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

Pull device mapper updates from Mike Snitzer:
 "Smaller set of DM changes for this merge.  I've based these changes on
  Jens' for-4.4/reservations branch because the associated DM changes
  required it.

   - Revert a dm-multipath change that caused a regression for
     unprivledged users (e.g. kvm guests) that issued ioctls when a
     multipath device had no available paths.

   - Include Christoph's refactoring of DM's ioctl handling and add
     support for passing through persistent reservations with DM
     multipath.

   - All other changes are very simple cleanups"

* tag 'dm-4.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm switch: simplify conditional in alloc_region_table()
  dm delay: document that offsets are specified in sectors
  dm delay: capitalize the start of an delay_ctr() error message
  dm delay: Use DM_MAPIO macros instead of open-coded equivalents
  dm linear: remove redundant target name from error messages
  dm persistent data: eliminate unnecessary return values
  dm: eliminate unused "bioset" process for each bio-based DM device
  dm: convert ffs to __ffs
  dm: drop NULL test before kmem_cache_destroy() and mempool_destroy()
  dm: add support for passing through persistent reservations
  dm: refactor ioctl handling
  Revert "dm mpath: fix stalls when handling invalid ioctls"
  dm: initialize non-blk-mq queue data before queue is used

1 files changed, 13 insertions, 21 deletions

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 5a67671..aaa6caa 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1533,18 +1533,14 @@ out:
 	return r;
 }
 
-static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
-			   unsigned long arg)
+static int multipath_prepare_ioctl(struct dm_target *ti,
+		struct block_device **bdev, fmode_t *mode)
 {
 	struct multipath *m = ti->private;
 	struct pgpath *pgpath;
-	struct block_device *bdev;
-	fmode_t mode;
 	unsigned long flags;
 	int r;
 
-	bdev = NULL;
-	mode = 0;
 	r = 0;
 
 	spin_lock_irqsave(&m->lock, flags);
@@ -1555,26 +1551,17 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
 	pgpath = m->current_pgpath;
 
 	if (pgpath) {
-		bdev = pgpath->path.dev->bdev;
-		mode = pgpath->path.dev->mode;
+		*bdev = pgpath->path.dev->bdev;
+		*mode = pgpath->path.dev->mode;
 	}
 
 	if ((pgpath && m->queue_io) || (!pgpath && m->queue_if_no_path))
 		r = -ENOTCONN;
-	else if (!bdev)
+	else if (!*bdev)
 		r = -EIO;
 
 	spin_unlock_irqrestore(&m->lock, flags);
 
-	/*
-	 * Only pass ioctls through if the device sizes match exactly.
-	 */
-	if (!bdev || ti->len != i_size_read(bdev->bd_inode) >> SECTOR_SHIFT) {
-		int err = scsi_verify_blk_ioctl(NULL, cmd);
-		if (err)
-			r = err;
-	}
-
 	if (r == -ENOTCONN && !fatal_signal_pending(current)) {
 		spin_lock_irqsave(&m->lock, flags);
 		if (!m->current_pg) {
@@ -1587,7 +1574,12 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
 		dm_table_run_md_queue_async(m->ti->table);
 	}
 
-	return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
+	/*
+	 * Only pass ioctls through if the device sizes match exactly.
+	 */
+	if (!r && ti->len != i_size_read((*bdev)->bd_inode) >> SECTOR_SHIFT)
+		return 1;
+	return r;
 }
 
 static int multipath_iterate_devices(struct dm_target *ti,
@@ -1690,7 +1682,7 @@ out:
  *---------------------------------------------------------------*/
 static struct target_type multipath_target = {
 	.name = "multipath",
-	.version = {1, 9, 0},
+	.version = {1, 10, 0},
 	.module = THIS_MODULE,
 	.ctr = multipath_ctr,
 	.dtr = multipath_dtr,
@@ -1703,7 +1695,7 @@ static struct target_type multipath_target = {
 	.resume = multipath_resume,
 	.status = multipath_status,
 	.message = multipath_message,
-	.ioctl  = multipath_ioctl,
+	.prepare_ioctl = multipath_prepare_ioctl,
 	.iterate_devices = multipath_iterate_devices,
 	.busy = multipath_busy,
 };