1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2007 Oracle. All rights reserved. 4 */ 5 6 #include <linux/kernel.h> 7 #include <linux/bio.h> 8 #include <linux/buffer_head.h> 9 #include <linux/file.h> 10 #include <linux/fs.h> 11 #include <linux/pagemap.h> 12 #include <linux/highmem.h> 13 #include <linux/time.h> 14 #include <linux/init.h> 15 #include <linux/string.h> 16 #include <linux/backing-dev.h> 17 #include <linux/writeback.h> 18 #include <linux/compat.h> 19 #include <linux/xattr.h> 20 #include <linux/posix_acl.h> 21 #include <linux/falloc.h> 22 #include <linux/slab.h> 23 #include <linux/ratelimit.h> 24 #include <linux/btrfs.h> 25 #include <linux/blkdev.h> 26 #include <linux/posix_acl_xattr.h> 27 #include <linux/uio.h> 28 #include <linux/magic.h> 29 #include <linux/iversion.h> 30 #include <asm/unaligned.h> 31 #include "ctree.h" 32 #include "disk-io.h" 33 #include "transaction.h" 34 #include "btrfs_inode.h" 35 #include "print-tree.h" 36 #include "ordered-data.h" 37 #include "xattr.h" 38 #include "tree-log.h" 39 #include "volumes.h" 40 #include "compression.h" 41 #include "locking.h" 42 #include "free-space-cache.h" 43 #include "inode-map.h" 44 #include "backref.h" 45 #include "props.h" 46 #include "qgroup.h" 47 #include "dedupe.h" 48 49 struct btrfs_iget_args { 50 struct btrfs_key *location; 51 struct btrfs_root *root; 52 }; 53 54 struct btrfs_dio_data { 55 u64 reserve; 56 u64 unsubmitted_oe_range_start; 57 u64 unsubmitted_oe_range_end; 58 int overwrite; 59 }; 60 61 static const struct inode_operations btrfs_dir_inode_operations; 62 static const struct inode_operations btrfs_symlink_inode_operations; 63 static const struct inode_operations btrfs_dir_ro_inode_operations; 64 static const struct inode_operations btrfs_special_inode_operations; 65 static const struct inode_operations btrfs_file_inode_operations; 66 static const struct address_space_operations btrfs_aops; 67 static const struct address_space_operations btrfs_symlink_aops; 68 static const struct file_operations btrfs_dir_file_operations; 69 static const struct extent_io_ops btrfs_extent_io_ops; 70 71 static struct kmem_cache *btrfs_inode_cachep; 72 struct kmem_cache *btrfs_trans_handle_cachep; 73 struct kmem_cache *btrfs_path_cachep; 74 struct kmem_cache *btrfs_free_space_cachep; 75 76 #define S_SHIFT 12 77 static const unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = { 78 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE, 79 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR, 80 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV, 81 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV, 82 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO, 83 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK, 84 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK, 85 }; 86 87 static int btrfs_setsize(struct inode *inode, struct iattr *attr); 88 static int btrfs_truncate(struct inode *inode, bool skip_writeback); 89 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent); 90 static noinline int cow_file_range(struct inode *inode, 91 struct page *locked_page, 92 u64 start, u64 end, u64 delalloc_end, 93 int *page_started, unsigned long *nr_written, 94 int unlock, struct btrfs_dedupe_hash *hash); 95 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len, 96 u64 orig_start, u64 block_start, 97 u64 block_len, u64 orig_block_len, 98 u64 ram_bytes, int compress_type, 99 int type); 100 101 static void __endio_write_update_ordered(struct inode *inode, 102 const u64 offset, const u64 bytes, 103 const bool uptodate); 104 105 /* 106 * Cleanup all submitted ordered extents in specified range to handle errors 107 * from the fill_dellaloc() callback. 108 * 109 * NOTE: caller must ensure that when an error happens, it can not call 110 * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING 111 * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata 112 * to be released, which we want to happen only when finishing the ordered 113 * extent (btrfs_finish_ordered_io()). Also note that the caller of the 114 * fill_delalloc() callback already does proper cleanup for the first page of 115 * the range, that is, it invokes the callback writepage_end_io_hook() for the 116 * range of the first page. 117 */ 118 static inline void btrfs_cleanup_ordered_extents(struct inode *inode, 119 const u64 offset, 120 const u64 bytes) 121 { 122 unsigned long index = offset >> PAGE_SHIFT; 123 unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT; 124 struct page *page; 125 126 while (index <= end_index) { 127 page = find_get_page(inode->i_mapping, index); 128 index++; 129 if (!page) 130 continue; 131 ClearPagePrivate2(page); 132 put_page(page); 133 } 134 return __endio_write_update_ordered(inode, offset + PAGE_SIZE, 135 bytes - PAGE_SIZE, false); 136 } 137 138 static int btrfs_dirty_inode(struct inode *inode); 139 140 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 141 void btrfs_test_inode_set_ops(struct inode *inode) 142 { 143 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 144 } 145 #endif 146 147 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, 148 struct inode *inode, struct inode *dir, 149 const struct qstr *qstr) 150 { 151 int err; 152 153 err = btrfs_init_acl(trans, inode, dir); 154 if (!err) 155 err = btrfs_xattr_security_init(trans, inode, dir, qstr); 156 return err; 157 } 158 159 /* 160 * this does all the hard work for inserting an inline extent into 161 * the btree. The caller should have done a btrfs_drop_extents so that 162 * no overlapping inline items exist in the btree 163 */ 164 static int insert_inline_extent(struct btrfs_trans_handle *trans, 165 struct btrfs_path *path, int extent_inserted, 166 struct btrfs_root *root, struct inode *inode, 167 u64 start, size_t size, size_t compressed_size, 168 int compress_type, 169 struct page **compressed_pages) 170 { 171 struct extent_buffer *leaf; 172 struct page *page = NULL; 173 char *kaddr; 174 unsigned long ptr; 175 struct btrfs_file_extent_item *ei; 176 int ret; 177 size_t cur_size = size; 178 unsigned long offset; 179 180 if (compressed_size && compressed_pages) 181 cur_size = compressed_size; 182 183 inode_add_bytes(inode, size); 184 185 if (!extent_inserted) { 186 struct btrfs_key key; 187 size_t datasize; 188 189 key.objectid = btrfs_ino(BTRFS_I(inode)); 190 key.offset = start; 191 key.type = BTRFS_EXTENT_DATA_KEY; 192 193 datasize = btrfs_file_extent_calc_inline_size(cur_size); 194 path->leave_spinning = 1; 195 ret = btrfs_insert_empty_item(trans, root, path, &key, 196 datasize); 197 if (ret) 198 goto fail; 199 } 200 leaf = path->nodes[0]; 201 ei = btrfs_item_ptr(leaf, path->slots[0], 202 struct btrfs_file_extent_item); 203 btrfs_set_file_extent_generation(leaf, ei, trans->transid); 204 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); 205 btrfs_set_file_extent_encryption(leaf, ei, 0); 206 btrfs_set_file_extent_other_encoding(leaf, ei, 0); 207 btrfs_set_file_extent_ram_bytes(leaf, ei, size); 208 ptr = btrfs_file_extent_inline_start(ei); 209 210 if (compress_type != BTRFS_COMPRESS_NONE) { 211 struct page *cpage; 212 int i = 0; 213 while (compressed_size > 0) { 214 cpage = compressed_pages[i]; 215 cur_size = min_t(unsigned long, compressed_size, 216 PAGE_SIZE); 217 218 kaddr = kmap_atomic(cpage); 219 write_extent_buffer(leaf, kaddr, ptr, cur_size); 220 kunmap_atomic(kaddr); 221 222 i++; 223 ptr += cur_size; 224 compressed_size -= cur_size; 225 } 226 btrfs_set_file_extent_compression(leaf, ei, 227 compress_type); 228 } else { 229 page = find_get_page(inode->i_mapping, 230 start >> PAGE_SHIFT); 231 btrfs_set_file_extent_compression(leaf, ei, 0); 232 kaddr = kmap_atomic(page); 233 offset = start & (PAGE_SIZE - 1); 234 write_extent_buffer(leaf, kaddr + offset, ptr, size); 235 kunmap_atomic(kaddr); 236 put_page(page); 237 } 238 btrfs_mark_buffer_dirty(leaf); 239 btrfs_release_path(path); 240 241 /* 242 * we're an inline extent, so nobody can 243 * extend the file past i_size without locking 244 * a page we already have locked. 245 * 246 * We must do any isize and inode updates 247 * before we unlock the pages. Otherwise we 248 * could end up racing with unlink. 249 */ 250 BTRFS_I(inode)->disk_i_size = inode->i_size; 251 ret = btrfs_update_inode(trans, root, inode); 252 253 fail: 254 return ret; 255 } 256 257 258 /* 259 * conditionally insert an inline extent into the file. This 260 * does the checks required to make sure the data is small enough 261 * to fit as an inline extent. 262 */ 263 static noinline int cow_file_range_inline(struct inode *inode, u64 start, 264 u64 end, size_t compressed_size, 265 int compress_type, 266 struct page **compressed_pages) 267 { 268 struct btrfs_root *root = BTRFS_I(inode)->root; 269 struct btrfs_fs_info *fs_info = root->fs_info; 270 struct btrfs_trans_handle *trans; 271 u64 isize = i_size_read(inode); 272 u64 actual_end = min(end + 1, isize); 273 u64 inline_len = actual_end - start; 274 u64 aligned_end = ALIGN(end, fs_info->sectorsize); 275 u64 data_len = inline_len; 276 int ret; 277 struct btrfs_path *path; 278 int extent_inserted = 0; 279 u32 extent_item_size; 280 281 if (compressed_size) 282 data_len = compressed_size; 283 284 if (start > 0 || 285 actual_end > fs_info->sectorsize || 286 data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) || 287 (!compressed_size && 288 (actual_end & (fs_info->sectorsize - 1)) == 0) || 289 end + 1 < isize || 290 data_len > fs_info->max_inline) { 291 return 1; 292 } 293 294 path = btrfs_alloc_path(); 295 if (!path) 296 return -ENOMEM; 297 298 trans = btrfs_join_transaction(root); 299 if (IS_ERR(trans)) { 300 btrfs_free_path(path); 301 return PTR_ERR(trans); 302 } 303 trans->block_rsv = &BTRFS_I(inode)->block_rsv; 304 305 if (compressed_size && compressed_pages) 306 extent_item_size = btrfs_file_extent_calc_inline_size( 307 compressed_size); 308 else 309 extent_item_size = btrfs_file_extent_calc_inline_size( 310 inline_len); 311 312 ret = __btrfs_drop_extents(trans, root, inode, path, 313 start, aligned_end, NULL, 314 1, 1, extent_item_size, &extent_inserted); 315 if (ret) { 316 btrfs_abort_transaction(trans, ret); 317 goto out; 318 } 319 320 if (isize > actual_end) 321 inline_len = min_t(u64, isize, actual_end); 322 ret = insert_inline_extent(trans, path, extent_inserted, 323 root, inode, start, 324 inline_len, compressed_size, 325 compress_type, compressed_pages); 326 if (ret && ret != -ENOSPC) { 327 btrfs_abort_transaction(trans, ret); 328 goto out; 329 } else if (ret == -ENOSPC) { 330 ret = 1; 331 goto out; 332 } 333 334 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 335 btrfs_drop_extent_cache(BTRFS_I(inode), start, aligned_end - 1, 0); 336 out: 337 /* 338 * Don't forget to free the reserved space, as for inlined extent 339 * it won't count as data extent, free them directly here. 340 * And at reserve time, it's always aligned to page size, so 341 * just free one page here. 342 */ 343 btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE); 344 btrfs_free_path(path); 345 btrfs_end_transaction(trans); 346 return ret; 347 } 348 349 struct async_extent { 350 u64 start; 351 u64 ram_size; 352 u64 compressed_size; 353 struct page **pages; 354 unsigned long nr_pages; 355 int compress_type; 356 struct list_head list; 357 }; 358 359 struct async_cow { 360 struct inode *inode; 361 struct btrfs_root *root; 362 struct page *locked_page; 363 u64 start; 364 u64 end; 365 unsigned int write_flags; 366 struct list_head extents; 367 struct btrfs_work work; 368 }; 369 370 static noinline int add_async_extent(struct async_cow *cow, 371 u64 start, u64 ram_size, 372 u64 compressed_size, 373 struct page **pages, 374 unsigned long nr_pages, 375 int compress_type) 376 { 377 struct async_extent *async_extent; 378 379 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); 380 BUG_ON(!async_extent); /* -ENOMEM */ 381 async_extent->start = start; 382 async_extent->ram_size = ram_size; 383 async_extent->compressed_size = compressed_size; 384 async_extent->pages = pages; 385 async_extent->nr_pages = nr_pages; 386 async_extent->compress_type = compress_type; 387 list_add_tail(&async_extent->list, &cow->extents); 388 return 0; 389 } 390 391 static inline int inode_need_compress(struct inode *inode, u64 start, u64 end) 392 { 393 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 394 395 /* force compress */ 396 if (btrfs_test_opt(fs_info, FORCE_COMPRESS)) 397 return 1; 398 /* defrag ioctl */ 399 if (BTRFS_I(inode)->defrag_compress) 400 return 1; 401 /* bad compression ratios */ 402 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) 403 return 0; 404 if (btrfs_test_opt(fs_info, COMPRESS) || 405 BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS || 406 BTRFS_I(inode)->prop_compress) 407 return btrfs_compress_heuristic(inode, start, end); 408 return 0; 409 } 410 411 static inline void inode_should_defrag(struct btrfs_inode *inode, 412 u64 start, u64 end, u64 num_bytes, u64 small_write) 413 { 414 /* If this is a small write inside eof, kick off a defrag */ 415 if (num_bytes < small_write && 416 (start > 0 || end + 1 < inode->disk_i_size)) 417 btrfs_add_inode_defrag(NULL, inode); 418 } 419 420 /* 421 * we create compressed extents in two phases. The first 422 * phase compresses a range of pages that have already been 423 * locked (both pages and state bits are locked). 424 * 425 * This is done inside an ordered work queue, and the compression 426 * is spread across many cpus. The actual IO submission is step 427 * two, and the ordered work queue takes care of making sure that 428 * happens in the same order things were put onto the queue by 429 * writepages and friends. 430 * 431 * If this code finds it can't get good compression, it puts an 432 * entry onto the work queue to write the uncompressed bytes. This 433 * makes sure that both compressed inodes and uncompressed inodes 434 * are written in the same order that the flusher thread sent them 435 * down. 436 */ 437 static noinline void compress_file_range(struct inode *inode, 438 struct page *locked_page, 439 u64 start, u64 end, 440 struct async_cow *async_cow, 441 int *num_added) 442 { 443 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 444 u64 blocksize = fs_info->sectorsize; 445 u64 actual_end; 446 u64 isize = i_size_read(inode); 447 int ret = 0; 448 struct page **pages = NULL; 449 unsigned long nr_pages; 450 unsigned long total_compressed = 0; 451 unsigned long total_in = 0; 452 int i; 453 int will_compress; 454 int compress_type = fs_info->compress_type; 455 int redirty = 0; 456 457 inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1, 458 SZ_16K); 459 460 actual_end = min_t(u64, isize, end + 1); 461 again: 462 will_compress = 0; 463 nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; 464 BUILD_BUG_ON((BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0); 465 nr_pages = min_t(unsigned long, nr_pages, 466 BTRFS_MAX_COMPRESSED / PAGE_SIZE); 467 468 /* 469 * we don't want to send crud past the end of i_size through 470 * compression, that's just a waste of CPU time. So, if the 471 * end of the file is before the start of our current 472 * requested range of bytes, we bail out to the uncompressed 473 * cleanup code that can deal with all of this. 474 * 475 * It isn't really the fastest way to fix things, but this is a 476 * very uncommon corner. 477 */ 478 if (actual_end <= start) 479 goto cleanup_and_bail_uncompressed; 480 481 total_compressed = actual_end - start; 482 483 /* 484 * skip compression for a small file range(<=blocksize) that 485 * isn't an inline extent, since it doesn't save disk space at all. 486 */ 487 if (total_compressed <= blocksize && 488 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) 489 goto cleanup_and_bail_uncompressed; 490 491 total_compressed = min_t(unsigned long, total_compressed, 492 BTRFS_MAX_UNCOMPRESSED); 493 total_in = 0; 494 ret = 0; 495 496 /* 497 * we do compression for mount -o compress and when the 498 * inode has not been flagged as nocompress. This flag can 499 * change at any time if we discover bad compression ratios. 500 */ 501 if (inode_need_compress(inode, start, end)) { 502 WARN_ON(pages); 503 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); 504 if (!pages) { 505 /* just bail out to the uncompressed code */ 506 goto cont; 507 } 508 509 if (BTRFS_I(inode)->defrag_compress) 510 compress_type = BTRFS_I(inode)->defrag_compress; 511 else if (BTRFS_I(inode)->prop_compress) 512 compress_type = BTRFS_I(inode)->prop_compress; 513 514 /* 515 * we need to call clear_page_dirty_for_io on each 516 * page in the range. Otherwise applications with the file 517 * mmap'd can wander in and change the page contents while 518 * we are compressing them. 519 * 520 * If the compression fails for any reason, we set the pages 521 * dirty again later on. 522 * 523 * Note that the remaining part is redirtied, the start pointer 524 * has moved, the end is the original one. 525 */ 526 if (!redirty) { 527 extent_range_clear_dirty_for_io(inode, start, end); 528 redirty = 1; 529 } 530 531 /* Compression level is applied here and only here */ 532 ret = btrfs_compress_pages( 533 compress_type | (fs_info->compress_level << 4), 534 inode->i_mapping, start, 535 pages, 536 &nr_pages, 537 &total_in, 538 &total_compressed); 539 540 if (!ret) { 541 unsigned long offset = total_compressed & 542 (PAGE_SIZE - 1); 543 struct page *page = pages[nr_pages - 1]; 544 char *kaddr; 545 546 /* zero the tail end of the last page, we might be 547 * sending it down to disk 548 */ 549 if (offset) { 550 kaddr = kmap_atomic(page); 551 memset(kaddr + offset, 0, 552 PAGE_SIZE - offset); 553 kunmap_atomic(kaddr); 554 } 555 will_compress = 1; 556 } 557 } 558 cont: 559 if (start == 0) { 560 /* lets try to make an inline extent */ 561 if (ret || total_in < actual_end) { 562 /* we didn't compress the entire range, try 563 * to make an uncompressed inline extent. 564 */ 565 ret = cow_file_range_inline(inode, start, end, 0, 566 BTRFS_COMPRESS_NONE, NULL); 567 } else { 568 /* try making a compressed inline extent */ 569 ret = cow_file_range_inline(inode, start, end, 570 total_compressed, 571 compress_type, pages); 572 } 573 if (ret <= 0) { 574 unsigned long clear_flags = EXTENT_DELALLOC | 575 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | 576 EXTENT_DO_ACCOUNTING; 577 unsigned long page_error_op; 578 579 page_error_op = ret < 0 ? PAGE_SET_ERROR : 0; 580 581 /* 582 * inline extent creation worked or returned error, 583 * we don't need to create any more async work items. 584 * Unlock and free up our temp pages. 585 * 586 * We use DO_ACCOUNTING here because we need the 587 * delalloc_release_metadata to be done _after_ we drop 588 * our outstanding extent for clearing delalloc for this 589 * range. 590 */ 591 extent_clear_unlock_delalloc(inode, start, end, end, 592 NULL, clear_flags, 593 PAGE_UNLOCK | 594 PAGE_CLEAR_DIRTY | 595 PAGE_SET_WRITEBACK | 596 page_error_op | 597 PAGE_END_WRITEBACK); 598 goto free_pages_out; 599 } 600 } 601 602 if (will_compress) { 603 /* 604 * we aren't doing an inline extent round the compressed size 605 * up to a block size boundary so the allocator does sane 606 * things 607 */ 608 total_compressed = ALIGN(total_compressed, blocksize); 609 610 /* 611 * one last check to make sure the compression is really a 612 * win, compare the page count read with the blocks on disk, 613 * compression must free at least one sector size 614 */ 615 total_in = ALIGN(total_in, PAGE_SIZE); 616 if (total_compressed + blocksize <= total_in) { 617 *num_added += 1; 618 619 /* 620 * The async work queues will take care of doing actual 621 * allocation on disk for these compressed pages, and 622 * will submit them to the elevator. 623 */ 624 add_async_extent(async_cow, start, total_in, 625 total_compressed, pages, nr_pages, 626 compress_type); 627 628 if (start + total_in < end) { 629 start += total_in; 630 pages = NULL; 631 cond_resched(); 632 goto again; 633 } 634 return; 635 } 636 } 637 if (pages) { 638 /* 639 * the compression code ran but failed to make things smaller, 640 * free any pages it allocated and our page pointer array 641 */ 642 for (i = 0; i < nr_pages; i++) { 643 WARN_ON(pages[i]->mapping); 644 put_page(pages[i]); 645 } 646 kfree(pages); 647 pages = NULL; 648 total_compressed = 0; 649 nr_pages = 0; 650 651 /* flag the file so we don't compress in the future */ 652 if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) && 653 !(BTRFS_I(inode)->prop_compress)) { 654 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; 655 } 656 } 657 cleanup_and_bail_uncompressed: 658 /* 659 * No compression, but we still need to write the pages in the file 660 * we've been given so far. redirty the locked page if it corresponds 661 * to our extent and set things up for the async work queue to run 662 * cow_file_range to do the normal delalloc dance. 663 */ 664 if (page_offset(locked_page) >= start && 665 page_offset(locked_page) <= end) 666 __set_page_dirty_nobuffers(locked_page); 667 /* unlocked later on in the async handlers */ 668 669 if (redirty) 670 extent_range_redirty_for_io(inode, start, end); 671 add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0, 672 BTRFS_COMPRESS_NONE); 673 *num_added += 1; 674 675 return; 676 677 free_pages_out: 678 for (i = 0; i < nr_pages; i++) { 679 WARN_ON(pages[i]->mapping); 680 put_page(pages[i]); 681 } 682 kfree(pages); 683 } 684 685 static void free_async_extent_pages(struct async_extent *async_extent) 686 { 687 int i; 688 689 if (!async_extent->pages) 690 return; 691 692 for (i = 0; i < async_extent->nr_pages; i++) { 693 WARN_ON(async_extent->pages[i]->mapping); 694 put_page(async_extent->pages[i]); 695 } 696 kfree(async_extent->pages); 697 async_extent->nr_pages = 0; 698 async_extent->pages = NULL; 699 } 700 701 /* 702 * phase two of compressed writeback. This is the ordered portion 703 * of the code, which only gets called in the order the work was 704 * queued. We walk all the async extents created by compress_file_range 705 * and send them down to the disk. 706 */ 707 static noinline void submit_compressed_extents(struct inode *inode, 708 struct async_cow *async_cow) 709 { 710 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 711 struct async_extent *async_extent; 712 u64 alloc_hint = 0; 713 struct btrfs_key ins; 714 struct extent_map *em; 715 struct btrfs_root *root = BTRFS_I(inode)->root; 716 struct extent_io_tree *io_tree; 717 int ret = 0; 718 719 again: 720 while (!list_empty(&async_cow->extents)) { 721 async_extent = list_entry(async_cow->extents.next, 722 struct async_extent, list); 723 list_del(&async_extent->list); 724 725 io_tree = &BTRFS_I(inode)->io_tree; 726 727 retry: 728 /* did the compression code fall back to uncompressed IO? */ 729 if (!async_extent->pages) { 730 int page_started = 0; 731 unsigned long nr_written = 0; 732 733 lock_extent(io_tree, async_extent->start, 734 async_extent->start + 735 async_extent->ram_size - 1); 736 737 /* allocate blocks */ 738 ret = cow_file_range(inode, async_cow->locked_page, 739 async_extent->start, 740 async_extent->start + 741 async_extent->ram_size - 1, 742 async_extent->start + 743 async_extent->ram_size - 1, 744 &page_started, &nr_written, 0, 745 NULL); 746 747 /* JDM XXX */ 748 749 /* 750 * if page_started, cow_file_range inserted an 751 * inline extent and took care of all the unlocking 752 * and IO for us. Otherwise, we need to submit 753 * all those pages down to the drive. 754 */ 755 if (!page_started && !ret) 756 extent_write_locked_range(inode, 757 async_extent->start, 758 async_extent->start + 759 async_extent->ram_size - 1, 760 WB_SYNC_ALL); 761 else if (ret) 762 unlock_page(async_cow->locked_page); 763 kfree(async_extent); 764 cond_resched(); 765 continue; 766 } 767 768 lock_extent(io_tree, async_extent->start, 769 async_extent->start + async_extent->ram_size - 1); 770 771 ret = btrfs_reserve_extent(root, async_extent->ram_size, 772 async_extent->compressed_size, 773 async_extent->compressed_size, 774 0, alloc_hint, &ins, 1, 1); 775 if (ret) { 776 free_async_extent_pages(async_extent); 777 778 if (ret == -ENOSPC) { 779 unlock_extent(io_tree, async_extent->start, 780 async_extent->start + 781 async_extent->ram_size - 1); 782 783 /* 784 * we need to redirty the pages if we decide to 785 * fallback to uncompressed IO, otherwise we 786 * will not submit these pages down to lower 787 * layers. 788 */ 789 extent_range_redirty_for_io(inode, 790 async_extent->start, 791 async_extent->start + 792 async_extent->ram_size - 1); 793 794 goto retry; 795 } 796 goto out_free; 797 } 798 /* 799 * here we're doing allocation and writeback of the 800 * compressed pages 801 */ 802 em = create_io_em(inode, async_extent->start, 803 async_extent->ram_size, /* len */ 804 async_extent->start, /* orig_start */ 805 ins.objectid, /* block_start */ 806 ins.offset, /* block_len */ 807 ins.offset, /* orig_block_len */ 808 async_extent->ram_size, /* ram_bytes */ 809 async_extent->compress_type, 810 BTRFS_ORDERED_COMPRESSED); 811 if (IS_ERR(em)) 812 /* ret value is not necessary due to void function */ 813 goto out_free_reserve; 814 free_extent_map(em); 815 816 ret = btrfs_add_ordered_extent_compress(inode, 817 async_extent->start, 818 ins.objectid, 819 async_extent->ram_size, 820 ins.offset, 821 BTRFS_ORDERED_COMPRESSED, 822 async_extent->compress_type); 823 if (ret) { 824 btrfs_drop_extent_cache(BTRFS_I(inode), 825 async_extent->start, 826 async_extent->start + 827 async_extent->ram_size - 1, 0); 828 goto out_free_reserve; 829 } 830 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 831 832 /* 833 * clear dirty, set writeback and unlock the pages. 834 */ 835 extent_clear_unlock_delalloc(inode, async_extent->start, 836 async_extent->start + 837 async_extent->ram_size - 1, 838 async_extent->start + 839 async_extent->ram_size - 1, 840 NULL, EXTENT_LOCKED | EXTENT_DELALLOC, 841 PAGE_UNLOCK | PAGE_CLEAR_DIRTY | 842 PAGE_SET_WRITEBACK); 843 if (btrfs_submit_compressed_write(inode, 844 async_extent->start, 845 async_extent->ram_size, 846 ins.objectid, 847 ins.offset, async_extent->pages, 848 async_extent->nr_pages, 849 async_cow->write_flags)) { 850 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; 851 struct page *p = async_extent->pages[0]; 852 const u64 start = async_extent->start; 853 const u64 end = start + async_extent->ram_size - 1; 854 855 p->mapping = inode->i_mapping; 856 tree->ops->writepage_end_io_hook(p, start, end, 857 NULL, 0); 858 p->mapping = NULL; 859 extent_clear_unlock_delalloc(inode, start, end, end, 860 NULL, 0, 861 PAGE_END_WRITEBACK | 862 PAGE_SET_ERROR); 863 free_async_extent_pages(async_extent); 864 } 865 alloc_hint = ins.objectid + ins.offset; 866 kfree(async_extent); 867 cond_resched(); 868 } 869 return; 870 out_free_reserve: 871 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 872 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); 873 out_free: 874 extent_clear_unlock_delalloc(inode, async_extent->start, 875 async_extent->start + 876 async_extent->ram_size - 1, 877 async_extent->start + 878 async_extent->ram_size - 1, 879 NULL, EXTENT_LOCKED | EXTENT_DELALLOC | 880 EXTENT_DELALLOC_NEW | 881 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, 882 PAGE_UNLOCK | PAGE_CLEAR_DIRTY | 883 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK | 884 PAGE_SET_ERROR); 885 free_async_extent_pages(async_extent); 886 kfree(async_extent); 887 goto again; 888 } 889 890 static u64 get_extent_allocation_hint(struct inode *inode, u64 start, 891 u64 num_bytes) 892 { 893 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 894 struct extent_map *em; 895 u64 alloc_hint = 0; 896 897 read_lock(&em_tree->lock); 898 em = search_extent_mapping(em_tree, start, num_bytes); 899 if (em) { 900 /* 901 * if block start isn't an actual block number then find the 902 * first block in this inode and use that as a hint. If that 903 * block is also bogus then just don't worry about it. 904 */ 905 if (em->block_start >= EXTENT_MAP_LAST_BYTE) { 906 free_extent_map(em); 907 em = search_extent_mapping(em_tree, 0, 0); 908 if (em && em->block_start < EXTENT_MAP_LAST_BYTE) 909 alloc_hint = em->block_start; 910 if (em) 911 free_extent_map(em); 912 } else { 913 alloc_hint = em->block_start; 914 free_extent_map(em); 915 } 916 } 917 read_unlock(&em_tree->lock); 918 919 return alloc_hint; 920 } 921 922 /* 923 * when extent_io.c finds a delayed allocation range in the file, 924 * the call backs end up in this code. The basic idea is to 925 * allocate extents on disk for the range, and create ordered data structs 926 * in ram to track those extents. 927 * 928 * locked_page is the page that writepage had locked already. We use 929 * it to make sure we don't do extra locks or unlocks. 930 * 931 * *page_started is set to one if we unlock locked_page and do everything 932 * required to start IO on it. It may be clean and already done with 933 * IO when we return. 934 */ 935 static noinline int cow_file_range(struct inode *inode, 936 struct page *locked_page, 937 u64 start, u64 end, u64 delalloc_end, 938 int *page_started, unsigned long *nr_written, 939 int unlock, struct btrfs_dedupe_hash *hash) 940 { 941 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 942 struct btrfs_root *root = BTRFS_I(inode)->root; 943 u64 alloc_hint = 0; 944 u64 num_bytes; 945 unsigned long ram_size; 946 u64 cur_alloc_size = 0; 947 u64 blocksize = fs_info->sectorsize; 948 struct btrfs_key ins; 949 struct extent_map *em; 950 unsigned clear_bits; 951 unsigned long page_ops; 952 bool extent_reserved = false; 953 int ret = 0; 954 955 if (btrfs_is_free_space_inode(BTRFS_I(inode))) { 956 WARN_ON_ONCE(1); 957 ret = -EINVAL; 958 goto out_unlock; 959 } 960 961 num_bytes = ALIGN(end - start + 1, blocksize); 962 num_bytes = max(blocksize, num_bytes); 963 ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy)); 964 965 inode_should_defrag(BTRFS_I(inode), start, end, num_bytes, SZ_64K); 966 967 if (start == 0) { 968 /* lets try to make an inline extent */ 969 ret = cow_file_range_inline(inode, start, end, 0, 970 BTRFS_COMPRESS_NONE, NULL); 971 if (ret == 0) { 972 /* 973 * We use DO_ACCOUNTING here because we need the 974 * delalloc_release_metadata to be run _after_ we drop 975 * our outstanding extent for clearing delalloc for this 976 * range. 977 */ 978 extent_clear_unlock_delalloc(inode, start, end, 979 delalloc_end, NULL, 980 EXTENT_LOCKED | EXTENT_DELALLOC | 981 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | 982 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | 983 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | 984 PAGE_END_WRITEBACK); 985 *nr_written = *nr_written + 986 (end - start + PAGE_SIZE) / PAGE_SIZE; 987 *page_started = 1; 988 goto out; 989 } else if (ret < 0) { 990 goto out_unlock; 991 } 992 } 993 994 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); 995 btrfs_drop_extent_cache(BTRFS_I(inode), start, 996 start + num_bytes - 1, 0); 997 998 while (num_bytes > 0) { 999 cur_alloc_size = num_bytes; 1000 ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size, 1001 fs_info->sectorsize, 0, alloc_hint, 1002 &ins, 1, 1); 1003 if (ret < 0) 1004 goto out_unlock; 1005 cur_alloc_size = ins.offset; 1006 extent_reserved = true; 1007 1008 ram_size = ins.offset; 1009 em = create_io_em(inode, start, ins.offset, /* len */ 1010 start, /* orig_start */ 1011 ins.objectid, /* block_start */ 1012 ins.offset, /* block_len */ 1013 ins.offset, /* orig_block_len */ 1014 ram_size, /* ram_bytes */ 1015 BTRFS_COMPRESS_NONE, /* compress_type */ 1016 BTRFS_ORDERED_REGULAR /* type */); 1017 if (IS_ERR(em)) { 1018 ret = PTR_ERR(em); 1019 goto out_reserve; 1020 } 1021 free_extent_map(em); 1022 1023 ret = btrfs_add_ordered_extent(inode, start, ins.objectid, 1024 ram_size, cur_alloc_size, 0); 1025 if (ret) 1026 goto out_drop_extent_cache; 1027 1028 if (root->root_key.objectid == 1029 BTRFS_DATA_RELOC_TREE_OBJECTID) { 1030 ret = btrfs_reloc_clone_csums(inode, start, 1031 cur_alloc_size); 1032 /* 1033 * Only drop cache here, and process as normal. 1034 * 1035 * We must not allow extent_clear_unlock_delalloc() 1036 * at out_unlock label to free meta of this ordered 1037 * extent, as its meta should be freed by 1038 * btrfs_finish_ordered_io(). 1039 * 1040 * So we must continue until @start is increased to 1041 * skip current ordered extent. 1042 */ 1043 if (ret) 1044 btrfs_drop_extent_cache(BTRFS_I(inode), start, 1045 start + ram_size - 1, 0); 1046 } 1047 1048 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 1049 1050 /* we're not doing compressed IO, don't unlock the first 1051 * page (which the caller expects to stay locked), don't 1052 * clear any dirty bits and don't set any writeback bits 1053 * 1054 * Do set the Private2 bit so we know this page was properly 1055 * setup for writepage 1056 */ 1057 page_ops = unlock ? PAGE_UNLOCK : 0; 1058 page_ops |= PAGE_SET_PRIVATE2; 1059 1060 extent_clear_unlock_delalloc(inode, start, 1061 start + ram_size - 1, 1062 delalloc_end, locked_page, 1063 EXTENT_LOCKED | EXTENT_DELALLOC, 1064 page_ops); 1065 if (num_bytes < cur_alloc_size) 1066 num_bytes = 0; 1067 else 1068 num_bytes -= cur_alloc_size; 1069 alloc_hint = ins.objectid + ins.offset; 1070 start += cur_alloc_size; 1071 extent_reserved = false; 1072 1073 /* 1074 * btrfs_reloc_clone_csums() error, since start is increased 1075 * extent_clear_unlock_delalloc() at out_unlock label won't 1076 * free metadata of current ordered extent, we're OK to exit. 1077 */ 1078 if (ret) 1079 goto out_unlock; 1080 } 1081 out: 1082 return ret; 1083 1084 out_drop_extent_cache: 1085 btrfs_drop_extent_cache(BTRFS_I(inode), start, start + ram_size - 1, 0); 1086 out_reserve: 1087 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 1088 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); 1089 out_unlock: 1090 clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | 1091 EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV; 1092 page_ops = PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK | 1093 PAGE_END_WRITEBACK; 1094 /* 1095 * If we reserved an extent for our delalloc range (or a subrange) and 1096 * failed to create the respective ordered extent, then it means that 1097 * when we reserved the extent we decremented the extent's size from 1098 * the data space_info's bytes_may_use counter and incremented the 1099 * space_info's bytes_reserved counter by the same amount. We must make 1100 * sure extent_clear_unlock_delalloc() does not try to decrement again 1101 * the data space_info's bytes_may_use counter, therefore we do not pass 1102 * it the flag EXTENT_CLEAR_DATA_RESV. 1103 */ 1104 if (extent_reserved) { 1105 extent_clear_unlock_delalloc(inode, start, 1106 start + cur_alloc_size, 1107 start + cur_alloc_size, 1108 locked_page, 1109 clear_bits, 1110 page_ops); 1111 start += cur_alloc_size; 1112 if (start >= end) 1113 goto out; 1114 } 1115 extent_clear_unlock_delalloc(inode, start, end, delalloc_end, 1116 locked_page, 1117 clear_bits | EXTENT_CLEAR_DATA_RESV, 1118 page_ops); 1119 goto out; 1120 } 1121 1122 /* 1123 * work queue call back to started compression on a file and pages 1124 */ 1125 static noinline void async_cow_start(struct btrfs_work *work) 1126 { 1127 struct async_cow *async_cow; 1128 int num_added = 0; 1129 async_cow = container_of(work, struct async_cow, work); 1130 1131 compress_file_range(async_cow->inode, async_cow->locked_page, 1132 async_cow->start, async_cow->end, async_cow, 1133 &num_added); 1134 if (num_added == 0) { 1135 btrfs_add_delayed_iput(async_cow->inode); 1136 async_cow->inode = NULL; 1137 } 1138 } 1139 1140 /* 1141 * work queue call back to submit previously compressed pages 1142 */ 1143 static noinline void async_cow_submit(struct btrfs_work *work) 1144 { 1145 struct btrfs_fs_info *fs_info; 1146 struct async_cow *async_cow; 1147 struct btrfs_root *root; 1148 unsigned long nr_pages; 1149 1150 async_cow = container_of(work, struct async_cow, work); 1151 1152 root = async_cow->root; 1153 fs_info = root->fs_info; 1154 nr_pages = (async_cow->end - async_cow->start + PAGE_SIZE) >> 1155 PAGE_SHIFT; 1156 1157 /* atomic_sub_return implies a barrier */ 1158 if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) < 1159 5 * SZ_1M) 1160 cond_wake_up_nomb(&fs_info->async_submit_wait); 1161 1162 if (async_cow->inode) 1163 submit_compressed_extents(async_cow->inode, async_cow); 1164 } 1165 1166 static noinline void async_cow_free(struct btrfs_work *work) 1167 { 1168 struct async_cow *async_cow; 1169 async_cow = container_of(work, struct async_cow, work); 1170 if (async_cow->inode) 1171 btrfs_add_delayed_iput(async_cow->inode); 1172 kfree(async_cow); 1173 } 1174 1175 static int cow_file_range_async(struct inode *inode, struct page *locked_page, 1176 u64 start, u64 end, int *page_started, 1177 unsigned long *nr_written, 1178 unsigned int write_flags) 1179 { 1180 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1181 struct async_cow *async_cow; 1182 struct btrfs_root *root = BTRFS_I(inode)->root; 1183 unsigned long nr_pages; 1184 u64 cur_end; 1185 1186 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED, 1187 1, 0, NULL); 1188 while (start < end) { 1189 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); 1190 BUG_ON(!async_cow); /* -ENOMEM */ 1191 async_cow->inode = igrab(inode); 1192 async_cow->root = root; 1193 async_cow->locked_page = locked_page; 1194 async_cow->start = start; 1195 async_cow->write_flags = write_flags; 1196 1197 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS && 1198 !btrfs_test_opt(fs_info, FORCE_COMPRESS)) 1199 cur_end = end; 1200 else 1201 cur_end = min(end, start + SZ_512K - 1); 1202 1203 async_cow->end = cur_end; 1204 INIT_LIST_HEAD(&async_cow->extents); 1205 1206 btrfs_init_work(&async_cow->work, 1207 btrfs_delalloc_helper, 1208 async_cow_start, async_cow_submit, 1209 async_cow_free); 1210 1211 nr_pages = (cur_end - start + PAGE_SIZE) >> 1212 PAGE_SHIFT; 1213 atomic_add(nr_pages, &fs_info->async_delalloc_pages); 1214 1215 btrfs_queue_work(fs_info->delalloc_workers, &async_cow->work); 1216 1217 *nr_written += nr_pages; 1218 start = cur_end + 1; 1219 } 1220 *page_started = 1; 1221 return 0; 1222 } 1223 1224 static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info, 1225 u64 bytenr, u64 num_bytes) 1226 { 1227 int ret; 1228 struct btrfs_ordered_sum *sums; 1229 LIST_HEAD(list); 1230 1231 ret = btrfs_lookup_csums_range(fs_info->csum_root, bytenr, 1232 bytenr + num_bytes - 1, &list, 0); 1233 if (ret == 0 && list_empty(&list)) 1234 return 0; 1235 1236 while (!list_empty(&list)) { 1237 sums = list_entry(list.next, struct btrfs_ordered_sum, list); 1238 list_del(&sums->list); 1239 kfree(sums); 1240 } 1241 if (ret < 0) 1242 return ret; 1243 return 1; 1244 } 1245 1246 /* 1247 * when nowcow writeback call back. This checks for snapshots or COW copies 1248 * of the extents that exist in the file, and COWs the file as required. 