All of lore.kernel.org
 help / color / mirror / Atom feed
From: Hannes Reinecke <hare@suse.de>
To: Christoph Hellwig <hch@lst.de>
Cc: Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>,
	Keith Busch <keith.busch@wdc.com>,
	James Smart <james.smart@broadcom.com>,
	linux-nvme@lists.infradead.org, Hannes Reinecke <hare@suse.de>,
	Sagi Grimberg <sagi@grimberg.me>
Subject: [PATCH 2/3] nvme/fcloop: short-circuit LS requests if no association is present
Date: Fri,  6 Mar 2020 14:04:39 +0100	[thread overview]
Message-ID: <20200306130440.16864-3-hare@suse.de> (raw)
In-Reply-To: <20200306130440.16864-1-hare@suse.de>

If no association or targetport is present shifting LS processing
to a workqueue is a bad idea as the targetport itself is about
to be removed, and we would deadlock with targetport deletion.
So instead return an error directly and treat it as a send error,
avoiding the deadlock.

Signed-off-by: Hannes Reinecke <hare@suse.de>
---
 drivers/nvme/target/fcloop.c | 36 +++++++++---------------------------
 1 file changed, 9 insertions(+), 27 deletions(-)

diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c
index 3610b0bd12da..4f9435d9fa61 100644
--- a/drivers/nvme/target/fcloop.c
+++ b/drivers/nvme/target/fcloop.c
@@ -332,26 +332,17 @@ fcloop_h2t_ls_req(struct nvme_fc_local_port *localport,
 {
 	struct fcloop_lsreq *tls_req = lsreq->private;
 	struct fcloop_rport *rport = remoteport->private;
-	int ret = 0;
+
+	if (!rport->targetport)
+		return  -ECONNREFUSED;
 
 	tls_req->lsreq = lsreq;
 	INIT_LIST_HEAD(&tls_req->ls_list);
 
-	if (!rport->targetport) {
-		tls_req->status = -ECONNREFUSED;
-		spin_lock(&rport->lock);
-		list_add_tail(&rport->ls_list, &tls_req->ls_list);
-		spin_unlock(&rport->lock);
-		schedule_work(&rport->ls_work);
-		return ret;
-	}
-
 	tls_req->status = 0;
-	ret = nvmet_fc_rcv_ls_req(rport->targetport, rport,
+	return nvmet_fc_rcv_ls_req(rport->targetport, rport,
 				  &tls_req->ls_rsp,
 				  lsreq->rqstaddr, lsreq->rqstlen);
-
-	return ret;
 }
 
 static int
@@ -415,7 +406,9 @@ fcloop_t2h_ls_req(struct nvmet_fc_target_port *targetport, void *hosthandle,
 {
 	struct fcloop_lsreq *tls_req = lsreq->private;
 	struct fcloop_tport *tport = targetport->private;
-	int ret = 0;
+
+	if (!tport->remoteport)
+		return -ECONNREFUSED;
 
 	/*
 	 * hosthandle should be the dst.rport value.
@@ -425,20 +418,9 @@ fcloop_t2h_ls_req(struct nvmet_fc_target_port *targetport, void *hosthandle,
 	tls_req->lsreq = lsreq;
 	INIT_LIST_HEAD(&tls_req->ls_list);
 
-	if (!tport->remoteport) {
-		tls_req->status = -ECONNREFUSED;
-		spin_lock(&tport->lock);
-		list_add_tail(&tport->ls_list, &tls_req->ls_list);
-		spin_unlock(&tport->lock);
-		schedule_work(&tport->ls_work);
-		return ret;
-	}
-
 	tls_req->status = 0;
-	ret = nvme_fc_rcv_ls_req(tport->remoteport, &tls_req->ls_rsp,
-				 lsreq->rqstaddr, lsreq->rqstlen);
-
-	return ret;
+	return nvme_fc_rcv_ls_req(tport->remoteport, &tls_req->ls_rsp,
+				  lsreq->rqstaddr, lsreq->rqstlen);
 }
 
 static int
-- 
2.16.4


_______________________________________________
linux-nvme mailing list
linux-nvme@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-nvme

  parent reply	other threads:[~2020-03-06 13:05 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-06 13:04 [PATCH 0/3] nvmet/fcloop fixes Hannes Reinecke
2020-03-06 13:04 ` [PATCH 1/3] nvmet/fc: Sanitize tgtport reference counting for LS requests Hannes Reinecke
2020-03-06 22:11   ` Sagi Grimberg
2020-03-07  1:00   ` James Smart
2020-03-10 16:52   ` Christoph Hellwig
2020-03-06 13:04 ` Hannes Reinecke [this message]
2020-03-06 22:12   ` [PATCH 2/3] nvme/fcloop: short-circuit LS requests if no association is present Sagi Grimberg
2020-03-07  1:11   ` James Smart
2020-03-07  8:39     ` Hannes Reinecke
2020-03-06 13:04 ` [PATCH 3/3] nvme/fcloop: flush workqueue before calling nvme_fc_unregister_remoteport() Hannes Reinecke
2020-03-06 22:12   ` Sagi Grimberg
2020-03-07  1:12   ` James Smart
2020-03-07  8:41     ` Hannes Reinecke
2020-03-31 14:24 ` [PATCH 0/3] nvmet/fcloop fixes Christoph Hellwig
2020-04-16 10:37   ` Hannes Reinecke

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=20200306130440.16864-3-hare@suse.de \
    --to=hare@suse.de \
    --cc=Chaitanya.Kulkarni@wdc.com \
    --cc=hch@lst.de \
    --cc=james.smart@broadcom.com \
    --cc=keith.busch@wdc.com \
    --cc=linux-nvme@lists.infradead.org \
    --cc=sagi@grimberg.me \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.