Commit ec63b84d authored by Christoph Hellwig's avatar Christoph Hellwig Committed by David Sterba
Browse files

btrfs: add an ordered_extent pointer to struct btrfs_bio 



Add a pointer to the ordered_extent to the existing union in struct
btrfs_bio, so all code dealing with data write bios can just use a
pointer dereference to retrieve the ordered_extent instead of doing
multiple rbtree lookups per I/O.

The reference to this ordered_extent is dropped at end I/O time,
which implies that an extra one must be acquired when the bio is split.
This also requires moving the btrfs_extract_ordered_extent call into
btrfs_split_bio so that the invariant of always having a valid
ordered_extent reference for the btrfs_bio is kept.

Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 112397ac

fs/btrfs/bio.c

+38 −4
Original line number Diff line number Diff line
@@ -33,6 +33,11 @@ static inline bool is_data_bbio(struct btrfs_bio *bbio) 
	return bbio->inode && is_data_inode(&bbio->inode->vfs_inode);

}



static bool bbio_has_ordered_extent(struct btrfs_bio *bbio)

{

	return is_data_bbio(bbio) && btrfs_op(&bbio->bio) == BTRFS_MAP_WRITE;

}



/*

 * Initialize a btrfs_bio structure.  This skips the embedded bio itself as it

 * is already initialized by the block layer.
@@ -88,11 +93,40 @@ static struct btrfs_bio *btrfs_split_bio(struct btrfs_fs_info *fs_info, 
	bbio->inode = orig_bbio->inode;

	bbio->file_offset = orig_bbio->file_offset;

	orig_bbio->file_offset += map_length;



	if (bbio_has_ordered_extent(bbio)) {

		refcount_inc(&orig_bbio->ordered->refs);

		bbio->ordered = orig_bbio->ordered;

	}

	atomic_inc(&orig_bbio->pending_ios);

	return bbio;

}



/* Free a bio that was never submitted to the underlying device. */

static void btrfs_cleanup_bio(struct btrfs_bio *bbio)

{

	if (bbio_has_ordered_extent(bbio))

		btrfs_put_ordered_extent(bbio->ordered);

	bio_put(&bbio->bio);

}



static void __btrfs_bio_end_io(struct btrfs_bio *bbio)

{

	if (bbio_has_ordered_extent(bbio)) {

		struct btrfs_ordered_extent *ordered = bbio->ordered;



		bbio->end_io(bbio);

		btrfs_put_ordered_extent(ordered);

	} else {

		bbio->end_io(bbio);

	}

}



void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status)

{

	bbio->bio.bi_status = status;

	__btrfs_bio_end_io(bbio);

}



static void btrfs_orig_write_end_io(struct bio *bio);



static void btrfs_bbio_propagate_error(struct btrfs_bio *bbio,
@@ -121,12 +155,12 @@ static void btrfs_orig_bbio_end_io(struct btrfs_bio *bbio) 


		if (bbio->bio.bi_status)

			btrfs_bbio_propagate_error(bbio, orig_bbio);

		bio_put(&bbio->bio);

		btrfs_cleanup_bio(bbio);

		bbio = orig_bbio;

	}



	if (atomic_dec_and_test(&bbio->pending_ios))

		bbio->end_io(bbio);

		__btrfs_bio_end_io(bbio);

}



static int next_repair_mirror(struct btrfs_failed_bio *fbio, int cur_mirror)
@@ -684,7 +718,7 @@ static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num) 


fail_put_bio:

	if (map_length < length)

		bio_put(bio);

		btrfs_cleanup_bio(bbio);

fail:

	btrfs_bio_counter_dec(fs_info);

	btrfs_bio_end_io(orig_bbio, ret);

fs/btrfs/bio.h

+3 −6
Original line number Diff line number Diff line
@@ -50,11 +50,13 @@ struct btrfs_bio { 


		/*

		 * For data writes:

		 * - ordered extent covering the bio

		 * - pointer to the checksums for this bio

		 * - original physical address from the allocator

		 *   (for zone append only)

		 */

		struct {

			struct btrfs_ordered_extent *ordered;

			struct btrfs_ordered_sum *sums;

			u64 orig_physical;

		};
@@ -95,12 +97,7 @@ void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info, 
struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,

				  struct btrfs_fs_info *fs_info,

				  btrfs_bio_end_io_t end_io, void *private);



static inline void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status)

{

	bbio->bio.bi_status = status;

	bbio->end_io(bbio);

}

void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status);



/* Submit using blkcg_punt_bio_submit. */

#define REQ_BTRFS_CGROUP_PUNT			REQ_FS_PRIVATE

fs/btrfs/compression.c

+1 −1
Original line number Diff line number Diff line
@@ -303,10 +303,10 @@ void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered, 
	INIT_WORK(&cb->write_end_work, btrfs_finish_compressed_write_work);

	cb->nr_pages = nr_pages;

	cb->bbio.bio.bi_iter.bi_sector = ordered->disk_bytenr >> SECTOR_SHIFT;

	cb->bbio.ordered = ordered;

	btrfs_add_compressed_bio_pages(cb);



	btrfs_submit_bio(&cb->bbio, 0);

	btrfs_put_ordered_extent(ordered);

}



/*

fs/btrfs/extent_io.c

+1 −1
Original line number Diff line number Diff line
@@ -835,7 +835,7 @@ static void alloc_new_bio(struct btrfs_inode *inode, 
			bio_ctrl->len_to_oe_boundary = min_t(u32, U32_MAX,

					ordered->file_offset +

					ordered->disk_num_bytes - file_offset);

			btrfs_put_ordered_extent(ordered);

			bbio->ordered = ordered;

		}



		/*

fs/btrfs/file-item.c

+1 −8
Original line number Diff line number Diff line
@@ -799,19 +799,12 @@ blk_status_t btrfs_csum_one_bio(struct btrfs_bio *bbio) 
 */

blk_status_t btrfs_alloc_dummy_sum(struct btrfs_bio *bbio)

{

	struct btrfs_ordered_extent *ordered =

		btrfs_lookup_ordered_extent(bbio->inode, bbio->file_offset);



	if (WARN_ON_ONCE(!ordered))

		return BLK_STS_IOERR;



	bbio->sums = kmalloc(sizeof(*bbio->sums), GFP_NOFS);

	if (!bbio->sums)

		return BLK_STS_RESOURCE;

	bbio->sums->len = bbio->bio.bi_iter.bi_size;

	bbio->sums->logical = bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT;

	btrfs_add_ordered_sum(ordered, bbio->sums);

	btrfs_put_ordered_extent(ordered);

	btrfs_add_ordered_sum(bbio->ordered, bbio->sums);

	return 0;

}