btrfs-progs: replace: use btrfs_open_dir for btrfs replace command

We can use btrfs_open_dir() to check whether target dir is
in btrfs's mount point before open, instead of checking it in
kernel space of ioctl, and return fuzzy error message.

Before patch:
  # ./btrfs replace cancel /mnt/tmp1
  ERROR: ioctl(DEV_REPLACE_CANCEL) failed on "/mnt/tmp1": Inappropriate ioctl for device
  # ./btrfs replace status /mnt/tmp1
  ERROR: ioctl(DEV_REPLACE_STATUS) failed on "/mnt/tmp1": Inappropriate ioctl for device

After patch:
  # ./btrfs replace cancel /mnt/tmp1
  ERROR: not a btrfs filesystem: /mnt/tmp1
  # ./btrfs replace status /mnt/tmp1
  ERROR: not a btrfs filesystem: /mnt/tmp1

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/cmds-replace.c b/cmds-replace.c
index 385b764..9596f2a 100644 (file)
--- a/cmds-replace.c
+++ b/cmds-replace.c
@@ -348,7 +348,6 @@ static const char *const cmd_replace_status_usage[] = {
 static int cmd_replace_status(int argc, char **argv)
 {
        int fd;
-       int e;
        int c;
        char *path;
        int once = 0;
@@ -370,13 +369,9 @@ static int cmd_replace_status(int argc, char **argv)
                usage(cmd_replace_status_usage);
 
        path = argv[optind];
-       fd = open_file_or_dir(path, &dirstream);
-       e = errno;
-       if (fd < 0) {
-               fprintf(stderr, "ERROR: can't access \"%s\": %s\n",
-                       path, strerror(e));
+       fd = btrfs_open_dir(path, &dirstream, 1);
+       if (fd < 0)
                return 1;
-       }
 
        ret = print_replace_status(fd, path, once);
        close_file_or_dir(fd, dirstream);
@@ -541,12 +536,9 @@ static int cmd_replace_cancel(int argc, char **argv)
                usage(cmd_replace_cancel_usage);
 
        path = argv[optind];
-       fd = open_file_or_dir(path, &dirstream);
-       if (fd < 0) {
-               fprintf(stderr, "ERROR: can't access \"%s\": %s\n",
-                       path, strerror(errno));
+       fd = btrfs_open_dir(path, &dirstream, 1);
+       if (fd < 0)
                return 1;
-       }
 
        args.cmd = BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL;
        args.result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_RESULT;