diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 6b65a538d91d6f670435584ba218ef97849e7b6a..a69658b18dc9f59117604fab07aaa398ba7980f8 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -28,7 +28,7 @@ struct dm_file {
 	 * poll will wait until the global event number is greater than
 	 * this value.
 	 */
-	unsigned global_event_nr;
+	volatile unsigned global_event_nr;
 };
 
 /*-----------------------------------------------------------------
@@ -464,9 +464,9 @@ void dm_deferred_remove(void)
  * All the ioctl commands get dispatched to functions with this
  * prototype.
  */
-typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size);
+typedef int (*ioctl_fn)(struct file *filp, struct dm_ioctl *param, size_t param_size);
 
-static int remove_all(struct dm_ioctl *param, size_t param_size)
+static int remove_all(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false);
 	param->data_size = 0;
@@ -499,7 +499,7 @@ static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
 	return ((void *) param) + param->data_start;
 }
 
-static int list_devices(struct dm_ioctl *param, size_t param_size)
+static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	unsigned int i;
 	struct hash_cell *hc;
@@ -590,7 +590,7 @@ static void list_version_get_info(struct target_type *tt, void *param)
     info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
 }
 
-static int list_versions(struct dm_ioctl *param, size_t param_size)
+static int list_versions(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	size_t len, needed = 0;
 	struct dm_target_versions *vers;
@@ -732,7 +732,7 @@ static void __dev_status(struct mapped_device *md, struct dm_ioctl *param)
 	}
 }
 
-static int dev_create(struct dm_ioctl *param, size_t param_size)
+static int dev_create(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	int r, m = DM_ANY_MINOR;
 	struct mapped_device *md;
@@ -824,7 +824,7 @@ static struct mapped_device *find_device(struct dm_ioctl *param)
 	return md;
 }
 
-static int dev_remove(struct dm_ioctl *param, size_t param_size)
+static int dev_remove(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	struct hash_cell *hc;
 	struct mapped_device *md;
@@ -889,7 +889,7 @@ static int invalid_str(char *str, void *end)
 	return -EINVAL;
 }
 
-static int dev_rename(struct dm_ioctl *param, size_t param_size)
+static int dev_rename(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	int r;
 	char *new_data = (char *) param + param->data_start;
@@ -919,7 +919,7 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
 	return 0;
 }
 
-static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
+static int dev_set_geometry(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	int r = -EINVAL, x;
 	struct mapped_device *md;
@@ -1068,7 +1068,7 @@ static int do_resume(struct dm_ioctl *param)
  * Set or unset the suspension state of a device.
  * If the device already is in the requested state we just return its status.
  */
-static int dev_suspend(struct dm_ioctl *param, size_t param_size)
+static int dev_suspend(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	if (param->flags & DM_SUSPEND_FLAG)
 		return do_suspend(param);
@@ -1080,7 +1080,7 @@ static int dev_suspend(struct dm_ioctl *param, size_t param_size)
  * Copies device info back to user space, used by
  * the create and info ioctls.
  */
-static int dev_status(struct dm_ioctl *param, size_t param_size)
+static int dev_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	struct mapped_device *md;
 
@@ -1171,7 +1171,7 @@ static void retrieve_status(struct dm_table *table,
 /*
  * Wait for a device to report an event
  */
-static int dev_wait(struct dm_ioctl *param, size_t param_size)
+static int dev_wait(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	int r = 0;
 	struct mapped_device *md;
@@ -1208,6 +1208,19 @@ static int dev_wait(struct dm_ioctl *param, size_t param_size)
 	return r;
 }
 
+/*
+ * Remember the global event number and make it possible to poll
+ * for further events.
+ */
+static int dev_arm_poll(struct file *filp, struct dm_ioctl *param, size_t param_size)
+{
+	struct dm_file *priv = filp->private_data;
+
+	priv->global_event_nr = atomic_read(&dm_global_event_nr);
+
+	return 0;
+}
+
 static inline fmode_t get_mode(struct dm_ioctl *param)
 {
 	fmode_t mode = FMODE_READ | FMODE_WRITE;
@@ -1277,7 +1290,7 @@ static bool is_valid_type(enum dm_queue_mode cur, enum dm_queue_mode new)
 	return false;
 }
 
