alloc_hint, 991 &ins, 1, 1); 992 if (ret < 0) 993 goto out_unlock; 994 995 em = alloc_extent_map(); 996 if (!em) { 997 ret = -ENOMEM; 998 goto out_reserve; 999 } 1000 em->start = start; 1001 em->orig_start = em->start; 1002 ram_size = ins.offset; 1003 em->len = ins.offset; 1004 em->mod_start = em->start; 1005 em->mod_len = em->len; 1006 1007 em->block_start = ins.objectid; 1008 em->block_len = ins.offset; 1009 em->orig_block_len = ins.offset; 1010 em->ram_bytes = ram_size; 1011 em->bdev = root->fs_info->fs_devices->latest_bdev; 1012 set_bit(EXTENT_FLAG_PINNED, &em->flags); 1013 em->generation = -1; 1014 1015 while (1) { 1016 write_lock(&em_tree->lock); 1017 ret = add_extent_mapping(em_tree, em, 1); 1018 write_unlock(&em_tree->lock); 1019 if (ret != -EEXIST) { 1020 free_extent_map(em); 1021 break; 1022 } 1023 btrfs_drop_extent_cache(inode, start, 1024 start + ram_size - 1, 0); 1025 } 1026 if (ret) 1027 goto out_reserve; 1028 1029 cur_alloc_size = ins.offset; 1030 ret = btrfs_add_ordered_extent(inode, start, ins.objectid, 1031 ram_size, cur_alloc_size, 0); 1032 if (ret) 1033 goto out_drop_extent_cache; 1034 1035 if (root->root_key.objectid == 1036 BTRFS_DATA_RELOC_TREE_OBJECTID) { 1037 ret = btrfs_reloc_clone_csums(inode, start, 1038 cur_alloc_size); 1039 if (ret) 1040 goto out_drop_extent_cache; 1041 } 1042 1043 btrfs_dec_block_group_reservations(root->fs_info, ins.objectid); 1044 1045 if (disk_num_bytes < cur_alloc_size) 1046 break; 1047 1048 /* we're not doing compressed IO, don't unlock the first 1049 * page (which the caller expects to stay locked), don't 1050 * clear any dirty bits and don't set any writeback bits 1051 * 1052 * Do set the Private2 bit so we know this page was properly 1053 * setup for writepage 1054 */ 1055 op = unlock ? PAGE_UNLOCK : 0; 1056 op |= PAGE_SET_PRIVATE2; 1057 1058 extent_clear_unlock_delalloc(inode, start, 1059 start + ram_size - 1, locked_page, 1060 EXTENT_LOCKED | EXTENT_DELALLOC, 1061 op); 1062 disk_num_bytes -= cur_alloc_size; 1063 num_bytes -= cur_alloc_size; 1064 alloc_hint = ins.objectid + ins.offset; 1065 start += cur_alloc_size; 1066 } 1067 out: 1068 return ret; 1069 1070 out_drop_extent_cache: 1071 btrfs_drop_extent_cache(inode, start, start + ram_size - 1, 0); 1072 out_reserve: 1073 btrfs_dec_block_group_reservations(root->fs_info, ins.objectid); 1074 btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1); 1075 out_unlock: 1076 extent_clear_unlock_delalloc(inode, start, end, locked_page, 1077 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING | 1078 EXTENT_DELALLOC | EXTENT_DEFRAG, 1079 PAGE_UNLOCK | PAGE_CLEAR_DIRTY | 1080 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK); 1081 goto out; 1082 } 1083 1084 /* 1085 * work queue call back to started compression on a file and pages 1086 */ 1087 static noinline void async_cow_start(struct btrfs_work *work) 1088 { 1089 struct async_cow *async_cow; 1090 int num_added = 0; 1091 async_cow = container_of(work, struct async_cow, work); 1092 1093 compress_file_range(async_cow->inode, async_cow->locked_page, 1094 async_cow->start, async_cow->end, async_cow, 1095 &num_added); 1096 if (num_added == 0) { 1097 btrfs_add_delayed_iput(async_cow->inode); 1098 async_cow->inode = NULL; 1099 } 1100 } 1101 1102 /* 1103 * work queue call back to submit previously compressed pages 1104 */ 1105 static noinline void async_cow_submit(struct btrfs_work *work) 1106 { 1107 struct async_cow *async_cow; 1108 struct btrfs_root *root; 1109 unsigned long nr_pages; 1110 1111 async_cow = container_of(work, struct async_cow, work); 1112 1113 root = async_cow->root; 1114 nr_pages = (async_cow->end - async_cow->start + PAGE_SIZE) >> 1115 PAGE_SHIFT; 1116 1117 /* 1118 * atomic_sub_return implies a barrier for waitqueue_active 1119 */ 1120 if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) < 1121 5 * SZ_1M && 1122 waitqueue_active(&root->fs_info->async_submit_wait)) 1123 wake_up(&root->fs_info->async_submit_wait); 1124 1125 if (async_cow->inode) 1126 submit_compressed_extents(async_cow->inode, async_cow); 1127 } 1128 1129 static noinline void async_cow_free(struct btrfs_work *work) 1130 { 1131 struct async_cow *async_cow; 1132 async_cow = container_of(work, struct async_cow, work); 1133 if (async_cow->inode) 1134 btrfs_add_delayed_iput(async_cow->inode); 1135 kfree(async_cow); 1136 } 1137 1138 static int cow_file_range_async(struct inode *inode, struct page *locked_page, 1139 u64 start, u64 end, int *page_started, 1140 unsigned long *nr_written) 1141 { 1142 struct async_cow *async_cow; 1143 struct btrfs_root *root = BTRFS_I(inode)->root; 1144 unsigned long nr_pages; 1145 u64 cur_end; 1146 int limit = 10 * SZ_1M; 1147 1148 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED, 1149 1, 0, NULL, GFP_NOFS); 1150 while (start < end) { 1151 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); 1152 BUG_ON(!async_cow); /* -ENOMEM */ 1153 async_cow->inode = igrab(inode); 1154 async_cow->root = root; 1155 async_cow->locked_page = locked_page; 1156 async_cow->start = start; 1157 1158 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS && 1159 !btrfs_test_opt(root, FORCE_COMPRESS)) 1160 cur_end = end; 1161 else 1162 cur_end = min(end, start + SZ_512K - 1); 1163 1164 async_cow->end = cur_end; 1165 INIT_LIST_HEAD(&async_cow->extents); 1166 1167 btrfs_init_work(&async_cow->work, 1168 btrfs_delalloc_helper, 1169 async_cow_start, async_cow_submit, 1170 async_cow_free); 1171 1172 nr_pages = (cur_end - start + PAGE_SIZE) >> 1173 PAGE_SHIFT; 1174 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages); 1175 1176 btrfs_queue_work(root->fs_info->delalloc_workers, 1177 &async_cow->work); 1178 1179 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) { 1180 wait_event(root->fs_info->async_submit_wait, 1181 (atomic_read(&root->fs_info->async_delalloc_pages) < 1182 limit)); 1183 } 1184 1185 while (atomic_read(&root->fs_info->async_submit_draining) && 1186 atomic_read(&root->fs_info->async_delalloc_pages)) { 1187 wait_event(root->fs_info->async_submit_wait, 1188 (atomic_read(&root->fs_info->async_delalloc_pages) == 1189 0)); 1190 } 1191 1192 *nr_written += nr_pages; 1193 start = cur_end + 1; 1194 } 1195 *page_started = 1; 1196 return 0; 1197 } 1198 1199 static noinline int csum_exist_in_range(struct btrfs_root *root, 1200 u64 bytenr, u64 num_bytes) 1201 { 1202 int ret; 1203 struct btrfs_ordered_sum *sums; 1204 LIST_HEAD(list); 1205 1206 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr, 1207 bytenr + num_bytes - 1, &list, 0); 1208 if (ret == 0 && list_empty(&list)) 1209 return 0; 1210 1211 while (!list_empty(&list)) { 1212 sums = list_entry(list.next, struct btrfs_ordered_sum, list); 1213 list_del(&sums->list); 1214 kfree(sums); 1215 } 1216 return 1; 1217 } 1218 1219 /* 1220 * when nowcow writeback call back. This checks for snapshots or COW copies 1221 * of the extents that exist in the file, and COWs the file as required. 1222 * 1223 * If no cow copies or snapshots exist, we write directly to the existing 1224 * blocks on disk 1225 */ 1226 static noinline int run_delalloc_nocow(struct inode *inode, 1227 struct page *locked_page, 1228 u64 start, u64 end, int *page_started, int force, 1229 unsigned long *nr_written) 1230 { 1231 struct btrfs_root *root = BTRFS_I(inode)->root; 1232 struct btrfs_trans_handle *trans; 1233 struct extent_buffer *leaf; 1234 struct btrfs_path *path; 1235 struct btrfs_file_extent_item *fi; 1236 struct btrfs_key found_key; 1237 u64 cow_start; 1238 u64 cur_offset; 1239 u64 extent_end; 1240 u64 extent_offset; 1241 u64 disk_bytenr; 1242 u64 num_bytes; 1243 u64 disk_num_bytes; 1244 u64 ram_bytes; 1245 int extent_type; 1246 int ret, err; 1247 int type; 1248 int nocow; 1249 int check_prev = 1; 1250 bool nolock; 1251 u64 ino = btrfs_ino(inode); 1252 1253 path = btrfs_alloc_path(); 1254 if (!path) { 1255 extent_clear_unlock_delalloc(inode, start, end, locked_page, 1256 EXTENT_LOCKED | EXTENT_DELALLOC | 1257 EXTENT_DO_ACCOUNTING | 1258 EXTENT_DEFRAG, PAGE_UNLOCK | 1259 PAGE_CLEAR_DIRTY | 1260 PAGE_SET_WRITEBACK | 1261 PAGE_END_WRITEBACK); 1262 return -ENOMEM; 1263 } 1264 1265 nolock = btrfs_is_free_space_inode(inode); 1266 1267 if (nolock) 1268 trans = btrfs_join_transaction_nolock(root); 1269 else 1270 trans = btrfs_join_transaction(root); 1271 1272 if (IS_ERR(trans)) { 1273 extent_clear_unlock_delalloc(inode, start, end, locked_page, 1274 EXTENT_LOCKED | EXTENT_DELALLOC | 1275 EXTENT_DO_ACCOUNTING | 1276 EXTENT_DEFRAG, PAGE_UNLOCK | 1277 PAGE_CLEAR_DIRTY | 1278 PAGE_SET_WRITEBACK | 1279 PAGE_END_WRITEBACK); 1280 btrfs_free_path(path); 1281 return PTR_ERR(trans); 1282 } 1283 1284 trans->block_rsv = &root->fs_info->delalloc_block_rsv; 1285 1286 cow_start = (u64)-1; 1287 cur_offset = start; 1288 while (1) { 1289 ret = btrfs_lookup_file_extent(trans, root, path, ino, 1290 cur_offset, 0); 1291 if (ret < 0) 1292 goto error; 1293 if (ret > 0 && path->slots[0] > 0 && check_prev) { 1294 leaf = path->nodes[0]; 1295 btrfs_item_key_to_cpu(leaf, &found_key, 1296 path->slots[0] - 1); 1297 if (found_key.objectid == ino && 1298 found_key.type == BTRFS_EXTENT_DATA_KEY) 1299 path->slots[0]--; 1300 } 1301 check_prev = 0; 1302 next_slot: 1303 leaf = path->nodes[0]; 1304 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1305 ret = btrfs_next_leaf(root, path); 1306 if (ret < 0) 1307 goto error; 1308 if (ret > 0) 1309 break; 1310 leaf = path->nodes[0]; 1311 } 1312 1313 nocow = 0; 1314 disk_bytenr = 0; 1315 num_bytes = 0; 1316 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1317 1318 if (found_key.objectid > ino) 1319 break; 1320 if (WARN_ON_ONCE(found_key.objectid < ino) || 1321 found_key.type < BTRFS_EXTENT_DATA_KEY) { 1322 path->slots[0]++; 1323 goto next_slot; 1324 } 1325 if (found_key.type > BTRFS_EXTENT_DATA_KEY || 1326 found_key.offset > end) 1327 break; 1328 1329 if (found_key.offset > cur_offset) { 1330 extent_end = found_key.offset; 1331 extent_type = 0; 1332 goto out_check; 1333 } 1334 1335 fi = btrfs_item_ptr(leaf, path->slots[0], 1336 struct btrfs_file_extent_item); 1337 extent_type = btrfs_file_extent_type(leaf, fi); 1338 1339 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); 1340 if (extent_type == BTRFS_FILE_EXTENT_REG || 1341 extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1342 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 1343 extent_offset = btrfs_file_extent_offset(leaf, fi); 1344 extent_end = found_key.offset + 1345 btrfs_file_extent_num_bytes(leaf, fi); 1346 disk_num_bytes = 1347 btrfs_file_extent_disk_num_bytes(leaf, fi); 1348 if (extent_end <= start) { 1349 path->slots[0]++; 1350 goto next_slot; 1351 } 1352 if (disk_bytenr == 0) 1353 goto out_check; 1354 if (btrfs_file_extent_compression(leaf, fi) || 1355 btrfs_file_extent_encryption(leaf, fi) || 1356 btrfs_file_extent_other_encoding(leaf, fi)) 1357 goto out_check; 1358 if (extent_type == BTRFS_FILE_EXTENT_REG && !force) 1359 goto out_check; 1360 if (btrfs_extent_readonly(root, disk_bytenr)) 1361 goto out_check; 1362 if (btrfs_cross_ref_exist(trans, root, ino, 1363 found_key.offset - 1364 extent_offset, disk_bytenr)) 1365 goto out_check; 1366 disk_bytenr += extent_offset; 1367 disk_bytenr += cur_offset - found_key.offset; 1368 num_bytes = min(end + 1, extent_end) - cur_offset; 1369 /* 1370 * if there are pending snapshots for this root, 1371 * we fall into common COW way. 1372 */ 1373 if (!nolock) { 1374 err = btrfs_start_write_no_snapshoting(root); 1375 if (!err) 1376 goto out_check; 1377 } 1378 /* 1379 * force cow if csum exists in the range. 1380 * this ensure that csum for a given extent are 1381 * either valid or do not exist. 1382 */ 1383 if (csum_exist_in_range(root, disk_bytenr, num_bytes)) 1384 goto out_check; 1385 if (!btrfs_inc_nocow_writers(root->fs_info, 1386 disk_bytenr)) 1387 goto out_check; 1388 nocow = 1; 1389 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 1390 extent_end = found_key.offset + 1391 btrfs_file_extent_inline_len(leaf, 1392 path->slots[0], fi); 1393 extent_end = ALIGN(extent_end, root->sectorsize); 1394 } else { 1395 BUG_ON(1); 1396 } 1397 out_check: 1398 if (extent_end <= start) { 1399 path->slots[0]++; 1400 if (!nolock && nocow) 1401 btrfs_end_write_no_snapshoting(root); 1402 if (nocow) 1403 btrfs_dec_nocow_writers(root->fs_info, 1404 disk_bytenr); 1405 goto next_slot; 1406 } 1407 if (!nocow) { 1408 if (cow_start == (u64)-1) 1409 cow_start = cur_offset; 1410 cur_offset = extent_end; 1411 if (cur_offset > end) 1412 break; 1413 path->slots[0]++; 1414 goto next_slot; 1415 } 1416 1417 btrfs_release_path(path); 1418 if (cow_start != (u64)-1) { 1419 ret = cow_file_range(inode, locked_page, 1420 cow_start, found_key.offset - 1, 1421 page_started, nr_written, 1); 1422 if (ret) { 1423 if (!nolock && nocow) 1424 btrfs_end_write_no_snapshoting(root); 1425 if (nocow) 1426 btrfs_dec_nocow_writers(root->fs_info, 1427 disk_bytenr); 1428 goto error; 1429 } 1430 cow_start = (u64)-1; 1431 } 1432 1433 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1434 struct extent_map *em; 1435 struct extent_map_tree *em_tree; 1436 em_tree = &BTRFS_I(inode)->extent_tree; 1437 em = alloc_extent_map(); 1438 BUG_ON(!em); /* -ENOMEM */ 1439 em->start = cur_offset; 1440 em->orig_start = found_key.offset - extent_offset; 1441 em->len = num_bytes; 1442 em->block_len = num_bytes; 1443 em->block_start = disk_bytenr; 1444 em->orig_block_len = disk_num_bytes; 1445 em->ram_bytes = ram_bytes; 1446 em->bdev = root->fs_info->fs_devices->latest_bdev; 1447 em->mod_start = em->start; 1448 em->mod_len = em->len; 1449 set_bit(EXTENT_FLAG_PINNED, &em->flags); 1450 set_bit(EXTENT_FLAG_FILLING, &em->flags); 1451 em->generation = -1; 1452 while (1) { 1453 write_lock(&em_tree->lock); 1454 ret = add_extent_mapping(em_tree, em, 1); 1455 write_unlock(&em_tree->lock); 1456 if (ret != -EEXIST) { 1457 free_extent_map(em); 1458 break; 1459 } 1460 btrfs_drop_extent_cache(inode, em->start, 1461 em->start + em->len - 1, 0); 1462 } 1463 type = BTRFS_ORDERED_PREALLOC; 1464 } else { 1465 type = BTRFS_ORDERED_NOCOW; 1466 } 1467 1468 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr, 1469 num_bytes, num_bytes, type); 1470 if (nocow) 1471 btrfs_dec_nocow_writers(root->fs_info, disk_bytenr); 1472 BUG_ON(ret); /* -ENOMEM */ 1473 1474 if (root->root_key.objectid == 1475 BTRFS_DATA_RELOC_TREE_OBJECTID) { 1476 ret = btrfs_reloc_clone_csums(inode, cur_offset, 1477 num_bytes); 1478 if (ret) { 1479 if (!nolock && nocow) 1480 btrfs_end_write_no_snapshoting(root); 1481 goto error; 1482 } 1483 } 1484 1485 extent_clear_unlock_delalloc(inode, cur_offset, 1486 cur_offset + num_bytes - 1, 1487 locked_page, EXTENT_LOCKED | 1488 EXTENT_DELALLOC, PAGE_UNLOCK | 1489 PAGE_SET_PRIVATE2); 1490 if (!nolock && nocow) 1491 btrfs_end_write_no_snapshoting(root); 1492 cur_offset = extent_end; 1493 if (cur_offset > end) 1494 break; 1495 } 1496 btrfs_release_path(path); 1497 1498 if (cur_offset <= end && cow_start == (u64)-1) { 1499 cow_start = cur_offset; 1500 cur_offset = end; 1501 } 1502 1503 if (cow_start != (u64)-1) { 1504 ret = cow_file_range(inode, locked_page, cow_start, end, 1505 page_started, nr_written, 1); 1506 if (ret) 1507 goto error; 1508 } 1509 1510 error: 1511 err = btrfs_end_transaction(trans, root); 1512 if (!ret) 1513 ret = err; 1514 1515 if (ret && cur_offset < end) 1516 extent_clear_unlock_delalloc(inode, cur_offset, end, 1517 locked_page, EXTENT_LOCKED | 1518 EXTENT_DELALLOC | EXTENT_DEFRAG | 1519 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | 1520 PAGE_CLEAR_DIRTY | 1521 PAGE_SET_WRITEBACK | 1522 PAGE_END_WRITEBACK); 1523 btrfs_free_path(path); 1524 return ret; 1525 } 1526 1527 static inline int need_force_cow(struct inode *inode, u64 start, u64 end) 1528 { 1529 1530 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && 1531 !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)) 1532 return 0; 1533 1534 /* 1535 * @defrag_bytes is a hint value, no spinlock held here, 1536 * if is not zero, it means the file is defragging. 1537 * Force cow if given extent needs to be defragged. 1538 */ 1539 if (BTRFS_I(inode)->defrag_bytes && 1540 test_range_bit(&BTRFS_I(inode)->io_tree, start, end, 1541 EXTENT_DEFRAG, 0, NULL)) 1542 return 1; 1543 1544 return 0; 1545 } 1546 1547 /* 1548 * extent_io.c call back to do delayed allocation processing 1549 */ 1550 static int run_delalloc_range(struct inode *inode, struct page *locked_page, 1551 u64 start, u64 end, int *page_started, 1552 unsigned long *nr_written) 1553 { 1554 int ret; 1555 int force_cow = need_force_cow(inode, start, end); 1556 1557 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW && !force_cow) { 1558 ret = run_delalloc_nocow(inode, locked_page, start, end, 1559 page_started, 1, nr_written); 1560 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC && !force_cow) { 1561 ret = run_delalloc_nocow(inode, locked_page, start, end, 1562 page_started, 0, nr_written); 1563 } else if (!inode_need_compress(inode)) { 1564 ret = cow_file_range(inode, locked_page, start, end, 1565 page_started, nr_written, 1); 1566 } else { 1567 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 1568 &BTRFS_I(inode)->runtime_flags); 1569 ret = cow_file_range_async(inode, locked_page, start, end, 1570 page_started, nr_written); 1571 } 1572 return ret; 1573 } 1574 1575 static void btrfs_split_extent_hook(struct inode *inode, 1576 struct extent_state *orig, u64 split) 1577 { 1578 u64 size; 1579 1580 /* not delalloc, ignore it */ 1581 if (!(orig->state & EXTENT_DELALLOC)) 1582 return; 1583 1584 size = orig->end - orig->start + 1; 1585 if (size > BTRFS_MAX_EXTENT_SIZE) { 1586 u64 num_extents; 1587 u64 new_size; 1588 1589 /* 1590 * See the explanation in btrfs_merge_extent_hook, the same 1591 * applies here, just in reverse. 1592 */ 1593 new_size = orig->end - split + 1; 1594 num_extents = div64_u64(new_size + BTRFS_MAX_EXTENT_SIZE - 1, 1595 BTRFS_MAX_EXTENT_SIZE); 1596 new_size = split - orig->start; 1597 num_extents += div64_u64(new_size + BTRFS_MAX_EXTENT_SIZE - 1, 1598 BTRFS_MAX_EXTENT_SIZE); 1599 if (div64_u64(size + BTRFS_MAX_EXTENT_SIZE - 1, 1600 BTRFS_MAX_EXTENT_SIZE) >= num_extents) 1601 return; 1602 } 1603 1604 spin_lock(&BTRFS_I(inode)->lock); 1605 BTRFS_I(inode)->outstanding_extents++; 1606 spin_unlock(&BTRFS_I(inode)->lock); 1607 } 1608 1609 /* 1610 * extent_io.c merge_extent_hook, used to track merged delayed allocation 1611 * extents so we can keep track of new extents that are just merged onto old 1612 * extents, such as when we are doing sequential writes, so we can properly 1613 * account for the metadata space we'll need. 1614 */ 1615 static void btrfs_merge_extent_hook(struct inode *inode, 1616 struct extent_state *new, 1617 struct extent_state *other) 1618 { 1619 u64 new_size, old_size; 1620 u64 num_extents; 1621 1622 /* not delalloc, ignore it */ 1623 if (!(other->state & EXTENT_DELALLOC)) 1624 return; 1625 1626 if (new->start > other->start) 1627 new_size = new->end - other->start + 1; 1628 else 1629 new_size = other->end - new->start + 1; 1630 1631 /* we're not bigger than the max, unreserve the space and go */ 1632 if (new_size <= BTRFS_MAX_EXTENT_SIZE) { 1633 spin_lock(&BTRFS_I(inode)->lock); 1634 BTRFS_I(inode)->outstanding_extents--; 1635 spin_unlock(&BTRFS_I(inode)->lock); 1636 return; 1637 } 1638 1639 /* 1640 * We have to add up either side to figure out how many extents were 1641 * accounted for before we merged into one big extent. If the number of 1642 * extents we accounted for is <= the amount we need for the new range 1643 * then we can return, otherwise drop. Think of it like this 1644 * 1645 * [ 4k][MAX_SIZE] 1646 * 1647 * So we've grown the extent by a MAX_SIZE extent, this would mean we 1648 * need 2 outstanding extents, on one side we have 1 and the other side 1649 * we have 1 so they are == and we can return. But in this case 1650 * 1651 * [MAX_SIZE+4k][MAX_SIZE+4k] 1652 * 1653 * Each range on their own accounts for 2 extents, but merged together 1654 * they are only 3 extents worth of accounting, so we need to drop in 1655 * this case. 1656 */ 1657 old_size = other->end - other->start + 1; 1658 num_extents = div64_u64(old_size + BTRFS_MAX_EXTENT_SIZE - 1, 1659 BTRFS_MAX_EXTENT_SIZE); 1660 old_size = new->end - new->start + 1; 1661 num_extents += div64_u64(old_size + BTRFS_MAX_EXTENT_SIZE - 1, 1662 BTRFS_MAX_EXTENT_SIZE); 1663 1664 if (div64_u64(new_size + BTRFS_MAX_EXTENT_SIZE - 1, 1665 BTRFS_MAX_EXTENT_SIZE) >= num_extents) 1666 return; 1667 1668 spin_lock(&BTRFS_I(inode)->lock); 1669 BTRFS_I(inode)->outstanding_extents--; 1670 spin_unlock(&BTRFS_I(inode)->lock); 1671 } 1672 1673 static void btrfs_add_delalloc_inodes(struct btrfs_root *root, 1674 struct inode *inode) 1675 { 1676 spin_lock(&root->delalloc_lock); 1677 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) { 1678 list_add_tail(&BTRFS_I(inode)->delalloc_inodes, 1679 &root->delalloc_inodes); 1680 set_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1681 &BTRFS_I(inode)->runtime_flags); 1682 root->nr_delalloc_inodes++; 1683 if (root->nr_delalloc_inodes == 1) { 1684 spin_lock(&root->fs_info->delalloc_root_lock); 1685 BUG_ON(!list_empty(&root->delalloc_root)); 1686 list_add_tail(&root->delalloc_root, 1687 &root->fs_info->delalloc_roots); 1688 spin_unlock(&root->fs_info->delalloc_root_lock); 1689 } 1690 } 1691 spin_unlock(&root->delalloc_lock); 1692 } 1693 1694 static void btrfs_del_delalloc_inode(struct btrfs_root *root, 1695 struct inode *inode) 1696 { 1697 spin_lock(&root->delalloc_lock); 1698 if (!list_empty(&BTRFS_I(inode)->delalloc_inodes)) { 1699 list_del_init(&BTRFS_I(inode)->delalloc_inodes); 1700 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1701 &BTRFS_I(inode)->runtime_flags); 1702 root->nr_delalloc_inodes--; 1703 if (!root->nr_delalloc_inodes) { 1704 spin_lock(&root->fs_info->delalloc_root_lock); 1705 BUG_ON(list_empty(&root->delalloc_root)); 1706 list_del_init(&root->delalloc_root); 1707 spin_unlock(&root->fs_info->delalloc_root_lock); 1708 } 1709 } 1710 spin_unlock(&root->delalloc_lock); 1711 } 1712 1713 /* 1714 * extent_io.c set_bit_hook, used to track delayed allocation 1715 * bytes in this file, and to maintain the list of inodes that 1716 * have pending delalloc work to be done. 1717 */ 1718 static void btrfs_set_bit_hook(struct inode *inode, 1719 struct extent_state *state, unsigned *bits) 1720 { 1721 1722 if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC)) 1723 WARN_ON(1); 1724 /* 1725 * set_bit and clear bit hooks normally require _irqsave/restore 1726 * but in this case, we are only testing for the DELALLOC 1727 * bit, which is only set or cleared with irqs on 1728 */ 1729 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { 1730 struct btrfs_root *root = BTRFS_I(inode)->root; 1731 u64 len = state->end + 1 - state->start; 1732 bool do_list = !btrfs_is_free_space_inode(inode); 1733 1734 if (*bits & EXTENT_FIRST_DELALLOC) { 1735 *bits &= ~EXTENT_FIRST_DELALLOC; 1736 } else { 1737 spin_lock(&BTRFS_I(inode)->lock); 1738 BTRFS_I(inode)->outstanding_extents++; 1739 spin_unlock(&BTRFS_I(inode)->lock); 1740 } 1741 1742 /* For sanity tests */ 1743 if (btrfs_test_is_dummy_root(root)) 1744 return; 1745 1746 __percpu_counter_add(&root->fs_info->delalloc_bytes, len, 1747 root->fs_info->delalloc_batch); 1748 spin_lock(&BTRFS_I(inode)->lock); 1749 BTRFS_I(inode)->delalloc_bytes += len; 1750 if (*bits & EXTENT_DEFRAG) 1751 BTRFS_I(inode)->defrag_bytes += len; 1752 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1753 &BTRFS_I(inode)->runtime_flags)) 1754 btrfs_add_delalloc_inodes(root, inode); 1755 spin_unlock(&BTRFS_I(inode)->lock); 1756 } 1757 } 1758 1759 /* 1760 * extent_io.c clear_bit_hook, see set_bit_hook for why 1761 */ 1762 static void btrfs_clear_bit_hook(struct inode *inode, 1763 struct extent_state *state, 1764 unsigned *bits) 1765 { 1766 u64 len = state->end + 1 - state->start; 1767 u64 num_extents = div64_u64(len + BTRFS_MAX_EXTENT_SIZE -1, 1768 BTRFS_MAX_EXTENT_SIZE); 1769 1770 spin_lock(&BTRFS_I(inode)->lock); 1771 if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) 1772 BTRFS_I(inode)->defrag_bytes -= len; 1773 spin_unlock(&BTRFS_I(inode)->lock); 1774 1775 /* 1776 * set_bit and clear bit hooks normally require _irqsave/restore 1777 * but in this case, we are only testing for the DELALLOC 1778 * bit, which is only set or cleared with irqs on 1779 */ 1780 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { 1781 struct btrfs_root *root = BTRFS_I(inode)->root; 1782 bool do_list = !btrfs_is_free_space_inode(inode); 1783 1784 if (*bits & EXTENT_FIRST_DELALLOC) { 1785 *bits &= ~EXTENT_FIRST_DELALLOC; 1786 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) { 1787 spin_lock(&BTRFS_I(inode)->lock); 1788 BTRFS_I(inode)->outstanding_extents -= num_extents; 1789 spin_unlock(&BTRFS_I(inode)->lock); 1790 } 1791 1792 /* 1793 * We don't reserve metadata space for space cache inodes so we 1794 * don't need to call dellalloc_release_metadata if there is an 1795 * error. 1796 */ 1797 if (*bits & EXTENT_DO_ACCOUNTING && 1798 root != root->fs_info->tree_root) 1799 btrfs_delalloc_release_metadata(inode, len); 1800 1801 /* For sanity tests. */ 1802 if (btrfs_test_is_dummy_root(root)) 1803 return; 1804 1805 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID 1806 && do_list && !(state->state & EXTENT_NORESERVE)) 1807 btrfs_free_reserved_data_space_noquota(inode, 1808 state->start, len); 1809 1810 __percpu_counter_add(&root->fs_info->delalloc_bytes, -len, 1811 root->fs_info->delalloc_batch); 1812 spin_lock(&BTRFS_I(inode)->lock); 1813 BTRFS_I(inode)->delalloc_bytes -= len; 1814 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 && 1815 test_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1816 &BTRFS_I(inode)->runtime_flags)) 1817 btrfs_del_delalloc_inode(root, inode); 1818 spin_unlock(&BTRFS_I(inode)->lock); 1819 } 1820 } 1821 1822 /* 1823 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure 1824 * we don't create bios that span stripes or chunks 1825 */ 1826 int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset, 1827 size_t size, struct bio *bio, 1828 unsigned long bio_flags) 1829 { 1830 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; 1831 u64 logical = (u64)bio->bi_iter.bi_sector << 9; 1832 u64 length = 0; 1833 u64 map_length; 1834 int ret; 1835 1836 if (bio_flags & EXTENT_BIO_COMPRESSED) 1837 return 0; 1838 1839 length = bio->bi_iter.bi_size; 1840 map_length = length; 1841 ret = btrfs_map_block(root->fs_info, rw, logical, 1842 &map_length, NULL, 0); 1843 /* Will always return 0 with map_multi == NULL */ 1844 BUG_ON(ret < 0); 1845 if (map_length < length + size) 1846 return 1; 1847 return 0; 1848 } 1849 1850 /* 1851 * in order to insert checksums into the metadata in large chunks, 1852 * we wait until bio submission time. All the pages in the bio are 1853 * checksummed and sums are attached onto the ordered extent record. 1854 * 1855 * At IO completion time the cums attached on the ordered extent record 1856 * are inserted into the btree 1857 */ 1858 static int __btrfs_submit_bio_start(struct inode *inode, int rw, 1859 struct bio *bio, int mirror_num, 1860 unsigned long bio_flags, 1861 u64 bio_offset) 1862 { 1863 struct btrfs_root *root = BTRFS_I(inode)->root; 1864 int ret = 0; 1865 1866 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0); 1867 BUG_ON(ret); /* -ENOMEM */ 1868 return 0; 1869 } 1870 1871 /* 1872 * in order to insert checksums into the metadata in large chunks, 1873 * we wait until bio submission time. All the pages in the bio are 1874 * checksummed and sums are attached onto the ordered extent record. 1875 * 1876 * At IO completion time the cums attached on the ordered extent record 1877 * are inserted into the btree 1878 */ 1879 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio, 1880 int mirror_num, unsigned long bio_flags, 1881 u64 bio_offset) 1882 { 1883 struct btrfs_root *root = BTRFS_I(inode)->root; 1884 int ret; 1885 1886 ret = btrfs_map_bio(root, rw, bio, mirror_num, 1); 1887 if (ret) { 1888 bio->bi_error = ret; 1889 bio_endio(bio); 1890 } 1891 return ret; 1892 } 1893 1894 /* 1895 * extent_io.c submission hook. This does the right thing for csum calculation 1896 * on write, or reading the csums from the tree before a read 1897 */ 1898 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, 1899 int mirror_num, unsigned long bio_flags, 1900 u64 bio_offset) 1901 { 1902 struct btrfs_root *root = BTRFS_I(inode)->root; 1903 enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA; 1904 int ret = 0; 1905 int skip_sum; 1906 int async = !atomic_read(&BTRFS_I(inode)->sync_writers); 1907 1908 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 1909 1910 if (btrfs_is_free_space_inode(inode)) 1911 metadata = BTRFS_WQ_ENDIO_FREE_SPACE; 1912 1913 if (!(rw & REQ_WRITE)) { 1914 ret = btrfs_bio_wq_end_io(root->fs_info, bio, metadata); 1915 if (ret) 1916 goto out; 1917 1918 if (bio_flags & EXTENT_BIO_COMPRESSED) { 1919 ret = btrfs_submit_compressed_read(inode, bio, 1920 mirror_num, 1921 bio_flags); 1922 goto out; 1923 } else if (!skip_sum) { 1924 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL); 1925 if (ret) 1926 goto out; 1927 } 1928 goto mapit; 1929 } else if (async && !skip_sum) { 1930 /* csum items have already been cloned */ 1931 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) 1932 goto mapit; 1933 /* we're doing a write, do the async checksumming */ 1934 ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info, 1935 inode, rw, bio, mirror_num, 1936 bio_flags, bio_offset, 1937 __btrfs_submit_bio_start, 1938 __btrfs_submit_bio_done); 1939 goto out; 1940 } else if (!skip_sum) { 1941 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0); 1942 if (ret) 1943 goto out; 1944 } 1945 1946 mapit: 1947 ret = btrfs_map_bio(root, rw, bio, mirror_num, 0); 1948 1949 out: 1950 if (ret < 0) { 1951 bio->bi_error = ret; 1952 bio_endio(bio); 1953 } 1954 return ret; 1955 } 1956 1957 /* 1958 * given a list of ordered sums record them in the inode. This happens 1959 * at IO completion time based on sums calculated at bio submission time. 1960 */ 1961 static noinline int add_pending_csums(struct btrfs_trans_handle *trans, 1962 struct inode *inode, u64 file_offset, 1963 struct list_head *list) 1964 { 1965 struct btrfs_ordered_sum *sum; 1966 1967 list_for_each_entry(sum, list, list) { 1968 trans->adding_csums = 1; 1969 btrfs_csum_file_blocks(trans, 1970 BTRFS_I(inode)->root->fs_info->csum_root, sum); 1971 trans->adding_csums = 0; 1972 } 1973 return 0; 1974 } 1975 1976 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, 1977 struct extent_state **cached_state) 1978 { 1979 WARN_ON((end & (PAGE_SIZE - 1)) == 0); 1980 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end, 1981 cached_state); 1982 } 1983 1984 /* see btrfs_writepage_start_hook for details on why this is required */ 1985 struct btrfs_writepage_fixup { 1986 struct page *page; 1987 struct btrfs_work work; 1988 }; 1989 1990 static void btrfs_writepage_fixup_worker(struct btrfs_work *work) 1991 { 1992 struct btrfs_writepage_fixup *fixup; 1993 struct btrfs_ordered_extent *ordered; 1994 struct extent_state *cached_state = NULL; 1995 struct page *page; 1996 struct inode *inode; 1997 u64 page_start; 1998 u64 page_end; 1999 int ret; 2000 2001 fixup = container_of(work, struct btrfs_writepage_fixup, work); 2002 page = fixup->page; 2003 again: 2004 lock_page(page); 2005 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { 2006 ClearPageChecked(page); 2007 goto out_page; 2008 } 2009 2010 inode = page->mapping->host; 2011 page_start = page_offset(page); 2012 page_end = page_offset(page) + PAGE_SIZE - 1; 2013 2014 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 2015 &cached_state); 2016 2017 /* already ordered? We're done */ 2018 if (PagePrivate2(page)) 2019 goto out; 2020 2021 ordered = btrfs_lookup_ordered_range(inode, page_start, 2022 PAGE_SIZE); 2023 if (ordered) { 2024 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, 2025 page_end, &cached_state, GFP_NOFS); 2026 unlock_page(page); 2027 btrfs_start_ordered_extent(inode, ordered, 1); 2028 btrfs_put_ordered_extent(ordered); 2029 goto again; 2030 } 2031 2032 ret = btrfs_delalloc_reserve_space(inode, page_start, 2033 PAGE_SIZE); 2034 if (ret) { 2035 mapping_set_error(page->mapping, ret); 2036 end_extent_writepage(page, ret, page_start, page_end); 2037 ClearPageChecked(page); 2038 goto out; 2039 } 2040 2041 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state); 2042 ClearPageChecked(page); 2043 set_page_dirty(page); 2044 out: 2045 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, 2046 &cached_state, GFP_NOFS); 2047 out_page: 2048 unlock_page(page); 2049 put_page(page); 2050 kfree(fixup); 2051 } 2052 2053 /* 2054 * There are a few paths in the higher layers of the kernel that directly 2055 * set the page dirty bit without asking the filesystem if it is a 2056 * good idea. This causes problems because we want to make sure COW 2057 * properly happens and the data=ordered rules are followed. 2058 * 2059 * In our case any range that doesn't have the ORDERED bit set 2060 * hasn't been properly setup for IO. We kick off an async process 2061 * to fix it up. The async helper will wait for ordered extents, set 2062 * the delalloc bit and make it safe to write the page. 2063 */ 2064 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) 2065 { 2066 struct inode *inode = page->mapping->host; 2067 struct btrfs_writepage_fixup *fixup; 2068 struct btrfs_root *root = BTRFS_I(inode)->root; 2069 2070 /* this page is properly in the ordered list */ 2071 if (TestClearPagePrivate2(page)) 2072 return 0; 2073 2074 if (PageChecked(page)) 2075 return -EAGAIN; 2076 2077 fixup = kzalloc(sizeof(*fixup), GFP_NOFS); 2078 if (!fixup) 2079 return -EAGAIN; 2080 2081 SetPageChecked(page); 2082 get_page(page); 2083 btrfs_init_work(&fixup->work, btrfs_fixup_helper, 2084 btrfs_writepage_fixup_worker, NULL, NULL); 2085 fixup->page = page; 2086 btrfs_queue_work(root->fs_info->fixup_workers, &fixup->work); 2087 return -EBUSY; 2088 } 2089 2090 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, 2091 struct inode *inode, u64 file_pos, 2092 u64 disk_bytenr, u64 disk_num_bytes, 2093 u64 num_bytes, u64 ram_bytes, 2094 u8 compression, u8 encryption, 2095 u16 other_encoding, int extent_type) 2096 { 2097 struct btrfs_root *root = BTRFS_I(inode)->root; 2098 struct btrfs_file_extent_item *fi; 2099 struct btrfs_path *path; 2100 struct extent_buffer *leaf; 2101 struct btrfs_key ins; 2102 int extent_inserted = 0; 2103 int ret; 2104 2105 path = btrfs_alloc_path(); 2106 if (!path) 2107 return -ENOMEM; 2108 2109 /* 2110 * we may be replacing one extent in the tree with another. 2111 * The new extent is pinned in the extent map, and we don't want 2112 * to drop it from the cache until it is completely in the btree. 2113 * 2114 * So, tell btrfs_drop_extents to leave this extent in the cache. 2115 * the caller is expected to unpin it and allow it to be merged 2116 * with the others. 