On Wed, 3 Feb 2016, jiangyiwen wrote:
> Date: Wed, 3 Feb 2016 17:54:36 +0800
> From: jiangyiwen <jiangyi...@huawei.com>
> To: ax...@kernel.dk, linux-kernel@vger.kernel.org
> Cc: dm-de...@redhat.com, martin.peter...@oracle.com,
> Lukáš Czerner <lczer...@redhat.com>, xuejiu...@huawei.com,
> "Qijiang (Joseph, Euler)" <joseph...@huawei.com>
> Subject: [dm-devel] [PATCH] block: do not return -EOPNOTSUPP only when issue a
> discard request
>
> commit 8af1954d172a("blkdev: Do not return -EOPNOTSUPP if discard
> is supported") only solve the situation of discard, because When
> applications issue a discard request to device, they can't expect
> deterministic behaviour. However, WRITE SAME should not ignore error
> with EOPNOTSUPP, because if applications issue WRITE SAME requests to
> device, it should return deterministic results to applications
> according to the T10 standard, or else it will cause an inconsistent
> state between upper layer and bottom layer.
>
> So ignoring error with EOPNOTSUPP only in discard situation.
>
> Signed-off-by: Yiwen Jiang <jiangyi...@huawei.com>
Looks good.
Reviewed-by: Lukas Czerner <lczer...@redhat.com>
Thanks!
-Lukas
> ---
> block/blk-lib.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/block/blk-lib.c b/block/blk-lib.c
> index 9ebf653..e4f02f1 100644
> --- a/block/blk-lib.c
> +++ b/block/blk-lib.c
> @@ -19,7 +19,9 @@ static void bio_batch_end_io(struct bio *bio)
> {
> struct bio_batch *bb = bio->bi_private;
>
> - if (bio->bi_error && bio->bi_error != -EOPNOTSUPP)
> + /* ignore -EOPNOTSUPP only when issue a discard request */
> + if (bio->bi_error && (!(bio->bi_rw & REQ_DISCARD) ||
> + (bio->bi_error != -EOPNOTSUPP)))
> bb->error = bio->bi_error;
> if (atomic_dec_and_test(&bb->done))
> complete(bb->wait);
>
