int btrfs_subvol_make_fd(int fd, const char *subvolume) {
struct btrfs_ioctl_vol_args args = {};
+ _cleanup_close_ int real_fd = -1;
int r;
assert(subvolume);
if (r < 0)
return r;
+ r = fcntl(fd, F_GETFL);
+ if (r < 0)
+ return -errno;
+ if (FLAGS_SET(r, O_PATH)) {
+ /* An O_PATH fd was specified, let's convert here to a proper one, as btrfs ioctl's can't deal with
+ * O_PATH. */
+
+ real_fd = fd_reopen(fd, O_RDONLY|O_CLOEXEC|O_DIRECTORY);
+ if (real_fd < 0)
+ return real_fd;
+
+ fd = real_fd;
+ }
+
strncpy(args.name, subvolume, sizeof(args.name)-1);
if (ioctl(fd, BTRFS_IOC_SUBVOL_CREATE, &args) < 0)