1249 * 1250 * If no cow copies or snapshots exist, we write directly to the existing 1251 * blocks on disk 1252 */ 1253 static noinline int run_delalloc_nocow(struct inode *inode, 1254 struct page *locked_page, 1255 u64 start, u64 end, int *page_started, int force, 1256 unsigned long *nr_written) 1257 { 1258 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1259 struct btrfs_root *root = BTRFS_I(inode)->root; 1260 struct extent_buffer *leaf; 1261 struct btrfs_path *path; 1262 struct btrfs_file_extent_item *fi; 1263 struct btrfs_key found_key; 1264 struct extent_map *em; 1265 u64 cow_start; 1266 u64 cur_offset; 1267 u64 extent_end; 1268 u64 extent_offset; 1269 u64 disk_bytenr; 1270 u64 num_bytes; 1271 u64 disk_num_bytes; 1272 u64 ram_bytes; 1273 int extent_type; 1274 int ret, err; 1275 int type; 1276 int nocow; 1277 int check_prev = 1; 1278 bool nolock; 1279 u64 ino = btrfs_ino(BTRFS_I(inode)); 1280 1281 path = btrfs_alloc_path(); 1282 if (!path) { 1283 extent_clear_unlock_delalloc(inode, start, end, end, 1284 locked_page, 1285 EXTENT_LOCKED | EXTENT_DELALLOC | 1286 EXTENT_DO_ACCOUNTING | 1287 EXTENT_DEFRAG, PAGE_UNLOCK | 1288 PAGE_CLEAR_DIRTY | 1289 PAGE_SET_WRITEBACK | 1290 PAGE_END_WRITEBACK); 1291 return -ENOMEM; 1292 } 1293 1294 nolock = btrfs_is_free_space_inode(BTRFS_I(inode)); 1295 1296 cow_start = (u64)-1; 1297 cur_offset = start; 1298 while (1) { 1299 ret = btrfs_lookup_file_extent(NULL, root, path, ino, 1300 cur_offset, 0); 1301 if (ret < 0) 1302 goto error; 1303 if (ret > 0 && path->slots[0] > 0 && check_prev) { 1304 leaf = path->nodes[0]; 1305 btrfs_item_key_to_cpu(leaf, &found_key, 1306 path->slots[0] - 1); 1307 if (found_key.objectid == ino && 1308 found_key.type == BTRFS_EXTENT_DATA_KEY) 1309 path->slots[0]--; 1310 } 1311 check_prev = 0; 1312 next_slot: 1313 leaf = path->nodes[0]; 1314 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1315 ret = btrfs_next_leaf(root, path); 1316 if (ret < 0) { 1317 if (cow_start != (u64)-1) 1318 cur_offset = cow_start; 1319 goto error; 1320 } 1321 if (ret > 0) 1322 break; 1323 leaf = path->nodes[0]; 1324 } 1325 1326 nocow = 0; 1327 disk_bytenr = 0; 1328 num_bytes = 0; 1329 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1330 1331 if (found_key.objectid > ino) 1332 break; 1333 if (WARN_ON_ONCE(found_key.objectid < ino) || 1334 found_key.type < BTRFS_EXTENT_DATA_KEY) { 1335 path->slots[0]++; 1336 goto next_slot; 1337 } 1338 if (found_key.type > BTRFS_EXTENT_DATA_KEY || 1339 found_key.offset > end) 1340 break; 1341 1342 if (found_key.offset > cur_offset) { 1343 extent_end = found_key.offset; 1344 extent_type = 0; 1345 goto out_check; 1346 } 1347 1348 fi = btrfs_item_ptr(leaf, path->slots[0], 1349 struct btrfs_file_extent_item); 1350 extent_type = btrfs_file_extent_type(leaf, fi); 1351 1352 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); 1353 if (extent_type == BTRFS_FILE_EXTENT_REG || 1354 extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1355 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 1356 extent_offset = btrfs_file_extent_offset(leaf, fi); 1357 extent_end = found_key.offset + 1358 btrfs_file_extent_num_bytes(leaf, fi); 1359 disk_num_bytes = 1360 btrfs_file_extent_disk_num_bytes(leaf, fi); 1361 if (extent_end <= start) { 1362 path->slots[0]++; 1363 goto next_slot; 1364 } 1365 if (disk_bytenr == 0) 1366 goto out_check; 1367 if (btrfs_file_extent_compression(leaf, fi) || 1368 btrfs_file_extent_encryption(leaf, fi) || 1369 btrfs_file_extent_other_encoding(leaf, fi)) 1370 goto out_check; 1371 /* 1372 * Do the same check as in btrfs_cross_ref_exist but 1373 * without the unnecessary search. 1374 */ 1375 if (btrfs_file_extent_generation(leaf, fi) <= 1376 btrfs_root_last_snapshot(&root->root_item)) 1377 goto out_check; 1378 if (extent_type == BTRFS_FILE_EXTENT_REG && !force) 1379 goto out_check; 1380 if (btrfs_extent_readonly(fs_info, disk_bytenr)) 1381 goto out_check; 1382 ret = btrfs_cross_ref_exist(root, ino, 1383 found_key.offset - 1384 extent_offset, disk_bytenr); 1385 if (ret) { 1386 /* 1387 * ret could be -EIO if the above fails to read 1388 * metadata. 1389 */ 1390 if (ret < 0) { 1391 if (cow_start != (u64)-1) 1392 cur_offset = cow_start; 1393 goto error; 1394 } 1395 1396 WARN_ON_ONCE(nolock); 1397 goto out_check; 1398 } 1399 disk_bytenr += extent_offset; 1400 disk_bytenr += cur_offset - found_key.offset; 1401 num_bytes = min(end + 1, extent_end) - cur_offset; 1402 /* 1403 * if there are pending snapshots for this root, 1404 * we fall into common COW way. 1405 */ 1406 if (!nolock) { 1407 err = btrfs_start_write_no_snapshotting(root); 1408 if (!err) 1409 goto out_check; 1410 } 1411 /* 1412 * force cow if csum exists in the range. 1413 * this ensure that csum for a given extent are 1414 * either valid or do not exist. 1415 */ 1416 ret = csum_exist_in_range(fs_info, disk_bytenr, 1417 num_bytes); 1418 if (ret) { 1419 if (!nolock) 1420 btrfs_end_write_no_snapshotting(root); 1421 1422 /* 1423 * ret could be -EIO if the above fails to read 1424 * metadata. 1425 */ 1426 if (ret < 0) { 1427 if (cow_start != (u64)-1) 1428 cur_offset = cow_start; 1429 goto error; 1430 } 1431 WARN_ON_ONCE(nolock); 1432 goto out_check; 1433 } 1434 if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr)) { 1435 if (!nolock) 1436 btrfs_end_write_no_snapshotting(root); 1437 goto out_check; 1438 } 1439 nocow = 1; 1440 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 1441 extent_end = found_key.offset + 1442 btrfs_file_extent_ram_bytes(leaf, fi); 1443 extent_end = ALIGN(extent_end, 1444 fs_info->sectorsize); 1445 } else { 1446 BUG_ON(1); 1447 } 1448 out_check: 1449 if (extent_end <= start) { 1450 path->slots[0]++; 1451 if (!nolock && nocow) 1452 btrfs_end_write_no_snapshotting(root); 1453 if (nocow) 1454 btrfs_dec_nocow_writers(fs_info, disk_bytenr); 1455 goto next_slot; 1456 } 1457 if (!nocow) { 1458 if (cow_start == (u64)-1) 1459 cow_start = cur_offset; 1460 cur_offset = extent_end; 1461 if (cur_offset > end) 1462 break; 1463 path->slots[0]++; 1464 goto next_slot; 1465 } 1466 1467 btrfs_release_path(path); 1468 if (cow_start != (u64)-1) { 1469 ret = cow_file_range(inode, locked_page, 1470 cow_start, found_key.offset - 1, 1471 end, page_started, nr_written, 1, 1472 NULL); 1473 if (ret) { 1474 if (!nolock && nocow) 1475 btrfs_end_write_no_snapshotting(root); 1476 if (nocow) 1477 btrfs_dec_nocow_writers(fs_info, 1478 disk_bytenr); 1479 goto error; 1480 } 1481 cow_start = (u64)-1; 1482 } 1483 1484 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1485 u64 orig_start = found_key.offset - extent_offset; 1486 1487 em = create_io_em(inode, cur_offset, num_bytes, 1488 orig_start, 1489 disk_bytenr, /* block_start */ 1490 num_bytes, /* block_len */ 1491 disk_num_bytes, /* orig_block_len */ 1492 ram_bytes, BTRFS_COMPRESS_NONE, 1493 BTRFS_ORDERED_PREALLOC); 1494 if (IS_ERR(em)) { 1495 if (!nolock && nocow) 1496 btrfs_end_write_no_snapshotting(root); 1497 if (nocow) 1498 btrfs_dec_nocow_writers(fs_info, 1499 disk_bytenr); 1500 ret = PTR_ERR(em); 1501 goto error; 1502 } 1503 free_extent_map(em); 1504 } 1505 1506 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { 1507 type = BTRFS_ORDERED_PREALLOC; 1508 } else { 1509 type = BTRFS_ORDERED_NOCOW; 1510 } 1511 1512 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr, 1513 num_bytes, num_bytes, type); 1514 if (nocow) 1515 btrfs_dec_nocow_writers(fs_info, disk_bytenr); 1516 BUG_ON(ret); /* -ENOMEM */ 1517 1518 if (root->root_key.objectid == 1519 BTRFS_DATA_RELOC_TREE_OBJECTID) 1520 /* 1521 * Error handled later, as we must prevent 1522 * extent_clear_unlock_delalloc() in error handler 1523 * from freeing metadata of created ordered extent. 1524 */ 1525 ret = btrfs_reloc_clone_csums(inode, cur_offset, 1526 num_bytes); 1527 1528 extent_clear_unlock_delalloc(inode, cur_offset, 1529 cur_offset + num_bytes - 1, end, 1530 locked_page, EXTENT_LOCKED | 1531 EXTENT_DELALLOC | 1532 EXTENT_CLEAR_DATA_RESV, 1533 PAGE_UNLOCK | PAGE_SET_PRIVATE2); 1534 1535 if (!nolock && nocow) 1536 btrfs_end_write_no_snapshotting(root); 1537 cur_offset = extent_end; 1538 1539 /* 1540 * btrfs_reloc_clone_csums() error, now we're OK to call error 1541 * handler, as metadata for created ordered extent will only 1542 * be freed by btrfs_finish_ordered_io(). 1543 */ 1544 if (ret) 1545 goto error; 1546 if (cur_offset > end) 1547 break; 1548 } 1549 btrfs_release_path(path); 1550 1551 if (cur_offset <= end && cow_start == (u64)-1) { 1552 cow_start = cur_offset; 1553 cur_offset = end; 1554 } 1555 1556 if (cow_start != (u64)-1) { 1557 ret = cow_file_range(inode, locked_page, cow_start, end, end, 1558 page_started, nr_written, 1, NULL); 1559 if (ret) 1560 goto error; 1561 } 1562 1563 error: 1564 if (ret && cur_offset < end) 1565 extent_clear_unlock_delalloc(inode, cur_offset, end, end, 1566 locked_page, EXTENT_LOCKED | 1567 EXTENT_DELALLOC | EXTENT_DEFRAG | 1568 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | 1569 PAGE_CLEAR_DIRTY | 1570 PAGE_SET_WRITEBACK | 1571 PAGE_END_WRITEBACK); 1572 btrfs_free_path(path); 1573 return ret; 1574 } 1575 1576 static inline int need_force_cow(struct inode *inode, u64 start, u64 end) 1577 { 1578 1579 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && 1580 !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)) 1581 return 0; 1582 1583 /* 1584 * @defrag_bytes is a hint value, no spinlock held here, 1585 * if is not zero, it means the file is defragging. 1586 * Force cow if given extent needs to be defragged. 1587 */ 1588 if (BTRFS_I(inode)->defrag_bytes && 1589 test_range_bit(&BTRFS_I(inode)->io_tree, start, end, 1590 EXTENT_DEFRAG, 0, NULL)) 1591 return 1; 1592 1593 return 0; 1594 } 1595 1596 /* 1597 * extent_io.c call back to do delayed allocation processing 1598 */ 1599 static int run_delalloc_range(void *private_data, struct page *locked_page, 1600 u64 start, u64 end, int *page_started, 1601 unsigned long *nr_written, 1602 struct writeback_control *wbc) 1603 { 1604 struct inode *inode = private_data; 1605 int ret; 1606 int force_cow = need_force_cow(inode, start, end); 1607 unsigned int write_flags = wbc_to_write_flags(wbc); 1608 1609 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW && !force_cow) { 1610 ret = run_delalloc_nocow(inode, locked_page, start, end, 1611 page_started, 1, nr_written); 1612 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC && !force_cow) { 1613 ret = run_delalloc_nocow(inode, locked_page, start, end, 1614 page_started, 0, nr_written); 1615 } else if (!inode_need_compress(inode, start, end)) { 1616 ret = cow_file_range(inode, locked_page, start, end, end, 1617 page_started, nr_written, 1, NULL); 1618 } else { 1619 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 1620 &BTRFS_I(inode)->runtime_flags); 1621 ret = cow_file_range_async(inode, locked_page, start, end, 1622 page_started, nr_written, 1623 write_flags); 1624 } 1625 if (ret) 1626 btrfs_cleanup_ordered_extents(inode, start, end - start + 1); 1627 return ret; 1628 } 1629 1630 static void btrfs_split_extent_hook(void *private_data, 1631 struct extent_state *orig, u64 split) 1632 { 1633 struct inode *inode = private_data; 1634 u64 size; 1635 1636 /* not delalloc, ignore it */ 1637 if (!(orig->state & EXTENT_DELALLOC)) 1638 return; 1639 1640 size = orig->end - orig->start + 1; 1641 if (size > BTRFS_MAX_EXTENT_SIZE) { 1642 u32 num_extents; 1643 u64 new_size; 1644 1645 /* 1646 * See the explanation in btrfs_merge_extent_hook, the same 1647 * applies here, just in reverse. 1648 */ 1649 new_size = orig->end - split + 1; 1650 num_extents = count_max_extents(new_size); 1651 new_size = split - orig->start; 1652 num_extents += count_max_extents(new_size); 1653 if (count_max_extents(size) >= num_extents) 1654 return; 1655 } 1656 1657 spin_lock(&BTRFS_I(inode)->lock); 1658 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1); 1659 spin_unlock(&BTRFS_I(inode)->lock); 1660 } 1661 1662 /* 1663 * extent_io.c merge_extent_hook, used to track merged delayed allocation 1664 * extents so we can keep track of new extents that are just merged onto old 1665 * extents, such as when we are doing sequential writes, so we can properly 1666 * account for the metadata space we'll need. 1667 */ 1668 static void btrfs_merge_extent_hook(void *private_data, 1669 struct extent_state *new, 1670 struct extent_state *other) 1671 { 1672 struct inode *inode = private_data; 1673 u64 new_size, old_size; 1674 u32 num_extents; 1675 1676 /* not delalloc, ignore it */ 1677 if (!(other->state & EXTENT_DELALLOC)) 1678 return; 1679 1680 if (new->start > other->start) 1681 new_size = new->end - other->start + 1; 1682 else 1683 new_size = other->end - new->start + 1; 1684 1685 /* we're not bigger than the max, unreserve the space and go */ 1686 if (new_size <= BTRFS_MAX_EXTENT_SIZE) { 1687 spin_lock(&BTRFS_I(inode)->lock); 1688 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1); 1689 spin_unlock(&BTRFS_I(inode)->lock); 1690 return; 1691 } 1692 1693 /* 1694 * We have to add up either side to figure out how many extents were 1695 * accounted for before we merged into one big extent. If the number of 1696 * extents we accounted for is <= the amount we need for the new range 1697 * then we can return, otherwise drop. Think of it like this 1698 * 1699 * [ 4k][MAX_SIZE] 1700 * 1701 * So we've grown the extent by a MAX_SIZE extent, this would mean we 1702 * need 2 outstanding extents, on one side we have 1 and the other side 1703 * we have 1 so they are == and we can return. But in this case 1704 * 1705 * [MAX_SIZE+4k][MAX_SIZE+4k] 1706 * 1707 * Each range on their own accounts for 2 extents, but merged together 1708 * they are only 3 extents worth of accounting, so we need to drop in 1709 * this case. 1710 */ 1711 old_size = other->end - other->start + 1; 1712 num_extents = count_max_extents(old_size); 1713 old_size = new->end - new->start + 1; 1714 num_extents += count_max_extents(old_size); 1715 if (count_max_extents(new_size) >= num_extents) 1716 return; 1717 1718 spin_lock(&BTRFS_I(inode)->lock); 1719 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1); 1720 spin_unlock(&BTRFS_I(inode)->lock); 1721 } 1722 1723 static void btrfs_add_delalloc_inodes(struct btrfs_root *root, 1724 struct inode *inode) 1725 { 1726 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1727 1728 spin_lock(&root->delalloc_lock); 1729 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) { 1730 list_add_tail(&BTRFS_I(inode)->delalloc_inodes, 1731 &root->delalloc_inodes); 1732 set_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1733 &BTRFS_I(inode)->runtime_flags); 1734 root->nr_delalloc_inodes++; 1735 if (root->nr_delalloc_inodes == 1) { 1736 spin_lock(&fs_info->delalloc_root_lock); 1737 BUG_ON(!list_empty(&root->delalloc_root)); 1738 list_add_tail(&root->delalloc_root, 1739 &fs_info->delalloc_roots); 1740 spin_unlock(&fs_info->delalloc_root_lock); 1741 } 1742 } 1743 spin_unlock(&root->delalloc_lock); 1744 } 1745 1746 1747 void __btrfs_del_delalloc_inode(struct btrfs_root *root, 1748 struct btrfs_inode *inode) 1749 { 1750 struct btrfs_fs_info *fs_info = root->fs_info; 1751 1752 if (!list_empty(&inode->delalloc_inodes)) { 1753 list_del_init(&inode->delalloc_inodes); 1754 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1755 &inode->runtime_flags); 1756 root->nr_delalloc_inodes--; 1757 if (!root->nr_delalloc_inodes) { 1758 ASSERT(list_empty(&root->delalloc_inodes)); 1759 spin_lock(&fs_info->delalloc_root_lock); 1760 BUG_ON(list_empty(&root->delalloc_root)); 1761 list_del_init(&root->delalloc_root); 1762 spin_unlock(&fs_info->delalloc_root_lock); 1763 } 1764 } 1765 } 1766 1767 static void btrfs_del_delalloc_inode(struct btrfs_root *root, 1768 struct btrfs_inode *inode) 1769 { 1770 spin_lock(&root->delalloc_lock); 1771 __btrfs_del_delalloc_inode(root, inode); 1772 spin_unlock(&root->delalloc_lock); 1773 } 1774 1775 /* 1776 * extent_io.c set_bit_hook, used to track delayed allocation 1777 * bytes in this file, and to maintain the list of inodes that 1778 * have pending delalloc work to be done. 1779 */ 1780 static void btrfs_set_bit_hook(void *private_data, 1781 struct extent_state *state, unsigned *bits) 1782 { 1783 struct inode *inode = private_data; 1784 1785 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1786 1787 if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC)) 1788 WARN_ON(1); 1789 /* 1790 * set_bit and clear bit hooks normally require _irqsave/restore 1791 * but in this case, we are only testing for the DELALLOC 1792 * bit, which is only set or cleared with irqs on 1793 */ 1794 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { 1795 struct btrfs_root *root = BTRFS_I(inode)->root; 1796 u64 len = state->end + 1 - state->start; 1797 u32 num_extents = count_max_extents(len); 1798 bool do_list = !btrfs_is_free_space_inode(BTRFS_I(inode)); 1799 1800 spin_lock(&BTRFS_I(inode)->lock); 1801 btrfs_mod_outstanding_extents(BTRFS_I(inode), num_extents); 1802 spin_unlock(&BTRFS_I(inode)->lock); 1803 1804 /* For sanity tests */ 1805 if (btrfs_is_testing(fs_info)) 1806 return; 1807 1808 percpu_counter_add_batch(&fs_info->delalloc_bytes, len, 1809 fs_info->delalloc_batch); 1810 spin_lock(&BTRFS_I(inode)->lock); 1811 BTRFS_I(inode)->delalloc_bytes += len; 1812 if (*bits & EXTENT_DEFRAG) 1813 BTRFS_I(inode)->defrag_bytes += len; 1814 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1815 &BTRFS_I(inode)->runtime_flags)) 1816 btrfs_add_delalloc_inodes(root, inode); 1817 spin_unlock(&BTRFS_I(inode)->lock); 1818 } 1819 1820 if (!(state->state & EXTENT_DELALLOC_NEW) && 1821 (*bits & EXTENT_DELALLOC_NEW)) { 1822 spin_lock(&BTRFS_I(inode)->lock); 1823 BTRFS_I(inode)->new_delalloc_bytes += state->end + 1 - 1824 state->start; 1825 spin_unlock(&BTRFS_I(inode)->lock); 1826 } 1827 } 1828 1829 /* 1830 * extent_io.c clear_bit_hook, see set_bit_hook for why 1831 */ 1832 static void btrfs_clear_bit_hook(void *private_data, 1833 struct extent_state *state, 1834 unsigned *bits) 1835 { 1836 struct btrfs_inode *inode = BTRFS_I((struct inode *)private_data); 1837 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb); 1838 u64 len = state->end + 1 - state->start; 1839 u32 num_extents = count_max_extents(len); 1840 1841 if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) { 1842 spin_lock(&inode->lock); 1843 inode->defrag_bytes -= len; 1844 spin_unlock(&inode->lock); 1845 } 1846 1847 /* 1848 * set_bit and clear bit hooks normally require _irqsave/restore 1849 * but in this case, we are only testing for the DELALLOC 1850 * bit, which is only set or cleared with irqs on 1851 */ 1852 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { 1853 struct btrfs_root *root = inode->root; 1854 bool do_list = !btrfs_is_free_space_inode(inode); 1855 1856 spin_lock(&inode->lock); 1857 btrfs_mod_outstanding_extents(inode, -num_extents); 1858 spin_unlock(&inode->lock); 1859 1860 /* 1861 * We don't reserve metadata space for space cache inodes so we 1862 * don't need to call dellalloc_release_metadata if there is an 1863 * error. 1864 */ 1865 if (*bits & EXTENT_CLEAR_META_RESV && 1866 root != fs_info->tree_root) 1867 btrfs_delalloc_release_metadata(inode, len, false); 1868 1869 /* For sanity tests. */ 1870 if (btrfs_is_testing(fs_info)) 1871 return; 1872 1873 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID && 1874 do_list && !(state->state & EXTENT_NORESERVE) && 1875 (*bits & EXTENT_CLEAR_DATA_RESV)) 1876 btrfs_free_reserved_data_space_noquota( 1877 &inode->vfs_inode, 1878 state->start, len); 1879 1880 percpu_counter_add_batch(&fs_info->delalloc_bytes, -len, 1881 fs_info->delalloc_batch); 1882 spin_lock(&inode->lock); 1883 inode->delalloc_bytes -= len; 1884 if (do_list && inode->delalloc_bytes == 0 && 1885 test_bit(BTRFS_INODE_IN_DELALLOC_LIST, 1886 &inode->runtime_flags)) 1887 btrfs_del_delalloc_inode(root, inode); 1888 spin_unlock(&inode->lock); 1889 } 1890 1891 if ((state->state & EXTENT_DELALLOC_NEW) && 1892 (*bits & EXTENT_DELALLOC_NEW)) { 1893 spin_lock(&inode->lock); 1894 ASSERT(inode->new_delalloc_bytes >= len); 1895 inode->new_delalloc_bytes -= len; 1896 spin_unlock(&inode->lock); 1897 } 1898 } 1899 1900 /* 1901 * Merge bio hook, this must check the chunk tree to make sure we don't create 1902 * bios that span stripes or chunks 1903 * 1904 * return 1 if page cannot be merged to bio 1905 * return 0 if page can be merged to bio 1906 * return error otherwise 1907 */ 1908 int btrfs_merge_bio_hook(struct page *page, unsigned long offset, 1909 size_t size, struct bio *bio, 1910 unsigned long bio_flags) 1911 { 1912 struct inode *inode = page->mapping->host; 1913 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1914 u64 logical = (u64)bio->bi_iter.bi_sector << 9; 1915 u64 length = 0; 1916 u64 map_length; 1917 int ret; 1918 1919 if (bio_flags & EXTENT_BIO_COMPRESSED) 1920 return 0; 1921 1922 length = bio->bi_iter.bi_size; 1923 map_length = length; 1924 ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length, 1925 NULL, 0); 1926 if (ret < 0) 1927 return ret; 1928 if (map_length < length + size) 1929 return 1; 1930 return 0; 1931 } 1932 1933 /* 1934 * in order to insert checksums into the metadata in large chunks, 1935 * we wait until bio submission time. All the pages in the bio are 1936 * checksummed and sums are attached onto the ordered extent record. 1937 * 1938 * At IO completion time the cums attached on the ordered extent record 1939 * are inserted into the btree 1940 */ 1941 static blk_status_t btrfs_submit_bio_start(void *private_data, struct bio *bio, 1942 u64 bio_offset) 1943 { 1944 struct inode *inode = private_data; 1945 blk_status_t ret = 0; 1946 1947 ret = btrfs_csum_one_bio(inode, bio, 0, 0); 1948 BUG_ON(ret); /* -ENOMEM */ 1949 return 0; 1950 } 1951 1952 /* 1953 * in order to insert checksums into the metadata in large chunks, 1954 * we wait until bio submission time. All the pages in the bio are 1955 * checksummed and sums are attached onto the ordered extent record. 1956 * 1957 * At IO completion time the cums attached on the ordered extent record 1958 * are inserted into the btree 1959 */ 1960 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio, 1961 int mirror_num) 1962 { 1963 struct inode *inode = private_data; 1964 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1965 blk_status_t ret; 1966 1967 ret = btrfs_map_bio(fs_info, bio, mirror_num, 1); 1968 if (ret) { 1969 bio->bi_status = ret; 1970 bio_endio(bio); 1971 } 1972 return ret; 1973 } 1974 1975 /* 1976 * extent_io.c submission hook. This does the right thing for csum calculation 1977 * on write, or reading the csums from the tree before a read. 1978 * 1979 * Rules about async/sync submit, 1980 * a) read: sync submit 1981 * 1982 * b) write without checksum: sync submit 1983 * 1984 * c) write with checksum: 1985 * c-1) if bio is issued by fsync: sync submit 1986 * (sync_writers != 0) 1987 * 1988 * c-2) if root is reloc root: sync submit 1989 * (only in case of buffered IO) 1990 * 1991 * c-3) otherwise: async submit 1992 */ 1993 static blk_status_t btrfs_submit_bio_hook(void *private_data, struct bio *bio, 1994 int mirror_num, unsigned long bio_flags, 1995 u64 bio_offset) 1996 { 1997 struct inode *inode = private_data; 1998 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 1999 struct btrfs_root *root = BTRFS_I(inode)->root; 2000 enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA; 2001 blk_status_t ret = 0; 2002 int skip_sum; 2003 int async = !atomic_read(&BTRFS_I(inode)->sync_writers); 2004 2005 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 2006 2007 if (btrfs_is_free_space_inode(BTRFS_I(inode))) 2008 metadata = BTRFS_WQ_ENDIO_FREE_SPACE; 2009 2010 if (bio_op(bio) != REQ_OP_WRITE) { 2011 ret = btrfs_bio_wq_end_io(fs_info, bio, metadata); 2012 if (ret) 2013 goto out; 2014 2015 if (bio_flags & EXTENT_BIO_COMPRESSED) { 2016 ret = btrfs_submit_compressed_read(inode, bio, 2017 mirror_num, 2018 bio_flags); 2019 goto out; 2020 } else if (!skip_sum) { 2021 ret = btrfs_lookup_bio_sums(inode, bio, NULL); 2022 if (ret) 2023 goto out; 2024 } 2025 goto mapit; 2026 } else if (async && !skip_sum) { 2027 /* csum items have already been cloned */ 2028 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) 2029 goto mapit; 2030 /* we're doing a write, do the async checksumming */ 2031 ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, bio_flags, 2032 bio_offset, inode, 2033 btrfs_submit_bio_start); 2034 goto out; 2035 } else if (!skip_sum) { 2036 ret = btrfs_csum_one_bio(inode, bio, 0, 0); 2037 if (ret) 2038 goto out; 2039 } 2040 2041 mapit: 2042 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0); 2043 2044 out: 2045 if (ret) { 2046 bio->bi_status = ret; 2047 bio_endio(bio); 2048 } 2049 return ret; 2050 } 2051 2052 /* 2053 * given a list of ordered sums record them in the inode. This happens 2054 * at IO completion time based on sums calculated at bio submission time. 2055 */ 2056 static noinline int add_pending_csums(struct btrfs_trans_handle *trans, 2057 struct inode *inode, struct list_head *list) 2058 { 2059 struct btrfs_ordered_sum *sum; 2060 int ret; 2061 2062 list_for_each_entry(sum, list, list) { 2063 trans->adding_csums = true; 2064 ret = btrfs_csum_file_blocks(trans, 2065 BTRFS_I(inode)->root->fs_info->csum_root, sum); 2066 trans->adding_csums = false; 2067 if (ret) 2068 return ret; 2069 } 2070 return 0; 2071 } 2072 2073 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, 2074 unsigned int extra_bits, 2075 struct extent_state **cached_state, int dedupe) 2076 { 2077 WARN_ON((end & (PAGE_SIZE - 1)) == 0); 2078 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end, 2079 extra_bits, cached_state); 2080 } 2081 2082 /* see btrfs_writepage_start_hook for details on why this is required */ 2083 struct btrfs_writepage_fixup { 2084 struct page *page; 2085 struct btrfs_work work; 2086 }; 2087 2088 static void btrfs_writepage_fixup_worker(struct btrfs_work *work) 2089 { 2090 struct btrfs_writepage_fixup *fixup; 2091 struct btrfs_ordered_extent *ordered; 2092 struct extent_state *cached_state = NULL; 2093 struct extent_changeset *data_reserved = NULL; 2094 struct page *page; 2095 struct inode *inode; 2096 u64 page_start; 2097 u64 page_end; 2098 int ret; 2099 2100 fixup = container_of(work, struct btrfs_writepage_fixup, work); 2101 page = fixup->page; 2102 again: 2103 lock_page(page); 2104 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { 2105 ClearPageChecked(page); 2106 goto out_page; 2107 } 2108 2109 inode = page->mapping->host; 2110 page_start = page_offset(page); 2111 page_end = page_offset(page) + PAGE_SIZE - 1; 2112 2113 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 2114 &cached_state); 2115 2116 /* already ordered? We're done */ 2117 if (PagePrivate2(page)) 2118 goto out; 2119 2120 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start, 2121 PAGE_SIZE); 2122 if (ordered) { 2123 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, 2124 page_end, &cached_state); 2125 unlock_page(page); 2126 btrfs_start_ordered_extent(inode, ordered, 1); 2127 btrfs_put_ordered_extent(ordered); 2128 goto again; 2129 } 2130 2131 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, 2132 PAGE_SIZE); 2133 if (ret) { 2134 mapping_set_error(page->mapping, ret); 2135 end_extent_writepage(page, ret, page_start, page_end); 2136 ClearPageChecked(page); 2137 goto out; 2138 } 2139 2140 ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, 2141 &cached_state, 0); 2142 if (ret) { 2143 mapping_set_error(page->mapping, ret); 2144 end_extent_writepage(page, ret, page_start, page_end); 2145 ClearPageChecked(page); 2146 goto out; 2147 } 2148 2149 ClearPageChecked(page); 2150 set_page_dirty(page); 2151 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, false); 2152 out: 2153 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, 2154 &cached_state); 2155 out_page: 2156 unlock_page(page); 2157 put_page(page); 2158 kfree(fixup); 2159 extent_changeset_free(data_reserved); 2160 } 2161 2162 /* 2163 * There are a few paths in the higher layers of the kernel that directly 2164 * set the page dirty bit without asking the filesystem if it is a 2165 * good idea. This causes problems because we want to make sure COW 2166 * properly happens and the data=ordered rules are followed. 2167 * 2168 * In our case any range that doesn't have the ORDERED bit set 2169 * hasn't been properly setup for IO. We kick off an async process 2170 * to fix it up. The async helper will wait for ordered extents, set 2171 * the delalloc bit and make it safe to write the page. 2172 */ 2173 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) 2174 { 2175 struct inode *inode = page->mapping->host; 2176 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2177 struct btrfs_writepage_fixup *fixup; 2178 2179 /* this page is properly in the ordered list */ 2180 if (TestClearPagePrivate2(page)) 2181 return 0; 2182 2183 if (PageChecked(page)) 2184 return -EAGAIN; 2185 2186 fixup = kzalloc(sizeof(*fixup), GFP_NOFS); 2187 if (!fixup) 2188 return -EAGAIN; 2189 2190 SetPageChecked(page); 2191 get_page(page); 2192 btrfs_init_work(&fixup->work, btrfs_fixup_helper, 2193 btrfs_writepage_fixup_worker, NULL, NULL); 2194 fixup->page = page; 2195 btrfs_queue_work(fs_info->fixup_workers, &fixup->work); 2196 return -EBUSY; 2197 } 2198 2199 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, 2200 struct inode *inode, u64 file_pos, 2201 u64 disk_bytenr, u64 disk_num_bytes, 2202 u64 num_bytes, u64 ram_bytes, 2203 u8 compression, u8 encryption, 2204 u16 other_encoding, int extent_type) 2205 { 2206 struct btrfs_root *root = BTRFS_I(inode)->root; 2207 struct btrfs_file_extent_item *fi; 2208 struct btrfs_path *path; 2209 struct extent_buffer *leaf; 2210 struct btrfs_key ins; 2211 u64 qg_released; 2212 int extent_inserted = 0; 2213 int ret; 2214 2215 path = btrfs_alloc_path(); 2216 if (!path) 2217 return -ENOMEM; 2218 2219 /* 2220 * we may be replacing one extent in the tree with another. 2221 * The new extent is pinned in the extent map, and we don't want 2222 * to drop it from the cache until it is completely in the btree. 2223 * 2224 * So, tell btrfs_drop_extents to leave this extent in the cache. 2225 * the caller is expected to unpin it and allow it to be merged 2226 * with the others. 2227 */ 2228 ret = __btrfs_drop_extents(trans, root, inode, path, file_pos, 2229 file_pos + num_bytes, NULL, 0, 2230 1, sizeof(*fi), &extent_inserted); 2231 if (ret) 2232 goto out; 2233 2234 if (!extent_inserted) { 2235 ins.objectid = btrfs_ino(BTRFS_I(inode)); 2236 ins.offset = file_pos; 2237 ins.type = BTRFS_EXTENT_DATA_KEY; 2238 2239 path->leave_spinning = 1; 2240 ret = btrfs_insert_empty_item(trans, root, path, &ins, 2241 sizeof(*fi)); 2242 if (ret) 2243 goto out; 2244 } 2245 leaf = path->nodes[0]; 2246 fi = btrfs_item_ptr(leaf, path->slots[0], 2247 struct btrfs_file_extent_item); 2248 btrfs_set_file_extent_generation(leaf, fi, trans->transid); 2249 btrfs_set_file_extent_type(leaf, fi, extent_type); 2250 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); 2251 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes); 2252 btrfs_set_file_extent_offset(leaf, fi, 0); 2253 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); 2254 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes); 2255 btrfs_set_file_extent_compression(leaf, fi, compression); 2256 btrfs_set_file_extent_encryption(leaf, fi, encryption); 2257 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding); 2258 2259 btrfs_mark_buffer_dirty(leaf); 2260 btrfs_release_path(path); 2261 2262 inode_add_bytes(inode, num_bytes); 2263 2264 ins.objectid = disk_bytenr; 2265 ins.offset = disk_num_bytes; 2266 ins.type = BTRFS_EXTENT_ITEM_KEY; 2267 2268 /* 2269 * Release the reserved range from inode dirty range map, as it is 2270 * already moved into delayed_ref_head 2271 */ 2272 ret = btrfs_qgroup_release_data(inode, file_pos, ram_bytes); 2273 if (ret < 0) 2274 goto out; 2275 qg_released = ret; 2276 ret = btrfs_alloc_reserved_file_extent(trans, root, 2277 btrfs_ino(BTRFS_I(inode)), 2278 file_pos, qg_released, &ins); 2279 out: 2280 btrfs_free_path(path); 2281 2282 return ret; 2283 } 2284 2285 /* snapshot-aware defrag */ 2286 struct sa_defrag_extent_backref { 2287 struct rb_node node; 2288 struct old_sa_defrag_extent *old; 2289 u64 root_id; 2290 u64 inum; 2291 u64 file_pos; 2292 u64 extent_offset; 2293 u64 num_bytes; 2294 u64 generation; 2295 }; 2296 2297 struct old_sa_defrag_extent { 2298 struct list_head list; 2299 struct new_sa_defrag_extent *new; 2300 2301 u64 extent_offset; 2302 u64 bytenr; 2303 u64 offset; 2304 u64 len; 2305 int count; 2306 }; 2307 2308 struct new_sa_defrag_extent { 2309 struct rb_root root; 2310 struct list_head head; 2311 struct btrfs_path *path; 2312 struct inode *inode; 2313 u64 file_pos; 2314 u64 len; 2315 u64 bytenr; 2316 u64 disk_len; 2317 u8 compress_type; 2318 }; 2319 2320 static int backref_comp(struct sa_defrag_extent_backref *b1, 2321 struct sa_defrag_extent_backref *b2) 2322 { 2323 if (b1->root_id < b2->root_id) 2324 return -1; 2325 else if (b1->root_id > b2->root_id) 2326 return 1; 2327 2328 if (b1->inum < b2->inum) 2329 return -1; 2330 else if (b1->inum > b2->inum) 2331 return 1; 2332 2333 if (b1->file_pos < b2->file_pos) 2334 return -1; 2335 else if (b1->file_pos > b2->file_pos) 2336 return 1; 2337 2338 /* 2339 * [------------------------------] ===> (a range of space) 2340 * |<--->| |<---->| =============> (fs/file tree A) 2341 * |<---------------------------->| ===> (fs/file tree B) 2342 * 2343 * A range of space can refer to two file extents in one tree while 2344 * refer to only one file extent in another tree. 2345 * 2346 * So we may process a disk offset more than one time(two extents in A) 2347 * and locate at the same extent(one extent in B), then insert two same 2348 * backrefs(both refer to the extent in B). 2349 */ 2350 return 0; 2351 } 2352 2353 static void backref_insert(struct rb_root *root, 2354 struct sa_defrag_extent_backref *backref) 2355 { 2356 struct rb_node **p = &root->rb_node; 2357 struct rb_node *parent = NULL; 2358 struct sa_defrag_extent_backref *entry; 2359 int ret; 2360 2361 while (*p) { 2362 parent = *p; 2363 entry = rb_entry(parent, struct sa_defrag_extent_backref, node); 2364 2365 ret = backref_comp(backref, entry); 2366 if (ret < 0) 2367 p = &(*p)->rb_left; 2368 else 2369 p = &(*p)->rb_right; 2370 } 2371 2372 rb_link_node(&backref->node, parent, p); 2373 rb_insert_color(&backref->node, root); 2374 } 2375 2376 /* 2377 * Note the backref might has changed, and in this case we just return 0. 2378 */ 2379 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id, 2380 void *ctx) 2381 { 2382 struct btrfs_file_extent_item *extent; 2383 struct old_sa_defrag_extent *old = ctx; 2384 struct new_sa_defrag_extent *new = old->new; 2385 struct btrfs_path *path = new->path; 2386 struct btrfs_key key; 2387 struct btrfs_root *root; 2388 struct sa_defrag_extent_backref *backref; 2389 struct extent_buffer *leaf; 2390 struct inode *inode = new->inode; 2391 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2392 int slot; 2393 int ret; 2394 u64 extent_offset; 2395 u64 num_bytes; 2396 2397 if (BTRFS_I(inode)->root->root_key.objectid == root_id && 2398 inum == btrfs_ino(BTRFS_I(inode))) 2399 return 0; 2400 2401 key.objectid = root_id; 2402 key.type = BTRFS_ROOT_ITEM_KEY; 2403 key.offset = (u64)-1; 2404 2405 root = btrfs_read_fs_root_no_name(fs_info, &key); 2406 if (IS_ERR(root)) { 2407 if (PTR_ERR(root) == -ENOENT) 2408 return 0; 2409 WARN_ON(1); 2410 btrfs_debug(fs_info, "inum=%llu, offset=%llu, root_id=%llu", 2411 inum, offset, root_id); 2412 return PTR_ERR(root); 2413 } 2414 2415 key.objectid = inum; 2416 key.type = BTRFS_EXTENT_DATA_KEY; 2417 if (offset > (u64)-1 << 32) 2418 key.offset = 0; 2419 else 2420 key.offset = offset; 2421 2422 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2423 if (WARN_ON(ret < 0)) 2424 return ret; 2425 ret = 0; 2426 2427 while (1) { 2428 cond_resched(); 2429 2430 leaf = path->nodes[0]; 2431 slot = path->slots[0]; 2432 2433 if (slot >= btrfs_header_nritems(leaf)) { 2434 ret = btrfs_next_leaf(root, path); 2435 if (ret < 0) { 2436 goto out; 2437 } else if (ret > 0) { 2438 ret = 0; 2439 goto out; 2440 } 2441 continue; 2442 } 2443 2444 path->slots[0]++; 2445 2446 btrfs_item_key_to_cpu(leaf, &key, slot); 2447 2448 if (key.objectid > inum) 2449 goto out; 2450 2451 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY) 2452 continue; 2453 2454 extent = btrfs_item_ptr(leaf, slot, 2455 struct btrfs_file_extent_item); 2456 2457 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr) 2458 continue; 2459 2460 /* 2461 * 'offset' refers to the exact key.offset, 2462 * NOT the 'offset' field in btrfs_extent_data_ref, ie. 2463 * (key.offset - extent_offset). 2464 */ 2465 if (key.offset != offset) 2466 continue; 2467 2468 extent_offset = btrfs_file_extent_offset(leaf, extent); 2469 num_bytes = btrfs_file_extent_num_bytes(leaf, extent); 2470 2471 if (extent_offset >= old->extent_offset + old->offset + 2472 old->len || extent_offset + num_bytes <= 2473 old->extent_offset + old->offset) 2474 continue; 2475 break; 2476 } 2477 2478 backref = kmalloc(sizeof(*backref), GFP_NOFS); 2479 if (!backref) { 2480 ret = -ENOENT; 2481 goto out; 2482 } 2483 2484 backref->root_id = root_id; 2485 backref->inum = inum; 2486 backref->file_pos = offset; 2487 backref->num_bytes = num_bytes; 2488 backref->extent_offset = extent_offset; 2489 backref->generation = btrfs_file_extent_generation(leaf, extent); 2490 backref->old = old; 2491 backref_insert(&new->root, backref); 2492 old->count++; 2493 out: 2494 btrfs_release_path(path); 2495 WARN_ON(ret); 2496 return ret; 2497 } 2498 2499 static noinline bool record_extent_backrefs(struct btrfs_path *path, 2500 struct new_sa_defrag_extent *new) 2501 { 2502 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); 2503 struct old_sa_defrag_extent *old, *tmp; 2504 int ret; 2505 2506 new->path = path; 2507 2508 list_for_each_entry_safe(old, tmp, &new->head, list) { 2509 ret = iterate_inodes_from_logical(old->bytenr + 2510 old->extent_offset, fs_info, 2511 path, record_one_backref, 2512 old, false); 2513 if (ret < 0 && ret != -ENOENT) 2514 return false; 2515 2516 /* no backref to be processed for this extent */ 2517 if (!old->count) { 2518 list_del(&old->list); 2519 kfree(old); 2520 } 2521 } 2522 2523 if (list_empty(&new->head)) 2524 return false; 2525 2526 return true; 2527 } 2528 2529 static int relink_is_mergable(struct extent_buffer *leaf, 2530 struct btrfs_file_extent_item *fi, 2531 struct new_sa_defrag_extent *new) 2532 { 2533 if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr) 2534 return 0; 2535 2536 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) 2537 return 0; 2538 2539 if (btrfs_file_extent_compression(leaf, fi) != new->compress_type) 2540 return 0; 2541 2542 if (btrfs_file_extent_encryption(leaf, fi) || 2543 btrfs_file_extent_other_encoding(leaf, fi)) 2544 return 0; 2545 2546 return 1; 2547 } 2548 2549 /* 2550 * Note the backref might has changed, and in this case we just return 0. 