2117 */ 2118 ret = __btrfs_drop_extents(trans, root, inode, path, file_pos, 2119 file_pos + num_bytes, NULL, 0, 2120 1, sizeof(*fi), &extent_inserted); 2121 if (ret) 2122 goto out; 2123 2124 if (!extent_inserted) { 2125 ins.objectid = btrfs_ino(inode); 2126 ins.offset = file_pos; 2127 ins.type = BTRFS_EXTENT_DATA_KEY; 2128 2129 path->leave_spinning = 1; 2130 ret = btrfs_insert_empty_item(trans, root, path, &ins, 2131 sizeof(*fi)); 2132 if (ret) 2133 goto out; 2134 } 2135 leaf = path->nodes[0]; 2136 fi = btrfs_item_ptr(leaf, path->slots[0], 2137 struct btrfs_file_extent_item); 2138 btrfs_set_file_extent_generation(leaf, fi, trans->transid); 2139 btrfs_set_file_extent_type(leaf, fi, extent_type); 2140 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); 2141 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes); 2142 btrfs_set_file_extent_offset(leaf, fi, 0); 2143 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); 2144 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes); 2145 btrfs_set_file_extent_compression(leaf, fi, compression); 2146 btrfs_set_file_extent_encryption(leaf, fi, encryption); 2147 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding); 2148 2149 btrfs_mark_buffer_dirty(leaf); 2150 btrfs_release_path(path); 2151 2152 inode_add_bytes(inode, num_bytes); 2153 2154 ins.objectid = disk_bytenr; 2155 ins.offset = disk_num_bytes; 2156 ins.type = BTRFS_EXTENT_ITEM_KEY; 2157 ret = btrfs_alloc_reserved_file_extent(trans, root, 2158 root->root_key.objectid, 2159 btrfs_ino(inode), file_pos, 2160 ram_bytes, &ins); 2161 /* 2162 * Release the reserved range from inode dirty range map, as it is 2163 * already moved into delayed_ref_head 2164 */ 2165 btrfs_qgroup_release_data(inode, file_pos, ram_bytes); 2166 out: 2167 btrfs_free_path(path); 2168 2169 return ret; 2170 } 2171 2172 /* snapshot-aware defrag */ 2173 struct sa_defrag_extent_backref { 2174 struct rb_node node; 2175 struct old_sa_defrag_extent *old; 2176 u64 root_id; 2177 u64 inum; 2178 u64 file_pos; 2179 u64 extent_offset; 2180 u64 num_bytes; 2181 u64 generation; 2182 }; 2183 2184 struct old_sa_defrag_extent { 2185 struct list_head list; 2186 struct new_sa_defrag_extent *new; 2187 2188 u64 extent_offset; 2189 u64 bytenr; 2190 u64 offset; 2191 u64 len; 2192 int count; 2193 }; 2194 2195 struct new_sa_defrag_extent { 2196 struct rb_root root; 2197 struct list_head head; 2198 struct btrfs_path *path; 2199 struct inode *inode; 2200 u64 file_pos; 2201 u64 len; 2202 u64 bytenr; 2203 u64 disk_len; 2204 u8 compress_type; 2205 }; 2206 2207 static int backref_comp(struct sa_defrag_extent_backref *b1, 2208 struct sa_defrag_extent_backref *b2) 2209 { 2210 if (b1->root_id < b2->root_id) 2211 return -1; 2212 else if (b1->root_id > b2->root_id) 2213 return 1; 2214 2215 if (b1->inum < b2->inum) 2216 return -1; 2217 else if (b1->inum > b2->inum) 2218 return 1; 2219 2220 if (b1->file_pos < b2->file_pos) 2221 return -1; 2222 else if (b1->file_pos > b2->file_pos) 2223 return 1; 2224 2225 /* 2226 * [------------------------------] ===> (a range of space) 2227 * |<--->| |<---->| =============> (fs/file tree A) 2228 * |<---------------------------->| ===> (fs/file tree B) 2229 * 2230 * A range of space can refer to two file extents in one tree while 2231 * refer to only one file extent in another tree. 2232 * 2233 * So we may process a disk offset more than one time(two extents in A) 2234 * and locate at the same extent(one extent in B), then insert two same 2235 * backrefs(both refer to the extent in B). 2236 */ 2237 return 0; 2238 } 2239 2240 static void backref_insert(struct rb_root *root, 2241 struct sa_defrag_extent_backref *backref) 2242 { 2243 struct rb_node **p = &root->rb_node; 2244 struct rb_node *parent = NULL; 2245 struct sa_defrag_extent_backref *entry; 2246 int ret; 2247 2248 while (*p) { 2249 parent = *p; 2250 entry = rb_entry(parent, struct sa_defrag_extent_backref, node); 2251 2252 ret = backref_comp(backref, entry); 2253 if (ret < 0) 2254 p = &(*p)->rb_left; 2255 else 2256 p = &(*p)->rb_right; 2257 } 2258 2259 rb_link_node(&backref->node, parent, p); 2260 rb_insert_color(&backref->node, root); 2261 } 2262 2263 /* 2264 * Note the backref might has changed, and in this case we just return 0. 2265 */ 2266 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id, 2267 void *ctx) 2268 { 2269 struct btrfs_file_extent_item *extent; 2270 struct btrfs_fs_info *fs_info; 2271 struct old_sa_defrag_extent *old = ctx; 2272 struct new_sa_defrag_extent *new = old->new; 2273 struct btrfs_path *path = new->path; 2274 struct btrfs_key key; 2275 struct btrfs_root *root; 2276 struct sa_defrag_extent_backref *backref; 2277 struct extent_buffer *leaf; 2278 struct inode *inode = new->inode; 2279 int slot; 2280 int ret; 2281 u64 extent_offset; 2282 u64 num_bytes; 2283 2284 if (BTRFS_I(inode)->root->root_key.objectid == root_id && 2285 inum == btrfs_ino(inode)) 2286 return 0; 2287 2288 key.objectid = root_id; 2289 key.type = BTRFS_ROOT_ITEM_KEY; 2290 key.offset = (u64)-1; 2291 2292 fs_info = BTRFS_I(inode)->root->fs_info; 2293 root = btrfs_read_fs_root_no_name(fs_info, &key); 2294 if (IS_ERR(root)) { 2295 if (PTR_ERR(root) == -ENOENT) 2296 return 0; 2297 WARN_ON(1); 2298 pr_debug("inum=%llu, offset=%llu, root_id=%llu\n", 2299 inum, offset, root_id); 2300 return PTR_ERR(root); 2301 } 2302 2303 key.objectid = inum; 2304 key.type = BTRFS_EXTENT_DATA_KEY; 2305 if (offset > (u64)-1 << 32) 2306 key.offset = 0; 2307 else 2308 key.offset = offset; 2309 2310 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2311 if (WARN_ON(ret < 0)) 2312 return ret; 2313 ret = 0; 2314 2315 while (1) { 2316 cond_resched(); 2317 2318 leaf = path->nodes[0]; 2319 slot = path->slots[0]; 2320 2321 if (slot >= btrfs_header_nritems(leaf)) { 2322 ret = btrfs_next_leaf(root, path); 2323 if (ret < 0) { 2324 goto out; 2325 } else if (ret > 0) { 2326 ret = 0; 2327 goto out; 2328 } 2329 continue; 2330 } 2331 2332 path->slots[0]++; 2333 2334 btrfs_item_key_to_cpu(leaf, &key, slot); 2335 2336 if (key.objectid > inum) 2337 goto out; 2338 2339 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY) 2340 continue; 2341 2342 extent = btrfs_item_ptr(leaf, slot, 2343 struct btrfs_file_extent_item); 2344 2345 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr) 2346 continue; 2347 2348 /* 2349 * 'offset' refers to the exact key.offset, 2350 * NOT the 'offset' field in btrfs_extent_data_ref, ie. 2351 * (key.offset - extent_offset). 2352 */ 2353 if (key.offset != offset) 2354 continue; 2355 2356 extent_offset = btrfs_file_extent_offset(leaf, extent); 2357 num_bytes = btrfs_file_extent_num_bytes(leaf, extent); 2358 2359 if (extent_offset >= old->extent_offset + old->offset + 2360 old->len || extent_offset + num_bytes <= 2361 old->extent_offset + old->offset) 2362 continue; 2363 break; 2364 } 2365 2366 backref = kmalloc(sizeof(*backref), GFP_NOFS); 2367 if (!backref) { 2368 ret = -ENOENT; 2369 goto out; 2370 } 2371 2372 backref->root_id = root_id; 2373 backref->inum = inum; 2374 backref->file_pos = offset; 2375 backref->num_bytes = num_bytes; 2376 backref->extent_offset = extent_offset; 2377 backref->generation = btrfs_file_extent_generation(leaf, extent); 2378 backref->old = old; 2379 backref_insert(&new->root, backref); 2380 old->count++; 2381 out: 2382 btrfs_release_path(path); 2383 WARN_ON(ret); 2384 return ret; 2385 } 2386 2387 static noinline bool record_extent_backrefs(struct btrfs_path *path, 2388 struct new_sa_defrag_extent *new) 2389 { 2390 struct btrfs_fs_info *fs_info = BTRFS_I(new->inode)->root->fs_info; 2391 struct old_sa_defrag_extent *old, *tmp; 2392 int ret; 2393 2394 new->path = path; 2395 2396 list_for_each_entry_safe(old, tmp, &new->head, list) { 2397 ret = iterate_inodes_from_logical(old->bytenr + 2398 old->extent_offset, fs_info, 2399 path, record_one_backref, 2400 old); 2401 if (ret < 0 && ret != -ENOENT) 2402 return false; 2403 2404 /* no backref to be processed for this extent */ 2405 if (!old->count) { 2406 list_del(&old->list); 2407 kfree(old); 2408 } 2409 } 2410 2411 if (list_empty(&new->head)) 2412 return false; 2413 2414 return true; 2415 } 2416 2417 static int relink_is_mergable(struct extent_buffer *leaf, 2418 struct btrfs_file_extent_item *fi, 2419 struct new_sa_defrag_extent *new) 2420 { 2421 if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr) 2422 return 0; 2423 2424 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) 2425 return 0; 2426 2427 if (btrfs_file_extent_compression(leaf, fi) != new->compress_type) 2428 return 0; 2429 2430 if (btrfs_file_extent_encryption(leaf, fi) || 2431 btrfs_file_extent_other_encoding(leaf, fi)) 2432 return 0; 2433 2434 return 1; 2435 } 2436 2437 /* 2438 * Note the backref might has changed, and in this case we just return 0. 2439 */ 2440 static noinline int relink_extent_backref(struct btrfs_path *path, 2441 struct sa_defrag_extent_backref *prev, 2442 struct sa_defrag_extent_backref *backref) 2443 { 2444 struct btrfs_file_extent_item *extent; 2445 struct btrfs_file_extent_item *item; 2446 struct btrfs_ordered_extent *ordered; 2447 struct btrfs_trans_handle *trans; 2448 struct btrfs_fs_info *fs_info; 2449 struct btrfs_root *root; 2450 struct btrfs_key key; 2451 struct extent_buffer *leaf; 2452 struct old_sa_defrag_extent *old = backref->old; 2453 struct new_sa_defrag_extent *new = old->new; 2454 struct inode *src_inode = new->inode; 2455 struct inode *inode; 2456 struct extent_state *cached = NULL; 2457 int ret = 0; 2458 u64 start; 2459 u64 len; 2460 u64 lock_start; 2461 u64 lock_end; 2462 bool merge = false; 2463 int index; 2464 2465 if (prev && prev->root_id == backref->root_id && 2466 prev->inum == backref->inum && 2467 prev->file_pos + prev->num_bytes == backref->file_pos) 2468 merge = true; 2469 2470 /* step 1: get root */ 2471 key.objectid = backref->root_id; 2472 key.type = BTRFS_ROOT_ITEM_KEY; 2473 key.offset = (u64)-1; 2474 2475 fs_info = BTRFS_I(src_inode)->root->fs_info; 2476 index = srcu_read_lock(&fs_info->subvol_srcu); 2477 2478 root = btrfs_read_fs_root_no_name(fs_info, &key); 2479 if (IS_ERR(root)) { 2480 srcu_read_unlock(&fs_info->subvol_srcu, index); 2481 if (PTR_ERR(root) == -ENOENT) 2482 return 0; 2483 return PTR_ERR(root); 2484 } 2485 2486 if (btrfs_root_readonly(root)) { 2487 srcu_read_unlock(&fs_info->subvol_srcu, index); 2488 return 0; 2489 } 2490 2491 /* step 2: get inode */ 2492 key.objectid = backref->inum; 2493 key.type = BTRFS_INODE_ITEM_KEY; 2494 key.offset = 0; 2495 2496 inode = btrfs_iget(fs_info->sb, &key, root, NULL); 2497 if (IS_ERR(inode)) { 2498 srcu_read_unlock(&fs_info->subvol_srcu, index); 2499 return 0; 2500 } 2501 2502 srcu_read_unlock(&fs_info->subvol_srcu, index); 2503 2504 /* step 3: relink backref */ 2505 lock_start = backref->file_pos; 2506 lock_end = backref->file_pos + backref->num_bytes - 1; 2507 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end, 2508 &cached); 2509 2510 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end); 2511 if (ordered) { 2512 btrfs_put_ordered_extent(ordered); 2513 goto out_unlock; 2514 } 2515 2516 trans = btrfs_join_transaction(root); 2517 if (IS_ERR(trans)) { 2518 ret = PTR_ERR(trans); 2519 goto out_unlock; 2520 } 2521 2522 key.objectid = backref->inum; 2523 key.type = BTRFS_EXTENT_DATA_KEY; 2524 key.offset = backref->file_pos; 2525 2526 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2527 if (ret < 0) { 2528 goto out_free_path; 2529 } else if (ret > 0) { 2530 ret = 0; 2531 goto out_free_path; 2532 } 2533 2534 extent = btrfs_item_ptr(path->nodes[0], path->slots[0], 2535 struct btrfs_file_extent_item); 2536 2537 if (btrfs_file_extent_generation(path->nodes[0], extent) != 2538 backref->generation) 2539 goto out_free_path; 2540 2541 btrfs_release_path(path); 2542 2543 start = backref->file_pos; 2544 if (backref->extent_offset < old->extent_offset + old->offset) 2545 start += old->extent_offset + old->offset - 2546 backref->extent_offset; 2547 2548 len = min(backref->extent_offset + backref->num_bytes, 2549 old->extent_offset + old->offset + old->len); 2550 len -= max(backref->extent_offset, old->extent_offset + old->offset); 2551 2552 ret = btrfs_drop_extents(trans, root, inode, start, 2553 start + len, 1); 2554 if (ret) 2555 goto out_free_path; 2556 again: 2557 key.objectid = btrfs_ino(inode); 2558 key.type = BTRFS_EXTENT_DATA_KEY; 2559 key.offset = start; 2560 2561 path->leave_spinning = 1; 2562 if (merge) { 2563 struct btrfs_file_extent_item *fi; 2564 u64 extent_len; 2565 struct btrfs_key found_key; 2566 2567 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2568 if (ret < 0) 2569 goto out_free_path; 2570 2571 path->slots[0]--; 2572 leaf = path->nodes[0]; 2573 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2574 2575 fi = btrfs_item_ptr(leaf, path->slots[0], 2576 struct btrfs_file_extent_item); 2577 extent_len = btrfs_file_extent_num_bytes(leaf, fi); 2578 2579 if (extent_len + found_key.offset == start && 2580 relink_is_mergable(leaf, fi, new)) { 2581 btrfs_set_file_extent_num_bytes(leaf, fi, 2582 extent_len + len); 2583 btrfs_mark_buffer_dirty(leaf); 2584 inode_add_bytes(inode, len); 2585 2586 ret = 1; 2587 goto out_free_path; 2588 } else { 2589 merge = false; 2590 btrfs_release_path(path); 2591 goto again; 2592 } 2593 } 2594 2595 ret = btrfs_insert_empty_item(trans, root, path, &key, 2596 sizeof(*extent)); 2597 if (ret) { 2598 btrfs_abort_transaction(trans, root, ret); 2599 goto out_free_path; 2600 } 2601 2602 leaf = path->nodes[0]; 2603 item = btrfs_item_ptr(leaf, path->slots[0], 2604 struct btrfs_file_extent_item); 2605 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr); 2606 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len); 2607 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos); 2608 btrfs_set_file_extent_num_bytes(leaf, item, len); 2609 btrfs_set_file_extent_ram_bytes(leaf, item, new->len); 2610 btrfs_set_file_extent_generation(leaf, item, trans->transid); 2611 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG); 2612 btrfs_set_file_extent_compression(leaf, item, new->compress_type); 2613 btrfs_set_file_extent_encryption(leaf, item, 0); 2614 btrfs_set_file_extent_other_encoding(leaf, item, 0); 2615 2616 btrfs_mark_buffer_dirty(leaf); 2617 inode_add_bytes(inode, len); 2618 btrfs_release_path(path); 2619 2620 ret = btrfs_inc_extent_ref(trans, root, new->bytenr, 2621 new->disk_len, 0, 2622 backref->root_id, backref->inum, 2623 new->file_pos); /* start - extent_offset */ 2624 if (ret) { 2625 btrfs_abort_transaction(trans, root, ret); 2626 goto out_free_path; 2627 } 2628 2629 ret = 1; 2630 out_free_path: 2631 btrfs_release_path(path); 2632 path->leave_spinning = 0; 2633 btrfs_end_transaction(trans, root); 2634 out_unlock: 2635 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end, 2636 &cached, GFP_NOFS); 2637 iput(inode); 2638 return ret; 2639 } 2640 2641 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new) 2642 { 2643 struct old_sa_defrag_extent *old, *tmp; 2644 2645 if (!new) 2646 return; 2647 2648 list_for_each_entry_safe(old, tmp, &new->head, list) { 2649 kfree(old); 2650 } 2651 kfree(new); 2652 } 2653 2654 static void relink_file_extents(struct new_sa_defrag_extent *new) 2655 { 2656 struct btrfs_path *path; 2657 struct sa_defrag_extent_backref *backref; 2658 struct sa_defrag_extent_backref *prev = NULL; 2659 struct inode *inode; 2660 struct btrfs_root *root; 2661 struct rb_node *node; 2662 int ret; 2663 2664 inode = new->inode; 2665 root = BTRFS_I(inode)->root; 2666 2667 path = btrfs_alloc_path(); 2668 if (!path) 2669 return; 2670 2671 if (!record_extent_backrefs(path, new)) { 2672 btrfs_free_path(path); 2673 goto out; 2674 } 2675 btrfs_release_path(path); 2676 2677 while (1) { 2678 node = rb_first(&new->root); 2679 if (!node) 2680 break; 2681 rb_erase(node, &new->root); 2682 2683 backref = rb_entry(node, struct sa_defrag_extent_backref, node); 2684 2685 ret = relink_extent_backref(path, prev, backref); 2686 WARN_ON(ret < 0); 2687 2688 kfree(prev); 2689 2690 if (ret == 1) 2691 prev = backref; 2692 else 2693 prev = NULL; 2694 cond_resched(); 2695 } 2696 kfree(prev); 2697 2698 btrfs_free_path(path); 2699 out: 2700 free_sa_defrag_extent(new); 2701 2702 atomic_dec(&root->fs_info->defrag_running); 2703 wake_up(&root->fs_info->transaction_wait); 2704 } 2705 2706 static struct new_sa_defrag_extent * 2707 record_old_file_extents(struct inode *inode, 2708 struct btrfs_ordered_extent *ordered) 2709 { 2710 struct btrfs_root *root = BTRFS_I(inode)->root; 2711 struct btrfs_path *path; 2712 struct btrfs_key key; 2713 struct old_sa_defrag_extent *old; 2714 struct new_sa_defrag_extent *new; 2715 int ret; 2716 2717 new = kmalloc(sizeof(*new), GFP_NOFS); 2718 if (!new) 2719 return NULL; 2720 2721 new->inode = inode; 2722 new->file_pos = ordered->file_offset; 2723 new->len = ordered->len; 2724 new->bytenr = ordered->start; 2725 new->disk_len = ordered->disk_len; 2726 new->compress_type = ordered->compress_type; 2727 new->root = RB_ROOT; 2728 INIT_LIST_HEAD(&new->head); 2729 2730 path = btrfs_alloc_path(); 2731 if (!path) 2732 goto out_kfree; 2733 2734 key.objectid = btrfs_ino(inode); 2735 key.type = BTRFS_EXTENT_DATA_KEY; 2736 key.offset = new->file_pos; 2737 2738 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2739 if (ret < 0) 2740 goto out_free_path; 2741 if (ret > 0 && path->slots[0] > 0) 2742 path->slots[0]--; 2743 2744 /* find out all the old extents for the file range */ 2745 while (1) { 2746 struct btrfs_file_extent_item *extent; 2747 struct extent_buffer *l; 2748 int slot; 2749 u64 num_bytes; 2750 u64 offset; 2751 u64 end; 2752 u64 disk_bytenr; 2753 u64 extent_offset; 2754 2755 l = path->nodes[0]; 2756 slot = path->slots[0]; 2757 2758 if (slot >= btrfs_header_nritems(l)) { 2759 ret = btrfs_next_leaf(root, path); 2760 if (ret < 0) 2761 goto out_free_path; 2762 else if (ret > 0) 2763 break; 2764 continue; 2765 } 2766 2767 btrfs_item_key_to_cpu(l, &key, slot); 2768 2769 if (key.objectid != btrfs_ino(inode)) 2770 break; 2771 if (key.type != BTRFS_EXTENT_DATA_KEY) 2772 break; 2773 if (key.offset >= new->file_pos + new->len) 2774 break; 2775 2776 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item); 2777 2778 num_bytes = btrfs_file_extent_num_bytes(l, extent); 2779 if (key.offset + num_bytes < new->file_pos) 2780 goto next; 2781 2782 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent); 2783 if (!disk_bytenr) 2784 goto next; 2785 2786 extent_offset = btrfs_file_extent_offset(l, extent); 2787 2788 old = kmalloc(sizeof(*old), GFP_NOFS); 2789 if (!old) 2790 goto out_free_path; 2791 2792 offset = max(new->file_pos, key.offset); 2793 end = min(new->file_pos + new->len, key.offset + num_bytes); 2794 2795 old->bytenr = disk_bytenr; 2796 old->extent_offset = extent_offset; 2797 old->offset = offset - key.offset; 2798 old->len = end - offset; 2799 old->new = new; 2800 old->count = 0; 2801 list_add_tail(&old->list, &new->head); 2802 next: 2803 path->slots[0]++; 2804 cond_resched(); 2805 } 2806 2807 btrfs_free_path(path); 2808 atomic_inc(&root->fs_info->defrag_running); 2809 2810 return new; 2811 2812 out_free_path: 2813 btrfs_free_path(path); 2814 out_kfree: 2815 free_sa_defrag_extent(new); 2816 return NULL; 2817 } 2818 2819 static void btrfs_release_delalloc_bytes(struct btrfs_root *root, 2820 u64 start, u64 len) 2821 { 2822 struct btrfs_block_group_cache *cache; 2823 2824 cache = btrfs_lookup_block_group(root->fs_info, start); 2825 ASSERT(cache); 2826 2827 spin_lock(&cache->lock); 2828 cache->delalloc_bytes -= len; 2829 spin_unlock(&cache->lock); 2830 2831 btrfs_put_block_group(cache); 2832 } 2833 2834 /* as ordered data IO finishes, this gets called so we can finish 2835 * an ordered extent if the range of bytes in the file it covers are 2836 * fully written. 2837 */ 2838 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent) 2839 { 2840 struct inode *inode = ordered_extent->inode; 2841 struct btrfs_root *root = BTRFS_I(inode)->root; 2842 struct btrfs_trans_handle *trans = NULL; 2843 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 2844 struct extent_state *cached_state = NULL; 2845 struct new_sa_defrag_extent *new = NULL; 2846 int compress_type = 0; 2847 int ret = 0; 2848 u64 logical_len = ordered_extent->len; 2849 bool nolock; 2850 bool truncated = false; 2851 2852 nolock = btrfs_is_free_space_inode(inode); 2853 2854 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) { 2855 ret = -EIO; 2856 goto out; 2857 } 2858 2859 btrfs_free_io_failure_record(inode, ordered_extent->file_offset, 2860 ordered_extent->file_offset + 2861 ordered_extent->len - 1); 2862 2863 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) { 2864 truncated = true; 2865 logical_len = ordered_extent->truncated_len; 2866 /* Truncated the entire extent, don't bother adding */ 2867 if (!logical_len) 2868 goto out; 2869 } 2870 2871 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { 2872 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */ 2873 2874 /* 2875 * For mwrite(mmap + memset to write) case, we still reserve 2876 * space for NOCOW range. 2877 * As NOCOW won't cause a new delayed ref, just free the space 2878 */ 2879 btrfs_qgroup_free_data(inode, ordered_extent->file_offset, 2880 ordered_extent->len); 2881 btrfs_ordered_update_i_size(inode, 0, ordered_extent); 2882 if (nolock) 2883 trans = btrfs_join_transaction_nolock(root); 2884 else 2885 trans = btrfs_join_transaction(root); 2886 if (IS_ERR(trans)) { 2887 ret = PTR_ERR(trans); 2888 trans = NULL; 2889 goto out; 2890 } 2891 trans->block_rsv = &root->fs_info->delalloc_block_rsv; 2892 ret = btrfs_update_inode_fallback(trans, root, inode); 2893 if (ret) /* -ENOMEM or corruption */ 2894 btrfs_abort_transaction(trans, root, ret); 2895 goto out; 2896 } 2897 2898 lock_extent_bits(io_tree, ordered_extent->file_offset, 2899 ordered_extent->file_offset + ordered_extent->len - 1, 2900 &cached_state); 2901 2902 ret = test_range_bit(io_tree, ordered_extent->file_offset, 2903 ordered_extent->file_offset + ordered_extent->len - 1, 2904 EXTENT_DEFRAG, 1, cached_state); 2905 if (ret) { 2906 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item); 2907 if (0 && last_snapshot >= BTRFS_I(inode)->generation) 2908 /* the inode is shared */ 2909 new = record_old_file_extents(inode, ordered_extent); 2910 2911 clear_extent_bit(io_tree, ordered_extent->file_offset, 2912 ordered_extent->file_offset + ordered_extent->len - 1, 2913 EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS); 2914 } 2915 2916 if (nolock) 2917 trans = btrfs_join_transaction_nolock(root); 2918 else 2919 trans = btrfs_join_transaction(root); 2920 if (IS_ERR(trans)) { 2921 ret = PTR_ERR(trans); 2922 trans = NULL; 2923 goto out_unlock; 2924 } 2925 2926 trans->block_rsv = &root->fs_info->delalloc_block_rsv; 2927 2928 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) 2929 compress_type = ordered_extent->compress_type; 2930 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { 2931 BUG_ON(compress_type); 2932 ret = btrfs_mark_extent_written(trans, inode, 2933 ordered_extent->file_offset, 2934 ordered_extent->file_offset + 2935 logical_len); 2936 } else { 2937 BUG_ON(root == root->fs_info->tree_root); 2938 ret = insert_reserved_file_extent(trans, inode, 2939 ordered_extent->file_offset, 2940 ordered_extent->start, 2941 ordered_extent->disk_len, 2942 logical_len, logical_len, 2943 compress_type, 0, 0, 2944 BTRFS_FILE_EXTENT_REG); 2945 if (!ret) 2946 btrfs_release_delalloc_bytes(root, 2947 ordered_extent->start, 2948 ordered_extent->disk_len); 2949 } 2950 unpin_extent_cache(&BTRFS_I(inode)->extent_tree, 2951 ordered_extent->file_offset, ordered_extent->len, 2952 trans->transid); 2953 if (ret < 0) { 2954 btrfs_abort_transaction(trans, root, ret); 2955 goto out_unlock; 2956 } 2957 2958 add_pending_csums(trans, inode, ordered_extent->file_offset, 2959 &ordered_extent->list); 2960 2961 btrfs_ordered_update_i_size(inode, 0, ordered_extent); 2962 ret = btrfs_update_inode_fallback(trans, root, inode); 2963 if (ret) { /* -ENOMEM or corruption */ 2964 btrfs_abort_transaction(trans, root, ret); 2965 goto out_unlock; 2966 } 2967 ret = 0; 2968 out_unlock: 2969 unlock_extent_cached(io_tree, ordered_extent->file_offset, 2970 ordered_extent->file_offset + 2971 ordered_extent->len - 1, &cached_state, GFP_NOFS); 2972 out: 2973 if (root != root->fs_info->tree_root) 2974 btrfs_delalloc_release_metadata(inode, ordered_extent->len); 2975 if (trans) 2976 btrfs_end_transaction(trans, root); 2977 2978 if (ret || truncated) { 2979 u64 start, end; 2980 2981 if (truncated) 2982 start = ordered_extent->file_offset + logical_len; 2983 else 2984 start = ordered_extent->file_offset; 2985 end = ordered_extent->file_offset + ordered_extent->len - 1; 2986 clear_extent_uptodate(io_tree, start, end, NULL, GFP_NOFS); 2987 2988 /* Drop the cache for the part of the extent we didn't write. */ 2989 btrfs_drop_extent_cache(inode, start, end, 0); 2990 2991 /* 2992 * If the ordered extent had an IOERR or something else went 2993 * wrong we need to return the space for this ordered extent 2994 * back to the allocator. We only free the extent in the 2995 * truncated case if we didn't write out the extent at all. 2996 */ 2997 if ((ret || !logical_len) && 2998 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && 2999 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) 3000 btrfs_free_reserved_extent(root, ordered_extent->start, 3001 ordered_extent->disk_len, 1); 3002 } 3003 3004 3005 /* 3006 * This needs to be done to make sure anybody waiting knows we are done 3007 * updating everything for this ordered extent. 3008 */ 3009 btrfs_remove_ordered_extent(inode, ordered_extent); 3010 3011 /* for snapshot-aware defrag */ 3012 if (new) { 3013 if (ret) { 3014 free_sa_defrag_extent(new); 3015 atomic_dec(&root->fs_info->defrag_running); 3016 } else { 3017 relink_file_extents(new); 3018 } 3019 } 3020 3021 /* once for us */ 3022 btrfs_put_ordered_extent(ordered_extent); 3023 /* once for the tree */ 3024 btrfs_put_ordered_extent(ordered_extent); 3025 3026 return ret; 3027 } 3028 3029 static void finish_ordered_fn(struct btrfs_work *work) 3030 { 3031 struct btrfs_ordered_extent *ordered_extent; 3032 ordered_extent = container_of(work, struct btrfs_ordered_extent, work); 3033 btrfs_finish_ordered_io(ordered_extent); 3034 } 3035 3036 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, 3037 struct extent_state *state, int uptodate) 3038 { 3039 struct inode *inode = page->mapping->host; 3040 struct btrfs_root *root = BTRFS_I(inode)->root; 3041 struct btrfs_ordered_extent *ordered_extent = NULL; 3042 struct btrfs_workqueue *wq; 3043 btrfs_work_func_t func; 3044 3045 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); 3046 3047 ClearPagePrivate2(page); 3048 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start, 3049 end - start + 1, uptodate)) 3050 return 0; 3051 3052 if (btrfs_is_free_space_inode(inode)) { 3053 wq = root->fs_info->endio_freespace_worker; 3054 func = btrfs_freespace_write_helper; 3055 } else { 3056 wq = root->fs_info->endio_write_workers; 3057 func = btrfs_endio_write_helper; 3058 } 3059 3060 btrfs_init_work(&ordered_extent->work, func, finish_ordered_fn, NULL, 3061 NULL); 3062 btrfs_queue_work(wq, &ordered_extent->work); 3063 3064 return 0; 3065 } 3066 3067 static int __readpage_endio_check(struct inode *inode, 3068 struct btrfs_io_bio *io_bio, 3069 int icsum, struct page *page, 3070 int pgoff, u64 start, size_t len) 3071 { 3072 char *kaddr; 3073 u32 csum_expected; 3074 u32 csum = ~(u32)0; 3075 3076 csum_expected = *(((u32 *)io_bio->csum) + icsum); 3077 3078 kaddr = kmap_atomic(page); 3079 csum = btrfs_csum_data(kaddr + pgoff, csum, len); 3080 btrfs_csum_final(csum, (char *)&csum); 3081 if (csum != csum_expected) 3082 goto zeroit; 3083 3084 kunmap_atomic(kaddr); 3085 return 0; 3086 zeroit: 3087 btrfs_warn_rl(BTRFS_I(inode)->root->fs_info, 3088 "csum failed ino %llu off %llu csum %u expected csum %u", 3089 btrfs_ino(inode), start, csum, csum_expected); 3090 memset(kaddr + pgoff, 1, len); 3091 flush_dcache_page(page); 3092 kunmap_atomic(kaddr); 3093 if (csum_expected == 0) 3094 return 0; 3095 return -EIO; 3096 } 3097 3098 /* 3099 * when reads are done, we need to check csums to verify the data is correct 3100 * if there's a match, we allow the bio to finish. If not, the code in 3101 * extent_io.c will try to find good copies for us. 3102 */ 3103 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio, 3104 u64 phy_offset, struct page *page, 3105 u64 start, u64 end, int mirror) 3106 { 3107 size_t offset = start - page_offset(page); 3108 struct inode *inode = page->mapping->host; 3109 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 3110 struct btrfs_root *root = BTRFS_I(inode)->root; 3111 3112 if (PageChecked(page)) { 3113 ClearPageChecked(page); 3114 return 0; 3115 } 3116 3117 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) 3118 return 0; 3119 3120 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && 3121 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { 3122 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM); 3123 return 0; 3124 } 3125 3126 phy_offset >>= inode->i_sb->s_blocksize_bits; 3127 return __readpage_endio_check(inode, io_bio, phy_offset, page, offset, 3128 start, (size_t)(end - start + 1)); 3129 } 3130 3131 void btrfs_add_delayed_iput(struct inode *inode) 3132 { 3133 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; 3134 struct btrfs_inode *binode = BTRFS_I(inode); 3135 3136 if (atomic_add_unless(&inode->i_count, -1, 1)) 3137 return; 3138 3139 spin_lock(&fs_info->delayed_iput_lock); 3140 if (binode->delayed_iput_count == 0) { 3141 ASSERT(list_empty(&binode->delayed_iput)); 3142 list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs); 3143 } else { 3144 binode->delayed_iput_count++; 3145 } 3146 spin_unlock(&fs_info->delayed_iput_lock); 3147 } 3148 3149 void btrfs_run_delayed_iputs(struct btrfs_root *root) 3150 { 3151 struct btrfs_fs_info *fs_info = root->fs_info; 3152 3153 spin_lock(&fs_info->delayed_iput_lock); 3154 while (!list_empty(&fs_info->delayed_iputs)) { 3155 struct btrfs_inode *inode; 3156 3157 inode = list_first_entry(&fs_info->delayed_iputs, 3158 struct btrfs_inode, delayed_iput); 3159 if (inode->delayed_iput_count) { 3160 inode->delayed_iput_count--; 3161 list_move_tail(&inode->delayed_iput, 3162 &fs_info->delayed_iputs); 3163 } else { 3164 list_del_init(&inode->delayed_iput); 3165 } 3166 spin_unlock(&fs_info->delayed_iput_lock); 3167 iput(&inode->vfs_inode); 3168 spin_lock(&fs_info->delayed_iput_lock); 3169 } 3170 spin_unlock(&fs_info->delayed_iput_lock); 3171 } 3172 3173 /* 3174 * This is called in transaction commit time. If there are no orphan 3175 * files in the subvolume, it removes orphan item and frees block_rsv 3176 * structure. 3177 */ 3178 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans, 3179 struct btrfs_root *root) 3180 { 3181 struct btrfs_block_rsv *block_rsv; 3182 int ret; 3183 3184 if (atomic_read(&root->orphan_inodes) || 3185 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) 3186 return; 3187 3188 spin_lock(&root->orphan_lock); 3189 if (atomic_read(&root->orphan_inodes)) { 3190 spin_unlock(&root->orphan_lock); 3191 return; 3192 } 3193 3194 if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) { 3195 spin_unlock(&root->orphan_lock); 3196 return; 3197 } 3198 3199 block_rsv = root->orphan_block_rsv; 3200 root->orphan_block_rsv = NULL; 3201 spin_unlock(&root->orphan_lock); 3202 3203 if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state) && 3204 btrfs_root_refs(&root->root_item) > 0) { 3205 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root, 3206 root->root_key.objectid); 3207 if (ret) 3208 btrfs_abort_transaction(trans, root, ret); 3209 else 3210 clear_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, 3211 &root->state); 3212 } 3213 3214 if (block_rsv) { 3215 WARN_ON(block_rsv->size > 0); 3216 btrfs_free_block_rsv(root, block_rsv); 3217 } 3218 } 3219 3220 /* 3221 * This creates an orphan entry for the given inode in case something goes 3222 * wrong in the middle of an unlink/truncate. 3223 * 3224 * NOTE: caller of this function should reserve 5 units of metadata for 3225 * this function. 3226 */ 3227 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode) 3228 { 3229 struct btrfs_root *root = BTRFS_I(inode)->root; 3230 struct btrfs_block_rsv *block_rsv = NULL; 3231 int reserve = 0; 3232 int insert = 0; 3233 int ret; 3234 3235 if (!root->orphan_block_rsv) { 3236 block_rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP); 3237 if (!block_rsv) 3238 return -ENOMEM; 3239 } 3240 3241 spin_lock(&root->orphan_lock); 3242 if (!root->orphan_block_rsv) { 3243 root->orphan_block_rsv = block_rsv; 3244 } else if (block_rsv) { 3245 btrfs_free_block_rsv(root, block_rsv); 3246 block_rsv = NULL; 3247 } 3248 3249 if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3250 &BTRFS_I(inode)->runtime_flags)) { 3251 #if 0 3252 /* 3253 * For proper ENOSPC handling, we should do orphan 3254 * cleanup when mounting. But this introduces backward 3255 * compatibility issue. 3256 */ 3257 if (!xchg(&root->orphan_item_inserted, 1)) 3258 insert = 2; 3259 else 3260 insert = 1; 3261 #endif 3262 insert = 1; 3263 atomic_inc(&root->orphan_inodes); 3264 } 3265 3266 if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3267 &BTRFS_I(inode)->runtime_flags)) 3268 reserve = 1; 3269 spin_unlock(&root->orphan_lock); 3270 3271 /* grab metadata reservation from transaction handle */ 3272 if (reserve) { 3273 ret = btrfs_orphan_reserve_metadata(trans, inode); 3274 ASSERT(!ret); 3275 if (ret) { 3276 atomic_dec(&root->orphan_inodes); 3277 clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3278 &BTRFS_I(inode)->runtime_flags); 3279 if (insert) 3280 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3281 &BTRFS_I(inode)->runtime_flags); 3282 return ret; 3283 } 3284 } 3285 3286 /* insert an orphan item to track this unlinked/truncated file */ 3287 if (insert >= 1) { 3288 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode)); 3289 if (ret) { 3290 atomic_dec(&root->orphan_inodes); 3291 if (reserve) { 3292 clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3293 &BTRFS_I(inode)->runtime_flags); 3294 btrfs_orphan_release_metadata(inode); 3295 } 3296 if (ret != -EEXIST) { 3297 clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3298 &BTRFS_I(inode)->runtime_flags); 3299 btrfs_abort_transaction(trans, root, ret); 3300 return ret; 3301 } 3302 } 3303 ret = 0; 3304 } 3305 3306 /* insert an orphan item to track subvolume contains orphan files */ 3307 if (insert >= 2) { 3308 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root, 3309 root->root_key.objectid); 3310 if (ret && ret != -EEXIST) { 3311 btrfs_abort_transaction(trans, root, ret); 3312 return ret; 3313 } 3314 } 3315 return 0; 3316 } 3317 3318 /* 3319 * We have done the truncate/delete so we can go ahead and remove the orphan 3320 * item for this particular inode. 3321 */ 3322 static int btrfs_orphan_del(struct btrfs_trans_handle *trans, 3323 struct inode *inode) 3324 { 3325 struct btrfs_root *root = BTRFS_I(inode)->root; 3326 int delete_item = 0; 3327 int release_rsv = 0; 3328 int ret = 0; 3329 3330 spin_lock(&root->orphan_lock); 3331 if (test_and_clear_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3332 &BTRFS_I(inode)->runtime_flags)) 3333 delete_item = 1; 3334 3335 if (test_and_clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED, 3336 &BTRFS_I(inode)->runtime_flags)) 3337 release_rsv = 1; 3338 spin_unlock(&root->orphan_lock); 3339 3340 if (delete_item) { 3341 atomic_dec(&root->orphan_inodes); 3342 if (trans) 3343 ret = btrfs_del_orphan_item(trans, root, 3344 btrfs_ino(inode)); 3345 } 3346 3347 if (release_rsv) 3348 btrfs_orphan_release_metadata(inode); 3349 3350 return ret; 3351 } 3352 3353 /* 3354 * this cleans up any orphans that may be left on the list from the last use 3355 * of this root. 3356 */ 3357 int btrfs_orphan_cleanup(struct btrfs_root *root) 3358 { 3359 struct btrfs_path *path; 3360 struct extent_buffer *leaf; 3361 struct btrfs_key key, found_key; 3362 struct btrfs_trans_handle *trans; 3363 struct inode *inode; 3364 u64 last_objectid = 0; 3365 int ret = 0, nr_unlink = 0, nr_truncate = 0; 3366 3367 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED)) 3368 return 0; 3369 3370 path = btrfs_alloc_path(); 3371 if (!path) { 3372 ret = -ENOMEM; 3373 goto out; 3374 } 3375 path->reada = READA_BACK; 3376 3377 key.objectid = BTRFS_ORPHAN_OBJECTID; 3378 key.type = BTRFS_ORPHAN_ITEM_KEY; 3379 key.offset = (u64)-1; 3380 3381 while (1) { 3382 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3383 if (ret < 0) 3384 goto out; 3385 3386 /* 3387 * if ret == 0 means we found what we were searching for, which 3388 * is weird, but possible, so only screw with path if we didn't 3389 * find the key and see if we have stuff that matches 3390 */ 3391 if (ret > 0) { 3392 ret = 0; 3393 if (path->slots[0] == 0) 3394 break; 3395 path->slots[0]--; 3396 } 3397 3398 /* pull out the item */ 3399 leaf = path->nodes[0]; 3400 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 3401 3402 /* make sure the item matches what we want */ 3403 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) 3404 break; 3405 if (found_key.type != BTRFS_ORPHAN_ITEM_KEY) 3406 break; 3407 3408 /* release the path since we're done with it */ 3409 btrfs_release_path(path); 3410 3411 /* 3412 * this is where we are basically btrfs_lookup, without the 3413 * crossing root thing. we store the inode number in the 3414 * offset of the orphan item. 3415 */ 3416 3417 if (found_key.offset == last_objectid) { 3418 btrfs_err(root->fs_info, 3419 "Error removing orphan entry, stopping orphan cleanup"); 3420 ret = -EINVAL; 3421 goto out; 3422 } 3423 3424 last_objectid = found_key.offset; 3425 3426 found_key.objectid = found_key.offset; 3427 found_key.type = BTRFS_INODE_ITEM_KEY; 3428 found_key.offset = 0; 3429 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL); 3430 ret = PTR_ERR_OR_ZERO(inode); 3431 if (ret && ret != -ESTALE) 3432 goto out; 3433 3434 if (ret == -ESTALE && root == root->fs_info->tree_root) { 3435 struct btrfs_root *dead_root; 3436 struct btrfs_fs_info *fs_info = root->fs_info; 3437 int is_dead_root = 0; 3438 3439 /* 3440 * this is an orphan in the tree root. Currently these 3441 * could come from 2 sources: 3442 * a) a snapshot deletion in progress 3443 * b) a free space cache inode 3444 * We need to distinguish those two, as the snapshot 3445 * orphan must not get deleted. 