Re: [PATCH v2 10/19] jfs: logmgr: use __bio_add_page to add single page to bio

[Dave Kleikamp <dave.kleikamp@oracle.com>]

On 3/30/23 5:43AM, Johannes Thumshirn wrote:
> The JFS IO 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-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>

> ---
>   fs/jfs/jfs_logmgr.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
> index 695415cbfe98..15c645827dec 100644
> --- a/fs/jfs/jfs_logmgr.c
> +++ b/fs/jfs/jfs_logmgr.c
> @@ -1974,7 +1974,7 @@ static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
>   
>   	bio = bio_alloc(log->bdev, 1, REQ_OP_READ, GFP_NOFS);
>   	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
> -	bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
> +	__bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
>   	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
>   
>   	bio->bi_end_io = lbmIODone;
> @@ -2115,7 +2115,7 @@ static void lbmStartIO(struct lbuf * bp)
>   
>   	bio = bio_alloc(log->bdev, 1, REQ_OP_WRITE | REQ_SYNC, GFP_NOFS);
>   	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
> -	bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
> +	__bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
>   	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
>   
>   	bio->bi_end_io = lbmIODone;