-static int table_load(struct dm_ioctl *param, size_t param_size)
+static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	int r;
 	struct hash_cell *hc;
@@ -1364,7 +1377,7 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
 	return r;
 }
 
-static int table_clear(struct dm_ioctl *param, size_t param_size)
+static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	struct hash_cell *hc;
 	struct mapped_device *md;
@@ -1438,7 +1451,7 @@ static void retrieve_deps(struct dm_table *table,
 	param->data_size = param->data_start + needed;
 }
 
-static int table_deps(struct dm_ioctl *param, size_t param_size)
+static int table_deps(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	struct mapped_device *md;
 	struct dm_table *table;
@@ -1464,7 +1477,7 @@ static int table_deps(struct dm_ioctl *param, size_t param_size)
  * Return the status of a device as a text string for each
  * target.
  */
-static int table_status(struct dm_ioctl *param, size_t param_size)
+static int table_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	struct mapped_device *md;
 	struct dm_table *table;
@@ -1519,7 +1532,7 @@ static int message_for_md(struct mapped_device *md, unsigned argc, char **argv,
 /*
  * Pass a message to the target that's at the supplied device offset.
  */
-static int target_message(struct dm_ioctl *param, size_t param_size)
+static int target_message(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	int r, argc;
 	char **argv;
@@ -1636,7 +1649,8 @@ static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
 		{DM_LIST_VERSIONS_CMD, 0, list_versions},
 
 		{DM_TARGET_MSG_CMD, 0, target_message},
-		{DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry}
+		{DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry},
+		{DM_DEV_ARM_POLL, IOCTL_FLAGS_NO_PARAMS, dev_arm_poll},
 	};
 
 	if (unlikely(cmd >= ARRAY_SIZE(_ioctls)))
@@ -1791,7 +1805,7 @@ static int validate_params(uint cmd, struct dm_ioctl *param)
 	return 0;
 }
 
-static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
+static int ctl_ioctl(struct file *file, uint command, struct dm_ioctl __user *user)
 {
 	int r = 0;
 	int ioctl_flags;
@@ -1845,7 +1859,7 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
 		goto out;
 
 	param->data_size = offsetof(struct dm_ioctl, data);
-	r = fn(param, input_param_size);
+	r = fn(file, param, input_param_size);
 
 	if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) &&
 	    unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS))
@@ -1864,7 +1878,7 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
 
 static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
 {
-	return (long)ctl_ioctl(command, (struct dm_ioctl __user *)u);
+	return (long)ctl_ioctl(file, command, (struct dm_ioctl __user *)u);
 }
 
 #ifdef CONFIG_COMPAT
diff --git a/include/uapi/linux/dm-ioctl.h b/include/uapi/linux/dm-ioctl.h
index 2f6c77aebe1a73d04b56611152244af00a14fdb0..412c06a624c83674e02f1d6669c4201d2a6c6e1b 100644
--- a/include/uapi/linux/dm-ioctl.h
+++ b/include/uapi/linux/dm-ioctl.h
@@ -240,7 +240,8 @@ enum {
 	/* Added later */
 	DM_LIST_VERSIONS_CMD,
 	DM_TARGET_MSG_CMD,
-	DM_DEV_SET_GEOMETRY_CMD
+	DM_DEV_SET_GEOMETRY_CMD,
+	DM_DEV_ARM_POLL_CMD,
 };
 
 #define DM_IOCTL 0xfd
@@ -255,6 +256,7 @@ enum {
 #define DM_DEV_SUSPEND   _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl)
 #define DM_DEV_STATUS    _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl)
 #define DM_DEV_WAIT      _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl)
+#define DM_DEV_ARM_POLL  _IOWR(DM_IOCTL, DM_DEV_ARM_POLL_CMD, struct dm_ioctl)
 
 #define DM_TABLE_LOAD    _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl)
 #define DM_TABLE_CLEAR   _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl)