src/udev/udev-builtin-btrfs.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2012 Kay Sievers <kay@vrfy.org>
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <unistd.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <stdio.h>
  24 #include <fcntl.h>
  25 #include <errno.h>
  26 #include <sys/ioctl.h>
  27
  28 #include "udev.h"
  29
  30 #define BTRFS_PATH_NAME_MAX 4087
  31 struct btrfs_ioctl_vol_args {
  32         int64_t fd;
  33         char name[BTRFS_PATH_NAME_MAX + 1];
  34 };
  35 #define BTRFS_IOCTL_MAGIC 0x94
  36 #define BTRFS_IOC_DEVICES_READY _IOR(BTRFS_IOCTL_MAGIC, 39, struct btrfs_ioctl_vol_args)
  37
  38 static int builtin_btrfs(struct udev_device *dev, int argc, char *argv[], bool test)
  39 {
  40         struct  btrfs_ioctl_vol_args args;
  41         _cleanup_close_ int fd = -1;
  42         int err;
  43
  44         if (argc != 3 || !streq(argv[1], "ready"))
  45                 return EXIT_FAILURE;
  46
  47         fd = open("/dev/btrfs-control", O_RDWR|O_CLOEXEC);
  48         if (fd < 0)
  49                 return EXIT_FAILURE;
  50
  51         strscpy(args.name, sizeof(args.name), argv[2]);
  52         err = ioctl(fd, BTRFS_IOC_DEVICES_READY, &args);
  53         if (err < 0)
  54                 return EXIT_FAILURE;
  55
  56         udev_builtin_add_property(dev, test, "ID_BTRFS_READY", err == 0 ? "1" : "0");
  57         return EXIT_SUCCESS;
  58 }
  59
  60 const struct udev_builtin udev_builtin_btrfs = {
  61         .name = "btrfs",
  62         .cmd = builtin_btrfs,
  63         .help = "btrfs volume management",
  64 };