[PATCH] Btrfs-progs: add sanity checks for btrfs device operations

[Wang Shilong <wangsl.fnst@cn.fujitsu.com>]

Make sure we are a block device firstly, this can avoid some
unnecessary ioctls operations.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
---
 cmds-device.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/cmds-device.c b/cmds-device.c
index bc4a8dc..ea20919 100644
--- a/cmds-device.c
+++ b/cmds-device.c
@@ -161,6 +161,12 @@ static int cmd_rm_dev(int argc, char **argv)
 		struct	btrfs_ioctl_vol_args arg;
 		int	res;
 
+		if (!is_block_device(argv[i])) {
+			fprintf(stderr,
+				"ERROR: %s is not a block device\n", argv[i]);
+			ret++;
+			continue;
+		}
 		strncpy_null(arg.name, argv[i]);
 		res = ioctl(fdmnt, BTRFS_IOC_RM_DEV, &arg);
 		e = errno;
@@ -222,6 +228,12 @@ static int cmd_scan_dev(int argc, char **argv)
 		struct btrfs_ioctl_vol_args args;
 		int ret;
 
+		if (!is_block_device(argv[i])) {
+			fprintf(stderr,
+				"ERROR: %s is not a block device\n", argv[i]);
+			close(fd);
+			return 1;
+		}
 		printf("Scanning for Btrfs filesystems in '%s'\n", argv[i]);
 
 		strncpy_null(args.name, argv[i]);
@@ -265,6 +277,12 @@ static int cmd_ready_dev(int argc, char **argv)
 		perror("failed to open /dev/btrfs-control");
 		return 1;
 	}
+	if (!is_block_device(argv[1])) {
+		fprintf(stderr,
+			"ERROR: %s is not a block device\n", argv[1]);
+		close(fd);
+		return 1;
+	}
 
 	strncpy(args.name, argv[argc - 1], BTRFS_PATH_NAME_MAX);
 	ret = ioctl(fd, BTRFS_IOC_DEVICES_READY, &args);
-- 
1.8.3.1