6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Qu Wenruo wqu@suse.com
[ Upstream commit 10326fdcb3ace2f2dcbc8b9fc50b87e5cab93345 ]
Currently we're doing all the ordered extent and extent map generation inside a while() loop of run_delalloc_nocow(). This makes it pretty hard to read, nor doing proper error handling.
So move that part of code into a helper, nocow_one_range().
This should not change anything, but there is a tiny timing change where btrfs_dec_nocow_writers() is only called after nocow_one_range() helper exits.
This timing change is small, and makes error handling easier, thus should be fine.
Reviewed-by: Boris Burkov boris@bur.io Signed-off-by: Qu Wenruo wqu@suse.com Signed-off-by: David Sterba dsterba@suse.com Stable-dep-of: 1f2889f5594a ("btrfs: fix qgroup reservation leak on failure to allocate ordered extent") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/inode.c | 122 +++++++++++++++++++++++------------------------ 1 file changed, 61 insertions(+), 61 deletions(-)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 1ab5b0c1b9b76..65517efd3433e 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2055,6 +2055,63 @@ static void cleanup_dirty_folios(struct btrfs_inode *inode, mapping_set_error(mapping, error); }
+static int nocow_one_range(struct btrfs_inode *inode, struct folio *locked_folio, + struct extent_state **cached, + struct can_nocow_file_extent_args *nocow_args, + u64 file_pos, bool is_prealloc) +{ + struct btrfs_ordered_extent *ordered; + u64 len = nocow_args->file_extent.num_bytes; + u64 end = file_pos + len - 1; + int ret = 0; + + lock_extent(&inode->io_tree, file_pos, end, cached); + + if (is_prealloc) { + struct extent_map *em; + + em = btrfs_create_io_em(inode, file_pos, &nocow_args->file_extent, + BTRFS_ORDERED_PREALLOC); + if (IS_ERR(em)) { + unlock_extent(&inode->io_tree, file_pos, end, cached); + return PTR_ERR(em); + } + free_extent_map(em); + } + + ordered = btrfs_alloc_ordered_extent(inode, file_pos, &nocow_args->file_extent, + is_prealloc + ? (1 << BTRFS_ORDERED_PREALLOC) + : (1 << BTRFS_ORDERED_NOCOW)); + if (IS_ERR(ordered)) { + if (is_prealloc) + btrfs_drop_extent_map_range(inode, file_pos, end, false); + unlock_extent(&inode->io_tree, file_pos, end, cached); + return PTR_ERR(ordered); + } + + if (btrfs_is_data_reloc_root(inode->root)) + /* + * Errors are handled later, as we must prevent + * extent_clear_unlock_delalloc() in error handler from freeing + * metadata of the created ordered extent. + */ + ret = btrfs_reloc_clone_csums(ordered); + btrfs_put_ordered_extent(ordered); + + extent_clear_unlock_delalloc(inode, file_pos, end, locked_folio, cached, + EXTENT_LOCKED | EXTENT_DELALLOC | + EXTENT_CLEAR_DATA_RESV, + PAGE_UNLOCK | PAGE_SET_ORDERED); + + /* + * btrfs_reloc_clone_csums() error, now we're OK to call error handler, + * as metadata for created ordered extent will only be freed by + * btrfs_finish_ordered_io(). + */ + return ret; +} + /* * when nowcow writeback call back. This checks for snapshots or COW copies * of the extents that exist in the file, and COWs the file as required. @@ -2099,15 +2156,12 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode,
while (cur_offset <= end) { struct btrfs_block_group *nocow_bg = NULL; - struct btrfs_ordered_extent *ordered; struct btrfs_key found_key; struct btrfs_file_extent_item *fi; struct extent_buffer *leaf; struct extent_state *cached_state = NULL; u64 extent_end; - u64 nocow_end; int extent_type; - bool is_prealloc;
ret = btrfs_lookup_file_extent(NULL, root, path, ino, cur_offset, 0); @@ -2242,67 +2296,13 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode, } }
- nocow_end = cur_offset + nocow_args.file_extent.num_bytes - 1; - lock_extent(&inode->io_tree, cur_offset, nocow_end, &cached_state); - - is_prealloc = extent_type == BTRFS_FILE_EXTENT_PREALLOC; - if (is_prealloc) { - struct extent_map *em; - - em = btrfs_create_io_em(inode, cur_offset, - &nocow_args.file_extent, - BTRFS_ORDERED_PREALLOC); - if (IS_ERR(em)) { - unlock_extent(&inode->io_tree, cur_offset, - nocow_end, &cached_state); - btrfs_dec_nocow_writers(nocow_bg); - ret = PTR_ERR(em); - goto error; - } - free_extent_map(em); - } - - ordered = btrfs_alloc_ordered_extent(inode, cur_offset, - &nocow_args.file_extent, - is_prealloc - ? (1 << BTRFS_ORDERED_PREALLOC) - : (1 << BTRFS_ORDERED_NOCOW)); + ret = nocow_one_range(inode, locked_folio, &cached_state, + &nocow_args, cur_offset, + extent_type == BTRFS_FILE_EXTENT_PREALLOC); btrfs_dec_nocow_writers(nocow_bg); - if (IS_ERR(ordered)) { - if (is_prealloc) { - btrfs_drop_extent_map_range(inode, cur_offset, - nocow_end, false); - } - unlock_extent(&inode->io_tree, cur_offset, - nocow_end, &cached_state); - ret = PTR_ERR(ordered); + if (ret < 0) goto error; - } - - if (btrfs_is_data_reloc_root(root)) - /* - * Error handled later, as we must prevent - * extent_clear_unlock_delalloc() in error handler - * from freeing metadata of created ordered extent. - */ - ret = btrfs_reloc_clone_csums(ordered); - btrfs_put_ordered_extent(ordered); - - extent_clear_unlock_delalloc(inode, cur_offset, nocow_end, - locked_folio, &cached_state, - EXTENT_LOCKED | EXTENT_DELALLOC | - EXTENT_CLEAR_DATA_RESV, - PAGE_UNLOCK | PAGE_SET_ORDERED); - cur_offset = extent_end; - - /* - * btrfs_reloc_clone_csums() error, now we're OK to call error - * handler, as metadata for created ordered extent will only - * be freed by btrfs_finish_ordered_io(). - */ - if (ret) - goto error; } btrfs_release_path(path);