[PATCH v3 01/30] block: Do not force full zone append completion in req_bio_endio()

[Bart Van Assche]

On 3/27/24 17:43, Damien Le Moal wrote:
> This reverts commit 748dc0b65ec2b4b7b3dbd7befcc4a54fdcac7988.
> 
> Partial zone append completions cannot be supported as there is no
> guarantees that the fragmented data will be written sequentially in the
> same manner as with a full command. Commit 748dc0b65ec2 ("block: fix
> partial zone append completion handling in req_bio_endio()") changed
> req_bio_endio() to always advance a partially failed BIO by its full
> length, but this can lead to incorrect accounting. So revert this
> change and let low level device drivers handle this case by always
> failing completely zone append operations. With this revert, users will
> still see an IO error for a partially completed zone append BIO.
> 
> Fixes: 748dc0b65ec2 ("block: fix partial zone append completion handling in req_bio_endio()")
> Cc: stable at vger.kernel.org
> Signed-off-by: Damien Le Moal <dlemoal at kernel.org>
> ---
>   block/blk-mq.c | 9 ++-------
>   1 file changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 555ada922cf0..32afb87efbd0 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -770,16 +770,11 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
>   		/*
>   		 * Partial zone append completions cannot be supported as the
>   		 * BIO fragments may end up not being written sequentially.
> -		 * For such case, force the completed nbytes to be equal to
> -		 * the BIO size so that bio_advance() sets the BIO remaining
> -		 * size to 0 and we end up calling bio_endio() before returning.
>   		 */
> -		if (bio->bi_iter.bi_size != nbytes) {
> +		if (bio->bi_iter.bi_size != nbytes)
>   			bio->bi_status = BLK_STS_IOERR;
> -			nbytes = bio->bi_iter.bi_size;
> -		} else {
> +		else
>   			bio->bi_iter.bi_sector = rq->__sector;
> -		}
>   	}
>   
>   	bio_advance(bio, nbytes);

Hi Damien,

This patch looks good to me but shouldn't it be separated from this
patch series? I think that will help this patch to get merged sooner.

Thanks,

Bart.