3446 * find_dead_roots already ran before us, so if this 3447 * is a snapshot deletion, we should find the root 3448 * in the dead_roots list 3449 */ 3450 spin_lock(&fs_info->trans_lock); 3451 list_for_each_entry(dead_root, &fs_info->dead_roots, 3452 root_list) { 3453 if (dead_root->root_key.objectid == 3454 found_key.objectid) { 3455 is_dead_root = 1; 3456 break; 3457 } 3458 } 3459 spin_unlock(&fs_info->trans_lock); 3460 if (is_dead_root) { 3461 /* prevent this orphan from being found again */ 3462 key.offset = found_key.objectid - 1; 3463 continue; 3464 } 3465 } 3466 /* 3467 * Inode is already gone but the orphan item is still there, 3468 * kill the orphan item. 3469 */ 3470 if (ret == -ESTALE) { 3471 trans = btrfs_start_transaction(root, 1); 3472 if (IS_ERR(trans)) { 3473 ret = PTR_ERR(trans); 3474 goto out; 3475 } 3476 btrfs_debug(root->fs_info, "auto deleting %Lu", 3477 found_key.objectid); 3478 ret = btrfs_del_orphan_item(trans, root, 3479 found_key.objectid); 3480 btrfs_end_transaction(trans, root); 3481 if (ret) 3482 goto out; 3483 continue; 3484 } 3485 3486 /* 3487 * add this inode to the orphan list so btrfs_orphan_del does 3488 * the proper thing when we hit it 3489 */ 3490 set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 3491 &BTRFS_I(inode)->runtime_flags); 3492 atomic_inc(&root->orphan_inodes); 3493 3494 /* if we have links, this was a truncate, lets do that */ 3495 if (inode->i_nlink) { 3496 if (WARN_ON(!S_ISREG(inode->i_mode))) { 3497 iput(inode); 3498 continue; 3499 } 3500 nr_truncate++; 3501 3502 /* 1 for the orphan item deletion. */ 3503 trans = btrfs_start_transaction(root, 1); 3504 if (IS_ERR(trans)) { 3505 iput(inode); 3506 ret = PTR_ERR(trans); 3507 goto out; 3508 } 3509 ret = btrfs_orphan_add(trans, inode); 3510 btrfs_end_transaction(trans, root); 3511 if (ret) { 3512 iput(inode); 3513 goto out; 3514 } 3515 3516 ret = btrfs_truncate(inode); 3517 if (ret) 3518 btrfs_orphan_del(NULL, inode); 3519 } else { 3520 nr_unlink++; 3521 } 3522 3523 /* this will do delete_inode and everything for us */ 3524 iput(inode); 3525 if (ret) 3526 goto out; 3527 } 3528 /* release the path since we're done with it */ 3529 btrfs_release_path(path); 3530 3531 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE; 3532 3533 if (root->orphan_block_rsv) 3534 btrfs_block_rsv_release(root, root->orphan_block_rsv, 3535 (u64)-1); 3536 3537 if (root->orphan_block_rsv || 3538 test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) { 3539 trans = btrfs_join_transaction(root); 3540 if (!IS_ERR(trans)) 3541 btrfs_end_transaction(trans, root); 3542 } 3543 3544 if (nr_unlink) 3545 btrfs_debug(root->fs_info, "unlinked %d orphans", nr_unlink); 3546 if (nr_truncate) 3547 btrfs_debug(root->fs_info, "truncated %d orphans", nr_truncate); 3548 3549 out: 3550 if (ret) 3551 btrfs_err(root->fs_info, 3552 "could not do orphan cleanup %d", ret); 3553 btrfs_free_path(path); 3554 return ret; 3555 } 3556 3557 /* 3558 * very simple check to peek ahead in the leaf looking for xattrs. If we 3559 * don't find any xattrs, we know there can't be any acls. 3560 * 3561 * slot is the slot the inode is in, objectid is the objectid of the inode 3562 */ 3563 static noinline int acls_after_inode_item(struct extent_buffer *leaf, 3564 int slot, u64 objectid, 3565 int *first_xattr_slot) 3566 { 3567 u32 nritems = btrfs_header_nritems(leaf); 3568 struct btrfs_key found_key; 3569 static u64 xattr_access = 0; 3570 static u64 xattr_default = 0; 3571 int scanned = 0; 3572 3573 if (!xattr_access) { 3574 xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS, 3575 strlen(XATTR_NAME_POSIX_ACL_ACCESS)); 3576 xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT, 3577 strlen(XATTR_NAME_POSIX_ACL_DEFAULT)); 3578 } 3579 3580 slot++; 3581 *first_xattr_slot = -1; 3582 while (slot < nritems) { 3583 btrfs_item_key_to_cpu(leaf, &found_key, slot); 3584 3585 /* we found a different objectid, there must not be acls */ 3586 if (found_key.objectid != objectid) 3587 return 0; 3588 3589 /* we found an xattr, assume we've got an acl */ 3590 if (found_key.type == BTRFS_XATTR_ITEM_KEY) { 3591 if (*first_xattr_slot == -1) 3592 *first_xattr_slot = slot; 3593 if (found_key.offset == xattr_access || 3594 found_key.offset == xattr_default) 3595 return 1; 3596 } 3597 3598 /* 3599 * we found a key greater than an xattr key, there can't 3600 * be any acls later on 3601 */ 3602 if (found_key.type > BTRFS_XATTR_ITEM_KEY) 3603 return 0; 3604 3605 slot++; 3606 scanned++; 3607 3608 /* 3609 * it goes inode, inode backrefs, xattrs, extents, 3610 * so if there are a ton of hard links to an inode there can 3611 * be a lot of backrefs. Don't waste time searching too hard, 3612 * this is just an optimization 3613 */ 3614 if (scanned >= 8) 3615 break; 3616 } 3617 /* we hit the end of the leaf before we found an xattr or 3618 * something larger than an xattr. We have to assume the inode 3619 * has acls 3620 */ 3621 if (*first_xattr_slot == -1) 3622 *first_xattr_slot = slot; 3623 return 1; 3624 } 3625 3626 /* 3627 * read an inode from the btree into the in-memory inode 3628 */ 3629 static void btrfs_read_locked_inode(struct inode *inode) 3630 { 3631 struct btrfs_path *path; 3632 struct extent_buffer *leaf; 3633 struct btrfs_inode_item *inode_item; 3634 struct btrfs_root *root = BTRFS_I(inode)->root; 3635 struct btrfs_key location; 3636 unsigned long ptr; 3637 int maybe_acls; 3638 u32 rdev; 3639 int ret; 3640 bool filled = false; 3641 int first_xattr_slot; 3642 3643 ret = btrfs_fill_inode(inode, &rdev); 3644 if (!ret) 3645 filled = true; 3646 3647 path = btrfs_alloc_path(); 3648 if (!path) 3649 goto make_bad; 3650 3651 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location)); 3652 3653 ret = btrfs_lookup_inode(NULL, root, path, &location, 0); 3654 if (ret) 3655 goto make_bad; 3656 3657 leaf = path->nodes[0]; 3658 3659 if (filled) 3660 goto cache_index; 3661 3662 inode_item = btrfs_item_ptr(leaf, path->slots[0], 3663 struct btrfs_inode_item); 3664 inode->i_mode = btrfs_inode_mode(leaf, inode_item); 3665 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item)); 3666 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item)); 3667 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item)); 3668 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item)); 3669 3670 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->atime); 3671 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->atime); 3672 3673 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->mtime); 3674 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->mtime); 3675 3676 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime); 3677 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime); 3678 3679 BTRFS_I(inode)->i_otime.tv_sec = 3680 btrfs_timespec_sec(leaf, &inode_item->otime); 3681 BTRFS_I(inode)->i_otime.tv_nsec = 3682 btrfs_timespec_nsec(leaf, &inode_item->otime); 3683 3684 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item)); 3685 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item); 3686 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item); 3687 3688 inode->i_version = btrfs_inode_sequence(leaf, inode_item); 3689 inode->i_generation = BTRFS_I(inode)->generation; 3690 inode->i_rdev = 0; 3691 rdev = btrfs_inode_rdev(leaf, inode_item); 3692 3693 BTRFS_I(inode)->index_cnt = (u64)-1; 3694 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item); 3695 3696 cache_index: 3697 /* 3698 * If we were modified in the current generation and evicted from memory 3699 * and then re-read we need to do a full sync since we don't have any 3700 * idea about which extents were modified before we were evicted from 3701 * cache. 3702 * 3703 * This is required for both inode re-read from disk and delayed inode 3704 * in delayed_nodes_tree. 3705 */ 3706 if (BTRFS_I(inode)->last_trans == root->fs_info->generation) 3707 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3708 &BTRFS_I(inode)->runtime_flags); 3709 3710 /* 3711 * We don't persist the id of the transaction where an unlink operation 3712 * against the inode was last made. So here we assume the inode might 3713 * have been evicted, and therefore the exact value of last_unlink_trans 3714 * lost, and set it to last_trans to avoid metadata inconsistencies 3715 * between the inode and its parent if the inode is fsync'ed and the log 3716 * replayed. For example, in the scenario: 3717 * 3718 * touch mydir/foo 3719 * ln mydir/foo mydir/bar 3720 * sync 3721 * unlink mydir/bar 3722 * echo 2 > /proc/sys/vm/drop_caches # evicts inode 3723 * xfs_io -c fsync mydir/foo 3724 * <power failure> 3725 * mount fs, triggers fsync log replay 3726 * 3727 * We must make sure that when we fsync our inode foo we also log its 3728 * parent inode, otherwise after log replay the parent still has the 3729 * dentry with the "bar" name but our inode foo has a link count of 1 3730 * and doesn't have an inode ref with the name "bar" anymore. 3731 * 3732 * Setting last_unlink_trans to last_trans is a pessimistic approach, 3733 * but it guarantees correctness at the expense of occasional full 3734 * transaction commits on fsync if our inode is a directory, or if our 3735 * inode is not a directory, logging its parent unnecessarily. 3736 */ 3737 BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans; 3738 3739 path->slots[0]++; 3740 if (inode->i_nlink != 1 || 3741 path->slots[0] >= btrfs_header_nritems(leaf)) 3742 goto cache_acl; 3743 3744 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]); 3745 if (location.objectid != btrfs_ino(inode)) 3746 goto cache_acl; 3747 3748 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); 3749 if (location.type == BTRFS_INODE_REF_KEY) { 3750 struct btrfs_inode_ref *ref; 3751 3752 ref = (struct btrfs_inode_ref *)ptr; 3753 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref); 3754 } else if (location.type == BTRFS_INODE_EXTREF_KEY) { 3755 struct btrfs_inode_extref *extref; 3756 3757 extref = (struct btrfs_inode_extref *)ptr; 3758 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf, 3759 extref); 3760 } 3761 cache_acl: 3762 /* 3763 * try to precache a NULL acl entry for files that don't have 3764 * any xattrs or acls 3765 */ 3766 maybe_acls = acls_after_inode_item(leaf, path->slots[0], 3767 btrfs_ino(inode), &first_xattr_slot); 3768 if (first_xattr_slot != -1) { 3769 path->slots[0] = first_xattr_slot; 3770 ret = btrfs_load_inode_props(inode, path); 3771 if (ret) 3772 btrfs_err(root->fs_info, 3773 "error loading props for ino %llu (root %llu): %d", 3774 btrfs_ino(inode), 3775 root->root_key.objectid, ret); 3776 } 3777 btrfs_free_path(path); 3778 3779 if (!maybe_acls) 3780 cache_no_acl(inode); 3781 3782 switch (inode->i_mode & S_IFMT) { 3783 case S_IFREG: 3784 inode->i_mapping->a_ops = &btrfs_aops; 3785 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 3786 inode->i_fop = &btrfs_file_operations; 3787 inode->i_op = &btrfs_file_inode_operations; 3788 break; 3789 case S_IFDIR: 3790 inode->i_fop = &btrfs_dir_file_operations; 3791 if (root == root->fs_info->tree_root) 3792 inode->i_op = &btrfs_dir_ro_inode_operations; 3793 else 3794 inode->i_op = &btrfs_dir_inode_operations; 3795 break; 3796 case S_IFLNK: 3797 inode->i_op = &btrfs_symlink_inode_operations; 3798 inode_nohighmem(inode); 3799 inode->i_mapping->a_ops = &btrfs_symlink_aops; 3800 break; 3801 default: 3802 inode->i_op = &btrfs_special_inode_operations; 3803 init_special_inode(inode, inode->i_mode, rdev); 3804 break; 3805 } 3806 3807 btrfs_update_iflags(inode); 3808 return; 3809 3810 make_bad: 3811 btrfs_free_path(path); 3812 make_bad_inode(inode); 3813 } 3814 3815 /* 3816 * given a leaf and an inode, copy the inode fields into the leaf 3817 */ 3818 static void fill_inode_item(struct btrfs_trans_handle *trans, 3819 struct extent_buffer *leaf, 3820 struct btrfs_inode_item *item, 3821 struct inode *inode) 3822 { 3823 struct btrfs_map_token token; 3824 3825 btrfs_init_map_token(&token); 3826 3827 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token); 3828 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token); 3829 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size, 3830 &token); 3831 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token); 3832 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token); 3833 3834 btrfs_set_token_timespec_sec(leaf, &item->atime, 3835 inode->i_atime.tv_sec, &token); 3836 btrfs_set_token_timespec_nsec(leaf, &item->atime, 3837 inode->i_atime.tv_nsec, &token); 3838 3839 btrfs_set_token_timespec_sec(leaf, &item->mtime, 3840 inode->i_mtime.tv_sec, &token); 3841 btrfs_set_token_timespec_nsec(leaf, &item->mtime, 3842 inode->i_mtime.tv_nsec, &token); 3843 3844 btrfs_set_token_timespec_sec(leaf, &item->ctime, 3845 inode->i_ctime.tv_sec, &token); 3846 btrfs_set_token_timespec_nsec(leaf, &item->ctime, 3847 inode->i_ctime.tv_nsec, &token); 3848 3849 btrfs_set_token_timespec_sec(leaf, &item->otime, 3850 BTRFS_I(inode)->i_otime.tv_sec, &token); 3851 btrfs_set_token_timespec_nsec(leaf, &item->otime, 3852 BTRFS_I(inode)->i_otime.tv_nsec, &token); 3853 3854 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode), 3855 &token); 3856 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation, 3857 &token); 3858 btrfs_set_token_inode_sequence(leaf, item, inode->i_version, &token); 3859 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token); 3860 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token); 3861 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token); 3862 btrfs_set_token_inode_block_group(leaf, item, 0, &token); 3863 } 3864 3865 /* 3866 * copy everything in the in-memory inode into the btree. 3867 */ 3868 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans, 3869 struct btrfs_root *root, struct inode *inode) 3870 { 3871 struct btrfs_inode_item *inode_item; 3872 struct btrfs_path *path; 3873 struct extent_buffer *leaf; 3874 int ret; 3875 3876 path = btrfs_alloc_path(); 3877 if (!path) 3878 return -ENOMEM; 3879 3880 path->leave_spinning = 1; 3881 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location, 3882 1); 3883 if (ret) { 3884 if (ret > 0) 3885 ret = -ENOENT; 3886 goto failed; 3887 } 3888 3889 leaf = path->nodes[0]; 3890 inode_item = btrfs_item_ptr(leaf, path->slots[0], 3891 struct btrfs_inode_item); 3892 3893 fill_inode_item(trans, leaf, inode_item, inode); 3894 btrfs_mark_buffer_dirty(leaf); 3895 btrfs_set_inode_last_trans(trans, inode); 3896 ret = 0; 3897 failed: 3898 btrfs_free_path(path); 3899 return ret; 3900 } 3901 3902 /* 3903 * copy everything in the in-memory inode into the btree. 3904 */ 3905 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans, 3906 struct btrfs_root *root, struct inode *inode) 3907 { 3908 int ret; 3909 3910 /* 3911 * If the inode is a free space inode, we can deadlock during commit 3912 * if we put it into the delayed code. 3913 * 3914 * The data relocation inode should also be directly updated 3915 * without delay 3916 */ 3917 if (!btrfs_is_free_space_inode(inode) 3918 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID 3919 && !root->fs_info->log_root_recovering) { 3920 btrfs_update_root_times(trans, root); 3921 3922 ret = btrfs_delayed_update_inode(trans, root, inode); 3923 if (!ret) 3924 btrfs_set_inode_last_trans(trans, inode); 3925 return ret; 3926 } 3927 3928 return btrfs_update_inode_item(trans, root, inode); 3929 } 3930 3931 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, 3932 struct btrfs_root *root, 3933 struct inode *inode) 3934 { 3935 int ret; 3936 3937 ret = btrfs_update_inode(trans, root, inode); 3938 if (ret == -ENOSPC) 3939 return btrfs_update_inode_item(trans, root, inode); 3940 return ret; 3941 } 3942 3943 /* 3944 * unlink helper that gets used here in inode.c and in the tree logging 3945 * recovery code. It remove a link in a directory with a given name, and 3946 * also drops the back refs in the inode to the directory 3947 */ 3948 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans, 3949 struct btrfs_root *root, 3950 struct inode *dir, struct inode *inode, 3951 const char *name, int name_len) 3952 { 3953 struct btrfs_path *path; 3954 int ret = 0; 3955 struct extent_buffer *leaf; 3956 struct btrfs_dir_item *di; 3957 struct btrfs_key key; 3958 u64 index; 3959 u64 ino = btrfs_ino(inode); 3960 u64 dir_ino = btrfs_ino(dir); 3961 3962 path = btrfs_alloc_path(); 3963 if (!path) { 3964 ret = -ENOMEM; 3965 goto out; 3966 } 3967 3968 path->leave_spinning = 1; 3969 di = btrfs_lookup_dir_item(trans, root, path, dir_ino, 3970 name, name_len, -1); 3971 if (IS_ERR(di)) { 3972 ret = PTR_ERR(di); 3973 goto err; 3974 } 3975 if (!di) { 3976 ret = -ENOENT; 3977 goto err; 3978 } 3979 leaf = path->nodes[0]; 3980 btrfs_dir_item_key_to_cpu(leaf, di, &key); 3981 ret = btrfs_delete_one_dir_name(trans, root, path, di); 3982 if (ret) 3983 goto err; 3984 btrfs_release_path(path); 3985 3986 /* 3987 * If we don't have dir index, we have to get it by looking up 3988 * the inode ref, since we get the inode ref, remove it directly, 3989 * it is unnecessary to do delayed deletion. 3990 * 3991 * But if we have dir index, needn't search inode ref to get it. 3992 * Since the inode ref is close to the inode item, it is better 3993 * that we delay to delete it, and just do this deletion when 3994 * we update the inode item. 3995 */ 3996 if (BTRFS_I(inode)->dir_index) { 3997 ret = btrfs_delayed_delete_inode_ref(inode); 3998 if (!ret) { 3999 index = BTRFS_I(inode)->dir_index; 4000 goto skip_backref; 4001 } 4002 } 4003 4004 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino, 4005 dir_ino, &index); 4006 if (ret) { 4007 btrfs_info(root->fs_info, 4008 "failed to delete reference to %.*s, inode %llu parent %llu", 4009 name_len, name, ino, dir_ino); 4010 btrfs_abort_transaction(trans, root, ret); 4011 goto err; 4012 } 4013 skip_backref: 4014 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index); 4015 if (ret) { 4016 btrfs_abort_transaction(trans, root, ret); 4017 goto err; 4018 } 4019 4020 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, 4021 inode, dir_ino); 4022 if (ret != 0 && ret != -ENOENT) { 4023 btrfs_abort_transaction(trans, root, ret); 4024 goto err; 4025 } 4026 4027 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, 4028 dir, index); 4029 if (ret == -ENOENT) 4030 ret = 0; 4031 else if (ret) 4032 btrfs_abort_transaction(trans, root, ret); 4033 err: 4034 btrfs_free_path(path); 4035 if (ret) 4036 goto out; 4037 4038 btrfs_i_size_write(dir, dir->i_size - name_len * 2); 4039 inode_inc_iversion(inode); 4040 inode_inc_iversion(dir); 4041 inode->i_ctime = dir->i_mtime = 4042 dir->i_ctime = current_fs_time(inode->i_sb); 4043 ret = btrfs_update_inode(trans, root, dir); 4044 out: 4045 return ret; 4046 } 4047 4048 int btrfs_unlink_inode(struct btrfs_trans_handle *trans, 4049 struct btrfs_root *root, 4050 struct inode *dir, struct inode *inode, 4051 const char *name, int name_len) 4052 { 4053 int ret; 4054 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len); 4055 if (!ret) { 4056 drop_nlink(inode); 4057 ret = btrfs_update_inode(trans, root, inode); 4058 } 4059 return ret; 4060 } 4061 4062 /* 4063 * helper to start transaction for unlink and rmdir. 4064 * 4065 * unlink and rmdir are special in btrfs, they do not always free space, so 4066 * if we cannot make our reservations the normal way try and see if there is 4067 * plenty of slack room in the global reserve to migrate, otherwise we cannot 4068 * allow the unlink to occur. 4069 */ 4070 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir) 4071 { 4072 struct btrfs_root *root = BTRFS_I(dir)->root; 4073 4074 /* 4075 * 1 for the possible orphan item 4076 * 1 for the dir item 4077 * 1 for the dir index 4078 * 1 for the inode ref 4079 * 1 for the inode 4080 */ 4081 return btrfs_start_transaction_fallback_global_rsv(root, 5, 5); 4082 } 4083 4084 static int btrfs_unlink(struct inode *dir, struct dentry *dentry) 4085 { 4086 struct btrfs_root *root = BTRFS_I(dir)->root; 4087 struct btrfs_trans_handle *trans; 4088 struct inode *inode = d_inode(dentry); 4089 int ret; 4090 4091 trans = __unlink_start_trans(dir); 4092 if (IS_ERR(trans)) 4093 return PTR_ERR(trans); 4094 4095 btrfs_record_unlink_dir(trans, dir, d_inode(dentry), 0); 4096 4097 ret = btrfs_unlink_inode(trans, root, dir, d_inode(dentry), 4098 dentry->d_name.name, dentry->d_name.len); 4099 if (ret) 4100 goto out; 4101 4102 if (inode->i_nlink == 0) { 4103 ret = btrfs_orphan_add(trans, inode); 4104 if (ret) 4105 goto out; 4106 } 4107 4108 out: 4109 btrfs_end_transaction(trans, root); 4110 btrfs_btree_balance_dirty(root); 4111 return ret; 4112 } 4113 4114 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, 4115 struct btrfs_root *root, 4116 struct inode *dir, u64 objectid, 4117 const char *name, int name_len) 4118 { 4119 struct btrfs_path *path; 4120 struct extent_buffer *leaf; 4121 struct btrfs_dir_item *di; 4122 struct btrfs_key key; 4123 u64 index; 4124 int ret; 4125 u64 dir_ino = btrfs_ino(dir); 4126 4127 path = btrfs_alloc_path(); 4128 if (!path) 4129 return -ENOMEM; 4130 4131 di = btrfs_lookup_dir_item(trans, root, path, dir_ino, 4132 name, name_len, -1); 4133 if (IS_ERR_OR_NULL(di)) { 4134 if (!di) 4135 ret = -ENOENT; 4136 else 4137 ret = PTR_ERR(di); 4138 goto out; 4139 } 4140 4141 leaf = path->nodes[0]; 4142 btrfs_dir_item_key_to_cpu(leaf, di, &key); 4143 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); 4144 ret = btrfs_delete_one_dir_name(trans, root, path, di); 4145 if (ret) { 4146 btrfs_abort_transaction(trans, root, ret); 4147 goto out; 4148 } 4149 btrfs_release_path(path); 4150 4151 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root, 4152 objectid, root->root_key.objectid, 4153 dir_ino, &index, name, name_len); 4154 if (ret < 0) { 4155 if (ret != -ENOENT) { 4156 btrfs_abort_transaction(trans, root, ret); 4157 goto out; 4158 } 4159 di = btrfs_search_dir_index_item(root, path, dir_ino, 4160 name, name_len); 4161 if (IS_ERR_OR_NULL(di)) { 4162 if (!di) 4163 ret = -ENOENT; 4164 else 4165 ret = PTR_ERR(di); 4166 btrfs_abort_transaction(trans, root, ret); 4167 goto out; 4168 } 4169 4170 leaf = path->nodes[0]; 4171 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 4172 btrfs_release_path(path); 4173 index = key.offset; 4174 } 4175 btrfs_release_path(path); 4176 4177 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index); 4178 if (ret) { 4179 btrfs_abort_transaction(trans, root, ret); 4180 goto out; 4181 } 4182 4183 btrfs_i_size_write(dir, dir->i_size - name_len * 2); 4184 inode_inc_iversion(dir); 4185 dir->i_mtime = dir->i_ctime = current_fs_time(dir->i_sb); 4186 ret = btrfs_update_inode_fallback(trans, root, dir); 4187 if (ret) 4188 btrfs_abort_transaction(trans, root, ret); 4189 out: 4190 btrfs_free_path(path); 4191 return ret; 4192 } 4193 4194 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) 4195 { 4196 struct inode *inode = d_inode(dentry); 4197 int err = 0; 4198 struct btrfs_root *root = BTRFS_I(dir)->root; 4199 struct btrfs_trans_handle *trans; 4200 4201 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) 4202 return -ENOTEMPTY; 4203 if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID) 4204 return -EPERM; 4205 4206 trans = __unlink_start_trans(dir); 4207 if (IS_ERR(trans)) 4208 return PTR_ERR(trans); 4209 4210 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { 4211 err = btrfs_unlink_subvol(trans, root, dir, 4212 BTRFS_I(inode)->location.objectid, 4213 dentry->d_name.name, 4214 dentry->d_name.len); 4215 goto out; 4216 } 4217 4218 err = btrfs_orphan_add(trans, inode); 4219 if (err) 4220 goto out; 4221 4222 /* now the directory is empty */ 4223 err = btrfs_unlink_inode(trans, root, dir, d_inode(dentry), 4224 dentry->d_name.name, dentry->d_name.len); 4225 if (!err) 4226 btrfs_i_size_write(inode, 0); 4227 out: 4228 btrfs_end_transaction(trans, root); 4229 btrfs_btree_balance_dirty(root); 4230 4231 return err; 4232 } 4233 4234 static int truncate_space_check(struct btrfs_trans_handle *trans, 4235 struct btrfs_root *root, 4236 u64 bytes_deleted) 4237 { 4238 int ret; 4239 4240 /* 4241 * This is only used to apply pressure to the enospc system, we don't 4242 * intend to use this reservation at all. 4243 */ 4244 bytes_deleted = btrfs_csum_bytes_to_leaves(root, bytes_deleted); 4245 bytes_deleted *= root->nodesize; 4246 ret = btrfs_block_rsv_add(root, &root->fs_info->trans_block_rsv, 4247 bytes_deleted, BTRFS_RESERVE_NO_FLUSH); 4248 if (!ret) { 4249 trace_btrfs_space_reservation(root->fs_info, "transaction", 4250 trans->transid, 4251 bytes_deleted, 1); 4252 trans->bytes_reserved += bytes_deleted; 4253 } 4254 return ret; 4255 4256 } 4257 4258 static int truncate_inline_extent(struct inode *inode, 4259 struct btrfs_path *path, 4260 struct btrfs_key *found_key, 4261 const u64 item_end, 4262 const u64 new_size) 4263 { 4264 struct extent_buffer *leaf = path->nodes[0]; 4265 int slot = path->slots[0]; 4266 struct btrfs_file_extent_item *fi; 4267 u32 size = (u32)(new_size - found_key->offset); 4268 struct btrfs_root *root = BTRFS_I(inode)->root; 4269 4270 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); 4271 4272 if (btrfs_file_extent_compression(leaf, fi) != BTRFS_COMPRESS_NONE) { 4273 loff_t offset = new_size; 4274 loff_t page_end = ALIGN(offset, PAGE_SIZE); 4275 4276 /* 4277 * Zero out the remaining of the last page of our inline extent, 4278 * instead of directly truncating our inline extent here - that 4279 * would be much more complex (decompressing all the data, then 4280 * compressing the truncated data, which might be bigger than 4281 * the size of the inline extent, resize the extent, etc). 4282 * We release the path because to get the page we might need to 4283 * read the extent item from disk (data not in the page cache). 4284 */ 4285 btrfs_release_path(path); 4286 return btrfs_truncate_block(inode, offset, page_end - offset, 4287 0); 4288 } 4289 4290 btrfs_set_file_extent_ram_bytes(leaf, fi, size); 4291 size = btrfs_file_extent_calc_inline_size(size); 4292 btrfs_truncate_item(root, path, size, 1); 4293 4294 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4295 inode_sub_bytes(inode, item_end + 1 - new_size); 4296 4297 return 0; 4298 } 4299 4300 /* 4301 * this can truncate away extent items, csum items and directory items. 4302 * It starts at a high offset and removes keys until it can't find 4303 * any higher than new_size 4304 * 4305 * csum items that cross the new i_size are truncated to the new size 4306 * as well. 4307 * 4308 * min_type is the minimum key type to truncate down to. If set to 0, this 4309 * will kill all the items on this inode, including the INODE_ITEM_KEY. 4310 */ 4311 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, 4312 struct btrfs_root *root, 4313 struct inode *inode, 4314 u64 new_size, u32 min_type) 4315 { 4316 struct btrfs_path *path; 4317 struct extent_buffer *leaf; 4318 struct btrfs_file_extent_item *fi; 4319 struct btrfs_key key; 4320 struct btrfs_key found_key; 4321 u64 extent_start = 0; 4322 u64 extent_num_bytes = 0; 4323 u64 extent_offset = 0; 4324 u64 item_end = 0; 4325 u64 last_size = new_size; 4326 u32 found_type = (u8)-1; 4327 int found_extent; 4328 int del_item; 4329 int pending_del_nr = 0; 4330 int pending_del_slot = 0; 4331 int extent_type = -1; 4332 int ret; 4333 int err = 0; 4334 u64 ino = btrfs_ino(inode); 4335 u64 bytes_deleted = 0; 4336 bool be_nice = 0; 4337 bool should_throttle = 0; 4338 bool should_end = 0; 4339 4340 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); 4341 4342 /* 4343 * for non-free space inodes and ref cows, we want to back off from 4344 * time to time 4345 */ 4346 if (!btrfs_is_free_space_inode(inode) && 4347 test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4348 be_nice = 1; 4349 4350 path = btrfs_alloc_path(); 4351 if (!path) 4352 return -ENOMEM; 4353 path->reada = READA_BACK; 4354 4355 /* 4356 * We want to drop from the next block forward in case this new size is 4357 * not block aligned since we will be keeping the last block of the 4358 * extent just the way it is. 4359 */ 4360 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || 4361 root == root->fs_info->tree_root) 4362 btrfs_drop_extent_cache(inode, ALIGN(new_size, 4363 root->sectorsize), (u64)-1, 0); 4364 4365 /* 4366 * This function is also used to drop the items in the log tree before 4367 * we relog the inode, so if root != BTRFS_I(inode)->root, it means 4368 * it is used to drop the loged items. So we shouldn't kill the delayed 4369 * items. 4370 */ 4371 if (min_type == 0 && root == BTRFS_I(inode)->root) 4372 btrfs_kill_delayed_inode_items(inode); 4373 4374 key.objectid = ino; 4375 key.offset = (u64)-1; 4376 key.type = (u8)-1; 4377 4378 search_again: 4379 /* 4380 * with a 16K leaf size and 128MB extents, you can actually queue 4381 * up a huge file in a single leaf. Most of the time that 4382 * bytes_deleted is > 0, it will be huge by the time we get here 4383 */ 4384 if (be_nice && bytes_deleted > SZ_32M) { 4385 if (btrfs_should_end_transaction(trans, root)) { 4386 err = -EAGAIN; 4387 goto error; 4388 } 4389 } 4390 4391 4392 path->leave_spinning = 1; 4393 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 4394 if (ret < 0) { 4395 err = ret; 4396 goto out; 4397 } 4398 4399 if (ret > 0) { 4400 /* there are no items in the tree for us to truncate, we're 4401 * done 4402 */ 4403 if (path->slots[0] == 0) 4404 goto out; 4405 path->slots[0]--; 4406 } 4407 4408 while (1) { 4409 fi = NULL; 4410 leaf = path->nodes[0]; 4411 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 4412 found_type = found_key.type; 4413 4414 if (found_key.objectid != ino) 4415 break; 4416 4417 if (found_type < min_type) 4418 break; 4419 4420 item_end = found_key.offset; 4421 if (found_type == BTRFS_EXTENT_DATA_KEY) { 4422 fi = btrfs_item_ptr(leaf, path->slots[0], 4423 struct btrfs_file_extent_item); 4424 extent_type = btrfs_file_extent_type(leaf, fi); 4425 if (extent_type != BTRFS_FILE_EXTENT_INLINE) { 4426 item_end += 4427 btrfs_file_extent_num_bytes(leaf, fi); 4428 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 4429 item_end += btrfs_file_extent_inline_len(leaf, 4430 path->slots[0], fi); 4431 } 4432 item_end--; 4433 } 4434 if (found_type > min_type) { 4435 del_item = 1; 4436 } else { 4437 if (item_end < new_size) 4438 break; 4439 if (found_key.offset >= new_size) 4440 del_item = 1; 4441 else 4442 del_item = 0; 4443 } 4444 found_extent = 0; 4445 /* FIXME, shrink the extent if the ref count is only 1 */ 4446 if (found_type != BTRFS_EXTENT_DATA_KEY) 4447 goto delete; 4448 4449 if (del_item) 4450 last_size = found_key.offset; 4451 else 4452 last_size = new_size; 4453 4454 if (extent_type != BTRFS_FILE_EXTENT_INLINE) { 4455 u64 num_dec; 4456 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi); 4457 if (!del_item) { 4458 u64 orig_num_bytes = 4459 btrfs_file_extent_num_bytes(leaf, fi); 4460 extent_num_bytes = ALIGN(new_size - 4461 found_key.offset, 4462 root->sectorsize); 4463 btrfs_set_file_extent_num_bytes(leaf, fi, 4464 extent_num_bytes); 4465 num_dec = (orig_num_bytes - 4466 extent_num_bytes); 4467 if (test_bit(BTRFS_ROOT_REF_COWS, 4468 &root->state) && 4469 extent_start != 0) 4470 inode_sub_bytes(inode, num_dec); 4471 btrfs_mark_buffer_dirty(leaf); 4472 } else { 4473 extent_num_bytes = 4474 btrfs_file_extent_disk_num_bytes(leaf, 4475 fi); 4476 extent_offset = found_key.offset - 4477 btrfs_file_extent_offset(leaf, fi); 4478 4479 /* FIXME blocksize != 4096 */ 4480 num_dec = btrfs_file_extent_num_bytes(leaf, fi); 4481 if (extent_start != 0) { 4482 found_extent = 1; 4483 if (test_bit(BTRFS_ROOT_REF_COWS, 4484 &root->state)) 4485 inode_sub_bytes(inode, num_dec); 4486 } 4487 } 4488 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 4489 /* 4490 * we can't truncate inline items that have had 4491 * special encodings 4492 */ 4493 if (!del_item && 4494 btrfs_file_extent_encryption(leaf, fi) == 0 && 4495 btrfs_file_extent_other_encoding(leaf, fi) == 0) { 4496 4497 /* 4498 * Need to release path in order to truncate a 4499 * compressed extent. So delete any accumulated 4500 * extent items so far. 4501 */ 4502 if (btrfs_file_extent_compression(leaf, fi) != 4503 BTRFS_COMPRESS_NONE && pending_del_nr) { 4504 err = btrfs_del_items(trans, root, path, 4505 pending_del_slot, 4506 pending_del_nr); 4507 if (err) { 4508 btrfs_abort_transaction(trans, 4509 root, 4510 err); 4511 goto error; 4512 } 4513 pending_del_nr = 0; 4514 } 4515 4516 err = truncate_inline_extent(inode, path, 4517 &found_key, 4518 item_end, 4519 new_size); 4520 if (err) { 4521 btrfs_abort_transaction(trans, 4522 root, err); 4523 goto error; 4524 } 4525 } else if (test_bit(BTRFS_ROOT_REF_COWS, 4526 &root->state)) { 4527 inode_sub_bytes(inode, item_end + 1 - new_size); 4528 } 4529 } 4530 delete: 4531 if (del_item) { 4532 if (!pending_del_nr) { 4533 /* no pending yet, add ourselves */ 4534 pending_del_slot = path->slots[0]; 4535 pending_del_nr = 1; 4536 } else if (pending_del_nr && 4537 path->slots[0] + 1 == pending_del_slot) { 4538 /* hop on the pending chunk */ 4539 pending_del_nr++; 4540 pending_del_slot = path->slots[0]; 4541 } else { 4542 BUG(); 4543 } 4544 } else { 4545 break; 4546 } 4547 should_throttle = 0; 4548 4549 if (found_extent && 4550 (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || 4551 root == root->fs_info->tree_root)) { 4552 btrfs_set_path_blocking(path); 4553 bytes_deleted += extent_num_bytes; 4554 ret = btrfs_free_extent(trans, root, extent_start, 4555 extent_num_bytes, 0, 4556 btrfs_header_owner(leaf), 4557 ino, extent_offset); 4558 BUG_ON(ret); 4559 if (btrfs_should_throttle_delayed_refs(trans, root)) 4560 btrfs_async_run_delayed_refs(root, 4561 trans->transid, 4562 trans->delayed_ref_updates * 2, 0); 4563 if (be_nice) { 4564 if (truncate_space_check(trans, root, 4565 extent_num_bytes)) { 4566 should_end = 1; 4567 } 4568 if (btrfs_should_throttle_delayed_refs(trans, 4569 root)) { 4570 should_throttle = 1; 4571 } 4572 } 4573 } 4574 4575 if (found_type == BTRFS_INODE_ITEM_KEY) 4576 break; 4577 4578 if (path->slots[0] == 0 || 4579 path->slots[0] != pending_del_slot || 4580 should_throttle || should_end) { 4581 if (pending_del_nr) { 4582 ret = btrfs_del_items(trans, root, path, 4583 pending_del_slot, 4584 pending_del_nr); 4585 if (ret) { 4586 btrfs_abort_transaction(trans, 4587 root, ret); 4588 goto error; 4589 } 4590 pending_del_nr = 0; 4591 } 4592 btrfs_release_path(path); 4593 if (should_throttle) { 4594 unsigned long updates = trans->delayed_ref_updates; 4595 if (updates) { 4596 trans->delayed_ref_updates = 0; 4597 ret = btrfs_run_delayed_refs(trans, root, updates * 2); 4598 if (ret && !err) 4599 err = ret; 4600 } 4601 } 4602 /* 4603 * if we failed to refill our space rsv, bail out 4604 * and let the transaction restart 4605 */ 4606 if (should_end) { 4607 err = -EAGAIN; 4608 goto error; 4609 } 4610 goto search_again; 4611 } else { 4612 path->slots[0]--; 4613 } 4614 } 4615 out: 4616 if (pending_del_nr) { 4617 ret = btrfs_del_items(trans, root, path, pending_del_slot, 4618 pending_del_nr); 4619 if (ret) 4620 btrfs_abort_transaction(trans, root, ret); 4621 } 4622 error: 4623 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) 4624 btrfs_ordered_update_i_size(inode, last_size, NULL); 4625 4626 btrfs_free_path(path); 4627 4628 if (be_nice && bytes_deleted > SZ_32M) { 4629 unsigned long updates = trans->delayed_ref_updates; 4630 if (updates) { 4631 trans->delayed_ref_updates = 0; 4632 ret = btrfs_run_delayed_refs(trans, root, updates * 2); 4633 if (ret && !err) 4634 err = ret; 4635 } 4636 } 4637 return err; 4638 } 4639 4640 /* 4641 * btrfs_truncate_block - read, zero a chunk and write a block 4642 * @inode - inode that we're zeroing 4643 * @from - the offset to start zeroing 4644 * @len - the length to zero, 0 to zero the entire range respective to the 4645 * offset 4646 * @front - zero up to the offset instead of from the offset on 4647 * 4648 * This will find the block for the "from" offset and cow the block and zero the 4649 * part we want to zero. This is used with truncate and hole punching. 