2551 */ 2552 static noinline int relink_extent_backref(struct btrfs_path *path, 2553 struct sa_defrag_extent_backref *prev, 2554 struct sa_defrag_extent_backref *backref) 2555 { 2556 struct btrfs_file_extent_item *extent; 2557 struct btrfs_file_extent_item *item; 2558 struct btrfs_ordered_extent *ordered; 2559 struct btrfs_trans_handle *trans; 2560 struct btrfs_root *root; 2561 struct btrfs_key key; 2562 struct extent_buffer *leaf; 2563 struct old_sa_defrag_extent *old = backref->old; 2564 struct new_sa_defrag_extent *new = old->new; 2565 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); 2566 struct inode *inode; 2567 struct extent_state *cached = NULL; 2568 int ret = 0; 2569 u64 start; 2570 u64 len; 2571 u64 lock_start; 2572 u64 lock_end; 2573 bool merge = false; 2574 int index; 2575 2576 if (prev && prev->root_id == backref->root_id && 2577 prev->inum == backref->inum && 2578 prev->file_pos + prev->num_bytes == backref->file_pos) 2579 merge = true; 2580 2581 /* step 1: get root */ 2582 key.objectid = backref->root_id; 2583 key.type = BTRFS_ROOT_ITEM_KEY; 2584 key.offset = (u64)-1; 2585 2586 index = srcu_read_lock(&fs_info->subvol_srcu); 2587 2588 root = btrfs_read_fs_root_no_name(fs_info, &key); 2589 if (IS_ERR(root)) { 2590 srcu_read_unlock(&fs_info->subvol_srcu, index); 2591 if (PTR_ERR(root) == -ENOENT) 2592 return 0; 2593 return PTR_ERR(root); 2594 } 2595 2596 if (btrfs_root_readonly(root)) { 2597 srcu_read_unlock(&fs_info->subvol_srcu, index); 2598 return 0; 2599 } 2600 2601 /* step 2: get inode */ 2602 key.objectid = backref->inum; 2603 key.type = BTRFS_INODE_ITEM_KEY; 2604 key.offset = 0; 2605 2606 inode = btrfs_iget(fs_info->sb, &key, root, NULL); 2607 if (IS_ERR(inode)) { 2608 srcu_read_unlock(&fs_info->subvol_srcu, index); 2609 return 0; 2610 } 2611 2612 srcu_read_unlock(&fs_info->subvol_srcu, index); 2613 2614 /* step 3: relink backref */ 2615 lock_start = backref->file_pos; 2616 lock_end = backref->file_pos + backref->num_bytes - 1; 2617 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end, 2618 &cached); 2619 2620 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end); 2621 if (ordered) { 2622 btrfs_put_ordered_extent(ordered); 2623 goto out_unlock; 2624 } 2625 2626 trans = btrfs_join_transaction(root); 2627 if (IS_ERR(trans)) { 2628 ret = PTR_ERR(trans); 2629 goto out_unlock; 2630 } 2631 2632 key.objectid = backref->inum; 2633 key.type = BTRFS_EXTENT_DATA_KEY; 2634 key.offset = backref->file_pos; 2635 2636 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2637 if (ret < 0) { 2638 goto out_free_path; 2639 } else if (ret > 0) { 2640 ret = 0; 2641 goto out_free_path; 2642 } 2643 2644 extent = btrfs_item_ptr(path->nodes[0], path->slots[0], 2645 struct btrfs_file_extent_item); 2646 2647 if (btrfs_file_extent_generation(path->nodes[0], extent) != 2648 backref->generation) 2649 goto out_free_path; 2650 2651 btrfs_release_path(path); 2652 2653 start = backref->file_pos; 2654 if (backref->extent_offset < old->extent_offset + old->offset) 2655 start += old->extent_offset + old->offset - 2656 backref->extent_offset; 2657 2658 len = min(backref->extent_offset + backref->num_bytes, 2659 old->extent_offset + old->offset + old->len); 2660 len -= max(backref->extent_offset, old->extent_offset + old->offset); 2661 2662 ret = btrfs_drop_extents(trans, root, inode, start, 2663 start + len, 1); 2664 if (ret) 2665 goto out_free_path; 2666 again: 2667 key.objectid = btrfs_ino(BTRFS_I(inode)); 2668 key.type = BTRFS_EXTENT_DATA_KEY; 2669 key.offset = start; 2670 2671 path->leave_spinning = 1; 2672 if (merge) { 2673 struct btrfs_file_extent_item *fi; 2674 u64 extent_len; 2675 struct btrfs_key found_key; 2676 2677 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2678 if (ret < 0) 2679 goto out_free_path; 2680 2681 path->slots[0]--; 2682 leaf = path->nodes[0]; 2683 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2684 2685 fi = btrfs_item_ptr(leaf, path->slots[0], 2686 struct btrfs_file_extent_item); 2687 extent_len = btrfs_file_extent_num_bytes(leaf, fi); 2688 2689 if (extent_len + found_key.offset == start && 2690 relink_is_mergable(leaf, fi, new)) { 2691 btrfs_set_file_extent_num_bytes(leaf, fi, 2692 extent_len + len); 2693 btrfs_mark_buffer_dirty(leaf); 2694 inode_add_bytes(inode, len); 2695 2696 ret = 1; 2697 goto out_free_path; 2698 } else { 2699 merge = false; 2700 btrfs_release_path(path); 2701 goto again; 2702 } 2703 } 2704 2705 ret = btrfs_insert_empty_item(trans, root, path, &key, 2706 sizeof(*extent)); 2707 if (ret) { 2708 btrfs_abort_transaction(trans, ret); 2709 goto out_free_path; 2710 } 2711 2712 leaf = path->nodes[0]; 2713 item = btrfs_item_ptr(leaf, path->slots[0], 2714 struct btrfs_file_extent_item); 2715 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr); 2716 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len); 2717 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos); 2718 btrfs_set_file_extent_num_bytes(leaf, item, len); 2719 btrfs_set_file_extent_ram_bytes(leaf, item, new->len); 2720 btrfs_set_file_extent_generation(leaf, item, trans->transid); 2721 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG); 2722 btrfs_set_file_extent_compression(leaf, item, new->compress_type); 2723 btrfs_set_file_extent_encryption(leaf, item, 0); 2724 btrfs_set_file_extent_other_encoding(leaf, item, 0); 2725 2726 btrfs_mark_buffer_dirty(leaf); 2727 inode_add_bytes(inode, len); 2728 btrfs_release_path(path); 2729 2730 ret = btrfs_inc_extent_ref(trans, root, new->bytenr, 2731 new->disk_len, 0, 2732 backref->root_id, backref->inum, 2733 new->file_pos); /* start - extent_offset */ 2734 if (ret) { 2735 btrfs_abort_transaction(trans, ret); 2736 goto out_free_path; 2737 } 2738 2739 ret = 1; 2740 out_free_path: 2741 btrfs_release_path(path); 2742 path->leave_spinning = 0; 2743 btrfs_end_transaction(trans); 2744 out_unlock: 2745 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end, 2746 &cached); 2747 iput(inode); 2748 return ret; 2749 } 2750 2751 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new) 2752 { 2753 struct old_sa_defrag_extent *old, *tmp; 2754 2755 if (!new) 2756 return; 2757 2758 list_for_each_entry_safe(old, tmp, &new->head, list) { 2759 kfree(old); 2760 } 2761 kfree(new); 2762 } 2763 2764 static void relink_file_extents(struct new_sa_defrag_extent *new) 2765 { 2766 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb); 2767 struct btrfs_path *path; 2768 struct sa_defrag_extent_backref *backref; 2769 struct sa_defrag_extent_backref *prev = NULL; 2770 struct inode *inode; 2771 struct rb_node *node; 2772 int ret; 2773 2774 inode = new->inode; 2775 2776 path = btrfs_alloc_path(); 2777 if (!path) 2778 return; 2779 2780 if (!record_extent_backrefs(path, new)) { 2781 btrfs_free_path(path); 2782 goto out; 2783 } 2784 btrfs_release_path(path); 2785 2786 while (1) { 2787 node = rb_first(&new->root); 2788 if (!node) 2789 break; 2790 rb_erase(node, &new->root); 2791 2792 backref = rb_entry(node, struct sa_defrag_extent_backref, node); 2793 2794 ret = relink_extent_backref(path, prev, backref); 2795 WARN_ON(ret < 0); 2796 2797 kfree(prev); 2798 2799 if (ret == 1) 2800 prev = backref; 2801 else 2802 prev = NULL; 2803 cond_resched(); 2804 } 2805 kfree(prev); 2806 2807 btrfs_free_path(path); 2808 out: 2809 free_sa_defrag_extent(new); 2810 2811 atomic_dec(&fs_info->defrag_running); 2812 wake_up(&fs_info->transaction_wait); 2813 } 2814 2815 static struct new_sa_defrag_extent * 2816 record_old_file_extents(struct inode *inode, 2817 struct btrfs_ordered_extent *ordered) 2818 { 2819 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2820 struct btrfs_root *root = BTRFS_I(inode)->root; 2821 struct btrfs_path *path; 2822 struct btrfs_key key; 2823 struct old_sa_defrag_extent *old; 2824 struct new_sa_defrag_extent *new; 2825 int ret; 2826 2827 new = kmalloc(sizeof(*new), GFP_NOFS); 2828 if (!new) 2829 return NULL; 2830 2831 new->inode = inode; 2832 new->file_pos = ordered->file_offset; 2833 new->len = ordered->len; 2834 new->bytenr = ordered->start; 2835 new->disk_len = ordered->disk_len; 2836 new->compress_type = ordered->compress_type; 2837 new->root = RB_ROOT; 2838 INIT_LIST_HEAD(&new->head); 2839 2840 path = btrfs_alloc_path(); 2841 if (!path) 2842 goto out_kfree; 2843 2844 key.objectid = btrfs_ino(BTRFS_I(inode)); 2845 key.type = BTRFS_EXTENT_DATA_KEY; 2846 key.offset = new->file_pos; 2847 2848 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2849 if (ret < 0) 2850 goto out_free_path; 2851 if (ret > 0 && path->slots[0] > 0) 2852 path->slots[0]--; 2853 2854 /* find out all the old extents for the file range */ 2855 while (1) { 2856 struct btrfs_file_extent_item *extent; 2857 struct extent_buffer *l; 2858 int slot; 2859 u64 num_bytes; 2860 u64 offset; 2861 u64 end; 2862 u64 disk_bytenr; 2863 u64 extent_offset; 2864 2865 l = path->nodes[0]; 2866 slot = path->slots[0]; 2867 2868 if (slot >= btrfs_header_nritems(l)) { 2869 ret = btrfs_next_leaf(root, path); 2870 if (ret < 0) 2871 goto out_free_path; 2872 else if (ret > 0) 2873 break; 2874 continue; 2875 } 2876 2877 btrfs_item_key_to_cpu(l, &key, slot); 2878 2879 if (key.objectid != btrfs_ino(BTRFS_I(inode))) 2880 break; 2881 if (key.type != BTRFS_EXTENT_DATA_KEY) 2882 break; 2883 if (key.offset >= new->file_pos + new->len) 2884 break; 2885 2886 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item); 2887 2888 num_bytes = btrfs_file_extent_num_bytes(l, extent); 2889 if (key.offset + num_bytes < new->file_pos) 2890 goto next; 2891 2892 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent); 2893 if (!disk_bytenr) 2894 goto next; 2895 2896 extent_offset = btrfs_file_extent_offset(l, extent); 2897 2898 old = kmalloc(sizeof(*old), GFP_NOFS); 2899 if (!old) 2900 goto out_free_path; 2901 2902 offset = max(new->file_pos, key.offset); 2903 end = min(new->file_pos + new->len, key.offset + num_bytes); 2904 2905 old->bytenr = disk_bytenr; 2906 old->extent_offset = extent_offset; 2907 old->offset = offset - key.offset; 2908 old->len = end - offset; 2909 old->new = new; 2910 old->count = 0; 2911 list_add_tail(&old->list, &new->head); 2912 next: 2913 path->slots[0]++; 2914 cond_resched(); 2915 } 2916 2917 btrfs_free_path(path); 2918 atomic_inc(&fs_info->defrag_running); 2919 2920 return new; 2921 2922 out_free_path: 2923 btrfs_free_path(path); 2924 out_kfree: 2925 free_sa_defrag_extent(new); 2926 return NULL; 2927 } 2928 2929 static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info, 2930 u64 start, u64 len) 2931 { 2932 struct btrfs_block_group_cache *cache; 2933 2934 cache = btrfs_lookup_block_group(fs_info, start); 2935 ASSERT(cache); 2936 2937 spin_lock(&cache->lock); 2938 cache->delalloc_bytes -= len; 2939 spin_unlock(&cache->lock); 2940 2941 btrfs_put_block_group(cache); 2942 } 2943 2944 /* as ordered data IO finishes, this gets called so we can finish 2945 * an ordered extent if the range of bytes in the file it covers are 2946 * fully written. 2947 */ 2948 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent) 2949 { 2950 struct inode *inode = ordered_extent->inode; 2951 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 2952 struct btrfs_root *root = BTRFS_I(inode)->root; 2953 struct btrfs_trans_handle *trans = NULL; 2954 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 2955 struct extent_state *cached_state = NULL; 2956 struct new_sa_defrag_extent *new = NULL; 2957 int compress_type = 0; 2958 int ret = 0; 2959 u64 logical_len = ordered_extent->len; 2960 bool nolock; 2961 bool truncated = false; 2962 bool range_locked = false; 2963 bool clear_new_delalloc_bytes = false; 2964 2965 if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && 2966 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) && 2967 !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags)) 2968 clear_new_delalloc_bytes = true; 2969 2970 nolock = btrfs_is_free_space_inode(BTRFS_I(inode)); 2971 2972 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) { 2973 ret = -EIO; 2974 goto out; 2975 } 2976 2977 btrfs_free_io_failure_record(BTRFS_I(inode), 2978 ordered_extent->file_offset, 2979 ordered_extent->file_offset + 2980 ordered_extent->len - 1); 2981 2982 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) { 2983 truncated = true; 2984 logical_len = ordered_extent->truncated_len; 2985 /* Truncated the entire extent, don't bother adding */ 2986 if (!logical_len) 2987 goto out; 2988 } 2989 2990 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { 2991 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */ 2992 2993 /* 2994 * For mwrite(mmap + memset to write) case, we still reserve 2995 * space for NOCOW range. 2996 * As NOCOW won't cause a new delayed ref, just free the space 2997 */ 2998 btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset, 2999 ordered_extent->len); 3000 btrfs_ordered_update_i_size(inode, 0, ordered_extent); 3001 if (nolock) 3002 trans = btrfs_join_transaction_nolock(root); 3003 else 3004 trans = btrfs_join_transaction(root); 3005 if (IS_ERR(trans)) { 3006 ret = PTR_ERR(trans); 3007 trans = NULL; 3008 goto out; 3009 } 3010 trans->block_rsv = &BTRFS_I(inode)->block_rsv; 3011 ret = btrfs_update_inode_fallback(trans, root, inode); 3012 if (ret) /* -ENOMEM or corruption */ 3013 btrfs_abort_transaction(trans, ret); 3014 goto out; 3015 } 3016 3017 range_locked = true; 3018 lock_extent_bits(io_tree, ordered_extent->file_offset, 3019 ordered_extent->file_offset + ordered_extent->len - 1, 3020 &cached_state); 3021 3022 ret = test_range_bit(io_tree, ordered_extent->file_offset, 3023 ordered_extent->file_offset + ordered_extent->len - 1, 3024 EXTENT_DEFRAG, 0, cached_state); 3025 if (ret) { 3026 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item); 3027 if (0 && last_snapshot >= BTRFS_I(inode)->generation) 3028 /* the inode is shared */ 3029 new = record_old_file_extents(inode, ordered_extent); 3030 3031 clear_extent_bit(io_tree, ordered_extent->file_offset, 3032 ordered_extent->file_offset + ordered_extent->len - 1, 3033 EXTENT_DEFRAG, 0, 0, &cached_state); 3034 } 3035 3036 if (nolock) 3037 trans = btrfs_join_transaction_nolock(root); 3038 else 3039 trans = btrfs_join_transaction(root); 3040 if (IS_ERR(trans)) { 3041 ret = PTR_ERR(trans); 3042 trans = NULL; 3043 goto out; 3044 } 3045 3046 trans->block_rsv = &BTRFS_I(inode)->block_rsv; 3047 3048 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) 3049 compress_type = ordered_extent->compress_type; 3050 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { 3051 BUG_ON(compress_type); 3052 btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset, 3053 ordered_extent->len); 3054 ret = btrfs_mark_extent_written(trans, BTRFS_I(inode), 3055 ordered_extent->file_offset, 3056 ordered_extent->file_offset + 3057 logical_len); 3058 } else { 3059 BUG_ON(root == fs_info->tree_root); 3060 ret = insert_reserved_file_extent(trans, inode, 3061 ordered_extent->file_offset, 3062 ordered_extent->start, 3063 ordered_extent->disk_len, 3064 logical_len, logical_len, 3065 compress_type, 0, 0, 3066 BTRFS_FILE_EXTENT_REG); 3067 if (!ret) 3068 btrfs_release_delalloc_bytes(fs_info, 3069 ordered_extent->start, 3070 ordered_extent->disk_len); 3071 } 3072 unpin_extent_cache(&BTRFS_I(inode)->extent_tree, 3073 ordered_extent->file_offset, ordered_extent->len, 3074 trans->transid); 3075 if (ret < 0) { 3076 btrfs_abort_transaction(trans, ret); 3077 goto out; 3078 } 3079 3080 ret = add_pending_csums(trans, inode, &ordered_extent->list); 3081 if (ret) { 3082 btrfs_abort_transaction(trans, ret); 3083 goto out; 3084 } 3085 3086 btrfs_ordered_update_i_size(inode, 0, ordered_extent); 3087 ret = btrfs_update_inode_fallback(trans, root, inode); 3088 if (ret) { /* -ENOMEM or corruption */ 3089 btrfs_abort_transaction(trans, ret); 3090 goto out; 3091 } 3092 ret = 0; 3093 out: 3094 if (range_locked || clear_new_delalloc_bytes) { 3095 unsigned int clear_bits = 0; 3096 3097 if (range_locked) 3098 clear_bits |= EXTENT_LOCKED; 3099 if (clear_new_delalloc_bytes) 3100 clear_bits |= EXTENT_DELALLOC_NEW; 3101 clear_extent_bit(&BTRFS_I(inode)->io_tree, 3102 ordered_extent->file_offset, 3103 ordered_extent->file_offset + 3104 ordered_extent->len - 1, 3105 clear_bits, 3106 (clear_bits & EXTENT_LOCKED) ? 1 : 0, 3107 0, &cached_state); 3108 } 3109 3110 if (trans) 3111 btrfs_end_transaction(trans); 3112 3113 if (ret || truncated) { 3114 u64 start, end; 3115 3116 if (truncated) 3117 start = ordered_extent->file_offset + logical_len; 3118 else 3119 start = ordered_extent->file_offset; 3120 end = ordered_extent->file_offset + ordered_extent->len - 1; 3121 clear_extent_uptodate(io_tree, start, end, NULL); 3122 3123 /* Drop the cache for the part of the extent we didn't write. */ 3124 btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); 3125 3126 /* 3127 * If the ordered extent had an IOERR or something else went 3128 * wrong we need to return the space for this ordered extent 3129 * back to the allocator. We only free the extent in the 3130 * truncated case if we didn't write out the extent at all. 3131 */ 3132 if ((ret || !logical_len) && 3133 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && 3134 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) 3135 btrfs_free_reserved_extent(fs_info, 3136 ordered_extent->start, 3137 ordered_extent->disk_len, 1); 3138 } 3139 3140 3141 /* 3142 * This needs to be done to make sure anybody waiting knows we are done 3143 * updating everything for this ordered extent. 3144 */ 3145 btrfs_remove_ordered_extent(inode, ordered_extent); 3146 3147 /* for snapshot-aware defrag */ 3148 if (new) { 3149 if (ret) { 3150 free_sa_defrag_extent(new); 3151 atomic_dec(&fs_info->defrag_running); 3152 } else { 3153 relink_file_extents(new); 3154 } 3155 } 3156 3157 /* once for us */ 3158 btrfs_put_ordered_extent(ordered_extent); 3159 /* once for the tree */ 3160 btrfs_put_ordered_extent(ordered_extent); 3161 3162 /* Try to release some metadata so we don't get an OOM but don't wait */ 3163 btrfs_btree_balance_dirty_nodelay(fs_info); 3164 3165 return ret; 3166 } 3167 3168 static void finish_ordered_fn(struct btrfs_work *work) 3169 { 3170 struct btrfs_ordered_extent *ordered_extent; 3171 ordered_extent = container_of(work, struct btrfs_ordered_extent, work); 3172 btrfs_finish_ordered_io(ordered_extent); 3173 } 3174 3175 static void btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, 3176 struct extent_state *state, int uptodate) 3177 { 3178 struct inode *inode = page->mapping->host; 3179 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3180 struct btrfs_ordered_extent *ordered_extent = NULL; 3181 struct btrfs_workqueue *wq; 3182 btrfs_work_func_t func; 3183 3184 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); 3185 3186 ClearPagePrivate2(page); 3187 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start, 3188 end - start + 1, uptodate)) 3189 return; 3190 3191 if (btrfs_is_free_space_inode(BTRFS_I(inode))) { 3192 wq = fs_info->endio_freespace_worker; 3193 func = btrfs_freespace_write_helper; 3194 } else { 3195 wq = fs_info->endio_write_workers; 3196 func = btrfs_endio_write_helper; 3197 } 3198 3199 btrfs_init_work(&ordered_extent->work, func, finish_ordered_fn, NULL, 3200 NULL); 3201 btrfs_queue_work(wq, &ordered_extent->work); 3202 } 3203 3204 static int __readpage_endio_check(struct inode *inode, 3205 struct btrfs_io_bio *io_bio, 3206 int icsum, struct page *page, 3207 int pgoff, u64 start, size_t len) 3208 { 3209 char *kaddr; 3210 u32 csum_expected; 3211 u32 csum = ~(u32)0; 3212 3213 csum_expected = *(((u32 *)io_bio->csum) + icsum); 3214 3215 kaddr = kmap_atomic(page); 3216 csum = btrfs_csum_data(kaddr + pgoff, csum, len); 3217 btrfs_csum_final(csum, (u8 *)&csum); 3218 if (csum != csum_expected) 3219 goto zeroit; 3220 3221 kunmap_atomic(kaddr); 3222 return 0; 3223 zeroit: 3224 btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected, 3225 io_bio->mirror_num); 3226 memset(kaddr + pgoff, 1, len); 3227 flush_dcache_page(page); 3228 kunmap_atomic(kaddr); 3229 return -EIO; 3230 } 3231 3232 /* 3233 * when reads are done, we need to check csums to verify the data is correct 3234 * if there's a match, we allow the bio to finish. If not, the code in 3235 * extent_io.c will try to find good copies for us. 3236 */ 3237 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio, 3238 u64 phy_offset, struct page *page, 3239 u64 start, u64 end, int mirror) 3240 { 3241 size_t offset = start - page_offset(page); 3242 struct inode *inode = page->mapping->host; 3243 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 3244 struct btrfs_root *root = BTRFS_I(inode)->root; 3245 3246 if (PageChecked(page)) { 3247 ClearPageChecked(page); 3248 return 0; 3249 } 3250 3251 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) 3252 return 0; 3253 3254 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && 3255 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { 3256 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM); 3257 return 0; 3258 } 3259 3260 phy_offset >>= inode->i_sb->s_blocksize_bits; 3261 return __readpage_endio_check(inode, io_bio, phy_offset, page, offset, 3262 start, (size_t)(end - start + 1)); 3263 } 3264 3265 /* 3266 * btrfs_add_delayed_iput - perform a delayed iput on @inode 3267 * 3268 * @inode: The inode we want to perform iput on 3269 * 3270 * This function uses the generic vfs_inode::i_count to track whether we should 3271 * just decrement it (in case it's > 1) or if this is the last iput then link 3272 * the inode to the delayed iput machinery. Delayed iputs are processed at 3273 * transaction commit time/superblock commit/cleaner kthread. 3274 */ 3275 void btrfs_add_delayed_iput(struct inode *inode) 3276 { 3277 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3278 struct btrfs_inode *binode = BTRFS_I(inode); 3279 3280 if (atomic_add_unless(&inode->i_count, -1, 1)) 3281 return; 3282 3283 spin_lock(&fs_info->delayed_iput_lock); 3284 ASSERT(list_empty(&binode->delayed_iput)); 3285 list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs); 3286 spin_unlock(&fs_info->delayed_iput_lock); 3287 } 3288 3289 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info) 3290 { 3291 3292 spin_lock(&fs_info->delayed_iput_lock); 3293 while (!list_empty(&fs_info->delayed_iputs)) { 3294 struct btrfs_inode *inode; 3295 3296 inode = list_first_entry(&fs_info->delayed_iputs, 3297 struct btrfs_inode, delayed_iput); 3298 list_del_init(&inode->delayed_iput); 3299 spin_unlock(&fs_info->delayed_iput_lock); 3300 iput(&inode->vfs_inode); 3301 spin_lock(&fs_info->delayed_iput_lock); 3302 } 3303 spin_unlock(&fs_info->delayed_iput_lock); 3304 } 3305 3306 /* 3307 * This creates an orphan entry for the given inode in case something goes wrong 3308 * in the middle of an unlink. 3309 */ 3310 int btrfs_orphan_add(struct btrfs_trans_handle *trans, 3311 struct btrfs_inode *inode) 3312 { 3313 int ret; 3314 3315 ret = btrfs_insert_orphan_item(trans, inode->root, btrfs_ino(inode)); 3316 if (ret && ret != -EEXIST) { 3317 btrfs_abort_transaction(trans, ret); 3318 return ret; 3319 } 3320 3321 return 0; 3322 } 3323 3324 /* 3325 * We have done the delete so we can go ahead and remove the orphan item for 3326 * this particular inode. 3327 */ 3328 static int btrfs_orphan_del(struct btrfs_trans_handle *trans, 3329 struct btrfs_inode *inode) 3330 { 3331 return btrfs_del_orphan_item(trans, inode->root, btrfs_ino(inode)); 3332 } 3333 3334 /* 3335 * this cleans up any orphans that may be left on the list from the last use 3336 * of this root. 3337 */ 3338 int btrfs_orphan_cleanup(struct btrfs_root *root) 3339 { 3340 struct btrfs_fs_info *fs_info = root->fs_info; 3341 struct btrfs_path *path; 3342 struct extent_buffer *leaf; 3343 struct btrfs_key key, found_key; 3344 struct btrfs_trans_handle *trans; 3345 struct inode *inode; 3346 u64 last_objectid = 0; 3347 int ret = 0, nr_unlink = 0; 3348 3349 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED)) 3350 return 0; 3351 3352 path = btrfs_alloc_path(); 3353 if (!path) { 3354 ret = -ENOMEM; 3355 goto out; 3356 } 3357 path->reada = READA_BACK; 3358 3359 key.objectid = BTRFS_ORPHAN_OBJECTID; 3360 key.type = BTRFS_ORPHAN_ITEM_KEY; 3361 key.offset = (u64)-1; 3362 3363 while (1) { 3364 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3365 if (ret < 0) 3366 goto out; 3367 3368 /* 3369 * if ret == 0 means we found what we were searching for, which 3370 * is weird, but possible, so only screw with path if we didn't 3371 * find the key and see if we have stuff that matches 3372 */ 3373 if (ret > 0) { 3374 ret = 0; 3375 if (path->slots[0] == 0) 3376 break; 3377 path->slots[0]--; 3378 } 3379 3380 /* pull out the item */ 3381 leaf = path->nodes[0]; 3382 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 3383 3384 /* make sure the item matches what we want */ 3385 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) 3386 break; 3387 if (found_key.type != BTRFS_ORPHAN_ITEM_KEY) 3388 break; 3389 3390 /* release the path since we're done with it */ 3391 btrfs_release_path(path); 3392 3393 /* 3394 * this is where we are basically btrfs_lookup, without the 3395 * crossing root thing. we store the inode number in the 3396 * offset of the orphan item. 3397 */ 3398 3399 if (found_key.offset == last_objectid) { 3400 btrfs_err(fs_info, 3401 "Error removing orphan entry, stopping orphan cleanup"); 3402 ret = -EINVAL; 3403 goto out; 3404 } 3405 3406 last_objectid = found_key.offset; 3407 3408 found_key.objectid = found_key.offset; 3409 found_key.type = BTRFS_INODE_ITEM_KEY; 3410 found_key.offset = 0; 3411 inode = btrfs_iget(fs_info->sb, &found_key, root, NULL); 3412 ret = PTR_ERR_OR_ZERO(inode); 3413 if (ret && ret != -ENOENT) 3414 goto out; 3415 3416 if (ret == -ENOENT && root == fs_info->tree_root) { 3417 struct btrfs_root *dead_root; 3418 struct btrfs_fs_info *fs_info = root->fs_info; 3419 int is_dead_root = 0; 3420 3421 /* 3422 * this is an orphan in the tree root. Currently these 3423 * could come from 2 sources: 3424 * a) a snapshot deletion in progress 3425 * b) a free space cache inode 3426 * We need to distinguish those two, as the snapshot 3427 * orphan must not get deleted. 3428 * find_dead_roots already ran before us, so if this 3429 * is a snapshot deletion, we should find the root 3430 * in the dead_roots list 3431 */ 3432 spin_lock(&fs_info->trans_lock); 3433 list_for_each_entry(dead_root, &fs_info->dead_roots, 3434 root_list) { 3435 if (dead_root->root_key.objectid == 3436 found_key.objectid) { 3437 is_dead_root = 1; 3438 break; 3439 } 3440 } 3441 spin_unlock(&fs_info->trans_lock); 3442 if (is_dead_root) { 3443 /* prevent this orphan from being found again */ 3444 key.offset = found_key.objectid - 1; 3445 continue; 3446 } 3447 3448 } 3449 3450 /* 3451 * If we have an inode with links, there are a couple of 3452 * possibilities. Old kernels (before v3.12) used to create an 3453 * orphan item for truncate indicating that there were possibly 3454 * extent items past i_size that needed to be deleted. In v3.12, 3455 * truncate was changed to update i_size in sync with the extent 3456 * items, but the (useless) orphan item was still created. Since 3457 * v4.18, we don't create the orphan item for truncate at all. 3458 * 3459 * So, this item could mean that we need to do a truncate, but 3460 * only if this filesystem was last used on a pre-v3.12 kernel 3461 * and was not cleanly unmounted. The odds of that are quite 3462 * slim, and it's a pain to do the truncate now, so just delete 3463 * the orphan item. 3464 * 3465 * It's also possible that this orphan item was supposed to be 3466 * deleted but wasn't. The inode number may have been reused, 3467 * but either way, we can delete the orphan item. 3468 */ 3469 if (ret == -ENOENT || inode->i_nlink) { 3470 if (!ret) 3471 iput(inode); 3472 trans = btrfs_start_transaction(root, 1); 3473 if (IS_ERR(trans)) { 3474 ret = PTR_ERR(trans); 3475 goto out; 3476 } 3477 btrfs_debug(fs_info, "auto deleting %Lu", 3478 found_key.objectid); 3479 ret = btrfs_del_orphan_item(trans, root, 3480 found_key.objectid); 3481 btrfs_end_transaction(trans); 3482 if (ret) 3483 goto out; 3484 continue; 3485 } 3486 3487 nr_unlink++; 3488 3489 /* this will do delete_inode and everything for us */ 3490 iput(inode); 3491 if (ret) 3492 goto out; 3493 } 3494 /* release the path since we're done with it */ 3495 btrfs_release_path(path); 3496 3497 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE; 3498 3499 if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) { 3500 trans = btrfs_join_transaction(root); 3501 if (!IS_ERR(trans)) 3502 btrfs_end_transaction(trans); 3503 } 3504 3505 if (nr_unlink) 3506 btrfs_debug(fs_info, "unlinked %d orphans", nr_unlink); 3507 3508 out: 3509 if (ret) 3510 btrfs_err(fs_info, "could not do orphan cleanup %d", ret); 3511 btrfs_free_path(path); 3512 return ret; 3513 } 3514 3515 /* 3516 * very simple check to peek ahead in the leaf looking for xattrs. If we 3517 * don't find any xattrs, we know there can't be any acls. 3518 * 3519 * slot is the slot the inode is in, objectid is the objectid of the inode 3520 */ 3521 static noinline int acls_after_inode_item(struct extent_buffer *leaf, 3522 int slot, u64 objectid, 3523 int *first_xattr_slot) 3524 { 3525 u32 nritems = btrfs_header_nritems(leaf); 3526 struct btrfs_key found_key; 3527 static u64 xattr_access = 0; 3528 static u64 xattr_default = 0; 3529 int scanned = 0; 3530 3531 if (!xattr_access) { 3532 xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS, 3533 strlen(XATTR_NAME_POSIX_ACL_ACCESS)); 3534 xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT, 3535 strlen(XATTR_NAME_POSIX_ACL_DEFAULT)); 3536 } 3537 3538 slot++; 3539 *first_xattr_slot = -1; 3540 while (slot < nritems) { 3541 btrfs_item_key_to_cpu(leaf, &found_key, slot); 3542 3543 /* we found a different objectid, there must not be acls */ 3544 if (found_key.objectid != objectid) 3545 return 0; 3546 3547 /* we found an xattr, assume we've got an acl */ 3548 if (found_key.type == BTRFS_XATTR_ITEM_KEY) { 3549 if (*first_xattr_slot == -1) 3550 *first_xattr_slot = slot; 3551 if (found_key.offset == xattr_access || 3552 found_key.offset == xattr_default) 3553 return 1; 3554 } 3555 3556 /* 3557 * we found a key greater than an xattr key, there can't 3558 * be any acls later on 3559 */ 3560 if (found_key.type > BTRFS_XATTR_ITEM_KEY) 3561 return 0; 3562 3563 slot++; 3564 scanned++; 3565 3566 /* 3567 * it goes inode, inode backrefs, xattrs, extents, 3568 * so if there are a ton of hard links to an inode there can 3569 * be a lot of backrefs. Don't waste time searching too hard, 3570 * this is just an optimization 3571 */ 3572 if (scanned >= 8) 3573 break; 3574 } 3575 /* we hit the end of the leaf before we found an xattr or 3576 * something larger than an xattr. We have to assume the inode 3577 * has acls 3578 */ 3579 if (*first_xattr_slot == -1) 3580 *first_xattr_slot = slot; 3581 return 1; 3582 } 3583 3584 /* 3585 * read an inode from the btree into the in-memory inode 3586 */ 3587 static int btrfs_read_locked_inode(struct inode *inode) 3588 { 3589 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 3590 struct btrfs_path *path; 3591 struct extent_buffer *leaf; 3592 struct btrfs_inode_item *inode_item; 3593 struct btrfs_root *root = BTRFS_I(inode)->root; 3594 struct btrfs_key location; 3595 unsigned long ptr; 3596 int maybe_acls; 3597 u32 rdev; 3598 int ret; 3599 bool filled = false; 3600 int first_xattr_slot; 3601 3602 ret = btrfs_fill_inode(inode, &rdev); 3603 if (!ret) 3604 filled = true; 3605 3606 path = btrfs_alloc_path(); 3607 if (!path) 3608 return -ENOMEM; 3609 3610 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location)); 3611 3612 ret = btrfs_lookup_inode(NULL, root, path, &location, 0); 3613 if (ret) { 3614 btrfs_free_path(path); 3615 return ret; 3616 } 3617 3618 leaf = path->nodes[0]; 3619 3620 if (filled) 3621 goto cache_index; 3622 3623 inode_item = btrfs_item_ptr(leaf, path->slots[0], 3624 struct btrfs_inode_item); 3625 inode->i_mode = btrfs_inode_mode(leaf, inode_item); 3626 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item)); 3627 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item)); 3628 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item)); 3629 btrfs_i_size_write(BTRFS_I(inode), btrfs_inode_size(leaf, inode_item)); 3630 3631 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->atime); 3632 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->atime); 3633 3634 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->mtime); 3635 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->mtime); 3636 3637 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime); 3638 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime); 3639 3640 BTRFS_I(inode)->i_otime.tv_sec = 3641 btrfs_timespec_sec(leaf, &inode_item->otime); 3642 BTRFS_I(inode)->i_otime.tv_nsec = 3643 btrfs_timespec_nsec(leaf, &inode_item->otime); 3644 3645 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item)); 3646 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item); 3647 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item); 3648 3649 inode_set_iversion_queried(inode, 3650 btrfs_inode_sequence(leaf, inode_item)); 3651 inode->i_generation = BTRFS_I(inode)->generation; 3652 inode->i_rdev = 0; 3653 rdev = btrfs_inode_rdev(leaf, inode_item); 3654 3655 BTRFS_I(inode)->index_cnt = (u64)-1; 3656 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item); 3657 3658 cache_index: 3659 /* 3660 * If we were modified in the current generation and evicted from memory 3661 * and then re-read we need to do a full sync since we don't have any 3662 * idea about which extents were modified before we were evicted from 3663 * cache. 3664 * 3665 * This is required for both inode re-read from disk and delayed inode 3666 * in delayed_nodes_tree. 3667 */ 3668 if (BTRFS_I(inode)->last_trans == fs_info->generation) 3669 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 3670 &BTRFS_I(inode)->runtime_flags); 3671 3672 /* 3673 * We don't persist the id of the transaction where an unlink operation 3674 * against the inode was last made. So here we assume the inode might 3675 * have been evicted, and therefore the exact value of last_unlink_trans 3676 * lost, and set it to last_trans to avoid metadata inconsistencies 3677 * between the inode and its parent if the inode is fsync'ed and the log 3678 * replayed. For example, in the scenario: 3679 * 3680 * touch mydir/foo 3681 * ln mydir/foo mydir/bar 3682 * sync 3683 * unlink mydir/bar 3684 * echo 2 > /proc/sys/vm/drop_caches # evicts inode 3685 * xfs_io -c fsync mydir/foo 3686 * <power failure> 3687 * mount fs, triggers fsync log replay 3688 * 3689 * We must make sure that when we fsync our inode foo we also log its 3690 * parent inode, otherwise after log replay the parent still has the 3691 * dentry with the "bar" name but our inode foo has a link count of 1 3692 * and doesn't have an inode ref with the name "bar" anymore. 3693 * 3694 * Setting last_unlink_trans to last_trans is a pessimistic approach, 3695 * but it guarantees correctness at the expense of occasional full 3696 * transaction commits on fsync if our inode is a directory, or if our 3697 * inode is not a directory, logging its parent unnecessarily. 3698 */ 3699 BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans; 3700 3701 path->slots[0]++; 3702 if (inode->i_nlink != 1 || 3703 path->slots[0] >= btrfs_header_nritems(leaf)) 3704 goto cache_acl; 3705 3706 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]); 3707 if (location.objectid != btrfs_ino(BTRFS_I(inode))) 3708 goto cache_acl; 3709 3710 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); 3711 if (location.type == BTRFS_INODE_REF_KEY) { 3712 struct btrfs_inode_ref *ref; 3713 3714 ref = (struct btrfs_inode_ref *)ptr; 3715 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref); 3716 } else if (location.type == BTRFS_INODE_EXTREF_KEY) { 3717 struct btrfs_inode_extref *extref; 3718 3719 extref = (struct btrfs_inode_extref *)ptr; 3720 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf, 3721 extref); 3722 } 3723 cache_acl: 3724 /* 3725 * try to precache a NULL acl entry for files that don't have 3726 * any xattrs or acls 3727 */ 3728 maybe_acls = acls_after_inode_item(leaf, path->slots[0], 3729 btrfs_ino(BTRFS_I(inode)), &first_xattr_slot); 3730 if (first_xattr_slot != -1) { 3731 path->slots[0] = first_xattr_slot; 3732 ret = btrfs_load_inode_props(inode, path); 3733 if (ret) 3734 btrfs_err(fs_info, 3735 "error loading props for ino %llu (root %llu): %d", 3736 btrfs_ino(BTRFS_I(inode)), 3737 root->root_key.objectid, ret); 3738 } 3739 btrfs_free_path(path); 3740 3741 if (!maybe_acls) 3742 cache_no_acl(inode); 3743 3744 switch (inode->i_mode & S_IFMT) { 3745 case S_IFREG: 3746 inode->i_mapping->a_ops = &btrfs_aops; 3747 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 3748 inode->i_fop = &btrfs_file_operations; 3749 inode->i_op = &btrfs_file_inode_operations; 3750 break; 3751 case S_IFDIR: 3752 inode->i_fop = &btrfs_dir_file_operations; 3753 inode->i_op = &btrfs_dir_inode_operations; 3754 break; 3755 case S_IFLNK: 3756 inode->i_op = &btrfs_symlink_inode_operations; 3757 inode_nohighmem(inode); 3758 inode->i_mapping->a_ops = &btrfs_symlink_aops; 3759 break; 3760 default: 3761 inode->i_op = &btrfs_special_inode_operations; 3762 init_special_inode(inode, inode->i_mode, rdev); 3763 break; 3764 } 3765 3766 btrfs_sync_inode_flags_to_i_flags(inode); 3767 return 0; 3768 } 3769 3770 /* 3771 * given a leaf and an inode, copy the inode fields into the leaf 3772 */ 3773 static void fill_inode_item(struct btrfs_trans_handle *trans, 3774 struct extent_buffer *leaf, 3775 struct btrfs_inode_item *item, 3776 struct inode *inode) 3777 { 3778 struct btrfs_map_token token; 3779 3780 btrfs_init_map_token(&token); 3781 3782 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token); 3783 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token); 3784 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size, 3785 &token); 3786 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token); 3787 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token); 3788 3789 btrfs_set_token_timespec_sec(leaf, &item->atime, 3790 inode->i_atime.tv_sec, &token); 3791 btrfs_set_token_timespec_nsec(leaf, &item->atime, 3792 inode->i_atime.tv_nsec, &token); 3793 3794 btrfs_set_token_timespec_sec(leaf, &item->mtime, 3795 inode->i_mtime.tv_sec, &token); 3796 btrfs_set_token_timespec_nsec(leaf, &item->mtime, 3797 inode->i_mtime.tv_nsec, &token); 3798 3799 btrfs_set_token_timespec_sec(leaf, &item->ctime, 3800 inode->i_ctime.tv_sec, &token); 3801 btrfs_set_token_timespec_nsec(leaf, &item->ctime, 3802 inode->i_ctime.tv_nsec, &token); 3803 3804 btrfs_set_token_timespec_sec(leaf, &item->otime, 3805 BTRFS_I(inode)->i_otime.tv_sec, &token); 3806 btrfs_set_token_timespec_nsec(leaf, &item->otime, 3807 BTRFS_I(inode)->i_otime.tv_nsec, &token); 3808 3809 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode), 3810 &token); 3811 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation, 3812 &token); 3813 btrfs_set_token_inode_sequence(leaf, item, inode_peek_iversion(inode), 3814 &token); 3815 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token); 3816 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token); 3817 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token); 3818 btrfs_set_token_inode_block_group(leaf, item, 0, &token); 3819 } 3820 3821 /* 3822 * copy everything in the in-memory inode into the btree. 3823 */ 3824 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans, 3825 struct btrfs_root *root, struct inode *inode) 3826 { 3827 struct btrfs_inode_item *inode_item; 3828 struct btrfs_path *path; 3829 struct extent_buffer *leaf; 3830 int ret; 3831 3832 path = btrfs_alloc_path(); 3833 if (!path) 3834 return -ENOMEM; 3835 3836 path->leave_spinning = 1; 3837 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location, 3838 1); 3839 if (ret) { 3840 if (ret > 0) 3841 ret = -ENOENT; 3842 goto failed; 3843 } 3844 3845 leaf = path->nodes[0]; 3846 inode_item = btrfs_item_ptr(leaf, path->slots[0], 3847 struct btrfs_inode_item); 3848 3849 fill_inode_item(trans, leaf, inode_item, inode); 3850 btrfs_mark_buffer_dirty(leaf); 3851 btrfs_set_inode_last_trans(trans, inode); 3852 ret = 0; 3853 failed: 3854 btrfs_free_path(path); 3855 return ret; 3856 } 3857 3858 /* 3859 * copy everything in the in-memory inode into the btree. 3860 */ 3861 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans, 3862 struct btrfs_root *root, struct inode *inode) 3863 { 3864 struct btrfs_fs_info *fs_info = root->fs_info; 3865 int ret; 3866 3867 /* 3868 * If the inode is a free space inode, we can deadlock during commit 3869 * if we put it into the delayed code. 3870 * 3871 * The data relocation inode should also be directly updated 3872 * without delay 3873 */ 3874 if (!btrfs_is_free_space_inode(BTRFS_I(inode)) 3875 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID 3876 && !test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) { 3877 btrfs_update_root_times(trans, root); 3878 3879 ret = btrfs_delayed_update_inode(trans, root, inode); 3880 if (!ret) 3881 btrfs_set_inode_last_trans(trans, inode); 3882 return ret; 3883 } 3884 3885 return btrfs_update_inode_item(trans, root, inode); 3886 } 3887 3888 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, 3889 struct btrfs_root *root, 3890 struct inode *inode) 3891 { 3892 int ret; 3893 3894 ret = btrfs_update_inode(trans, root, inode); 3895 if (ret == -ENOSPC) 3896 return btrfs_update_inode_item(trans, root, inode); 3897 return ret; 3898 } 3899 3900 /* 3901 * unlink helper that gets used here in inode.c and in the tree logging 3902 * recovery code. It remove a link in a directory with a given name, and 3903 * also drops the back refs in the inode to the directory 3904 */ 3905 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans, 3906 struct btrfs_root *root, 3907 struct btrfs_inode *dir, 3908 struct btrfs_inode *inode, 3909 const char *name, int name_len) 3910 { 3911 struct btrfs_fs_info *fs_info = root->fs_info; 3912 struct btrfs_path *path; 3913 int ret = 0; 3914 struct extent_buffer *leaf; 3915 struct btrfs_dir_item *di; 3916 struct btrfs_key key; 3917 u64 index; 3918 u64 ino = btrfs_ino(inode); 3919 u64 dir_ino = btrfs_ino(dir); 3920 3921 path = btrfs_alloc_path(); 3922 if (!path) { 3923 ret = -ENOMEM; 3924 goto out; 3925 } 3926 3927 path->leave_spinning = 1; 3928 di = btrfs_lookup_dir_item(trans, root, path, dir_ino, 3929 name, name_len, -1); 3930 if (IS_ERR(di)) { 3931 ret = PTR_ERR(di); 3932 goto err; 3933 } 3934 if (!di) { 3935 ret = -ENOENT; 3936 goto err; 3937 } 3938 leaf = path->nodes[0]; 3939 btrfs_dir_item_key_to_cpu(leaf, di, &key); 3940 ret = btrfs_delete_one_dir_name(trans, root, path, di); 3941 if (ret) 3942 goto err; 3943 btrfs_release_path(path); 3944 3945 /* 3946 * If we don't have dir index, we have to get it by looking up 3947 * the inode ref, since we get the inode ref, remove it directly, 3948 * it is unnecessary to do delayed deletion. 