Message ID | 044a1ae92ce797c5c9be5ab43359ec820ed151fd.1736759698.git.wqu@suse.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | btrfs: move ordered extents cleanup to where they got allocated | expand |
On Mon, Jan 13, 2025 at 08:12:12PM +1030, Qu Wenruo wrote: > 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 do 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> > --- > fs/btrfs/inode.c | 130 +++++++++++++++++++++++++---------------------- > 1 file changed, 69 insertions(+), 61 deletions(-) > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index 130f0490b14f..42f67f8a4a33 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -1974,6 +1974,71 @@ 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)) > + /* > + * 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, 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. > @@ -2018,15 +2083,12 @@ 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); > @@ -2160,67 +2222,13 @@ 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); > > -- > 2.47.1 >
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 130f0490b14f..42f67f8a4a33 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1974,6 +1974,71 @@ 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)) + /* + * 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, 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. @@ -2018,15 +2083,12 @@ 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); @@ -2160,67 +2222,13 @@ 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);
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 do 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. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/inode.c | 130 +++++++++++++++++++++++++---------------------- 1 file changed, 69 insertions(+), 61 deletions(-)