4650 */ 4651 int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len, 4652 int front) 4653 { 4654 struct address_space *mapping = inode->i_mapping; 4655 struct btrfs_root *root = BTRFS_I(inode)->root; 4656 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 4657 struct btrfs_ordered_extent *ordered; 4658 struct extent_state *cached_state = NULL; 4659 char *kaddr; 4660 u32 blocksize = root->sectorsize; 4661 pgoff_t index = from >> PAGE_SHIFT; 4662 unsigned offset = from & (blocksize - 1); 4663 struct page *page; 4664 gfp_t mask = btrfs_alloc_write_mask(mapping); 4665 int ret = 0; 4666 u64 block_start; 4667 u64 block_end; 4668 4669 if ((offset & (blocksize - 1)) == 0 && 4670 (!len || ((len & (blocksize - 1)) == 0))) 4671 goto out; 4672 4673 ret = btrfs_delalloc_reserve_space(inode, 4674 round_down(from, blocksize), blocksize); 4675 if (ret) 4676 goto out; 4677 4678 again: 4679 page = find_or_create_page(mapping, index, mask); 4680 if (!page) { 4681 btrfs_delalloc_release_space(inode, 4682 round_down(from, blocksize), 4683 blocksize); 4684 ret = -ENOMEM; 4685 goto out; 4686 } 4687 4688 block_start = round_down(from, blocksize); 4689 block_end = block_start + blocksize - 1; 4690 4691 if (!PageUptodate(page)) { 4692 ret = btrfs_readpage(NULL, page); 4693 lock_page(page); 4694 if (page->mapping != mapping) { 4695 unlock_page(page); 4696 put_page(page); 4697 goto again; 4698 } 4699 if (!PageUptodate(page)) { 4700 ret = -EIO; 4701 goto out_unlock; 4702 } 4703 } 4704 wait_on_page_writeback(page); 4705 4706 lock_extent_bits(io_tree, block_start, block_end, &cached_state); 4707 set_page_extent_mapped(page); 4708 4709 ordered = btrfs_lookup_ordered_extent(inode, block_start); 4710 if (ordered) { 4711 unlock_extent_cached(io_tree, block_start, block_end, 4712 &cached_state, GFP_NOFS); 4713 unlock_page(page); 4714 put_page(page); 4715 btrfs_start_ordered_extent(inode, ordered, 1); 4716 btrfs_put_ordered_extent(ordered); 4717 goto again; 4718 } 4719 4720 clear_extent_bit(&BTRFS_I(inode)->io_tree, block_start, block_end, 4721 EXTENT_DIRTY | EXTENT_DELALLOC | 4722 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 4723 0, 0, &cached_state, GFP_NOFS); 4724 4725 ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 4726 &cached_state); 4727 if (ret) { 4728 unlock_extent_cached(io_tree, block_start, block_end, 4729 &cached_state, GFP_NOFS); 4730 goto out_unlock; 4731 } 4732 4733 if (offset != blocksize) { 4734 if (!len) 4735 len = blocksize - offset; 4736 kaddr = kmap(page); 4737 if (front) 4738 memset(kaddr + (block_start - page_offset(page)), 4739 0, offset); 4740 else 4741 memset(kaddr + (block_start - page_offset(page)) + offset, 4742 0, len); 4743 flush_dcache_page(page); 4744 kunmap(page); 4745 } 4746 ClearPageChecked(page); 4747 set_page_dirty(page); 4748 unlock_extent_cached(io_tree, block_start, block_end, &cached_state, 4749 GFP_NOFS); 4750 4751 out_unlock: 4752 if (ret) 4753 btrfs_delalloc_release_space(inode, block_start, 4754 blocksize); 4755 unlock_page(page); 4756 put_page(page); 4757 out: 4758 return ret; 4759 } 4760 4761 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode, 4762 u64 offset, u64 len) 4763 { 4764 struct btrfs_trans_handle *trans; 4765 int ret; 4766 4767 /* 4768 * Still need to make sure the inode looks like it's been updated so 4769 * that any holes get logged if we fsync. 4770 */ 4771 if (btrfs_fs_incompat(root->fs_info, NO_HOLES)) { 4772 BTRFS_I(inode)->last_trans = root->fs_info->generation; 4773 BTRFS_I(inode)->last_sub_trans = root->log_transid; 4774 BTRFS_I(inode)->last_log_commit = root->last_log_commit; 4775 return 0; 4776 } 4777 4778 /* 4779 * 1 - for the one we're dropping 4780 * 1 - for the one we're adding 4781 * 1 - for updating the inode. 4782 */ 4783 trans = btrfs_start_transaction(root, 3); 4784 if (IS_ERR(trans)) 4785 return PTR_ERR(trans); 4786 4787 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1); 4788 if (ret) { 4789 btrfs_abort_transaction(trans, root, ret); 4790 btrfs_end_transaction(trans, root); 4791 return ret; 4792 } 4793 4794 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset, 4795 0, 0, len, 0, len, 0, 0, 0); 4796 if (ret) 4797 btrfs_abort_transaction(trans, root, ret); 4798 else 4799 btrfs_update_inode(trans, root, inode); 4800 btrfs_end_transaction(trans, root); 4801 return ret; 4802 } 4803 4804 /* 4805 * This function puts in dummy file extents for the area we're creating a hole 4806 * for. So if we are truncating this file to a larger size we need to insert 4807 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for 4808 * the range between oldsize and size 4809 */ 4810 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size) 4811 { 4812 struct btrfs_root *root = BTRFS_I(inode)->root; 4813 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 4814 struct extent_map *em = NULL; 4815 struct extent_state *cached_state = NULL; 4816 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 4817 u64 hole_start = ALIGN(oldsize, root->sectorsize); 4818 u64 block_end = ALIGN(size, root->sectorsize); 4819 u64 last_byte; 4820 u64 cur_offset; 4821 u64 hole_size; 4822 int err = 0; 4823 4824 /* 4825 * If our size started in the middle of a block we need to zero out the 4826 * rest of the block before we expand the i_size, otherwise we could 4827 * expose stale data. 4828 */ 4829 err = btrfs_truncate_block(inode, oldsize, 0, 0); 4830 if (err) 4831 return err; 4832 4833 if (size <= hole_start) 4834 return 0; 4835 4836 while (1) { 4837 struct btrfs_ordered_extent *ordered; 4838 4839 lock_extent_bits(io_tree, hole_start, block_end - 1, 4840 &cached_state); 4841 ordered = btrfs_lookup_ordered_range(inode, hole_start, 4842 block_end - hole_start); 4843 if (!ordered) 4844 break; 4845 unlock_extent_cached(io_tree, hole_start, block_end - 1, 4846 &cached_state, GFP_NOFS); 4847 btrfs_start_ordered_extent(inode, ordered, 1); 4848 btrfs_put_ordered_extent(ordered); 4849 } 4850 4851 cur_offset = hole_start; 4852 while (1) { 4853 em = btrfs_get_extent(inode, NULL, 0, cur_offset, 4854 block_end - cur_offset, 0); 4855 if (IS_ERR(em)) { 4856 err = PTR_ERR(em); 4857 em = NULL; 4858 break; 4859 } 4860 last_byte = min(extent_map_end(em), block_end); 4861 last_byte = ALIGN(last_byte , root->sectorsize); 4862 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) { 4863 struct extent_map *hole_em; 4864 hole_size = last_byte - cur_offset; 4865 4866 err = maybe_insert_hole(root, inode, cur_offset, 4867 hole_size); 4868 if (err) 4869 break; 4870 btrfs_drop_extent_cache(inode, cur_offset, 4871 cur_offset + hole_size - 1, 0); 4872 hole_em = alloc_extent_map(); 4873 if (!hole_em) { 4874 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 4875 &BTRFS_I(inode)->runtime_flags); 4876 goto next; 4877 } 4878 hole_em->start = cur_offset; 4879 hole_em->len = hole_size; 4880 hole_em->orig_start = cur_offset; 4881 4882 hole_em->block_start = EXTENT_MAP_HOLE; 4883 hole_em->block_len = 0; 4884 hole_em->orig_block_len = 0; 4885 hole_em->ram_bytes = hole_size; 4886 hole_em->bdev = root->fs_info->fs_devices->latest_bdev; 4887 hole_em->compress_type = BTRFS_COMPRESS_NONE; 4888 hole_em->generation = root->fs_info->generation; 4889 4890 while (1) { 4891 write_lock(&em_tree->lock); 4892 err = add_extent_mapping(em_tree, hole_em, 1); 4893 write_unlock(&em_tree->lock); 4894 if (err != -EEXIST) 4895 break; 4896 btrfs_drop_extent_cache(inode, cur_offset, 4897 cur_offset + 4898 hole_size - 1, 0); 4899 } 4900 free_extent_map(hole_em); 4901 } 4902 next: 4903 free_extent_map(em); 4904 em = NULL; 4905 cur_offset = last_byte; 4906 if (cur_offset >= block_end) 4907 break; 4908 } 4909 free_extent_map(em); 4910 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state, 4911 GFP_NOFS); 4912 return err; 4913 } 4914 4915 static int btrfs_setsize(struct inode *inode, struct iattr *attr) 4916 { 4917 struct btrfs_root *root = BTRFS_I(inode)->root; 4918 struct btrfs_trans_handle *trans; 4919 loff_t oldsize = i_size_read(inode); 4920 loff_t newsize = attr->ia_size; 4921 int mask = attr->ia_valid; 4922 int ret; 4923 4924 /* 4925 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a 4926 * special case where we need to update the times despite not having 4927 * these flags set. For all other operations the VFS set these flags 4928 * explicitly if it wants a timestamp update. 4929 */ 4930 if (newsize != oldsize) { 4931 inode_inc_iversion(inode); 4932 if (!(mask & (ATTR_CTIME | ATTR_MTIME))) 4933 inode->i_ctime = inode->i_mtime = 4934 current_fs_time(inode->i_sb); 4935 } 4936 4937 if (newsize > oldsize) { 4938 /* 4939 * Don't do an expanding truncate while snapshoting is ongoing. 4940 * This is to ensure the snapshot captures a fully consistent 4941 * state of this file - if the snapshot captures this expanding 4942 * truncation, it must capture all writes that happened before 4943 * this truncation. 4944 */ 4945 btrfs_wait_for_snapshot_creation(root); 4946 ret = btrfs_cont_expand(inode, oldsize, newsize); 4947 if (ret) { 4948 btrfs_end_write_no_snapshoting(root); 4949 return ret; 4950 } 4951 4952 trans = btrfs_start_transaction(root, 1); 4953 if (IS_ERR(trans)) { 4954 btrfs_end_write_no_snapshoting(root); 4955 return PTR_ERR(trans); 4956 } 4957 4958 i_size_write(inode, newsize); 4959 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL); 4960 pagecache_isize_extended(inode, oldsize, newsize); 4961 ret = btrfs_update_inode(trans, root, inode); 4962 btrfs_end_write_no_snapshoting(root); 4963 btrfs_end_transaction(trans, root); 4964 } else { 4965 4966 /* 4967 * We're truncating a file that used to have good data down to 4968 * zero. Make sure it gets into the ordered flush list so that 4969 * any new writes get down to disk quickly. 4970 */ 4971 if (newsize == 0) 4972 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE, 4973 &BTRFS_I(inode)->runtime_flags); 4974 4975 /* 4976 * 1 for the orphan item we're going to add 4977 * 1 for the orphan item deletion. 4978 */ 4979 trans = btrfs_start_transaction(root, 2); 4980 if (IS_ERR(trans)) 4981 return PTR_ERR(trans); 4982 4983 /* 4984 * We need to do this in case we fail at _any_ point during the 4985 * actual truncate. Once we do the truncate_setsize we could 4986 * invalidate pages which forces any outstanding ordered io to 4987 * be instantly completed which will give us extents that need 4988 * to be truncated. If we fail to get an orphan inode down we 4989 * could have left over extents that were never meant to live, 4990 * so we need to guarantee from this point on that everything 4991 * will be consistent. 4992 */ 4993 ret = btrfs_orphan_add(trans, inode); 4994 btrfs_end_transaction(trans, root); 4995 if (ret) 4996 return ret; 4997 4998 /* we don't support swapfiles, so vmtruncate shouldn't fail */ 4999 truncate_setsize(inode, newsize); 5000 5001 /* Disable nonlocked read DIO to avoid the end less truncate */ 5002 btrfs_inode_block_unlocked_dio(inode); 5003 inode_dio_wait(inode); 5004 btrfs_inode_resume_unlocked_dio(inode); 5005 5006 ret = btrfs_truncate(inode); 5007 if (ret && inode->i_nlink) { 5008 int err; 5009 5010 /* 5011 * failed to truncate, disk_i_size is only adjusted down 5012 * as we remove extents, so it should represent the true 5013 * size of the inode, so reset the in memory size and 5014 * delete our orphan entry. 5015 */ 5016 trans = btrfs_join_transaction(root); 5017 if (IS_ERR(trans)) { 5018 btrfs_orphan_del(NULL, inode); 5019 return ret; 5020 } 5021 i_size_write(inode, BTRFS_I(inode)->disk_i_size); 5022 err = btrfs_orphan_del(trans, inode); 5023 if (err) 5024 btrfs_abort_transaction(trans, root, err); 5025 btrfs_end_transaction(trans, root); 5026 } 5027 } 5028 5029 return ret; 5030 } 5031 5032 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) 5033 { 5034 struct inode *inode = d_inode(dentry); 5035 struct btrfs_root *root = BTRFS_I(inode)->root; 5036 int err; 5037 5038 if (btrfs_root_readonly(root)) 5039 return -EROFS; 5040 5041 err = inode_change_ok(inode, attr); 5042 if (err) 5043 return err; 5044 5045 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { 5046 err = btrfs_setsize(inode, attr); 5047 if (err) 5048 return err; 5049 } 5050 5051 if (attr->ia_valid) { 5052 setattr_copy(inode, attr); 5053 inode_inc_iversion(inode); 5054 err = btrfs_dirty_inode(inode); 5055 5056 if (!err && attr->ia_valid & ATTR_MODE) 5057 err = posix_acl_chmod(inode, inode->i_mode); 5058 } 5059 5060 return err; 5061 } 5062 5063 /* 5064 * While truncating the inode pages during eviction, we get the VFS calling 5065 * btrfs_invalidatepage() against each page of the inode. This is slow because 5066 * the calls to btrfs_invalidatepage() result in a huge amount of calls to 5067 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting 5068 * extent_state structures over and over, wasting lots of time. 5069 * 5070 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all 5071 * those expensive operations on a per page basis and do only the ordered io 5072 * finishing, while we release here the extent_map and extent_state structures, 5073 * without the excessive merging and splitting. 5074 */ 5075 static void evict_inode_truncate_pages(struct inode *inode) 5076 { 5077 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 5078 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree; 5079 struct rb_node *node; 5080 5081 ASSERT(inode->i_state & I_FREEING); 5082 truncate_inode_pages_final(&inode->i_data); 5083 5084 write_lock(&map_tree->lock); 5085 while (!RB_EMPTY_ROOT(&map_tree->map)) { 5086 struct extent_map *em; 5087 5088 node = rb_first(&map_tree->map); 5089 em = rb_entry(node, struct extent_map, rb_node); 5090 clear_bit(EXTENT_FLAG_PINNED, &em->flags); 5091 clear_bit(EXTENT_FLAG_LOGGING, &em->flags); 5092 remove_extent_mapping(map_tree, em); 5093 free_extent_map(em); 5094 if (need_resched()) { 5095 write_unlock(&map_tree->lock); 5096 cond_resched(); 5097 write_lock(&map_tree->lock); 5098 } 5099 } 5100 write_unlock(&map_tree->lock); 5101 5102 /* 5103 * Keep looping until we have no more ranges in the io tree. 5104 * We can have ongoing bios started by readpages (called from readahead) 5105 * that have their endio callback (extent_io.c:end_bio_extent_readpage) 5106 * still in progress (unlocked the pages in the bio but did not yet 5107 * unlocked the ranges in the io tree). Therefore this means some 5108 * ranges can still be locked and eviction started because before 5109 * submitting those bios, which are executed by a separate task (work 5110 * queue kthread), inode references (inode->i_count) were not taken 5111 * (which would be dropped in the end io callback of each bio). 5112 * Therefore here we effectively end up waiting for those bios and 5113 * anyone else holding locked ranges without having bumped the inode's 5114 * reference count - if we don't do it, when they access the inode's 5115 * io_tree to unlock a range it may be too late, leading to an 5116 * use-after-free issue. 5117 */ 5118 spin_lock(&io_tree->lock); 5119 while (!RB_EMPTY_ROOT(&io_tree->state)) { 5120 struct extent_state *state; 5121 struct extent_state *cached_state = NULL; 5122 u64 start; 5123 u64 end; 5124 5125 node = rb_first(&io_tree->state); 5126 state = rb_entry(node, struct extent_state, rb_node); 5127 start = state->start; 5128 end = state->end; 5129 spin_unlock(&io_tree->lock); 5130 5131 lock_extent_bits(io_tree, start, end, &cached_state); 5132 5133 /* 5134 * If still has DELALLOC flag, the extent didn't reach disk, 5135 * and its reserved space won't be freed by delayed_ref. 5136 * So we need to free its reserved space here. 5137 * (Refer to comment in btrfs_invalidatepage, case 2) 5138 * 5139 * Note, end is the bytenr of last byte, so we need + 1 here. 5140 */ 5141 if (state->state & EXTENT_DELALLOC) 5142 btrfs_qgroup_free_data(inode, start, end - start + 1); 5143 5144 clear_extent_bit(io_tree, start, end, 5145 EXTENT_LOCKED | EXTENT_DIRTY | 5146 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | 5147 EXTENT_DEFRAG, 1, 1, 5148 &cached_state, GFP_NOFS); 5149 5150 cond_resched(); 5151 spin_lock(&io_tree->lock); 5152 } 5153 spin_unlock(&io_tree->lock); 5154 } 5155 5156 void btrfs_evict_inode(struct inode *inode) 5157 { 5158 struct btrfs_trans_handle *trans; 5159 struct btrfs_root *root = BTRFS_I(inode)->root; 5160 struct btrfs_block_rsv *rsv, *global_rsv; 5161 int steal_from_global = 0; 5162 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); 5163 int ret; 5164 5165 trace_btrfs_inode_evict(inode); 5166 5167 evict_inode_truncate_pages(inode); 5168 5169 if (inode->i_nlink && 5170 ((btrfs_root_refs(&root->root_item) != 0 && 5171 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) || 5172 btrfs_is_free_space_inode(inode))) 5173 goto no_delete; 5174 5175 if (is_bad_inode(inode)) { 5176 btrfs_orphan_del(NULL, inode); 5177 goto no_delete; 5178 } 5179 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */ 5180 if (!special_file(inode->i_mode)) 5181 btrfs_wait_ordered_range(inode, 0, (u64)-1); 5182 5183 btrfs_free_io_failure_record(inode, 0, (u64)-1); 5184 5185 if (root->fs_info->log_root_recovering) { 5186 BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 5187 &BTRFS_I(inode)->runtime_flags)); 5188 goto no_delete; 5189 } 5190 5191 if (inode->i_nlink > 0) { 5192 BUG_ON(btrfs_root_refs(&root->root_item) != 0 && 5193 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID); 5194 goto no_delete; 5195 } 5196 5197 ret = btrfs_commit_inode_delayed_inode(inode); 5198 if (ret) { 5199 btrfs_orphan_del(NULL, inode); 5200 goto no_delete; 5201 } 5202 5203 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP); 5204 if (!rsv) { 5205 btrfs_orphan_del(NULL, inode); 5206 goto no_delete; 5207 } 5208 rsv->size = min_size; 5209 rsv->failfast = 1; 5210 global_rsv = &root->fs_info->global_block_rsv; 5211 5212 btrfs_i_size_write(inode, 0); 5213 5214 /* 5215 * This is a bit simpler than btrfs_truncate since we've already 5216 * reserved our space for our orphan item in the unlink, so we just 5217 * need to reserve some slack space in case we add bytes and update 5218 * inode item when doing the truncate. 5219 */ 5220 while (1) { 5221 ret = btrfs_block_rsv_refill(root, rsv, min_size, 5222 BTRFS_RESERVE_FLUSH_LIMIT); 5223 5224 /* 5225 * Try and steal from the global reserve since we will 5226 * likely not use this space anyway, we want to try as 5227 * hard as possible to get this to work. 5228 */ 5229 if (ret) 5230 steal_from_global++; 5231 else 5232 steal_from_global = 0; 5233 ret = 0; 5234 5235 /* 5236 * steal_from_global == 0: we reserved stuff, hooray! 5237 * steal_from_global == 1: we didn't reserve stuff, boo! 5238 * steal_from_global == 2: we've committed, still not a lot of 5239 * room but maybe we'll have room in the global reserve this 5240 * time. 5241 * steal_from_global == 3: abandon all hope! 5242 */ 5243 if (steal_from_global > 2) { 5244 btrfs_warn(root->fs_info, 5245 "Could not get space for a delete, will truncate on mount %d", 5246 ret); 5247 btrfs_orphan_del(NULL, inode); 5248 btrfs_free_block_rsv(root, rsv); 5249 goto no_delete; 5250 } 5251 5252 trans = btrfs_join_transaction(root); 5253 if (IS_ERR(trans)) { 5254 btrfs_orphan_del(NULL, inode); 5255 btrfs_free_block_rsv(root, rsv); 5256 goto no_delete; 5257 } 5258 5259 /* 5260 * We can't just steal from the global reserve, we need to make 5261 * sure there is room to do it, if not we need to commit and try 5262 * again. 5263 */ 5264 if (steal_from_global) { 5265 if (!btrfs_check_space_for_delayed_refs(trans, root)) 5266 ret = btrfs_block_rsv_migrate(global_rsv, rsv, 5267 min_size); 5268 else 5269 ret = -ENOSPC; 5270 } 5271 5272 /* 5273 * Couldn't steal from the global reserve, we have too much 5274 * pending stuff built up, commit the transaction and try it 5275 * again. 5276 */ 5277 if (ret) { 5278 ret = btrfs_commit_transaction(trans, root); 5279 if (ret) { 5280 btrfs_orphan_del(NULL, inode); 5281 btrfs_free_block_rsv(root, rsv); 5282 goto no_delete; 5283 } 5284 continue; 5285 } else { 5286 steal_from_global = 0; 5287 } 5288 5289 trans->block_rsv = rsv; 5290 5291 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0); 5292 if (ret != -ENOSPC && ret != -EAGAIN) 5293 break; 5294 5295 trans->block_rsv = &root->fs_info->trans_block_rsv; 5296 btrfs_end_transaction(trans, root); 5297 trans = NULL; 5298 btrfs_btree_balance_dirty(root); 5299 } 5300 5301 btrfs_free_block_rsv(root, rsv); 5302 5303 /* 5304 * Errors here aren't a big deal, it just means we leave orphan items 5305 * in the tree. They will be cleaned up on the next mount. 5306 */ 5307 if (ret == 0) { 5308 trans->block_rsv = root->orphan_block_rsv; 5309 btrfs_orphan_del(trans, inode); 5310 } else { 5311 btrfs_orphan_del(NULL, inode); 5312 } 5313 5314 trans->block_rsv = &root->fs_info->trans_block_rsv; 5315 if (!(root == root->fs_info->tree_root || 5316 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)) 5317 btrfs_return_ino(root, btrfs_ino(inode)); 5318 5319 btrfs_end_transaction(trans, root); 5320 btrfs_btree_balance_dirty(root); 5321 no_delete: 5322 btrfs_remove_delayed_node(inode); 5323 clear_inode(inode); 5324 } 5325 5326 /* 5327 * this returns the key found in the dir entry in the location pointer. 5328 * If no dir entries were found, location->objectid is 0. 5329 */ 5330 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, 5331 struct btrfs_key *location) 5332 { 5333 const char *name = dentry->d_name.name; 5334 int namelen = dentry->d_name.len; 5335 struct btrfs_dir_item *di; 5336 struct btrfs_path *path; 5337 struct btrfs_root *root = BTRFS_I(dir)->root; 5338 int ret = 0; 5339 5340 path = btrfs_alloc_path(); 5341 if (!path) 5342 return -ENOMEM; 5343 5344 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name, 5345 namelen, 0); 5346 if (IS_ERR(di)) 5347 ret = PTR_ERR(di); 5348 5349 if (IS_ERR_OR_NULL(di)) 5350 goto out_err; 5351 5352 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); 5353 out: 5354 btrfs_free_path(path); 5355 return ret; 5356 out_err: 5357 location->objectid = 0; 5358 goto out; 5359 } 5360 5361 /* 5362 * when we hit a tree root in a directory, the btrfs part of the inode 5363 * needs to be changed to reflect the root directory of the tree root. This 5364 * is kind of like crossing a mount point. 5365 */ 5366 static int fixup_tree_root_location(struct btrfs_root *root, 5367 struct inode *dir, 5368 struct dentry *dentry, 5369 struct btrfs_key *location, 5370 struct btrfs_root **sub_root) 5371 { 5372 struct btrfs_path *path; 5373 struct btrfs_root *new_root; 5374 struct btrfs_root_ref *ref; 5375 struct extent_buffer *leaf; 5376 struct btrfs_key key; 5377 int ret; 5378 int err = 0; 5379 5380 path = btrfs_alloc_path(); 5381 if (!path) { 5382 err = -ENOMEM; 5383 goto out; 5384 } 5385 5386 err = -ENOENT; 5387 key.objectid = BTRFS_I(dir)->root->root_key.objectid; 5388 key.type = BTRFS_ROOT_REF_KEY; 5389 key.offset = location->objectid; 5390 5391 ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, path, 5392 0, 0); 5393 if (ret) { 5394 if (ret < 0) 5395 err = ret; 5396 goto out; 5397 } 5398 5399 leaf = path->nodes[0]; 5400 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); 5401 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) || 5402 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len) 5403 goto out; 5404 5405 ret = memcmp_extent_buffer(leaf, dentry->d_name.name, 5406 (unsigned long)(ref + 1), 5407 dentry->d_name.len); 5408 if (ret) 5409 goto out; 5410 5411 btrfs_release_path(path); 5412 5413 new_root = btrfs_read_fs_root_no_name(root->fs_info, location); 5414 if (IS_ERR(new_root)) { 5415 err = PTR_ERR(new_root); 5416 goto out; 5417 } 5418 5419 *sub_root = new_root; 5420 location->objectid = btrfs_root_dirid(&new_root->root_item); 5421 location->type = BTRFS_INODE_ITEM_KEY; 5422 location->offset = 0; 5423 err = 0; 5424 out: 5425 btrfs_free_path(path); 5426 return err; 5427 } 5428 5429 static void inode_tree_add(struct inode *inode) 5430 { 5431 struct btrfs_root *root = BTRFS_I(inode)->root; 5432 struct btrfs_inode *entry; 5433 struct rb_node **p; 5434 struct rb_node *parent; 5435 struct rb_node *new = &BTRFS_I(inode)->rb_node; 5436 u64 ino = btrfs_ino(inode); 5437 5438 if (inode_unhashed(inode)) 5439 return; 5440 parent = NULL; 5441 spin_lock(&root->inode_lock); 5442 p = &root->inode_tree.rb_node; 5443 while (*p) { 5444 parent = *p; 5445 entry = rb_entry(parent, struct btrfs_inode, rb_node); 5446 5447 if (ino < btrfs_ino(&entry->vfs_inode)) 5448 p = &parent->rb_left; 5449 else if (ino > btrfs_ino(&entry->vfs_inode)) 5450 p = &parent->rb_right; 5451 else { 5452 WARN_ON(!(entry->vfs_inode.i_state & 5453 (I_WILL_FREE | I_FREEING))); 5454 rb_replace_node(parent, new, &root->inode_tree); 5455 RB_CLEAR_NODE(parent); 5456 spin_unlock(&root->inode_lock); 5457 return; 5458 } 5459 } 5460 rb_link_node(new, parent, p); 5461 rb_insert_color(new, &root->inode_tree); 5462 spin_unlock(&root->inode_lock); 5463 } 5464 5465 static void inode_tree_del(struct inode *inode) 5466 { 5467 struct btrfs_root *root = BTRFS_I(inode)->root; 5468 int empty = 0; 5469 5470 spin_lock(&root->inode_lock); 5471 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { 5472 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); 5473 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); 5474 empty = RB_EMPTY_ROOT(&root->inode_tree); 5475 } 5476 spin_unlock(&root->inode_lock); 5477 5478 if (empty && btrfs_root_refs(&root->root_item) == 0) { 5479 synchronize_srcu(&root->fs_info->subvol_srcu); 5480 spin_lock(&root->inode_lock); 5481 empty = RB_EMPTY_ROOT(&root->inode_tree); 5482 spin_unlock(&root->inode_lock); 5483 if (empty) 5484 btrfs_add_dead_root(root); 5485 } 5486 } 5487 5488 void btrfs_invalidate_inodes(struct btrfs_root *root) 5489 { 5490 struct rb_node *node; 5491 struct rb_node *prev; 5492 struct btrfs_inode *entry; 5493 struct inode *inode; 5494 u64 objectid = 0; 5495 5496 if (!test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) 5497 WARN_ON(btrfs_root_refs(&root->root_item) != 0); 5498 5499 spin_lock(&root->inode_lock); 5500 again: 5501 node = root->inode_tree.rb_node; 5502 prev = NULL; 5503 while (node) { 5504 prev = node; 5505 entry = rb_entry(node, struct btrfs_inode, rb_node); 5506 5507 if (objectid < btrfs_ino(&entry->vfs_inode)) 5508 node = node->rb_left; 5509 else if (objectid > btrfs_ino(&entry->vfs_inode)) 5510 node = node->rb_right; 5511 else 5512 break; 5513 } 5514 if (!node) { 5515 while (prev) { 5516 entry = rb_entry(prev, struct btrfs_inode, rb_node); 5517 if (objectid <= btrfs_ino(&entry->vfs_inode)) { 5518 node = prev; 5519 break; 5520 } 5521 prev = rb_next(prev); 5522 } 5523 } 5524 while (node) { 5525 entry = rb_entry(node, struct btrfs_inode, rb_node); 5526 objectid = btrfs_ino(&entry->vfs_inode) + 1; 5527 inode = igrab(&entry->vfs_inode); 5528 if (inode) { 5529 spin_unlock(&root->inode_lock); 5530 if (atomic_read(&inode->i_count) > 1) 5531 d_prune_aliases(inode); 5532 /* 5533 * btrfs_drop_inode will have it removed from 5534 * the inode cache when its usage count 5535 * hits zero. 5536 */ 5537 iput(inode); 5538 cond_resched(); 5539 spin_lock(&root->inode_lock); 5540 goto again; 5541 } 5542 5543 if (cond_resched_lock(&root->inode_lock)) 5544 goto again; 5545 5546 node = rb_next(node); 5547 } 5548 spin_unlock(&root->inode_lock); 5549 } 5550 5551 static int btrfs_init_locked_inode(struct inode *inode, void *p) 5552 { 5553 struct btrfs_iget_args *args = p; 5554 inode->i_ino = args->location->objectid; 5555 memcpy(&BTRFS_I(inode)->location, args->location, 5556 sizeof(*args->location)); 5557 BTRFS_I(inode)->root = args->root; 5558 return 0; 5559 } 5560 5561 static int btrfs_find_actor(struct inode *inode, void *opaque) 5562 { 5563 struct btrfs_iget_args *args = opaque; 5564 return args->location->objectid == BTRFS_I(inode)->location.objectid && 5565 args->root == BTRFS_I(inode)->root; 5566 } 5567 5568 static struct inode *btrfs_iget_locked(struct super_block *s, 5569 struct btrfs_key *location, 5570 struct btrfs_root *root) 5571 { 5572 struct inode *inode; 5573 struct btrfs_iget_args args; 5574 unsigned long hashval = btrfs_inode_hash(location->objectid, root); 5575 5576 args.location = location; 5577 args.root = root; 5578 5579 inode = iget5_locked(s, hashval, btrfs_find_actor, 5580 btrfs_init_locked_inode, 5581 (void *)&args); 5582 return inode; 5583 } 5584 5585 /* Get an inode object given its location and corresponding root. 5586 * Returns in *is_new if the inode was read from disk 5587 */ 5588 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, 5589 struct btrfs_root *root, int *new) 5590 { 5591 struct inode *inode; 5592 5593 inode = btrfs_iget_locked(s, location, root); 5594 if (!inode) 5595 return ERR_PTR(-ENOMEM); 5596 5597 if (inode->i_state & I_NEW) { 5598 btrfs_read_locked_inode(inode); 5599 if (!is_bad_inode(inode)) { 5600 inode_tree_add(inode); 5601 unlock_new_inode(inode); 5602 if (new) 5603 *new = 1; 5604 } else { 5605 unlock_new_inode(inode); 5606 iput(inode); 5607 inode = ERR_PTR(-ESTALE); 5608 } 5609 } 5610 5611 return inode; 5612 } 5613 5614 static struct inode *new_simple_dir(struct super_block *s, 5615 struct btrfs_key *key, 5616 struct btrfs_root *root) 5617 { 5618 struct inode *inode = new_inode(s); 5619 5620 if (!inode) 5621 return ERR_PTR(-ENOMEM); 5622 5623 BTRFS_I(inode)->root = root; 5624 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key)); 5625 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags); 5626 5627 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID; 5628 inode->i_op = &btrfs_dir_ro_inode_operations; 5629 inode->i_fop = &simple_dir_operations; 5630 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; 5631 inode->i_mtime = current_fs_time(inode->i_sb); 5632 inode->i_atime = inode->i_mtime; 5633 inode->i_ctime = inode->i_mtime; 5634 BTRFS_I(inode)->i_otime = inode->i_mtime; 5635 5636 return inode; 5637 } 5638 5639 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) 5640 { 5641 struct inode *inode; 5642 struct btrfs_root *root = BTRFS_I(dir)->root; 5643 struct btrfs_root *sub_root = root; 5644 struct btrfs_key location; 5645 int index; 5646 int ret = 0; 5647 5648 if (dentry->d_name.len > BTRFS_NAME_LEN) 5649 return ERR_PTR(-ENAMETOOLONG); 5650 5651 ret = btrfs_inode_by_name(dir, dentry, &location); 5652 if (ret < 0) 5653 return ERR_PTR(ret); 5654 5655 if (location.objectid == 0) 5656 return ERR_PTR(-ENOENT); 5657 5658 if (location.type == BTRFS_INODE_ITEM_KEY) { 5659 inode = btrfs_iget(dir->i_sb, &location, root, NULL); 5660 return inode; 5661 } 5662 5663 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); 5664 5665 index = srcu_read_lock(&root->fs_info->subvol_srcu); 5666 ret = fixup_tree_root_location(root, dir, dentry, 5667 &location, &sub_root); 5668 if (ret < 0) { 5669 if (ret != -ENOENT) 5670 inode = ERR_PTR(ret); 5671 else 5672 inode = new_simple_dir(dir->i_sb, &location, sub_root); 5673 } else { 5674 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL); 5675 } 5676 srcu_read_unlock(&root->fs_info->subvol_srcu, index); 5677 5678 if (!IS_ERR(inode) && root != sub_root) { 5679 down_read(&root->fs_info->cleanup_work_sem); 5680 if (!(inode->i_sb->s_flags & MS_RDONLY)) 5681 ret = btrfs_orphan_cleanup(sub_root); 5682 up_read(&root->fs_info->cleanup_work_sem); 5683 if (ret) { 5684 iput(inode); 5685 inode = ERR_PTR(ret); 5686 } 5687 } 5688 5689 return inode; 5690 } 5691 5692 static int btrfs_dentry_delete(const struct dentry *dentry) 5693 { 5694 struct btrfs_root *root; 5695 struct inode *inode = d_inode(dentry); 5696 5697 if (!inode && !IS_ROOT(dentry)) 5698 inode = d_inode(dentry->d_parent); 5699 5700 if (inode) { 5701 root = BTRFS_I(inode)->root; 5702 if (btrfs_root_refs(&root->root_item) == 0) 5703 return 1; 5704 5705 if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) 5706 return 1; 5707 } 5708 return 0; 5709 } 5710 5711 static void btrfs_dentry_release(struct dentry *dentry) 5712 { 5713 kfree(dentry->d_fsdata); 5714 } 5715 5716 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, 5717 unsigned int flags) 5718 { 5719 struct inode *inode; 5720 5721 inode = btrfs_lookup_dentry(dir, dentry); 5722 if (IS_ERR(inode)) { 5723 if (PTR_ERR(inode) == -ENOENT) 5724 inode = NULL; 5725 else 5726 return ERR_CAST(inode); 5727 } 5728 5729 return d_splice_alias(inode, dentry); 5730 } 5731 5732 unsigned char btrfs_filetype_table[] = { 5733 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK 5734 }; 5735 5736 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx) 5737 { 5738 struct inode *inode = file_inode(file); 5739 struct btrfs_root *root = BTRFS_I(inode)->root; 5740 struct btrfs_item *item; 5741 struct btrfs_dir_item *di; 5742 struct btrfs_key key; 5743 struct btrfs_key found_key; 5744 struct btrfs_path *path; 5745 struct list_head ins_list; 5746 struct list_head del_list; 5747 int ret; 5748 struct extent_buffer *leaf; 5749 int slot; 5750 unsigned char d_type; 5751 int over = 0; 5752 u32 di_cur; 5753 u32 di_total; 5754 u32 di_len; 5755 int key_type = BTRFS_DIR_INDEX_KEY; 5756 char tmp_name[32]; 5757 char *name_ptr; 5758 int name_len; 5759 int is_curr = 0; /* ctx->pos points to the current index? */ 5760 bool emitted; 5761 bool put = false; 5762 5763 /* FIXME, use a real flag for deciding about the key type */ 5764 if (root->fs_info->tree_root == root) 5765 key_type = BTRFS_DIR_ITEM_KEY; 5766 5767 if (!dir_emit_dots(file, ctx)) 5768 return 0; 5769 5770 path = btrfs_alloc_path(); 5771 if (!path) 5772 return -ENOMEM; 5773 5774 path->reada = READA_FORWARD; 5775 5776 if (key_type == BTRFS_DIR_INDEX_KEY) { 5777 INIT_LIST_HEAD(&ins_list); 5778 INIT_LIST_HEAD(&del_list); 5779 put = btrfs_readdir_get_delayed_items(inode, &ins_list, 5780 &del_list); 5781 } 5782 5783 key.type = key_type; 5784 key.offset = ctx->pos; 5785 key.objectid = btrfs_ino(inode); 5786 5787 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5788 if (ret < 0) 5789 goto err; 5790 5791 emitted = false; 5792 while (1) { 5793 leaf = path->nodes[0]; 5794 slot = path->slots[0]; 5795 if (slot >= btrfs_header_nritems(leaf)) { 5796 ret = btrfs_next_leaf(root, path); 5797 if (ret < 0) 5798 goto err; 5799 else if (ret > 0) 5800 break; 5801 continue; 5802 } 5803 5804 item = btrfs_item_nr(slot); 5805 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5806 5807 if (found_key.objectid != key.objectid) 5808 break; 5809 if (found_key.type != key_type) 5810 break; 5811 if (found_key.offset < ctx->pos) 5812 goto next; 5813 if (key_type == BTRFS_DIR_INDEX_KEY && 5814 btrfs_should_delete_dir_index(&del_list, 5815 found_key.offset)) 5816 goto next; 5817 5818 ctx->pos = found_key.offset; 5819 is_curr = 1; 5820 5821 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); 5822 di_cur = 0; 5823 di_total = btrfs_item_size(leaf, item); 5824 5825 while (di_cur < di_total) { 5826 struct btrfs_key location; 5827 5828 if (verify_dir_item(root, leaf, di)) 5829 break; 5830 5831 name_len = btrfs_dir_name_len(leaf, di); 5832 if (name_len <= sizeof(tmp_name)) { 5833 name_ptr = tmp_name; 5834 } else { 5835 name_ptr = kmalloc(name_len, GFP_KERNEL); 5836 if (!name_ptr) { 5837 ret = -ENOMEM; 5838 goto err; 5839 } 5840 } 5841 read_extent_buffer(leaf, name_ptr, 5842 (unsigned long)(di + 1), name_len); 5843 5844 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)]; 5845 btrfs_dir_item_key_to_cpu(leaf, di, &location); 5846 5847 5848 /* is this a reference to our own snapshot? If so 5849 * skip it. 5850 * 5851 * In contrast to old kernels, we insert the snapshot's 5852 * dir item and dir index after it has been created, so 5853 * we won't find a reference to our own snapshot. We 5854 * still keep the following code for backward 5855 * compatibility. 