3949 * 3950 * But if we have dir index, needn't search inode ref to get it. 3951 * Since the inode ref is close to the inode item, it is better 3952 * that we delay to delete it, and just do this deletion when 3953 * we update the inode item. 3954 */ 3955 if (inode->dir_index) { 3956 ret = btrfs_delayed_delete_inode_ref(inode); 3957 if (!ret) { 3958 index = inode->dir_index; 3959 goto skip_backref; 3960 } 3961 } 3962 3963 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino, 3964 dir_ino, &index); 3965 if (ret) { 3966 btrfs_info(fs_info, 3967 "failed to delete reference to %.*s, inode %llu parent %llu", 3968 name_len, name, ino, dir_ino); 3969 btrfs_abort_transaction(trans, ret); 3970 goto err; 3971 } 3972 skip_backref: 3973 ret = btrfs_delete_delayed_dir_index(trans, dir, index); 3974 if (ret) { 3975 btrfs_abort_transaction(trans, ret); 3976 goto err; 3977 } 3978 3979 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, inode, 3980 dir_ino); 3981 if (ret != 0 && ret != -ENOENT) { 3982 btrfs_abort_transaction(trans, ret); 3983 goto err; 3984 } 3985 3986 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, dir, 3987 index); 3988 if (ret == -ENOENT) 3989 ret = 0; 3990 else if (ret) 3991 btrfs_abort_transaction(trans, ret); 3992 err: 3993 btrfs_free_path(path); 3994 if (ret) 3995 goto out; 3996 3997 btrfs_i_size_write(dir, dir->vfs_inode.i_size - name_len * 2); 3998 inode_inc_iversion(&inode->vfs_inode); 3999 inode_inc_iversion(&dir->vfs_inode); 4000 inode->vfs_inode.i_ctime = dir->vfs_inode.i_mtime = 4001 dir->vfs_inode.i_ctime = current_time(&inode->vfs_inode); 4002 ret = btrfs_update_inode(trans, root, &dir->vfs_inode); 4003 out: 4004 return ret; 4005 } 4006 4007 int btrfs_unlink_inode(struct btrfs_trans_handle *trans, 4008 struct btrfs_root *root, 4009 struct btrfs_inode *dir, struct btrfs_inode *inode, 4010 const char *name, int name_len) 4011 { 4012 int ret; 4013 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len); 4014 if (!ret) { 4015 drop_nlink(&inode->vfs_inode); 4016 ret = btrfs_update_inode(trans, root, &inode->vfs_inode); 4017 } 4018 return ret; 4019 } 4020 4021 /* 4022 * helper to start transaction for unlink and rmdir. 4023 * 4024 * unlink and rmdir are special in btrfs, they do not always free space, so 4025 * if we cannot make our reservations the normal way try and see if there is 4026 * plenty of slack room in the global reserve to migrate, otherwise we cannot 4027 * allow the unlink to occur. 4028 */ 4029 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir) 4030 { 4031 struct btrfs_root *root = BTRFS_I(dir)->root; 4032 4033 /* 4034 * 1 for the possible orphan item 4035 * 1 for the dir item 4036 * 1 for the dir index 4037 * 1 for the inode ref 4038 * 1 for the inode 4039 */ 4040 return btrfs_start_transaction_fallback_global_rsv(root, 5, 5); 4041 } 4042 4043 static int btrfs_unlink(struct inode *dir, struct dentry *dentry) 4044 { 4045 struct btrfs_root *root = BTRFS_I(dir)->root; 4046 struct btrfs_trans_handle *trans; 4047 struct inode *inode = d_inode(dentry); 4048 int ret; 4049 4050 trans = __unlink_start_trans(dir); 4051 if (IS_ERR(trans)) 4052 return PTR_ERR(trans); 4053 4054 btrfs_record_unlink_dir(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), 4055 0); 4056 4057 ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir), 4058 BTRFS_I(d_inode(dentry)), dentry->d_name.name, 4059 dentry->d_name.len); 4060 if (ret) 4061 goto out; 4062 4063 if (inode->i_nlink == 0) { 4064 ret = btrfs_orphan_add(trans, BTRFS_I(inode)); 4065 if (ret) 4066 goto out; 4067 } 4068 4069 out: 4070 btrfs_end_transaction(trans); 4071 btrfs_btree_balance_dirty(root->fs_info); 4072 return ret; 4073 } 4074 4075 static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, 4076 struct inode *dir, u64 objectid, 4077 const char *name, int name_len) 4078 { 4079 struct btrfs_root *root = BTRFS_I(dir)->root; 4080 struct btrfs_path *path; 4081 struct extent_buffer *leaf; 4082 struct btrfs_dir_item *di; 4083 struct btrfs_key key; 4084 u64 index; 4085 int ret; 4086 u64 dir_ino = btrfs_ino(BTRFS_I(dir)); 4087 4088 path = btrfs_alloc_path(); 4089 if (!path) 4090 return -ENOMEM; 4091 4092 di = btrfs_lookup_dir_item(trans, root, path, dir_ino, 4093 name, name_len, -1); 4094 if (IS_ERR_OR_NULL(di)) { 4095 if (!di) 4096 ret = -ENOENT; 4097 else 4098 ret = PTR_ERR(di); 4099 goto out; 4100 } 4101 4102 leaf = path->nodes[0]; 4103 btrfs_dir_item_key_to_cpu(leaf, di, &key); 4104 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); 4105 ret = btrfs_delete_one_dir_name(trans, root, path, di); 4106 if (ret) { 4107 btrfs_abort_transaction(trans, ret); 4108 goto out; 4109 } 4110 btrfs_release_path(path); 4111 4112 ret = btrfs_del_root_ref(trans, objectid, root->root_key.objectid, 4113 dir_ino, &index, name, name_len); 4114 if (ret < 0) { 4115 if (ret != -ENOENT) { 4116 btrfs_abort_transaction(trans, ret); 4117 goto out; 4118 } 4119 di = btrfs_search_dir_index_item(root, path, dir_ino, 4120 name, name_len); 4121 if (IS_ERR_OR_NULL(di)) { 4122 if (!di) 4123 ret = -ENOENT; 4124 else 4125 ret = PTR_ERR(di); 4126 btrfs_abort_transaction(trans, ret); 4127 goto out; 4128 } 4129 4130 leaf = path->nodes[0]; 4131 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 4132 index = key.offset; 4133 } 4134 btrfs_release_path(path); 4135 4136 ret = btrfs_delete_delayed_dir_index(trans, BTRFS_I(dir), index); 4137 if (ret) { 4138 btrfs_abort_transaction(trans, ret); 4139 goto out; 4140 } 4141 4142 btrfs_i_size_write(BTRFS_I(dir), dir->i_size - name_len * 2); 4143 inode_inc_iversion(dir); 4144 dir->i_mtime = dir->i_ctime = current_time(dir); 4145 ret = btrfs_update_inode_fallback(trans, root, dir); 4146 if (ret) 4147 btrfs_abort_transaction(trans, ret); 4148 out: 4149 btrfs_free_path(path); 4150 return ret; 4151 } 4152 4153 /* 4154 * Helper to check if the subvolume references other subvolumes or if it's 4155 * default. 4156 */ 4157 static noinline int may_destroy_subvol(struct btrfs_root *root) 4158 { 4159 struct btrfs_fs_info *fs_info = root->fs_info; 4160 struct btrfs_path *path; 4161 struct btrfs_dir_item *di; 4162 struct btrfs_key key; 4163 u64 dir_id; 4164 int ret; 4165 4166 path = btrfs_alloc_path(); 4167 if (!path) 4168 return -ENOMEM; 4169 4170 /* Make sure this root isn't set as the default subvol */ 4171 dir_id = btrfs_super_root_dir(fs_info->super_copy); 4172 di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path, 4173 dir_id, "default", 7, 0); 4174 if (di && !IS_ERR(di)) { 4175 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key); 4176 if (key.objectid == root->root_key.objectid) { 4177 ret = -EPERM; 4178 btrfs_err(fs_info, 4179 "deleting default subvolume %llu is not allowed", 4180 key.objectid); 4181 goto out; 4182 } 4183 btrfs_release_path(path); 4184 } 4185 4186 key.objectid = root->root_key.objectid; 4187 key.type = BTRFS_ROOT_REF_KEY; 4188 key.offset = (u64)-1; 4189 4190 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 4191 if (ret < 0) 4192 goto out; 4193 BUG_ON(ret == 0); 4194 4195 ret = 0; 4196 if (path->slots[0] > 0) { 4197 path->slots[0]--; 4198 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 4199 if (key.objectid == root->root_key.objectid && 4200 key.type == BTRFS_ROOT_REF_KEY) 4201 ret = -ENOTEMPTY; 4202 } 4203 out: 4204 btrfs_free_path(path); 4205 return ret; 4206 } 4207 4208 /* Delete all dentries for inodes belonging to the root */ 4209 static void btrfs_prune_dentries(struct btrfs_root *root) 4210 { 4211 struct btrfs_fs_info *fs_info = root->fs_info; 4212 struct rb_node *node; 4213 struct rb_node *prev; 4214 struct btrfs_inode *entry; 4215 struct inode *inode; 4216 u64 objectid = 0; 4217 4218 if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 4219 WARN_ON(btrfs_root_refs(&root->root_item) != 0); 4220 4221 spin_lock(&root->inode_lock); 4222 again: 4223 node = root->inode_tree.rb_node; 4224 prev = NULL; 4225 while (node) { 4226 prev = node; 4227 entry = rb_entry(node, struct btrfs_inode, rb_node); 4228 4229 if (objectid < btrfs_ino(entry)) 4230 node = node->rb_left; 4231 else if (objectid > btrfs_ino(entry)) 4232 node = node->rb_right; 4233 else 4234 break; 4235 } 4236 if (!node) { 4237 while (prev) { 4238 entry = rb_entry(prev, struct btrfs_inode, rb_node); 4239 if (objectid <= btrfs_ino(entry)) { 4240 node = prev; 4241 break; 4242 } 4243 prev = rb_next(prev); 4244 } 4245 } 4246 while (node) { 4247 entry = rb_entry(node, struct btrfs_inode, rb_node); 4248 objectid = btrfs_ino(entry) + 1; 4249 inode = igrab(&entry->vfs_inode); 4250 if (inode) { 4251 spin_unlock(&root->inode_lock); 4252 if (atomic_read(&inode->i_count) > 1) 4253 d_prune_aliases(inode); 4254 /* 4255 * btrfs_drop_inode will have it removed from the inode 4256 * cache when its usage count hits zero. 4257 */ 4258 iput(inode); 4259 cond_resched(); 4260 spin_lock(&root->inode_lock); 4261 goto again; 4262 } 4263 4264 if (cond_resched_lock(&root->inode_lock)) 4265 goto again; 4266 4267 node = rb_next(node); 4268 } 4269 spin_unlock(&root->inode_lock); 4270 } 4271 4272 int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry) 4273 { 4274 struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb); 4275 struct btrfs_root *root = BTRFS_I(dir)->root; 4276 struct inode *inode = d_inode(dentry); 4277 struct btrfs_root *dest = BTRFS_I(inode)->root; 4278 struct btrfs_trans_handle *trans; 4279 struct btrfs_block_rsv block_rsv; 4280 u64 root_flags; 4281 int ret; 4282 int err; 4283 4284 /* 4285 * Don't allow to delete a subvolume with send in progress. This is 4286 * inside the inode lock so the error handling that has to drop the bit 4287 * again is not run concurrently. 4288 */ 4289 spin_lock(&dest->root_item_lock); 4290 root_flags = btrfs_root_flags(&dest->root_item); 4291 if (dest->send_in_progress == 0) { 4292 btrfs_set_root_flags(&dest->root_item, 4293 root_flags | BTRFS_ROOT_SUBVOL_DEAD); 4294 spin_unlock(&dest->root_item_lock); 4295 } else { 4296 spin_unlock(&dest->root_item_lock); 4297 btrfs_warn(fs_info, 4298 "attempt to delete subvolume %llu during send", 4299 dest->root_key.objectid); 4300 return -EPERM; 4301 } 4302 4303 down_write(&fs_info->subvol_sem); 4304 4305 err = may_destroy_subvol(dest); 4306 if (err) 4307 goto out_up_write; 4308 4309 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); 4310 /* 4311 * One for dir inode, 4312 * two for dir entries, 4313 * two for root ref/backref. 4314 */ 4315 err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, true); 4316 if (err) 4317 goto out_up_write; 4318 4319 trans = btrfs_start_transaction(root, 0); 4320 if (IS_ERR(trans)) { 4321 err = PTR_ERR(trans); 4322 goto out_release; 4323 } 4324 trans->block_rsv = &block_rsv; 4325 trans->bytes_reserved = block_rsv.size; 4326 4327 btrfs_record_snapshot_destroy(trans, BTRFS_I(dir)); 4328 4329 ret = btrfs_unlink_subvol(trans, dir, dest->root_key.objectid, 4330 dentry->d_name.name, dentry->d_name.len); 4331 if (ret) { 4332 err = ret; 4333 btrfs_abort_transaction(trans, ret); 4334 goto out_end_trans; 4335 } 4336 4337 btrfs_record_root_in_trans(trans, dest); 4338 4339 memset(&dest->root_item.drop_progress, 0, 4340 sizeof(dest->root_item.drop_progress)); 4341 dest->root_item.drop_level = 0; 4342 btrfs_set_root_refs(&dest->root_item, 0); 4343 4344 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) { 4345 ret = btrfs_insert_orphan_item(trans, 4346 fs_info->tree_root, 4347 dest->root_key.objectid); 4348 if (ret) { 4349 btrfs_abort_transaction(trans, ret); 4350 err = ret; 4351 goto out_end_trans; 4352 } 4353 } 4354 4355 ret = btrfs_uuid_tree_remove(trans, dest->root_item.uuid, 4356 BTRFS_UUID_KEY_SUBVOL, 4357 dest->root_key.objectid); 4358 if (ret && ret != -ENOENT) { 4359 btrfs_abort_transaction(trans, ret); 4360 err = ret; 4361 goto out_end_trans; 4362 } 4363 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) { 4364 ret = btrfs_uuid_tree_remove(trans, 4365 dest->root_item.received_uuid, 4366 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 4367 dest->root_key.objectid); 4368 if (ret && ret != -ENOENT) { 4369 btrfs_abort_transaction(trans, ret); 4370 err = ret; 4371 goto out_end_trans; 4372 } 4373 } 4374 4375 out_end_trans: 4376 trans->block_rsv = NULL; 4377 trans->bytes_reserved = 0; 4378 ret = btrfs_end_transaction(trans); 4379 if (ret && !err) 4380 err = ret; 4381 inode->i_flags |= S_DEAD; 4382 out_release: 4383 btrfs_subvolume_release_metadata(fs_info, &block_rsv); 4384 out_up_write: 4385 up_write(&fs_info->subvol_sem); 4386 if (err) { 4387 spin_lock(&dest->root_item_lock); 4388 root_flags = btrfs_root_flags(&dest->root_item); 4389 btrfs_set_root_flags(&dest->root_item, 4390 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD); 4391 spin_unlock(&dest->root_item_lock); 4392 } else { 4393 d_invalidate(dentry); 4394 btrfs_prune_dentries(dest); 4395 ASSERT(dest->send_in_progress == 0); 4396 4397 /* the last ref */ 4398 if (dest->ino_cache_inode) { 4399 iput(dest->ino_cache_inode); 4400 dest->ino_cache_inode = NULL; 4401 } 4402 } 4403 4404 return err; 4405 } 4406 4407 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) 4408 { 4409 struct inode *inode = d_inode(dentry); 4410 int err = 0; 4411 struct btrfs_root *root = BTRFS_I(dir)->root; 4412 struct btrfs_trans_handle *trans; 4413 u64 last_unlink_trans; 4414 4415 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) 4416 return -ENOTEMPTY; 4417 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID) 4418 return btrfs_delete_subvolume(dir, dentry); 4419 4420 trans = __unlink_start_trans(dir); 4421 if (IS_ERR(trans)) 4422 return PTR_ERR(trans); 4423 4424 if (unlikely(btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { 4425 err = btrfs_unlink_subvol(trans, dir, 4426 BTRFS_I(inode)->location.objectid, 4427 dentry->d_name.name, 4428 dentry->d_name.len); 4429 goto out; 4430 } 4431 4432 err = btrfs_orphan_add(trans, BTRFS_I(inode)); 4433 if (err) 4434 goto out; 4435 4436 last_unlink_trans = BTRFS_I(inode)->last_unlink_trans; 4437 4438 /* now the directory is empty */ 4439 err = btrfs_unlink_inode(trans, root, BTRFS_I(dir), 4440 BTRFS_I(d_inode(dentry)), dentry->d_name.name, 4441 dentry->d_name.len); 4442 if (!err) { 4443 btrfs_i_size_write(BTRFS_I(inode), 0); 4444 /* 4445 * Propagate the last_unlink_trans value of the deleted dir to 4446 * its parent directory. This is to prevent an unrecoverable 4447 * log tree in the case we do something like this: 4448 * 1) create dir foo 4449 * 2) create snapshot under dir foo 4450 * 3) delete the snapshot 4451 * 4) rmdir foo 4452 * 5) mkdir foo 4453 * 6) fsync foo or some file inside foo 4454 */ 4455 if (last_unlink_trans >= trans->transid) 4456 BTRFS_I(dir)->last_unlink_trans = last_unlink_trans; 4457 } 4458 out: 4459 btrfs_end_transaction(trans); 4460 btrfs_btree_balance_dirty(root->fs_info); 4461 4462 return err; 4463 } 4464 4465 static int truncate_space_check(struct btrfs_trans_handle *trans, 4466 struct btrfs_root *root, 4467 u64 bytes_deleted) 4468 { 4469 struct btrfs_fs_info *fs_info = root->fs_info; 4470 int ret; 4471 4472 /* 4473 * This is only used to apply pressure to the enospc system, we don't 4474 * intend to use this reservation at all. 4475 */ 4476 bytes_deleted = btrfs_csum_bytes_to_leaves(fs_info, bytes_deleted); 4477 bytes_deleted *= fs_info->nodesize; 4478 ret = btrfs_block_rsv_add(root, &fs_info->trans_block_rsv, 4479 bytes_deleted, BTRFS_RESERVE_NO_FLUSH); 4480 if (!ret) { 4481 trace_btrfs_space_reservation(fs_info, "transaction", 4482 trans->transid, 4483 bytes_deleted, 1); 4484 trans->bytes_reserved += bytes_deleted; 4485 } 4486 return ret; 4487 4488 } 4489 4490 /* 4491 * Return this if we need to call truncate_block for the last bit of the 4492 * truncate. 4493 */ 4494 #define NEED_TRUNCATE_BLOCK 1 4495 4496 /* 4497 * this can truncate away extent items, csum items and directory items. 4498 * It starts at a high offset and removes keys until it can't find 4499 * any higher than new_size 4500 * 4501 * csum items that cross the new i_size are truncated to the new size 4502 * as well. 4503 * 4504 * min_type is the minimum key type to truncate down to. If set to 0, this 4505 * will kill all the items on this inode, including the INODE_ITEM_KEY. 4506 */ 4507 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, 4508 struct btrfs_root *root, 4509 struct inode *inode, 4510 u64 new_size, u32 min_type) 4511 { 4512 struct btrfs_fs_info *fs_info = root->fs_info; 4513 struct btrfs_path *path; 4514 struct extent_buffer *leaf; 4515 struct btrfs_file_extent_item *fi; 4516 struct btrfs_key key; 4517 struct btrfs_key found_key; 4518 u64 extent_start = 0; 4519 u64 extent_num_bytes = 0; 4520 u64 extent_offset = 0; 4521 u64 item_end = 0; 4522 u64 last_size = new_size; 4523 u32 found_type = (u8)-1; 4524 int found_extent; 4525 int del_item; 4526 int pending_del_nr = 0; 4527 int pending_del_slot = 0; 4528 int extent_type = -1; 4529 int ret; 4530 u64 ino = btrfs_ino(BTRFS_I(inode)); 4531 u64 bytes_deleted = 0; 4532 bool be_nice = false; 4533 bool should_throttle = false; 4534 bool should_end = false; 4535 4536 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); 4537 4538 /* 4539 * for non-free space inodes and ref cows, we want to back off from 4540 * time to time 4541 */ 4542 if (!btrfs_is_free_space_inode(BTRFS_I(inode)) && 4543 test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4544 be_nice = true; 4545 4546 path = btrfs_alloc_path(); 4547 if (!path) 4548 return -ENOMEM; 4549 path->reada = READA_BACK; 4550 4551 /* 4552 * We want to drop from the next block forward in case this new size is 4553 * not block aligned since we will be keeping the last block of the 4554 * extent just the way it is. 4555 */ 4556 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || 4557 root == fs_info->tree_root) 4558 btrfs_drop_extent_cache(BTRFS_I(inode), ALIGN(new_size, 4559 fs_info->sectorsize), 4560 (u64)-1, 0); 4561 4562 /* 4563 * This function is also used to drop the items in the log tree before 4564 * we relog the inode, so if root != BTRFS_I(inode)->root, it means 4565 * it is used to drop the loged items. So we shouldn't kill the delayed 4566 * items. 4567 */ 4568 if (min_type == 0 && root == BTRFS_I(inode)->root) 4569 btrfs_kill_delayed_inode_items(BTRFS_I(inode)); 4570 4571 key.objectid = ino; 4572 key.offset = (u64)-1; 4573 key.type = (u8)-1; 4574 4575 search_again: 4576 /* 4577 * with a 16K leaf size and 128MB extents, you can actually queue 4578 * up a huge file in a single leaf. Most of the time that 4579 * bytes_deleted is > 0, it will be huge by the time we get here 4580 */ 4581 if (be_nice && bytes_deleted > SZ_32M && 4582 btrfs_should_end_transaction(trans)) { 4583 ret = -EAGAIN; 4584 goto out; 4585 } 4586 4587 path->leave_spinning = 1; 4588 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 4589 if (ret < 0) 4590 goto out; 4591 4592 if (ret > 0) { 4593 ret = 0; 4594 /* there are no items in the tree for us to truncate, we're 4595 * done 4596 */ 4597 if (path->slots[0] == 0) 4598 goto out; 4599 path->slots[0]--; 4600 } 4601 4602 while (1) { 4603 fi = NULL; 4604 leaf = path->nodes[0]; 4605 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 4606 found_type = found_key.type; 4607 4608 if (found_key.objectid != ino) 4609 break; 4610 4611 if (found_type < min_type) 4612 break; 4613 4614 item_end = found_key.offset; 4615 if (found_type == BTRFS_EXTENT_DATA_KEY) { 4616 fi = btrfs_item_ptr(leaf, path->slots[0], 4617 struct btrfs_file_extent_item); 4618 extent_type = btrfs_file_extent_type(leaf, fi); 4619 if (extent_type != BTRFS_FILE_EXTENT_INLINE) { 4620 item_end += 4621 btrfs_file_extent_num_bytes(leaf, fi); 4622 4623 trace_btrfs_truncate_show_fi_regular( 4624 BTRFS_I(inode), leaf, fi, 4625 found_key.offset); 4626 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 4627 item_end += btrfs_file_extent_ram_bytes(leaf, 4628 fi); 4629 4630 trace_btrfs_truncate_show_fi_inline( 4631 BTRFS_I(inode), leaf, fi, path->slots[0], 4632 found_key.offset); 4633 } 4634 item_end--; 4635 } 4636 if (found_type > min_type) { 4637 del_item = 1; 4638 } else { 4639 if (item_end < new_size) 4640 break; 4641 if (found_key.offset >= new_size) 4642 del_item = 1; 4643 else 4644 del_item = 0; 4645 } 4646 found_extent = 0; 4647 /* FIXME, shrink the extent if the ref count is only 1 */ 4648 if (found_type != BTRFS_EXTENT_DATA_KEY) 4649 goto delete; 4650 4651 if (extent_type != BTRFS_FILE_EXTENT_INLINE) { 4652 u64 num_dec; 4653 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi); 4654 if (!del_item) { 4655 u64 orig_num_bytes = 4656 btrfs_file_extent_num_bytes(leaf, fi); 4657 extent_num_bytes = ALIGN(new_size - 4658 found_key.offset, 4659 fs_info->sectorsize); 4660 btrfs_set_file_extent_num_bytes(leaf, fi, 4661 extent_num_bytes); 4662 num_dec = (orig_num_bytes - 4663 extent_num_bytes); 4664 if (test_bit(BTRFS_ROOT_REF_COWS, 4665 &root->state) && 4666 extent_start != 0) 4667 inode_sub_bytes(inode, num_dec); 4668 btrfs_mark_buffer_dirty(leaf); 4669 } else { 4670 extent_num_bytes = 4671 btrfs_file_extent_disk_num_bytes(leaf, 4672 fi); 4673 extent_offset = found_key.offset - 4674 btrfs_file_extent_offset(leaf, fi); 4675 4676 /* FIXME blocksize != 4096 */ 4677 num_dec = btrfs_file_extent_num_bytes(leaf, fi); 4678 if (extent_start != 0) { 4679 found_extent = 1; 4680 if (test_bit(BTRFS_ROOT_REF_COWS, 4681 &root->state)) 4682 inode_sub_bytes(inode, num_dec); 4683 } 4684 } 4685 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { 4686 /* 4687 * we can't truncate inline items that have had 4688 * special encodings 4689 */ 4690 if (!del_item && 4691 btrfs_file_extent_encryption(leaf, fi) == 0 && 4692 btrfs_file_extent_other_encoding(leaf, fi) == 0 && 4693 btrfs_file_extent_compression(leaf, fi) == 0) { 4694 u32 size = (u32)(new_size - found_key.offset); 4695 4696 btrfs_set_file_extent_ram_bytes(leaf, fi, size); 4697 size = btrfs_file_extent_calc_inline_size(size); 4698 btrfs_truncate_item(root->fs_info, path, size, 1); 4699 } else if (!del_item) { 4700 /* 4701 * We have to bail so the last_size is set to 4702 * just before this extent. 4703 */ 4704 ret = NEED_TRUNCATE_BLOCK; 4705 break; 4706 } 4707 4708 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4709 inode_sub_bytes(inode, item_end + 1 - new_size); 4710 } 4711 delete: 4712 if (del_item) 4713 last_size = found_key.offset; 4714 else 4715 last_size = new_size; 4716 if (del_item) { 4717 if (!pending_del_nr) { 4718 /* no pending yet, add ourselves */ 4719 pending_del_slot = path->slots[0]; 4720 pending_del_nr = 1; 4721 } else if (pending_del_nr && 4722 path->slots[0] + 1 == pending_del_slot) { 4723 /* hop on the pending chunk */ 4724 pending_del_nr++; 4725 pending_del_slot = path->slots[0]; 4726 } else { 4727 BUG(); 4728 } 4729 } else { 4730 break; 4731 } 4732 should_throttle = false; 4733 4734 if (found_extent && 4735 (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || 4736 root == fs_info->tree_root)) { 4737 btrfs_set_path_blocking(path); 4738 bytes_deleted += extent_num_bytes; 4739 ret = btrfs_free_extent(trans, root, extent_start, 4740 extent_num_bytes, 0, 4741 btrfs_header_owner(leaf), 4742 ino, extent_offset); 4743 if (ret) { 4744 btrfs_abort_transaction(trans, ret); 4745 break; 4746 } 4747 if (btrfs_should_throttle_delayed_refs(trans, fs_info)) 4748 btrfs_async_run_delayed_refs(fs_info, 4749 trans->delayed_ref_updates * 2, 4750 trans->transid, 0); 4751 if (be_nice) { 4752 if (truncate_space_check(trans, root, 4753 extent_num_bytes)) { 4754 should_end = true; 4755 } 4756 if (btrfs_should_throttle_delayed_refs(trans, 4757 fs_info)) 4758 should_throttle = true; 4759 } 4760 } 4761 4762 if (found_type == BTRFS_INODE_ITEM_KEY) 4763 break; 4764 4765 if (path->slots[0] == 0 || 4766 path->slots[0] != pending_del_slot || 4767 should_throttle || should_end) { 4768 if (pending_del_nr) { 4769 ret = btrfs_del_items(trans, root, path, 4770 pending_del_slot, 4771 pending_del_nr); 4772 if (ret) { 4773 btrfs_abort_transaction(trans, ret); 4774 break; 4775 } 4776 pending_del_nr = 0; 4777 } 4778 btrfs_release_path(path); 4779 if (should_throttle) { 4780 unsigned long updates = trans->delayed_ref_updates; 4781 if (updates) { 4782 trans->delayed_ref_updates = 0; 4783 ret = btrfs_run_delayed_refs(trans, 4784 updates * 2); 4785 if (ret) 4786 break; 4787 } 4788 } 4789 /* 4790 * if we failed to refill our space rsv, bail out 4791 * and let the transaction restart 4792 */ 4793 if (should_end) { 4794 ret = -EAGAIN; 4795 break; 4796 } 4797 goto search_again; 4798 } else { 4799 path->slots[0]--; 4800 } 4801 } 4802 out: 4803 if (ret >= 0 && pending_del_nr) { 4804 int err; 4805 4806 err = btrfs_del_items(trans, root, path, pending_del_slot, 4807 pending_del_nr); 4808 if (err) { 4809 btrfs_abort_transaction(trans, err); 4810 ret = err; 4811 } 4812 } 4813 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { 4814 ASSERT(last_size >= new_size); 4815 if (!ret && last_size > new_size) 4816 last_size = new_size; 4817 btrfs_ordered_update_i_size(inode, last_size, NULL); 4818 } 4819 4820 btrfs_free_path(path); 4821 4822 if (be_nice && bytes_deleted > SZ_32M && (ret >= 0 || ret == -EAGAIN)) { 4823 unsigned long updates = trans->delayed_ref_updates; 4824 int err; 4825 4826 if (updates) { 4827 trans->delayed_ref_updates = 0; 4828 err = btrfs_run_delayed_refs(trans, updates * 2); 4829 if (err) 4830 ret = err; 4831 } 4832 } 4833 return ret; 4834 } 4835 4836 /* 4837 * btrfs_truncate_block - read, zero a chunk and write a block 4838 * @inode - inode that we're zeroing 4839 * @from - the offset to start zeroing 4840 * @len - the length to zero, 0 to zero the entire range respective to the 4841 * offset 4842 * @front - zero up to the offset instead of from the offset on 4843 * 4844 * This will find the block for the "from" offset and cow the block and zero the 4845 * part we want to zero. This is used with truncate and hole punching. 4846 */ 4847 int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len, 4848 int front) 4849 { 4850 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 4851 struct address_space *mapping = inode->i_mapping; 4852 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 4853 struct btrfs_ordered_extent *ordered; 4854 struct extent_state *cached_state = NULL; 4855 struct extent_changeset *data_reserved = NULL; 4856 char *kaddr; 4857 u32 blocksize = fs_info->sectorsize; 4858 pgoff_t index = from >> PAGE_SHIFT; 4859 unsigned offset = from & (blocksize - 1); 4860 struct page *page; 4861 gfp_t mask = btrfs_alloc_write_mask(mapping); 4862 int ret = 0; 4863 u64 block_start; 4864 u64 block_end; 4865 4866 if (IS_ALIGNED(offset, blocksize) && 4867 (!len || IS_ALIGNED(len, blocksize))) 4868 goto out; 4869 4870 block_start = round_down(from, blocksize); 4871 block_end = block_start + blocksize - 1; 4872 4873 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, 4874 block_start, blocksize); 4875 if (ret) 4876 goto out; 4877 4878 again: 4879 page = find_or_create_page(mapping, index, mask); 4880 if (!page) { 4881 btrfs_delalloc_release_space(inode, data_reserved, 4882 block_start, blocksize, true); 4883 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true); 4884 ret = -ENOMEM; 4885 goto out; 4886 } 4887 4888 if (!PageUptodate(page)) { 4889 ret = btrfs_readpage(NULL, page); 4890 lock_page(page); 4891 if (page->mapping != mapping) { 4892 unlock_page(page); 4893 put_page(page); 4894 goto again; 4895 } 4896 if (!PageUptodate(page)) { 4897 ret = -EIO; 4898 goto out_unlock; 4899 } 4900 } 4901 wait_on_page_writeback(page); 4902 4903 lock_extent_bits(io_tree, block_start, block_end, &cached_state); 4904 set_page_extent_mapped(page); 4905 4906 ordered = btrfs_lookup_ordered_extent(inode, block_start); 4907 if (ordered) { 4908 unlock_extent_cached(io_tree, block_start, block_end, 4909 &cached_state); 4910 unlock_page(page); 4911 put_page(page); 4912 btrfs_start_ordered_extent(inode, ordered, 1); 4913 btrfs_put_ordered_extent(ordered); 4914 goto again; 4915 } 4916 4917 clear_extent_bit(&BTRFS_I(inode)->io_tree, block_start, block_end, 4918 EXTENT_DIRTY | EXTENT_DELALLOC | 4919 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 4920 0, 0, &cached_state); 4921 4922 ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 0, 4923 &cached_state, 0); 4924 if (ret) { 4925 unlock_extent_cached(io_tree, block_start, block_end, 4926 &cached_state); 4927 goto out_unlock; 4928 } 4929 4930 if (offset != blocksize) { 4931 if (!len) 4932 len = blocksize - offset; 4933 kaddr = kmap(page); 4934 if (front) 4935 memset(kaddr + (block_start - page_offset(page)), 4936 0, offset); 4937 else 4938 memset(kaddr + (block_start - page_offset(page)) + offset, 4939 0, len); 4940 flush_dcache_page(page); 4941 kunmap(page); 4942 } 4943 ClearPageChecked(page); 4944 set_page_dirty(page); 4945 unlock_extent_cached(io_tree, block_start, block_end, &cached_state); 4946 4947 out_unlock: 4948 if (ret) 4949 btrfs_delalloc_release_space(inode, data_reserved, block_start, 4950 blocksize, true); 4951 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, (ret != 0)); 4952 unlock_page(page); 4953 put_page(page); 4954 out: 4955 extent_changeset_free(data_reserved); 4956 return ret; 4957 } 4958 4959 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode, 4960 u64 offset, u64 len) 4961 { 4962 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 4963 struct btrfs_trans_handle *trans; 4964 int ret; 4965 4966 /* 4967 * Still need to make sure the inode looks like it's been updated so 4968 * that any holes get logged if we fsync. 4969 */ 4970 if (btrfs_fs_incompat(fs_info, NO_HOLES)) { 4971 BTRFS_I(inode)->last_trans = fs_info->generation; 4972 BTRFS_I(inode)->last_sub_trans = root->log_transid; 4973 BTRFS_I(inode)->last_log_commit = root->last_log_commit; 4974 return 0; 4975 } 4976 4977 /* 4978 * 1 - for the one we're dropping 4979 * 1 - for the one we're adding 4980 * 1 - for updating the inode. 4981 */ 4982 trans = btrfs_start_transaction(root, 3); 4983 if (IS_ERR(trans)) 4984 return PTR_ERR(trans); 4985 4986 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1); 4987 if (ret) { 4988 btrfs_abort_transaction(trans, ret); 4989 btrfs_end_transaction(trans); 4990 return ret; 4991 } 4992 4993 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(BTRFS_I(inode)), 4994 offset, 0, 0, len, 0, len, 0, 0, 0); 4995 if (ret) 4996 btrfs_abort_transaction(trans, ret); 4997 else 4998 btrfs_update_inode(trans, root, inode); 4999 btrfs_end_transaction(trans); 5000 return ret; 5001 } 5002 5003 /* 5004 * This function puts in dummy file extents for the area we're creating a hole 5005 * for. So if we are truncating this file to a larger size we need to insert 5006 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for 5007 * the range between oldsize and size 5008 */ 5009 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size) 5010 { 5011 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5012 struct btrfs_root *root = BTRFS_I(inode)->root; 5013 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 5014 struct extent_map *em = NULL; 5015 struct extent_state *cached_state = NULL; 5016 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 5017 u64 hole_start = ALIGN(oldsize, fs_info->sectorsize); 5018 u64 block_end = ALIGN(size, fs_info->sectorsize); 5019 u64 last_byte; 5020 u64 cur_offset; 5021 u64 hole_size; 5022 int err = 0; 5023 5024 /* 5025 * If our size started in the middle of a block we need to zero out the 5026 * rest of the block before we expand the i_size, otherwise we could 5027 * expose stale data. 5028 */ 5029 err = btrfs_truncate_block(inode, oldsize, 0, 0); 5030 if (err) 5031 return err; 5032 5033 if (size <= hole_start) 5034 return 0; 5035 5036 while (1) { 5037 struct btrfs_ordered_extent *ordered; 5038 5039 lock_extent_bits(io_tree, hole_start, block_end - 1, 5040 &cached_state); 5041 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), hole_start, 5042 block_end - hole_start); 5043 if (!ordered) 5044 break; 5045 unlock_extent_cached(io_tree, hole_start, block_end - 1, 5046 &cached_state); 5047 btrfs_start_ordered_extent(inode, ordered, 1); 5048 btrfs_put_ordered_extent(ordered); 5049 } 5050 5051 cur_offset = hole_start; 5052 while (1) { 5053 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset, 5054 block_end - cur_offset, 0); 5055 if (IS_ERR(em)) { 5056 err = PTR_ERR(em); 5057 em = NULL; 5058 break; 5059 } 5060 last_byte = min(extent_map_end(em), block_end); 5061 last_byte = ALIGN(last_byte, fs_info->sectorsize); 5062 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) { 5063 struct extent_map *hole_em; 5064 hole_size = last_byte - cur_offset; 5065 5066 err = maybe_insert_hole(root, inode, cur_offset, 5067 hole_size); 5068 if (err) 5069 break; 5070 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, 5071 cur_offset + hole_size - 1, 0); 5072 hole_em = alloc_extent_map(); 5073 if (!hole_em) { 5074 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 5075 &BTRFS_I(inode)->runtime_flags); 5076 goto next; 5077 } 5078 hole_em->start = cur_offset; 5079 hole_em->len = hole_size; 5080 hole_em->orig_start = cur_offset; 5081 5082 hole_em->block_start = EXTENT_MAP_HOLE; 5083 hole_em->block_len = 0; 5084 hole_em->orig_block_len = 0; 5085 hole_em->ram_bytes = hole_size; 5086 hole_em->bdev = fs_info->fs_devices->latest_bdev; 5087 hole_em->compress_type = BTRFS_COMPRESS_NONE; 5088 hole_em->generation = fs_info->generation; 5089 5090 while (1) { 5091 write_lock(&em_tree->lock); 5092 err = add_extent_mapping(em_tree, hole_em, 1); 5093 write_unlock(&em_tree->lock); 5094 if (err != -EEXIST) 5095 break; 5096 btrfs_drop_extent_cache(BTRFS_I(inode), 5097 cur_offset, 5098 cur_offset + 5099 hole_size - 1, 0); 5100 } 5101 free_extent_map(hole_em); 5102 } 5103 next: 5104 free_extent_map(em); 5105 em = NULL; 5106 cur_offset = last_byte; 5107 if (cur_offset >= block_end) 5108 break; 5109 } 5110 free_extent_map(em); 5111 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state); 5112 return err; 5113 } 5114 5115 static int btrfs_setsize(struct inode *inode, struct iattr *attr) 5116 { 5117 struct btrfs_root *root = BTRFS_I(inode)->root; 5118 struct btrfs_trans_handle *trans; 5119 loff_t oldsize = i_size_read(inode); 5120 loff_t newsize = attr->ia_size; 5121 int mask = attr->ia_valid; 5122 int ret; 5123 5124 /* 5125 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a 5126 * special case where we need to update the times despite not having 5127 * these flags set. For all other operations the VFS set these flags 5128 * explicitly if it wants a timestamp update. 5129 */ 5130 if (newsize != oldsize) { 5131 inode_inc_iversion(inode); 5132 if (!(mask & (ATTR_CTIME | ATTR_MTIME))) 5133 inode->i_ctime = inode->i_mtime = 5134 current_time(inode); 5135 } 5136 5137 if (newsize > oldsize) { 5138 /* 5139 * Don't do an expanding truncate while snapshotting is ongoing. 5140 * This is to ensure the snapshot captures a fully consistent 5141 * state of this file - if the snapshot captures this expanding 5142 * truncation, it must capture all writes that happened before 5143 * this truncation. 5144 */ 5145 btrfs_wait_for_snapshot_creation(root); 5146 ret = btrfs_cont_expand(inode, oldsize, newsize); 5147 if (ret) { 5148 btrfs_end_write_no_snapshotting(root); 5149 return ret; 5150 } 5151 5152 trans = btrfs_start_transaction(root, 1); 5153 if (IS_ERR(trans)) { 5154 btrfs_end_write_no_snapshotting(root); 5155 return PTR_ERR(trans); 5156 } 5157 5158 i_size_write(inode, newsize); 5159 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL); 5160 pagecache_isize_extended(inode, oldsize, newsize); 5161 ret = btrfs_update_inode(trans, root, inode); 5162 btrfs_end_write_no_snapshotting(root); 5163 btrfs_end_transaction(trans); 5164 } else { 5165 5166 /* 5167 * We're truncating a file that used to have good data down to 5168 * zero. Make sure it gets into the ordered flush list so that 5169 * any new writes get down to disk quickly. 5170 */ 5171 if (newsize == 0) 5172 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE, 5173 &BTRFS_I(inode)->runtime_flags); 5174 5175 truncate_setsize(inode, newsize); 5176 5177 /* Disable nonlocked read DIO to avoid the end less truncate */ 5178 btrfs_inode_block_unlocked_dio(BTRFS_I(inode)); 5179 inode_dio_wait(inode); 5180 btrfs_inode_resume_unlocked_dio(BTRFS_I(inode)); 5181 5182 ret = btrfs_truncate(inode, newsize == oldsize); 5183 if (ret && inode->i_nlink) { 5184 int err; 5185 5186 /* 5187 * Truncate failed, so fix up the in-memory size. We 5188 * adjusted disk_i_size down as we removed extents, so 5189 * wait for disk_i_size to be stable and then update the 5190 * in-memory size to match. 5191 */ 5192 err = btrfs_wait_ordered_range(inode, 0, (u64)-1); 5193 if (err) 5194 return err; 5195 i_size_write(inode, BTRFS_I(inode)->disk_i_size); 5196 } 5197 } 5198 5199 return ret; 5200 } 5201 5202 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) 5203 { 5204 struct inode *inode = d_inode(dentry); 5205 struct btrfs_root *root = BTRFS_I(inode)->root; 5206 int err; 5207 5208 if (btrfs_root_readonly(root)) 5209 return -EROFS; 5210 5211 err = setattr_prepare(dentry, attr); 5212 if (err) 5213 return err; 5214 5215 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { 5216 err = btrfs_setsize(inode, attr); 5217 if (err) 5218 return err; 5219 } 5220 5221 if (attr->ia_valid) { 5222 setattr_copy(inode, attr); 5223 inode_inc_iversion(inode); 5224 err = btrfs_dirty_inode(inode); 5225 5226 if (!err && attr->ia_valid & ATTR_MODE) 5227 err = posix_acl_chmod(inode, inode->i_mode); 5228 } 5229 5230 return err; 5231 } 5232 5233 /* 5234 * While truncating the inode pages during eviction, we get the VFS calling 5235 * btrfs_invalidatepage() against each page of the inode. This is slow because 5236 * the calls to btrfs_invalidatepage() result in a huge amount of calls to 5237 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting 5238 * extent_state structures over and over, wasting lots of time. 5239 * 5240 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all 5241 * those expensive operations on a per page basis and do only the ordered io 5242 * finishing, while we release here the extent_map and extent_state structures, 5243 * without the excessive merging and splitting. 5244 */ 5245 static void evict_inode_truncate_pages(struct inode *inode) 5246 { 5247 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 5248 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree; 5249 struct rb_node *node; 5250 5251 ASSERT(inode->i_state & I_FREEING); 5252 truncate_inode_pages_final(&inode->i_data); 5253 5254 write_lock(&map_tree->lock); 5255 while (!RB_EMPTY_ROOT(&map_tree->map)) { 5256 struct extent_map *em; 5257 5258 node = rb_first(&map_tree->map); 5259 em = rb_entry(node, struct extent_map, rb_node); 5260 clear_bit(EXTENT_FLAG_PINNED, &em->flags); 5261 clear_bit(EXTENT_FLAG_LOGGING, &em->flags); 5262 remove_extent_mapping(map_tree, em); 5263 free_extent_map(em); 5264 if (need_resched()) { 5265 write_unlock(&map_tree->lock); 5266 cond_resched(); 5267 write_lock(&map_tree->lock); 5268 } 5269 } 5270 write_unlock(&map_tree->lock); 5271 5272 /* 5273 * Keep looping until we have no more ranges in the io tree. 5274 * We can have ongoing bios started by readpages (called from readahead) 5275 * that have their endio callback (extent_io.c:end_bio_extent_readpage) 5276 * still in progress (unlocked the pages in the bio but did not yet 5277 * unlocked the ranges in the io tree). Therefore this means some 5278 * ranges can still be locked and eviction started because before 5279 * submitting those bios, which are executed by a separate task (work 5280 * queue kthread), inode references (inode->i_count) were not taken 5281 * (which would be dropped in the end io callback of each bio). 