diff options
Diffstat (limited to 'fs/btrfs/inode.c')
| -rw-r--r-- | fs/btrfs/inode.c | 36 |
1 files changed, 26 insertions, 10 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c425443c31fe..dfc0b3adf57a 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -947,7 +947,7 @@ static noinline int cow_file_range(struct inode *inode, u64 alloc_hint = 0; u64 num_bytes; unsigned long ram_size; - u64 disk_num_bytes; + u64 min_alloc_size; u64 cur_alloc_size; u64 blocksize = root->sectorsize; struct btrfs_key ins; @@ -963,7 +963,6 @@ static noinline int cow_file_range(struct inode *inode, num_bytes = ALIGN(end - start + 1, blocksize); num_bytes = max(blocksize, num_bytes); - disk_num_bytes = num_bytes; /* if this is a small write inside eof, kick off defrag */ if (num_bytes < SZ_64K && @@ -992,18 +991,33 @@ static noinline int cow_file_range(struct inode *inode, } } - BUG_ON(disk_num_bytes > - btrfs_super_total_bytes(root->fs_info->super_copy)); + BUG_ON(num_bytes > btrfs_super_total_bytes(root->fs_info->super_copy)); alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); - while (disk_num_bytes > 0) { + /* + * Relocation relies on the relocated extents to have exactly the same + * size as the original extents. Normally writeback for relocation data + * extents follows a NOCOW path because relocation preallocates the + * extents. However, due to an operation such as scrub turning a block + * group to RO mode, it may fallback to COW mode, so we must make sure + * an extent allocated during COW has exactly the requested size and can + * not be split into smaller extents, otherwise relocation breaks and + * fails during the stage where it updates the bytenr of file extent + * items. + */ + if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) + min_alloc_size = num_bytes; + else + min_alloc_size = root->sectorsize; + + while (num_bytes > 0) { unsigned long op; - cur_alloc_size = disk_num_bytes; + cur_alloc_size = num_bytes; ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size, - root->sectorsize, 0, alloc_hint, + min_alloc_size, 0, alloc_hint, &ins, 1, 1); if (ret < 0) goto out_unlock; @@ -1058,7 +1072,7 @@ static noinline int cow_file_range(struct inode *inode, btrfs_dec_block_group_reservations(root->fs_info, ins.objectid); - if (disk_num_bytes < cur_alloc_size) + if (num_bytes < cur_alloc_size) break; /* we're not doing compressed IO, don't unlock the first @@ -1076,8 +1090,10 @@ static noinline int cow_file_range(struct inode *inode, delalloc_end, locked_page, EXTENT_LOCKED | EXTENT_DELALLOC, op); - disk_num_bytes -= cur_alloc_size; - num_bytes -= cur_alloc_size; + if (num_bytes < cur_alloc_size) + num_bytes = 0; + else + num_bytes -= cur_alloc_size; alloc_hint = ins.objectid + ins.offset; start += cur_alloc_size; } |