libnvdimm: use devm_add_action_or_reset()

Clean up needless calls to the action routine by letting
devm_add_action_or_reset() call it automatically.  This does cause the
disk to registered and immediately unregistered when a memory allocation
fails, but the block layer should be prepared for such an event.
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/nvdimm/blk.c

@@ -267,10 +267,8 @@ static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
 	q = blk_alloc_queue(GFP_KERNEL);
 	if (!q)
 		return -ENOMEM;
-	if (devm_add_action(dev, nd_blk_release_queue, q)) {
-		blk_cleanup_queue(q);
+	if (devm_add_action_or_reset(dev, nd_blk_release_queue, q))
 		return -ENOMEM;
-	}
 
 	blk_queue_make_request(q, nd_blk_make_request);
 	blk_queue_max_hw_sectors(q, UINT_MAX);
@@ -282,10 +280,6 @@ static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
 	disk = alloc_disk(0);
 	if (!disk)
 		return -ENOMEM;
-	if (devm_add_action(dev, nd_blk_release_disk, disk)) {
-		put_disk(disk);
-		return -ENOMEM;
-	}
 
 	disk->driverfs_dev	= dev;
 	disk->first_minor	= 0;
@@ -296,6 +290,9 @@ static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
 	set_capacity(disk, 0);
 	add_disk(disk);
 
+	if (devm_add_action_or_reset(dev, nd_blk_release_disk, disk))
+		return -ENOMEM;
+
 	if (nsblk_meta_size(nsblk)) {
 		int rc = nd_integrity_init(disk, nsblk_meta_size(nsblk));
 

drivers/nvdimm/pmem.c

@@ -195,7 +195,7 @@ static void pmem_release_queue(void *q)
 	blk_cleanup_queue(q);
 }
 
-void pmem_release_disk(void *disk)
+static void pmem_release_disk(void *disk)
 {
 	del_gendisk(disk);
 	put_disk(disk);
@@ -269,10 +269,8 @@ static int pmem_attach_disk(struct device *dev,
 	 * At release time the queue must be dead before
 	 * devm_memremap_pages is unwound
 	 */
-	if (devm_add_action(dev, pmem_release_queue, q)) {
-		blk_cleanup_queue(q);
+	if (devm_add_action_or_reset(dev, pmem_release_queue, q))
 		return -ENOMEM;
-	}
 
 	if (IS_ERR(addr))
 		return PTR_ERR(addr);
@@ -288,10 +286,6 @@ static int pmem_attach_disk(struct device *dev,
 	disk = alloc_disk_node(0, nid);
 	if (!disk)
 		return -ENOMEM;
-	if (devm_add_action(dev, pmem_release_disk, disk)) {
-		put_disk(disk);
-		return -ENOMEM;
-	}
 
 	disk->fops		= &pmem_fops;
 	disk->queue		= q;
@@ -305,6 +299,10 @@ static int pmem_attach_disk(struct device *dev,
 	nvdimm_badblocks_populate(to_nd_region(dev->parent), &pmem->bb, res);
 	disk->bb = &pmem->bb;
 	add_disk(disk);
+
+	if (devm_add_action_or_reset(dev, pmem_release_disk, disk))
+		return -ENOMEM;
+
 	revalidate_disk(disk);
 
 	return 0;