mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Philipp Reisner <philipp.reisner@linbit.com>
To: linux-kernel@vger.kernel.org, Jens Axboe <axboe@kernel.dk>
Cc: drbd-dev@lists.linbit.com,
	Lars Ellenberg <lars.ellenberg@linbit.com>,
	Philipp Reisner <philipp.reisner@linbit.com>
Subject: [PATCH 09/17] drbd: only fail empty flushes if no good data is reachable
Date: Wed, 27 Mar 2013 14:08:41 +0100	[thread overview]
Message-ID: <1364389729-17559-10-git-send-email-philipp.reisner@linbit.com> (raw)
In-Reply-To: <1364389729-17559-1-git-send-email-philipp.reisner@linbit.com>

From: Lars Ellenberg <lars.ellenberg@linbit.com>

We completed empty flushes (blkdev_issue_flush()) with IO error
if we lost the local disk, even if we still have an established
replication link to a healthy remote disk.

Fix this to only report errors to upper layers,
if neither local nor remote data is reachable.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
 drivers/block/drbd/drbd_req.c |   12 ++++++++----
 drivers/block/drbd/drbd_req.h |    8 ++++++++
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 9f7ff1c..beefe65 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -263,8 +263,7 @@ void drbd_req_complete(struct drbd_request *req, struct bio_and_error *m)
 		else
 			root = &mdev->read_requests;
 		drbd_remove_request_interval(root, req);
-	} else if (!(s & RQ_POSTPONED))
-		D_ASSERT((s & (RQ_NET_MASK & ~RQ_NET_DONE)) == 0);
+	}
 
 	/* Before we can signal completion to the upper layers,
 	 * we may need to close the current transfer log epoch.
@@ -755,6 +754,11 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		D_ASSERT(req->rq_state & RQ_NET_PENDING);
 		mod_rq_state(req, m, RQ_NET_PENDING, RQ_NET_OK|RQ_NET_DONE);
 		break;
+
+	case QUEUE_AS_DRBD_BARRIER:
+		start_new_tl_epoch(mdev->tconn);
+		mod_rq_state(req, m, 0, RQ_NET_OK|RQ_NET_DONE);
+		break;
 	};
 
 	return rv;
@@ -975,8 +979,8 @@ static int drbd_process_write_request(struct drbd_request *req)
 		/* The only size==0 bios we expect are empty flushes. */
 		D_ASSERT(req->master_bio->bi_rw & REQ_FLUSH);
 		if (remote)
-			start_new_tl_epoch(mdev->tconn);
-		return 0;
+			_req_mod(req, QUEUE_AS_DRBD_BARRIER);
+		return remote;
 	}
 
 	if (!remote && !send_oos)
diff --git a/drivers/block/drbd/drbd_req.h b/drivers/block/drbd/drbd_req.h
index c08d229..978cb1a 100644
--- a/drivers/block/drbd/drbd_req.h
+++ b/drivers/block/drbd/drbd_req.h
@@ -88,6 +88,14 @@ enum drbd_req_event {
 	QUEUE_FOR_NET_READ,
 	QUEUE_FOR_SEND_OOS,
 
+	/* An empty flush is queued as P_BARRIER,
+	 * which will cause it to complete "successfully",
+	 * even if the local disk flush failed.
+	 *
+	 * Just like "real" requests, empty flushes (blkdev_issue_flush()) will
+	 * only see an error if neither local nor remote data is reachable. */
+	QUEUE_AS_DRBD_BARRIER,
+
 	SEND_CANCELED,
 	SEND_FAILED,
 	HANDED_OVER_TO_NETWORK,
-- 
1.7.9.5


  parent reply	other threads:[~2013-03-27 13:12 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-27 13:08 [PATCH 00/17] RFC: Pile of DRBD fixes Philipp Reisner
2013-03-27 13:08 ` [PATCH 01/17] idr: document exit conditions on idr_for_each_entry better Philipp Reisner
2013-03-27 13:08 ` [PATCH 02/17] drbd: reset ap_in_flight counter for new connections Philipp Reisner
2013-03-27 13:08 ` [PATCH 03/17] drbd: abort start of resync early, if it raced with connection breakage Philipp Reisner
2013-03-27 13:08 ` [PATCH 04/17] drbd: move invalidating the whole bitmap out of after_state ch() Philipp Reisner
2013-03-27 13:08 ` [PATCH 05/17] drbd: fix effective error returned when refusing an invalidate Philipp Reisner
2013-03-27 13:08 ` [PATCH 06/17] drbd: drop now useless duplicate state request from invalidate Philipp Reisner
2013-03-27 13:08 ` [PATCH 07/17] drbd: fix spurious warning about bitmap being locked from detach Philipp Reisner
2013-03-27 13:08 ` [PATCH 08/17] drbd: Fix disconnect to keep the peer disk state if connection breaks during operation Philipp Reisner
2013-03-27 13:08 ` Philipp Reisner [this message]
2013-03-27 13:08 ` [PATCH 10/17] drbd: fix memory leak Philipp Reisner
2013-03-27 13:08 ` [PATCH 11/17] drbd: validate resync_after dependency on attach already Philipp Reisner
2013-03-27 13:08 ` [PATCH 12/17] drbd: Fix build error when CONFIG_CRYPTO_HMAC is not set Philipp Reisner
2013-03-27 13:08 ` [PATCH 13/17] drbd: fix drbd epoch write count for ahead/behind mode Philipp Reisner
2013-03-27 13:08 ` [PATCH 14/17] drbd: add module_put() on error path in drbd_proc_open() Philipp Reisner
2013-03-27 13:08 ` [PATCH 15/17] drbd: fix for deadlock when using automatic split-brain-recovery Philipp Reisner
2013-03-27 13:08 ` [PATCH 16/17] drbd: use sched_setscheduler() Philipp Reisner
2013-03-27 13:08 ` [PATCH 17/17] drbd: fix if(); found by kbuild test robot Philipp Reisner
2013-03-28 16:11 ` [PATCH 00/17] RFC: Pile of DRBD fixes Jens Axboe

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=1364389729-17559-10-git-send-email-philipp.reisner@linbit.com \
    --to=philipp.reisner@linbit.com \
    --cc=axboe@kernel.dk \
    --cc=drbd-dev@lists.linbit.com \
    --cc=lars.ellenberg@linbit.com \
    --cc=linux-kernel@vger.kernel.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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome