[PATCH v2] btrfs: Record btrfs_device directly btrfs_io_bio

Nikolay Borisov
2020-07-03T08:14:31Z

Instead of recording stripe_index and using that to access correct
btrfs_device from btrfs_bio::stripes record the btrfs_device in
btrfs_io_bio. This will enable endio handlers to increment device
error counters on checksum errors.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
---

V2: Pass btrfs_device directly to submit_stripe_bio

fs/btrfs/raid56.c | 1 +
fs/btrfs/volumes.c | 14 ++++----------
fs/btrfs/volumes.h | 2 +-
3 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index c870ef70f817..4efd9ed1a30e 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1117,6 +1117,7 @@ static int rbio_add_io_page(struct btrfs_raid_bio *rbio,

/* put a new bio on the list */
bio = btrfs_io_bio_alloc(bio_max_len >> PAGE_SHIFT ?: 1);
+ btrfs_io_bio(bio)->dev = stripe->dev;
bio->bi_iter.bi_size = 0;
bio_set_dev(bio, stripe->dev->bdev);
bio->bi_iter.bi_sector = disk_start >> 9;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index aabc6c922e04..074256c0cba2 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6261,12 +6261,7 @@ static void btrfs_end_bio(struct bio *bio)
atomic_inc(&bbio->error);
if (bio->bi_status == BLK_STS_IOERR ||
bio->bi_status == BLK_STS_TARGET) {
- unsigned int stripe_index =
- btrfs_io_bio(bio)->stripe_index;
- struct btrfs_device *dev;
-
- BUG_ON(stripe_index >= bbio->num_stripes);
- dev = bbio->stripes[stripe_index].dev;
+ struct btrfs_device *dev = btrfs_io_bio(bio)->dev;
if (dev->bdev) {
if (bio_op(bio) == REQ_OP_WRITE)
btrfs_dev_stat_inc_and_print(dev,
@@ -6313,13 +6308,12 @@ static void btrfs_end_bio(struct bio *bio)
}

static void submit_stripe_bio(struct btrfs_bio *bbio, struct bio *bio,
- u64 physical, int dev_nr)
+ u64 physical, struct btrfs_device *dev)
{
- struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
struct btrfs_fs_info *fs_info = bbio->fs_info;

bio->bi_private = bbio;
- btrfs_io_bio(bio)->stripe_index = dev_nr;
+ btrfs_io_bio(bio)->dev = dev;
bio->bi_end_io = btrfs_end_bio;
bio->bi_iter.bi_sector = physical >> 9;
btrfs_debug_in_rcu(fs_info,
@@ -6421,7 +6415,7 @@ blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
bio = first_bio;

submit_stripe_bio(bbio, bio, bbio->stripes[dev_nr].physical,
- dev_nr);
+ dev);
}
btrfs_bio_counter_dec(fs_info);
return BLK_STS_OK;
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 75af2334b2e3..95aa0cca21e6 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -288,7 +288,7 @@ struct btrfs_fs_devices {
*/
struct btrfs_io_bio {
unsigned int mirror_num;
- unsigned int stripe_index;
+ struct btrfs_device *dev;
u64 logical;
u8 *csum;
u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
--
2.17.1