5282 * Therefore here we effectively end up waiting for those bios and 5283 * anyone else holding locked ranges without having bumped the inode's 5284 * reference count - if we don't do it, when they access the inode's 5285 * io_tree to unlock a range it may be too late, leading to an 5286 * use-after-free issue. 5287 */ 5288 spin_lock(&io_tree->lock); 5289 while (!RB_EMPTY_ROOT(&io_tree->state)) { 5290 struct extent_state *state; 5291 struct extent_state *cached_state = NULL; 5292 u64 start; 5293 u64 end; 5294 5295 node = rb_first(&io_tree->state); 5296 state = rb_entry(node, struct extent_state, rb_node); 5297 start = state->start; 5298 end = state->end; 5299 spin_unlock(&io_tree->lock); 5300 5301 lock_extent_bits(io_tree, start, end, &cached_state); 5302 5303 /* 5304 * If still has DELALLOC flag, the extent didn't reach disk, 5305 * and its reserved space won't be freed by delayed_ref. 5306 * So we need to free its reserved space here. 5307 * (Refer to comment in btrfs_invalidatepage, case 2) 5308 * 5309 * Note, end is the bytenr of last byte, so we need + 1 here. 5310 */ 5311 if (state->state & EXTENT_DELALLOC) 5312 btrfs_qgroup_free_data(inode, NULL, start, end - start + 1); 5313 5314 clear_extent_bit(io_tree, start, end, 5315 EXTENT_LOCKED | EXTENT_DIRTY | 5316 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | 5317 EXTENT_DEFRAG, 1, 1, &cached_state); 5318 5319 cond_resched(); 5320 spin_lock(&io_tree->lock); 5321 } 5322 spin_unlock(&io_tree->lock); 5323 } 5324 5325 static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root, 5326 struct btrfs_block_rsv *rsv, 5327 u64 min_size) 5328 { 5329 struct btrfs_fs_info *fs_info = root->fs_info; 5330 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; 5331 int failures = 0; 5332 5333 for (;;) { 5334 struct btrfs_trans_handle *trans; 5335 int ret; 5336 5337 ret = btrfs_block_rsv_refill(root, rsv, min_size, 5338 BTRFS_RESERVE_FLUSH_LIMIT); 5339 5340 if (ret && ++failures > 2) { 5341 btrfs_warn(fs_info, 5342 "could not allocate space for a delete; will truncate on mount"); 5343 return ERR_PTR(-ENOSPC); 5344 } 5345 5346 trans = btrfs_join_transaction(root); 5347 if (IS_ERR(trans) || !ret) 5348 return trans; 5349 5350 /* 5351 * Try to steal from the global reserve if there is space for 5352 * it. 5353 */ 5354 if (!btrfs_check_space_for_delayed_refs(trans, fs_info) && 5355 !btrfs_block_rsv_migrate(global_rsv, rsv, min_size, 0)) 5356 return trans; 5357 5358 /* If not, commit and try again. */ 5359 ret = btrfs_commit_transaction(trans); 5360 if (ret) 5361 return ERR_PTR(ret); 5362 } 5363 } 5364 5365 void btrfs_evict_inode(struct inode *inode) 5366 { 5367 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5368 struct btrfs_trans_handle *trans; 5369 struct btrfs_root *root = BTRFS_I(inode)->root; 5370 struct btrfs_block_rsv *rsv; 5371 u64 min_size; 5372 int ret; 5373 5374 trace_btrfs_inode_evict(inode); 5375 5376 if (!root) { 5377 clear_inode(inode); 5378 return; 5379 } 5380 5381 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1); 5382 5383 evict_inode_truncate_pages(inode); 5384 5385 if (inode->i_nlink && 5386 ((btrfs_root_refs(&root->root_item) != 0 && 5387 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) || 5388 btrfs_is_free_space_inode(BTRFS_I(inode)))) 5389 goto no_delete; 5390 5391 if (is_bad_inode(inode)) 5392 goto no_delete; 5393 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */ 5394 if (!special_file(inode->i_mode)) 5395 btrfs_wait_ordered_range(inode, 0, (u64)-1); 5396 5397 btrfs_free_io_failure_record(BTRFS_I(inode), 0, (u64)-1); 5398 5399 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) 5400 goto no_delete; 5401 5402 if (inode->i_nlink > 0) { 5403 BUG_ON(btrfs_root_refs(&root->root_item) != 0 && 5404 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID); 5405 goto no_delete; 5406 } 5407 5408 ret = btrfs_commit_inode_delayed_inode(BTRFS_I(inode)); 5409 if (ret) 5410 goto no_delete; 5411 5412 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); 5413 if (!rsv) 5414 goto no_delete; 5415 rsv->size = min_size; 5416 rsv->failfast = 1; 5417 5418 btrfs_i_size_write(BTRFS_I(inode), 0); 5419 5420 while (1) { 5421 trans = evict_refill_and_join(root, rsv, min_size); 5422 if (IS_ERR(trans)) 5423 goto free_rsv; 5424 5425 trans->block_rsv = rsv; 5426 5427 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0); 5428 trans->block_rsv = &fs_info->trans_block_rsv; 5429 btrfs_end_transaction(trans); 5430 btrfs_btree_balance_dirty(fs_info); 5431 if (ret && ret != -ENOSPC && ret != -EAGAIN) 5432 goto free_rsv; 5433 else if (!ret) 5434 break; 5435 } 5436 5437 /* 5438 * Errors here aren't a big deal, it just means we leave orphan items in 5439 * the tree. They will be cleaned up on the next mount. If the inode 5440 * number gets reused, cleanup deletes the orphan item without doing 5441 * anything, and unlink reuses the existing orphan item. 5442 * 5443 * If it turns out that we are dropping too many of these, we might want 5444 * to add a mechanism for retrying these after a commit. 5445 */ 5446 trans = evict_refill_and_join(root, rsv, min_size); 5447 if (!IS_ERR(trans)) { 5448 trans->block_rsv = rsv; 5449 btrfs_orphan_del(trans, BTRFS_I(inode)); 5450 trans->block_rsv = &fs_info->trans_block_rsv; 5451 btrfs_end_transaction(trans); 5452 } 5453 5454 if (!(root == fs_info->tree_root || 5455 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)) 5456 btrfs_return_ino(root, btrfs_ino(BTRFS_I(inode))); 5457 5458 free_rsv: 5459 btrfs_free_block_rsv(fs_info, rsv); 5460 no_delete: 5461 /* 5462 * If we didn't successfully delete, the orphan item will still be in 5463 * the tree and we'll retry on the next mount. Again, we might also want 5464 * to retry these periodically in the future. 5465 */ 5466 btrfs_remove_delayed_node(BTRFS_I(inode)); 5467 clear_inode(inode); 5468 } 5469 5470 /* 5471 * this returns the key found in the dir entry in the location pointer. 5472 * If no dir entries were found, returns -ENOENT. 5473 * If found a corrupted location in dir entry, returns -EUCLEAN. 5474 */ 5475 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, 5476 struct btrfs_key *location) 5477 { 5478 const char *name = dentry->d_name.name; 5479 int namelen = dentry->d_name.len; 5480 struct btrfs_dir_item *di; 5481 struct btrfs_path *path; 5482 struct btrfs_root *root = BTRFS_I(dir)->root; 5483 int ret = 0; 5484 5485 path = btrfs_alloc_path(); 5486 if (!path) 5487 return -ENOMEM; 5488 5489 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(BTRFS_I(dir)), 5490 name, namelen, 0); 5491 if (!di) { 5492 ret = -ENOENT; 5493 goto out; 5494 } 5495 if (IS_ERR(di)) { 5496 ret = PTR_ERR(di); 5497 goto out; 5498 } 5499 5500 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); 5501 if (location->type != BTRFS_INODE_ITEM_KEY && 5502 location->type != BTRFS_ROOT_ITEM_KEY) { 5503 ret = -EUCLEAN; 5504 btrfs_warn(root->fs_info, 5505 "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))", 5506 __func__, name, btrfs_ino(BTRFS_I(dir)), 5507 location->objectid, location->type, location->offset); 5508 } 5509 out: 5510 btrfs_free_path(path); 5511 return ret; 5512 } 5513 5514 /* 5515 * when we hit a tree root in a directory, the btrfs part of the inode 5516 * needs to be changed to reflect the root directory of the tree root. This 5517 * is kind of like crossing a mount point. 5518 */ 5519 static int fixup_tree_root_location(struct btrfs_fs_info *fs_info, 5520 struct inode *dir, 5521 struct dentry *dentry, 5522 struct btrfs_key *location, 5523 struct btrfs_root **sub_root) 5524 { 5525 struct btrfs_path *path; 5526 struct btrfs_root *new_root; 5527 struct btrfs_root_ref *ref; 5528 struct extent_buffer *leaf; 5529 struct btrfs_key key; 5530 int ret; 5531 int err = 0; 5532 5533 path = btrfs_alloc_path(); 5534 if (!path) { 5535 err = -ENOMEM; 5536 goto out; 5537 } 5538 5539 err = -ENOENT; 5540 key.objectid = BTRFS_I(dir)->root->root_key.objectid; 5541 key.type = BTRFS_ROOT_REF_KEY; 5542 key.offset = location->objectid; 5543 5544 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 5545 if (ret) { 5546 if (ret < 0) 5547 err = ret; 5548 goto out; 5549 } 5550 5551 leaf = path->nodes[0]; 5552 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); 5553 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(BTRFS_I(dir)) || 5554 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len) 5555 goto out; 5556 5557 ret = memcmp_extent_buffer(leaf, dentry->d_name.name, 5558 (unsigned long)(ref + 1), 5559 dentry->d_name.len); 5560 if (ret) 5561 goto out; 5562 5563 btrfs_release_path(path); 5564 5565 new_root = btrfs_read_fs_root_no_name(fs_info, location); 5566 if (IS_ERR(new_root)) { 5567 err = PTR_ERR(new_root); 5568 goto out; 5569 } 5570 5571 *sub_root = new_root; 5572 location->objectid = btrfs_root_dirid(&new_root->root_item); 5573 location->type = BTRFS_INODE_ITEM_KEY; 5574 location->offset = 0; 5575 err = 0; 5576 out: 5577 btrfs_free_path(path); 5578 return err; 5579 } 5580 5581 static void inode_tree_add(struct inode *inode) 5582 { 5583 struct btrfs_root *root = BTRFS_I(inode)->root; 5584 struct btrfs_inode *entry; 5585 struct rb_node **p; 5586 struct rb_node *parent; 5587 struct rb_node *new = &BTRFS_I(inode)->rb_node; 5588 u64 ino = btrfs_ino(BTRFS_I(inode)); 5589 5590 if (inode_unhashed(inode)) 5591 return; 5592 parent = NULL; 5593 spin_lock(&root->inode_lock); 5594 p = &root->inode_tree.rb_node; 5595 while (*p) { 5596 parent = *p; 5597 entry = rb_entry(parent, struct btrfs_inode, rb_node); 5598 5599 if (ino < btrfs_ino(entry)) 5600 p = &parent->rb_left; 5601 else if (ino > btrfs_ino(entry)) 5602 p = &parent->rb_right; 5603 else { 5604 WARN_ON(!(entry->vfs_inode.i_state & 5605 (I_WILL_FREE | I_FREEING))); 5606 rb_replace_node(parent, new, &root->inode_tree); 5607 RB_CLEAR_NODE(parent); 5608 spin_unlock(&root->inode_lock); 5609 return; 5610 } 5611 } 5612 rb_link_node(new, parent, p); 5613 rb_insert_color(new, &root->inode_tree); 5614 spin_unlock(&root->inode_lock); 5615 } 5616 5617 static void inode_tree_del(struct inode *inode) 5618 { 5619 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 5620 struct btrfs_root *root = BTRFS_I(inode)->root; 5621 int empty = 0; 5622 5623 spin_lock(&root->inode_lock); 5624 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { 5625 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); 5626 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); 5627 empty = RB_EMPTY_ROOT(&root->inode_tree); 5628 } 5629 spin_unlock(&root->inode_lock); 5630 5631 if (empty && btrfs_root_refs(&root->root_item) == 0) { 5632 synchronize_srcu(&fs_info->subvol_srcu); 5633 spin_lock(&root->inode_lock); 5634 empty = RB_EMPTY_ROOT(&root->inode_tree); 5635 spin_unlock(&root->inode_lock); 5636 if (empty) 5637 btrfs_add_dead_root(root); 5638 } 5639 } 5640 5641 5642 static int btrfs_init_locked_inode(struct inode *inode, void *p) 5643 { 5644 struct btrfs_iget_args *args = p; 5645 inode->i_ino = args->location->objectid; 5646 memcpy(&BTRFS_I(inode)->location, args->location, 5647 sizeof(*args->location)); 5648 BTRFS_I(inode)->root = args->root; 5649 return 0; 5650 } 5651 5652 static int btrfs_find_actor(struct inode *inode, void *opaque) 5653 { 5654 struct btrfs_iget_args *args = opaque; 5655 return args->location->objectid == BTRFS_I(inode)->location.objectid && 5656 args->root == BTRFS_I(inode)->root; 5657 } 5658 5659 static struct inode *btrfs_iget_locked(struct super_block *s, 5660 struct btrfs_key *location, 5661 struct btrfs_root *root) 5662 { 5663 struct inode *inode; 5664 struct btrfs_iget_args args; 5665 unsigned long hashval = btrfs_inode_hash(location->objectid, root); 5666 5667 args.location = location; 5668 args.root = root; 5669 5670 inode = iget5_locked(s, hashval, btrfs_find_actor, 5671 btrfs_init_locked_inode, 5672 (void *)&args); 5673 return inode; 5674 } 5675 5676 /* Get an inode object given its location and corresponding root. 5677 * Returns in *is_new if the inode was read from disk 5678 */ 5679 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, 5680 struct btrfs_root *root, int *new) 5681 { 5682 struct inode *inode; 5683 5684 inode = btrfs_iget_locked(s, location, root); 5685 if (!inode) 5686 return ERR_PTR(-ENOMEM); 5687 5688 if (inode->i_state & I_NEW) { 5689 int ret; 5690 5691 ret = btrfs_read_locked_inode(inode); 5692 if (!ret) { 5693 inode_tree_add(inode); 5694 unlock_new_inode(inode); 5695 if (new) 5696 *new = 1; 5697 } else { 5698 iget_failed(inode); 5699 /* 5700 * ret > 0 can come from btrfs_search_slot called by 5701 * btrfs_read_locked_inode, this means the inode item 5702 * was not found. 5703 */ 5704 if (ret > 0) 5705 ret = -ENOENT; 5706 inode = ERR_PTR(ret); 5707 } 5708 } 5709 5710 return inode; 5711 } 5712 5713 static struct inode *new_simple_dir(struct super_block *s, 5714 struct btrfs_key *key, 5715 struct btrfs_root *root) 5716 { 5717 struct inode *inode = new_inode(s); 5718 5719 if (!inode) 5720 return ERR_PTR(-ENOMEM); 5721 5722 BTRFS_I(inode)->root = root; 5723 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key)); 5724 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags); 5725 5726 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID; 5727 inode->i_op = &btrfs_dir_ro_inode_operations; 5728 inode->i_opflags &= ~IOP_XATTR; 5729 inode->i_fop = &simple_dir_operations; 5730 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; 5731 inode->i_mtime = current_time(inode); 5732 inode->i_atime = inode->i_mtime; 5733 inode->i_ctime = inode->i_mtime; 5734 BTRFS_I(inode)->i_otime = inode->i_mtime; 5735 5736 return inode; 5737 } 5738 5739 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) 5740 { 5741 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 5742 struct inode *inode; 5743 struct btrfs_root *root = BTRFS_I(dir)->root; 5744 struct btrfs_root *sub_root = root; 5745 struct btrfs_key location; 5746 int index; 5747 int ret = 0; 5748 5749 if (dentry->d_name.len > BTRFS_NAME_LEN) 5750 return ERR_PTR(-ENAMETOOLONG); 5751 5752 ret = btrfs_inode_by_name(dir, dentry, &location); 5753 if (ret < 0) 5754 return ERR_PTR(ret); 5755 5756 if (location.type == BTRFS_INODE_ITEM_KEY) { 5757 inode = btrfs_iget(dir->i_sb, &location, root, NULL); 5758 return inode; 5759 } 5760 5761 index = srcu_read_lock(&fs_info->subvol_srcu); 5762 ret = fixup_tree_root_location(fs_info, dir, dentry, 5763 &location, &sub_root); 5764 if (ret < 0) { 5765 if (ret != -ENOENT) 5766 inode = ERR_PTR(ret); 5767 else 5768 inode = new_simple_dir(dir->i_sb, &location, sub_root); 5769 } else { 5770 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL); 5771 } 5772 srcu_read_unlock(&fs_info->subvol_srcu, index); 5773 5774 if (!IS_ERR(inode) && root != sub_root) { 5775 down_read(&fs_info->cleanup_work_sem); 5776 if (!sb_rdonly(inode->i_sb)) 5777 ret = btrfs_orphan_cleanup(sub_root); 5778 up_read(&fs_info->cleanup_work_sem); 5779 if (ret) { 5780 iput(inode); 5781 inode = ERR_PTR(ret); 5782 } 5783 } 5784 5785 return inode; 5786 } 5787 5788 static int btrfs_dentry_delete(const struct dentry *dentry) 5789 { 5790 struct btrfs_root *root; 5791 struct inode *inode = d_inode(dentry); 5792 5793 if (!inode && !IS_ROOT(dentry)) 5794 inode = d_inode(dentry->d_parent); 5795 5796 if (inode) { 5797 root = BTRFS_I(inode)->root; 5798 if (btrfs_root_refs(&root->root_item) == 0) 5799 return 1; 5800 5801 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) 5802 return 1; 5803 } 5804 return 0; 5805 } 5806 5807 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, 5808 unsigned int flags) 5809 { 5810 struct inode *inode; 5811 5812 inode = btrfs_lookup_dentry(dir, dentry); 5813 if (IS_ERR(inode)) { 5814 if (PTR_ERR(inode) == -ENOENT) 5815 inode = NULL; 5816 else 5817 return ERR_CAST(inode); 5818 } 5819 5820 return d_splice_alias(inode, dentry); 5821 } 5822 5823 unsigned char btrfs_filetype_table[] = { 5824 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK 5825 }; 5826 5827 /* 5828 * All this infrastructure exists because dir_emit can fault, and we are holding 5829 * the tree lock when doing readdir. For now just allocate a buffer and copy 5830 * our information into that, and then dir_emit from the buffer. This is 5831 * similar to what NFS does, only we don't keep the buffer around in pagecache 5832 * because I'm afraid I'll mess that up. Long term we need to make filldir do 5833 * copy_to_user_inatomic so we don't have to worry about page faulting under the 5834 * tree lock. 5835 */ 5836 static int btrfs_opendir(struct inode *inode, struct file *file) 5837 { 5838 struct btrfs_file_private *private; 5839 5840 private = kzalloc(sizeof(struct btrfs_file_private), GFP_KERNEL); 5841 if (!private) 5842 return -ENOMEM; 5843 private->filldir_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); 5844 if (!private->filldir_buf) { 5845 kfree(private); 5846 return -ENOMEM; 5847 } 5848 file->private_data = private; 5849 return 0; 5850 } 5851 5852 struct dir_entry { 5853 u64 ino; 5854 u64 offset; 5855 unsigned type; 5856 int name_len; 5857 }; 5858 5859 static int btrfs_filldir(void *addr, int entries, struct dir_context *ctx) 5860 { 5861 while (entries--) { 5862 struct dir_entry *entry = addr; 5863 char *name = (char *)(entry + 1); 5864 5865 ctx->pos = get_unaligned(&entry->offset); 5866 if (!dir_emit(ctx, name, get_unaligned(&entry->name_len), 5867 get_unaligned(&entry->ino), 5868 get_unaligned(&entry->type))) 5869 return 1; 5870 addr += sizeof(struct dir_entry) + 5871 get_unaligned(&entry->name_len); 5872 ctx->pos++; 5873 } 5874 return 0; 5875 } 5876 5877 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx) 5878 { 5879 struct inode *inode = file_inode(file); 5880 struct btrfs_root *root = BTRFS_I(inode)->root; 5881 struct btrfs_file_private *private = file->private_data; 5882 struct btrfs_dir_item *di; 5883 struct btrfs_key key; 5884 struct btrfs_key found_key; 5885 struct btrfs_path *path; 5886 void *addr; 5887 struct list_head ins_list; 5888 struct list_head del_list; 5889 int ret; 5890 struct extent_buffer *leaf; 5891 int slot; 5892 char *name_ptr; 5893 int name_len; 5894 int entries = 0; 5895 int total_len = 0; 5896 bool put = false; 5897 struct btrfs_key location; 5898 5899 if (!dir_emit_dots(file, ctx)) 5900 return 0; 5901 5902 path = btrfs_alloc_path(); 5903 if (!path) 5904 return -ENOMEM; 5905 5906 addr = private->filldir_buf; 5907 path->reada = READA_FORWARD; 5908 5909 INIT_LIST_HEAD(&ins_list); 5910 INIT_LIST_HEAD(&del_list); 5911 put = btrfs_readdir_get_delayed_items(inode, &ins_list, &del_list); 5912 5913 again: 5914 key.type = BTRFS_DIR_INDEX_KEY; 5915 key.offset = ctx->pos; 5916 key.objectid = btrfs_ino(BTRFS_I(inode)); 5917 5918 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5919 if (ret < 0) 5920 goto err; 5921 5922 while (1) { 5923 struct dir_entry *entry; 5924 5925 leaf = path->nodes[0]; 5926 slot = path->slots[0]; 5927 if (slot >= btrfs_header_nritems(leaf)) { 5928 ret = btrfs_next_leaf(root, path); 5929 if (ret < 0) 5930 goto err; 5931 else if (ret > 0) 5932 break; 5933 continue; 5934 } 5935 5936 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5937 5938 if (found_key.objectid != key.objectid) 5939 break; 5940 if (found_key.type != BTRFS_DIR_INDEX_KEY) 5941 break; 5942 if (found_key.offset < ctx->pos) 5943 goto next; 5944 if (btrfs_should_delete_dir_index(&del_list, found_key.offset)) 5945 goto next; 5946 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); 5947 name_len = btrfs_dir_name_len(leaf, di); 5948 if ((total_len + sizeof(struct dir_entry) + name_len) >= 5949 PAGE_SIZE) { 5950 btrfs_release_path(path); 5951 ret = btrfs_filldir(private->filldir_buf, entries, ctx); 5952 if (ret) 5953 goto nopos; 5954 addr = private->filldir_buf; 5955 entries = 0; 5956 total_len = 0; 5957 goto again; 5958 } 5959 5960 entry = addr; 5961 put_unaligned(name_len, &entry->name_len); 5962 name_ptr = (char *)(entry + 1); 5963 read_extent_buffer(leaf, name_ptr, (unsigned long)(di + 1), 5964 name_len); 5965 put_unaligned(btrfs_filetype_table[btrfs_dir_type(leaf, di)], 5966 &entry->type); 5967 btrfs_dir_item_key_to_cpu(leaf, di, &location); 5968 put_unaligned(location.objectid, &entry->ino); 5969 put_unaligned(found_key.offset, &entry->offset); 5970 entries++; 5971 addr += sizeof(struct dir_entry) + name_len; 5972 total_len += sizeof(struct dir_entry) + name_len; 5973 next: 5974 path->slots[0]++; 5975 } 5976 btrfs_release_path(path); 5977 5978 ret = btrfs_filldir(private->filldir_buf, entries, ctx); 5979 if (ret) 5980 goto nopos; 5981 5982 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list); 5983 if (ret) 5984 goto nopos; 5985 5986 /* 5987 * Stop new entries from being returned after we return the last 5988 * entry. 5989 * 5990 * New directory entries are assigned a strictly increasing 5991 * offset. This means that new entries created during readdir 5992 * are *guaranteed* to be seen in the future by that readdir. 5993 * This has broken buggy programs which operate on names as 5994 * they're returned by readdir. Until we re-use freed offsets 5995 * we have this hack to stop new entries from being returned 5996 * under the assumption that they'll never reach this huge 5997 * offset. 5998 * 5999 * This is being careful not to overflow 32bit loff_t unless the 6000 * last entry requires it because doing so has broken 32bit apps 6001 * in the past. 6002 */ 6003 if (ctx->pos >= INT_MAX) 6004 ctx->pos = LLONG_MAX; 6005 else 6006 ctx->pos = INT_MAX; 6007 nopos: 6008 ret = 0; 6009 err: 6010 if (put) 6011 btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list); 6012 btrfs_free_path(path); 6013 return ret; 6014 } 6015 6016 /* 6017 * This is somewhat expensive, updating the tree every time the 6018 * inode changes. But, it is most likely to find the inode in cache. 6019 * FIXME, needs more benchmarking...there are no reasons other than performance 6020 * to keep or drop this code. 6021 */ 6022 static int btrfs_dirty_inode(struct inode *inode) 6023 { 6024 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 6025 struct btrfs_root *root = BTRFS_I(inode)->root; 6026 struct btrfs_trans_handle *trans; 6027 int ret; 6028 6029 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags)) 6030 return 0; 6031 6032 trans = btrfs_join_transaction(root); 6033 if (IS_ERR(trans)) 6034 return PTR_ERR(trans); 6035 6036 ret = btrfs_update_inode(trans, root, inode); 6037 if (ret && ret == -ENOSPC) { 6038 /* whoops, lets try again with the full transaction */ 6039 btrfs_end_transaction(trans); 6040 trans = btrfs_start_transaction(root, 1); 6041 if (IS_ERR(trans)) 6042 return PTR_ERR(trans); 6043 6044 ret = btrfs_update_inode(trans, root, inode); 6045 } 6046 btrfs_end_transaction(trans); 6047 if (BTRFS_I(inode)->delayed_node) 6048 btrfs_balance_delayed_items(fs_info); 6049 6050 return ret; 6051 } 6052 6053 /* 6054 * This is a copy of file_update_time. We need this so we can return error on 6055 * ENOSPC for updating the inode in the case of file write and mmap writes. 6056 */ 6057 static int btrfs_update_time(struct inode *inode, struct timespec64 *now, 6058 int flags) 6059 { 6060 struct btrfs_root *root = BTRFS_I(inode)->root; 6061 bool dirty = flags & ~S_VERSION; 6062 6063 if (btrfs_root_readonly(root)) 6064 return -EROFS; 6065 6066 if (flags & S_VERSION) 6067 dirty |= inode_maybe_inc_iversion(inode, dirty); 6068 if (flags & S_CTIME) 6069 inode->i_ctime = *now; 6070 if (flags & S_MTIME) 6071 inode->i_mtime = *now; 6072 if (flags & S_ATIME) 6073 inode->i_atime = *now; 6074 return dirty ? btrfs_dirty_inode(inode) : 0; 6075 } 6076 6077 /* 6078 * find the highest existing sequence number in a directory 6079 * and then set the in-memory index_cnt variable to reflect 6080 * free sequence numbers 6081 */ 6082 static int btrfs_set_inode_index_count(struct btrfs_inode *inode) 6083 { 6084 struct btrfs_root *root = inode->root; 6085 struct btrfs_key key, found_key; 6086 struct btrfs_path *path; 6087 struct extent_buffer *leaf; 6088 int ret; 6089 6090 key.objectid = btrfs_ino(inode); 6091 key.type = BTRFS_DIR_INDEX_KEY; 6092 key.offset = (u64)-1; 6093 6094 path = btrfs_alloc_path(); 6095 if (!path) 6096 return -ENOMEM; 6097 6098 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 6099 if (ret < 0) 6100 goto out; 6101 /* FIXME: we should be able to handle this */ 6102 if (ret == 0) 6103 goto out; 6104 ret = 0; 6105 6106 /* 6107 * MAGIC NUMBER EXPLANATION: 6108 * since we search a directory based on f_pos we have to start at 2 6109 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody 6110 * else has to start at 2 6111 */ 6112 if (path->slots[0] == 0) { 6113 inode->index_cnt = 2; 6114 goto out; 6115 } 6116 6117 path->slots[0]--; 6118 6119 leaf = path->nodes[0]; 6120 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6121 6122 if (found_key.objectid != btrfs_ino(inode) || 6123 found_key.type != BTRFS_DIR_INDEX_KEY) { 6124 inode->index_cnt = 2; 6125 goto out; 6126 } 6127 6128 inode->index_cnt = found_key.offset + 1; 6129 out: 6130 btrfs_free_path(path); 6131 return ret; 6132 } 6133 6134 /* 6135 * helper to find a free sequence number in a given directory. This current 6136 * code is very simple, later versions will do smarter things in the btree 6137 */ 6138 int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index) 6139 { 6140 int ret = 0; 6141 6142 if (dir->index_cnt == (u64)-1) { 6143 ret = btrfs_inode_delayed_dir_index_count(dir); 6144 if (ret) { 6145 ret = btrfs_set_inode_index_count(dir); 6146 if (ret) 6147 return ret; 6148 } 6149 } 6150 6151 *index = dir->index_cnt; 6152 dir->index_cnt++; 6153 6154 return ret; 6155 } 6156 6157 static int btrfs_insert_inode_locked(struct inode *inode) 6158 { 6159 struct btrfs_iget_args args; 6160 args.location = &BTRFS_I(inode)->location; 6161 args.root = BTRFS_I(inode)->root; 6162 6163 return insert_inode_locked4(inode, 6164 btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root), 6165 btrfs_find_actor, &args); 6166 } 6167 6168 /* 6169 * Inherit flags from the parent inode. 6170 * 6171 * Currently only the compression flags and the cow flags are inherited. 6172 */ 6173 static void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) 6174 { 6175 unsigned int flags; 6176 6177 if (!dir) 6178 return; 6179 6180 flags = BTRFS_I(dir)->flags; 6181 6182 if (flags & BTRFS_INODE_NOCOMPRESS) { 6183 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS; 6184 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; 6185 } else if (flags & BTRFS_INODE_COMPRESS) { 6186 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS; 6187 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS; 6188 } 6189 6190 if (flags & BTRFS_INODE_NODATACOW) { 6191 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; 6192 if (S_ISREG(inode->i_mode)) 6193 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; 6194 } 6195 6196 btrfs_sync_inode_flags_to_i_flags(inode); 6197 } 6198 6199 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, 6200 struct btrfs_root *root, 6201 struct inode *dir, 6202 const char *name, int name_len, 6203 u64 ref_objectid, u64 objectid, 6204 umode_t mode, u64 *index) 6205 { 6206 struct btrfs_fs_info *fs_info = root->fs_info; 6207 struct inode *inode; 6208 struct btrfs_inode_item *inode_item; 6209 struct btrfs_key *location; 6210 struct btrfs_path *path; 6211 struct btrfs_inode_ref *ref; 6212 struct btrfs_key key[2]; 6213 u32 sizes[2]; 6214 int nitems = name ? 2 : 1; 6215 unsigned long ptr; 6216 int ret; 6217 6218 path = btrfs_alloc_path(); 6219 if (!path) 6220 return ERR_PTR(-ENOMEM); 6221 6222 inode = new_inode(fs_info->sb); 6223 if (!inode) { 6224 btrfs_free_path(path); 6225 return ERR_PTR(-ENOMEM); 6226 } 6227 6228 /* 6229 * O_TMPFILE, set link count to 0, so that after this point, 6230 * we fill in an inode item with the correct link count. 6231 */ 6232 if (!name) 6233 set_nlink(inode, 0); 6234 6235 /* 6236 * we have to initialize this early, so we can reclaim the inode 6237 * number if we fail afterwards in this function. 6238 */ 6239 inode->i_ino = objectid; 6240 6241 if (dir && name) { 6242 trace_btrfs_inode_request(dir); 6243 6244 ret = btrfs_set_inode_index(BTRFS_I(dir), index); 6245 if (ret) { 6246 btrfs_free_path(path); 6247 iput(inode); 6248 return ERR_PTR(ret); 6249 } 6250 } else if (dir) { 6251 *index = 0; 6252 } 6253 /* 6254 * index_cnt is ignored for everything but a dir, 6255 * btrfs_set_inode_index_count has an explanation for the magic 6256 * number 6257 */ 6258 BTRFS_I(inode)->index_cnt = 2; 6259 BTRFS_I(inode)->dir_index = *index; 6260 BTRFS_I(inode)->root = root; 6261 BTRFS_I(inode)->generation = trans->transid; 6262 inode->i_generation = BTRFS_I(inode)->generation; 6263 6264 /* 6265 * We could have gotten an inode number from somebody who was fsynced 6266 * and then removed in this same transaction, so let's just set full 6267 * sync since it will be a full sync anyway and this will blow away the 6268 * old info in the log. 6269 */ 6270 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 6271 6272 key[0].objectid = objectid; 6273 key[0].type = BTRFS_INODE_ITEM_KEY; 6274 key[0].offset = 0; 6275 6276 sizes[0] = sizeof(struct btrfs_inode_item); 6277 6278 if (name) { 6279 /* 6280 * Start new inodes with an inode_ref. This is slightly more 6281 * efficient for small numbers of hard links since they will 6282 * be packed into one item. Extended refs will kick in if we 6283 * add more hard links than can fit in the ref item. 6284 */ 6285 key[1].objectid = objectid; 6286 key[1].type = BTRFS_INODE_REF_KEY; 6287 key[1].offset = ref_objectid; 6288 6289 sizes[1] = name_len + sizeof(*ref); 6290 } 6291 6292 location = &BTRFS_I(inode)->location; 6293 location->objectid = objectid; 6294 location->offset = 0; 6295 location->type = BTRFS_INODE_ITEM_KEY; 6296 6297 ret = btrfs_insert_inode_locked(inode); 6298 if (ret < 0) { 6299 iput(inode); 6300 goto fail; 6301 } 6302 6303 path->leave_spinning = 1; 6304 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems); 6305 if (ret != 0) 6306 goto fail_unlock; 6307 6308 inode_init_owner(inode, dir, mode); 6309 inode_set_bytes(inode, 0); 6310 6311 inode->i_mtime = current_time(inode); 6312 inode->i_atime = inode->i_mtime; 6313 inode->i_ctime = inode->i_mtime; 6314 BTRFS_I(inode)->i_otime = inode->i_mtime; 6315 6316 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0], 6317 struct btrfs_inode_item); 6318 memzero_extent_buffer(path->nodes[0], (unsigned long)inode_item, 6319 sizeof(*inode_item)); 6320 fill_inode_item(trans, path->nodes[0], inode_item, inode); 6321 6322 if (name) { 6323 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, 6324 struct btrfs_inode_ref); 6325 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len); 6326 btrfs_set_inode_ref_index(path->nodes[0], ref, *index); 6327 ptr = (unsigned long)(ref + 1); 6328 write_extent_buffer(path->nodes[0], name, ptr, name_len); 6329 } 6330 6331 btrfs_mark_buffer_dirty(path->nodes[0]); 6332 btrfs_free_path(path); 6333 6334 btrfs_inherit_iflags(inode, dir); 6335 6336 if (S_ISREG(mode)) { 6337 if (btrfs_test_opt(fs_info, NODATASUM)) 6338 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; 6339 if (btrfs_test_opt(fs_info, NODATACOW)) 6340 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW | 6341 BTRFS_INODE_NODATASUM; 6342 } 6343 6344 inode_tree_add(inode); 6345 6346 trace_btrfs_inode_new(inode); 6347 btrfs_set_inode_last_trans(trans, inode); 6348 6349 btrfs_update_root_times(trans, root); 6350 6351 ret = btrfs_inode_inherit_props(trans, inode, dir); 6352 if (ret) 6353 btrfs_err(fs_info, 6354 "error inheriting props for ino %llu (root %llu): %d", 6355 btrfs_ino(BTRFS_I(inode)), root->root_key.objectid, ret); 6356 6357 return inode; 6358 6359 fail_unlock: 6360 discard_new_inode(inode); 6361 fail: 6362 if (dir && name) 6363 BTRFS_I(dir)->index_cnt--; 6364 btrfs_free_path(path); 6365 return ERR_PTR(ret); 6366 } 6367 6368 static inline u8 btrfs_inode_type(struct inode *inode) 6369 { 6370 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT]; 6371 } 6372 6373 /* 6374 * utility function to add 'inode' into 'parent_inode' with 6375 * a give name and a given sequence number. 6376 * if 'add_backref' is true, also insert a backref from the 6377 * inode to the parent directory. 6378 */ 6379 int btrfs_add_link(struct btrfs_trans_handle *trans, 6380 struct btrfs_inode *parent_inode, struct btrfs_inode *inode, 6381 const char *name, int name_len, int add_backref, u64 index) 6382 { 6383 int ret = 0; 6384 struct btrfs_key key; 6385 struct btrfs_root *root = parent_inode->root; 6386 u64 ino = btrfs_ino(inode); 6387 u64 parent_ino = btrfs_ino(parent_inode); 6388 6389 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6390 memcpy(&key, &inode->root->root_key, sizeof(key)); 6391 } else { 6392 key.objectid = ino; 6393 key.type = BTRFS_INODE_ITEM_KEY; 6394 key.offset = 0; 6395 } 6396 6397 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6398 ret = btrfs_add_root_ref(trans, key.objectid, 6399 root->root_key.objectid, parent_ino, 6400 index, name, name_len); 6401 } else if (add_backref) { 6402 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino, 6403 parent_ino, index); 6404 } 6405 6406 /* Nothing to clean up yet */ 6407 if (ret) 6408 return ret; 6409 6410 ret = btrfs_insert_dir_item(trans, root, name, name_len, 6411 parent_inode, &key, 6412 btrfs_inode_type(&inode->vfs_inode), index); 6413 if (ret == -EEXIST || ret == -EOVERFLOW) 6414 goto fail_dir_item; 6415 else if (ret) { 6416 btrfs_abort_transaction(trans, ret); 6417 return ret; 6418 } 6419 6420 btrfs_i_size_write(parent_inode, parent_inode->vfs_inode.i_size + 6421 name_len * 2); 6422 inode_inc_iversion(&parent_inode->vfs_inode); 6423 parent_inode->vfs_inode.i_mtime = parent_inode->vfs_inode.i_ctime = 6424 current_time(&parent_inode->vfs_inode); 6425 ret = btrfs_update_inode(trans, root, &parent_inode->vfs_inode); 6426 if (ret) 6427 btrfs_abort_transaction(trans, ret); 6428 return ret; 6429 6430 fail_dir_item: 6431 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { 6432 u64 local_index; 6433 int err; 6434 err = btrfs_del_root_ref(trans, key.objectid, 6435 root->root_key.objectid, parent_ino, 6436 &local_index, name, name_len); 6437 6438 } else if (add_backref) { 6439 u64 local_index; 6440 int err; 6441 6442 err = btrfs_del_inode_ref(trans, root, name, name_len, 6443 ino, parent_ino, &local_index); 6444 } 6445 return ret; 6446 } 6447 6448 static int btrfs_add_nondir(struct btrfs_trans_handle *trans, 6449 struct btrfs_inode *dir, struct dentry *dentry, 6450 struct btrfs_inode *inode, int backref, u64 index) 6451 { 6452 int err = btrfs_add_link(trans, dir, inode, 6453 dentry->d_name.name, dentry->d_name.len, 6454 backref, index); 6455 if (err > 0) 6456 err = -EEXIST; 6457 return err; 6458 } 6459 6460 static int btrfs_mknod(struct inode *dir, struct dentry *dentry, 6461 umode_t mode, dev_t rdev) 6462 { 6463 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 6464 struct btrfs_trans_handle *trans; 6465 struct btrfs_root *root = BTRFS_I(dir)->root; 6466 struct inode *inode = NULL; 6467 int err; 6468 u64 objectid; 6469 u64 index = 0; 6470 6471 /* 6472 * 2 for inode item and ref 6473 * 2 for dir items 6474 * 1 for xattr if selinux is on 6475 */ 6476 trans = btrfs_start_transaction(root, 5); 6477 if (IS_ERR(trans)) 6478 return PTR_ERR(trans); 6479 6480 err = btrfs_find_free_ino(root, &objectid); 6481 if (err) 6482 goto out_unlock; 6483 6484 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6485 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, 6486 mode, &index); 6487 if (IS_ERR(inode)) { 6488 err = PTR_ERR(inode); 6489 inode = NULL; 6490 goto out_unlock; 6491 } 6492 6493 /* 6494 * If the active LSM wants to access the inode during 6495 * d_instantiate it needs these. Smack checks to see 6496 * if the filesystem supports xattrs by looking at the 6497 * ops vector. 6498 */ 6499 inode->i_op = &btrfs_special_inode_operations; 6500 init_special_inode(inode, inode->i_mode, rdev); 6501 6502 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6503 if (err) 6504 goto out_unlock; 6505 6506 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 6507 0, index); 6508 if (err) 6509 goto out_unlock; 6510 6511 btrfs_update_inode(trans, root, inode); 6512 d_instantiate_new(dentry, inode); 6513 6514 out_unlock: 6515 btrfs_end_transaction(trans); 6516 btrfs_btree_balance_dirty(fs_info); 6517 if (err && inode) { 6518 inode_dec_link_count(inode); 6519 discard_new_inode(inode); 6520 } 6521 return err; 6522 } 6523 6524 static int btrfs_create(struct inode *dir, struct dentry *dentry, 6525 umode_t mode, bool excl) 6526 { 6527 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 6528 struct btrfs_trans_handle *trans; 6529 struct btrfs_root *root = BTRFS_I(dir)->root; 6530 struct inode *inode = NULL; 6531 int err; 6532 u64 objectid; 6533 u64 index = 0; 6534 6535 /* 6536 * 2 for inode item and ref 6537 * 2 for dir items 6538 * 1 for xattr if selinux is on 6539 */ 6540 trans = btrfs_start_transaction(root, 5); 6541 if (IS_ERR(trans)) 6542 return PTR_ERR(trans); 6543 6544 err = btrfs_find_free_ino(root, &objectid); 6545 if (err) 6546 goto out_unlock; 6547 6548 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6549 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, 6550 mode, &index); 6551 if (IS_ERR(inode)) { 6552 err = PTR_ERR(inode); 6553 inode = NULL; 6554 goto out_unlock; 6555 } 6556 /* 6557 * If the active LSM wants to access the inode during 6558 * d_instantiate it needs these. Smack checks to see 6559 * if the filesystem supports xattrs by looking at the 6560 * ops vector. 6561 */ 6562 inode->i_fop = &btrfs_file_operations; 6563 inode->i_op = &btrfs_file_inode_operations; 6564 inode->i_mapping->a_ops = &btrfs_aops; 6565 6566 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6567 if (err) 6568 goto out_unlock; 6569 6570 err = btrfs_update_inode(trans, root, inode); 6571 if (err) 6572 goto out_unlock; 6573 6574 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 6575 0, index); 6576 if (err) 6577 goto out_unlock; 6578 6579 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 6580 d_instantiate_new(dentry, inode); 6581 6582 out_unlock: 6583 btrfs_end_transaction(trans); 6584 if (err && inode) { 6585 inode_dec_link_count(inode); 6586 discard_new_inode(inode); 6587 } 6588 btrfs_btree_balance_dirty(fs_info); 6589 return err; 6590 } 6591 6592 static int btrfs_link(struct dentry *old_dentry, struct inode *dir, 6593 struct dentry *dentry) 6594 { 6595 struct btrfs_trans_handle *trans = NULL; 6596 struct btrfs_root *root = BTRFS_I(dir)->root; 6597 struct inode *inode = d_inode(old_dentry); 6598 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 6599 u64 index; 6600 int err; 6601 int drop_inode = 0; 6602 6603 /* do not allow sys_link's with other subvols of the same device */ 6604 if (root->objectid != BTRFS_I(inode)->root->objectid) 6605 return -EXDEV; 6606 6607 if (inode->i_nlink >= BTRFS_LINK_MAX) 6608 return -EMLINK; 6609 6610 err = btrfs_set_inode_index(BTRFS_I(dir), &index); 6611 if (err) 6612 goto fail; 6613 6614 /* 6615 * 2 items for inode and inode ref 6616 * 2 items for dir items 6617 * 1 item for parent inode 6618 * 1 item for orphan item deletion if O_TMPFILE 6619 */ 6620 trans = btrfs_start_transaction(root, inode->i_nlink ? 