[076/115] dm mpath: disable blk_abort_queue

[Greg KH <gregkh@suse.de>]

2.6.32-longterm review patch.  If anyone has any objections, please let us know.

------------------

From: Mike Snitzer <snitzer@redhat.com>

commit 09c9d4c9b6a2b5909ae3c6265e4cd3820b636863 upstream.

Revert commit 224cb3e981f1b2f9f93dbd49eaef505d17d894c2
  dm: Call blk_abort_queue on failed paths

Multipath began to use blk_abort_queue() to allow for
lower latency path deactivation.  This was found to
cause list corruption:

   the cmd gets blk_abort_queued/timedout run on it and the scsi eh
   somehow is able to complete and run scsi_queue_insert while
   scsi_request_fn is still trying to process the request.

   https://www.redhat.com/archives/dm-devel/2010-November/msg00085.html

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Mike Anderson <andmike@linux.vnet.ibm.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/md/dm-mpath.c |   12 ------------
 1 file changed, 12 deletions(-)

--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -33,7 +33,6 @@ struct pgpath {
 	unsigned fail_count;		/* Cumulative failure count */
 
 	struct dm_path path;
-	struct work_struct deactivate_path;
 	struct work_struct activate_path;
 };
 
@@ -113,7 +112,6 @@ static struct workqueue_struct *kmultipa
 static void process_queued_ios(struct work_struct *work);
 static void trigger_event(struct work_struct *work);
 static void activate_path(struct work_struct *work);
-static void deactivate_path(struct work_struct *work);
 
 
 /*-----------------------------------------------
@@ -126,7 +124,6 @@ static struct pgpath *alloc_pgpath(void)
 
 	if (pgpath) {
 		pgpath->is_active = 1;
-		INIT_WORK(&pgpath->deactivate_path, deactivate_path);
 		INIT_WORK(&pgpath->activate_path, activate_path);
 	}
 
@@ -138,14 +135,6 @@ static void free_pgpath(struct pgpath *p
 	kfree(pgpath);
 }
 
-static void deactivate_path(struct work_struct *work)
-{
-	struct pgpath *pgpath =
-		container_of(work, struct pgpath, deactivate_path);
-
-	blk_abort_queue(pgpath->path.dev->bdev->bd_disk->queue);
-}
-
 static struct priority_group *alloc_priority_group(void)
 {
 	struct priority_group *pg;
@@ -949,7 +938,6 @@ static int fail_path(struct pgpath *pgpa
 		      pgpath->path.dev->name, m->nr_valid_paths);
 
 	schedule_work(&m->trigger_event);
-	queue_work(kmultipathd, &pgpath->deactivate_path);
 
 out:
 	spin_unlock_irqrestore(&m->lock, flags);