block/sd: Return -EREMOTEIO when WRITE SAME and DISCARD are disabled
When a storage device rejects a WRITE SAME command we will disable write
same functionality for the device and return -EREMOTEIO to the block
layer. -EREMOTEIO will in turn prevent DM from retrying the I/O and/or
failing the path.
Yiwen Jiang discovered a small race where WRITE SAME requests issued
simultaneously would cause -EIO to be returned. This happened because
any requests being prepared after WRITE SAME had been disabled for the
device caused us to return BLKPREP_KILL. The latter caused the block
layer to return -EIO upon completion.
To overcome this we introduce BLKPREP_INVALID which indicates that this
is an invalid request for the device. blk_peek_request() is modified to
return -EREMOTEIO in that case.
Reported-by: Yiwen Jiang <jiangyiwen@huawei.com>
Suggested-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index 476244d..35607dd 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2447,14 +2447,16 @@
rq = NULL;
break;
- } else if (ret == BLKPREP_KILL) {
+ } else if (ret == BLKPREP_KILL || ret == BLKPREP_INVALID) {
+ int err = (ret == BLKPREP_INVALID) ? -EREMOTEIO : -EIO;
+
rq->cmd_flags |= REQ_QUIET;
/*
* Mark this request as started so we don't trigger
* any debug logic in the end I/O path.
*/
blk_start_request(rq);
- __blk_end_request_all(rq, -EIO);
+ __blk_end_request_all(rq, err);
} else {
printk(KERN_ERR "%s: bad return=%d\n", __func__, ret);
break;