4 files changed, 22 insertions, 18 deletions
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index ca4abe1ccd8d..3fba31cea66e 100644
--- a/drivers/md/bcache/alloc.c
+++ b/drivers/md/bcache/alloc.c
@@ -404,7 +404,8 @@ long bch_bucket_alloc(struct cache *ca, unsigned reserve, bool wait)
 
 	finish_wait(&ca->set->bucket_wait, &w);
 out:
-	wake_up_process(ca->alloc_thread);
+	if (ca->alloc_thread)
+		wake_up_process(ca->alloc_thread);
 
 	trace_bcache_alloc(ca, reserve);
 
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index 8bf9667ff46b..7643f72adb1c 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -937,7 +937,8 @@ static void __get_memory_limit(struct dm_bufio_client *c,
 		buffers = c->minimum_buffers;
 
 	*limit_buffers = buffers;
-	*threshold_buffers = buffers * DM_BUFIO_WRITEBACK_PERCENT / 100;
+	*threshold_buffers = mult_frac(buffers,
+				       DM_BUFIO_WRITEBACK_PERCENT, 100);
 }
 
 /*
@@ -1856,19 +1857,15 @@ static int __init dm_bufio_init(void)
 	memset(&dm_bufio_caches, 0, sizeof dm_bufio_caches);
 	memset(&dm_bufio_cache_names, 0, sizeof dm_bufio_cache_names);
 
-	mem = (__u64)((totalram_pages - totalhigh_pages) *
-		      DM_BUFIO_MEMORY_PERCENT / 100) << PAGE_SHIFT;
+	mem = (__u64)mult_frac(totalram_pages - totalhigh_pages,
+			       DM_BUFIO_MEMORY_PERCENT, 100) << PAGE_SHIFT;
 
 	if (mem > ULONG_MAX)
 		mem = ULONG_MAX;
 
 #ifdef CONFIG_MMU
-	/*
-	 * Get the size of vmalloc space the same way as VMALLOC_TOTAL
-	 * in fs/proc/internal.h
-	 */
-	if (mem > (VMALLOC_END - VMALLOC_START) * DM_BUFIO_VMALLOC_PERCENT / 100)
-		mem = (VMALLOC_END - VMALLOC_START) * DM_BUFIO_VMALLOC_PERCENT / 100;
+	if (mem > mult_frac(VMALLOC_TOTAL, DM_BUFIO_VMALLOC_PERCENT, 100))
+		mem = mult_frac(VMALLOC_TOTAL, DM_BUFIO_VMALLOC_PERCENT, 100);
 #endif
 
 	dm_bufio_default_cache_size = mem;
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h
index 40ceba1fe8be..1609d4971104 100644
--- a/drivers/md/dm-core.h
+++ b/drivers/md/dm-core.h
@@ -29,7 +29,6 @@ struct dm_kobject_holder {
  * DM targets must _not_ deference a mapped_device to directly access its members!
  */
 struct mapped_device {
-	struct srcu_struct io_barrier;
 	struct mutex suspend_lock;
 
 	/*
@@ -127,6 +126,8 @@ struct mapped_device {
 	struct blk_mq_tag_set *tag_set;
 	bool use_blk_mq:1;
 	bool init_tio_pdu:1;
+
+	struct srcu_struct io_barrier;
 };
 
 void dm_init_md_queue(struct mapped_device *md);
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index e66f4040d84b..c5522551122f 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -21,6 +21,7 @@
 #include <linux/delay.h>
 #include <linux/wait.h>
 #include <linux/pr.h>
+#include <linux/vmalloc.h>
 
 #define DM_MSG_PREFIX "core"
 
@@ -1511,7 +1512,7 @@ static struct mapped_device *alloc_dev(int minor)
 	struct mapped_device *md;
 	void *old_md;
 
-	md = kzalloc_node(sizeof(*md), GFP_KERNEL, numa_node_id);
+	md = vzalloc_node(sizeof(*md), numa_node_id);
 	if (!md) {
 		DMWARN("unable to allocate device, out of memory.");
 		return NULL;
@@ -1605,7 +1606,7 @@ bad_io_barrier:
 bad_minor:
 	module_put(THIS_MODULE);
 bad_module_get:
-	kfree(md);
+	kvfree(md);
 	return NULL;
 }
 
@@ -1624,7 +1625,7 @@ static void free_dev(struct mapped_device *md)
 	free_minor(minor);
 
 	module_put(THIS_MODULE);
-	kfree(md);
+	kvfree(md);
 }
 
 static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
@@ -2514,11 +2515,15 @@ struct mapped_device *dm_get_from_kobject(struct kobject *kobj)
 
 	md = container_of(kobj, struct mapped_device, kobj_holder.kobj);
 
-	if (test_bit(DMF_FREEING, &md->flags) ||
-	    dm_deleting_md(md))
-		return NULL;
-
+	spin_lock(&_minor_lock);
+	if (test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) {
+		md = NULL;
+		goto out;
+	}
 	dm_get(md);
+out:
+	spin_unlock(&_minor_lock);
+
 	return md;
 }