btrfs-progs: use btrfs_open_dir for btrfs device command

We can use btrfs_open_dir() to check whether the target dir is
under btrfs mount point before openning, instead of checking it in kernel
through ioctl, and returning a  fuzzy error message.

Before patch:
  # (/mnt/tmp is not btrfs mountpoint)
  #
  # btrfs device add -f /dev/sda13 /mnt/tmp
  ERROR: error adding the device '/dev/sda13' - Inappropriate ioctl for device
  #

After patch:
  # btrfs device add -f /dev/sda13 /mnt/tmp
  ERROR: not btrfs filesystem: /mnt/tmp
  #

Similar fix for device remove and device usage.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
[renamed to btrfs_open_dir]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/cmds-device.c b/cmds-device.c
index 8e69b88..844289a 100644 (file)
--- a/cmds-device.c
+++ b/cmds-device.c
@@ -84,11 +84,9 @@ static int cmd_device_add(int argc, char **argv)
 
        mntpnt = argv[optind + argc - 1];
 
-       fdmnt = open_file_or_dir(mntpnt, &dirstream);
-       if (fdmnt < 0) {
-               fprintf(stderr, "ERROR: can't access '%s'\n", mntpnt);
+       fdmnt = btrfs_open_dir(mntpnt, &dirstream, 1);
+       if (fdmnt < 0)
                return 1;
-       }
 
        for (i = optind; i < optind + argc - 1; i++){
                struct btrfs_ioctl_vol_args ioctl_args;
@@ -157,11 +155,9 @@ static int _cmd_device_remove(int argc, char **argv,
 
        mntpnt = argv[argc - 1];
 
-       fdmnt = open_file_or_dir(mntpnt, &dirstream);
-       if (fdmnt < 0) {
-               fprintf(stderr, "ERROR: can't access '%s'\n", mntpnt);
+       fdmnt = btrfs_open_dir(mntpnt, &dirstream, 1);
+       if (fdmnt < 0)
                return 1;
-       }
 
        for(i=1 ; i < argc - 1; i++ ){
                struct  btrfs_ioctl_vol_args arg;
@@ -588,10 +584,8 @@ int cmd_device_usage(int argc, char **argv)
                if (more_than_one)
                        printf("\n");
 
-               fd = open_file_or_dir(argv[i], &dirstream);
+               fd = btrfs_open_dir(argv[i], &dirstream, 1);
                if (fd < 0) {
-                       fprintf(stderr, "ERROR: can't access '%s'\n",
-                               argv[1]);
                        ret = 1;
                        goto out;
                }