Commit 640eb3b0 authored by Stefan Bader's avatar Stefan Bader Committed by Linus Torvalds
Browse files

[PATCH] device-mapper dm-mpath: endio spinlock fix 



do_end_io() can be called without interrupts blocked.

Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 0e56822d

drivers/md/dm-mpath.c

+7 −6
Original line number Diff line number Diff line
@@ -1000,6 +1000,7 @@ static int do_end_io(struct multipath *m, struct bio *bio, 
{

	struct hw_handler *hwh = &m->hw_handler;

	unsigned err_flags = MP_FAIL_PATH;	/* Default behavior */

	unsigned long flags;



	if (!error)

		return 0;	/* I/O complete */
@@ -1010,17 +1011,17 @@ static int do_end_io(struct multipath *m, struct bio *bio, 
	if (error == -EOPNOTSUPP)

		return error;



	spin_lock(&m->lock);

	spin_lock_irqsave(&m->lock, flags);

	if (!m->nr_valid_paths) {

		if (!m->queue_if_no_path) {

			spin_unlock(&m->lock);

			spin_unlock_irqrestore(&m->lock, flags);

			return -EIO;

		} else {

			spin_unlock(&m->lock);

			spin_unlock_irqrestore(&m->lock, flags);

			goto requeue;

		}

	}

	spin_unlock(&m->lock);

	spin_unlock_irqrestore(&m->lock, flags);



	if (hwh->type && hwh->type->error)

		err_flags = hwh->type->error(hwh, bio);
@@ -1040,12 +1041,12 @@ static int do_end_io(struct multipath *m, struct bio *bio, 
	dm_bio_restore(&mpio->details, bio);



	/* queue for the daemon to resubmit or fail */

	spin_lock(&m->lock);

	spin_lock_irqsave(&m->lock, flags);

	bio_list_add(&m->queued_ios, bio);

	m->queue_size++;

	if (!m->queue_io)

		queue_work(kmultipathd, &m->process_queued_ios);

	spin_unlock(&m->lock);

	spin_unlock_irqrestore(&m->lock, flags);



	return 1;	/* io not complete */

}