5856 */ 5857 if (location.type == BTRFS_ROOT_ITEM_KEY && 5858 location.objectid == root->root_key.objectid) { 5859 over = 0; 5860 goto skip; 5861 } 5862 over = !dir_emit(ctx, name_ptr, name_len, 5863 location.objectid, d_type); 5864 5865 skip: 5866 if (name_ptr != tmp_name) 5867 kfree(name_ptr); 5868 5869 if (over) 5870 goto nopos; 5871 emitted = true; 5872 di_len = btrfs_dir_name_len(leaf, di) + 5873 btrfs_dir_data_len(leaf, di) + sizeof(*di); 5874 di_cur += di_len; 5875 di = (struct btrfs_dir_item *)((char *)di + di_len); 5876 } 5877 next: 5878 path->slots[0]++; 5879 } 5880 5881 if (key_type == BTRFS_DIR_INDEX_KEY) { 5882 if (is_curr) 5883 ctx->pos++; 5884 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list, &emitted); 5885 if (ret) 5886 goto nopos; 5887 } 5888 5889 /* 5890 * If we haven't emitted any dir entry, we must not touch ctx->pos as 5891 * it was was set to the termination value in previous call. We assume 5892 * that "." and ".." were emitted if we reach this point and set the 5893 * termination value as well for an empty directory. 5894 */ 5895 if (ctx->pos > 2 && !emitted) 5896 goto nopos; 5897 5898 /* Reached end of directory/root. Bump pos past the last item. */ 5899 ctx->pos++; 5900 5901 /* 5902 * Stop new entries from being returned after we return the last 5903 * entry. 5904 * 5905 * New directory entries are assigned a strictly increasing 5906 * offset. This means that new entries created during readdir 5907 * are *guaranteed* to be seen in the future by that readdir. 5908 * This has broken buggy programs which operate on names as 5909 * they're returned by readdir. Until we re-use freed offsets 5910 * we have this hack to stop new entries from being returned 5911 * under the assumption that they'll never reach this huge 5912 * offset. 5913 * 5914 * This is being careful not to overflow 32bit loff_t unless the 5915 * last entry requires it because doing so has broken 32bit apps 5916 * in the past. 5917 */ 5918 if (key_type == BTRFS_DIR_INDEX_KEY) { 5919 if (ctx->pos >= INT_MAX) 5920 ctx->pos = LLONG_MAX; 5921 else 5922 ctx->pos = INT_MAX; 5923 } 5924 nopos: 5925 ret = 0; 5926 err: 5927 if (put) 5928 btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list); 5929 btrfs_free_path(path); 5930 return ret; 5931 } 5932 5933 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc) 5934 { 5935 struct btrfs_root *root = BTRFS_I(inode)->root; 5936 struct btrfs_trans_handle *trans; 5937 int ret = 0; 5938 bool nolock = false; 5939 5940 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags)) 5941 return 0; 5942 5943 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(inode)) 5944 nolock = true; 5945 5946 if (wbc->sync_mode == WB_SYNC_ALL) { 5947 if (nolock) 5948 trans = btrfs_join_transaction_nolock(root); 5949 else 5950 trans = btrfs_join_transaction(root); 5951 if (IS_ERR(trans)) 5952 return PTR_ERR(trans); 5953 ret = btrfs_commit_transaction(trans, root); 5954 } 5955 return ret; 5956 } 5957 5958 /* 5959 * This is somewhat expensive, updating the tree every time the 5960 * inode changes. But, it is most likely to find the inode in cache. 5961 * FIXME, needs more benchmarking...there are no reasons other than performance 5962 * to keep or drop this code. 5963 */ 5964 static int btrfs_dirty_inode(struct inode *inode) 5965 { 5966 struct btrfs_root *root = BTRFS_I(inode)->root; 5967 struct btrfs_trans_handle *trans; 5968 int ret; 5969 5970 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags)) 5971 return 0; 5972 5973 trans = btrfs_join_transaction(root); 5974 if (IS_ERR(trans)) 5975 return PTR_ERR(trans); 5976 5977 ret = btrfs_update_inode(trans, root, inode); 5978 if (ret && ret == -ENOSPC) { 5979 /* whoops, lets try again with the full transaction */ 5980 btrfs_end_transaction(trans, root); 5981 trans = btrfs_start_transaction(root, 1); 5982 if (IS_ERR(trans)) 5983 return PTR_ERR(trans); 5984 5985 ret = btrfs_update_inode(trans, root, inode); 5986 } 5987 btrfs_end_transaction(trans, root); 5988 if (BTRFS_I(inode)->delayed_node) 5989 btrfs_balance_delayed_items(root); 5990 5991 return ret; 5992 } 5993 5994 /* 5995 * This is a copy of file_update_time. We need this so we can return error on 5996 * ENOSPC for updating the inode in the case of file write and mmap writes. 5997 */ 5998 static int btrfs_update_time(struct inode *inode, struct timespec *now, 5999 int flags) 6000 { 6001 struct btrfs_root *root = BTRFS_I(inode)->root; 6002 6003 if (btrfs_root_readonly(root)) 6004 return -EROFS; 6005 6006 if (flags & S_VERSION) 6007 inode_inc_iversion(inode); 6008 if (flags & S_CTIME) 6009 inode->i_ctime = *now; 6010 if (flags & S_MTIME) 6011 inode->i_mtime = *now; 6012 if (flags & S_ATIME) 6013 inode->i_atime = *now; 6014 return btrfs_dirty_inode(inode); 6015 } 6016 6017 /* 6018 * find the highest existing sequence number in a directory 6019 * and then set the in-memory index_cnt variable to reflect 6020 * free sequence numbers 6021 */ 6022 static int btrfs_set_inode_index_count(struct inode *inode) 6023 { 6024 struct btrfs_root *root = BTRFS_I(inode)->root; 6025 struct btrfs_key key, found_key; 6026 struct btrfs_path *path; 6027 struct extent_buffer *leaf; 6028 int ret; 6029 6030 key.objectid = btrfs_ino(inode); 6031 key.type = BTRFS_DIR_INDEX_KEY; 6032 key.offset = (u64)-1; 6033 6034 path = btrfs_alloc_path(); 6035 if (!path) 6036 return -ENOMEM; 6037 6038 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 6039 if (ret < 0) 6040 goto out; 6041 /* FIXME: we should be able to handle this */ 6042 if (ret == 0) 6043 goto out; 6044 ret = 0; 6045 6046 /* 6047 * MAGIC NUMBER EXPLANATION: 6048 * since we search a directory based on f_pos we have to start at 2 6049 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody 6050 * else has to start at 2 6051 */ 6052 if (path->slots[0] == 0) { 6053 BTRFS_I(inode)->index_cnt = 2; 6054 goto out; 6055 } 6056 6057 path->slots[0]--; 6058 6059 leaf = path->nodes[0]; 6060 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6061 6062 if (found_key.objectid != btrfs_ino(inode) || 6063 found_key.type != BTRFS_DIR_INDEX_KEY) { 6064 BTRFS_I(inode)->index_cnt = 2; 6065 goto out; 6066 } 6067 6068 BTRFS_I(inode)->index_cnt = found_key.offset + 1; 6069 out: 6070 btrfs_free_path(path); 6071 return ret; 6072 } 6073 6074 /* 6075 * helper to find a free sequence number in a given directory. This current 6076 * code is very simple, later versions will do smarter things in the btree 6077 */ 6078 int btrfs_set_inode_index(struct inode *dir, u64 *index) 6079 { 6080 int ret = 0; 6081 6082 if (BTRFS_I(dir)->index_cnt == (u64)-1) { 6083 ret = btrfs_inode_delayed_dir_index_count(dir); 6084 if (ret) { 6085 ret = btrfs_set_inode_index_count(dir); 6086 if (ret) 6087 return ret; 6088 } 6089 } 6090 6091 *index = BTRFS_I(dir)->index_cnt; 6092 BTRFS_I(dir)->index_cnt++; 6093 6094 return ret; 6095 } 6096 6097 static int btrfs_insert_inode_locked(struct inode *inode) 6098 { 6099 struct btrfs_iget_args args; 6100 args.location = &BTRFS_I(inode)->location; 6101 args.root = BTRFS_I(inode)->root; 6102 6103 return insert_inode_locked4(inode, 6104 btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root), 6105 btrfs_find_actor, &args); 6106 } 6107 6108 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, 6109 struct btrfs_root *root, 6110 struct inode *dir, 6111 const char *name, int name_len, 6112 u64 ref_objectid, u64 objectid, 6113 umode_t mode, u64 *index) 6114 { 6115 struct inode *inode; 6116 struct btrfs_inode_item *inode_item; 6117 struct btrfs_key *location; 6118 struct btrfs_path *path; 6119 struct btrfs_inode_ref *ref; 6120 struct btrfs_key key[2]; 6121 u32 sizes[2]; 6122 int nitems = name ? 2 : 1; 6123 unsigned long ptr; 6124 int ret; 6125 6126 path = btrfs_alloc_path(); 6127 if (!path) 6128 return ERR_PTR(-ENOMEM); 6129 6130 inode = new_inode(root->fs_info->sb); 6131 if (!inode) { 6132 btrfs_free_path(path); 6133 return ERR_PTR(-ENOMEM); 6134 } 6135 6136 /* 6137 * O_TMPFILE, set link count to 0, so that after this point, 6138 * we fill in an inode item with the correct link count. 6139 */ 6140 if (!name) 6141 set_nlink(inode, 0); 6142 6143 /* 6144 * we have to initialize this early, so we can reclaim the inode 6145 * number if we fail afterwards in this function. 6146 */ 6147 inode->i_ino = objectid; 6148 6149 if (dir && name) { 6150 trace_btrfs_inode_request(dir); 6151 6152 ret = btrfs_set_inode_index(dir, index); 6153 if (ret) { 6154 btrfs_free_path(path); 6155 iput(inode); 6156 return ERR_PTR(ret); 6157 } 6158 } else if (dir) { 6159 *index = 0; 6160 } 6161 /* 6162 * index_cnt is ignored for everything but a dir, 6163 * btrfs_get_inode_index_count has an explanation for the magic 6164 * number 6165 */ 6166 BTRFS_I(inode)->index_cnt = 2; 6167 BTRFS_I(inode)->dir_index = *index; 6168 BTRFS_I(inode)->root = root; 6169 BTRFS_I(inode)->generation = trans->transid; 6170 inode->i_generation = BTRFS_I(inode)->generation; 6171 6172 /* 6173 * We could have gotten an inode number from somebody who was fsynced 6174 * and then removed in this same transaction, so let's just set full 6175 * sync since it will be a full sync anyway and this will blow away the 6176 * old info in the log. 6177 */ 6178 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 6179 6180 key[0].objectid = objectid; 6181 key[0].type = BTRFS_INODE_ITEM_KEY; 6182 key[0].offset = 0; 6183 6184 sizes[0] = sizeof(struct btrfs_inode_item); 6185 6186 if (name) { 6187 /* 6188 * Start new inodes with an inode_ref. This is slightly more 6189 * efficient for small numbers of hard links since they will 6190 * be packed into one item. Extended refs will kick in if we 6191 * add more hard links than can fit in the ref item. 6192 */ 6193 key[1].objectid = objectid; 6194 key[1].type = BTRFS_INODE_REF_KEY; 6195 key[1].offset = ref_objectid; 6196 6197 sizes[1] = name_len + sizeof(*ref); 6198 } 6199 6200 location = &BTRFS_I(inode)->location; 6201 location->objectid = objectid; 6202 location->offset = 0; 6203 location->type = BTRFS_INODE_ITEM_KEY; 6204 6205 ret = btrfs_insert_inode_locked(inode); 6206 if (ret < 0) 6207 goto fail; 6208 6209 path->leave_spinning = 1; 6210 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems); 6211 if (ret != 0) 6212 goto fail_unlock; 6213 6214 inode_init_owner(inode, dir, mode); 6215 inode_set_bytes(inode, 0); 6216 6217 inode->i_mtime = current_fs_time(inode->i_sb); 6218 inode->i_atime = inode->i_mtime; 6219 inode->i_ctime = inode->i_mtime; 6220 BTRFS_I(inode)->i_otime = inode->i_mtime; 6221 6222 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0], 6223 struct btrfs_inode_item); 6224 memset_extent_buffer(path->nodes[0], 0, (unsigned long)inode_item, 6225 sizeof(*inode_item)); 6226 fill_inode_item(trans, path->nodes[0], inode_item, inode); 6227 6228 if (name) { 6229 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, 6230 struct btrfs_inode_ref); 6231 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len); 6232 btrfs_set_inode_ref_index(path->nodes[0], ref, *index); 6233 ptr = (unsigned long)(ref + 1); 6234 write_extent_buffer(path->nodes[0], name, ptr, name_len); 6235 } 6236 6237 btrfs_mark_buffer_dirty(path->nodes[0]); 6238 btrfs_free_path(path); 6239 6240 btrfs_inherit_iflags(inode, dir); 6241 6242 if (S_ISREG(mode)) { 6243 if (btrfs_test_opt(root, NODATASUM)) 6244 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; 6245 if (btrfs_test_opt(root, NODATACOW)) 6246 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW | 6247 BTRFS_INODE_NODATASUM; 6248 } 6249 6250 inode_tree_add(inode); 6251 6252 trace_btrfs_inode_new(inode); 6253 btrfs_set_inode_last_trans(trans, inode); 6254 6255 btrfs_update_root_times(trans, root); 6256 6257 ret = btrfs_inode_inherit_props(trans, inode, dir); 6258 if (ret) 6259 btrfs_err(root->fs_info, 6260 "error inheriting props for ino %llu (root %llu): %d", 6261 btrfs_ino(inode), root->root_key.objectid, ret); 6262 6263 return inode; 6264 6265 fail_unlock: 6266 unlock_new_inode(inode); 6267 fail: 6268 if (dir && name) 6269 BTRFS_I(dir)->index_cnt--; 6270 btrfs_free_path(path); 6271 iput(inode); 6272 return ERR_PTR(ret); 6273 } 6274 6275 static inline u8 btrfs_inode_type(struct inode *inode) 6276 { 6277 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT]; 6278 } 6279 6280 /* 6281 * utility function to add 'inode' into 'parent_inode' with 6282 * a give name and a given sequence number. 6283 * if 'add_backref' is true, also insert a backref from the 6284 * inode to the parent directory. 6285 */ 6286 int btrfs_add_link(struct btrfs_trans_handle *trans, 6287 struct inode *parent_inode, struct inode *inode, 6288 const char *name, int name_len, int add_backref, u64 index) 6289 { 6290 int ret = 0; 6291 struct btrfs_key key; 6292 struct btrfs_root *root = BTRFS_I(parent_inode)->root; 6293 u64 ino = btrfs_ino(inode); 6294 u64 parent_ino = btrfs_ino(parent_inode); 6295 6296 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6297 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key)); 6298 } else { 6299 key.objectid = ino; 6300 key.type = BTRFS_INODE_ITEM_KEY; 6301 key.offset = 0; 6302 } 6303 6304 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6305 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, 6306 key.objectid, root->root_key.objectid, 6307 parent_ino, index, name, name_len); 6308 } else if (add_backref) { 6309 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino, 6310 parent_ino, index); 6311 } 6312 6313 /* Nothing to clean up yet */ 6314 if (ret) 6315 return ret; 6316 6317 ret = btrfs_insert_dir_item(trans, root, name, name_len, 6318 parent_inode, &key, 6319 btrfs_inode_type(inode), index); 6320 if (ret == -EEXIST || ret == -EOVERFLOW) 6321 goto fail_dir_item; 6322 else if (ret) { 6323 btrfs_abort_transaction(trans, root, ret); 6324 return ret; 6325 } 6326 6327 btrfs_i_size_write(parent_inode, parent_inode->i_size + 6328 name_len * 2); 6329 inode_inc_iversion(parent_inode); 6330 parent_inode->i_mtime = parent_inode->i_ctime = 6331 current_fs_time(parent_inode->i_sb); 6332 ret = btrfs_update_inode(trans, root, parent_inode); 6333 if (ret) 6334 btrfs_abort_transaction(trans, root, ret); 6335 return ret; 6336 6337 fail_dir_item: 6338 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6339 u64 local_index; 6340 int err; 6341 err = btrfs_del_root_ref(trans, root->fs_info->tree_root, 6342 key.objectid, root->root_key.objectid, 6343 parent_ino, &local_index, name, name_len); 6344 6345 } else if (add_backref) { 6346 u64 local_index; 6347 int err; 6348 6349 err = btrfs_del_inode_ref(trans, root, name, name_len, 6350 ino, parent_ino, &local_index); 6351 } 6352 return ret; 6353 } 6354 6355 static int btrfs_add_nondir(struct btrfs_trans_handle *trans, 6356 struct inode *dir, struct dentry *dentry, 6357 struct inode *inode, int backref, u64 index) 6358 { 6359 int err = btrfs_add_link(trans, dir, inode, 6360 dentry->d_name.name, dentry->d_name.len, 6361 backref, index); 6362 if (err > 0) 6363 err = -EEXIST; 6364 return err; 6365 } 6366 6367 static int btrfs_mknod(struct inode *dir, struct dentry *dentry, 6368 umode_t mode, dev_t rdev) 6369 { 6370 struct btrfs_trans_handle *trans; 6371 struct btrfs_root *root = BTRFS_I(dir)->root; 6372 struct inode *inode = NULL; 6373 int err; 6374 int drop_inode = 0; 6375 u64 objectid; 6376 u64 index = 0; 6377 6378 /* 6379 * 2 for inode item and ref 6380 * 2 for dir items 6381 * 1 for xattr if selinux is on 6382 */ 6383 trans = btrfs_start_transaction(root, 5); 6384 if (IS_ERR(trans)) 6385 return PTR_ERR(trans); 6386 6387 err = btrfs_find_free_ino(root, &objectid); 6388 if (err) 6389 goto out_unlock; 6390 6391 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6392 dentry->d_name.len, btrfs_ino(dir), objectid, 6393 mode, &index); 6394 if (IS_ERR(inode)) { 6395 err = PTR_ERR(inode); 6396 goto out_unlock; 6397 } 6398 6399 /* 6400 * If the active LSM wants to access the inode during 6401 * d_instantiate it needs these. Smack checks to see 6402 * if the filesystem supports xattrs by looking at the 6403 * ops vector. 6404 */ 6405 inode->i_op = &btrfs_special_inode_operations; 6406 init_special_inode(inode, inode->i_mode, rdev); 6407 6408 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6409 if (err) 6410 goto out_unlock_inode; 6411 6412 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); 6413 if (err) { 6414 goto out_unlock_inode; 6415 } else { 6416 btrfs_update_inode(trans, root, inode); 6417 unlock_new_inode(inode); 6418 d_instantiate(dentry, inode); 6419 } 6420 6421 out_unlock: 6422 btrfs_end_transaction(trans, root); 6423 btrfs_balance_delayed_items(root); 6424 btrfs_btree_balance_dirty(root); 6425 if (drop_inode) { 6426 inode_dec_link_count(inode); 6427 iput(inode); 6428 } 6429 return err; 6430 6431 out_unlock_inode: 6432 drop_inode = 1; 6433 unlock_new_inode(inode); 6434 goto out_unlock; 6435 6436 } 6437 6438 static int btrfs_create(struct inode *dir, struct dentry *dentry, 6439 umode_t mode, bool excl) 6440 { 6441 struct btrfs_trans_handle *trans; 6442 struct btrfs_root *root = BTRFS_I(dir)->root; 6443 struct inode *inode = NULL; 6444 int drop_inode_on_err = 0; 6445 int err; 6446 u64 objectid; 6447 u64 index = 0; 6448 6449 /* 6450 * 2 for inode item and ref 6451 * 2 for dir items 6452 * 1 for xattr if selinux is on 6453 */ 6454 trans = btrfs_start_transaction(root, 5); 6455 if (IS_ERR(trans)) 6456 return PTR_ERR(trans); 6457 6458 err = btrfs_find_free_ino(root, &objectid); 6459 if (err) 6460 goto out_unlock; 6461 6462 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6463 dentry->d_name.len, btrfs_ino(dir), objectid, 6464 mode, &index); 6465 if (IS_ERR(inode)) { 6466 err = PTR_ERR(inode); 6467 goto out_unlock; 6468 } 6469 drop_inode_on_err = 1; 6470 /* 6471 * If the active LSM wants to access the inode during 6472 * d_instantiate it needs these. Smack checks to see 6473 * if the filesystem supports xattrs by looking at the 6474 * ops vector. 6475 */ 6476 inode->i_fop = &btrfs_file_operations; 6477 inode->i_op = &btrfs_file_inode_operations; 6478 inode->i_mapping->a_ops = &btrfs_aops; 6479 6480 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6481 if (err) 6482 goto out_unlock_inode; 6483 6484 err = btrfs_update_inode(trans, root, inode); 6485 if (err) 6486 goto out_unlock_inode; 6487 6488 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); 6489 if (err) 6490 goto out_unlock_inode; 6491 6492 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 6493 unlock_new_inode(inode); 6494 d_instantiate(dentry, inode); 6495 6496 out_unlock: 6497 btrfs_end_transaction(trans, root); 6498 if (err && drop_inode_on_err) { 6499 inode_dec_link_count(inode); 6500 iput(inode); 6501 } 6502 btrfs_balance_delayed_items(root); 6503 btrfs_btree_balance_dirty(root); 6504 return err; 6505 6506 out_unlock_inode: 6507 unlock_new_inode(inode); 6508 goto out_unlock; 6509 6510 } 6511 6512 static int btrfs_link(struct dentry *old_dentry, struct inode *dir, 6513 struct dentry *dentry) 6514 { 6515 struct btrfs_trans_handle *trans = NULL; 6516 struct btrfs_root *root = BTRFS_I(dir)->root; 6517 struct inode *inode = d_inode(old_dentry); 6518 u64 index; 6519 int err; 6520 int drop_inode = 0; 6521 6522 /* do not allow sys_link's with other subvols of the same device */ 6523 if (root->objectid != BTRFS_I(inode)->root->objectid) 6524 return -EXDEV; 6525 6526 if (inode->i_nlink >= BTRFS_LINK_MAX) 6527 return -EMLINK; 6528 6529 err = btrfs_set_inode_index(dir, &index); 6530 if (err) 6531 goto fail; 6532 6533 /* 6534 * 2 items for inode and inode ref 6535 * 2 items for dir items 6536 * 1 item for parent inode 6537 */ 6538 trans = btrfs_start_transaction(root, 5); 6539 if (IS_ERR(trans)) { 6540 err = PTR_ERR(trans); 6541 trans = NULL; 6542 goto fail; 6543 } 6544 6545 /* There are several dir indexes for this inode, clear the cache. */ 6546 BTRFS_I(inode)->dir_index = 0ULL; 6547 inc_nlink(inode); 6548 inode_inc_iversion(inode); 6549 inode->i_ctime = current_fs_time(inode->i_sb); 6550 ihold(inode); 6551 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags); 6552 6553 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index); 6554 6555 if (err) { 6556 drop_inode = 1; 6557 } else { 6558 struct dentry *parent = dentry->d_parent; 6559 err = btrfs_update_inode(trans, root, inode); 6560 if (err) 6561 goto fail; 6562 if (inode->i_nlink == 1) { 6563 /* 6564 * If new hard link count is 1, it's a file created 6565 * with open(2) O_TMPFILE flag. 6566 */ 6567 err = btrfs_orphan_del(trans, inode); 6568 if (err) 6569 goto fail; 6570 } 6571 d_instantiate(dentry, inode); 6572 btrfs_log_new_name(trans, inode, NULL, parent); 6573 } 6574 6575 btrfs_balance_delayed_items(root); 6576 fail: 6577 if (trans) 6578 btrfs_end_transaction(trans, root); 6579 if (drop_inode) { 6580 inode_dec_link_count(inode); 6581 iput(inode); 6582 } 6583 btrfs_btree_balance_dirty(root); 6584 return err; 6585 } 6586 6587 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 6588 { 6589 struct inode *inode = NULL; 6590 struct btrfs_trans_handle *trans; 6591 struct btrfs_root *root = BTRFS_I(dir)->root; 6592 int err = 0; 6593 int drop_on_err = 0; 6594 u64 objectid = 0; 6595 u64 index = 0; 6596 6597 /* 6598 * 2 items for inode and ref 6599 * 2 items for dir items 6600 * 1 for xattr if selinux is on 6601 */ 6602 trans = btrfs_start_transaction(root, 5); 6603 if (IS_ERR(trans)) 6604 return PTR_ERR(trans); 6605 6606 err = btrfs_find_free_ino(root, &objectid); 6607 if (err) 6608 goto out_fail; 6609 6610 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6611 dentry->d_name.len, btrfs_ino(dir), objectid, 6612 S_IFDIR | mode, &index); 6613 if (IS_ERR(inode)) { 6614 err = PTR_ERR(inode); 6615 goto out_fail; 6616 } 6617 6618 drop_on_err = 1; 6619 /* these must be set before we unlock the inode */ 6620 inode->i_op = &btrfs_dir_inode_operations; 6621 inode->i_fop = &btrfs_dir_file_operations; 6622 6623 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6624 if (err) 6625 goto out_fail_inode; 6626 6627 btrfs_i_size_write(inode, 0); 6628 err = btrfs_update_inode(trans, root, inode); 6629 if (err) 6630 goto out_fail_inode; 6631 6632 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name, 6633 dentry->d_name.len, 0, index); 6634 if (err) 6635 goto out_fail_inode; 6636 6637 d_instantiate(dentry, inode); 6638 /* 6639 * mkdir is special. We're unlocking after we call d_instantiate 6640 * to avoid a race with nfsd calling d_instantiate. 6641 */ 6642 unlock_new_inode(inode); 6643 drop_on_err = 0; 6644 6645 out_fail: 6646 btrfs_end_transaction(trans, root); 6647 if (drop_on_err) { 6648 inode_dec_link_count(inode); 6649 iput(inode); 6650 } 6651 btrfs_balance_delayed_items(root); 6652 btrfs_btree_balance_dirty(root); 6653 return err; 6654 6655 out_fail_inode: 6656 unlock_new_inode(inode); 6657 goto out_fail; 6658 } 6659 6660 /* Find next extent map of a given extent map, caller needs to ensure locks */ 6661 static struct extent_map *next_extent_map(struct extent_map *em) 6662 { 6663 struct rb_node *next; 6664 6665 next = rb_next(&em->rb_node); 6666 if (!next) 6667 return NULL; 6668 return container_of(next, struct extent_map, rb_node); 6669 } 6670 6671 static struct extent_map *prev_extent_map(struct extent_map *em) 6672 { 6673 struct rb_node *prev; 6674 6675 prev = rb_prev(&em->rb_node); 6676 if (!prev) 6677 return NULL; 6678 return container_of(prev, struct extent_map, rb_node); 6679 } 6680 6681 /* helper for btfs_get_extent. Given an existing extent in the tree, 6682 * the existing extent is the nearest extent to map_start, 6683 * and an extent that you want to insert, deal with overlap and insert 6684 * the best fitted new extent into the tree. 6685 */ 6686 static int merge_extent_mapping(struct extent_map_tree *em_tree, 6687 struct extent_map *existing, 6688 struct extent_map *em, 6689 u64 map_start) 6690 { 6691 struct extent_map *prev; 6692 struct extent_map *next; 6693 u64 start; 6694 u64 end; 6695 u64 start_diff; 6696 6697 BUG_ON(map_start < em->start || map_start >= extent_map_end(em)); 6698 6699 if (existing->start > map_start) { 6700 next = existing; 6701 prev = prev_extent_map(next); 6702 } else { 6703 prev = existing; 6704 next = next_extent_map(prev); 6705 } 6706 6707 start = prev ? extent_map_end(prev) : em->start; 6708 start = max_t(u64, start, em->start); 6709 end = next ? next->start : extent_map_end(em); 6710 end = min_t(u64, end, extent_map_end(em)); 6711 start_diff = start - em->start; 6712 em->start = start; 6713 em->len = end - start; 6714 if (em->block_start < EXTENT_MAP_LAST_BYTE && 6715 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { 6716 em->block_start += start_diff; 6717 em->block_len -= start_diff; 6718 } 6719 return add_extent_mapping(em_tree, em, 0); 6720 } 6721 6722 static noinline int uncompress_inline(struct btrfs_path *path, 6723 struct page *page, 6724 size_t pg_offset, u64 extent_offset, 6725 struct btrfs_file_extent_item *item) 6726 { 6727 int ret; 6728 struct extent_buffer *leaf = path->nodes[0]; 6729 char *tmp; 6730 size_t max_size; 6731 unsigned long inline_size; 6732 unsigned long ptr; 6733 int compress_type; 6734 6735 WARN_ON(pg_offset != 0); 6736 compress_type = btrfs_file_extent_compression(leaf, item); 6737 max_size = btrfs_file_extent_ram_bytes(leaf, item); 6738 inline_size = btrfs_file_extent_inline_item_len(leaf, 6739 btrfs_item_nr(path->slots[0])); 6740 tmp = kmalloc(inline_size, GFP_NOFS); 6741 if (!tmp) 6742 return -ENOMEM; 6743 ptr = btrfs_file_extent_inline_start(item); 6744 6745 read_extent_buffer(leaf, tmp, ptr, inline_size); 6746 6747 max_size = min_t(unsigned long, PAGE_SIZE, max_size); 6748 ret = btrfs_decompress(compress_type, tmp, page, 6749 extent_offset, inline_size, max_size); 6750 kfree(tmp); 6751 return ret; 6752 } 6753 6754 /* 6755 * a bit scary, this does extent mapping from logical file offset to the disk. 6756 * the ugly parts come from merging extents from the disk with the in-ram 6757 * representation. This gets more complex because of the data=ordered code, 6758 * where the in-ram extents might be locked pending data=ordered completion. 6759 * 6760 * This also copies inline extents directly into the page. 6761 */ 6762 6763 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, 6764 size_t pg_offset, u64 start, u64 len, 6765 int create) 6766 { 6767 int ret; 6768 int err = 0; 6769 u64 extent_start = 0; 6770 u64 extent_end = 0; 6771 u64 objectid = btrfs_ino(inode); 6772 u32 found_type; 6773 struct btrfs_path *path = NULL; 6774 struct btrfs_root *root = BTRFS_I(inode)->root; 6775 struct btrfs_file_extent_item *item; 6776 struct extent_buffer *leaf; 6777 struct btrfs_key found_key; 6778 struct extent_map *em = NULL; 6779 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 6780 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 6781 struct btrfs_trans_handle *trans = NULL; 6782 const bool new_inline = !page || create; 6783 6784 again: 6785 read_lock(&em_tree->lock); 6786 em = lookup_extent_mapping(em_tree, start, len); 6787 if (em) 6788 em->bdev = root->fs_info->fs_devices->latest_bdev; 6789 read_unlock(&em_tree->lock); 6790 6791 if (em) { 6792 if (em->start > start || em->start + em->len <= start) 6793 free_extent_map(em); 6794 else if (em->block_start == EXTENT_MAP_INLINE && page) 6795 free_extent_map(em); 6796 else 6797 goto out; 6798 } 6799 em = alloc_extent_map(); 6800 if (!em) { 6801 err = -ENOMEM; 6802 goto out; 6803 } 6804 em->bdev = root->fs_info->fs_devices->latest_bdev; 6805 em->start = EXTENT_MAP_HOLE; 6806 em->orig_start = EXTENT_MAP_HOLE; 6807 em->len = (u64)-1; 6808 em->block_len = (u64)-1; 6809 6810 if (!path) { 6811 path = btrfs_alloc_path(); 6812 if (!path) { 6813 err = -ENOMEM; 6814 goto out; 6815 } 6816 /* 6817 * Chances are we'll be called again, so go ahead and do 6818 * readahead 6819 */ 6820 path->reada = READA_FORWARD; 6821 } 6822 6823 ret = btrfs_lookup_file_extent(trans, root, path, 6824 objectid, start, trans != NULL); 6825 if (ret < 0) { 6826 err = ret; 6827 goto out; 6828 } 6829 6830 if (ret != 0) { 6831 if (path->slots[0] == 0) 6832 goto not_found; 6833 path->slots[0]--; 6834 } 6835 6836 leaf = path->nodes[0]; 6837 item = btrfs_item_ptr(leaf, path->slots[0], 6838 struct btrfs_file_extent_item); 6839 /* are we inside the extent that was found? */ 6840 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6841 found_type = found_key.type; 6842 if (found_key.objectid != objectid || 6843 found_type != BTRFS_EXTENT_DATA_KEY) { 6844 /* 6845 * If we backup past the first extent we want to move forward 6846 * and see if there is an extent in front of us, otherwise we'll 6847 * say there is a hole for our whole search range which can 6848 * cause problems. 6849 */ 6850 extent_end = start; 6851 goto next; 6852 } 6853 6854 found_type = btrfs_file_extent_type(leaf, item); 6855 extent_start = found_key.offset; 6856 if (found_type == BTRFS_FILE_EXTENT_REG || 6857 found_type == BTRFS_FILE_EXTENT_PREALLOC) { 6858 extent_end = extent_start + 6859 btrfs_file_extent_num_bytes(leaf, item); 6860 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { 6861 size_t size; 6862 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item); 6863 extent_end = ALIGN(extent_start + size, root->sectorsize); 6864 } 6865 next: 6866 if (start >= extent_end) { 6867 path->slots[0]++; 6868 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 6869 ret = btrfs_next_leaf(root, path); 6870 if (ret < 0) { 6871 err = ret; 6872 goto out; 6873 } 6874 if (ret > 0) 6875 goto not_found; 6876 leaf = path->nodes[0]; 6877 } 6878 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6879 if (found_key.objectid != objectid || 6880 found_key.type != BTRFS_EXTENT_DATA_KEY) 6881 goto not_found; 6882 if (start + len <= found_key.offset) 6883 goto not_found; 6884 if (start > found_key.offset) 6885 goto next; 6886 em->start = start; 6887 em->orig_start = start; 6888 em->len = found_key.offset - start; 6889 goto not_found_em; 6890 } 6891 6892 btrfs_extent_item_to_extent_map(inode, path, item, new_inline, em); 6893 6894 if (found_type == BTRFS_FILE_EXTENT_REG || 6895 found_type == BTRFS_FILE_EXTENT_PREALLOC) { 6896 goto insert; 6897 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { 6898 unsigned long ptr; 6899 char *map; 6900 size_t size; 6901 size_t extent_offset; 6902 size_t copy_size; 6903 6904 if (new_inline) 6905 goto out; 6906 6907 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item); 6908 extent_offset = page_offset(page) + pg_offset - extent_start; 6909 copy_size = min_t(u64, PAGE_SIZE - pg_offset, 6910 size - extent_offset); 6911 em->start = extent_start + extent_offset; 6912 em->len = ALIGN(copy_size, root->sectorsize); 6913 em->orig_block_len = em->len; 6914 em->orig_start = em->start; 6915 ptr = btrfs_file_extent_inline_start(item) + extent_offset; 6916 if (create == 0 && !PageUptodate(page)) { 6917 if (btrfs_file_extent_compression(leaf, item) != 6918 BTRFS_COMPRESS_NONE) { 6919 ret = uncompress_inline(path, page, pg_offset, 6920 extent_offset, item); 6921 if (ret) { 6922 err = ret; 6923 goto out; 6924 } 6925 } else { 6926 map = kmap(page); 6927 read_extent_buffer(leaf, map + pg_offset, ptr, 6928 copy_size); 6929 if (pg_offset + copy_size < PAGE_SIZE) { 6930 memset(map + pg_offset + copy_size, 0, 6931 PAGE_SIZE - pg_offset - 6932 copy_size); 6933 } 6934 kunmap(page); 6935 } 6936 flush_dcache_page(page); 6937 } else if (create && PageUptodate(page)) { 6938 BUG(); 6939 if (!trans) { 6940 kunmap(page); 6941 free_extent_map(em); 6942 em = NULL; 6943 6944 btrfs_release_path(path); 6945 trans = btrfs_join_transaction(root); 6946 6947 if (IS_ERR(trans)) 6948 return ERR_CAST(trans); 6949 goto again; 6950 } 6951 map = kmap(page); 6952 write_extent_buffer(leaf, map + pg_offset, ptr, 6953 copy_size); 6954 kunmap(page); 6955 btrfs_mark_buffer_dirty(leaf); 6956 } 6957 set_extent_uptodate(io_tree, em->start, 6958 extent_map_end(em) - 1, NULL, GFP_NOFS); 6959 goto insert; 6960 } 6961 not_found: 6962 em->start = start; 6963 em->orig_start = start; 6964 em->len = len; 6965 not_found_em: 6966 em->block_start = EXTENT_MAP_HOLE; 6967 set_bit(EXTENT_FLAG_VACANCY, &em->flags); 6968 insert: 6969 btrfs_release_path(path); 6970 if (em->start > start || extent_map_end(em) <= start) { 6971 btrfs_err(root->fs_info, "bad extent! em: [%llu %llu] passed [%llu %llu]", 6972 em->start, em->len, start, len); 6973 err = -EIO; 6974 goto out; 6975 } 6976 6977 err = 0; 6978 write_lock(&em_tree->lock); 6979 ret = add_extent_mapping(em_tree, em, 0); 6980 /* it is possible that someone inserted the extent into the tree 6981 * while we had the lock dropped. It is also possible that 6982 * an overlapping map exists in the tree 6983 */ 6984 if (ret == -EEXIST) { 6985 struct extent_map *existing; 6986 6987 ret = 0; 6988 6989 existing = search_extent_mapping(em_tree, start, len); 6990 /* 6991 * existing will always be non-NULL, since there must be 6992 * extent causing the -EEXIST. 