Linux-Block Archive on lore.kernel.org
 help / color / Atom feed
From: Mike Snitzer <snitzer@redhat.com>
To: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>
Cc: dm-devel@redhat.com, linux-block@vger.kernel.org,
	linux-nvme@lists.infradead.org
Subject: [PATCH v2 3/4] nvme: introduce FAILUP handling for REQ_FAILFAST_TRANSPORT
Date: Thu, 15 Apr 2021 19:15:29 -0400
Message-ID: <20210415231530.95464-4-snitzer@redhat.com> (raw)
In-Reply-To: <20210415231530.95464-1-snitzer@redhat.com>

If REQ_FAILFAST_TRANSPORT is set it means the driver should not retry
IO that completed with transport errors. REQ_FAILFAST_TRANSPORT is
set by multipathing software (e.g. dm-multipath) before it issues IO.

Update NVMe to allow failover of requests marked with either
REQ_NVME_MPATH or REQ_FAILFAST_TRANSPORT. This allows such requests
to be given a disposition of either FAILOVER or FAILUP respectively.
FAILUP handling ensures a retryable error is returned up from NVMe.

Introduce nvme_failup_req() for use in nvme_complete_rq() if
nvme_decide_disposition() returns FAILUP. nvme_failup_req() ensures
the request is completed with a retryable IO error when appropriate.
__nvme_end_req() was factored out for use by both nvme_end_req() and
nvme_failup_req().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
 drivers/nvme/host/core.c | 31 ++++++++++++++++++++++++++-----
 1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 4134cf3c7e48..10375197dd53 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -299,6 +299,7 @@ enum nvme_disposition {
 	COMPLETE,
 	RETRY,
 	FAILOVER,
+	FAILUP,
 };
 
 static inline enum nvme_disposition nvme_decide_disposition(struct request *req)
@@ -318,10 +319,11 @@ static inline enum nvme_disposition nvme_decide_disposition(struct request *req)
 	    nvme_req(req)->retries >= nvme_max_retries)
 		return COMPLETE;
 
-	if (req->cmd_flags & REQ_NVME_MPATH) {
+	if (req->cmd_flags & (REQ_NVME_MPATH | REQ_FAILFAST_TRANSPORT)) {
 		if (nvme_is_path_error(nvme_req(req)->status) ||
 		    blk_queue_dying(req->q))
-			return FAILOVER;
+			return (req->cmd_flags & REQ_NVME_MPATH) ?
+				FAILOVER : FAILUP;
 	} else {
 		if (blk_queue_dying(req->q))
 			return COMPLETE;
@@ -330,10 +332,8 @@ static inline enum nvme_disposition nvme_decide_disposition(struct request *req)
 	return RETRY;
 }
 
-static inline void nvme_end_req(struct request *req)
+static inline void __nvme_end_req(struct request *req, blk_status_t status)
 {
-	blk_status_t status = nvme_error_status(nvme_req(req)->status);
-
 	if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
 	    req_op(req) == REQ_OP_ZONE_APPEND)
 		req->__sector = nvme_lba_to_sect(req->q->queuedata,
@@ -343,6 +343,24 @@ static inline void nvme_end_req(struct request *req)
 	blk_mq_end_request(req, status);
 }
 
+static inline void nvme_end_req(struct request *req)
+{
+	__nvme_end_req(req, nvme_error_status(nvme_req(req)->status));
+}
+
+static void nvme_failup_req(struct request *req)
+{
+	blk_status_t status = nvme_error_status(nvme_req(req)->status);
+
+	if (WARN_ON_ONCE(!blk_path_error(status))) {
+		pr_debug("Request meant for failover but blk_status_t (errno=%d) was not retryable.\n",
+			 blk_status_to_errno(status));
+		status = BLK_STS_IOERR;
+	}
+
+	__nvme_end_req(req, status);
+}
+
 void nvme_complete_rq(struct request *req)
 {
 	trace_nvme_complete_rq(req);
@@ -361,6 +379,9 @@ void nvme_complete_rq(struct request *req)
 	case FAILOVER:
 		nvme_failover_req(req);
 		return;
+	case FAILUP:
+		nvme_failup_req(req);
+		return;
 	}
 }
 EXPORT_SYMBOL_GPL(nvme_complete_rq);
-- 
2.15.0


  parent reply index

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-15 23:15 [PATCH v2 0/4] nvme: improve error handling and ana_state to work well with dm-multipath Mike Snitzer
2021-04-15 23:15 ` [PATCH v2 1/4] nvme: return BLK_STS_DO_NOT_RETRY if the DNR bit is set Mike Snitzer
2021-04-15 23:48   ` Chaitanya Kulkarni
2021-04-16 13:51   ` Hannes Reinecke
2021-04-15 23:15 ` [PATCH v2 2/4] nvme: allow local retry for requests with REQ_FAILFAST_TRANSPORT set Mike Snitzer
2021-04-16 14:01   ` Hannes Reinecke
2021-04-16 14:53     ` Mike Snitzer
2021-04-16 15:20       ` Hannes Reinecke
2021-04-16 15:32         ` Mike Snitzer
2021-04-15 23:15 ` Mike Snitzer [this message]
2021-04-16 14:07   ` [PATCH v2 3/4] nvme: introduce FAILUP handling for REQ_FAILFAST_TRANSPORT Hannes Reinecke
2021-04-16 15:03     ` Mike Snitzer
2021-04-16 16:23       ` Hannes Reinecke
2021-04-16 20:03     ` [dm-devel] " Ewan D. Milne
2021-04-16 20:52   ` Ewan D. Milne
2021-04-16 21:44     ` Mike Snitzer
2021-04-15 23:15 ` [PATCH v2 4/4] nvme: decouple basic ANA log page re-read support from native multipathing Mike Snitzer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210415231530.95464-4-snitzer@redhat.com \
    --to=snitzer@redhat.com \
    --cc=axboe@kernel.dk \
    --cc=dm-devel@redhat.com \
    --cc=hch@lst.de \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-nvme@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Block Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-block/0 linux-block/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-block linux-block/ https://lore.kernel.org/linux-block \
		linux-block@vger.kernel.org
	public-inbox-index linux-block

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-block


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git