src/udev/udev-builtin-kmod.c

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * load kernel modules
   4  *
   5  * Copyright © 2011 ProFUSION embedded systems
   6  *
   7  */
   8
   9 #include <errno.h>
  10 #include <libkmod.h>
  11 #include <stdarg.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14
  15 #include "module-util.h"
  16 #include "string-util.h"
  17 #include "udev.h"
  18
  19 static struct kmod_ctx *ctx = NULL;
  20
  21 _printf_(6,0) static void udev_kmod_log(void *data, int priority, const char *file, int line, const char *fn, const char *format, va_list args) {
  22         log_internalv(priority, 0, file, line, fn, format, args);
  23 }
  24
  25 static int builtin_kmod(struct udev_device *dev, int argc, char *argv[], bool test) {
  26         int i;
  27
  28         if (!ctx)
  29                 return 0;
  30
  31         if (argc < 3 || !streq(argv[1], "load")) {
  32                 log_error("%s: expected: load <module>", argv[0]);
  33                 return EXIT_FAILURE;
  34         }
  35
  36         for (i = 2; argv[i]; i++)
  37                 (void) module_load_and_warn(ctx, argv[i], false);
  38
  39         return EXIT_SUCCESS;
  40 }
  41
  42 /* called at udev startup and reload */
  43 static int builtin_kmod_init(struct udev *udev) {
  44         if (ctx)
  45                 return 0;
  46
  47         ctx = kmod_new(NULL, NULL);
  48         if (!ctx)
  49                 return -ENOMEM;
  50
  51         log_debug("Load module index");
  52         kmod_set_log_fn(ctx, udev_kmod_log, udev);
  53         kmod_load_resources(ctx);
  54         return 0;
  55 }
  56
  57 /* called on udev shutdown and reload request */
  58 static void builtin_kmod_exit(struct udev *udev) {
  59         log_debug("Unload module index");
  60         ctx = kmod_unref(ctx);
  61 }
  62
  63 /* called every couple of seconds during event activity; 'true' if config has changed */
  64 static bool builtin_kmod_validate(struct udev *udev) {
  65         log_debug("Validate module index");
  66         if (!ctx)
  67                 return false;
  68         return (kmod_validate_resources(ctx) != KMOD_RESOURCES_OK);
  69 }
  70
  71 const struct udev_builtin udev_builtin_kmod = {
  72         .name = "kmod",
  73         .cmd = builtin_kmod,
  74         .init = builtin_kmod_init,
  75         .exit = builtin_kmod_exit,
  76         .validate = builtin_kmod_validate,
  77         .help = "Kernel module loader",
  78         .run_once = false,
  79 };