6993 */ 6994 if (existing->start == em->start && 6995 extent_map_end(existing) == extent_map_end(em) && 6996 em->block_start == existing->block_start) { 6997 /* 6998 * these two extents are the same, it happens 6999 * with inlines especially 7000 */ 7001 free_extent_map(em); 7002 em = existing; 7003 err = 0; 7004 7005 } else if (start >= extent_map_end(existing) || 7006 start <= existing->start) { 7007 /* 7008 * The existing extent map is the one nearest to 7009 * the [start, start + len) range which overlaps 7010 */ 7011 err = merge_extent_mapping(em_tree, existing, 7012 em, start); 7013 free_extent_map(existing); 7014 if (err) { 7015 free_extent_map(em); 7016 em = NULL; 7017 } 7018 } else { 7019 free_extent_map(em); 7020 em = existing; 7021 err = 0; 7022 } 7023 } 7024 write_unlock(&em_tree->lock); 7025 out: 7026 7027 trace_btrfs_get_extent(root, em); 7028 7029 btrfs_free_path(path); 7030 if (trans) { 7031 ret = btrfs_end_transaction(trans, root); 7032 if (!err) 7033 err = ret; 7034 } 7035 if (err) { 7036 free_extent_map(em); 7037 return ERR_PTR(err); 7038 } 7039 BUG_ON(!em); /* Error is always set */ 7040 return em; 7041 } 7042 7043 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page, 7044 size_t pg_offset, u64 start, u64 len, 7045 int create) 7046 { 7047 struct extent_map *em; 7048 struct extent_map *hole_em = NULL; 7049 u64 range_start = start; 7050 u64 end; 7051 u64 found; 7052 u64 found_end; 7053 int err = 0; 7054 7055 em = btrfs_get_extent(inode, page, pg_offset, start, len, create); 7056 if (IS_ERR(em)) 7057 return em; 7058 if (em) { 7059 /* 7060 * if our em maps to 7061 * - a hole or 7062 * - a pre-alloc extent, 7063 * there might actually be delalloc bytes behind it. 7064 */ 7065 if (em->block_start != EXTENT_MAP_HOLE && 7066 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7067 return em; 7068 else 7069 hole_em = em; 7070 } 7071 7072 /* check to see if we've wrapped (len == -1 or similar) */ 7073 end = start + len; 7074 if (end < start) 7075 end = (u64)-1; 7076 else 7077 end -= 1; 7078 7079 em = NULL; 7080 7081 /* ok, we didn't find anything, lets look for delalloc */ 7082 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start, 7083 end, len, EXTENT_DELALLOC, 1); 7084 found_end = range_start + found; 7085 if (found_end < range_start) 7086 found_end = (u64)-1; 7087 7088 /* 7089 * we didn't find anything useful, return 7090 * the original results from get_extent() 7091 */ 7092 if (range_start > end || found_end <= start) { 7093 em = hole_em; 7094 hole_em = NULL; 7095 goto out; 7096 } 7097 7098 /* adjust the range_start to make sure it doesn't 7099 * go backwards from the start they passed in 7100 */ 7101 range_start = max(start, range_start); 7102 found = found_end - range_start; 7103 7104 if (found > 0) { 7105 u64 hole_start = start; 7106 u64 hole_len = len; 7107 7108 em = alloc_extent_map(); 7109 if (!em) { 7110 err = -ENOMEM; 7111 goto out; 7112 } 7113 /* 7114 * when btrfs_get_extent can't find anything it 7115 * returns one huge hole 7116 * 7117 * make sure what it found really fits our range, and 7118 * adjust to make sure it is based on the start from 7119 * the caller 7120 */ 7121 if (hole_em) { 7122 u64 calc_end = extent_map_end(hole_em); 7123 7124 if (calc_end <= start || (hole_em->start > end)) { 7125 free_extent_map(hole_em); 7126 hole_em = NULL; 7127 } else { 7128 hole_start = max(hole_em->start, start); 7129 hole_len = calc_end - hole_start; 7130 } 7131 } 7132 em->bdev = NULL; 7133 if (hole_em && range_start > hole_start) { 7134 /* our hole starts before our delalloc, so we 7135 * have to return just the parts of the hole 7136 * that go until the delalloc starts 7137 */ 7138 em->len = min(hole_len, 7139 range_start - hole_start); 7140 em->start = hole_start; 7141 em->orig_start = hole_start; 7142 /* 7143 * don't adjust block start at all, 7144 * it is fixed at EXTENT_MAP_HOLE 7145 */ 7146 em->block_start = hole_em->block_start; 7147 em->block_len = hole_len; 7148 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags)) 7149 set_bit(EXTENT_FLAG_PREALLOC, &em->flags); 7150 } else { 7151 em->start = range_start; 7152 em->len = found; 7153 em->orig_start = range_start; 7154 em->block_start = EXTENT_MAP_DELALLOC; 7155 em->block_len = found; 7156 } 7157 } else if (hole_em) { 7158 return hole_em; 7159 } 7160 out: 7161 7162 free_extent_map(hole_em); 7163 if (err) { 7164 free_extent_map(em); 7165 return ERR_PTR(err); 7166 } 7167 return em; 7168 } 7169 7170 static struct extent_map *btrfs_create_dio_extent(struct inode *inode, 7171 const u64 start, 7172 const u64 len, 7173 const u64 orig_start, 7174 const u64 block_start, 7175 const u64 block_len, 7176 const u64 orig_block_len, 7177 const u64 ram_bytes, 7178 const int type) 7179 { 7180 struct extent_map *em = NULL; 7181 int ret; 7182 7183 down_read(&BTRFS_I(inode)->dio_sem); 7184 if (type != BTRFS_ORDERED_NOCOW) { 7185 em = create_pinned_em(inode, start, len, orig_start, 7186 block_start, block_len, orig_block_len, 7187 ram_bytes, type); 7188 if (IS_ERR(em)) 7189 goto out; 7190 } 7191 ret = btrfs_add_ordered_extent_dio(inode, start, block_start, 7192 len, block_len, type); 7193 if (ret) { 7194 if (em) { 7195 free_extent_map(em); 7196 btrfs_drop_extent_cache(inode, start, 7197 start + len - 1, 0); 7198 } 7199 em = ERR_PTR(ret); 7200 } 7201 out: 7202 up_read(&BTRFS_I(inode)->dio_sem); 7203 7204 return em; 7205 } 7206 7207 static struct extent_map *btrfs_new_extent_direct(struct inode *inode, 7208 u64 start, u64 len) 7209 { 7210 struct btrfs_root *root = BTRFS_I(inode)->root; 7211 struct extent_map *em; 7212 struct btrfs_key ins; 7213 u64 alloc_hint; 7214 int ret; 7215 7216 alloc_hint = get_extent_allocation_hint(inode, start, len); 7217 ret = btrfs_reserve_extent(root, len, root->sectorsize, 0, 7218 alloc_hint, &ins, 1, 1); 7219 if (ret) 7220 return ERR_PTR(ret); 7221 7222 em = btrfs_create_dio_extent(inode, start, ins.offset, start, 7223 ins.objectid, ins.offset, ins.offset, 7224 ins.offset, 0); 7225 btrfs_dec_block_group_reservations(root->fs_info, ins.objectid); 7226 if (IS_ERR(em)) 7227 btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1); 7228 7229 return em; 7230 } 7231 7232 /* 7233 * returns 1 when the nocow is safe, < 1 on error, 0 if the 7234 * block must be cow'd 7235 */ 7236 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len, 7237 u64 *orig_start, u64 *orig_block_len, 7238 u64 *ram_bytes) 7239 { 7240 struct btrfs_trans_handle *trans; 7241 struct btrfs_path *path; 7242 int ret; 7243 struct extent_buffer *leaf; 7244 struct btrfs_root *root = BTRFS_I(inode)->root; 7245 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 7246 struct btrfs_file_extent_item *fi; 7247 struct btrfs_key key; 7248 u64 disk_bytenr; 7249 u64 backref_offset; 7250 u64 extent_end; 7251 u64 num_bytes; 7252 int slot; 7253 int found_type; 7254 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW); 7255 7256 path = btrfs_alloc_path(); 7257 if (!path) 7258 return -ENOMEM; 7259 7260 ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(inode), 7261 offset, 0); 7262 if (ret < 0) 7263 goto out; 7264 7265 slot = path->slots[0]; 7266 if (ret == 1) { 7267 if (slot == 0) { 7268 /* can't find the item, must cow */ 7269 ret = 0; 7270 goto out; 7271 } 7272 slot--; 7273 } 7274 ret = 0; 7275 leaf = path->nodes[0]; 7276 btrfs_item_key_to_cpu(leaf, &key, slot); 7277 if (key.objectid != btrfs_ino(inode) || 7278 key.type != BTRFS_EXTENT_DATA_KEY) { 7279 /* not our file or wrong item type, must cow */ 7280 goto out; 7281 } 7282 7283 if (key.offset > offset) { 7284 /* Wrong offset, must cow */ 7285 goto out; 7286 } 7287 7288 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); 7289 found_type = btrfs_file_extent_type(leaf, fi); 7290 if (found_type != BTRFS_FILE_EXTENT_REG && 7291 found_type != BTRFS_FILE_EXTENT_PREALLOC) { 7292 /* not a regular extent, must cow */ 7293 goto out; 7294 } 7295 7296 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG) 7297 goto out; 7298 7299 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); 7300 if (extent_end <= offset) 7301 goto out; 7302 7303 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 7304 if (disk_bytenr == 0) 7305 goto out; 7306 7307 if (btrfs_file_extent_compression(leaf, fi) || 7308 btrfs_file_extent_encryption(leaf, fi) || 7309 btrfs_file_extent_other_encoding(leaf, fi)) 7310 goto out; 7311 7312 backref_offset = btrfs_file_extent_offset(leaf, fi); 7313 7314 if (orig_start) { 7315 *orig_start = key.offset - backref_offset; 7316 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi); 7317 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); 7318 } 7319 7320 if (btrfs_extent_readonly(root, disk_bytenr)) 7321 goto out; 7322 7323 num_bytes = min(offset + *len, extent_end) - offset; 7324 if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) { 7325 u64 range_end; 7326 7327 range_end = round_up(offset + num_bytes, root->sectorsize) - 1; 7328 ret = test_range_bit(io_tree, offset, range_end, 7329 EXTENT_DELALLOC, 0, NULL); 7330 if (ret) { 7331 ret = -EAGAIN; 7332 goto out; 7333 } 7334 } 7335 7336 btrfs_release_path(path); 7337 7338 /* 7339 * look for other files referencing this extent, if we 7340 * find any we must cow 7341 */ 7342 trans = btrfs_join_transaction(root); 7343 if (IS_ERR(trans)) { 7344 ret = 0; 7345 goto out; 7346 } 7347 7348 ret = btrfs_cross_ref_exist(trans, root, btrfs_ino(inode), 7349 key.offset - backref_offset, disk_bytenr); 7350 btrfs_end_transaction(trans, root); 7351 if (ret) { 7352 ret = 0; 7353 goto out; 7354 } 7355 7356 /* 7357 * adjust disk_bytenr and num_bytes to cover just the bytes 7358 * in this extent we are about to write. If there 7359 * are any csums in that range we have to cow in order 7360 * to keep the csums correct 7361 */ 7362 disk_bytenr += backref_offset; 7363 disk_bytenr += offset - key.offset; 7364 if (csum_exist_in_range(root, disk_bytenr, num_bytes)) 7365 goto out; 7366 /* 7367 * all of the above have passed, it is safe to overwrite this extent 7368 * without cow 7369 */ 7370 *len = num_bytes; 7371 ret = 1; 7372 out: 7373 btrfs_free_path(path); 7374 return ret; 7375 } 7376 7377 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end) 7378 { 7379 struct radix_tree_root *root = &inode->i_mapping->page_tree; 7380 int found = false; 7381 void **pagep = NULL; 7382 struct page *page = NULL; 7383 int start_idx; 7384 int end_idx; 7385 7386 start_idx = start >> PAGE_SHIFT; 7387 7388 /* 7389 * end is the last byte in the last page. end == start is legal 7390 */ 7391 end_idx = end >> PAGE_SHIFT; 7392 7393 rcu_read_lock(); 7394 7395 /* Most of the code in this while loop is lifted from 7396 * find_get_page. It's been modified to begin searching from a 7397 * page and return just the first page found in that range. If the 7398 * found idx is less than or equal to the end idx then we know that 7399 * a page exists. If no pages are found or if those pages are 7400 * outside of the range then we're fine (yay!) */ 7401 while (page == NULL && 7402 radix_tree_gang_lookup_slot(root, &pagep, NULL, start_idx, 1)) { 7403 page = radix_tree_deref_slot(pagep); 7404 if (unlikely(!page)) 7405 break; 7406 7407 if (radix_tree_exception(page)) { 7408 if (radix_tree_deref_retry(page)) { 7409 page = NULL; 7410 continue; 7411 } 7412 /* 7413 * Otherwise, shmem/tmpfs must be storing a swap entry 7414 * here as an exceptional entry: so return it without 7415 * attempting to raise page count. 7416 */ 7417 page = NULL; 7418 break; /* TODO: Is this relevant for this use case? */ 7419 } 7420 7421 if (!page_cache_get_speculative(page)) { 7422 page = NULL; 7423 continue; 7424 } 7425 7426 /* 7427 * Has the page moved? 7428 * This is part of the lockless pagecache protocol. See 7429 * include/linux/pagemap.h for details. 7430 */ 7431 if (unlikely(page != *pagep)) { 7432 put_page(page); 7433 page = NULL; 7434 } 7435 } 7436 7437 if (page) { 7438 if (page->index <= end_idx) 7439 found = true; 7440 put_page(page); 7441 } 7442 7443 rcu_read_unlock(); 7444 return found; 7445 } 7446 7447 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, 7448 struct extent_state **cached_state, int writing) 7449 { 7450 struct btrfs_ordered_extent *ordered; 7451 int ret = 0; 7452 7453 while (1) { 7454 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7455 cached_state); 7456 /* 7457 * We're concerned with the entire range that we're going to be 7458 * doing DIO to, so we need to make sure there's no ordered 7459 * extents in this range. 7460 */ 7461 ordered = btrfs_lookup_ordered_range(inode, lockstart, 7462 lockend - lockstart + 1); 7463 7464 /* 7465 * We need to make sure there are no buffered pages in this 7466 * range either, we could have raced between the invalidate in 7467 * generic_file_direct_write and locking the extent. The 7468 * invalidate needs to happen so that reads after a write do not 7469 * get stale data. 7470 */ 7471 if (!ordered && 7472 (!writing || 7473 !btrfs_page_exists_in_range(inode, lockstart, lockend))) 7474 break; 7475 7476 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7477 cached_state, GFP_NOFS); 7478 7479 if (ordered) { 7480 /* 7481 * If we are doing a DIO read and the ordered extent we 7482 * found is for a buffered write, we can not wait for it 7483 * to complete and retry, because if we do so we can 7484 * deadlock with concurrent buffered writes on page 7485 * locks. This happens only if our DIO read covers more 7486 * than one extent map, if at this point has already 7487 * created an ordered extent for a previous extent map 7488 * and locked its range in the inode's io tree, and a 7489 * concurrent write against that previous extent map's 7490 * range and this range started (we unlock the ranges 7491 * in the io tree only when the bios complete and 7492 * buffered writes always lock pages before attempting 7493 * to lock range in the io tree). 7494 */ 7495 if (writing || 7496 test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) 7497 btrfs_start_ordered_extent(inode, ordered, 1); 7498 else 7499 ret = -ENOTBLK; 7500 btrfs_put_ordered_extent(ordered); 7501 } else { 7502 /* 7503 * We could trigger writeback for this range (and wait 7504 * for it to complete) and then invalidate the pages for 7505 * this range (through invalidate_inode_pages2_range()), 7506 * but that can lead us to a deadlock with a concurrent 7507 * call to readpages() (a buffered read or a defrag call 7508 * triggered a readahead) on a page lock due to an 7509 * ordered dio extent we created before but did not have 7510 * yet a corresponding bio submitted (whence it can not 7511 * complete), which makes readpages() wait for that 7512 * ordered extent to complete while holding a lock on 7513 * that page. 7514 */ 7515 ret = -ENOTBLK; 7516 } 7517 7518 if (ret) 7519 break; 7520 7521 cond_resched(); 7522 } 7523 7524 return ret; 7525 } 7526 7527 static struct extent_map *create_pinned_em(struct inode *inode, u64 start, 7528 u64 len, u64 orig_start, 7529 u64 block_start, u64 block_len, 7530 u64 orig_block_len, u64 ram_bytes, 7531 int type) 7532 { 7533 struct extent_map_tree *em_tree; 7534 struct extent_map *em; 7535 struct btrfs_root *root = BTRFS_I(inode)->root; 7536 int ret; 7537 7538 em_tree = &BTRFS_I(inode)->extent_tree; 7539 em = alloc_extent_map(); 7540 if (!em) 7541 return ERR_PTR(-ENOMEM); 7542 7543 em->start = start; 7544 em->orig_start = orig_start; 7545 em->mod_start = start; 7546 em->mod_len = len; 7547 em->len = len; 7548 em->block_len = block_len; 7549 em->block_start = block_start; 7550 em->bdev = root->fs_info->fs_devices->latest_bdev; 7551 em->orig_block_len = orig_block_len; 7552 em->ram_bytes = ram_bytes; 7553 em->generation = -1; 7554 set_bit(EXTENT_FLAG_PINNED, &em->flags); 7555 if (type == BTRFS_ORDERED_PREALLOC) 7556 set_bit(EXTENT_FLAG_FILLING, &em->flags); 7557 7558 do { 7559 btrfs_drop_extent_cache(inode, em->start, 7560 em->start + em->len - 1, 0); 7561 write_lock(&em_tree->lock); 7562 ret = add_extent_mapping(em_tree, em, 1); 7563 write_unlock(&em_tree->lock); 7564 } while (ret == -EEXIST); 7565 7566 if (ret) { 7567 free_extent_map(em); 7568 return ERR_PTR(ret); 7569 } 7570 7571 return em; 7572 } 7573 7574 static void adjust_dio_outstanding_extents(struct inode *inode, 7575 struct btrfs_dio_data *dio_data, 7576 const u64 len) 7577 { 7578 unsigned num_extents; 7579 7580 num_extents = (unsigned) div64_u64(len + BTRFS_MAX_EXTENT_SIZE - 1, 7581 BTRFS_MAX_EXTENT_SIZE); 7582 /* 7583 * If we have an outstanding_extents count still set then we're 7584 * within our reservation, otherwise we need to adjust our inode 7585 * counter appropriately. 7586 */ 7587 if (dio_data->outstanding_extents) { 7588 dio_data->outstanding_extents -= num_extents; 7589 } else { 7590 spin_lock(&BTRFS_I(inode)->lock); 7591 BTRFS_I(inode)->outstanding_extents += num_extents; 7592 spin_unlock(&BTRFS_I(inode)->lock); 7593 } 7594 } 7595 7596 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock, 7597 struct buffer_head *bh_result, int create) 7598 { 7599 struct extent_map *em; 7600 struct btrfs_root *root = BTRFS_I(inode)->root; 7601 struct extent_state *cached_state = NULL; 7602 struct btrfs_dio_data *dio_data = NULL; 7603 u64 start = iblock << inode->i_blkbits; 7604 u64 lockstart, lockend; 7605 u64 len = bh_result->b_size; 7606 int unlock_bits = EXTENT_LOCKED; 7607 int ret = 0; 7608 7609 if (create) 7610 unlock_bits |= EXTENT_DIRTY; 7611 else 7612 len = min_t(u64, len, root->sectorsize); 7613 7614 lockstart = start; 7615 lockend = start + len - 1; 7616 7617 if (current->journal_info) { 7618 /* 7619 * Need to pull our outstanding extents and set journal_info to NULL so 7620 * that anything that needs to check if there's a transaction doesn't get 7621 * confused. 7622 */ 7623 dio_data = current->journal_info; 7624 current->journal_info = NULL; 7625 } 7626 7627 /* 7628 * If this errors out it's because we couldn't invalidate pagecache for 7629 * this range and we need to fallback to buffered. 7630 */ 7631 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, 7632 create)) { 7633 ret = -ENOTBLK; 7634 goto err; 7635 } 7636 7637 em = btrfs_get_extent(inode, NULL, 0, start, len, 0); 7638 if (IS_ERR(em)) { 7639 ret = PTR_ERR(em); 7640 goto unlock_err; 7641 } 7642 7643 /* 7644 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered 7645 * io. INLINE is special, and we could probably kludge it in here, but 7646 * it's still buffered so for safety lets just fall back to the generic 7647 * buffered path. 7648 * 7649 * For COMPRESSED we _have_ to read the entire extent in so we can 7650 * decompress it, so there will be buffering required no matter what we 7651 * do, so go ahead and fallback to buffered. 7652 * 7653 * We return -ENOTBLK because that's what makes DIO go ahead and go back 7654 * to buffered IO. Don't blame me, this is the price we pay for using 7655 * the generic code. 7656 */ 7657 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) || 7658 em->block_start == EXTENT_MAP_INLINE) { 7659 free_extent_map(em); 7660 ret = -ENOTBLK; 7661 goto unlock_err; 7662 } 7663 7664 /* Just a good old fashioned hole, return */ 7665 if (!create && (em->block_start == EXTENT_MAP_HOLE || 7666 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) { 7667 free_extent_map(em); 7668 goto unlock_err; 7669 } 7670 7671 /* 7672 * We don't allocate a new extent in the following cases 7673 * 7674 * 1) The inode is marked as NODATACOW. In this case we'll just use the 7675 * existing extent. 7676 * 2) The extent is marked as PREALLOC. We're good to go here and can 7677 * just use the extent. 7678 * 7679 */ 7680 if (!create) { 7681 len = min(len, em->len - (start - em->start)); 7682 lockstart = start + len; 7683 goto unlock; 7684 } 7685 7686 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) || 7687 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && 7688 em->block_start != EXTENT_MAP_HOLE)) { 7689 int type; 7690 u64 block_start, orig_start, orig_block_len, ram_bytes; 7691 7692 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7693 type = BTRFS_ORDERED_PREALLOC; 7694 else 7695 type = BTRFS_ORDERED_NOCOW; 7696 len = min(len, em->len - (start - em->start)); 7697 block_start = em->block_start + (start - em->start); 7698 7699 if (can_nocow_extent(inode, start, &len, &orig_start, 7700 &orig_block_len, &ram_bytes) == 1 && 7701 btrfs_inc_nocow_writers(root->fs_info, block_start)) { 7702 struct extent_map *em2; 7703 7704 em2 = btrfs_create_dio_extent(inode, start, len, 7705 orig_start, block_start, 7706 len, orig_block_len, 7707 ram_bytes, type); 7708 btrfs_dec_nocow_writers(root->fs_info, block_start); 7709 if (type == BTRFS_ORDERED_PREALLOC) { 7710 free_extent_map(em); 7711 em = em2; 7712 } 7713 if (em2 && IS_ERR(em2)) { 7714 ret = PTR_ERR(em2); 7715 goto unlock_err; 7716 } 7717 goto unlock; 7718 } 7719 } 7720 7721 /* 7722 * this will cow the extent, reset the len in case we changed 7723 * it above 7724 */ 7725 len = bh_result->b_size; 7726 free_extent_map(em); 7727 em = btrfs_new_extent_direct(inode, start, len); 7728 if (IS_ERR(em)) { 7729 ret = PTR_ERR(em); 7730 goto unlock_err; 7731 } 7732 len = min(len, em->len - (start - em->start)); 7733 unlock: 7734 bh_result->b_blocknr = (em->block_start + (start - em->start)) >> 7735 inode->i_blkbits; 7736 bh_result->b_size = len; 7737 bh_result->b_bdev = em->bdev; 7738 set_buffer_mapped(bh_result); 7739 if (create) { 7740 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7741 set_buffer_new(bh_result); 7742 7743 /* 7744 * Need to update the i_size under the extent lock so buffered 7745 * readers will get the updated i_size when we unlock. 7746 */ 7747 if (start + len > i_size_read(inode)) 7748 i_size_write(inode, start + len); 7749 7750 adjust_dio_outstanding_extents(inode, dio_data, len); 7751 btrfs_free_reserved_data_space(inode, start, len); 7752 WARN_ON(dio_data->reserve < len); 7753 dio_data->reserve -= len; 7754 dio_data->unsubmitted_oe_range_end = start + len; 7755 current->journal_info = dio_data; 7756 } 7757 7758 /* 7759 * In the case of write we need to clear and unlock the entire range, 7760 * in the case of read we need to unlock only the end area that we 7761 * aren't using if there is any left over space. 7762 */ 7763 if (lockstart < lockend) { 7764 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, 7765 lockend, unlock_bits, 1, 0, 7766 &cached_state, GFP_NOFS); 7767 } else { 7768 free_extent_state(cached_state); 7769 } 7770 7771 free_extent_map(em); 7772 7773 return 0; 7774 7775 unlock_err: 7776 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7777 unlock_bits, 1, 0, &cached_state, GFP_NOFS); 7778 err: 7779 if (dio_data) 7780 current->journal_info = dio_data; 7781 /* 7782 * Compensate the delalloc release we do in btrfs_direct_IO() when we 7783 * write less data then expected, so that we don't underflow our inode's 7784 * outstanding extents counter. 7785 */ 7786 if (create && dio_data) 7787 adjust_dio_outstanding_extents(inode, dio_data, len); 7788 7789 return ret; 7790 } 7791 7792 static inline int submit_dio_repair_bio(struct inode *inode, struct bio *bio, 7793 int rw, int mirror_num) 7794 { 7795 struct btrfs_root *root = BTRFS_I(inode)->root; 7796 int ret; 7797 7798 BUG_ON(rw & REQ_WRITE); 7799 7800 bio_get(bio); 7801 7802 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 7803 BTRFS_WQ_ENDIO_DIO_REPAIR); 7804 if (ret) 7805 goto err; 7806 7807 ret = btrfs_map_bio(root, rw, bio, mirror_num, 0); 7808 err: 7809 bio_put(bio); 7810 return ret; 7811 } 7812 7813 static int btrfs_check_dio_repairable(struct inode *inode, 7814 struct bio *failed_bio, 7815 struct io_failure_record *failrec, 7816 int failed_mirror) 7817 { 7818 int num_copies; 7819 7820 num_copies = btrfs_num_copies(BTRFS_I(inode)->root->fs_info, 7821 failrec->logical, failrec->len); 7822 if (num_copies == 1) { 7823 /* 7824 * we only have a single copy of the data, so don't bother with 7825 * all the retry and error correction code that follows. no 7826 * matter what the error is, it is very likely to persist. 7827 */ 7828 pr_debug("Check DIO Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d\n", 7829 num_copies, failrec->this_mirror, failed_mirror); 7830 return 0; 7831 } 7832 7833 failrec->failed_mirror = failed_mirror; 7834 failrec->this_mirror++; 7835 if (failrec->this_mirror == failed_mirror) 7836 failrec->this_mirror++; 7837 7838 if (failrec->this_mirror > num_copies) { 7839 pr_debug("Check DIO Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d\n", 7840 num_copies, failrec->this_mirror, failed_mirror); 7841 return 0; 7842 } 7843 7844 return 1; 7845 } 7846 7847 static int dio_read_error(struct inode *inode, struct bio *failed_bio, 7848 struct page *page, unsigned int pgoff, 7849 u64 start, u64 end, int failed_mirror, 7850 bio_end_io_t *repair_endio, void *repair_arg) 7851 { 7852 struct io_failure_record *failrec; 7853 struct bio *bio; 7854 int isector; 7855 int read_mode; 7856 int ret; 7857 7858 BUG_ON(failed_bio->bi_rw & REQ_WRITE); 7859 7860 ret = btrfs_get_io_failure_record(inode, start, end, &failrec); 7861 if (ret) 7862 return ret; 7863 7864 ret = btrfs_check_dio_repairable(inode, failed_bio, failrec, 7865 failed_mirror); 7866 if (!ret) { 7867 free_io_failure(inode, failrec); 7868 return -EIO; 7869 } 7870 7871 if ((failed_bio->bi_vcnt > 1) 7872 || (failed_bio->bi_io_vec->bv_len 7873 > BTRFS_I(inode)->root->sectorsize)) 7874 read_mode = READ_SYNC | REQ_FAILFAST_DEV; 7875 else 7876 read_mode = READ_SYNC; 7877 7878 isector = start - btrfs_io_bio(failed_bio)->logical; 7879 isector >>= inode->i_sb->s_blocksize_bits; 7880 bio = btrfs_create_repair_bio(inode, failed_bio, failrec, page, 7881 pgoff, isector, repair_endio, repair_arg); 7882 if (!bio) { 7883 free_io_failure(inode, failrec); 7884 return -EIO; 7885 } 7886 7887 btrfs_debug(BTRFS_I(inode)->root->fs_info, 7888 "Repair DIO Read Error: submitting new dio read[%#x] to this_mirror=%d, in_validation=%d\n", 7889 read_mode, failrec->this_mirror, failrec->in_validation); 7890 7891 ret = submit_dio_repair_bio(inode, bio, read_mode, 7892 failrec->this_mirror); 7893 if (ret) { 7894 free_io_failure(inode, failrec); 7895 bio_put(bio); 7896 } 7897 7898 return ret; 7899 } 7900 7901 struct btrfs_retry_complete { 7902 struct completion done; 7903 struct inode *inode; 7904 u64 start; 7905 int uptodate; 7906 }; 7907 7908 static void btrfs_retry_endio_nocsum(struct bio *bio) 7909 { 7910 struct btrfs_retry_complete *done = bio->bi_private; 7911 struct inode *inode; 7912 struct bio_vec *bvec; 7913 int i; 7914 7915 if (bio->bi_error) 7916 goto end; 7917 7918 ASSERT(bio->bi_vcnt == 1); 7919 inode = bio->bi_io_vec->bv_page->mapping->host; 7920 ASSERT(bio->bi_io_vec->bv_len == BTRFS_I(inode)->root->sectorsize); 7921 7922 done->uptodate = 1; 7923 bio_for_each_segment_all(bvec, bio, i) 7924 clean_io_failure(done->inode, done->start, bvec->bv_page, 0); 7925 end: 7926 complete(&done->done); 7927 bio_put(bio); 7928 } 7929 7930 static int __btrfs_correct_data_nocsum(struct inode *inode, 7931 struct btrfs_io_bio *io_bio) 7932 { 7933 struct btrfs_fs_info *fs_info; 7934 struct bio_vec *bvec; 7935 struct btrfs_retry_complete done; 7936 u64 start; 7937 unsigned int pgoff; 7938 u32 sectorsize; 7939 int nr_sectors; 7940 int i; 7941 int ret; 7942 7943 fs_info = BTRFS_I(inode)->root->fs_info; 7944 sectorsize = BTRFS_I(inode)->root->sectorsize; 7945 7946 start = io_bio->logical; 7947 done.inode = inode; 7948 7949 bio_for_each_segment_all(bvec, &io_bio->bio, i) { 7950 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec->bv_len); 7951 pgoff = bvec->bv_offset; 7952 7953 next_block_or_try_again: 7954 done.uptodate = 0; 7955 done.start = start; 7956 init_completion(&done.done); 7957 7958 ret = dio_read_error(inode, &io_bio->bio, bvec->bv_page, 7959 pgoff, start, start + sectorsize - 1, 7960 io_bio->mirror_num, 7961 btrfs_retry_endio_nocsum, &done); 7962 if (ret) 7963 return ret; 7964 7965 wait_for_completion(&done.done); 7966 7967 if (!done.uptodate) { 7968 /* We might have another mirror, so try again */ 7969 goto next_block_or_try_again; 7970 } 7971 7972 start += sectorsize; 7973 7974 if (nr_sectors--) { 7975 pgoff += sectorsize; 7976 goto next_block_or_try_again; 7977 } 7978 } 7979 7980 return 0; 7981 } 7982 7983 static void btrfs_retry_endio(struct bio *bio) 7984 { 7985 struct btrfs_retry_complete *done = bio->bi_private; 7986 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 7987 struct inode *inode; 7988 struct bio_vec *bvec; 7989 u64 start; 7990 int uptodate; 7991 int ret; 7992 int i; 7993 7994 if (bio->bi_error) 7995 goto end; 7996 7997 uptodate = 1; 7998 7999 start = done->start; 8000 8001 ASSERT(bio->bi_vcnt == 1); 8002 inode = bio->bi_io_vec->bv_page->mapping->host; 8003 ASSERT(bio->bi_io_vec->bv_len == BTRFS_I(inode)->root->sectorsize); 8004 8005 bio_for_each_segment_all(bvec, bio, i) { 8006 ret = __readpage_endio_check(done->inode, io_bio, i, 8007 bvec->bv_page, bvec->bv_offset, 8008 done->start, bvec->bv_len); 8009 if (!ret) 8010 clean_io_failure(done->inode, done->start, 8011 bvec->bv_page, bvec->bv_offset); 8012 else 8013 uptodate = 0; 8014 } 8015 8016 done->uptodate = uptodate; 8017 end: 8018 complete(&done->done); 8019 bio_put(bio); 8020 } 8021 8022 static int __btrfs_subio_endio_read(struct inode *inode, 8023 struct btrfs_io_bio *io_bio, int err) 8024 { 8025 struct btrfs_fs_info *fs_info; 8026 struct bio_vec *bvec; 8027 struct btrfs_retry_complete done; 8028 u64 start; 8029 u64 offset = 0; 8030 u32 sectorsize; 8031 int nr_sectors; 8032 unsigned int pgoff; 8033 int csum_pos; 8034 int i; 8035 int ret; 8036 8037 fs_info = BTRFS_I(inode)->root->fs_info; 8038 sectorsize = BTRFS_I(inode)->root->sectorsize; 8039 8040 err = 0; 8041 start = io_bio->logical; 8042 done.inode = inode; 8043 8044 bio_for_each_segment_all(bvec, &io_bio->bio, i) { 8045 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec->bv_len); 8046 8047 pgoff = bvec->bv_offset; 8048 next_block: 8049 csum_pos = BTRFS_BYTES_TO_BLKS(fs_info, offset); 8050 ret = __readpage_endio_check(inode, io_bio, csum_pos, 8051 bvec->bv_page, pgoff, start, 8052 sectorsize); 8053 if (likely(!ret)) 8054 goto next; 8055 try_again: 8056 done.uptodate = 0; 8057 done.start = start; 8058 init_completion(&done.done); 8059 8060 ret = dio_read_error(inode, &io_bio->bio, bvec->bv_page, 8061 pgoff, start, start + sectorsize - 1, 8062 io_bio->mirror_num, 8063 btrfs_retry_endio, &done); 8064 if (ret) { 8065 err = ret; 8066 goto next; 8067 } 8068 8069 wait_for_completion(&done.done); 8070 8071 if (!done.uptodate) { 8072 /* We might have another mirror, so try again */ 8073 goto try_again; 8074 } 8075 next: 8076 offset += sectorsize; 8077 start += sectorsize; 8078 8079 ASSERT(nr_sectors); 8080 8081 if (--nr_sectors) { 8082 pgoff += sectorsize; 8083 goto next_block; 8084 } 8085 } 8086 8087 return err; 8088 } 8089 8090 static int btrfs_subio_endio_read(struct inode *inode, 8091 struct btrfs_io_bio *io_bio, int err) 8092 { 8093 bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 8094 8095 if (skip_csum) { 8096 if (unlikely(err)) 8097 return __btrfs_correct_data_nocsum(inode, io_bio); 8098 else 8099 return 0; 8100 } else { 8101 return __btrfs_subio_endio_read(inode, io_bio, err); 8102 } 8103 } 8104 8105 static void btrfs_endio_direct_read(struct bio *bio) 8106 { 8107 struct btrfs_dio_private *dip = bio->bi_private; 8108 struct inode *inode = dip->inode; 8109 struct bio *dio_bio; 8110 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 8111 int err = bio->bi_error; 8112 8113 if (dip->flags & BTRFS_DIO_ORIG_BIO_SUBMITTED) 8114 err = btrfs_subio_endio_read(inode, io_bio, err); 8115 8116 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset, 8117 dip->logical_offset + dip->bytes - 1); 8118 dio_bio = dip->dio_bio; 8119 8120 kfree(dip); 8121 8122 dio_bio->bi_error = bio->bi_error; 8123 dio_end_io(dio_bio, bio->bi_error); 8124 8125 if (io_bio->end_io) 8126 io_bio->end_io(io_bio, err); 8127 bio_put(bio); 8128 } 8129 8130 static void btrfs_endio_direct_write_update_ordered(struct inode *inode, 8131 const u64 offset, 8132 const u64 bytes, 8133 const int uptodate) 8134 { 8135 struct btrfs_root *root = BTRFS_I(inode)->root; 8136 struct btrfs_ordered_extent *ordered = NULL; 8137 u64 ordered_offset = offset; 8138 u64 ordered_bytes = bytes; 8139 int ret; 8140 8141 again: 8142 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered, 8143 &ordered_offset, 8144 ordered_bytes, 8145 uptodate); 8146 if (!ret) 8147 goto out_test; 8148 8149 btrfs_init_work(&ordered->work, btrfs_endio_write_helper, 8150 finish_ordered_fn, NULL, NULL); 8151 btrfs_queue_work(root->fs_info->endio_write_workers, 8152 &ordered->work); 8153 out_test: 8154 /* 8155 * our bio might span multiple ordered extents. If we haven't 8156 * completed the accounting for the whole dio, go back and try again 8157 */ 8158 if (ordered_offset < offset + bytes) { 8159 ordered_bytes = offset + bytes - ordered_offset; 8160 ordered = NULL; 8161 goto again; 8162 } 8163 } 8164 8165 static void btrfs_endio_direct_write(struct bio *bio) 8166 { 8167 struct btrfs_dio_private *dip = bio->bi_private; 8168 struct bio *dio_bio = dip->dio_bio; 8169 8170 btrfs_endio_direct_write_update_ordered(dip->inode, 8171 dip->logical_offset, 8172 dip->bytes, 8173 !bio->bi_error); 8174 8175 kfree(dip); 8176 8177 dio_bio->bi_error = bio->bi_error; 8178 dio_end_io(dio_bio, bio->bi_error); 8179 bio_put(bio); 8180 } 8181 8182 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw, 8183 struct bio *bio, int mirror_num, 8184 unsigned long bio_flags, u64 offset) 8185 { 8186 int ret; 8187 struct btrfs_root *root = BTRFS_I(inode)->root; 8188 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1); 8189 BUG_ON(ret); /* -ENOMEM */ 8190 return 0; 8191 } 8192 8193 static void btrfs_end_dio_bio(struct bio *bio) 8194 { 8195 struct btrfs_dio_private *dip = bio->bi_private; 8196 int err = bio->bi_error; 8197 8198 if (err) 8199 btrfs_warn(BTRFS_I(dip->inode)->root->fs_info, 8200 "direct IO failed ino %llu rw %lu sector %#Lx len %u err no %d", 8201 btrfs_ino(dip->inode), bio->bi_rw, 8202 (unsigned long long)bio->bi_iter.bi_sector, 8203 bio->bi_iter.bi_size, err); 8204 8205 if (dip->subio_endio) 8206 err = dip->subio_endio(dip->inode, btrfs_io_bio(bio), err); 8207 8208 if (err) { 8209 dip->errors = 1; 8210 8211 /* 8212 * before atomic variable goto zero, we must make sure 8213 * dip->errors is perceived to be set. 8214 */ 8215 smp_mb__before_atomic(); 8216 } 8217 8218 /* if there are more bios still pending for this dio, just exit */ 8219 if (!atomic_dec_and_test(&dip->pending_bios)) 8220 goto out; 8221 8222 if (dip->errors) { 8223 bio_io_error(dip->orig_bio); 8224 } else { 8225 dip->dio_bio->bi_error = 0; 8226 bio_endio(dip->orig_bio); 8227 } 8228 out: 8229 bio_put(bio); 8230 } 8231 8232 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev, 8233 u64 first_sector, gfp_t gfp_flags) 8234 { 8235 struct bio *bio; 8236 bio = btrfs_bio_alloc(bdev, first_sector, BIO_MAX_PAGES, gfp_flags); 8237 if (bio) 8238 bio_associate_current(bio); 8239 return bio; 8240 } 8241 8242 static inline int btrfs_lookup_and_bind_dio_csum(struct btrfs_root *root, 8243 struct inode *inode, 8244 struct btrfs_dio_private *dip, 8245 struct bio *bio, 8246 u64 file_offset) 8247 { 8248 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 8249 struct btrfs_io_bio *orig_io_bio = btrfs_io_bio(dip->orig_bio); 8250 int ret; 8251 8252 /* 8253 * We load all the csum data we need when we submit 8254 * the first bio to reduce the csum tree search and 8255 * contention. 