5 : 6); 6621 if (IS_ERR(trans)) { 6622 err = PTR_ERR(trans); 6623 trans = NULL; 6624 goto fail; 6625 } 6626 6627 /* There are several dir indexes for this inode, clear the cache. */ 6628 BTRFS_I(inode)->dir_index = 0ULL; 6629 inc_nlink(inode); 6630 inode_inc_iversion(inode); 6631 inode->i_ctime = current_time(inode); 6632 ihold(inode); 6633 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags); 6634 6635 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode), 6636 1, index); 6637 6638 if (err) { 6639 drop_inode = 1; 6640 } else { 6641 struct dentry *parent = dentry->d_parent; 6642 err = btrfs_update_inode(trans, root, inode); 6643 if (err) 6644 goto fail; 6645 if (inode->i_nlink == 1) { 6646 /* 6647 * If new hard link count is 1, it's a file created 6648 * with open(2) O_TMPFILE flag. 6649 */ 6650 err = btrfs_orphan_del(trans, BTRFS_I(inode)); 6651 if (err) 6652 goto fail; 6653 } 6654 d_instantiate(dentry, inode); 6655 btrfs_log_new_name(trans, BTRFS_I(inode), NULL, parent); 6656 } 6657 6658 fail: 6659 if (trans) 6660 btrfs_end_transaction(trans); 6661 if (drop_inode) { 6662 inode_dec_link_count(inode); 6663 iput(inode); 6664 } 6665 btrfs_btree_balance_dirty(fs_info); 6666 return err; 6667 } 6668 6669 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 6670 { 6671 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 6672 struct inode *inode = NULL; 6673 struct btrfs_trans_handle *trans; 6674 struct btrfs_root *root = BTRFS_I(dir)->root; 6675 int err = 0; 6676 int drop_on_err = 0; 6677 u64 objectid = 0; 6678 u64 index = 0; 6679 6680 /* 6681 * 2 items for inode and ref 6682 * 2 items for dir items 6683 * 1 for xattr if selinux is on 6684 */ 6685 trans = btrfs_start_transaction(root, 5); 6686 if (IS_ERR(trans)) 6687 return PTR_ERR(trans); 6688 6689 err = btrfs_find_free_ino(root, &objectid); 6690 if (err) 6691 goto out_fail; 6692 6693 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 6694 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid, 6695 S_IFDIR | mode, &index); 6696 if (IS_ERR(inode)) { 6697 err = PTR_ERR(inode); 6698 inode = NULL; 6699 goto out_fail; 6700 } 6701 6702 drop_on_err = 1; 6703 /* these must be set before we unlock the inode */ 6704 inode->i_op = &btrfs_dir_inode_operations; 6705 inode->i_fop = &btrfs_dir_file_operations; 6706 6707 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 6708 if (err) 6709 goto out_fail; 6710 6711 btrfs_i_size_write(BTRFS_I(inode), 0); 6712 err = btrfs_update_inode(trans, root, inode); 6713 if (err) 6714 goto out_fail; 6715 6716 err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), 6717 dentry->d_name.name, 6718 dentry->d_name.len, 0, index); 6719 if (err) 6720 goto out_fail; 6721 6722 d_instantiate_new(dentry, inode); 6723 drop_on_err = 0; 6724 6725 out_fail: 6726 btrfs_end_transaction(trans); 6727 if (err && inode) { 6728 inode_dec_link_count(inode); 6729 discard_new_inode(inode); 6730 } 6731 btrfs_btree_balance_dirty(fs_info); 6732 return err; 6733 } 6734 6735 static noinline int uncompress_inline(struct btrfs_path *path, 6736 struct page *page, 6737 size_t pg_offset, u64 extent_offset, 6738 struct btrfs_file_extent_item *item) 6739 { 6740 int ret; 6741 struct extent_buffer *leaf = path->nodes[0]; 6742 char *tmp; 6743 size_t max_size; 6744 unsigned long inline_size; 6745 unsigned long ptr; 6746 int compress_type; 6747 6748 WARN_ON(pg_offset != 0); 6749 compress_type = btrfs_file_extent_compression(leaf, item); 6750 max_size = btrfs_file_extent_ram_bytes(leaf, item); 6751 inline_size = btrfs_file_extent_inline_item_len(leaf, 6752 btrfs_item_nr(path->slots[0])); 6753 tmp = kmalloc(inline_size, GFP_NOFS); 6754 if (!tmp) 6755 return -ENOMEM; 6756 ptr = btrfs_file_extent_inline_start(item); 6757 6758 read_extent_buffer(leaf, tmp, ptr, inline_size); 6759 6760 max_size = min_t(unsigned long, PAGE_SIZE, max_size); 6761 ret = btrfs_decompress(compress_type, tmp, page, 6762 extent_offset, inline_size, max_size); 6763 6764 /* 6765 * decompression code contains a memset to fill in any space between the end 6766 * of the uncompressed data and the end of max_size in case the decompressed 6767 * data ends up shorter than ram_bytes. That doesn't cover the hole between 6768 * the end of an inline extent and the beginning of the next block, so we 6769 * cover that region here. 6770 */ 6771 6772 if (max_size + pg_offset < PAGE_SIZE) { 6773 char *map = kmap(page); 6774 memset(map + pg_offset + max_size, 0, PAGE_SIZE - max_size - pg_offset); 6775 kunmap(page); 6776 } 6777 kfree(tmp); 6778 return ret; 6779 } 6780 6781 /* 6782 * a bit scary, this does extent mapping from logical file offset to the disk. 6783 * the ugly parts come from merging extents from the disk with the in-ram 6784 * representation. This gets more complex because of the data=ordered code, 6785 * where the in-ram extents might be locked pending data=ordered completion. 6786 * 6787 * This also copies inline extents directly into the page. 6788 */ 6789 struct extent_map *btrfs_get_extent(struct btrfs_inode *inode, 6790 struct page *page, 6791 size_t pg_offset, u64 start, u64 len, 6792 int create) 6793 { 6794 struct btrfs_fs_info *fs_info = inode->root->fs_info; 6795 int ret; 6796 int err = 0; 6797 u64 extent_start = 0; 6798 u64 extent_end = 0; 6799 u64 objectid = btrfs_ino(inode); 6800 u32 found_type; 6801 struct btrfs_path *path = NULL; 6802 struct btrfs_root *root = inode->root; 6803 struct btrfs_file_extent_item *item; 6804 struct extent_buffer *leaf; 6805 struct btrfs_key found_key; 6806 struct extent_map *em = NULL; 6807 struct extent_map_tree *em_tree = &inode->extent_tree; 6808 struct extent_io_tree *io_tree = &inode->io_tree; 6809 const bool new_inline = !page || create; 6810 6811 read_lock(&em_tree->lock); 6812 em = lookup_extent_mapping(em_tree, start, len); 6813 if (em) 6814 em->bdev = fs_info->fs_devices->latest_bdev; 6815 read_unlock(&em_tree->lock); 6816 6817 if (em) { 6818 if (em->start > start || em->start + em->len <= start) 6819 free_extent_map(em); 6820 else if (em->block_start == EXTENT_MAP_INLINE && page) 6821 free_extent_map(em); 6822 else 6823 goto out; 6824 } 6825 em = alloc_extent_map(); 6826 if (!em) { 6827 err = -ENOMEM; 6828 goto out; 6829 } 6830 em->bdev = fs_info->fs_devices->latest_bdev; 6831 em->start = EXTENT_MAP_HOLE; 6832 em->orig_start = EXTENT_MAP_HOLE; 6833 em->len = (u64)-1; 6834 em->block_len = (u64)-1; 6835 6836 if (!path) { 6837 path = btrfs_alloc_path(); 6838 if (!path) { 6839 err = -ENOMEM; 6840 goto out; 6841 } 6842 /* 6843 * Chances are we'll be called again, so go ahead and do 6844 * readahead 6845 */ 6846 path->reada = READA_FORWARD; 6847 } 6848 6849 ret = btrfs_lookup_file_extent(NULL, root, path, objectid, start, 0); 6850 if (ret < 0) { 6851 err = ret; 6852 goto out; 6853 } 6854 6855 if (ret != 0) { 6856 if (path->slots[0] == 0) 6857 goto not_found; 6858 path->slots[0]--; 6859 } 6860 6861 leaf = path->nodes[0]; 6862 item = btrfs_item_ptr(leaf, path->slots[0], 6863 struct btrfs_file_extent_item); 6864 /* are we inside the extent that was found? */ 6865 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6866 found_type = found_key.type; 6867 if (found_key.objectid != objectid || 6868 found_type != BTRFS_EXTENT_DATA_KEY) { 6869 /* 6870 * If we backup past the first extent we want to move forward 6871 * and see if there is an extent in front of us, otherwise we'll 6872 * say there is a hole for our whole search range which can 6873 * cause problems. 6874 */ 6875 extent_end = start; 6876 goto next; 6877 } 6878 6879 found_type = btrfs_file_extent_type(leaf, item); 6880 extent_start = found_key.offset; 6881 if (found_type == BTRFS_FILE_EXTENT_REG || 6882 found_type == BTRFS_FILE_EXTENT_PREALLOC) { 6883 extent_end = extent_start + 6884 btrfs_file_extent_num_bytes(leaf, item); 6885 6886 trace_btrfs_get_extent_show_fi_regular(inode, leaf, item, 6887 extent_start); 6888 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { 6889 size_t size; 6890 6891 size = btrfs_file_extent_ram_bytes(leaf, item); 6892 extent_end = ALIGN(extent_start + size, 6893 fs_info->sectorsize); 6894 6895 trace_btrfs_get_extent_show_fi_inline(inode, leaf, item, 6896 path->slots[0], 6897 extent_start); 6898 } 6899 next: 6900 if (start >= extent_end) { 6901 path->slots[0]++; 6902 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 6903 ret = btrfs_next_leaf(root, path); 6904 if (ret < 0) { 6905 err = ret; 6906 goto out; 6907 } 6908 if (ret > 0) 6909 goto not_found; 6910 leaf = path->nodes[0]; 6911 } 6912 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 6913 if (found_key.objectid != objectid || 6914 found_key.type != BTRFS_EXTENT_DATA_KEY) 6915 goto not_found; 6916 if (start + len <= found_key.offset) 6917 goto not_found; 6918 if (start > found_key.offset) 6919 goto next; 6920 em->start = start; 6921 em->orig_start = start; 6922 em->len = found_key.offset - start; 6923 goto not_found_em; 6924 } 6925 6926 btrfs_extent_item_to_extent_map(inode, path, item, 6927 new_inline, em); 6928 6929 if (found_type == BTRFS_FILE_EXTENT_REG || 6930 found_type == BTRFS_FILE_EXTENT_PREALLOC) { 6931 goto insert; 6932 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { 6933 unsigned long ptr; 6934 char *map; 6935 size_t size; 6936 size_t extent_offset; 6937 size_t copy_size; 6938 6939 if (new_inline) 6940 goto out; 6941 6942 size = btrfs_file_extent_ram_bytes(leaf, item); 6943 extent_offset = page_offset(page) + pg_offset - extent_start; 6944 copy_size = min_t(u64, PAGE_SIZE - pg_offset, 6945 size - extent_offset); 6946 em->start = extent_start + extent_offset; 6947 em->len = ALIGN(copy_size, fs_info->sectorsize); 6948 em->orig_block_len = em->len; 6949 em->orig_start = em->start; 6950 ptr = btrfs_file_extent_inline_start(item) + extent_offset; 6951 if (!PageUptodate(page)) { 6952 if (btrfs_file_extent_compression(leaf, item) != 6953 BTRFS_COMPRESS_NONE) { 6954 ret = uncompress_inline(path, page, pg_offset, 6955 extent_offset, item); 6956 if (ret) { 6957 err = ret; 6958 goto out; 6959 } 6960 } else { 6961 map = kmap(page); 6962 read_extent_buffer(leaf, map + pg_offset, ptr, 6963 copy_size); 6964 if (pg_offset + copy_size < PAGE_SIZE) { 6965 memset(map + pg_offset + copy_size, 0, 6966 PAGE_SIZE - pg_offset - 6967 copy_size); 6968 } 6969 kunmap(page); 6970 } 6971 flush_dcache_page(page); 6972 } 6973 set_extent_uptodate(io_tree, em->start, 6974 extent_map_end(em) - 1, NULL, GFP_NOFS); 6975 goto insert; 6976 } 6977 not_found: 6978 em->start = start; 6979 em->orig_start = start; 6980 em->len = len; 6981 not_found_em: 6982 em->block_start = EXTENT_MAP_HOLE; 6983 insert: 6984 btrfs_release_path(path); 6985 if (em->start > start || extent_map_end(em) <= start) { 6986 btrfs_err(fs_info, 6987 "bad extent! em: [%llu %llu] passed [%llu %llu]", 6988 em->start, em->len, start, len); 6989 err = -EIO; 6990 goto out; 6991 } 6992 6993 err = 0; 6994 write_lock(&em_tree->lock); 6995 err = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len); 6996 write_unlock(&em_tree->lock); 6997 out: 6998 6999 trace_btrfs_get_extent(root, inode, em); 7000 7001 btrfs_free_path(path); 7002 if (err) { 7003 free_extent_map(em); 7004 return ERR_PTR(err); 7005 } 7006 BUG_ON(!em); /* Error is always set */ 7007 return em; 7008 } 7009 7010 struct extent_map *btrfs_get_extent_fiemap(struct btrfs_inode *inode, 7011 struct page *page, 7012 size_t pg_offset, u64 start, u64 len, 7013 int create) 7014 { 7015 struct extent_map *em; 7016 struct extent_map *hole_em = NULL; 7017 u64 range_start = start; 7018 u64 end; 7019 u64 found; 7020 u64 found_end; 7021 int err = 0; 7022 7023 em = btrfs_get_extent(inode, page, pg_offset, start, len, create); 7024 if (IS_ERR(em)) 7025 return em; 7026 /* 7027 * If our em maps to: 7028 * - a hole or 7029 * - a pre-alloc extent, 7030 * there might actually be delalloc bytes behind it. 7031 */ 7032 if (em->block_start != EXTENT_MAP_HOLE && 7033 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7034 return em; 7035 else 7036 hole_em = em; 7037 7038 /* check to see if we've wrapped (len == -1 or similar) */ 7039 end = start + len; 7040 if (end < start) 7041 end = (u64)-1; 7042 else 7043 end -= 1; 7044 7045 em = NULL; 7046 7047 /* ok, we didn't find anything, lets look for delalloc */ 7048 found = count_range_bits(&inode->io_tree, &range_start, 7049 end, len, EXTENT_DELALLOC, 1); 7050 found_end = range_start + found; 7051 if (found_end < range_start) 7052 found_end = (u64)-1; 7053 7054 /* 7055 * we didn't find anything useful, return 7056 * the original results from get_extent() 7057 */ 7058 if (range_start > end || found_end <= start) { 7059 em = hole_em; 7060 hole_em = NULL; 7061 goto out; 7062 } 7063 7064 /* adjust the range_start to make sure it doesn't 7065 * go backwards from the start they passed in 7066 */ 7067 range_start = max(start, range_start); 7068 found = found_end - range_start; 7069 7070 if (found > 0) { 7071 u64 hole_start = start; 7072 u64 hole_len = len; 7073 7074 em = alloc_extent_map(); 7075 if (!em) { 7076 err = -ENOMEM; 7077 goto out; 7078 } 7079 /* 7080 * when btrfs_get_extent can't find anything it 7081 * returns one huge hole 7082 * 7083 * make sure what it found really fits our range, and 7084 * adjust to make sure it is based on the start from 7085 * the caller 7086 */ 7087 if (hole_em) { 7088 u64 calc_end = extent_map_end(hole_em); 7089 7090 if (calc_end <= start || (hole_em->start > end)) { 7091 free_extent_map(hole_em); 7092 hole_em = NULL; 7093 } else { 7094 hole_start = max(hole_em->start, start); 7095 hole_len = calc_end - hole_start; 7096 } 7097 } 7098 em->bdev = NULL; 7099 if (hole_em && range_start > hole_start) { 7100 /* our hole starts before our delalloc, so we 7101 * have to return just the parts of the hole 7102 * that go until the delalloc starts 7103 */ 7104 em->len = min(hole_len, 7105 range_start - hole_start); 7106 em->start = hole_start; 7107 em->orig_start = hole_start; 7108 /* 7109 * don't adjust block start at all, 7110 * it is fixed at EXTENT_MAP_HOLE 7111 */ 7112 em->block_start = hole_em->block_start; 7113 em->block_len = hole_len; 7114 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags)) 7115 set_bit(EXTENT_FLAG_PREALLOC, &em->flags); 7116 } else { 7117 em->start = range_start; 7118 em->len = found; 7119 em->orig_start = range_start; 7120 em->block_start = EXTENT_MAP_DELALLOC; 7121 em->block_len = found; 7122 } 7123 } else { 7124 return hole_em; 7125 } 7126 out: 7127 7128 free_extent_map(hole_em); 7129 if (err) { 7130 free_extent_map(em); 7131 return ERR_PTR(err); 7132 } 7133 return em; 7134 } 7135 7136 static struct extent_map *btrfs_create_dio_extent(struct inode *inode, 7137 const u64 start, 7138 const u64 len, 7139 const u64 orig_start, 7140 const u64 block_start, 7141 const u64 block_len, 7142 const u64 orig_block_len, 7143 const u64 ram_bytes, 7144 const int type) 7145 { 7146 struct extent_map *em = NULL; 7147 int ret; 7148 7149 if (type != BTRFS_ORDERED_NOCOW) { 7150 em = create_io_em(inode, start, len, orig_start, 7151 block_start, block_len, orig_block_len, 7152 ram_bytes, 7153 BTRFS_COMPRESS_NONE, /* compress_type */ 7154 type); 7155 if (IS_ERR(em)) 7156 goto out; 7157 } 7158 ret = btrfs_add_ordered_extent_dio(inode, start, block_start, 7159 len, block_len, type); 7160 if (ret) { 7161 if (em) { 7162 free_extent_map(em); 7163 btrfs_drop_extent_cache(BTRFS_I(inode), start, 7164 start + len - 1, 0); 7165 } 7166 em = ERR_PTR(ret); 7167 } 7168 out: 7169 7170 return em; 7171 } 7172 7173 static struct extent_map *btrfs_new_extent_direct(struct inode *inode, 7174 u64 start, u64 len) 7175 { 7176 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7177 struct btrfs_root *root = BTRFS_I(inode)->root; 7178 struct extent_map *em; 7179 struct btrfs_key ins; 7180 u64 alloc_hint; 7181 int ret; 7182 7183 alloc_hint = get_extent_allocation_hint(inode, start, len); 7184 ret = btrfs_reserve_extent(root, len, len, fs_info->sectorsize, 7185 0, alloc_hint, &ins, 1, 1); 7186 if (ret) 7187 return ERR_PTR(ret); 7188 7189 em = btrfs_create_dio_extent(inode, start, ins.offset, start, 7190 ins.objectid, ins.offset, ins.offset, 7191 ins.offset, BTRFS_ORDERED_REGULAR); 7192 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 7193 if (IS_ERR(em)) 7194 btrfs_free_reserved_extent(fs_info, ins.objectid, 7195 ins.offset, 1); 7196 7197 return em; 7198 } 7199 7200 /* 7201 * returns 1 when the nocow is safe, < 1 on error, 0 if the 7202 * block must be cow'd 7203 */ 7204 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len, 7205 u64 *orig_start, u64 *orig_block_len, 7206 u64 *ram_bytes) 7207 { 7208 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7209 struct btrfs_path *path; 7210 int ret; 7211 struct extent_buffer *leaf; 7212 struct btrfs_root *root = BTRFS_I(inode)->root; 7213 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 7214 struct btrfs_file_extent_item *fi; 7215 struct btrfs_key key; 7216 u64 disk_bytenr; 7217 u64 backref_offset; 7218 u64 extent_end; 7219 u64 num_bytes; 7220 int slot; 7221 int found_type; 7222 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW); 7223 7224 path = btrfs_alloc_path(); 7225 if (!path) 7226 return -ENOMEM; 7227 7228 ret = btrfs_lookup_file_extent(NULL, root, path, 7229 btrfs_ino(BTRFS_I(inode)), offset, 0); 7230 if (ret < 0) 7231 goto out; 7232 7233 slot = path->slots[0]; 7234 if (ret == 1) { 7235 if (slot == 0) { 7236 /* can't find the item, must cow */ 7237 ret = 0; 7238 goto out; 7239 } 7240 slot--; 7241 } 7242 ret = 0; 7243 leaf = path->nodes[0]; 7244 btrfs_item_key_to_cpu(leaf, &key, slot); 7245 if (key.objectid != btrfs_ino(BTRFS_I(inode)) || 7246 key.type != BTRFS_EXTENT_DATA_KEY) { 7247 /* not our file or wrong item type, must cow */ 7248 goto out; 7249 } 7250 7251 if (key.offset > offset) { 7252 /* Wrong offset, must cow */ 7253 goto out; 7254 } 7255 7256 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); 7257 found_type = btrfs_file_extent_type(leaf, fi); 7258 if (found_type != BTRFS_FILE_EXTENT_REG && 7259 found_type != BTRFS_FILE_EXTENT_PREALLOC) { 7260 /* not a regular extent, must cow */ 7261 goto out; 7262 } 7263 7264 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG) 7265 goto out; 7266 7267 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); 7268 if (extent_end <= offset) 7269 goto out; 7270 7271 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 7272 if (disk_bytenr == 0) 7273 goto out; 7274 7275 if (btrfs_file_extent_compression(leaf, fi) || 7276 btrfs_file_extent_encryption(leaf, fi) || 7277 btrfs_file_extent_other_encoding(leaf, fi)) 7278 goto out; 7279 7280 /* 7281 * Do the same check as in btrfs_cross_ref_exist but without the 7282 * unnecessary search. 7283 */ 7284 if (btrfs_file_extent_generation(leaf, fi) <= 7285 btrfs_root_last_snapshot(&root->root_item)) 7286 goto out; 7287 7288 backref_offset = btrfs_file_extent_offset(leaf, fi); 7289 7290 if (orig_start) { 7291 *orig_start = key.offset - backref_offset; 7292 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi); 7293 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); 7294 } 7295 7296 if (btrfs_extent_readonly(fs_info, disk_bytenr)) 7297 goto out; 7298 7299 num_bytes = min(offset + *len, extent_end) - offset; 7300 if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) { 7301 u64 range_end; 7302 7303 range_end = round_up(offset + num_bytes, 7304 root->fs_info->sectorsize) - 1; 7305 ret = test_range_bit(io_tree, offset, range_end, 7306 EXTENT_DELALLOC, 0, NULL); 7307 if (ret) { 7308 ret = -EAGAIN; 7309 goto out; 7310 } 7311 } 7312 7313 btrfs_release_path(path); 7314 7315 /* 7316 * look for other files referencing this extent, if we 7317 * find any we must cow 7318 */ 7319 7320 ret = btrfs_cross_ref_exist(root, btrfs_ino(BTRFS_I(inode)), 7321 key.offset - backref_offset, disk_bytenr); 7322 if (ret) { 7323 ret = 0; 7324 goto out; 7325 } 7326 7327 /* 7328 * adjust disk_bytenr and num_bytes to cover just the bytes 7329 * in this extent we are about to write. If there 7330 * are any csums in that range we have to cow in order 7331 * to keep the csums correct 7332 */ 7333 disk_bytenr += backref_offset; 7334 disk_bytenr += offset - key.offset; 7335 if (csum_exist_in_range(fs_info, disk_bytenr, num_bytes)) 7336 goto out; 7337 /* 7338 * all of the above have passed, it is safe to overwrite this extent 7339 * without cow 7340 */ 7341 *len = num_bytes; 7342 ret = 1; 7343 out: 7344 btrfs_free_path(path); 7345 return ret; 7346 } 7347 7348 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, 7349 struct extent_state **cached_state, int writing) 7350 { 7351 struct btrfs_ordered_extent *ordered; 7352 int ret = 0; 7353 7354 while (1) { 7355 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7356 cached_state); 7357 /* 7358 * We're concerned with the entire range that we're going to be 7359 * doing DIO to, so we need to make sure there's no ordered 7360 * extents in this range. 7361 */ 7362 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), lockstart, 7363 lockend - lockstart + 1); 7364 7365 /* 7366 * We need to make sure there are no buffered pages in this 7367 * range either, we could have raced between the invalidate in 7368 * generic_file_direct_write and locking the extent. The 7369 * invalidate needs to happen so that reads after a write do not 7370 * get stale data. 7371 */ 7372 if (!ordered && 7373 (!writing || !filemap_range_has_page(inode->i_mapping, 7374 lockstart, lockend))) 7375 break; 7376 7377 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7378 cached_state); 7379 7380 if (ordered) { 7381 /* 7382 * If we are doing a DIO read and the ordered extent we 7383 * found is for a buffered write, we can not wait for it 7384 * to complete and retry, because if we do so we can 7385 * deadlock with concurrent buffered writes on page 7386 * locks. This happens only if our DIO read covers more 7387 * than one extent map, if at this point has already 7388 * created an ordered extent for a previous extent map 7389 * and locked its range in the inode's io tree, and a 7390 * concurrent write against that previous extent map's 7391 * range and this range started (we unlock the ranges 7392 * in the io tree only when the bios complete and 7393 * buffered writes always lock pages before attempting 7394 * to lock range in the io tree). 7395 */ 7396 if (writing || 7397 test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) 7398 btrfs_start_ordered_extent(inode, ordered, 1); 7399 else 7400 ret = -ENOTBLK; 7401 btrfs_put_ordered_extent(ordered); 7402 } else { 7403 /* 7404 * We could trigger writeback for this range (and wait 7405 * for it to complete) and then invalidate the pages for 7406 * this range (through invalidate_inode_pages2_range()), 7407 * but that can lead us to a deadlock with a concurrent 7408 * call to readpages() (a buffered read or a defrag call 7409 * triggered a readahead) on a page lock due to an 7410 * ordered dio extent we created before but did not have 7411 * yet a corresponding bio submitted (whence it can not 7412 * complete), which makes readpages() wait for that 7413 * ordered extent to complete while holding a lock on 7414 * that page. 7415 */ 7416 ret = -ENOTBLK; 7417 } 7418 7419 if (ret) 7420 break; 7421 7422 cond_resched(); 7423 } 7424 7425 return ret; 7426 } 7427 7428 /* The callers of this must take lock_extent() */ 7429 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len, 7430 u64 orig_start, u64 block_start, 7431 u64 block_len, u64 orig_block_len, 7432 u64 ram_bytes, int compress_type, 7433 int type) 7434 { 7435 struct extent_map_tree *em_tree; 7436 struct extent_map *em; 7437 struct btrfs_root *root = BTRFS_I(inode)->root; 7438 int ret; 7439 7440 ASSERT(type == BTRFS_ORDERED_PREALLOC || 7441 type == BTRFS_ORDERED_COMPRESSED || 7442 type == BTRFS_ORDERED_NOCOW || 7443 type == BTRFS_ORDERED_REGULAR); 7444 7445 em_tree = &BTRFS_I(inode)->extent_tree; 7446 em = alloc_extent_map(); 7447 if (!em) 7448 return ERR_PTR(-ENOMEM); 7449 7450 em->start = start; 7451 em->orig_start = orig_start; 7452 em->len = len; 7453 em->block_len = block_len; 7454 em->block_start = block_start; 7455 em->bdev = root->fs_info->fs_devices->latest_bdev; 7456 em->orig_block_len = orig_block_len; 7457 em->ram_bytes = ram_bytes; 7458 em->generation = -1; 7459 set_bit(EXTENT_FLAG_PINNED, &em->flags); 7460 if (type == BTRFS_ORDERED_PREALLOC) { 7461 set_bit(EXTENT_FLAG_FILLING, &em->flags); 7462 } else if (type == BTRFS_ORDERED_COMPRESSED) { 7463 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); 7464 em->compress_type = compress_type; 7465 } 7466 7467 do { 7468 btrfs_drop_extent_cache(BTRFS_I(inode), em->start, 7469 em->start + em->len - 1, 0); 7470 write_lock(&em_tree->lock); 7471 ret = add_extent_mapping(em_tree, em, 1); 7472 write_unlock(&em_tree->lock); 7473 /* 7474 * The caller has taken lock_extent(), who could race with us 7475 * to add em? 7476 */ 7477 } while (ret == -EEXIST); 7478 7479 if (ret) { 7480 free_extent_map(em); 7481 return ERR_PTR(ret); 7482 } 7483 7484 /* em got 2 refs now, callers needs to do free_extent_map once. */ 7485 return em; 7486 } 7487 7488 7489 static int btrfs_get_blocks_direct_read(struct extent_map *em, 7490 struct buffer_head *bh_result, 7491 struct inode *inode, 7492 u64 start, u64 len) 7493 { 7494 if (em->block_start == EXTENT_MAP_HOLE || 7495 test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7496 return -ENOENT; 7497 7498 len = min(len, em->len - (start - em->start)); 7499 7500 bh_result->b_blocknr = (em->block_start + (start - em->start)) >> 7501 inode->i_blkbits; 7502 bh_result->b_size = len; 7503 bh_result->b_bdev = em->bdev; 7504 set_buffer_mapped(bh_result); 7505 7506 return 0; 7507 } 7508 7509 static int btrfs_get_blocks_direct_write(struct extent_map **map, 7510 struct buffer_head *bh_result, 7511 struct inode *inode, 7512 struct btrfs_dio_data *dio_data, 7513 u64 start, u64 len) 7514 { 7515 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7516 struct extent_map *em = *map; 7517 int ret = 0; 7518 7519 /* 7520 * We don't allocate a new extent in the following cases 7521 * 7522 * 1) The inode is marked as NODATACOW. In this case we'll just use the 7523 * existing extent. 7524 * 2) The extent is marked as PREALLOC. We're good to go here and can 7525 * just use the extent. 7526 * 7527 */ 7528 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) || 7529 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && 7530 em->block_start != EXTENT_MAP_HOLE)) { 7531 int type; 7532 u64 block_start, orig_start, orig_block_len, ram_bytes; 7533 7534 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7535 type = BTRFS_ORDERED_PREALLOC; 7536 else 7537 type = BTRFS_ORDERED_NOCOW; 7538 len = min(len, em->len - (start - em->start)); 7539 block_start = em->block_start + (start - em->start); 7540 7541 if (can_nocow_extent(inode, start, &len, &orig_start, 7542 &orig_block_len, &ram_bytes) == 1 && 7543 btrfs_inc_nocow_writers(fs_info, block_start)) { 7544 struct extent_map *em2; 7545 7546 em2 = btrfs_create_dio_extent(inode, start, len, 7547 orig_start, block_start, 7548 len, orig_block_len, 7549 ram_bytes, type); 7550 btrfs_dec_nocow_writers(fs_info, block_start); 7551 if (type == BTRFS_ORDERED_PREALLOC) { 7552 free_extent_map(em); 7553 *map = em = em2; 7554 } 7555 7556 if (em2 && IS_ERR(em2)) { 7557 ret = PTR_ERR(em2); 7558 goto out; 7559 } 7560 /* 7561 * For inode marked NODATACOW or extent marked PREALLOC, 7562 * use the existing or preallocated extent, so does not 7563 * need to adjust btrfs_space_info's bytes_may_use. 7564 */ 7565 btrfs_free_reserved_data_space_noquota(inode, start, 7566 len); 7567 goto skip_cow; 7568 } 7569 } 7570 7571 /* this will cow the extent */ 7572 len = bh_result->b_size; 7573 free_extent_map(em); 7574 *map = em = btrfs_new_extent_direct(inode, start, len); 7575 if (IS_ERR(em)) { 7576 ret = PTR_ERR(em); 7577 goto out; 7578 } 7579 7580 len = min(len, em->len - (start - em->start)); 7581 7582 skip_cow: 7583 bh_result->b_blocknr = (em->block_start + (start - em->start)) >> 7584 inode->i_blkbits; 7585 bh_result->b_size = len; 7586 bh_result->b_bdev = em->bdev; 7587 set_buffer_mapped(bh_result); 7588 7589 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) 7590 set_buffer_new(bh_result); 7591 7592 /* 7593 * Need to update the i_size under the extent lock so buffered 7594 * readers will get the updated i_size when we unlock. 7595 */ 7596 if (!dio_data->overwrite && start + len > i_size_read(inode)) 7597 i_size_write(inode, start + len); 7598 7599 WARN_ON(dio_data->reserve < len); 7600 dio_data->reserve -= len; 7601 dio_data->unsubmitted_oe_range_end = start + len; 7602 current->journal_info = dio_data; 7603 out: 7604 return ret; 7605 } 7606 7607 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock, 7608 struct buffer_head *bh_result, int create) 7609 { 7610 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7611 struct extent_map *em; 7612 struct extent_state *cached_state = NULL; 7613 struct btrfs_dio_data *dio_data = NULL; 7614 u64 start = iblock << inode->i_blkbits; 7615 u64 lockstart, lockend; 7616 u64 len = bh_result->b_size; 7617 int unlock_bits = EXTENT_LOCKED; 7618 int ret = 0; 7619 7620 if (create) 7621 unlock_bits |= EXTENT_DIRTY; 7622 else 7623 len = min_t(u64, len, fs_info->sectorsize); 7624 7625 lockstart = start; 7626 lockend = start + len - 1; 7627 7628 if (current->journal_info) { 7629 /* 7630 * Need to pull our outstanding extents and set journal_info to NULL so 7631 * that anything that needs to check if there's a transaction doesn't get 7632 * confused. 7633 */ 7634 dio_data = current->journal_info; 7635 current->journal_info = NULL; 7636 } 7637 7638 /* 7639 * If this errors out it's because we couldn't invalidate pagecache for 7640 * this range and we need to fallback to buffered. 7641 */ 7642 if (lock_extent_direct(inode, lockstart, lockend, &cached_state, 7643 create)) { 7644 ret = -ENOTBLK; 7645 goto err; 7646 } 7647 7648 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0); 7649 if (IS_ERR(em)) { 7650 ret = PTR_ERR(em); 7651 goto unlock_err; 7652 } 7653 7654 /* 7655 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered 7656 * io. INLINE is special, and we could probably kludge it in here, but 7657 * it's still buffered so for safety lets just fall back to the generic 7658 * buffered path. 7659 * 7660 * For COMPRESSED we _have_ to read the entire extent in so we can 7661 * decompress it, so there will be buffering required no matter what we 7662 * do, so go ahead and fallback to buffered. 7663 * 7664 * We return -ENOTBLK because that's what makes DIO go ahead and go back 7665 * to buffered IO. Don't blame me, this is the price we pay for using 7666 * the generic code. 7667 */ 7668 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) || 7669 em->block_start == EXTENT_MAP_INLINE) { 7670 free_extent_map(em); 7671 ret = -ENOTBLK; 7672 goto unlock_err; 7673 } 7674 7675 if (create) { 7676 ret = btrfs_get_blocks_direct_write(&em, bh_result, inode, 7677 dio_data, start, len); 7678 if (ret < 0) 7679 goto unlock_err; 7680 7681 /* clear and unlock the entire range */ 7682 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7683 unlock_bits, 1, 0, &cached_state); 7684 } else { 7685 ret = btrfs_get_blocks_direct_read(em, bh_result, inode, 7686 start, len); 7687 /* Can be negative only if we read from a hole */ 7688 if (ret < 0) { 7689 ret = 0; 7690 free_extent_map(em); 7691 goto unlock_err; 7692 } 7693 /* 7694 * We need to unlock only the end area that we aren't using. 7695 * The rest is going to be unlocked by the endio routine. 7696 */ 7697 lockstart = start + bh_result->b_size; 7698 if (lockstart < lockend) { 7699 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, 7700 lockend, unlock_bits, 1, 0, 7701 &cached_state); 7702 } else { 7703 free_extent_state(cached_state); 7704 } 7705 } 7706 7707 free_extent_map(em); 7708 7709 return 0; 7710 7711 unlock_err: 7712 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, 7713 unlock_bits, 1, 0, &cached_state); 7714 err: 7715 if (dio_data) 7716 current->journal_info = dio_data; 7717 return ret; 7718 } 7719 7720 static inline blk_status_t submit_dio_repair_bio(struct inode *inode, 7721 struct bio *bio, 7722 int mirror_num) 7723 { 7724 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7725 blk_status_t ret; 7726 7727 BUG_ON(bio_op(bio) == REQ_OP_WRITE); 7728 7729 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DIO_REPAIR); 7730 if (ret) 7731 return ret; 7732 7733 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0); 7734 7735 return ret; 7736 } 7737 7738 static int btrfs_check_dio_repairable(struct inode *inode, 7739 struct bio *failed_bio, 7740 struct io_failure_record *failrec, 7741 int failed_mirror) 7742 { 7743 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 7744 int num_copies; 7745 7746 num_copies = btrfs_num_copies(fs_info, failrec->logical, failrec->len); 7747 if (num_copies == 1) { 7748 /* 7749 * we only have a single copy of the data, so don't bother with 7750 * all the retry and error correction code that follows. no 7751 * matter what the error is, it is very likely to persist. 7752 */ 7753 btrfs_debug(fs_info, 7754 "Check DIO Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d", 7755 num_copies, failrec->this_mirror, failed_mirror); 7756 return 0; 7757 } 7758 7759 failrec->failed_mirror = failed_mirror; 7760 failrec->this_mirror++; 7761 if (failrec->this_mirror == failed_mirror) 7762 failrec->this_mirror++; 7763 7764 if (failrec->this_mirror > num_copies) { 7765 btrfs_debug(fs_info, 7766 "Check DIO Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d", 7767 num_copies, failrec->this_mirror, failed_mirror); 7768 return 0; 7769 } 7770 7771 return 1; 7772 } 7773 7774 static blk_status_t dio_read_error(struct inode *inode, struct bio *failed_bio, 7775 struct page *page, unsigned int pgoff, 7776 u64 start, u64 end, int failed_mirror, 7777 bio_end_io_t *repair_endio, void *repair_arg) 7778 { 7779 struct io_failure_record *failrec; 7780 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 7781 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree; 7782 struct bio *bio; 7783 int isector; 7784 unsigned int read_mode = 0; 7785 int segs; 7786 int ret; 7787 blk_status_t status; 7788 struct bio_vec bvec; 7789 7790 BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE); 7791 7792 ret = btrfs_get_io_failure_record(inode, start, end, &failrec); 7793 if (ret) 7794 return errno_to_blk_status(ret); 7795 7796 ret = btrfs_check_dio_repairable(inode, failed_bio, failrec, 7797 failed_mirror); 7798 if (!ret) { 7799 free_io_failure(failure_tree, io_tree, failrec); 7800 return BLK_STS_IOERR; 7801 } 7802 7803 segs = bio_segments(failed_bio); 7804 bio_get_first_bvec(failed_bio, &bvec); 7805 if (segs > 1 || 7806 (bvec.bv_len > btrfs_inode_sectorsize(inode))) 7807 read_mode |= REQ_FAILFAST_DEV; 7808 7809 isector = start - btrfs_io_bio(failed_bio)->logical; 7810 isector >>= inode->i_sb->s_blocksize_bits; 7811 bio = btrfs_create_repair_bio(inode, failed_bio, failrec, page, 7812 pgoff, isector, repair_endio, repair_arg); 7813 bio->bi_opf = REQ_OP_READ | read_mode; 7814 7815 btrfs_debug(BTRFS_I(inode)->root->fs_info, 7816 "repair DIO read error: submitting new dio read[%#x] to this_mirror=%d, in_validation=%d", 7817 read_mode, failrec->this_mirror, failrec->in_validation); 7818 7819 status = submit_dio_repair_bio(inode, bio, failrec->this_mirror); 7820 if (status) { 7821 free_io_failure(failure_tree, io_tree, failrec); 7822 bio_put(bio); 7823 } 7824 7825 return status; 7826 } 7827 7828 struct btrfs_retry_complete { 7829 struct completion done; 7830 struct inode *inode; 7831 u64 start; 7832 int uptodate; 7833 }; 7834 7835 static void btrfs_retry_endio_nocsum(struct bio *bio) 7836 { 7837 struct btrfs_retry_complete *done = bio->bi_private; 7838 struct inode *inode = done->inode; 7839 struct bio_vec *bvec; 7840 struct extent_io_tree *io_tree, *failure_tree; 7841 int i; 7842 7843 if (bio->bi_status) 7844 goto end; 7845 7846 ASSERT(bio->bi_vcnt == 1); 7847 io_tree = &BTRFS_I(inode)->io_tree; 7848 failure_tree = &BTRFS_I(inode)->io_failure_tree; 7849 ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(inode)); 7850 7851 done->uptodate = 1; 7852 ASSERT(!bio_flagged(bio, BIO_CLONED)); 7853 bio_for_each_segment_all(bvec, bio, i) 7854 clean_io_failure(BTRFS_I(inode)->root->fs_info, failure_tree, 7855 io_tree, done->start, bvec->bv_page, 7856 btrfs_ino(BTRFS_I(inode)), 0); 7857 end: 7858 complete(&done->done); 7859 bio_put(bio); 7860 } 7861 7862 static blk_status_t __btrfs_correct_data_nocsum(struct inode *inode, 7863 struct btrfs_io_bio *io_bio) 7864 { 7865 struct btrfs_fs_info *fs_info; 7866 struct bio_vec bvec; 7867 struct bvec_iter iter; 7868 struct btrfs_retry_complete done; 7869 u64 start; 7870 unsigned int pgoff; 7871 u32 sectorsize; 7872 int nr_sectors; 7873 blk_status_t ret; 7874 blk_status_t err = BLK_STS_OK; 7875 7876 fs_info = BTRFS_I(inode)->root->fs_info; 7877 sectorsize = fs_info->sectorsize; 7878 7879 start = io_bio->logical; 7880 done.inode = inode; 7881 io_bio->bio.bi_iter = io_bio->iter; 7882 7883 bio_for_each_segment(bvec, &io_bio->bio, iter) { 7884 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len); 7885 pgoff = bvec.bv_offset; 7886 7887 next_block_or_try_again: 7888 done.uptodate = 0; 7889 done.start = start; 7890 init_completion(&done.done); 7891 7892 ret = dio_read_error(inode, &io_bio->bio, bvec.bv_page, 7893 pgoff, start, start + sectorsize - 1, 7894 io_bio->mirror_num, 7895 btrfs_retry_endio_nocsum, &done); 7896 if (ret) { 7897 err = ret; 7898 goto next; 7899 } 7900 7901 wait_for_completion_io(&done.done); 7902 7903 if (!done.uptodate) { 7904 /* We might have another mirror, so try again */ 7905 goto next_block_or_try_again; 7906 } 7907 7908 next: 7909 start += sectorsize; 7910 7911 nr_sectors--; 7912 if (nr_sectors) { 7913 pgoff += sectorsize; 7914 ASSERT(pgoff < PAGE_SIZE); 7915 goto next_block_or_try_again; 7916 } 7917 } 7918 7919 return err; 7920 } 7921 7922 static void btrfs_retry_endio(struct bio *bio) 7923 { 7924 struct btrfs_retry_complete *done = bio->bi_private; 7925 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 7926 struct extent_io_tree *io_tree, *failure_tree; 7927 struct inode *inode = done->inode; 7928 struct bio_vec *bvec; 7929 int uptodate; 7930 int ret; 7931 int i; 7932 7933 if (bio->bi_status) 7934 goto end; 7935 7936 uptodate = 1; 7937 7938 ASSERT(bio->bi_vcnt == 1); 7939 ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(done->inode)); 7940 7941 io_tree = &BTRFS_I(inode)->io_tree; 7942 failure_tree = &BTRFS_I(inode)->io_failure_tree; 7943 7944 ASSERT(!bio_flagged(bio, BIO_CLONED)); 7945 bio_for_each_segment_all(bvec, bio, i) { 7946 ret = __readpage_endio_check(inode, io_bio, i, bvec->bv_page, 7947 bvec->bv_offset, done->start, 7948 bvec->bv_len); 7949 if (!ret) 7950 clean_io_failure(BTRFS_I(inode)->root->fs_info, 7951 failure_tree, io_tree, done->start, 7952 bvec->bv_page, 7953 btrfs_ino(BTRFS_I(inode)), 7954 bvec->bv_offset); 7955 else 7956 uptodate = 0; 7957 } 7958 7959 done->uptodate = uptodate; 7960 end: 7961 complete(&done->done); 7962 bio_put(bio); 7963 } 7964 7965 static blk_status_t __btrfs_subio_endio_read(struct inode *inode, 7966 struct btrfs_io_bio *io_bio, blk_status_t err) 7967 { 7968 struct btrfs_fs_info *fs_info; 7969 struct bio_vec bvec; 7970 struct bvec_iter iter; 7971 struct btrfs_retry_complete done; 7972 u64 start; 7973 u64 offset = 0; 7974 u32 sectorsize; 7975 int nr_sectors; 7976 unsigned int pgoff; 7977 int csum_pos; 7978 bool uptodate = (err == 0); 7979 int ret; 7980 blk_status_t status; 7981 7982 fs_info = BTRFS_I(inode)->root->fs_info; 7983 sectorsize = fs_info->sectorsize; 7984 7985 err = BLK_STS_OK; 7986 start = io_bio->logical; 7987 done.inode = inode; 7988 io_bio->bio.bi_iter = io_bio->iter; 7989 7990 bio_for_each_segment(bvec, &io_bio->bio, iter) { 7991 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len); 7992 7993 pgoff = bvec.bv_offset; 7994 next_block: 7995 if (uptodate) { 7996 csum_pos = BTRFS_BYTES_TO_BLKS(fs_info, offset); 7997 ret = __readpage_endio_check(inode, io_bio, csum_pos, 7998 bvec.bv_page, pgoff, start, sectorsize); 7999 if (likely(!ret)) 8000 goto next; 8001 } 8002 try_again: 8003 done.uptodate = 0; 8004 done.start = start; 8005 init_completion(&done.done); 8006 8007 status = dio_read_error(inode, &io_bio->bio, bvec.bv_page, 8008 pgoff, start, start + sectorsize - 1, 8009 io_bio->mirror_num, btrfs_retry_endio, 8010 &done); 8011 if (status) { 8012 err = status; 8013 goto next; 8014 } 8015 8016 wait_for_completion_io(&done.done); 8017 8018 if (!done.uptodate) { 8019 /* We might have another mirror, so try again */ 8020 goto try_again; 8021 } 8022 next: 8023 offset += sectorsize; 8024 start += sectorsize; 8025 8026 ASSERT(nr_sectors); 8027 8028 nr_sectors--; 8029 if (nr_sectors) { 8030 pgoff += sectorsize; 8031 ASSERT(pgoff < PAGE_SIZE); 8032 goto next_block; 8033 } 8034 } 8035 8036 return err; 8037 } 8038 8039 static blk_status_t btrfs_subio_endio_read(struct inode *inode, 8040 struct btrfs_io_bio *io_bio, blk_status_t err) 8041 { 8042 bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; 8043 8044 if (skip_csum) { 8045 if (unlikely(err)) 8046 return __btrfs_correct_data_nocsum(inode, io_bio); 8047 else 8048 return BLK_STS_OK; 8049 } else { 8050 return __btrfs_subio_endio_read(inode, io_bio, err); 8051 } 8052 } 8053 8054 static void btrfs_endio_direct_read(struct bio *bio) 8055 { 8056 struct btrfs_dio_private *dip = bio->bi_private; 8057 struct inode *inode = dip->inode; 8058 struct bio *dio_bio; 8059 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 8060 blk_status_t err = bio->bi_status; 8061 8062 if (dip->flags & BTRFS_DIO_ORIG_BIO_SUBMITTED) 8063 err = btrfs_subio_endio_read(inode, io_bio, err); 8064 8065 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset, 8066 dip->logical_offset + dip->bytes - 1); 8067 dio_bio = dip->dio_bio; 8068 8069 kfree(dip); 8070 8071 dio_bio->bi_status = err; 8072 dio_end_io(dio_bio); 8073 8074 if (io_bio->end_io) 8075 io_bio->end_io(io_bio, blk_status_to_errno(err)); 8076 bio_put(bio); 8077 } 8078 8079 static void __endio_write_update_ordered(struct inode *inode, 8080 const u64 offset, const u64 bytes, 8081 const bool uptodate) 8082 { 8083 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8084 struct btrfs_ordered_extent *ordered = NULL; 8085 struct btrfs_workqueue *wq; 8086 btrfs_work_func_t func; 8087 u64 ordered_offset = offset; 8088 u64 ordered_bytes = bytes; 8089 u64 last_offset; 8090 8091 if (btrfs_is_free_space_inode(BTRFS_I(inode))) { 8092 wq = fs_info->endio_freespace_worker; 8093 func = btrfs_freespace_write_helper; 8094 } else { 8095 wq = fs_info->endio_write_workers; 8096 func = btrfs_endio_write_helper; 8097 } 8098 8099 while (ordered_offset < offset + bytes) { 8100 last_offset = ordered_offset; 8101 if (btrfs_dec_test_first_ordered_pending(inode, &ordered, 8102 &ordered_offset, 8103 ordered_bytes, 8104 uptodate)) { 8105 btrfs_init_work(&ordered->work, func, 8106 finish_ordered_fn, 8107 NULL, NULL); 8108 btrfs_queue_work(wq, &ordered->work); 8109 } 8110 /* 8111 * If btrfs_dec_test_ordered_pending does not find any ordered 8112 * extent in the range, we can exit. 8113 */ 8114 if (ordered_offset == last_offset) 8115 return; 8116 /* 8117 * Our bio might span multiple ordered extents. In this case 8118 * we keep goin until we have accounted the whole dio. 8119 */ 8120 if (ordered_offset < offset + bytes) { 8121 ordered_bytes = offset + bytes - ordered_offset; 8122 ordered = NULL; 8123 } 8124 } 8125 } 8126 8127 static void btrfs_endio_direct_write(struct bio *bio) 8128 { 8129 struct btrfs_dio_private *dip = bio->bi_private; 8130 struct bio *dio_bio = dip->dio_bio; 8131 8132 __endio_write_update_ordered(dip->inode, dip->logical_offset, 8133 dip->bytes, !bio->bi_status); 8134 8135 kfree(dip); 8136 8137 dio_bio->bi_status = bio->bi_status; 8138 dio_end_io(dio_bio); 8139 bio_put(bio); 8140 } 8141 8142 static blk_status_t btrfs_submit_bio_start_direct_io(void *private_data, 8143 struct bio *bio, u64 offset) 8144 { 8145 struct inode *inode = private_data; 8146 blk_status_t ret; 8147 ret = btrfs_csum_one_bio(inode, bio, offset, 1); 8148 BUG_ON(ret); /* -ENOMEM */ 8149 return 0; 8150 } 8151 8152 static void btrfs_end_dio_bio(struct bio *bio) 8153 { 8154 struct btrfs_dio_private *dip = bio->bi_private; 8155 blk_status_t err = bio->bi_status; 8156 8157 if (err) 8158 btrfs_warn(BTRFS_I(dip->inode)->root->fs_info, 8159 "direct IO failed ino %llu rw %d,%u sector %#Lx len %u err no %d", 8160 btrfs_ino(BTRFS_I(dip->inode)), bio_op(bio), 8161 bio->bi_opf, 8162 (unsigned long long)bio->bi_iter.bi_sector, 8163 bio->bi_iter.bi_size, err); 8164 8165 if (dip->subio_endio) 8166 err = dip->subio_endio(dip->inode, btrfs_io_bio(bio), err); 8167 8168 if (err) { 8169 /* 8170 * We want to perceive the errors flag being set before 8171 * decrementing the reference count. We don't need a barrier 8172 * since atomic operations with a return value are fully 8173 * ordered as per atomic_t.txt 8174 */ 8175 dip->errors = 1; 8176 } 8177 8178 /* if there are more bios still pending for this dio, just exit */ 8179 if (!atomic_dec_and_test(&dip->pending_bios)) 8180 goto out; 8181 8182 if (dip->errors) { 8183 bio_io_error(dip->orig_bio); 8184 } else { 8185 dip->dio_bio->bi_status = BLK_STS_OK; 8186 bio_endio(dip->orig_bio); 8187 } 8188 out: 8189 bio_put(bio); 8190 } 8191 8192 static inline blk_status_t btrfs_lookup_and_bind_dio_csum(struct inode *inode, 8193 struct btrfs_dio_private *dip, 8194 struct bio *bio, 8195 u64 file_offset) 8196 { 8197 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); 8198 struct btrfs_io_bio *orig_io_bio = btrfs_io_bio(dip->orig_bio); 8199 blk_status_t ret; 8200 8201 /* 8202 * We load all the csum data we need when we submit 8203 * the first bio to reduce the csum tree search and 8204 * contention. 