Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4d53dddb authored by David Sterba's avatar David Sterba
Browse files

btrfs: document existence of extent_io ops callbacks 



Some of the callbacks defined in btree_extent_io_ops and
btrfs_extent_io_ops do always exist so we don't need to check the
existence before each call. This patch just reorders the definition and
documents which are mandatory/optional.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent c3988d63

fs/btrfs/disk-io.c

+5 −2
Original line number Diff line number Diff line
@@ -4653,9 +4653,12 @@ static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info) 
}



static const struct extent_io_ops btree_extent_io_ops = {

	.readpage_end_io_hook = btree_readpage_end_io_hook,

	.readpage_io_failed_hook = btree_io_failed_hook,

	/* mandatory callbacks */

	.submit_bio_hook = btree_submit_bio_hook,

	.readpage_end_io_hook = btree_readpage_end_io_hook,

	/* note we're sharing with inode.c for the merge bio hook */

	.merge_bio_hook = btrfs_merge_bio_hook,



	/* optional callbacks */

	.readpage_io_failed_hook = btree_io_failed_hook,

};

fs/btrfs/extent_io.h

+16 −7
Original line number Diff line number Diff line
@@ -92,18 +92,27 @@ typedef int (extent_submit_bio_hook_t)(struct inode *inode, struct bio *bio, 
				       int mirror_num, unsigned long bio_flags,

				       u64 bio_offset);

struct extent_io_ops {

	int (*fill_delalloc)(struct inode *inode, struct page *locked_page,

			     u64 start, u64 end, int *page_started,

			     unsigned long *nr_written);

	int (*writepage_start_hook)(struct page *page, u64 start, u64 end);

	/*

	 * The following callbacks must be allways defined, the function

	 * pointer will be called unconditionally.

	 */

	extent_submit_bio_hook_t *submit_bio_hook;

	int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,

				    struct page *page, u64 start, u64 end,

				    int mirror);

	int (*merge_bio_hook)(struct page *page, unsigned long offset,

			      size_t size, struct bio *bio,

			      unsigned long bio_flags);



	/*

	 * Optional hooks, called if the pointer is not NULL

	 */

	int (*fill_delalloc)(struct inode *inode, struct page *locked_page,

			     u64 start, u64 end, int *page_started,

			     unsigned long *nr_written);

	int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);

	int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,

				    struct page *page, u64 start, u64 end,

				    int mirror);



	int (*writepage_start_hook)(struct page *page, u64 start, u64 end);

	void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,

				      struct extent_state *state, int uptodate);

	void (*set_bit_hook)(struct inode *inode, struct extent_state *state,

fs/btrfs/inode.c

+5 −2
Original line number Diff line number Diff line
@@ -10547,10 +10547,13 @@ static const struct file_operations btrfs_dir_file_operations = { 
};



static const struct extent_io_ops btrfs_extent_io_ops = {

	.fill_delalloc = run_delalloc_range,

	/* mandatory callbacks */

	.submit_bio_hook = btrfs_submit_bio_hook,

	.merge_bio_hook = btrfs_merge_bio_hook,

	.readpage_end_io_hook = btrfs_readpage_end_io_hook,

	.merge_bio_hook = btrfs_merge_bio_hook,



	/* optional callbacks */

	.fill_delalloc = run_delalloc_range,

	.writepage_end_io_hook = btrfs_writepage_end_io_hook,

	.writepage_start_hook = btrfs_writepage_start_hook,

	.set_bit_hook = btrfs_set_bit_hook,