[05/19] md: use __bio_add_page to add single page

Commit Message

Johannes Thumshirn March 29, 2023, 5:05 p.m. UTC

The md-raid superblock writing code uses bio_add_page() to add a page to a
newly created bio. bio_add_page() can fail, but the return value is never
checked.

Use __bio_add_page() as adding a single page to a newly created bio is
guaranteed to succeed.

This brings us a step closer to marking bio_add_page() as __must_check.

Signed-of_-by: Johannes Thumshirn <[e-mail]>
---
 drivers/md/md.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Damien Le Moal March 29, 2023, 11:31 p.m. UTC | #1

On 3/30/23 02:05, Johannes Thumshirn wrote:
> The md-raid superblock writing code uses bio_add_page() to add a page to a
> newly created bio. bio_add_page() can fail, but the return value is never
> checked.
> 
> Use __bio_add_page() as adding a single page to a newly created bio is
> guaranteed to succeed.
> 
> This brings us a step closer to marking bio_add_page() as __must_check.
> 
> Signed-of_-by: Johannes Thumshirn <[e-mail]>

Reviewed-by: Damien Le Moal <[e-mail]>

Patch

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 39e49e5d7182..e730c3627d00 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -958,7 +958,7 @@  void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
 	atomic_inc(&rdev->nr_pending);
 
 	bio->bi_iter.bi_sector = sector;
-	bio_add_page(bio, page, size, 0);
+	__bio_add_page(bio, page, size, 0);
 	bio->bi_private = rdev;
 	bio->bi_end_io = super_written;
 
@@ -999,7 +999,7 @@  int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
 		bio.bi_iter.bi_sector = sector + rdev->new_data_offset;
 	else
 		bio.bi_iter.bi_sector = sector + rdev->data_offset;
-	bio_add_page(&bio, page, size, 0);
+	__bio_add_page(&bio, page, size, 0);
 
 	submit_bio_wait(&bio);