Merge tag 'dm-4.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:
 "Two fixes for 4.4-rc1's DM ioctl changes that introduced the potential
  for infinite recursion on ioctl (with DM multipath).

  And four stable fixes:

   - A DM thin-provisioning fix to restore 'error_if_no_space' setting
     when a thin-pool is made writable again (after having been out of
     space).

   - A DM thin-provisioning fix to properly advertise discard support
     for thin volumes that are stacked on a thin-pool whose underlying
     data device doesn't support discards.

   - A DM ioctl fix to allow ctrl-c to break out of an ioctl retry loop
     when DM multipath is configured to 'queue_if_no_path'.

   - A DM crypt fix for a possible hang on dm-crypt device removal"

* tag 'dm-4.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm thin: fix regression in advertised discard limits
  dm crypt: fix a possible hang due to race condition on exit
  dm mpath: fix infinite recursion in ioctl when no paths and !queue_if_no_path
  dm: do not reuse dm_blk_ioctl block_device input as local variable
  dm: fix ioctl retry termination with signal
  dm thin: restore requested 'error_if_no_space' setting on OODS to WRITE transition

1 files changed, 16 insertions, 14 deletions

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index aaa6caa46a9f..cfa29f574c2a 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1537,32 +1537,34 @@ static int multipath_prepare_ioctl(struct dm_target *ti,
 		struct block_device **bdev, fmode_t *mode)
 {
 	struct multipath *m = ti->private;
-	struct pgpath *pgpath;
 	unsigned long flags;
 	int r;
 
-	r = 0;
-
 	spin_lock_irqsave(&m->lock, flags);
 
 	if (!m->current_pgpath)
 		__choose_pgpath(m, 0);
 
-	pgpath = m->current_pgpath;
-
-	if (pgpath) {
-		*bdev = pgpath->path.dev->bdev;
-		*mode = pgpath->path.dev->mode;
+	if (m->current_pgpath) {
+		if (!m->queue_io) {
+			*bdev = m->current_pgpath->path.dev->bdev;
+			*mode = m->current_pgpath->path.dev->mode;
+			r = 0;
+		} else {
+			/* pg_init has not started or completed */
+			r = -ENOTCONN;
+		}
+	} else {
+		/* No path is available */
+		if (m->queue_if_no_path)
+			r = -ENOTCONN;
+		else
+			r = -EIO;
 	}
 
-	if ((pgpath && m->queue_io) || (!pgpath && m->queue_if_no_path))
-		r = -ENOTCONN;
-	else if (!*bdev)
-		r = -EIO;
-
 	spin_unlock_irqrestore(&m->lock, flags);
 
-	if (r == -ENOTCONN && !fatal_signal_pending(current)) {
+	if (r == -ENOTCONN) {
 		spin_lock_irqsave(&m->lock, flags);
 		if (!m->current_pg) {
 			/* Path status changed, redo selection */