8256 */ 8257 if (dip->logical_offset == file_offset) { 8258 ret = btrfs_lookup_bio_sums_dio(root, inode, dip->orig_bio, 8259 file_offset); 8260 if (ret) 8261 return ret; 8262 } 8263 8264 if (bio == dip->orig_bio) 8265 return 0; 8266 8267 file_offset -= dip->logical_offset; 8268 file_offset >>= inode->i_sb->s_blocksize_bits; 8269 io_bio->csum = (u8 *)(((u32 *)orig_io_bio->csum) + file_offset); 8270 8271 return 0; 8272 } 8273 8274 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode, 8275 int rw, u64 file_offset, int skip_sum, 8276 int async_submit) 8277 { 8278 struct btrfs_dio_private *dip = bio->bi_private; 8279 int write = rw & REQ_WRITE; 8280 struct btrfs_root *root = BTRFS_I(inode)->root; 8281 int ret; 8282 8283 if (async_submit) 8284 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers); 8285 8286 bio_get(bio); 8287 8288 if (!write) { 8289 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 8290 BTRFS_WQ_ENDIO_DATA); 8291 if (ret) 8292 goto err; 8293 } 8294 8295 if (skip_sum) 8296 goto map; 8297 8298 if (write && async_submit) { 8299 ret = btrfs_wq_submit_bio(root->fs_info, 8300 inode, rw, bio, 0, 0, 8301 file_offset, 8302 __btrfs_submit_bio_start_direct_io, 8303 __btrfs_submit_bio_done); 8304 goto err; 8305 } else if (write) { 8306 /* 8307 * If we aren't doing async submit, calculate the csum of the 8308 * bio now. 8309 */ 8310 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1); 8311 if (ret) 8312 goto err; 8313 } else { 8314 ret = btrfs_lookup_and_bind_dio_csum(root, inode, dip, bio, 8315 file_offset); 8316 if (ret) 8317 goto err; 8318 } 8319 map: 8320 ret = btrfs_map_bio(root, rw, bio, 0, async_submit); 8321 err: 8322 bio_put(bio); 8323 return ret; 8324 } 8325 8326 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, 8327 int skip_sum) 8328 { 8329 struct inode *inode = dip->inode; 8330 struct btrfs_root *root = BTRFS_I(inode)->root; 8331 struct bio *bio; 8332 struct bio *orig_bio = dip->orig_bio; 8333 struct bio_vec *bvec = orig_bio->bi_io_vec; 8334 u64 start_sector = orig_bio->bi_iter.bi_sector; 8335 u64 file_offset = dip->logical_offset; 8336 u64 submit_len = 0; 8337 u64 map_length; 8338 u32 blocksize = root->sectorsize; 8339 int async_submit = 0; 8340 int nr_sectors; 8341 int ret; 8342 int i; 8343 8344 map_length = orig_bio->bi_iter.bi_size; 8345 ret = btrfs_map_block(root->fs_info, rw, start_sector << 9, 8346 &map_length, NULL, 0); 8347 if (ret) 8348 return -EIO; 8349 8350 if (map_length >= orig_bio->bi_iter.bi_size) { 8351 bio = orig_bio; 8352 dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED; 8353 goto submit; 8354 } 8355 8356 /* async crcs make it difficult to collect full stripe writes. */ 8357 if (btrfs_get_alloc_profile(root, 1) & BTRFS_BLOCK_GROUP_RAID56_MASK) 8358 async_submit = 0; 8359 else 8360 async_submit = 1; 8361 8362 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS); 8363 if (!bio) 8364 return -ENOMEM; 8365 8366 bio->bi_private = dip; 8367 bio->bi_end_io = btrfs_end_dio_bio; 8368 btrfs_io_bio(bio)->logical = file_offset; 8369 atomic_inc(&dip->pending_bios); 8370 8371 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) { 8372 nr_sectors = BTRFS_BYTES_TO_BLKS(root->fs_info, bvec->bv_len); 8373 i = 0; 8374 next_block: 8375 if (unlikely(map_length < submit_len + blocksize || 8376 bio_add_page(bio, bvec->bv_page, blocksize, 8377 bvec->bv_offset + (i * blocksize)) < blocksize)) { 8378 /* 8379 * inc the count before we submit the bio so 8380 * we know the end IO handler won't happen before 8381 * we inc the count. Otherwise, the dip might get freed 8382 * before we're done setting it up 8383 */ 8384 atomic_inc(&dip->pending_bios); 8385 ret = __btrfs_submit_dio_bio(bio, inode, rw, 8386 file_offset, skip_sum, 8387 async_submit); 8388 if (ret) { 8389 bio_put(bio); 8390 atomic_dec(&dip->pending_bios); 8391 goto out_err; 8392 } 8393 8394 start_sector += submit_len >> 9; 8395 file_offset += submit_len; 8396 8397 submit_len = 0; 8398 8399 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, 8400 start_sector, GFP_NOFS); 8401 if (!bio) 8402 goto out_err; 8403 bio->bi_private = dip; 8404 bio->bi_end_io = btrfs_end_dio_bio; 8405 btrfs_io_bio(bio)->logical = file_offset; 8406 8407 map_length = orig_bio->bi_iter.bi_size; 8408 ret = btrfs_map_block(root->fs_info, rw, 8409 start_sector << 9, 8410 &map_length, NULL, 0); 8411 if (ret) { 8412 bio_put(bio); 8413 goto out_err; 8414 } 8415 8416 goto next_block; 8417 } else { 8418 submit_len += blocksize; 8419 if (--nr_sectors) { 8420 i++; 8421 goto next_block; 8422 } 8423 bvec++; 8424 } 8425 } 8426 8427 submit: 8428 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum, 8429 async_submit); 8430 if (!ret) 8431 return 0; 8432 8433 bio_put(bio); 8434 out_err: 8435 dip->errors = 1; 8436 /* 8437 * before atomic variable goto zero, we must 8438 * make sure dip->errors is perceived to be set. 8439 */ 8440 smp_mb__before_atomic(); 8441 if (atomic_dec_and_test(&dip->pending_bios)) 8442 bio_io_error(dip->orig_bio); 8443 8444 /* bio_end_io() will handle error, so we needn't return it */ 8445 return 0; 8446 } 8447 8448 static void btrfs_submit_direct(int rw, struct bio *dio_bio, 8449 struct inode *inode, loff_t file_offset) 8450 { 8451 struct btrfs_dio_private *dip = NULL; 8452 struct bio *io_bio = NULL; 8453 struct btrfs_io_bio *btrfs_bio; 8454 int skip_sum; 8455 int write = rw & REQ_WRITE; 8456 int ret = 0; 8457 8458 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 8459 8460 io_bio = btrfs_bio_clone(dio_bio, GFP_NOFS); 8461 if (!io_bio) { 8462 ret = -ENOMEM; 8463 goto free_ordered; 8464 } 8465 8466 dip = kzalloc(sizeof(*dip), GFP_NOFS); 8467 if (!dip) { 8468 ret = -ENOMEM; 8469 goto free_ordered; 8470 } 8471 8472 dip->private = dio_bio->bi_private; 8473 dip->inode = inode; 8474 dip->logical_offset = file_offset; 8475 dip->bytes = dio_bio->bi_iter.bi_size; 8476 dip->disk_bytenr = (u64)dio_bio->bi_iter.bi_sector << 9; 8477 io_bio->bi_private = dip; 8478 dip->orig_bio = io_bio; 8479 dip->dio_bio = dio_bio; 8480 atomic_set(&dip->pending_bios, 0); 8481 btrfs_bio = btrfs_io_bio(io_bio); 8482 btrfs_bio->logical = file_offset; 8483 8484 if (write) { 8485 io_bio->bi_end_io = btrfs_endio_direct_write; 8486 } else { 8487 io_bio->bi_end_io = btrfs_endio_direct_read; 8488 dip->subio_endio = btrfs_subio_endio_read; 8489 } 8490 8491 /* 8492 * Reset the range for unsubmitted ordered extents (to a 0 length range) 8493 * even if we fail to submit a bio, because in such case we do the 8494 * corresponding error handling below and it must not be done a second 8495 * time by btrfs_direct_IO(). 8496 */ 8497 if (write) { 8498 struct btrfs_dio_data *dio_data = current->journal_info; 8499 8500 dio_data->unsubmitted_oe_range_end = dip->logical_offset + 8501 dip->bytes; 8502 dio_data->unsubmitted_oe_range_start = 8503 dio_data->unsubmitted_oe_range_end; 8504 } 8505 8506 ret = btrfs_submit_direct_hook(rw, dip, skip_sum); 8507 if (!ret) 8508 return; 8509 8510 if (btrfs_bio->end_io) 8511 btrfs_bio->end_io(btrfs_bio, ret); 8512 8513 free_ordered: 8514 /* 8515 * If we arrived here it means either we failed to submit the dip 8516 * or we either failed to clone the dio_bio or failed to allocate the 8517 * dip. If we cloned the dio_bio and allocated the dip, we can just 8518 * call bio_endio against our io_bio so that we get proper resource 8519 * cleanup if we fail to submit the dip, otherwise, we must do the 8520 * same as btrfs_endio_direct_[write|read] because we can't call these 8521 * callbacks - they require an allocated dip and a clone of dio_bio. 8522 */ 8523 if (io_bio && dip) { 8524 io_bio->bi_error = -EIO; 8525 bio_endio(io_bio); 8526 /* 8527 * The end io callbacks free our dip, do the final put on io_bio 8528 * and all the cleanup and final put for dio_bio (through 8529 * dio_end_io()). 8530 */ 8531 dip = NULL; 8532 io_bio = NULL; 8533 } else { 8534 if (write) 8535 btrfs_endio_direct_write_update_ordered(inode, 8536 file_offset, 8537 dio_bio->bi_iter.bi_size, 8538 0); 8539 else 8540 unlock_extent(&BTRFS_I(inode)->io_tree, file_offset, 8541 file_offset + dio_bio->bi_iter.bi_size - 1); 8542 8543 dio_bio->bi_error = -EIO; 8544 /* 8545 * Releases and cleans up our dio_bio, no need to bio_put() 8546 * nor bio_endio()/bio_io_error() against dio_bio. 8547 */ 8548 dio_end_io(dio_bio, ret); 8549 } 8550 if (io_bio) 8551 bio_put(io_bio); 8552 kfree(dip); 8553 } 8554 8555 static ssize_t check_direct_IO(struct btrfs_root *root, struct kiocb *iocb, 8556 const struct iov_iter *iter, loff_t offset) 8557 { 8558 int seg; 8559 int i; 8560 unsigned blocksize_mask = root->sectorsize - 1; 8561 ssize_t retval = -EINVAL; 8562 8563 if (offset & blocksize_mask) 8564 goto out; 8565 8566 if (iov_iter_alignment(iter) & blocksize_mask) 8567 goto out; 8568 8569 /* If this is a write we don't need to check anymore */ 8570 if (iov_iter_rw(iter) == WRITE) 8571 return 0; 8572 /* 8573 * Check to make sure we don't have duplicate iov_base's in this 8574 * iovec, if so return EINVAL, otherwise we'll get csum errors 8575 * when reading back. 8576 */ 8577 for (seg = 0; seg < iter->nr_segs; seg++) { 8578 for (i = seg + 1; i < iter->nr_segs; i++) { 8579 if (iter->iov[seg].iov_base == iter->iov[i].iov_base) 8580 goto out; 8581 } 8582 } 8583 retval = 0; 8584 out: 8585 return retval; 8586 } 8587 8588 static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) 8589 { 8590 struct file *file = iocb->ki_filp; 8591 struct inode *inode = file->f_mapping->host; 8592 struct btrfs_root *root = BTRFS_I(inode)->root; 8593 struct btrfs_dio_data dio_data = { 0 }; 8594 loff_t offset = iocb->ki_pos; 8595 size_t count = 0; 8596 int flags = 0; 8597 bool wakeup = true; 8598 bool relock = false; 8599 ssize_t ret; 8600 8601 if (check_direct_IO(BTRFS_I(inode)->root, iocb, iter, offset)) 8602 return 0; 8603 8604 inode_dio_begin(inode); 8605 smp_mb__after_atomic(); 8606 8607 /* 8608 * The generic stuff only does filemap_write_and_wait_range, which 8609 * isn't enough if we've written compressed pages to this area, so 8610 * we need to flush the dirty pages again to make absolutely sure 8611 * that any outstanding dirty pages are on disk. 8612 */ 8613 count = iov_iter_count(iter); 8614 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 8615 &BTRFS_I(inode)->runtime_flags)) 8616 filemap_fdatawrite_range(inode->i_mapping, offset, 8617 offset + count - 1); 8618 8619 if (iov_iter_rw(iter) == WRITE) { 8620 /* 8621 * If the write DIO is beyond the EOF, we need update 8622 * the isize, but it is protected by i_mutex. So we can 8623 * not unlock the i_mutex at this case. 8624 */ 8625 if (offset + count <= inode->i_size) { 8626 inode_unlock(inode); 8627 relock = true; 8628 } 8629 ret = btrfs_delalloc_reserve_space(inode, offset, count); 8630 if (ret) 8631 goto out; 8632 dio_data.outstanding_extents = div64_u64(count + 8633 BTRFS_MAX_EXTENT_SIZE - 1, 8634 BTRFS_MAX_EXTENT_SIZE); 8635 8636 /* 8637 * We need to know how many extents we reserved so that we can 8638 * do the accounting properly if we go over the number we 8639 * originally calculated. Abuse current->journal_info for this. 8640 */ 8641 dio_data.reserve = round_up(count, root->sectorsize); 8642 dio_data.unsubmitted_oe_range_start = (u64)offset; 8643 dio_data.unsubmitted_oe_range_end = (u64)offset; 8644 current->journal_info = &dio_data; 8645 } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK, 8646 &BTRFS_I(inode)->runtime_flags)) { 8647 inode_dio_end(inode); 8648 flags = DIO_LOCKING | DIO_SKIP_HOLES; 8649 wakeup = false; 8650 } 8651 8652 ret = __blockdev_direct_IO(iocb, inode, 8653 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev, 8654 iter, btrfs_get_blocks_direct, NULL, 8655 btrfs_submit_direct, flags); 8656 if (iov_iter_rw(iter) == WRITE) { 8657 current->journal_info = NULL; 8658 if (ret < 0 && ret != -EIOCBQUEUED) { 8659 if (dio_data.reserve) 8660 btrfs_delalloc_release_space(inode, offset, 8661 dio_data.reserve); 8662 /* 8663 * On error we might have left some ordered extents 8664 * without submitting corresponding bios for them, so 8665 * cleanup them up to avoid other tasks getting them 8666 * and waiting for them to complete forever. 8667 */ 8668 if (dio_data.unsubmitted_oe_range_start < 8669 dio_data.unsubmitted_oe_range_end) 8670 btrfs_endio_direct_write_update_ordered(inode, 8671 dio_data.unsubmitted_oe_range_start, 8672 dio_data.unsubmitted_oe_range_end - 8673 dio_data.unsubmitted_oe_range_start, 8674 0); 8675 } else if (ret >= 0 && (size_t)ret < count) 8676 btrfs_delalloc_release_space(inode, offset, 8677 count - (size_t)ret); 8678 } 8679 out: 8680 if (wakeup) 8681 inode_dio_end(inode); 8682 if (relock) 8683 inode_lock(inode); 8684 8685 return ret; 8686 } 8687 8688 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC) 8689 8690 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, 8691 __u64 start, __u64 len) 8692 { 8693 int ret; 8694 8695 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS); 8696 if (ret) 8697 return ret; 8698 8699 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap); 8700 } 8701 8702 int btrfs_readpage(struct file *file, struct page *page) 8703 { 8704 struct extent_io_tree *tree; 8705 tree = &BTRFS_I(page->mapping->host)->io_tree; 8706 return extent_read_full_page(tree, page, btrfs_get_extent, 0); 8707 } 8708 8709 static int btrfs_writepage(struct page *page, struct writeback_control *wbc) 8710 { 8711 struct extent_io_tree *tree; 8712 struct inode *inode = page->mapping->host; 8713 int ret; 8714 8715 if (current->flags & PF_MEMALLOC) { 8716 redirty_page_for_writepage(wbc, page); 8717 unlock_page(page); 8718 return 0; 8719 } 8720 8721 /* 8722 * If we are under memory pressure we will call this directly from the 8723 * VM, we need to make sure we have the inode referenced for the ordered 8724 * extent. If not just return like we didn't do anything. 8725 */ 8726 if (!igrab(inode)) { 8727 redirty_page_for_writepage(wbc, page); 8728 return AOP_WRITEPAGE_ACTIVATE; 8729 } 8730 tree = &BTRFS_I(page->mapping->host)->io_tree; 8731 ret = extent_write_full_page(tree, page, btrfs_get_extent, wbc); 8732 btrfs_add_delayed_iput(inode); 8733 return ret; 8734 } 8735 8736 static int btrfs_writepages(struct address_space *mapping, 8737 struct writeback_control *wbc) 8738 { 8739 struct extent_io_tree *tree; 8740 8741 tree = &BTRFS_I(mapping->host)->io_tree; 8742 return extent_writepages(tree, mapping, btrfs_get_extent, wbc); 8743 } 8744 8745 static int 8746 btrfs_readpages(struct file *file, struct address_space *mapping, 8747 struct list_head *pages, unsigned nr_pages) 8748 { 8749 struct extent_io_tree *tree; 8750 tree = &BTRFS_I(mapping->host)->io_tree; 8751 return extent_readpages(tree, mapping, pages, nr_pages, 8752 btrfs_get_extent); 8753 } 8754 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) 8755 { 8756 struct extent_io_tree *tree; 8757 struct extent_map_tree *map; 8758 int ret; 8759 8760 tree = &BTRFS_I(page->mapping->host)->io_tree; 8761 map = &BTRFS_I(page->mapping->host)->extent_tree; 8762 ret = try_release_extent_mapping(map, tree, page, gfp_flags); 8763 if (ret == 1) { 8764 ClearPagePrivate(page); 8765 set_page_private(page, 0); 8766 put_page(page); 8767 } 8768 return ret; 8769 } 8770 8771 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) 8772 { 8773 if (PageWriteback(page) || PageDirty(page)) 8774 return 0; 8775 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS); 8776 } 8777 8778 static void btrfs_invalidatepage(struct page *page, unsigned int offset, 8779 unsigned int length) 8780 { 8781 struct inode *inode = page->mapping->host; 8782 struct extent_io_tree *tree; 8783 struct btrfs_ordered_extent *ordered; 8784 struct extent_state *cached_state = NULL; 8785 u64 page_start = page_offset(page); 8786 u64 page_end = page_start + PAGE_SIZE - 1; 8787 u64 start; 8788 u64 end; 8789 int inode_evicting = inode->i_state & I_FREEING; 8790 8791 /* 8792 * we have the page locked, so new writeback can't start, 8793 * and the dirty bit won't be cleared while we are here. 8794 * 8795 * Wait for IO on this page so that we can safely clear 8796 * the PagePrivate2 bit and do ordered accounting 8797 */ 8798 wait_on_page_writeback(page); 8799 8800 tree = &BTRFS_I(inode)->io_tree; 8801 if (offset) { 8802 btrfs_releasepage(page, GFP_NOFS); 8803 return; 8804 } 8805 8806 if (!inode_evicting) 8807 lock_extent_bits(tree, page_start, page_end, &cached_state); 8808 again: 8809 start = page_start; 8810 ordered = btrfs_lookup_ordered_range(inode, start, 8811 page_end - start + 1); 8812 if (ordered) { 8813 end = min(page_end, ordered->file_offset + ordered->len - 1); 8814 /* 8815 * IO on this page will never be started, so we need 8816 * to account for any ordered extents now 8817 */ 8818 if (!inode_evicting) 8819 clear_extent_bit(tree, start, end, 8820 EXTENT_DIRTY | EXTENT_DELALLOC | 8821 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING | 8822 EXTENT_DEFRAG, 1, 0, &cached_state, 8823 GFP_NOFS); 8824 /* 8825 * whoever cleared the private bit is responsible 8826 * for the finish_ordered_io 8827 */ 8828 if (TestClearPagePrivate2(page)) { 8829 struct btrfs_ordered_inode_tree *tree; 8830 u64 new_len; 8831 8832 tree = &BTRFS_I(inode)->ordered_tree; 8833 8834 spin_lock_irq(&tree->lock); 8835 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); 8836 new_len = start - ordered->file_offset; 8837 if (new_len < ordered->truncated_len) 8838 ordered->truncated_len = new_len; 8839 spin_unlock_irq(&tree->lock); 8840 8841 if (btrfs_dec_test_ordered_pending(inode, &ordered, 8842 start, 8843 end - start + 1, 1)) 8844 btrfs_finish_ordered_io(ordered); 8845 } 8846 btrfs_put_ordered_extent(ordered); 8847 if (!inode_evicting) { 8848 cached_state = NULL; 8849 lock_extent_bits(tree, start, end, 8850 &cached_state); 8851 } 8852 8853 start = end + 1; 8854 if (start < page_end) 8855 goto again; 8856 } 8857 8858 /* 8859 * Qgroup reserved space handler 8860 * Page here will be either 8861 * 1) Already written to disk 8862 * In this case, its reserved space is released from data rsv map 8863 * and will be freed by delayed_ref handler finally. 8864 * So even we call qgroup_free_data(), it won't decrease reserved 8865 * space. 8866 * 2) Not written to disk 8867 * This means the reserved space should be freed here. 8868 */ 8869 btrfs_qgroup_free_data(inode, page_start, PAGE_SIZE); 8870 if (!inode_evicting) { 8871 clear_extent_bit(tree, page_start, page_end, 8872 EXTENT_LOCKED | EXTENT_DIRTY | 8873 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | 8874 EXTENT_DEFRAG, 1, 1, 8875 &cached_state, GFP_NOFS); 8876 8877 __btrfs_releasepage(page, GFP_NOFS); 8878 } 8879 8880 ClearPageChecked(page); 8881 if (PagePrivate(page)) { 8882 ClearPagePrivate(page); 8883 set_page_private(page, 0); 8884 put_page(page); 8885 } 8886 } 8887 8888 /* 8889 * btrfs_page_mkwrite() is not allowed to change the file size as it gets 8890 * called from a page fault handler when a page is first dirtied. Hence we must 8891 * be careful to check for EOF conditions here. We set the page up correctly 8892 * for a written page which means we get ENOSPC checking when writing into 8893 * holes and correct delalloc and unwritten extent mapping on filesystems that 8894 * support these features. 8895 * 8896 * We are not allowed to take the i_mutex here so we have to play games to 8897 * protect against truncate races as the page could now be beyond EOF. Because 8898 * vmtruncate() writes the inode size before removing pages, once we have the 8899 * page lock we can determine safely if the page is beyond EOF. If it is not 8900 * beyond EOF, then the page is guaranteed safe against truncation until we 8901 * unlock the page. 8902 */ 8903 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 8904 { 8905 struct page *page = vmf->page; 8906 struct inode *inode = file_inode(vma->vm_file); 8907 struct btrfs_root *root = BTRFS_I(inode)->root; 8908 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 8909 struct btrfs_ordered_extent *ordered; 8910 struct extent_state *cached_state = NULL; 8911 char *kaddr; 8912 unsigned long zero_start; 8913 loff_t size; 8914 int ret; 8915 int reserved = 0; 8916 u64 reserved_space; 8917 u64 page_start; 8918 u64 page_end; 8919 u64 end; 8920 8921 reserved_space = PAGE_SIZE; 8922 8923 sb_start_pagefault(inode->i_sb); 8924 page_start = page_offset(page); 8925 page_end = page_start + PAGE_SIZE - 1; 8926 end = page_end; 8927 8928 /* 8929 * Reserving delalloc space after obtaining the page lock can lead to 8930 * deadlock. For example, if a dirty page is locked by this function 8931 * and the call to btrfs_delalloc_reserve_space() ends up triggering 8932 * dirty page write out, then the btrfs_writepage() function could 8933 * end up waiting indefinitely to get a lock on the page currently 8934 * being processed by btrfs_page_mkwrite() function. 8935 */ 8936 ret = btrfs_delalloc_reserve_space(inode, page_start, 8937 reserved_space); 8938 if (!ret) { 8939 ret = file_update_time(vma->vm_file); 8940 reserved = 1; 8941 } 8942 if (ret) { 8943 if (ret == -ENOMEM) 8944 ret = VM_FAULT_OOM; 8945 else /* -ENOSPC, -EIO, etc */ 8946 ret = VM_FAULT_SIGBUS; 8947 if (reserved) 8948 goto out; 8949 goto out_noreserve; 8950 } 8951 8952 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ 8953 again: 8954 lock_page(page); 8955 size = i_size_read(inode); 8956 8957 if ((page->mapping != inode->i_mapping) || 8958 (page_start >= size)) { 8959 /* page got truncated out from underneath us */ 8960 goto out_unlock; 8961 } 8962 wait_on_page_writeback(page); 8963 8964 lock_extent_bits(io_tree, page_start, page_end, &cached_state); 8965 set_page_extent_mapped(page); 8966 8967 /* 8968 * we can't set the delalloc bits if there are pending ordered 8969 * extents. Drop our locks and wait for them to finish 8970 */ 8971 ordered = btrfs_lookup_ordered_range(inode, page_start, page_end); 8972 if (ordered) { 8973 unlock_extent_cached(io_tree, page_start, page_end, 8974 &cached_state, GFP_NOFS); 8975 unlock_page(page); 8976 btrfs_start_ordered_extent(inode, ordered, 1); 8977 btrfs_put_ordered_extent(ordered); 8978 goto again; 8979 } 8980 8981 if (page->index == ((size - 1) >> PAGE_SHIFT)) { 8982 reserved_space = round_up(size - page_start, root->sectorsize); 8983 if (reserved_space < PAGE_SIZE) { 8984 end = page_start + reserved_space - 1; 8985 spin_lock(&BTRFS_I(inode)->lock); 8986 BTRFS_I(inode)->outstanding_extents++; 8987 spin_unlock(&BTRFS_I(inode)->lock); 8988 btrfs_delalloc_release_space(inode, page_start, 8989 PAGE_SIZE - reserved_space); 8990 } 8991 } 8992 8993 /* 8994 * XXX - page_mkwrite gets called every time the page is dirtied, even 8995 * if it was already dirty, so for space accounting reasons we need to 8996 * clear any delalloc bits for the range we are fixing to save. There 8997 * is probably a better way to do this, but for now keep consistent with 8998 * prepare_pages in the normal write path. 8999 */ 9000 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, end, 9001 EXTENT_DIRTY | EXTENT_DELALLOC | 9002 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 9003 0, 0, &cached_state, GFP_NOFS); 9004 9005 ret = btrfs_set_extent_delalloc(inode, page_start, end, 9006 &cached_state); 9007 if (ret) { 9008 unlock_extent_cached(io_tree, page_start, page_end, 9009 &cached_state, GFP_NOFS); 9010 ret = VM_FAULT_SIGBUS; 9011 goto out_unlock; 9012 } 9013 ret = 0; 9014 9015 /* page is wholly or partially inside EOF */ 9016 if (page_start + PAGE_SIZE > size) 9017 zero_start = size & ~PAGE_MASK; 9018 else 9019 zero_start = PAGE_SIZE; 9020 9021 if (zero_start != PAGE_SIZE) { 9022 kaddr = kmap(page); 9023 memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start); 9024 flush_dcache_page(page); 9025 kunmap(page); 9026 } 9027 ClearPageChecked(page); 9028 set_page_dirty(page); 9029 SetPageUptodate(page); 9030 9031 BTRFS_I(inode)->last_trans = root->fs_info->generation; 9032 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid; 9033 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit; 9034 9035 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS); 9036 9037 out_unlock: 9038 if (!ret) { 9039 sb_end_pagefault(inode->i_sb); 9040 return VM_FAULT_LOCKED; 9041 } 9042 unlock_page(page); 9043 out: 9044 btrfs_delalloc_release_space(inode, page_start, reserved_space); 9045 out_noreserve: 9046 sb_end_pagefault(inode->i_sb); 9047 return ret; 9048 } 9049 9050 static int btrfs_truncate(struct inode *inode) 9051 { 9052 struct btrfs_root *root = BTRFS_I(inode)->root; 9053 struct btrfs_block_rsv *rsv; 9054 int ret = 0; 9055 int err = 0; 9056 struct btrfs_trans_handle *trans; 9057 u64 mask = root->sectorsize - 1; 9058 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); 9059 9060 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask), 9061 (u64)-1); 9062 if (ret) 9063 return ret; 9064 9065 /* 9066 * Yes ladies and gentlemen, this is indeed ugly. The fact is we have 9067 * 3 things going on here 9068 * 9069 * 1) We need to reserve space for our orphan item and the space to 9070 * delete our orphan item. Lord knows we don't want to have a dangling 9071 * orphan item because we didn't reserve space to remove it. 9072 * 9073 * 2) We need to reserve space to update our inode. 9074 * 9075 * 3) We need to have something to cache all the space that is going to 9076 * be free'd up by the truncate operation, but also have some slack 9077 * space reserved in case it uses space during the truncate (thank you 9078 * very much snapshotting). 9079 * 9080 * And we need these to all be separate. The fact is we can use a lot of 9081 * space doing the truncate, and we have no earthly idea how much space 9082 * we will use, so we need the truncate reservation to be separate so it 9083 * doesn't end up using space reserved for updating the inode or 9084 * removing the orphan item. We also need to be able to stop the 9085 * transaction and start a new one, which means we need to be able to 9086 * update the inode several times, and we have no idea of knowing how 9087 * many times that will be, so we can't just reserve 1 item for the 9088 * entirety of the operation, so that has to be done separately as well. 9089 * Then there is the orphan item, which does indeed need to be held on 9090 * to for the whole operation, and we need nobody to touch this reserved 9091 * space except the orphan code. 9092 * 9093 * So that leaves us with 9094 * 9095 * 1) root->orphan_block_rsv - for the orphan deletion. 9096 * 2) rsv - for the truncate reservation, which we will steal from the 9097 * transaction reservation. 9098 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for 9099 * updating the inode. 9100 */ 9101 rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP); 9102 if (!rsv) 9103 return -ENOMEM; 9104 rsv->size = min_size; 9105 rsv->failfast = 1; 9106 9107 /* 9108 * 1 for the truncate slack space 9109 * 1 for updating the inode. 9110 */ 9111 trans = btrfs_start_transaction(root, 2); 9112 if (IS_ERR(trans)) { 9113 err = PTR_ERR(trans); 9114 goto out; 9115 } 9116 9117 /* Migrate the slack space for the truncate to our reserve */ 9118 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv, 9119 min_size); 9120 BUG_ON(ret); 9121 9122 /* 9123 * So if we truncate and then write and fsync we normally would just 9124 * write the extents that changed, which is a problem if we need to 9125 * first truncate that entire inode. So set this flag so we write out 9126 * all of the extents in the inode to the sync log so we're completely 9127 * safe. 9128 */ 9129 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 9130 trans->block_rsv = rsv; 9131 9132 while (1) { 9133 ret = btrfs_truncate_inode_items(trans, root, inode, 9134 inode->i_size, 9135 BTRFS_EXTENT_DATA_KEY); 9136 if (ret != -ENOSPC && ret != -EAGAIN) { 9137 err = ret; 9138 break; 9139 } 9140 9141 trans->block_rsv = &root->fs_info->trans_block_rsv; 9142 ret = btrfs_update_inode(trans, root, inode); 9143 if (ret) { 9144 err = ret; 9145 break; 9146 } 9147 9148 btrfs_end_transaction(trans, root); 9149 btrfs_btree_balance_dirty(root); 9150 9151 trans = btrfs_start_transaction(root, 2); 9152 if (IS_ERR(trans)) { 9153 ret = err = PTR_ERR(trans); 9154 trans = NULL; 9155 break; 9156 } 9157 9158 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, 9159 rsv, min_size); 9160 BUG_ON(ret); /* shouldn't happen */ 9161 trans->block_rsv = rsv; 9162 } 9163 9164 if (ret == 0 && inode->i_nlink > 0) { 9165 trans->block_rsv = root->orphan_block_rsv; 9166 ret = btrfs_orphan_del(trans, inode); 9167 if (ret) 9168 err = ret; 9169 } 9170 9171 if (trans) { 9172 trans->block_rsv = &root->fs_info->trans_block_rsv; 9173 ret = btrfs_update_inode(trans, root, inode); 9174 if (ret && !err) 9175 err = ret; 9176 9177 ret = btrfs_end_transaction(trans, root); 9178 btrfs_btree_balance_dirty(root); 9179 } 9180 9181 out: 9182 btrfs_free_block_rsv(root, rsv); 9183 9184 if (ret && !err) 9185 err = ret; 9186 9187 return err; 9188 } 9189 9190 /* 9191 * create a new subvolume directory/inode (helper for the ioctl). 9192 */ 9193 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, 9194 struct btrfs_root *new_root, 9195 struct btrfs_root *parent_root, 9196 u64 new_dirid) 9197 { 9198 struct inode *inode; 9199 int err; 9200 u64 index = 0; 9201 9202 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, 9203 new_dirid, new_dirid, 9204 S_IFDIR | (~current_umask() & S_IRWXUGO), 9205 &index); 9206 if (IS_ERR(inode)) 9207 return PTR_ERR(inode); 9208 inode->i_op = &btrfs_dir_inode_operations; 9209 inode->i_fop = &btrfs_dir_file_operations; 9210 9211 set_nlink(inode, 1); 9212 btrfs_i_size_write(inode, 0); 9213 unlock_new_inode(inode); 9214 9215 err = btrfs_subvol_inherit_props(trans, new_root, parent_root); 9216 if (err) 9217 btrfs_err(new_root->fs_info, 9218 "error inheriting subvolume %llu properties: %d", 9219 new_root->root_key.objectid, err); 9220 9221 err = btrfs_update_inode(trans, new_root, inode); 9222 9223 iput(inode); 9224 return err; 9225 } 9226 9227 struct inode *btrfs_alloc_inode(struct super_block *sb) 9228 { 9229 struct btrfs_inode *ei; 9230 struct inode *inode; 9231 9232 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS); 9233 if (!ei) 9234 return NULL; 9235 9236 ei->root = NULL; 9237 ei->generation = 0; 9238 ei->last_trans = 0; 9239 ei->last_sub_trans = 0; 9240 ei->logged_trans = 0; 9241 ei->delalloc_bytes = 0; 9242 ei->defrag_bytes = 0; 9243 ei->disk_i_size = 0; 9244 ei->flags = 0; 9245 ei->csum_bytes = 0; 9246 ei->index_cnt = (u64)-1; 9247 ei->dir_index = 0; 9248 ei->last_unlink_trans = 0; 9249 ei->last_log_commit = 0; 9250 ei->delayed_iput_count = 0; 9251 9252 spin_lock_init(&ei->lock); 9253 ei->outstanding_extents = 0; 9254 ei->reserved_extents = 0; 9255 9256 ei->runtime_flags = 0; 9257 ei->force_compress = BTRFS_COMPRESS_NONE; 9258 9259 ei->delayed_node = NULL; 9260 9261 ei->i_otime.tv_sec = 0; 9262 ei->i_otime.tv_nsec = 0; 9263 9264 inode = &ei->vfs_inode; 9265 extent_map_tree_init(&ei->extent_tree); 9266 extent_io_tree_init(&ei->io_tree, &inode->i_data); 9267 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data); 9268 ei->io_tree.track_uptodate = 1; 9269 ei->io_failure_tree.track_uptodate = 1; 9270 atomic_set(&ei->sync_writers, 0); 9271 mutex_init(&ei->log_mutex); 9272 mutex_init(&ei->delalloc_mutex); 9273 btrfs_ordered_inode_tree_init(&ei->ordered_tree); 9274 INIT_LIST_HEAD(&ei->delalloc_inodes); 9275 INIT_LIST_HEAD(&ei->delayed_iput); 9276 RB_CLEAR_NODE(&ei->rb_node); 9277 init_rwsem(&ei->dio_sem); 9278 9279 return inode; 9280 } 9281 9282 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 9283 void btrfs_test_destroy_inode(struct inode *inode) 9284 { 9285 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0); 9286 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); 9287 } 9288 #endif 9289 9290 static void btrfs_i_callback(struct rcu_head *head) 9291 { 9292 struct inode *inode = container_of(head, struct inode, i_rcu); 9293 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); 9294 } 9295 9296 void btrfs_destroy_inode(struct inode *inode) 9297 { 9298 struct btrfs_ordered_extent *ordered; 9299 struct btrfs_root *root = BTRFS_I(inode)->root; 9300 9301 WARN_ON(!hlist_empty(&inode->i_dentry)); 9302 WARN_ON(inode->i_data.nrpages); 9303 WARN_ON(BTRFS_I(inode)->outstanding_extents); 9304 WARN_ON(BTRFS_I(inode)->reserved_extents); 9305 WARN_ON(BTRFS_I(inode)->delalloc_bytes); 9306 WARN_ON(BTRFS_I(inode)->csum_bytes); 9307 WARN_ON(BTRFS_I(inode)->defrag_bytes); 9308 9309 /* 9310 * This can happen where we create an inode, but somebody else also 9311 * created the same inode and we need to destroy the one we already 9312 * created. 9313 */ 9314 if (!root) 9315 goto free; 9316 9317 if (test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, 9318 &BTRFS_I(inode)->runtime_flags)) { 9319 btrfs_info(root->fs_info, "inode %llu still on the orphan list", 9320 btrfs_ino(inode)); 9321 atomic_dec(&root->orphan_inodes); 9322 } 9323 9324 while (1) { 9325 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1); 9326 if (!ordered) 9327 break; 9328 else { 9329 btrfs_err(root->fs_info, "found ordered extent %llu %llu on inode cleanup", 9330 ordered->file_offset, ordered->len); 9331 btrfs_remove_ordered_extent(inode, ordered); 9332 btrfs_put_ordered_extent(ordered); 9333 btrfs_put_ordered_extent(ordered); 9334 } 9335 } 9336 btrfs_qgroup_check_reserved_leak(inode); 9337 inode_tree_del(inode); 9338 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0); 9339 free: 9340 call_rcu(&inode->i_rcu, btrfs_i_callback); 9341 } 9342 9343 int btrfs_drop_inode(struct inode *inode) 9344 { 9345 struct btrfs_root *root = BTRFS_I(inode)->root; 9346 9347 if (root == NULL) 9348 return 1; 9349 9350 /* the snap/subvol tree is on deleting */ 9351 if (btrfs_root_refs(&root->root_item) == 0) 9352 return 1; 9353 else 9354 return generic_drop_inode(inode); 9355 } 9356 9357 static void init_once(void *foo) 9358 { 9359 struct btrfs_inode *ei = (struct btrfs_inode *) foo; 9360 9361 inode_init_once(&ei->vfs_inode); 9362 } 9363 9364 void btrfs_destroy_cachep(void) 9365 { 9366 /* 9367 * Make sure all delayed rcu free inodes are flushed before we 9368 * destroy cache. 9369 */ 9370 rcu_barrier(); 9371 kmem_cache_destroy(btrfs_inode_cachep); 9372 kmem_cache_destroy(btrfs_trans_handle_cachep); 9373 kmem_cache_destroy(btrfs_transaction_cachep); 9374 kmem_cache_destroy(btrfs_path_cachep); 9375 kmem_cache_destroy(btrfs_free_space_cachep); 9376 } 9377 9378 int btrfs_init_cachep(void) 9379 { 9380 btrfs_inode_cachep = kmem_cache_create("btrfs_inode", 9381 sizeof(struct btrfs_inode), 0, 9382 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT, 9383 init_once); 9384 if (!btrfs_inode_cachep) 9385 goto fail; 9386 9387 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle", 9388 sizeof(struct btrfs_trans_handle), 0, 9389 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); 9390 if (!btrfs_trans_handle_cachep) 9391 goto fail; 9392 9393 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction", 9394 sizeof(struct btrfs_transaction), 0, 9395 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); 9396 if (!btrfs_transaction_cachep) 9397 goto fail; 9398 9399 btrfs_path_cachep = kmem_cache_create("btrfs_path", 9400 sizeof(struct btrfs_path), 0, 9401 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); 9402 if (!btrfs_path_cachep) 9403 goto fail; 9404 9405 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space", 9406 sizeof(struct btrfs_free_space), 0, 9407 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); 9408 if (!btrfs_free_space_cachep) 9409 goto fail; 9410 9411 return 0; 9412 fail: 9413 btrfs_destroy_cachep(); 9414 return -ENOMEM; 9415 } 9416 9417 static int btrfs_getattr(struct vfsmount *mnt, 9418 struct dentry *dentry, struct kstat *stat) 9419 { 9420 u64 delalloc_bytes; 9421 struct inode *inode = d_inode(dentry); 9422 u32 blocksize = inode->i_sb->s_blocksize; 9423 9424 generic_fillattr(inode, stat); 9425 stat->dev = BTRFS_I(inode)->root->anon_dev; 9426 9427 spin_lock(&BTRFS_I(inode)->lock); 9428 delalloc_bytes = BTRFS_I(inode)->delalloc_bytes; 9429 spin_unlock(&BTRFS_I(inode)->lock); 9430 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) + 9431 ALIGN(delalloc_bytes, blocksize)) >> 9; 9432 return 0; 9433 } 9434 9435 static int btrfs_rename_exchange(struct inode *old_dir, 9436 struct dentry *old_dentry, 9437 struct inode *new_dir, 9438 struct dentry *new_dentry) 9439 { 9440 struct btrfs_trans_handle *trans; 9441 struct btrfs_root *root = BTRFS_I(old_dir)->root; 9442 struct btrfs_root *dest = BTRFS_I(new_dir)->root; 9443 struct inode *new_inode = new_dentry->d_inode; 9444 struct inode *old_inode = old_dentry->d_inode; 9445 struct timespec ctime = CURRENT_TIME; 9446 struct dentry *parent; 9447 u64 old_ino = btrfs_ino(old_inode); 9448 u64 new_ino = btrfs_ino(new_inode); 9449 u64 old_idx = 0; 9450 u64 new_idx = 0; 9451 u64 root_objectid; 9452 int ret; 9453 bool root_log_pinned = false; 9454 bool dest_log_pinned = false; 9455 9456 /* we only allow rename subvolume link between subvolumes */ 9457 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) 9458 return -EXDEV; 9459 9460 /* close the race window with snapshot create/destroy ioctl */ 9461 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9462 down_read(&root->fs_info->subvol_sem); 9463 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) 9464 down_read(&dest->fs_info->subvol_sem); 9465 9466 /* 9467 * We want to reserve the absolute worst case amount of items. So if 9468 * both inodes are subvols and we need to unlink them then that would 9469 * require 4 item modifications, but if they are both normal inodes it 9470 * would require 5 item modifications, so we'll assume their normal 9471 * inodes. So 5 * 2 is 10, plus 2 for the new links, so 12 total items 9472 * should cover the worst case number of items we'll modify. 9473 */ 9474 trans = btrfs_start_transaction(root, 12); 9475 if (IS_ERR(trans)) { 9476 ret = PTR_ERR(trans); 9477 goto out_notrans; 9478 } 9479 9480 /* 9481 * We need to find a free sequence number both in the source and 9482 * in the destination directory for the exchange. 