diff --git a/cmds-device.c b/cmds-device.c
index 4787aca1..75ee293d 100644
--- a/cmds-device.c
+++ b/cmds-device.c
@@ -250,11 +250,46 @@ static int cmd_scan_dev(int argc, char **argv)
 	return 0;
 }
 
+static const char * const cmd_ready_dev_usage[] = {
+	"btrfs device ready <device>",
+	"Check device to see if it has all of it's devices in cache for mounting",
+	NULL
+};
+
+static int cmd_ready_dev(int argc, char **argv)
+{
+	struct	btrfs_ioctl_vol_args args;
+	int	fd;
+	int	ret;
+
+	if (check_argc_min(argc, 2))
+		usage(cmd_ready_dev_usage);
+
+	fd = open("/dev/btrfs-control", O_RDWR);
+	if (fd < 0) {
+		perror("failed to open /dev/btrfs-control");
+		return 10;
+	}
+
+	strncpy(args.name, argv[argc - 1], BTRFS_PATH_NAME_MAX);
+	ret = ioctl(fd, BTRFS_IOC_DEVICES_READY, &args);
+	if (ret < 0) {
+		fprintf(stderr, "ERROR: unable to determine if the device '%s'"
+			" is ready for mounting - %s\n", argv[argc - 1],
+			strerror(errno));
+		ret = 1;
+	}
+
+	close(fd);
+	return ret;
+}
+
 const struct cmd_group device_cmd_group = {
 	device_cmd_group_usage, NULL, {
 		{ "add", cmd_add_dev, cmd_add_dev_usage, NULL, 0 },
 		{ "delete", cmd_rm_dev, cmd_rm_dev_usage, NULL, 0 },
 		{ "scan", cmd_scan_dev, cmd_scan_dev_usage, NULL, 0 },
+		{ "ready", cmd_ready_dev, cmd_ready_dev_usage, NULL, 0 },
 		{ 0, 0, 0, 0, 0 }
 	}
 };
diff --git a/ioctl.h b/ioctl.h
index 6fda3a1d..d32e22cb 100644
--- a/ioctl.h
+++ b/ioctl.h
@@ -419,6 +419,8 @@ struct btrfs_ioctl_clone_range_args {
 					struct btrfs_ioctl_ino_path_args)
 #define BTRFS_IOC_LOGICAL_INO _IOWR(BTRFS_IOCTL_MAGIC, 36, \
 					struct btrfs_ioctl_ino_path_args)
+#define BTRFS_IOC_DEVICES_READY _IOR(BTRFS_IOCTL_MAGIC, 39, \
+				     struct btrfs_ioctl_vol_args)
 
 #define BTRFS_IOC_SET_RECEIVED_SUBVOL _IOWR(BTRFS_IOCTL_MAGIC, 37, \
 				struct btrfs_ioctl_received_subvol_args)