8205 */ 8206 if (dip->logical_offset == file_offset) { 8207 ret = btrfs_lookup_bio_sums_dio(inode, dip->orig_bio, 8208 file_offset); 8209 if (ret) 8210 return ret; 8211 } 8212 8213 if (bio == dip->orig_bio) 8214 return 0; 8215 8216 file_offset -= dip->logical_offset; 8217 file_offset >>= inode->i_sb->s_blocksize_bits; 8218 io_bio->csum = (u8 *)(((u32 *)orig_io_bio->csum) + file_offset); 8219 8220 return 0; 8221 } 8222 8223 static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio, 8224 struct inode *inode, u64 file_offset, int async_submit) 8225 { 8226 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8227 struct btrfs_dio_private *dip = bio->bi_private; 8228 bool write = bio_op(bio) == REQ_OP_WRITE; 8229 blk_status_t ret; 8230 8231 /* Check btrfs_submit_bio_hook() for rules about async submit. */ 8232 if (async_submit) 8233 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers); 8234 8235 if (!write) { 8236 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA); 8237 if (ret) 8238 goto err; 8239 } 8240 8241 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) 8242 goto map; 8243 8244 if (write && async_submit) { 8245 ret = btrfs_wq_submit_bio(fs_info, bio, 0, 0, 8246 file_offset, inode, 8247 btrfs_submit_bio_start_direct_io); 8248 goto err; 8249 } else if (write) { 8250 /* 8251 * If we aren't doing async submit, calculate the csum of the 8252 * bio now. 8253 */ 8254 ret = btrfs_csum_one_bio(inode, bio, file_offset, 1); 8255 if (ret) 8256 goto err; 8257 } else { 8258 ret = btrfs_lookup_and_bind_dio_csum(inode, dip, bio, 8259 file_offset); 8260 if (ret) 8261 goto err; 8262 } 8263 map: 8264 ret = btrfs_map_bio(fs_info, bio, 0, 0); 8265 err: 8266 return ret; 8267 } 8268 8269 static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip) 8270 { 8271 struct inode *inode = dip->inode; 8272 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8273 struct bio *bio; 8274 struct bio *orig_bio = dip->orig_bio; 8275 u64 start_sector = orig_bio->bi_iter.bi_sector; 8276 u64 file_offset = dip->logical_offset; 8277 u64 map_length; 8278 int async_submit = 0; 8279 u64 submit_len; 8280 int clone_offset = 0; 8281 int clone_len; 8282 int ret; 8283 blk_status_t status; 8284 8285 map_length = orig_bio->bi_iter.bi_size; 8286 submit_len = map_length; 8287 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9, 8288 &map_length, NULL, 0); 8289 if (ret) 8290 return -EIO; 8291 8292 if (map_length >= submit_len) { 8293 bio = orig_bio; 8294 dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED; 8295 goto submit; 8296 } 8297 8298 /* async crcs make it difficult to collect full stripe writes. */ 8299 if (btrfs_data_alloc_profile(fs_info) & BTRFS_BLOCK_GROUP_RAID56_MASK) 8300 async_submit = 0; 8301 else 8302 async_submit = 1; 8303 8304 /* bio split */ 8305 ASSERT(map_length <= INT_MAX); 8306 atomic_inc(&dip->pending_bios); 8307 do { 8308 clone_len = min_t(int, submit_len, map_length); 8309 8310 /* 8311 * This will never fail as it's passing GPF_NOFS and 8312 * the allocation is backed by btrfs_bioset. 8313 */ 8314 bio = btrfs_bio_clone_partial(orig_bio, clone_offset, 8315 clone_len); 8316 bio->bi_private = dip; 8317 bio->bi_end_io = btrfs_end_dio_bio; 8318 btrfs_io_bio(bio)->logical = file_offset; 8319 8320 ASSERT(submit_len >= clone_len); 8321 submit_len -= clone_len; 8322 if (submit_len == 0) 8323 break; 8324 8325 /* 8326 * Increase the count before we submit the bio so we know 8327 * the end IO handler won't happen before we increase the 8328 * count. Otherwise, the dip might get freed before we're 8329 * done setting it up. 8330 */ 8331 atomic_inc(&dip->pending_bios); 8332 8333 status = btrfs_submit_dio_bio(bio, inode, file_offset, 8334 async_submit); 8335 if (status) { 8336 bio_put(bio); 8337 atomic_dec(&dip->pending_bios); 8338 goto out_err; 8339 } 8340 8341 clone_offset += clone_len; 8342 start_sector += clone_len >> 9; 8343 file_offset += clone_len; 8344 8345 map_length = submit_len; 8346 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), 8347 start_sector << 9, &map_length, NULL, 0); 8348 if (ret) 8349 goto out_err; 8350 } while (submit_len > 0); 8351 8352 submit: 8353 status = btrfs_submit_dio_bio(bio, inode, file_offset, async_submit); 8354 if (!status) 8355 return 0; 8356 8357 bio_put(bio); 8358 out_err: 8359 dip->errors = 1; 8360 /* 8361 * Before atomic variable goto zero, we must make sure dip->errors is 8362 * perceived to be set. This ordering is ensured by the fact that an 8363 * atomic operations with a return value are fully ordered as per 8364 * atomic_t.txt 8365 */ 8366 if (atomic_dec_and_test(&dip->pending_bios)) 8367 bio_io_error(dip->orig_bio); 8368 8369 /* bio_end_io() will handle error, so we needn't return it */ 8370 return 0; 8371 } 8372 8373 static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode, 8374 loff_t file_offset) 8375 { 8376 struct btrfs_dio_private *dip = NULL; 8377 struct bio *bio = NULL; 8378 struct btrfs_io_bio *io_bio; 8379 bool write = (bio_op(dio_bio) == REQ_OP_WRITE); 8380 int ret = 0; 8381 8382 bio = btrfs_bio_clone(dio_bio); 8383 8384 dip = kzalloc(sizeof(*dip), GFP_NOFS); 8385 if (!dip) { 8386 ret = -ENOMEM; 8387 goto free_ordered; 8388 } 8389 8390 dip->private = dio_bio->bi_private; 8391 dip->inode = inode; 8392 dip->logical_offset = file_offset; 8393 dip->bytes = dio_bio->bi_iter.bi_size; 8394 dip->disk_bytenr = (u64)dio_bio->bi_iter.bi_sector << 9; 8395 bio->bi_private = dip; 8396 dip->orig_bio = bio; 8397 dip->dio_bio = dio_bio; 8398 atomic_set(&dip->pending_bios, 0); 8399 io_bio = btrfs_io_bio(bio); 8400 io_bio->logical = file_offset; 8401 8402 if (write) { 8403 bio->bi_end_io = btrfs_endio_direct_write; 8404 } else { 8405 bio->bi_end_io = btrfs_endio_direct_read; 8406 dip->subio_endio = btrfs_subio_endio_read; 8407 } 8408 8409 /* 8410 * Reset the range for unsubmitted ordered extents (to a 0 length range) 8411 * even if we fail to submit a bio, because in such case we do the 8412 * corresponding error handling below and it must not be done a second 8413 * time by btrfs_direct_IO(). 8414 */ 8415 if (write) { 8416 struct btrfs_dio_data *dio_data = current->journal_info; 8417 8418 dio_data->unsubmitted_oe_range_end = dip->logical_offset + 8419 dip->bytes; 8420 dio_data->unsubmitted_oe_range_start = 8421 dio_data->unsubmitted_oe_range_end; 8422 } 8423 8424 ret = btrfs_submit_direct_hook(dip); 8425 if (!ret) 8426 return; 8427 8428 if (io_bio->end_io) 8429 io_bio->end_io(io_bio, ret); 8430 8431 free_ordered: 8432 /* 8433 * If we arrived here it means either we failed to submit the dip 8434 * or we either failed to clone the dio_bio or failed to allocate the 8435 * dip. If we cloned the dio_bio and allocated the dip, we can just 8436 * call bio_endio against our io_bio so that we get proper resource 8437 * cleanup if we fail to submit the dip, otherwise, we must do the 8438 * same as btrfs_endio_direct_[write|read] because we can't call these 8439 * callbacks - they require an allocated dip and a clone of dio_bio. 8440 */ 8441 if (bio && dip) { 8442 bio_io_error(bio); 8443 /* 8444 * The end io callbacks free our dip, do the final put on bio 8445 * and all the cleanup and final put for dio_bio (through 8446 * dio_end_io()). 8447 */ 8448 dip = NULL; 8449 bio = NULL; 8450 } else { 8451 if (write) 8452 __endio_write_update_ordered(inode, 8453 file_offset, 8454 dio_bio->bi_iter.bi_size, 8455 false); 8456 else 8457 unlock_extent(&BTRFS_I(inode)->io_tree, file_offset, 8458 file_offset + dio_bio->bi_iter.bi_size - 1); 8459 8460 dio_bio->bi_status = BLK_STS_IOERR; 8461 /* 8462 * Releases and cleans up our dio_bio, no need to bio_put() 8463 * nor bio_endio()/bio_io_error() against dio_bio. 8464 */ 8465 dio_end_io(dio_bio); 8466 } 8467 if (bio) 8468 bio_put(bio); 8469 kfree(dip); 8470 } 8471 8472 static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info, 8473 const struct iov_iter *iter, loff_t offset) 8474 { 8475 int seg; 8476 int i; 8477 unsigned int blocksize_mask = fs_info->sectorsize - 1; 8478 ssize_t retval = -EINVAL; 8479 8480 if (offset & blocksize_mask) 8481 goto out; 8482 8483 if (iov_iter_alignment(iter) & blocksize_mask) 8484 goto out; 8485 8486 /* If this is a write we don't need to check anymore */ 8487 if (iov_iter_rw(iter) != READ || !iter_is_iovec(iter)) 8488 return 0; 8489 /* 8490 * Check to make sure we don't have duplicate iov_base's in this 8491 * iovec, if so return EINVAL, otherwise we'll get csum errors 8492 * when reading back. 8493 */ 8494 for (seg = 0; seg < iter->nr_segs; seg++) { 8495 for (i = seg + 1; i < iter->nr_segs; i++) { 8496 if (iter->iov[seg].iov_base == iter->iov[i].iov_base) 8497 goto out; 8498 } 8499 } 8500 retval = 0; 8501 out: 8502 return retval; 8503 } 8504 8505 static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) 8506 { 8507 struct file *file = iocb->ki_filp; 8508 struct inode *inode = file->f_mapping->host; 8509 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8510 struct btrfs_dio_data dio_data = { 0 }; 8511 struct extent_changeset *data_reserved = NULL; 8512 loff_t offset = iocb->ki_pos; 8513 size_t count = 0; 8514 int flags = 0; 8515 bool wakeup = true; 8516 bool relock = false; 8517 ssize_t ret; 8518 8519 if (check_direct_IO(fs_info, iter, offset)) 8520 return 0; 8521 8522 inode_dio_begin(inode); 8523 8524 /* 8525 * The generic stuff only does filemap_write_and_wait_range, which 8526 * isn't enough if we've written compressed pages to this area, so 8527 * we need to flush the dirty pages again to make absolutely sure 8528 * that any outstanding dirty pages are on disk. 8529 */ 8530 count = iov_iter_count(iter); 8531 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 8532 &BTRFS_I(inode)->runtime_flags)) 8533 filemap_fdatawrite_range(inode->i_mapping, offset, 8534 offset + count - 1); 8535 8536 if (iov_iter_rw(iter) == WRITE) { 8537 /* 8538 * If the write DIO is beyond the EOF, we need update 8539 * the isize, but it is protected by i_mutex. So we can 8540 * not unlock the i_mutex at this case. 8541 */ 8542 if (offset + count <= inode->i_size) { 8543 dio_data.overwrite = 1; 8544 inode_unlock(inode); 8545 relock = true; 8546 } else if (iocb->ki_flags & IOCB_NOWAIT) { 8547 ret = -EAGAIN; 8548 goto out; 8549 } 8550 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, 8551 offset, count); 8552 if (ret) 8553 goto out; 8554 8555 /* 8556 * We need to know how many extents we reserved so that we can 8557 * do the accounting properly if we go over the number we 8558 * originally calculated. Abuse current->journal_info for this. 8559 */ 8560 dio_data.reserve = round_up(count, 8561 fs_info->sectorsize); 8562 dio_data.unsubmitted_oe_range_start = (u64)offset; 8563 dio_data.unsubmitted_oe_range_end = (u64)offset; 8564 current->journal_info = &dio_data; 8565 down_read(&BTRFS_I(inode)->dio_sem); 8566 } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK, 8567 &BTRFS_I(inode)->runtime_flags)) { 8568 inode_dio_end(inode); 8569 flags = DIO_LOCKING | DIO_SKIP_HOLES; 8570 wakeup = false; 8571 } 8572 8573 ret = __blockdev_direct_IO(iocb, inode, 8574 fs_info->fs_devices->latest_bdev, 8575 iter, btrfs_get_blocks_direct, NULL, 8576 btrfs_submit_direct, flags); 8577 if (iov_iter_rw(iter) == WRITE) { 8578 up_read(&BTRFS_I(inode)->dio_sem); 8579 current->journal_info = NULL; 8580 if (ret < 0 && ret != -EIOCBQUEUED) { 8581 if (dio_data.reserve) 8582 btrfs_delalloc_release_space(inode, data_reserved, 8583 offset, dio_data.reserve, true); 8584 /* 8585 * On error we might have left some ordered extents 8586 * without submitting corresponding bios for them, so 8587 * cleanup them up to avoid other tasks getting them 8588 * and waiting for them to complete forever. 8589 */ 8590 if (dio_data.unsubmitted_oe_range_start < 8591 dio_data.unsubmitted_oe_range_end) 8592 __endio_write_update_ordered(inode, 8593 dio_data.unsubmitted_oe_range_start, 8594 dio_data.unsubmitted_oe_range_end - 8595 dio_data.unsubmitted_oe_range_start, 8596 false); 8597 } else if (ret >= 0 && (size_t)ret < count) 8598 btrfs_delalloc_release_space(inode, data_reserved, 8599 offset, count - (size_t)ret, true); 8600 btrfs_delalloc_release_extents(BTRFS_I(inode), count, false); 8601 } 8602 out: 8603 if (wakeup) 8604 inode_dio_end(inode); 8605 if (relock) 8606 inode_lock(inode); 8607 8608 extent_changeset_free(data_reserved); 8609 return ret; 8610 } 8611 8612 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC) 8613 8614 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, 8615 __u64 start, __u64 len) 8616 { 8617 int ret; 8618 8619 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS); 8620 if (ret) 8621 return ret; 8622 8623 return extent_fiemap(inode, fieinfo, start, len); 8624 } 8625 8626 int btrfs_readpage(struct file *file, struct page *page) 8627 { 8628 struct extent_io_tree *tree; 8629 tree = &BTRFS_I(page->mapping->host)->io_tree; 8630 return extent_read_full_page(tree, page, btrfs_get_extent, 0); 8631 } 8632 8633 static int btrfs_writepage(struct page *page, struct writeback_control *wbc) 8634 { 8635 struct inode *inode = page->mapping->host; 8636 int ret; 8637 8638 if (current->flags & PF_MEMALLOC) { 8639 redirty_page_for_writepage(wbc, page); 8640 unlock_page(page); 8641 return 0; 8642 } 8643 8644 /* 8645 * If we are under memory pressure we will call this directly from the 8646 * VM, we need to make sure we have the inode referenced for the ordered 8647 * extent. If not just return like we didn't do anything. 8648 */ 8649 if (!igrab(inode)) { 8650 redirty_page_for_writepage(wbc, page); 8651 return AOP_WRITEPAGE_ACTIVATE; 8652 } 8653 ret = extent_write_full_page(page, wbc); 8654 btrfs_add_delayed_iput(inode); 8655 return ret; 8656 } 8657 8658 static int btrfs_writepages(struct address_space *mapping, 8659 struct writeback_control *wbc) 8660 { 8661 return extent_writepages(mapping, wbc); 8662 } 8663 8664 static int 8665 btrfs_readpages(struct file *file, struct address_space *mapping, 8666 struct list_head *pages, unsigned nr_pages) 8667 { 8668 return extent_readpages(mapping, pages, nr_pages); 8669 } 8670 8671 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) 8672 { 8673 int ret = try_release_extent_mapping(page, gfp_flags); 8674 if (ret == 1) { 8675 ClearPagePrivate(page); 8676 set_page_private(page, 0); 8677 put_page(page); 8678 } 8679 return ret; 8680 } 8681 8682 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) 8683 { 8684 if (PageWriteback(page) || PageDirty(page)) 8685 return 0; 8686 return __btrfs_releasepage(page, gfp_flags); 8687 } 8688 8689 static void btrfs_invalidatepage(struct page *page, unsigned int offset, 8690 unsigned int length) 8691 { 8692 struct inode *inode = page->mapping->host; 8693 struct extent_io_tree *tree; 8694 struct btrfs_ordered_extent *ordered; 8695 struct extent_state *cached_state = NULL; 8696 u64 page_start = page_offset(page); 8697 u64 page_end = page_start + PAGE_SIZE - 1; 8698 u64 start; 8699 u64 end; 8700 int inode_evicting = inode->i_state & I_FREEING; 8701 8702 /* 8703 * we have the page locked, so new writeback can't start, 8704 * and the dirty bit won't be cleared while we are here. 8705 * 8706 * Wait for IO on this page so that we can safely clear 8707 * the PagePrivate2 bit and do ordered accounting 8708 */ 8709 wait_on_page_writeback(page); 8710 8711 tree = &BTRFS_I(inode)->io_tree; 8712 if (offset) { 8713 btrfs_releasepage(page, GFP_NOFS); 8714 return; 8715 } 8716 8717 if (!inode_evicting) 8718 lock_extent_bits(tree, page_start, page_end, &cached_state); 8719 again: 8720 start = page_start; 8721 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start, 8722 page_end - start + 1); 8723 if (ordered) { 8724 end = min(page_end, ordered->file_offset + ordered->len - 1); 8725 /* 8726 * IO on this page will never be started, so we need 8727 * to account for any ordered extents now 8728 */ 8729 if (!inode_evicting) 8730 clear_extent_bit(tree, start, end, 8731 EXTENT_DIRTY | EXTENT_DELALLOC | 8732 EXTENT_DELALLOC_NEW | 8733 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING | 8734 EXTENT_DEFRAG, 1, 0, &cached_state); 8735 /* 8736 * whoever cleared the private bit is responsible 8737 * for the finish_ordered_io 8738 */ 8739 if (TestClearPagePrivate2(page)) { 8740 struct btrfs_ordered_inode_tree *tree; 8741 u64 new_len; 8742 8743 tree = &BTRFS_I(inode)->ordered_tree; 8744 8745 spin_lock_irq(&tree->lock); 8746 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); 8747 new_len = start - ordered->file_offset; 8748 if (new_len < ordered->truncated_len) 8749 ordered->truncated_len = new_len; 8750 spin_unlock_irq(&tree->lock); 8751 8752 if (btrfs_dec_test_ordered_pending(inode, &ordered, 8753 start, 8754 end - start + 1, 1)) 8755 btrfs_finish_ordered_io(ordered); 8756 } 8757 btrfs_put_ordered_extent(ordered); 8758 if (!inode_evicting) { 8759 cached_state = NULL; 8760 lock_extent_bits(tree, start, end, 8761 &cached_state); 8762 } 8763 8764 start = end + 1; 8765 if (start < page_end) 8766 goto again; 8767 } 8768 8769 /* 8770 * Qgroup reserved space handler 8771 * Page here will be either 8772 * 1) Already written to disk 8773 * In this case, its reserved space is released from data rsv map 8774 * and will be freed by delayed_ref handler finally. 8775 * So even we call qgroup_free_data(), it won't decrease reserved 8776 * space. 8777 * 2) Not written to disk 8778 * This means the reserved space should be freed here. However, 8779 * if a truncate invalidates the page (by clearing PageDirty) 8780 * and the page is accounted for while allocating extent 8781 * in btrfs_check_data_free_space() we let delayed_ref to 8782 * free the entire extent. 8783 */ 8784 if (PageDirty(page)) 8785 btrfs_qgroup_free_data(inode, NULL, page_start, PAGE_SIZE); 8786 if (!inode_evicting) { 8787 clear_extent_bit(tree, page_start, page_end, 8788 EXTENT_LOCKED | EXTENT_DIRTY | 8789 EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | 8790 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1, 8791 &cached_state); 8792 8793 __btrfs_releasepage(page, GFP_NOFS); 8794 } 8795 8796 ClearPageChecked(page); 8797 if (PagePrivate(page)) { 8798 ClearPagePrivate(page); 8799 set_page_private(page, 0); 8800 put_page(page); 8801 } 8802 } 8803 8804 /* 8805 * btrfs_page_mkwrite() is not allowed to change the file size as it gets 8806 * called from a page fault handler when a page is first dirtied. Hence we must 8807 * be careful to check for EOF conditions here. We set the page up correctly 8808 * for a written page which means we get ENOSPC checking when writing into 8809 * holes and correct delalloc and unwritten extent mapping on filesystems that 8810 * support these features. 8811 * 8812 * We are not allowed to take the i_mutex here so we have to play games to 8813 * protect against truncate races as the page could now be beyond EOF. Because 8814 * truncate_setsize() writes the inode size before removing pages, once we have 8815 * the page lock we can determine safely if the page is beyond EOF. If it is not 8816 * beyond EOF, then the page is guaranteed safe against truncation until we 8817 * unlock the page. 8818 */ 8819 vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) 8820 { 8821 struct page *page = vmf->page; 8822 struct inode *inode = file_inode(vmf->vma->vm_file); 8823 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8824 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; 8825 struct btrfs_ordered_extent *ordered; 8826 struct extent_state *cached_state = NULL; 8827 struct extent_changeset *data_reserved = NULL; 8828 char *kaddr; 8829 unsigned long zero_start; 8830 loff_t size; 8831 vm_fault_t ret; 8832 int ret2; 8833 int reserved = 0; 8834 u64 reserved_space; 8835 u64 page_start; 8836 u64 page_end; 8837 u64 end; 8838 8839 reserved_space = PAGE_SIZE; 8840 8841 sb_start_pagefault(inode->i_sb); 8842 page_start = page_offset(page); 8843 page_end = page_start + PAGE_SIZE - 1; 8844 end = page_end; 8845 8846 /* 8847 * Reserving delalloc space after obtaining the page lock can lead to 8848 * deadlock. For example, if a dirty page is locked by this function 8849 * and the call to btrfs_delalloc_reserve_space() ends up triggering 8850 * dirty page write out, then the btrfs_writepage() function could 8851 * end up waiting indefinitely to get a lock on the page currently 8852 * being processed by btrfs_page_mkwrite() function. 8853 */ 8854 ret2 = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, 8855 reserved_space); 8856 if (!ret2) { 8857 ret2 = file_update_time(vmf->vma->vm_file); 8858 reserved = 1; 8859 } 8860 if (ret2) { 8861 ret = vmf_error(ret2); 8862 if (reserved) 8863 goto out; 8864 goto out_noreserve; 8865 } 8866 8867 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ 8868 again: 8869 lock_page(page); 8870 size = i_size_read(inode); 8871 8872 if ((page->mapping != inode->i_mapping) || 8873 (page_start >= size)) { 8874 /* page got truncated out from underneath us */ 8875 goto out_unlock; 8876 } 8877 wait_on_page_writeback(page); 8878 8879 lock_extent_bits(io_tree, page_start, page_end, &cached_state); 8880 set_page_extent_mapped(page); 8881 8882 /* 8883 * we can't set the delalloc bits if there are pending ordered 8884 * extents. Drop our locks and wait for them to finish 8885 */ 8886 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start, 8887 PAGE_SIZE); 8888 if (ordered) { 8889 unlock_extent_cached(io_tree, page_start, page_end, 8890 &cached_state); 8891 unlock_page(page); 8892 btrfs_start_ordered_extent(inode, ordered, 1); 8893 btrfs_put_ordered_extent(ordered); 8894 goto again; 8895 } 8896 8897 if (page->index == ((size - 1) >> PAGE_SHIFT)) { 8898 reserved_space = round_up(size - page_start, 8899 fs_info->sectorsize); 8900 if (reserved_space < PAGE_SIZE) { 8901 end = page_start + reserved_space - 1; 8902 btrfs_delalloc_release_space(inode, data_reserved, 8903 page_start, PAGE_SIZE - reserved_space, 8904 true); 8905 } 8906 } 8907 8908 /* 8909 * page_mkwrite gets called when the page is firstly dirtied after it's 8910 * faulted in, but write(2) could also dirty a page and set delalloc 8911 * bits, thus in this case for space account reason, we still need to 8912 * clear any delalloc bits within this page range since we have to 8913 * reserve data&meta space before lock_page() (see above comments). 8914 */ 8915 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, end, 8916 EXTENT_DIRTY | EXTENT_DELALLOC | 8917 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 8918 0, 0, &cached_state); 8919 8920 ret2 = btrfs_set_extent_delalloc(inode, page_start, end, 0, 8921 &cached_state, 0); 8922 if (ret2) { 8923 unlock_extent_cached(io_tree, page_start, page_end, 8924 &cached_state); 8925 ret = VM_FAULT_SIGBUS; 8926 goto out_unlock; 8927 } 8928 ret2 = 0; 8929 8930 /* page is wholly or partially inside EOF */ 8931 if (page_start + PAGE_SIZE > size) 8932 zero_start = size & ~PAGE_MASK; 8933 else 8934 zero_start = PAGE_SIZE; 8935 8936 if (zero_start != PAGE_SIZE) { 8937 kaddr = kmap(page); 8938 memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start); 8939 flush_dcache_page(page); 8940 kunmap(page); 8941 } 8942 ClearPageChecked(page); 8943 set_page_dirty(page); 8944 SetPageUptodate(page); 8945 8946 BTRFS_I(inode)->last_trans = fs_info->generation; 8947 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid; 8948 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit; 8949 8950 unlock_extent_cached(io_tree, page_start, page_end, &cached_state); 8951 8952 if (!ret2) { 8953 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, true); 8954 sb_end_pagefault(inode->i_sb); 8955 extent_changeset_free(data_reserved); 8956 return VM_FAULT_LOCKED; 8957 } 8958 8959 out_unlock: 8960 unlock_page(page); 8961 out: 8962 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, (ret != 0)); 8963 btrfs_delalloc_release_space(inode, data_reserved, page_start, 8964 reserved_space, (ret != 0)); 8965 out_noreserve: 8966 sb_end_pagefault(inode->i_sb); 8967 extent_changeset_free(data_reserved); 8968 return ret; 8969 } 8970 8971 static int btrfs_truncate(struct inode *inode, bool skip_writeback) 8972 { 8973 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 8974 struct btrfs_root *root = BTRFS_I(inode)->root; 8975 struct btrfs_block_rsv *rsv; 8976 int ret; 8977 struct btrfs_trans_handle *trans; 8978 u64 mask = fs_info->sectorsize - 1; 8979 u64 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1); 8980 8981 if (!skip_writeback) { 8982 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask), 8983 (u64)-1); 8984 if (ret) 8985 return ret; 8986 } 8987 8988 /* 8989 * Yes ladies and gentlemen, this is indeed ugly. We have a couple of 8990 * things going on here: 8991 * 8992 * 1) We need to reserve space to update our inode. 8993 * 8994 * 2) We need to have something to cache all the space that is going to 8995 * be free'd up by the truncate operation, but also have some slack 8996 * space reserved in case it uses space during the truncate (thank you 8997 * very much snapshotting). 8998 * 8999 * And we need these to be separate. The fact is we can use a lot of 9000 * space doing the truncate, and we have no earthly idea how much space 9001 * we will use, so we need the truncate reservation to be separate so it 9002 * doesn't end up using space reserved for updating the inode. We also 9003 * need to be able to stop the transaction and start a new one, which 9004 * means we need to be able to update the inode several times, and we 9005 * have no idea of knowing how many times that will be, so we can't just 9006 * reserve 1 item for the entirety of the operation, so that has to be 9007 * done separately as well. 9008 * 9009 * So that leaves us with 9010 * 9011 * 1) rsv - for the truncate reservation, which we will steal from the 9012 * transaction reservation. 9013 * 2) fs_info->trans_block_rsv - this will have 1 items worth left for 9014 * updating the inode. 9015 */ 9016 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); 9017 if (!rsv) 9018 return -ENOMEM; 9019 rsv->size = min_size; 9020 rsv->failfast = 1; 9021 9022 /* 9023 * 1 for the truncate slack space 9024 * 1 for updating the inode. 9025 */ 9026 trans = btrfs_start_transaction(root, 2); 9027 if (IS_ERR(trans)) { 9028 ret = PTR_ERR(trans); 9029 goto out; 9030 } 9031 9032 /* Migrate the slack space for the truncate to our reserve */ 9033 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv, 9034 min_size, 0); 9035 BUG_ON(ret); 9036 9037 /* 9038 * So if we truncate and then write and fsync we normally would just 9039 * write the extents that changed, which is a problem if we need to 9040 * first truncate that entire inode. So set this flag so we write out 9041 * all of the extents in the inode to the sync log so we're completely 9042 * safe. 9043 */ 9044 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); 9045 trans->block_rsv = rsv; 9046 9047 while (1) { 9048 ret = btrfs_truncate_inode_items(trans, root, inode, 9049 inode->i_size, 9050 BTRFS_EXTENT_DATA_KEY); 9051 trans->block_rsv = &fs_info->trans_block_rsv; 9052 if (ret != -ENOSPC && ret != -EAGAIN) 9053 break; 9054 9055 ret = btrfs_update_inode(trans, root, inode); 9056 if (ret) 9057 break; 9058 9059 btrfs_end_transaction(trans); 9060 btrfs_btree_balance_dirty(fs_info); 9061 9062 trans = btrfs_start_transaction(root, 2); 9063 if (IS_ERR(trans)) { 9064 ret = PTR_ERR(trans); 9065 trans = NULL; 9066 break; 9067 } 9068 9069 btrfs_block_rsv_release(fs_info, rsv, -1); 9070 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, 9071 rsv, min_size, 0); 9072 BUG_ON(ret); /* shouldn't happen */ 9073 trans->block_rsv = rsv; 9074 } 9075 9076 /* 9077 * We can't call btrfs_truncate_block inside a trans handle as we could 9078 * deadlock with freeze, if we got NEED_TRUNCATE_BLOCK then we know 9079 * we've truncated everything except the last little bit, and can do 9080 * btrfs_truncate_block and then update the disk_i_size. 9081 */ 9082 if (ret == NEED_TRUNCATE_BLOCK) { 9083 btrfs_end_transaction(trans); 9084 btrfs_btree_balance_dirty(fs_info); 9085 9086 ret = btrfs_truncate_block(inode, inode->i_size, 0, 0); 9087 if (ret) 9088 goto out; 9089 trans = btrfs_start_transaction(root, 1); 9090 if (IS_ERR(trans)) { 9091 ret = PTR_ERR(trans); 9092 goto out; 9093 } 9094 btrfs_ordered_update_i_size(inode, inode->i_size, NULL); 9095 } 9096 9097 if (trans) { 9098 int ret2; 9099 9100 trans->block_rsv = &fs_info->trans_block_rsv; 9101 ret2 = btrfs_update_inode(trans, root, inode); 9102 if (ret2 && !ret) 9103 ret = ret2; 9104 9105 ret2 = btrfs_end_transaction(trans); 9106 if (ret2 && !ret) 9107 ret = ret2; 9108 btrfs_btree_balance_dirty(fs_info); 9109 } 9110 out: 9111 btrfs_free_block_rsv(fs_info, rsv); 9112 9113 return ret; 9114 } 9115 9116 /* 9117 * create a new subvolume directory/inode (helper for the ioctl). 9118 */ 9119 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, 9120 struct btrfs_root *new_root, 9121 struct btrfs_root *parent_root, 9122 u64 new_dirid) 9123 { 9124 struct inode *inode; 9125 int err; 9126 u64 index = 0; 9127 9128 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, 9129 new_dirid, new_dirid, 9130 S_IFDIR | (~current_umask() & S_IRWXUGO), 9131 &index); 9132 if (IS_ERR(inode)) 9133 return PTR_ERR(inode); 9134 inode->i_op = &btrfs_dir_inode_operations; 9135 inode->i_fop = &btrfs_dir_file_operations; 9136 9137 set_nlink(inode, 1); 9138 btrfs_i_size_write(BTRFS_I(inode), 0); 9139 unlock_new_inode(inode); 9140 9141 err = btrfs_subvol_inherit_props(trans, new_root, parent_root); 9142 if (err) 9143 btrfs_err(new_root->fs_info, 9144 "error inheriting subvolume %llu properties: %d", 9145 new_root->root_key.objectid, err); 9146 9147 err = btrfs_update_inode(trans, new_root, inode); 9148 9149 iput(inode); 9150 return err; 9151 } 9152 9153 struct inode *btrfs_alloc_inode(struct super_block *sb) 9154 { 9155 struct btrfs_fs_info *fs_info = btrfs_sb(sb); 9156 struct btrfs_inode *ei; 9157 struct inode *inode; 9158 9159 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_KERNEL); 9160 if (!ei) 9161 return NULL; 9162 9163 ei->root = NULL; 9164 ei->generation = 0; 9165 ei->last_trans = 0; 9166 ei->last_sub_trans = 0; 9167 ei->logged_trans = 0; 9168 ei->delalloc_bytes = 0; 9169 ei->new_delalloc_bytes = 0; 9170 ei->defrag_bytes = 0; 9171 ei->disk_i_size = 0; 9172 ei->flags = 0; 9173 ei->csum_bytes = 0; 9174 ei->index_cnt = (u64)-1; 9175 ei->dir_index = 0; 9176 ei->last_unlink_trans = 0; 9177 ei->last_log_commit = 0; 9178 9179 spin_lock_init(&ei->lock); 9180 ei->outstanding_extents = 0; 9181 if (sb->s_magic != BTRFS_TEST_MAGIC) 9182 btrfs_init_metadata_block_rsv(fs_info, &ei->block_rsv, 9183 BTRFS_BLOCK_RSV_DELALLOC); 9184 ei->runtime_flags = 0; 9185 ei->prop_compress = BTRFS_COMPRESS_NONE; 9186 ei->defrag_compress = BTRFS_COMPRESS_NONE; 9187 9188 ei->delayed_node = NULL; 9189 9190 ei->i_otime.tv_sec = 0; 9191 ei->i_otime.tv_nsec = 0; 9192 9193 inode = &ei->vfs_inode; 9194 extent_map_tree_init(&ei->extent_tree); 9195 extent_io_tree_init(&ei->io_tree, inode); 9196 extent_io_tree_init(&ei->io_failure_tree, inode); 9197 ei->io_tree.track_uptodate = 1; 9198 ei->io_failure_tree.track_uptodate = 1; 9199 atomic_set(&ei->sync_writers, 0); 9200 mutex_init(&ei->log_mutex); 9201 mutex_init(&ei->delalloc_mutex); 9202 btrfs_ordered_inode_tree_init(&ei->ordered_tree); 9203 INIT_LIST_HEAD(&ei->delalloc_inodes); 9204 INIT_LIST_HEAD(&ei->delayed_iput); 9205 RB_CLEAR_NODE(&ei->rb_node); 9206 init_rwsem(&ei->dio_sem); 9207 9208 return inode; 9209 } 9210 9211 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 9212 void btrfs_test_destroy_inode(struct inode *inode) 9213 { 9214 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0); 9215 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); 9216 } 9217 #endif 9218 9219 static void btrfs_i_callback(struct rcu_head *head) 9220 { 9221 struct inode *inode = container_of(head, struct inode, i_rcu); 9222 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); 9223 } 9224 9225 void btrfs_destroy_inode(struct inode *inode) 9226 { 9227 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 9228 struct btrfs_ordered_extent *ordered; 9229 struct btrfs_root *root = BTRFS_I(inode)->root; 9230 9231 WARN_ON(!hlist_empty(&inode->i_dentry)); 9232 WARN_ON(inode->i_data.nrpages); 9233 WARN_ON(BTRFS_I(inode)->block_rsv.reserved); 9234 WARN_ON(BTRFS_I(inode)->block_rsv.size); 9235 WARN_ON(BTRFS_I(inode)->outstanding_extents); 9236 WARN_ON(BTRFS_I(inode)->delalloc_bytes); 9237 WARN_ON(BTRFS_I(inode)->new_delalloc_bytes); 9238 WARN_ON(BTRFS_I(inode)->csum_bytes); 9239 WARN_ON(BTRFS_I(inode)->defrag_bytes); 9240 9241 /* 9242 * This can happen where we create an inode, but somebody else also 9243 * created the same inode and we need to destroy the one we already 9244 * created. 9245 */ 9246 if (!root) 9247 goto free; 9248 9249 while (1) { 9250 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1); 9251 if (!ordered) 9252 break; 9253 else { 9254 btrfs_err(fs_info, 9255 "found ordered extent %llu %llu on inode cleanup", 9256 ordered->file_offset, ordered->len); 9257 btrfs_remove_ordered_extent(inode, ordered); 9258 btrfs_put_ordered_extent(ordered); 9259 btrfs_put_ordered_extent(ordered); 9260 } 9261 } 9262 btrfs_qgroup_check_reserved_leak(inode); 9263 inode_tree_del(inode); 9264 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0); 9265 free: 9266 call_rcu(&inode->i_rcu, btrfs_i_callback); 9267 } 9268 9269 int btrfs_drop_inode(struct inode *inode) 9270 { 9271 struct btrfs_root *root = BTRFS_I(inode)->root; 9272 9273 if (root == NULL) 9274 return 1; 9275 9276 /* the snap/subvol tree is on deleting */ 9277 if (btrfs_root_refs(&root->root_item) == 0) 9278 return 1; 9279 else 9280 return generic_drop_inode(inode); 9281 } 9282 9283 static void init_once(void *foo) 9284 { 9285 struct btrfs_inode *ei = (struct btrfs_inode *) foo; 9286 9287 inode_init_once(&ei->vfs_inode); 9288 } 9289 9290 void __cold btrfs_destroy_cachep(void) 9291 { 9292 /* 9293 * Make sure all delayed rcu free inodes are flushed before we 9294 * destroy cache. 9295 */ 9296 rcu_barrier(); 9297 kmem_cache_destroy(btrfs_inode_cachep); 9298 kmem_cache_destroy(btrfs_trans_handle_cachep); 9299 kmem_cache_destroy(btrfs_path_cachep); 9300 kmem_cache_destroy(btrfs_free_space_cachep); 9301 } 9302 9303 int __init btrfs_init_cachep(void) 9304 { 9305 btrfs_inode_cachep = kmem_cache_create("btrfs_inode", 9306 sizeof(struct btrfs_inode), 0, 9307 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT, 9308 init_once); 9309 if (!btrfs_inode_cachep) 9310 goto fail; 9311 9312 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle", 9313 sizeof(struct btrfs_trans_handle), 0, 9314 SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL); 9315 if (!btrfs_trans_handle_cachep) 9316 goto fail; 9317 9318 btrfs_path_cachep = kmem_cache_create("btrfs_path", 9319 sizeof(struct btrfs_path), 0, 9320 SLAB_MEM_SPREAD, NULL); 9321 if (!btrfs_path_cachep) 9322 goto fail; 9323 9324 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space", 9325 sizeof(struct btrfs_free_space), 0, 9326 SLAB_MEM_SPREAD, NULL); 9327 if (!btrfs_free_space_cachep) 9328 goto fail; 9329 9330 return 0; 9331 fail: 9332 btrfs_destroy_cachep(); 9333 return -ENOMEM; 9334 } 9335 9336 static int btrfs_getattr(const struct path *path, struct kstat *stat, 9337 u32 request_mask, unsigned int flags) 9338 { 9339 u64 delalloc_bytes; 9340 struct inode *inode = d_inode(path->dentry); 9341 u32 blocksize = inode->i_sb->s_blocksize; 9342 u32 bi_flags = BTRFS_I(inode)->flags; 9343 9344 stat->result_mask |= STATX_BTIME; 9345 stat->btime.tv_sec = BTRFS_I(inode)->i_otime.tv_sec; 9346 stat->btime.tv_nsec = BTRFS_I(inode)->i_otime.tv_nsec; 9347 if (bi_flags & BTRFS_INODE_APPEND) 9348 stat->attributes |= STATX_ATTR_APPEND; 9349 if (bi_flags & BTRFS_INODE_COMPRESS) 9350 stat->attributes |= STATX_ATTR_COMPRESSED; 9351 if (bi_flags & BTRFS_INODE_IMMUTABLE) 9352 stat->attributes |= STATX_ATTR_IMMUTABLE; 9353 if (bi_flags & BTRFS_INODE_NODUMP) 9354 stat->attributes |= STATX_ATTR_NODUMP; 9355 9356 stat->attributes_mask |= (STATX_ATTR_APPEND | 9357 STATX_ATTR_COMPRESSED | 9358 STATX_ATTR_IMMUTABLE | 9359 STATX_ATTR_NODUMP); 9360 9361 generic_fillattr(inode, stat); 9362 stat->dev = BTRFS_I(inode)->root->anon_dev; 9363 9364 spin_lock(&BTRFS_I(inode)->lock); 9365 delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes; 9366 spin_unlock(&BTRFS_I(inode)->lock); 9367 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) + 9368 ALIGN(delalloc_bytes, blocksize)) >> 9; 9369 return 0; 9370 } 9371 9372 static int btrfs_rename_exchange(struct inode *old_dir, 9373 struct dentry *old_dentry, 9374 struct inode *new_dir, 9375 struct dentry *new_dentry) 9376 { 9377 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb); 9378 struct btrfs_trans_handle *trans; 9379 struct btrfs_root *root = BTRFS_I(old_dir)->root; 9380 struct btrfs_root *dest = BTRFS_I(new_dir)->root; 9381 struct inode *new_inode = new_dentry->d_inode; 9382 struct inode *old_inode = old_dentry->d_inode; 9383 struct timespec64 ctime = current_time(old_inode); 9384 struct dentry *parent; 9385 u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); 9386 u64 new_ino = btrfs_ino(BTRFS_I(new_inode)); 9387 u64 old_idx = 0; 9388 u64 new_idx = 0; 9389 u64 root_objectid; 9390 int ret; 9391 int ret2; 9392 bool root_log_pinned = false; 9393 bool dest_log_pinned = false; 9394 9395 /* we only allow rename subvolume link between subvolumes */ 9396 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) 9397 return -EXDEV; 9398 9399 /* close the race window with snapshot create/destroy ioctl */ 9400 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9401 down_read(&fs_info->subvol_sem); 9402 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) 9403 down_read(&fs_info->subvol_sem); 9404 9405 /* 9406 * We want to reserve the absolute worst case amount of items. So if 9407 * both inodes are subvols and we need to unlink them then that would 9408 * require 4 item modifications, but if they are both normal inodes it 9409 * would require 5 item modifications, so we'll assume their normal 9410 * inodes. So 5 * 2 is 10, plus 2 for the new links, so 12 total items 9411 * should cover the worst case number of items we'll modify. 9412 */ 9413 trans = btrfs_start_transaction(root, 12); 9414 if (IS_ERR(trans)) { 9415 ret = PTR_ERR(trans); 9416 goto out_notrans; 9417 } 9418 9419 /* 9420 * We need to find a free sequence number both in the source and 9421 * in the destination directory for the exchange. 9422 */ 9423 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &old_idx); 9424 if (ret) 9425 goto out_fail; 9426 ret = btrfs_set_inode_index(BTRFS_I(old_dir), &new_idx); 9427 if (ret) 9428 goto out_fail; 9429 9430 BTRFS_I(old_inode)->dir_index = 0ULL; 9431 BTRFS_I(new_inode)->dir_index = 0ULL; 9432 9433 /* Reference for the source. */ 9434 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { 9435 /* force full log commit if subvolume involved. */ 9436 btrfs_set_log_full_commit(fs_info, trans); 9437 } else { 9438 btrfs_pin_log_trans(root); 9439 root_log_pinned = true; 9440 ret = btrfs_insert_inode_ref(trans, dest, 9441 new_dentry->d_name.name, 9442 new_dentry->d_name.len, 9443 old_ino, 9444 btrfs_ino(BTRFS_I(new_dir)), 9445 old_idx); 9446 if (ret) 9447 goto out_fail; 9448 } 9449 9450 /* And now for the dest. */ 9451 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { 9452 /* force full log commit if subvolume involved. */ 9453 btrfs_set_log_full_commit(fs_info, trans); 9454 } else { 9455 btrfs_pin_log_trans(dest); 9456 dest_log_pinned = true; 9457 ret = btrfs_insert_inode_ref(trans, root, 9458 old_dentry->d_name.name, 9459 old_dentry->d_name.len, 9460 new_ino, 9461 btrfs_ino(BTRFS_I(old_dir)), 9462 new_idx); 9463 if (ret) 9464 goto out_fail; 9465 } 9466 9467 /* Update inode version and ctime/mtime. */ 9468 inode_inc_iversion(old_dir); 9469 inode_inc_iversion(new_dir); 9470 inode_inc_iversion(old_inode); 9471 inode_inc_iversion(new_inode); 9472 old_dir->i_ctime = old_dir->i_mtime = ctime; 9473 new_dir->i_ctime = new_dir->i_mtime = ctime; 9474 old_inode->i_ctime = ctime; 9475 new_inode->i_ctime = ctime; 9476 9477 if (old_dentry->d_parent != new_dentry->d_parent) { 9478 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), 9479 BTRFS_I(old_inode), 1); 9480 btrfs_record_unlink_dir(trans, BTRFS_I(new_dir), 9481 BTRFS_I(new_inode), 1); 9482 } 9483 9484 /* src is a subvolume */ 9485 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { 9486 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; 9487 ret = btrfs_unlink_subvol(trans, old_dir, root_objectid, 9488 old_dentry->d_name.name, 9489 old_dentry->d_name.len); 9490 } else { /* src is an inode */ 9491 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir), 9492 BTRFS_I(old_dentry->d_inode), 9493 old_dentry->d_name.name, 9494 old_dentry->d_name.len); 9495 if (!ret) 9496 ret = btrfs_update_inode(trans, root, old_inode); 9497 } 9498 if (ret) { 9499 btrfs_abort_transaction(trans, ret); 9500 goto out_fail; 9501 } 9502 9503 /* dest is a subvolume */ 9504 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { 9505 root_objectid = BTRFS_I(new_inode)->root->root_key.objectid; 9506 ret = btrfs_unlink_subvol(trans, new_dir, root_objectid, 9507 new_dentry->d_name.name, 9508 new_dentry->d_name.len); 9509 } else { /* dest is an inode */ 9510 ret = __btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir), 9511 BTRFS_I(new_dentry->d_inode), 9512 new_dentry->d_name.name, 9513 new_dentry->d_name.len); 9514 if (!ret) 9515 ret = btrfs_update_inode(trans, dest, new_inode); 9516 } 9517 if (ret) { 9518 btrfs_abort_transaction(trans, ret); 9519 goto out_fail; 9520 } 9521 9522 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), 9523 new_dentry->d_name.name, 9524 new_dentry->d_name.len, 0, old_idx); 9525 if (ret) { 9526 btrfs_abort_transaction(trans, ret); 9527 goto out_fail; 9528 } 9529 9530 ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode), 9531 old_dentry->d_name.name, 9532 old_dentry->d_name.len, 0, new_idx); 9533 if (ret) { 9534 btrfs_abort_transaction(trans, ret); 9535 goto out_fail; 9536 } 9537 9538 if (old_inode->i_nlink == 1) 9539 BTRFS_I(old_inode)->dir_index = old_idx; 9540 if (new_inode->i_nlink == 1) 9541 BTRFS_I(new_inode)->dir_index = new_idx; 9542 9543 if (root_log_pinned) { 9544 parent = new_dentry->d_parent; 9545 btrfs_log_new_name(trans, BTRFS_I(old_inode), BTRFS_I(old_dir), 9546 parent); 9547 btrfs_end_log_trans(root); 9548 root_log_pinned = false; 9549 } 9550 if (dest_log_pinned) { 9551 parent = old_dentry->d_parent; 9552 btrfs_log_new_name(trans, BTRFS_I(new_inode), BTRFS_I(new_dir), 9553 parent); 9554 btrfs_end_log_trans(dest); 9555 dest_log_pinned = false; 9556 } 9557 out_fail: 9558 /* 9559 * If we have pinned a log and an error happened, we unpin tasks 9560 * trying to sync the log and force them to fallback to a transaction 9561 * commit if the log currently contains any of the inodes involved in 9562 * this rename operation (to ensure we do not persist a log with an 9563 * inconsistent state for any of these inodes or leading to any 9564 * inconsistencies when replayed). If the transaction was aborted, the 9565 * abortion reason is propagated to userspace when attempting to commit 9566 * the transaction. If the log does not contain any of these inodes, we 9567 * allow the tasks to sync it. 9568 */ 9569 if (ret && (root_log_pinned || dest_log_pinned)) { 9570 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) || 9571 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) || 9572 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) || 9573 (new_inode && 9574 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation))) 9575 btrfs_set_log_full_commit(fs_info, trans); 9576 9577 if (root_log_pinned) { 9578 btrfs_end_log_trans(root); 9579 root_log_pinned = false; 9580 } 9581 if (dest_log_pinned) { 9582 btrfs_end_log_trans(dest); 9583 dest_log_pinned = false; 9584 } 9585 } 9586 ret2 = btrfs_end_transaction(trans); 9587 ret = ret ? ret : ret2; 9588 out_notrans: 9589 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) 9590 up_read(&fs_info->subvol_sem); 9591 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9592 up_read(&fs_info->subvol_sem); 9593 9594 return ret; 9595 } 9596 9597 static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans, 9598 struct btrfs_root *root, 9599 struct inode *dir, 9600 struct dentry *dentry) 9601 { 9602 int ret; 9603 struct inode *inode; 9604 u64 objectid; 9605 u64 index; 9606 9607 ret = btrfs_find_free_ino(root, &objectid); 9608 if (ret) 9609 return ret; 9610 9611 inode = btrfs_new_inode(trans, root, dir, 9612 dentry->d_name.name, 9613 dentry->d_name.len, 9614 btrfs_ino(BTRFS_I(dir)), 9615 objectid, 9616 S_IFCHR | WHITEOUT_MODE, 9617 &index); 9618 9619 if (IS_ERR(inode)) { 9620 ret = PTR_ERR(inode); 9621 return ret; 9622 } 9623 9624 inode->i_op = &btrfs_special_inode_operations; 9625 init_special_inode(inode, inode->i_mode, 9626 WHITEOUT_DEV); 9627 9628 ret = btrfs_init_inode_security(trans, inode, dir, 9629 &dentry->d_name); 9630 if (ret) 9631 goto out; 9632 9633 ret = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, 9634 BTRFS_I(inode), 0, index); 9635 if (ret) 9636 goto out; 9637 9638 ret = btrfs_update_inode(trans, root, inode); 9639 out: 9640 unlock_new_inode(inode); 9641 if (ret) 9642 inode_dec_link_count(inode); 9643 iput(inode); 9644 9645 return ret; 9646 } 9647 9648 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, 9649 struct inode *new_dir, struct dentry *new_dentry, 9650 unsigned int flags) 9651 { 9652 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb); 9653 struct btrfs_trans_handle *trans; 9654 unsigned int trans_num_items; 9655 struct btrfs_root *root = BTRFS_I(old_dir)->root; 9656 struct btrfs_root *dest = BTRFS_I(new_dir)->root; 9657 struct inode *new_inode = d_inode(new_dentry); 9658 struct inode *old_inode = d_inode(old_dentry); 9659 u64 index = 0; 9660 u64 root_objectid; 9661 int ret; 9662 u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); 9663 bool log_pinned = false; 9664 9665 if (btrfs_ino(BTRFS_I(new_dir)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) 9666 return -EPERM; 9667 9668 /* we only allow rename subvolume link between subvolumes */ 9669 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) 9670 return -EXDEV; 9671 9672 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || 9673 (new_inode && btrfs_ino(BTRFS_I(new_inode)) == BTRFS_FIRST_FREE_OBJECTID)) 9674 return -ENOTEMPTY; 9675 9676 if (S_ISDIR(old_inode->i_mode) && new_inode && 9677 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) 9678 return -ENOTEMPTY; 9679 9680 9681 /* check for collisions, even if the name isn't there */ 9682 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino, 9683 new_dentry->d_name.name, 9684 new_dentry->d_name.len); 9685 9686 if (ret) { 9687 if (ret == -EEXIST) { 9688 /* we shouldn't get 9689 * eexist without a new_inode */ 9690 if (WARN_ON(!new_inode)) { 9691 return ret; 9692 } 9693 } else { 9694 /* maybe -EOVERFLOW */ 9695 return ret; 9696 } 9697 } 9698 ret = 0; 9699 9700 /* 9701 * we're using rename to replace one file with another. Start IO on it 9702 * now so we don't add too much work to the end of the transaction 9703 */ 9704 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size) 9705 filemap_flush(old_inode->i_mapping); 9706 9707 /* close the racy window with snapshot create/destroy ioctl */ 9708 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9709 down_read(&fs_info->subvol_sem); 9710 /* 9711 * We want to reserve the absolute worst case amount of items. So if 9712 * both inodes are subvols and we need to unlink them then that would 9713 * require 4 item modifications, but if they are both normal inodes it 9714 * would require 5 item modifications, so we'll assume they are normal 9715 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items 9716 * should cover the worst case number of items we'll modify. 9717 * If our rename has the whiteout flag, we need more 5 units for the 9718 * new inode (1 inode item, 1 inode ref, 2 dir items and 1 xattr item 9719 * when selinux is enabled). 9720 */ 9721 trans_num_items = 11; 9722 if (flags & RENAME_WHITEOUT) 9723 trans_num_items += 5; 9724 trans = btrfs_start_transaction(root, trans_num_items); 9725 if (IS_ERR(trans)) { 9726 ret = PTR_ERR(trans); 9727 goto out_notrans; 9728 } 9729 9730 if (dest != root) 9731 btrfs_record_root_in_trans(trans, dest); 9732 9733 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &index); 9734 if (ret) 9735 goto out_fail; 9736 9737 BTRFS_I(old_inode)->dir_index = 0ULL; 9738 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { 9739 /* force full log commit if subvolume involved. */ 9740 btrfs_set_log_full_commit(fs_info, trans); 9741 } else { 9742 btrfs_pin_log_trans(root); 9743 log_pinned = true; 9744 ret = btrfs_insert_inode_ref(trans, dest, 9745 new_dentry->d_name.name, 9746 new_dentry->d_name.len, 9747 old_ino, 9748 btrfs_ino(BTRFS_I(new_dir)), index); 9749 if (ret) 9750 goto out_fail; 9751 } 9752 9753 inode_inc_iversion(old_dir); 9754 inode_inc_iversion(new_dir); 9755 inode_inc_iversion(old_inode); 9756 old_dir->i_ctime = old_dir->i_mtime = 9757 new_dir->i_ctime = new_dir->i_mtime = 9758 old_inode->i_ctime = current_time(old_dir); 9759 9760 if (old_dentry->d_parent != new_dentry->d_parent) 9761 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), 9762 BTRFS_I(old_inode), 1); 9763 9764 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { 9765 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; 9766 ret = btrfs_unlink_subvol(trans, old_dir, root_objectid, 9767 old_dentry->d_name.name, 9768 old_dentry->d_name.len); 9769 } else { 9770 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir), 9771 BTRFS_I(d_inode(old_dentry)), 9772 old_dentry->d_name.name, 9773 old_dentry->d_name.len); 9774 if (!ret) 9775 ret = btrfs_update_inode(trans, root, old_inode); 9776 } 9777 if (ret) { 9778 btrfs_abort_transaction(trans, ret); 9779 goto out_fail; 9780 } 9781 9782 if (new_inode) { 9783 inode_inc_iversion(new_inode); 9784 new_inode->i_ctime = current_time(new_inode); 9785 if (unlikely(btrfs_ino(BTRFS_I(new_inode)) == 9786 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { 9787 root_objectid = BTRFS_I(new_inode)->location.objectid; 9788 ret = btrfs_unlink_subvol(trans, new_dir, root_objectid, 9789 new_dentry->d_name.name, 9790 new_dentry->d_name.len); 9791 BUG_ON(new_inode->i_nlink == 0); 9792 } else { 9793 ret = btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir), 9794 BTRFS_I(d_inode(new_dentry)), 9795 new_dentry->d_name.name, 9796 new_dentry->d_name.len); 9797 } 9798 if (!ret && new_inode->i_nlink == 0) 9799 ret = btrfs_orphan_add(trans, 9800 BTRFS_I(d_inode(new_dentry))); 9801 if (ret) { 9802 btrfs_abort_transaction(trans, ret); 9803 goto out_fail; 9804 } 9805 } 9806 9807 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), 9808 new_dentry->d_name.name, 9809 new_dentry->d_name.len, 0, index); 9810 if (ret) { 9811 btrfs_abort_transaction(trans, ret); 9812 goto out_fail; 9813 } 9814 9815 if (old_inode->i_nlink == 1) 9816 BTRFS_I(old_inode)->dir_index = index; 9817 9818 if (log_pinned) { 9819 struct dentry *parent = new_dentry->d_parent; 9820 9821 btrfs_log_new_name(trans, BTRFS_I(old_inode), BTRFS_I(old_dir), 9822 parent); 9823 btrfs_end_log_trans(root); 9824 log_pinned = false; 9825 } 9826 9827 if (flags & RENAME_WHITEOUT) { 9828 ret = btrfs_whiteout_for_rename(trans, root, old_dir, 9829 old_dentry); 9830 9831 if (ret) { 9832 btrfs_abort_transaction(trans, ret); 9833 goto out_fail; 9834 } 9835 } 9836 out_fail: 9837 /* 9838 * If we have pinned the log and an error happened, we unpin tasks 9839 * trying to sync the log and force them to fallback to a transaction 9840 * commit if the log currently contains any of the inodes involved in 9841 * this rename operation (to ensure we do not persist a log with an 9842 * inconsistent state for any of these inodes or leading to any 9843 * inconsistencies when replayed). If the transaction was aborted, the 9844 * abortion reason is propagated to userspace when attempting to commit 9845 * the transaction. If the log does not contain any of these inodes, we 9846 * allow the tasks to sync it. 9847 */ 9848 if (ret && log_pinned) { 9849 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) || 9850 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) || 9851 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) || 9852 (new_inode && 9853 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation))) 9854 btrfs_set_log_full_commit(fs_info, trans); 9855 9856 btrfs_end_log_trans(root); 9857 log_pinned = false; 9858 } 9859 btrfs_end_transaction(trans); 9860 out_notrans: 9861 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) 9862 up_read(&fs_info->subvol_sem); 9863 9864 return ret; 9865 } 9866 9867 static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry, 9868 struct inode *new_dir, struct dentry *new_dentry, 9869 unsigned int flags) 9870 { 9871 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 9872 return -EINVAL; 9873 9874 if (flags & RENAME_EXCHANGE) 9875 return btrfs_rename_exchange(old_dir, old_dentry, new_dir, 9876 new_dentry); 9877 9878 return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 9879 } 9880 9881 struct btrfs_delalloc_work { 9882 struct inode *inode; 9883 struct completion completion; 9884 struct list_head list; 9885 struct btrfs_work work; 9886 }; 9887 9888 static void btrfs_run_delalloc_work(struct btrfs_work *work) 9889 { 9890 struct btrfs_delalloc_work *delalloc_work; 9891 struct inode *inode; 9892 9893 delalloc_work = container_of(work, struct btrfs_delalloc_work, 9894 work); 9895 inode = delalloc_work->inode; 9896 filemap_flush(inode->i_mapping); 9897 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, 9898 &BTRFS_I(inode)->runtime_flags)) 9899 filemap_flush(inode->i_mapping); 9900 9901 iput(inode); 9902 complete(&delalloc_work->completion); 9903 } 9904 9905 static struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode) 9906 { 9907 struct btrfs_delalloc_work *work; 9908 9909 work = kmalloc(sizeof(*work), GFP_NOFS); 9910 if (!work) 9911 return NULL; 9912 9913 init_completion(&work->completion); 9914 INIT_LIST_HEAD(&work->list); 9915 work->inode = inode; 9916 WARN_ON_ONCE(!inode); 9917 btrfs_init_work(&work->work, btrfs_flush_delalloc_helper, 9918 btrfs_run_delalloc_work, NULL, NULL); 9919 9920 return work; 9921 } 9922 9923 /* 9924 * some fairly slow code that needs optimization. This walks the list 9925 * of all the inodes with pending delalloc and forces them to disk. 9926 */ 9927 static int start_delalloc_inodes(struct btrfs_root *root, int nr) 9928 { 9929 struct btrfs_inode *binode; 9930 struct inode *inode; 9931 struct btrfs_delalloc_work *work, *next; 9932 struct list_head works; 9933 struct list_head splice; 9934 int ret = 0; 9935 9936 INIT_LIST_HEAD(&works); 9937 INIT_LIST_HEAD(&splice); 9938 9939 mutex_lock(&root->delalloc_mutex); 9940 spin_lock(&root->delalloc_lock); 9941 list_splice_init(&root->delalloc_inodes, &splice); 9942 while (!list_empty(&splice)) { 9943 binode = list_entry(splice.next, struct btrfs_inode, 9944 delalloc_inodes); 9945 9946 list_move_tail(&binode->delalloc_inodes, 9947 &root->delalloc_inodes); 9948 inode = igrab(&binode->vfs_inode); 9949 if (!inode) { 9950 cond_resched_lock(&root->delalloc_lock); 9951 continue; 9952 } 9953 spin_unlock(&root->delalloc_lock); 9954 9955 work = btrfs_alloc_delalloc_work(inode); 9956 if (!work) { 9957 iput(inode); 9958 ret = -ENOMEM; 9959 goto out; 9960 } 9961 list_add_tail(&work->list, &works); 9962 btrfs_queue_work(root->fs_info->flush_workers, 9963 &work->work); 9964 ret++; 9965 if (nr != -1 && ret >= nr) 9966 goto out; 9967 cond_resched(); 9968 spin_lock(&root->delalloc_lock); 9969 } 9970 spin_unlock(&root->delalloc_lock); 9971 9972 out: 9973 list_for_each_entry_safe(work, next, &works, list) { 9974 list_del_init(&work->list); 9975 wait_for_completion(&work->completion); 9976 kfree(work); 9977 } 9978 9979 if (!list_empty(&splice)) { 9980 spin_lock(&root->delalloc_lock); 9981 list_splice_tail(&splice, &root->delalloc_inodes); 9982 spin_unlock(&root->delalloc_lock); 9983 } 9984 mutex_unlock(&root->delalloc_mutex); 9985 return ret; 9986 } 9987 9988 int btrfs_start_delalloc_inodes(struct btrfs_root *root) 9989 { 9990 struct btrfs_fs_info *fs_info = root->fs_info; 9991 int ret; 9992 9993 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 9994 return -EROFS; 9995 9996 ret = start_delalloc_inodes(root, -1); 9997 if (ret > 0) 9998 ret = 0; 9999 return ret; 10000 } 10001 10002 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int nr) 10003 { 10004 struct btrfs_root *root; 10005 struct list_head splice; 10006 int ret; 10007 10008 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 10009 return -EROFS; 10010 10011 INIT_LIST_HEAD(&splice); 10012 10013 mutex_lock(&fs_info->delalloc_root_mutex); 10014 spin_lock(&fs_info->delalloc_root_lock); 10015 list_splice_init(&fs_info->delalloc_roots, &splice); 10016 while (!list_empty(&splice) && nr) { 10017 root = list_first_entry(&splice, struct btrfs_root, 10018 delalloc_root); 10019 root = btrfs_grab_fs_root(root); 10020 BUG_ON(!root); 10021 list_move_tail(&root->delalloc_root, 10022 &fs_info->delalloc_roots); 10023 spin_unlock(&fs_info->delalloc_root_lock); 10024 10025 ret = start_delalloc_inodes(root, nr); 10026 btrfs_put_fs_root(root); 10027 if (ret < 0) 10028 goto out; 10029 10030 if (nr != -1) { 10031 nr -= ret; 10032 WARN_ON(nr < 0); 10033 } 10034 spin_lock(&fs_info->delalloc_root_lock); 10035 } 10036 spin_unlock(&fs_info->delalloc_root_lock); 10037 10038 ret = 0; 10039 out: 10040 if (!list_empty(&splice)) { 10041 spin_lock(&fs_info->delalloc_root_lock); 10042 list_splice_tail(&splice, &fs_info->delalloc_roots); 10043 spin_unlock(&fs_info->delalloc_root_lock); 10044 } 10045 mutex_unlock(&fs_info->delalloc_root_mutex); 10046 return ret; 10047 } 10048 10049 static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 10050 const char *symname) 10051 { 10052 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 10053 struct btrfs_trans_handle *trans; 10054 struct btrfs_root *root = BTRFS_I(dir)->root; 10055 struct btrfs_path *path; 10056 struct btrfs_key key; 10057 struct inode *inode = NULL; 10058 int err; 10059 u64 objectid; 10060 u64 index = 0; 10061 int name_len; 10062 int datasize; 10063 unsigned long ptr; 10064 struct btrfs_file_extent_item *ei; 10065 struct extent_buffer *leaf; 10066 10067 name_len = strlen(symname); 10068 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info)) 10069 return -ENAMETOOLONG; 10070 10071 /* 10072 * 2 items for inode item and ref 10073 * 2 items for dir items 10074 * 1 item for updating parent inode item 10075 * 1 item for the inline extent item 10076 * 1 item for xattr if selinux is on 10077 */ 10078 trans = btrfs_start_transaction(root, 7); 10079 if (IS_ERR(trans)) 10080 return PTR_ERR(trans); 10081 10082 err = btrfs_find_free_ino(root, &objectid); 10083 if (err) 10084 goto out_unlock; 10085 10086 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, 10087 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), 10088 objectid, S_IFLNK|S_IRWXUGO, &index); 10089 if (IS_ERR(inode)) { 10090 err = PTR_ERR(inode); 10091 inode = NULL; 10092 goto out_unlock; 10093 } 10094 10095 /* 10096 * If the active LSM wants to access the inode during 10097 * d_instantiate it needs these. Smack checks to see 10098 * if the filesystem supports xattrs by looking at the 10099 * ops vector. 10100 */ 10101 inode->i_fop = &btrfs_file_operations; 10102 inode->i_op = &btrfs_file_inode_operations; 10103 inode->i_mapping->a_ops = &btrfs_aops; 10104 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 10105 10106 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); 10107 if (err) 10108 goto out_unlock; 10109 10110 path = btrfs_alloc_path(); 10111 if (!path) { 10112 err = -ENOMEM; 10113 goto out_unlock; 10114 } 10115 key.objectid = btrfs_ino(BTRFS_I(inode)); 10116 key.offset = 0; 10117 key.type = BTRFS_EXTENT_DATA_KEY; 10118 datasize = btrfs_file_extent_calc_inline_size(name_len); 10119 err = btrfs_insert_empty_item(trans, root, path, &key, 10120 datasize); 10121 if (err) { 10122 btrfs_free_path(path); 10123 goto out_unlock; 10124 } 10125 leaf = path->nodes[0]; 10126 ei = btrfs_item_ptr(leaf, path->slots[0], 10127 struct btrfs_file_extent_item); 10128 btrfs_set_file_extent_generation(leaf, ei, trans->transid); 10129 btrfs_set_file_extent_type(leaf, ei, 10130 BTRFS_FILE_EXTENT_INLINE); 10131 btrfs_set_file_extent_encryption(leaf, ei, 0); 10132 btrfs_set_file_extent_compression(leaf, ei, 0); 10133 btrfs_set_file_extent_other_encoding(leaf, ei, 0); 10134 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); 10135 10136 ptr = btrfs_file_extent_inline_start(ei); 10137 write_extent_buffer(leaf, symname, ptr, name_len); 10138 btrfs_mark_buffer_dirty(leaf); 10139 btrfs_free_path(path); 10140 10141 inode->i_op = &btrfs_symlink_inode_operations; 10142 inode_nohighmem(inode); 10143 inode->i_mapping->a_ops = &btrfs_symlink_aops; 10144 inode_set_bytes(inode, name_len); 10145 btrfs_i_size_write(BTRFS_I(inode), name_len); 10146 err = btrfs_update_inode(trans, root, inode); 10147 /* 10148 * Last step, add directory indexes for our symlink inode. This is the 10149 * last step to avoid extra cleanup of these indexes if an error happens 10150 * elsewhere above. 10151 */ 10152 if (!err) 10153 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, 10154 BTRFS_I(inode), 0, index); 10155 if (err) 10156 goto out_unlock; 10157 10158 d_instantiate_new(dentry, inode); 10159 10160 out_unlock: 10161 btrfs_end_transaction(trans); 10162 if (err && inode) { 10163 inode_dec_link_count(inode); 10164 discard_new_inode(inode); 10165 } 10166 btrfs_btree_balance_dirty(fs_info); 10167 return err; 10168 } 10169 10170 static int __btrfs_prealloc_file_range(struct inode *inode, int mode, 10171 u64 start, u64 num_bytes, u64 min_size, 10172 loff_t actual_len, u64 *alloc_hint, 10173 struct btrfs_trans_handle *trans) 10174 { 10175 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 10176 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 10177 struct extent_map *em; 10178 struct btrfs_root *root = BTRFS_I(inode)->root; 10179 struct btrfs_key ins; 10180 u64 cur_offset = start; 10181 u64 i_size; 10182 u64 cur_bytes; 10183 u64 last_alloc = (u64)-1; 10184 int ret = 0; 10185 bool own_trans = true; 10186 u64 end = start + num_bytes - 1; 10187 10188 if (trans) 10189 own_trans = false; 10190 while (num_bytes > 0) { 10191 if (own_trans) { 10192 trans = btrfs_start_transaction(root, 3); 10193 if (IS_ERR(trans)) { 10194 ret = PTR_ERR(trans); 10195 break; 10196 } 10197 } 10198 10199 cur_bytes = min_t(u64, num_bytes, SZ_256M); 10200 cur_bytes = max(cur_bytes, min_size); 10201 /* 10202 * If we are severely fragmented we could end up with really 10203 * small allocations, so if the allocator is returning small 10204 * chunks lets make its job easier by only searching for those 10205 * sized chunks. 10206 */ 10207 cur_bytes = min(cur_bytes, last_alloc); 10208 ret = btrfs_reserve_extent(root, cur_bytes, cur_bytes, 10209 min_size, 0, *alloc_hint, &ins, 1, 0); 10210 if (ret) { 10211 if (own_trans) 10212 btrfs_end_transaction(trans); 10213 break; 10214 } 10215 btrfs_dec_block_group_reservations(fs_info, ins.objectid); 10216 10217 last_alloc = ins.offset; 10218 ret = insert_reserved_file_extent(trans, inode, 10219 cur_offset, ins.objectid, 10220 ins.offset, ins.offset, 10221 ins.offset, 0, 0, 0, 10222 BTRFS_FILE_EXTENT_PREALLOC); 10223 if (ret) { 10224 btrfs_free_reserved_extent(fs_info, ins.objectid, 10225 ins.offset, 0); 10226 btrfs_abort_transaction(trans, ret); 10227 if (own_trans) 10228 btrfs_end_transaction(trans); 10229 break; 10230 } 10231 10232 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, 10233 cur_offset + ins.offset -1, 0); 10234 10235 em = alloc_extent_map(); 10236 if (!em) { 10237 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, 10238 &BTRFS_I(inode)->runtime_flags); 10239 goto next; 10240 } 10241 10242 em->start = cur_offset; 10243 em->orig_start = cur_offset; 10244 em->len = ins.offset; 10245 em->block_start = ins.objectid; 10246 em->block_len = ins.offset; 10247 em->orig_block_len = ins.offset; 10248 em->ram_bytes = ins.offset; 10249 em->bdev = fs_info->fs_devices->latest_bdev; 10250 set_bit(EXTENT_FLAG_PREALLOC, &em->flags); 10251 em->generation = trans->transid; 10252 10253 while (1) { 10254 write_lock(&em_tree->lock); 10255 ret = add_extent_mapping(em_tree, em, 1); 10256 write_unlock(&em_tree->lock); 10257 if (ret != -EEXIST) 10258 break; 10259 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset, 10260 cur_offset + ins.offset - 1, 10261 0); 10262 } 10263 free_extent_map(em); 10264 next: 10265 num_bytes -= ins.offset; 10266 cur_offset += ins.offset; 10267 *alloc_hint = ins.objectid + ins.offset; 10268 10269 inode_inc_iversion(inode); 10270 inode->i_ctime = current_time(inode); 10271 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC; 10272 if (!(mode & FALLOC_FL_KEEP_SIZE) && 10273 (actual_len > inode->i_size) && 10274 (cur_offset > inode->i_size)) { 10275 if (cur_offset > actual_len) 10276 i_size = actual_len; 10277 else 10278 i_size = cur_offset; 10279 i_size_write(inode, i_size); 10280 btrfs_ordered_update_i_size(inode, i_size, NULL); 10281 } 10282 10283 ret = btrfs_update_inode(trans, root, inode); 10284 10285 if (ret) { 10286 btrfs_abort_transaction(trans, ret); 10287 if (own_trans) 10288 btrfs_end_transaction(trans); 10289 break; 10290 } 10291 10292 if (own_trans) 10293 btrfs_end_transaction(trans); 10294 } 10295 if (cur_offset < end) 10296 btrfs_free_reserved_data_space(inode, NULL, cur_offset, 10297 end - cur_offset + 1); 10298 return ret; 10299 } 10300 10301 int btrfs_prealloc_file_range(struct inode *inode, int mode, 10302 u64 start, u64 num_bytes, u64 min_size, 10303 loff_t actual_len, u64 *alloc_hint) 10304 { 10305 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, 10306 min_size, actual_len, alloc_hint, 10307 NULL); 10308 } 10309 10310 int btrfs_prealloc_file_range_trans(struct inode *inode, 10311 struct btrfs_trans_handle *trans, int mode, 10312 u64 start, u64 num_bytes, u64 min_size, 10313 loff_t actual_len, u64 *alloc_hint) 10314 { 10315 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, 10316 min_size, actual_len, alloc_hint, trans); 10317 } 10318 10319 static int btrfs_set_page_dirty(struct page *page) 10320 { 10321 return __set_page_dirty_nobuffers(page); 10322 } 10323 10324 static int btrfs_permission(struct inode *inode, int mask) 10325 { 10326 struct btrfs_root *root = BTRFS_I(inode)->root; 10327 umode_t mode = inode->i_mode; 10328 10329 if (mask & MAY_WRITE && 10330 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) { 10331 if (btrfs_root_readonly(root)) 10332 return -EROFS; 10333 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) 10334 return -EACCES; 10335 } 10336 return generic_permission(inode, mask); 10337 } 10338 10339 static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 10340 { 10341 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); 10342 struct btrfs_trans_handle *trans; 10343 struct btrfs_root *root = BTRFS_I(dir)->root; 10344 struct inode *inode = NULL; 10345 u64 objectid; 10346 u64 index; 10347 int ret = 0; 10348 10349 /* 10350 * 5 units required for adding orphan entry 10351 */ 10352 trans = btrfs_start_transaction(root, 5); 10353 if (IS_ERR(trans)) 10354 return PTR_ERR(trans); 10355 10356 ret = btrfs_find_free_ino(root, &objectid); 10357 if (ret) 10358 goto out; 10359 10360 inode = btrfs_new_inode(trans, root, dir, NULL, 0, 10361 btrfs_ino(BTRFS_I(dir)), objectid, mode, &index); 10362 if (IS_ERR(inode)) { 10363 ret = PTR_ERR(inode); 10364 inode = NULL; 10365 goto out; 10366 } 10367 10368 inode->i_fop = &btrfs_file_operations; 10369 inode->i_op = &btrfs_file_inode_operations; 10370 10371 inode->i_mapping->a_ops = &btrfs_aops; 10372 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; 10373 10374 ret = btrfs_init_inode_security(trans, inode, dir, NULL); 10375 if (ret) 10376 goto out; 10377 10378 ret = btrfs_update_inode(trans, root, inode); 10379 if (ret) 10380 goto out; 10381 ret = btrfs_orphan_add(trans, BTRFS_I(inode)); 10382 if (ret) 10383 goto out; 10384 10385 /* 10386 * We set number of links to 0 in btrfs_new_inode(), and here we set 10387 * it to 1 because d_tmpfile() will issue a warning if the count is 0, 10388 * through: 10389 * 10390 * d_tmpfile() -> inode_dec_link_count() -> drop_nlink() 10391 */ 10392 set_nlink(inode, 1); 10393 d_tmpfile(dentry, inode); 10394 unlock_new_inode(inode); 10395 mark_inode_dirty(inode); 10396 out: 10397 btrfs_end_transaction(trans); 10398 if (ret && inode) 10399 discard_new_inode(inode); 10400 btrfs_btree_balance_dirty(fs_info); 10401 return ret; 10402 } 10403 10404 __attribute__((const)) 10405 static int btrfs_readpage_io_failed_hook(struct page *page, int failed_mirror) 10406 { 10407 return -EAGAIN; 10408 } 10409 10410 static void btrfs_check_extent_io_range(void *private_data, const char *caller, 10411 u64 start, u64 end) 10412 { 10413 struct inode *inode = private_data; 10414 u64 isize; 10415 10416 isize = i_size_read(inode); 10417 if (end >= PAGE_SIZE && (end % 2) == 0 && end != isize - 1) { 10418 btrfs_debug_rl(BTRFS_I(inode)->root->fs_info, 10419 "%s: ino %llu isize %llu odd range [%llu,%llu]", 10420 caller, btrfs_ino(BTRFS_I(inode)), isize, start, end); 10421 } 10422 } 10423 10424 void btrfs_set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) 10425 { 10426 struct inode *inode = tree->private_data; 10427 unsigned long index = start >> PAGE_SHIFT; 10428 unsigned long end_index = end >> PAGE_SHIFT; 10429 struct page *page; 10430 10431 while (index <= end_index) { 10432 page = find_get_page(inode->i_mapping, index); 10433 ASSERT(page); /* Pages should be in the extent_io_tree */ 10434 set_page_writeback(page); 10435 put_page(page); 10436 index++; 10437 } 10438 } 10439 10440 static const struct inode_operations btrfs_dir_inode_operations = { 10441 .getattr = btrfs_getattr, 10442 .lookup = btrfs_lookup, 10443 .create = btrfs_create, 10444 .unlink = btrfs_unlink, 10445 .link = btrfs_link, 10446 .mkdir = btrfs_mkdir, 10447 .rmdir = btrfs_rmdir, 10448 .rename = btrfs_rename2, 10449 .symlink = btrfs_symlink, 10450 .setattr = btrfs_setattr, 10451 .mknod = btrfs_mknod, 10452 .listxattr = btrfs_listxattr, 10453 .permission = btrfs_permission, 10454 .get_acl = btrfs_get_acl, 10455 .set_acl = btrfs_set_acl, 10456 .update_time = btrfs_update_time, 10457 .tmpfile = btrfs_tmpfile, 10458 }; 10459 static const struct inode_operations btrfs_dir_ro_inode_operations = { 10460 .lookup = btrfs_lookup, 10461 .permission = btrfs_permission, 10462 .update_time = btrfs_update_time, 10463 }; 10464 10465 static const struct file_operations btrfs_dir_file_operations = { 10466 .llseek = generic_file_llseek, 10467 .read = generic_read_dir, 10468 .iterate_shared = btrfs_real_readdir, 10469 .open = btrfs_opendir, 10470 .unlocked_ioctl = btrfs_ioctl, 10471 #ifdef CONFIG_COMPAT 10472 .compat_ioctl = btrfs_compat_ioctl, 10473 #endif 10474 .release = btrfs_release_file, 10475 .fsync = btrfs_sync_file, 10476 }; 10477 10478 static const struct extent_io_ops btrfs_extent_io_ops = { 10479 /* mandatory callbacks */ 10480 .submit_bio_hook = btrfs_submit_bio_hook, 10481 .readpage_end_io_hook = btrfs_readpage_end_io_hook, 10482 .readpage_io_failed_hook = btrfs_readpage_io_failed_hook, 10483 10484 /* optional callbacks */ 10485 .fill_delalloc = run_delalloc_range, 10486 .writepage_end_io_hook = btrfs_writepage_end_io_hook, 10487 .writepage_start_hook = btrfs_writepage_start_hook, 10488 .set_bit_hook = btrfs_set_bit_hook, 10489 .clear_bit_hook = btrfs_clear_bit_hook, 10490 .merge_extent_hook = btrfs_merge_extent_hook, 10491 .split_extent_hook = btrfs_split_extent_hook, 10492 .check_extent_io_range = btrfs_check_extent_io_range, 10493 }; 10494 10495 /* 10496 * btrfs doesn't support the bmap operation because swapfiles 10497 * use bmap to make a mapping of extents in the file. They assume 10498 * these extents won't change over the life of the file and they 10499 * use the bmap result to do IO directly to the drive. 10500 * 10501 * the btrfs bmap call would return logical addresses that aren't 10502 * suitable for IO and they also will change frequently as COW 10503 * operations happen. So, swapfile + btrfs == corruption. 10504 * 10505 * For now we're avoiding this by dropping bmap. 10506 */ 10507 static const struct address_space_operations btrfs_aops = { 10508 .readpage = btrfs_readpage, 10509 .writepage = btrfs_writepage, 10510 .writepages = btrfs_writepages, 10511 .readpages = btrfs_readpages, 10512 .direct_IO = btrfs_direct_IO, 10513 .invalidatepage = btrfs_invalidatepage, 10514 .releasepage = btrfs_releasepage, 10515 .set_page_dirty = btrfs_set_page_dirty, 10516 .error_remove_page = generic_error_remove_page, 10517 }; 10518 10519 static const struct address_space_operations btrfs_symlink_aops = { 10520 .readpage = btrfs_readpage, 10521 .writepage = btrfs_writepage, 10522 .invalidatepage = btrfs_invalidatepage, 10523 .releasepage = btrfs_releasepage, 10524 }; 10525 10526 static const struct inode_operations btrfs_file_inode_operations = { 10527 .getattr = btrfs_getattr, 10528 .setattr = btrfs_setattr, 10529 .listxattr = btrfs_listxattr, 10530 .permission = btrfs_permission, 10531 .fiemap = btrfs_fiemap, 10532 .get_acl = btrfs_get_acl, 10533 .set_acl = btrfs_set_acl, 10534 .update_time = btrfs_update_time, 10535 }; 10536 static const struct inode_operations btrfs_special_inode_operations = { 10537 .getattr = btrfs_getattr, 10538 .setattr = btrfs_setattr, 10539 .permission = btrfs_permission, 10540 .listxattr = btrfs_listxattr, 10541 .get_acl = btrfs_get_acl, 10542 .set_acl = btrfs_set_acl, 10543 .update_time = btrfs_update_time, 10544 }; 10545 static const struct inode_operations btrfs_symlink_inode_operations = { 10546 .get_link = page_get_link, 10547 .getattr = btrfs_getattr, 10548 .setattr = btrfs_setattr, 10549 .permission = btrfs_permission, 10550 .listxattr = btrfs_listxattr, 10551 .update_time = btrfs_update_time, 10552 }; 10553 10554 const struct dentry_operations btrfs_dentry_operations = { 10555 .d_delete = btrfs_dentry_delete, 10556 }; 10557