9483 */ 9484 ret = btrfs_set_inode_index(new_dir, &old_idx); 9485 if (ret) 9486 goto out_fail; 9487 ret = btrfs_set_inode_index(old_dir, &new_idx); 9488 if (ret) 9489 goto out_fail; 9490 9491 BTRFS_I(old_inode)->dir_index = 0ULL; 9492 BTRFS_I(new_inode)->dir_index = 0ULL; 9493 9494 /* Reference for the source. */ 9495 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { 9496 /* force full log commit if subvolume involved. */ 9497 btrfs_set_log_full_commit(root->fs_info, trans); 9498 } else { 9499 btrfs_pin_log_trans(root); 9500 root_log_pinned = true; 9501 ret = btrfs_insert_inode_ref(trans, dest, 9502 new_dentry->d_name.name, 9503 new_dentry->d_name.len, 9504 old_ino, 9505 btrfs_ino(new_dir), old_idx); 9506 if (ret) 9507 goto out_fail; 9508 } 9509 9510 /* And now for the dest. */ 9511 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { 9512 /* force full log commit if subvolume involved. */ 9513 btrfs_set_log_full_commit(dest->fs_info, trans); 9514 } else { 9515 btrfs_pin_log_trans(dest); 9516 dest_log_pinned = true; 9517 ret = btrfs_insert_inode_ref(trans, root, 9518 old_dentry->d_name.name, 9519 old_dentry->d_name.len, 9520 new_ino, 9521 btrfs_ino(old_dir), new_idx); 9522 if (ret) 9523 goto out_fail; 9524 } 9525 9526 /* Update inode version and ctime/mtime. */ 9527 inode_inc_iversion(old_dir); 9528 inode_inc_iversion(new_dir); 9529 inode_inc_iversion(old_inode); 9530 inode_inc_iversion(new_inode); 9531 old_dir->i_ctime = old_dir->i_mtime = ctime; 9532 new_dir->i_ctime = new_dir->i_mtime = ctime; 9533 old_inode->i_ctime = ctime; 9534 new_inode->i_ctime = ctime; 9535 9536 if (old_dentry->d_parent != new_dentry->d_parent) { 9537 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1); 9538 btrfs_record_unlink_dir(trans, new_dir, new_inode, 1); 9539 } 9540 9541 /* src is a subvolume */ 9542 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { 9543 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; 9544 ret = btrfs_unlink_subvol(trans, root, old_dir, 9545 root_objectid, 9546 old_dentry->d_name.name, 9547 old_dentry->d_name.len); 9548 } else { /* src is an inode */ 9549 ret = __btrfs_unlink_inode(trans, root, old_dir, 9550 old_dentry->d_inode, 9551 old_dentry->d_name.name, 9552 old_dentry->d_name.len); 9553 if (!ret) 9554 ret = btrfs_update_inode(trans, root, old_inode); 9555 } 9556 if (ret) { 9557 btrfs_abort_transaction(trans, root, ret); 9558 goto out_fail; 9559 } 9560 9561 /* dest is a subvolume */ 9562 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { 9563 root_objectid = BTRFS_I(new_inode)->root->root_key.objectid; 9564 ret = btrfs_unlink_subvol(trans, dest, new_dir, 9565 root_objectid, 9566 new_dentry->d_name.name, 9567 new_dentry->d_name.len); 9568 } else { /* dest is an inode */ 9569 ret = __btrfs_unlink_inode(trans, dest, new_dir, 9570 new_dentry->d_inode, 9571 new_dentry->d_name.name, 9572 new_dentry->d_name.len); 9573 if (!ret) 9574 ret = btrfs_update_inode(trans, dest, new_inode); 9575 } 9576 if (ret) { 9577 btrfs_abort_transaction(trans, root, ret); 9578 goto out_fail; 9579 } 9580 9581 ret = btrfs_add_link(trans, new_dir, old_inode, 9582 new_dentry->d_name.name, 9583 new_dentry->d_name.len, 0, old_idx); 9584 if (ret) { 9585 btrfs_abort_transaction(trans, root, ret); 9586 goto out_fail; 9587 } 9588 9589 ret = btrfs_add_link(trans, old_dir, new_inode, 9590 old_dentry->d_name.name, 9591 old_dentry->d_name.len, 0, new_idx); 9592 if (ret) { 9593 btrfs_abort_transaction(trans, root, ret); 9594 goto out_fail; 9595 } 9596 9597 if (old_inode->i_nlink == 1) 9598 BTRFS_I(old_inode)->dir_index = old_idx; 9599 if (new_inode->i_nlink == 1) 9600 BTRFS_I(new_inode)->dir_index = new_idx; 9601 9602 if (root_log_pinned) { 9603 parent = new_dentry->d_parent; 9604 btrfs_log_new_name(trans, old_inode, old_dir, parent); 9605 btrfs_end_log_trans(root); 9606 root_log_pinned = false; 9607 } 9608 if (dest_log_pinned) { 9609 parent = old_dentry->d_parent; 9610 btrfs_log_new_name(trans, new_inode, new_dir, parent); 9611 btrfs_end_log_trans(dest); 9612 dest_log_pinned = false; 9613 } 9614 out_fail: 9615 /* 9616 * If we have pinned a log and an error happened, we unpin tasks 9617 * trying to sync the log and force them to fallback to a transaction 9618 * commit if the log currently contains any of the inodes involved in 9619 * this rename operation (to ensure we do not persist a log with an 9620 * inconsistent state for any of these inodes or leading to any 9621 * inconsistencies when replayed). If the transaction was aborted, the 9622 * abortion reason is propagated to userspace when attempting to commit 9623 * the transaction. If the log does not contain any of these inodes, we 9624 * allow the tasks to sync it. 9625 */ 9626 if (ret && (root_log_pinned || dest_log_pinned)) { 9627 if (btrfs_inode_in_log(old_dir, root->fs_info->generation) || 9628 btrfs_inode_in_log(new_dir, root->fs_info->generation) || 9629 btrfs_inode_in_log(old_inode, root->fs_info->generation) || 9630 (new_inode && 9631 btrfs_inode_in_log(new_inode, root->fs_info->generation))) 9632 btrfs_set_log_full_commit(root->fs_info, trans); 9633 9634 if (root_log_pinned) { 9635 btrfs_end_log_trans(root); 9636 root_log_pinned = false; 9637 } 9638 if (dest_log_pinned) { 9639 btrfs_end_log_trans(dest); 9640 dest_log_pinned = false; 9641 } 9642 } 9643 ret = btrfs_end_transaction(trans, root); 9644 out_notrans: 9645 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) 9646 up_read(&dest->fs_info->subvol_sem); 9647 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9648 up_read(&root->fs_info->subvol_sem); 9649 9650 return ret; 9651 } 9652 9653 static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans, 9654 struct btrfs_root *root, 9655 struct inode *dir, 9656 struct dentry *dentry) 9657 { 9658 int ret; 9659 struct inode *inode; 9660 u64 objectid; 9661 u64 index; 9662 9663 ret = btrfs_find_free_ino(root, &objectid); 9664 if (ret) 9665 return ret; 9666 9667 inode = btrfs_new_inode(trans, root, dir, 9668 dentry->d_name.name, 9669 dentry->d_name.len, 9670 btrfs_ino(dir), 9671 objectid, 9672 S_IFCHR | WHITEOUT_MODE, 9673 &index); 9674 9675 if (IS_ERR(inode)) { 9676 ret = PTR_ERR(inode); 9677 return ret; 9678 } 9679 9680 inode->i_op = &btrfs_special_inode_operations; 9681 init_special_inode(inode, inode->i_mode, 9682 WHITEOUT_DEV); 9683 9684 ret = btrfs_init_inode_security(trans, inode, dir, 9685 &dentry->d_name); 9686 if (ret) 9687 goto out; 9688 9689 ret = btrfs_add_nondir(trans, dir, dentry, 9690 inode, 0, index); 9691 if (ret) 9692 goto out; 9693 9694 ret = btrfs_update_inode(trans, root, inode); 9695 out: 9696 unlock_new_inode(inode); 9697 if (ret) 9698 inode_dec_link_count(inode); 9699 iput(inode); 9700 9701 return ret; 9702 } 9703 9704 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, 9705 struct inode *new_dir, struct dentry *new_dentry, 9706 unsigned int flags) 9707 { 9708 struct btrfs_trans_handle *trans; 9709 unsigned int trans_num_items; 9710 struct btrfs_root *root = BTRFS_I(old_dir)->root; 9711 struct btrfs_root *dest = BTRFS_I(new_dir)->root; 9712 struct inode *new_inode = d_inode(new_dentry); 9713 struct inode *old_inode = d_inode(old_dentry); 9714 u64 index = 0; 9715 u64 root_objectid; 9716 int ret; 9717 u64 old_ino = btrfs_ino(old_inode); 9718 bool log_pinned = false; 9719 9720 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) 9721 return -EPERM; 9722 9723 /* we only allow rename subvolume link between subvolumes */ 9724 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) 9725 return -EXDEV; 9726 9727 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || 9728 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID)) 9729 return -ENOTEMPTY; 9730 9731 if (S_ISDIR(old_inode->i_mode) && new_inode && 9732 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) 9733 return -ENOTEMPTY; 9734 9735 9736 /* check for collisions, even if the name isn't there */ 9737 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino, 9738 new_dentry->d_name.name, 9739 new_dentry->d_name.len); 9740 9741 if (ret) { 9742 if (ret == -EEXIST) { 9743 /* we shouldn't get 9744 * eexist without a new_inode */ 9745 if (WARN_ON(!new_inode)) { 9746 return ret; 9747 } 9748 } else { 9749 /* maybe -EOVERFLOW */ 9750 return ret; 9751 } 9752 } 9753 ret = 0; 9754 9755 /* 9756 * we're using rename to replace one file with another. Start IO on it 9757 * now so we don't add too much work to the end of the transaction 9758 */ 9759 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size) 9760 filemap_flush(old_inode->i_mapping); 9761 9762 /* close the racy window with snapshot create/destroy ioctl */ 9763 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9764 down_read(&root->fs_info->subvol_sem); 9765 /* 9766 * We want to reserve the absolute worst case amount of items. So if 9767 * both inodes are subvols and we need to unlink them then that would 9768 * require 4 item modifications, but if they are both normal inodes it 9769 * would require 5 item modifications, so we'll assume they are normal 9770 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items 9771 * should cover the worst case number of items we'll modify. 9772 * If our rename has the whiteout flag, we need more 5 units for the 9773 * new inode (1 inode item, 1 inode ref, 2 dir items and 1 xattr item 9774 * when selinux is enabled). 9775 */ 9776 trans_num_items = 11; 9777 if (flags & RENAME_WHITEOUT) 9778 trans_num_items += 5; 9779 trans = btrfs_start_transaction(root, trans_num_items); 9780 if (IS_ERR(trans)) { 9781 ret = PTR_ERR(trans); 9782 goto out_notrans; 9783 } 9784 9785 if (dest != root) 9786 btrfs_record_root_in_trans(trans, dest); 9787 9788 ret = btrfs_set_inode_index(new_dir, &index); 9789 if (ret) 9790 goto out_fail; 9791 9792 BTRFS_I(old_inode)->dir_index = 0ULL; 9793 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { 9794 /* force full log commit if subvolume involved. */ 9795 btrfs_set_log_full_commit(root->fs_info, trans); 9796 } else { 9797 btrfs_pin_log_trans(root); 9798 log_pinned = true; 9799 ret = btrfs_insert_inode_ref(trans, dest, 9800 new_dentry->d_name.name, 9801 new_dentry->d_name.len, 9802 old_ino, 9803 btrfs_ino(new_dir), index); 9804 if (ret) 9805 goto out_fail; 9806 } 9807 9808 inode_inc_iversion(old_dir); 9809 inode_inc_iversion(new_dir); 9810 inode_inc_iversion(old_inode); 9811 old_dir->i_ctime = old_dir->i_mtime = 9812 new_dir->i_ctime = new_dir->i_mtime = 9813 old_inode->i_ctime = current_fs_time(old_dir->i_sb); 9814 9815 if (old_dentry->d_parent != new_dentry->d_parent) 9816 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1); 9817 9818 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { 9819 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; 9820 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid, 9821 old_dentry->d_name.name, 9822 old_dentry->d_name.len); 9823 } else { 9824 ret = __btrfs_unlink_inode(trans, root, old_dir, 9825 d_inode(old_dentry), 9826 old_dentry->d_name.name, 9827 old_dentry->d_name.len); 9828 if (!ret) 9829 ret = btrfs_update_inode(trans, root, old_inode); 9830 } 9831 if (ret) { 9832 btrfs_abort_transaction(trans, root, ret); 9833 goto out_fail; 9834 } 9835 9836 if (new_inode) { 9837 inode_inc_iversion(new_inode); 9838 new_inode->i_ctime = current_fs_time(new_inode->i_sb); 9839 if (unlikely(btrfs_ino(new_inode) == 9840 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { 9841 root_objectid = BTRFS_I(new_inode)->location.objectid; 9842 ret = btrfs_unlink_subvol(trans, dest, new_dir, 9843 root_objectid, 9844 new_dentry->d_name.name, 9845 new_dentry->d_name.len); 9846 BUG_ON(new_inode->i_nlink == 0); 9847 } else { 9848 ret = btrfs_unlink_inode(trans, dest, new_dir, 9849 d_inode(new_dentry), 9850 new_dentry->d_name.name, 9851 new_dentry->d_name.len); 9852 } 9853 if (!ret && new_inode->i_nlink == 0) 9854 ret = btrfs_orphan_add(trans, d_inode(new_dentry)); 9855 if (ret) { 9856 btrfs_abort_transaction(trans, root, ret); 9857 goto out_fail; 9858 } 9859 } 9860 9861 ret = btrfs_add_link(trans, new_dir, old_inode, 9862 new_dentry->d_name.name, 9863 new_dentry->d_name.len, 0, index); 9864 if (ret) { 9865 btrfs_abort_transaction(trans, root, ret); 9866 goto out_fail; 9867 } 9868 9869 if (old_inode->i_nlink == 1) 9870 BTRFS_I(old_inode)->dir_index = index; 9871 9872 if (log_pinned) { 9873 struct dentry *parent = new_dentry->d_parent; 9874 9875 btrfs_log_new_name(trans, old_inode, old_dir, parent); 9876 btrfs_end_log_trans(root); 9877 log_pinned = false; 9878 } 9879 9880 if (flags & RENAME_WHITEOUT) { 9881 ret = btrfs_whiteout_for_rename(trans, root, old_dir, 9882 old_dentry); 9883 9884 if (ret) { 9885 btrfs_abort_transaction(trans, root, ret); 9886 goto out_fail; 9887 } 9888 } 9889 out_fail: 9890 /* 9891 * If we have pinned the log and an error happened, we unpin tasks 9892 * trying to sync the log and force them to fallback to a transaction 9893 * commit if the log currently contains any of the inodes involved in 9894 * this rename operation (to ensure we do not persist a log with an 9895 * inconsistent state for any of these inodes or leading to any 9896 * inconsistencies when replayed). If the transaction was aborted, the 9897 * abortion reason is propagated to userspace when attempting to commit 9898 * the transaction. If the log does not contain any of these inodes, we 9899 * allow the tasks to sync it. 9900 */ 9901 if (ret && log_pinned) { 9902 if (btrfs_inode_in_log(old_dir, root->fs_info->generation) || 9903 btrfs_inode_in_log(new_dir, root->fs_info->generation) || 9904 btrfs_inode_in_log(old_inode, root->fs_info->generation) || 9905 (new_inode && 9906 btrfs_inode_in_log(new_inode, root->fs_info->generation))) 9907 btrfs_set_log_full_commit(root->fs_info, trans); 9908 9909 btrfs_end_log_trans(root); 9910 log_pinned = false; 9911 } 9912 btrfs_end_transaction(trans, root); 9913 out_notrans: 9914 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9915 up_read(&root->fs_info->subvol_sem); 9916 9917 return ret; 9918 } 9919 9920 static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry, 9921 struct inode *new_dir, struct dentry *new_dentry, 9922 unsigned int flags) 9923 { 9924 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 9925 return -EINVAL; 9926 9927 if (flags & RENAME_EXCHANGE) 9928 return btrfs_rename_exchange(old_dir, old_dentry, new_dir, 9929 new_dentry); 9930 9931 return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 9932 } 9933 9934 static void btrfs_run_delalloc_work(struct btrfs_work *work) 9935 { 9936 struct btrfs_delalloc_work *delalloc_work; 9937 struct inode *inode; 9938 9939 delalloc_work = container_of(work, struct btrfs_delalloc_work, 9940 work); 9941 inode = delalloc_work->inode; 9942 filemap_flush(inode->i_mapping); 9943 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 9944 &BTRFS_I(inode)->runtime_flags)) 9945 filemap_flush(inode->i_mapping); 9946 9947 if (delalloc_work->delay_iput) 9948 btrfs_add_delayed_iput(inode); 9949 else 9950 iput(inode); 9951 complete(&delalloc_work->completion); 9952 } 9953 9954 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode, 9955 int delay_iput) 9956 { 9957 struct btrfs_delalloc_work *work; 9958 9959 work = kmalloc(sizeof(*work), GFP_NOFS); 9960 if (!work) 9961 return NULL; 9962 9963 init_completion(&work->completion); 9964 INIT_LIST_HEAD(&work->list); 9965 work->inode = inode; 9966 work->delay_iput = delay_iput; 9967 WARN_ON_ONCE(!inode); 9968 btrfs_init_work(&work->work, btrfs_flush_delalloc_helper, 9969 btrfs_run_delalloc_work, NULL, NULL); 9970 9971 return work; 9972 } 9973 9974 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work) 9975 { 9976 wait_for_completion(&work->completion); 9977 kfree(work); 9978 } 9979 9980 /* 9981 * some fairly slow code that needs optimization. This walks the list 9982 * of all the inodes with pending delalloc and forces them to disk. 9983 */ 9984 static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput, 9985 int nr) 9986 { 9987 struct btrfs_inode *binode; 9988 struct inode *inode; 9989 struct btrfs_delalloc_work *work, *next; 9990 struct list_head works; 9991 struct list_head splice; 9992 int ret = 0; 9993 9994 INIT_LIST_HEAD(&works); 9995 INIT_LIST_HEAD(&splice); 9996 9997 mutex_lock(&root->delalloc_mutex); 9998 spin_lock(&root->delalloc_lock); 9999 list_splice_init(&root->delalloc_inodes, &splice); 10000 while (!list_empty(&splice)) { 10001 binode = list_entry(splice.next, struct btrfs_inode, 10002 delalloc_inodes); 10003 10004 list_move_tail(&binode->delalloc_inodes, 10005 &root->delalloc_inodes); 10006 inode = igrab(&binode->vfs_inode); 10007 if (!inode) { 10008 cond_resched_lock(&root->delalloc_lock); 10009 continue; 10010 } 10011 spin_unlock(&root->delalloc_lock); 10012 10013 work = btrfs_alloc_delalloc_work(inode, delay_iput); 10014 if (!work) { 10015 if (delay_iput) 10016 btrfs_add_delayed_iput(inode); 10017 else 10018 iput(inode); 10019 ret = -ENOMEM; 10020 goto out; 10021 } 10022 list_add_tail(&work->list, &works); 10023 btrfs_queue_work(root->fs_info->flush_workers, 10024 &work->work); 10025 ret++; 10026 if (nr != -1 && ret >= nr) 10027 goto out; 10028 cond_resched(); 10029 spin_lock(&root->delalloc_lock); 10030 } 10031 spin_unlock(&root->delalloc_lock); 10032 10033 out: 10034 list_for_each_entry_safe(work, next, &works, list) { 10035 list_del_init(&work->list); 10036 btrfs_wait_and_free_delalloc_work(work); 10037 } 10038 10039 if (!list_empty_careful(&splice)) { 10040 spin_lock(&root->delalloc_lock); 10041 list_splice_tail(&splice, &root->delalloc_inodes); 10042 spin_unlock(&root->delalloc_lock); 10043 } 10044 mutex_unlock(&root->delalloc_mutex); 10045 return ret; 10046 } 10047 10048 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput) 10049 { 10050 int ret; 10051 10052 if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) 10053 return -EROFS; 10054 10055 ret = __start_delalloc_inodes(root, delay_iput, -1); 10056 if (ret > 0) 10057 ret = 0; 10058 /* 10059 * the filemap_flush will queue IO into the worker threads, but 10060 * we have to make sure the IO is actually started and that 10061 * ordered extents get created before we return 10062 */ 10063 atomic_inc(&root->fs_info->async_submit_draining); 10064 while (atomic_read(&root->fs_info->nr_async_submits) || 10065 atomic_read(&root->fs_info->async_delalloc_pages)) { 10066 wait_event(root->fs_info->async_submit_wait, 10067 (atomic_read(&root->fs_info->nr_async_submits) == 0 && 10068 atomic_read(&root->fs_info->async_delalloc_pages) == 0)); 10069 } 10070 atomic_dec(&root->fs_info->async_submit_draining); 10071 return ret; 10072 } 10073 10074 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int delay_iput, 10075 int nr) 10076 { 10077 struct btrfs_root *root; 10078 struct list_head splice; 10079 int ret; 10080 10081 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 10082 return -EROFS; 10083 10084 INIT_LIST_HEAD(&splice); 10085 10086 mutex_lock(&fs_info->delalloc_root_mutex); 10087 spin_lock(&fs_info->delalloc_root_lock); 10088 list_splice_init(&fs_info->delalloc_roots, &splice); 10089 while (!list_empty(&splice) && nr) { 10090 root = list_first_entry(&splice, struct btrfs_root, 10091 delalloc_root); 10092 root = btrfs_grab_fs_root(root); 10093 BUG_ON(!root); 10094 list_move_tail(&root->delalloc_root, 10095 &fs_info->delalloc_roots); 10096 spin_unlock(&fs_info->delalloc_root_lock); 10097 10098 ret = __start_delalloc_inodes(root, delay_iput, nr); 10099 btrfs_put_fs_root(root); 10100 if (ret < 0) 10101 goto out; 10102 10103 if (nr != -1) { 10104 nr -= ret; 10105 WARN_ON(nr < 0); 10106 } 10107 spin_lock(&fs_info->delalloc_root_lock); 10108 } 10109 spin_unlock(&fs_info->delalloc_root_lock); 10110 10111 ret = 0; 10112 atomic_inc(&fs_info->async_submit_draining); 10113 while (atomic_read(&fs_info->nr_async_submits) || 10114 atomic_read(&fs_info->async_delalloc_pages)) { 10115 wait_event(fs_info->async_submit_wait, 10116 (atomic_read(&fs_info->nr_async_submits) == 0 && 10117 atomic_read(&fs_info->async_delalloc_pages) == 0)); 10118 } 10119 atomic_dec(&fs_info->async_submit_draining); 10120 out: 10121 if (!list_empty_careful(&splice)) { 10122 spin_lock(&fs_info->delalloc_root_lock); 10123 list_splice_tail(&splice, &fs_info->delalloc_roots); 10124 spin_unlock(&fs_info->delalloc_root_lock); 10125 } 10126 mutex_unlock(&fs_info->delalloc_root_mutex); 10127 return ret; 10128 } 10129 10130 static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 10131 const char *symname) 10132 { 10133 struct btrfs_trans_handle *trans; 10134 struct btrfs_root *root = BTRFS_I(dir)->root; 10135 struct btrfs_path *path; 10136 struct btrfs_key key; 10137 struct inode *inode = NULL; 10138 int err; 10139 int drop_inode = 0; 10140 u64 objectid; 10141 u64 index = 0; 10142 int name_len; 10143 int datasize; 10144 unsigned long ptr; 10145 struct btrfs_file_extent_item *ei; 10146 struct extent_buffer *leaf; 10147 10148 name_len = strlen(symname); 10149 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root)) 10150 return -ENAMETOOLONG; 10151 10152 /* 10153 * 2 items for inode item and ref 10154 * 2 items for dir items 10155 * 1 item for updating parent inode item 10156 * 1 item for the inline extent item 10157 * 1 item for xattr if selinux is on 10158 */ 10159 trans = btrfs_start_transaction(root, 7); 10160 if (IS_ERR(trans)) 10161 return PTR_ERR(trans); 10162 10163 err = btrfs_find_free_ino(root, &objectid); 10164 if (err) 10165 goto out_unlock; 10166 10167 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 10168 dentry->d_name.len, btrfs_ino(dir), objectid, 10169 S_IFLNK|S_IRWXUGO, &index); 10170 if (IS_ERR(inode)) { 10171 err = PTR_ERR(inode); 10172 goto out_unlock; 10173 } 10174 10175 /* 10176 * If the active LSM wants to access the inode during 10177 * d_instantiate it needs these. Smack checks to see 10178 * if the filesystem supports xattrs by looking at the 10179 * ops vector. 10180 */ 10181 inode->i_fop = &btrfs_file_operations; 10182 inode->i_op = &btrfs_file_inode_operations; 10183 inode->i_mapping->a_ops = &btrfs_aops; 10184 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 10185 10186 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 10187 if (err) 10188 goto out_unlock_inode; 10189 10190 path = btrfs_alloc_path(); 10191 if (!path) { 10192 err = -ENOMEM; 10193 goto out_unlock_inode; 10194 } 10195 key.objectid = btrfs_ino(inode); 10196 key.offset = 0; 10197 key.type = BTRFS_EXTENT_DATA_KEY; 10198 datasize = btrfs_file_extent_calc_inline_size(name_len); 10199 err = btrfs_insert_empty_item(trans, root, path, &key, 10200 datasize); 10201 if (err) { 10202 btrfs_free_path(path); 10203 goto out_unlock_inode; 10204 } 10205 leaf = path->nodes[0]; 10206 ei = btrfs_item_ptr(leaf, path->slots[0], 10207 struct btrfs_file_extent_item); 10208 btrfs_set_file_extent_generation(leaf, ei, trans->transid); 10209 btrfs_set_file_extent_type(leaf, ei, 10210 BTRFS_FILE_EXTENT_INLINE); 10211 btrfs_set_file_extent_encryption(leaf, ei, 0); 10212 btrfs_set_file_extent_compression(leaf, ei, 0); 10213 btrfs_set_file_extent_other_encoding(leaf, ei, 0); 10214 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); 10215 10216 ptr = btrfs_file_extent_inline_start(ei); 10217 write_extent_buffer(leaf, symname, ptr, name_len); 10218 btrfs_mark_buffer_dirty(leaf); 10219 btrfs_free_path(path); 10220 10221 inode->i_op = &btrfs_symlink_inode_operations; 10222 inode_nohighmem(inode); 10223 inode->i_mapping->a_ops = &btrfs_symlink_aops; 10224 inode_set_bytes(inode, name_len); 10225 btrfs_i_size_write(inode, name_len); 10226 err = btrfs_update_inode(trans, root, inode); 10227 /* 10228 * Last step, add directory indexes for our symlink inode. This is the 10229 * last step to avoid extra cleanup of these indexes if an error happens 10230 * elsewhere above. 10231 */ 10232 if (!err) 10233 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); 10234 if (err) { 10235 drop_inode = 1; 10236 goto out_unlock_inode; 10237 } 10238 10239 unlock_new_inode(inode); 10240 d_instantiate(dentry, inode); 10241 10242 out_unlock: 10243 btrfs_end_transaction(trans, root); 10244 if (drop_inode) { 10245 inode_dec_link_count(inode); 10246 iput(inode); 10247 } 10248 btrfs_btree_balance_dirty(root); 10249 return err; 10250 10251 out_unlock_inode: 10252 drop_inode = 1; 10253 unlock_new_inode(inode); 10254 goto out_unlock; 10255 } 10256 10257 static int __btrfs_prealloc_file_range(struct inode *inode, int mode, 10258 u64 start, u64 num_bytes, u64 min_size, 10259 loff_t actual_len, u64 *alloc_hint, 10260 struct btrfs_trans_handle *trans) 10261 { 10262 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 10263 struct extent_map *em; 10264 struct btrfs_root *root = BTRFS_I(inode)->root; 10265 struct btrfs_key ins; 10266 u64 cur_offset = start; 10267 u64 i_size; 10268 u64 cur_bytes; 10269 u64 last_alloc = (u64)-1; 10270 int ret = 0; 10271 bool own_trans = true; 10272 10273 if (trans) 10274 own_trans = false; 10275 while (num_bytes > 0) { 10276 if (own_trans) { 10277 trans = btrfs_start_transaction(root, 3); 10278 if (IS_ERR(trans)) { 10279 ret = PTR_ERR(trans); 10280 break; 10281 } 10282 } 10283 10284 cur_bytes = min_t(u64, num_bytes, SZ_256M); 10285 cur_bytes = max(cur_bytes, min_size); 10286 /* 10287 * If we are severely fragmented we could end up with really 10288 * small allocations, so if the allocator is returning small 10289 * chunks lets make its job easier by only searching for those 10290 * sized chunks. 10291 */ 10292 cur_bytes = min(cur_bytes, last_alloc); 10293 ret = btrfs_reserve_extent(root, cur_bytes, min_size, 0, 10294 *alloc_hint, &ins, 1, 0); 10295 if (ret) { 10296 if (own_trans) 10297 btrfs_end_transaction(trans, root); 10298 break; 10299 } 10300 btrfs_dec_block_group_reservations(root->fs_info, ins.objectid); 10301 10302 last_alloc = ins.offset; 10303 ret = insert_reserved_file_extent(trans, inode, 10304 cur_offset, ins.objectid, 10305 ins.offset, ins.offset, 10306 ins.offset, 0, 0, 0, 10307 BTRFS_FILE_EXTENT_PREALLOC); 10308 if (ret) { 10309 btrfs_free_reserved_extent(root, ins.objectid, 10310 ins.offset, 0); 10311 btrfs_abort_transaction(trans, root, ret); 10312 if (own_trans) 10313 btrfs_end_transaction(trans, root); 10314 break; 10315 } 10316 10317 btrfs_drop_extent_cache(inode, cur_offset, 10318 cur_offset + ins.offset -1, 0); 10319 10320 em = alloc_extent_map(); 10321 if (!em) { 10322 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 10323 &BTRFS_I(inode)->runtime_flags); 10324 goto next; 10325 } 10326 10327 em->start = cur_offset; 10328 em->orig_start = cur_offset; 10329 em->len = ins.offset; 10330 em->block_start = ins.objectid; 10331 em->block_len = ins.offset; 10332 em->orig_block_len = ins.offset; 10333 em->ram_bytes = ins.offset; 10334 em->bdev = root->fs_info->fs_devices->latest_bdev; 10335 set_bit(EXTENT_FLAG_PREALLOC, &em->flags); 10336 em->generation = trans->transid; 10337 10338 while (1) { 10339 write_lock(&em_tree->lock); 10340 ret = add_extent_mapping(em_tree, em, 1); 10341 write_unlock(&em_tree->lock); 10342 if (ret != -EEXIST) 10343 break; 10344 btrfs_drop_extent_cache(inode, cur_offset, 10345 cur_offset + ins.offset - 1, 10346 0); 10347 } 10348 free_extent_map(em); 10349 next: 10350 num_bytes -= ins.offset; 10351 cur_offset += ins.offset; 10352 *alloc_hint = ins.objectid + ins.offset; 10353 10354 inode_inc_iversion(inode); 10355 inode->i_ctime = current_fs_time(inode->i_sb); 10356 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC; 10357 if (!(mode & FALLOC_FL_KEEP_SIZE) && 10358 (actual_len > inode->i_size) && 10359 (cur_offset > inode->i_size)) { 10360 if (cur_offset > actual_len) 10361 i_size = actual_len; 10362 else 10363 i_size = cur_offset; 10364 i_size_write(inode, i_size); 10365 btrfs_ordered_update_i_size(inode, i_size, NULL); 10366 } 10367 10368 ret = btrfs_update_inode(trans, root, inode); 10369 10370 if (ret) { 10371 btrfs_abort_transaction(trans, root, ret); 10372 if (own_trans) 10373 btrfs_end_transaction(trans, root); 10374 break; 10375 } 10376 10377 if (own_trans) 10378 btrfs_end_transaction(trans, root); 10379 } 10380 return ret; 10381 } 10382 10383 int btrfs_prealloc_file_range(struct inode *inode, int mode, 10384 u64 start, u64 num_bytes, u64 min_size, 10385 loff_t actual_len, u64 *alloc_hint) 10386 { 10387 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, 10388 min_size, actual_len, alloc_hint, 10389 NULL); 10390 } 10391 10392 int btrfs_prealloc_file_range_trans(struct inode *inode, 10393 struct btrfs_trans_handle *trans, int mode, 10394 u64 start, u64 num_bytes, u64 min_size, 10395 loff_t actual_len, u64 *alloc_hint) 10396 { 10397 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, 10398 min_size, actual_len, alloc_hint, trans); 10399 } 10400 10401 static int btrfs_set_page_dirty(struct page *page) 10402 { 10403 return __set_page_dirty_nobuffers(page); 10404 } 10405 10406 static int btrfs_permission(struct inode *inode, int mask) 10407 { 10408 struct btrfs_root *root = BTRFS_I(inode)->root; 10409 umode_t mode = inode->i_mode; 10410 10411 if (mask & MAY_WRITE && 10412 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) { 10413 if (btrfs_root_readonly(root)) 10414 return -EROFS; 10415 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) 10416 return -EACCES; 10417 } 10418 return generic_permission(inode, mask); 10419 } 10420 10421 static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 10422 { 10423 struct btrfs_trans_handle *trans; 10424 struct btrfs_root *root = BTRFS_I(dir)->root; 10425 struct inode *inode = NULL; 10426 u64 objectid; 10427 u64 index; 10428 int ret = 0; 10429 10430 /* 10431 * 5 units required for adding orphan entry 10432 */ 10433 trans = btrfs_start_transaction(root, 5); 10434 if (IS_ERR(trans)) 10435 return PTR_ERR(trans); 10436 10437 ret = btrfs_find_free_ino(root, &objectid); 10438 if (ret) 10439 goto out; 10440 10441 inode = btrfs_new_inode(trans, root, dir, NULL, 0, 10442 btrfs_ino(dir), objectid, mode, &index); 10443 if (IS_ERR(inode)) { 10444 ret = PTR_ERR(inode); 10445 inode = NULL; 10446 goto out; 10447 } 10448 10449 inode->i_fop = &btrfs_file_operations; 10450 inode->i_op = &btrfs_file_inode_operations; 10451 10452 inode->i_mapping->a_ops = &btrfs_aops; 10453 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 10454 10455 ret = btrfs_init_inode_security(trans, inode, dir, NULL); 10456 if (ret) 10457 goto out_inode; 10458 10459 ret = btrfs_update_inode(trans, root, inode); 10460 if (ret) 10461 goto out_inode; 10462 ret = btrfs_orphan_add(trans, inode); 10463 if (ret) 10464 goto out_inode; 10465 10466 /* 10467 * We set number of links to 0 in btrfs_new_inode(), and here we set 10468 * it to 1 because d_tmpfile() will issue a warning if the count is 0, 10469 * through: 10470 * 10471 * d_tmpfile() -> inode_dec_link_count() -> drop_nlink() 10472 */ 10473 set_nlink(inode, 1); 10474 unlock_new_inode(inode); 10475 d_tmpfile(dentry, inode); 10476 mark_inode_dirty(inode); 10477 10478 out: 10479 btrfs_end_transaction(trans, root); 10480 if (ret) 10481 iput(inode); 10482 btrfs_balance_delayed_items(root); 10483 btrfs_btree_balance_dirty(root); 10484 return ret; 10485 10486 out_inode: 10487 unlock_new_inode(inode); 10488 goto out; 10489 10490 } 10491 10492 /* Inspired by filemap_check_errors() */ 10493 int btrfs_inode_check_errors(struct inode *inode) 10494 { 10495 int ret = 0; 10496 10497 if (test_bit(AS_ENOSPC, &inode->i_mapping->flags) && 10498 test_and_clear_bit(AS_ENOSPC, &inode->i_mapping->flags)) 10499 ret = -ENOSPC; 10500 if (test_bit(AS_EIO, &inode->i_mapping->flags) && 10501 test_and_clear_bit(AS_EIO, &inode->i_mapping->flags)) 10502 ret = -EIO; 10503 10504 return ret; 10505 } 10506 10507 static const struct inode_operations btrfs_dir_inode_operations = { 10508 .getattr = btrfs_getattr, 10509 .lookup = btrfs_lookup, 10510 .create = btrfs_create, 10511 .unlink = btrfs_unlink, 10512 .link = btrfs_link, 10513 .mkdir = btrfs_mkdir, 10514 .rmdir = btrfs_rmdir, 10515 .rename2 = btrfs_rename2, 10516 .symlink = btrfs_symlink, 10517 .setattr = btrfs_setattr, 10518 .mknod = btrfs_mknod, 10519 .setxattr = generic_setxattr, 10520 .getxattr = generic_getxattr, 10521 .listxattr = btrfs_listxattr, 10522 .removexattr = generic_removexattr, 10523 .permission = btrfs_permission, 10524 .get_acl = btrfs_get_acl, 10525 .set_acl = btrfs_set_acl, 10526 .update_time = btrfs_update_time, 10527 .tmpfile = btrfs_tmpfile, 10528 }; 10529 static const struct inode_operations btrfs_dir_ro_inode_operations = { 10530 .lookup = btrfs_lookup, 10531 .permission = btrfs_permission, 10532 .get_acl = btrfs_get_acl, 10533 .set_acl = btrfs_set_acl, 10534 .update_time = btrfs_update_time, 10535 }; 10536 10537 static const struct file_operations btrfs_dir_file_operations = { 10538 .llseek = generic_file_llseek, 10539 .read = generic_read_dir, 10540 .iterate_shared = btrfs_real_readdir, 10541 .unlocked_ioctl = btrfs_ioctl, 10542 #ifdef CONFIG_COMPAT 10543 .compat_ioctl = btrfs_compat_ioctl, 10544 #endif 10545 .release = btrfs_release_file, 10546 .fsync = btrfs_sync_file, 10547 }; 10548 10549 static const struct extent_io_ops btrfs_extent_io_ops = { 10550 .fill_delalloc = run_delalloc_range, 10551 .submit_bio_hook = btrfs_submit_bio_hook, 10552 .merge_bio_hook = btrfs_merge_bio_hook, 10553 .readpage_end_io_hook = btrfs_readpage_end_io_hook, 10554 .writepage_end_io_hook = btrfs_writepage_end_io_hook, 10555 .writepage_start_hook = btrfs_writepage_start_hook, 10556 .set_bit_hook = btrfs_set_bit_hook, 10557 .clear_bit_hook = btrfs_clear_bit_hook, 10558 .merge_extent_hook = btrfs_merge_extent_hook, 10559 .split_extent_hook = btrfs_split_extent_hook, 10560 }; 10561 10562 /* 10563 * btrfs doesn't support the bmap operation because swapfiles 10564 * use bmap to make a mapping of extents in the file. They assume 10565 * these extents won't change over the life of the file and they 10566 * use the bmap result to do IO directly to the drive. 10567 * 10568 * the btrfs bmap call would return logical addresses that aren't 10569 * suitable for IO and they also will change frequently as COW 10570 * operations happen. So, swapfile + btrfs == corruption. 10571 * 10572 * For now we're avoiding this by dropping bmap. 10573 */ 10574 static const struct address_space_operations btrfs_aops = { 10575 .readpage = btrfs_readpage, 10576 .writepage = btrfs_writepage, 10577 .writepages = btrfs_writepages, 10578 .readpages = btrfs_readpages, 10579 .direct_IO = btrfs_direct_IO, 10580 .invalidatepage = btrfs_invalidatepage, 10581 .releasepage = btrfs_releasepage, 10582 .set_page_dirty = btrfs_set_page_dirty, 10583 .error_remove_page = generic_error_remove_page, 10584 }; 10585 10586 static const struct address_space_operations btrfs_symlink_aops = { 10587 .readpage = btrfs_readpage, 10588 .writepage = btrfs_writepage, 10589 .invalidatepage = btrfs_invalidatepage, 10590 .releasepage = btrfs_releasepage, 10591 }; 10592 10593 static const struct inode_operations btrfs_file_inode_operations = { 10594 .getattr = btrfs_getattr, 10595 .setattr = btrfs_setattr, 10596 .setxattr = generic_setxattr, 10597 .getxattr = generic_getxattr, 10598 .listxattr = btrfs_listxattr, 10599 .removexattr = generic_removexattr, 10600 .permission = btrfs_permission, 10601 .fiemap = btrfs_fiemap, 10602 .get_acl = btrfs_get_acl, 10603 .set_acl = btrfs_set_acl, 10604 .update_time = btrfs_update_time, 10605 }; 10606 static const struct inode_operations btrfs_special_inode_operations = { 10607 .getattr = btrfs_getattr, 10608 .setattr = btrfs_setattr, 10609 .permission = btrfs_permission, 10610 .setxattr = generic_setxattr, 10611 .getxattr = generic_getxattr, 10612 .listxattr = btrfs_listxattr, 10613 .removexattr = generic_removexattr, 10614 .get_acl = btrfs_get_acl, 10615 .set_acl = btrfs_set_acl, 10616 .update_time = btrfs_update_time, 10617 }; 10618 static const struct inode_operations btrfs_symlink_inode_operations = { 10619 .readlink = generic_readlink, 10620 .get_link = page_get_link, 10621 .getattr = btrfs_getattr, 10622 .setattr = btrfs_setattr, 10623 .permission = btrfs_permission, 10624 .setxattr = generic_setxattr, 10625 .getxattr = generic_getxattr, 10626 .listxattr = btrfs_listxattr, 10627 .removexattr = generic_removexattr, 10628 .update_time = btrfs_update_time, 10629 }; 10630 10631 const struct dentry_operations btrfs_dentry_operations = { 10632 .d_delete = btrfs_dentry_delete, 10633 .d_release = btrfs_dentry_release, 10634 }; 10635