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("expect: %s load <module>", argv[0]);
  33                 return EXIT_FAILURE;
  34         }
  35
  36         for (i = 2; argv[i]; i++) {
  37                 log_debug("Execute '%s' '%s'", argv[1], argv[i]);
  38                 (void) module_load_and_warn(ctx, argv[i], false);
  39         }
  40
  41         return EXIT_SUCCESS;
  42 }
  43
  44 /* called at udev startup and reload */
  45 static int builtin_kmod_init(struct udev *udev) {
  46         if (ctx)
  47                 return 0;
  48
  49         ctx = kmod_new(NULL, NULL);
  50         if (!ctx)
  51                 return -ENOMEM;
  52
  53         log_debug("Load module index");
  54         kmod_set_log_fn(ctx, udev_kmod_log, udev);
  55         kmod_load_resources(ctx);
  56         return 0;
  57 }
  58
  59 /* called on udev shutdown and reload request */
  60 static void builtin_kmod_exit(struct udev *udev) {
  61         log_debug("Unload module index");
  62         ctx = kmod_unref(ctx);
  63 }
  64
  65 /* called every couple of seconds during event activity; 'true' if config has changed */
  66 static bool builtin_kmod_validate(struct udev *udev) {
  67         log_debug("Validate module index");
  68         if (!ctx)
  69                 return false;
  70         return (kmod_validate_resources(ctx) != KMOD_RESOURCES_OK);
  71 }
  72
  73 const struct udev_builtin udev_builtin_kmod = {
  74         .name = "kmod",
  75         .cmd = builtin_kmod,
  76         .init = builtin_kmod_init,
  77         .exit = builtin_kmod_exit,
  78         .validate = builtin_kmod_validate,
  79         .help = "Kernel module loader",
  80         .run_once = false,
  81 };