src/udev/udev-builtin-kmod.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /*
   4  * load kernel modules
   5  *
   6  * Copyright (C) 2011-2012 Kay Sievers <kay@vrfy.org>
   7  * Copyright (C) 2011 ProFUSION embedded systems
   8  *
   9  * This program is free software: you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation, either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23 #include <errno.h>
  24 #include <libkmod.h>
  25 #include <stdarg.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28
  29 #include "string-util.h"
  30 #include "udev.h"
  31
  32 static struct kmod_ctx *ctx = NULL;
  33
  34 static int load_module(struct udev *udev, const char *alias) {
  35         struct kmod_list *list = NULL;
  36         struct kmod_list *l;
  37         int err;
  38
  39         err = kmod_module_new_from_lookup(ctx, alias, &list);
  40         if (err < 0)
  41                 return err;
  42
  43         if (list == NULL)
  44                 log_debug("No module matches '%s'", alias);
  45
  46         kmod_list_foreach(l, list) {
  47                 struct kmod_module *mod = kmod_module_get_module(l);
  48
  49                 err = kmod_module_probe_insert_module(mod, KMOD_PROBE_APPLY_BLACKLIST, NULL, NULL, NULL, NULL);
  50                 if (err == KMOD_PROBE_APPLY_BLACKLIST)
  51                         log_debug("Module '%s' is blacklisted", kmod_module_get_name(mod));
  52                 else if (err == 0)
  53                         log_debug("Inserted '%s'", kmod_module_get_name(mod));
  54                 else
  55                         log_debug("Failed to insert '%s'", kmod_module_get_name(mod));
  56
  57                 kmod_module_unref(mod);
  58         }
  59
  60         kmod_module_unref_list(list);
  61         return err;
  62 }
  63
  64 _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) {
  65         log_internalv(priority, 0, file, line, fn, format, args);
  66 }
  67
  68 static int builtin_kmod(struct udev_device *dev, int argc, char *argv[], bool test) {
  69         struct udev *udev = udev_device_get_udev(dev);
  70         int i;
  71
  72         if (!ctx)
  73                 return 0;
  74
  75         if (argc < 3 || !streq(argv[1], "load")) {
  76                 log_error("expect: %s load <module>", argv[0]);
  77                 return EXIT_FAILURE;
  78         }
  79
  80         for (i = 2; argv[i]; i++) {
  81                 log_debug("Execute '%s' '%s'", argv[1], argv[i]);
  82                 load_module(udev, argv[i]);
  83         }
  84
  85         return EXIT_SUCCESS;
  86 }
  87
  88 /* called at udev startup and reload */
  89 static int builtin_kmod_init(struct udev *udev) {
  90         if (ctx)
  91                 return 0;
  92
  93         ctx = kmod_new(NULL, NULL);
  94         if (!ctx)
  95                 return -ENOMEM;
  96
  97         log_debug("Load module index");
  98         kmod_set_log_fn(ctx, udev_kmod_log, udev);
  99         kmod_load_resources(ctx);
 100         return 0;
 101 }
 102
 103 /* called on udev shutdown and reload request */
 104 static void builtin_kmod_exit(struct udev *udev) {
 105         log_debug("Unload module index");
 106         ctx = kmod_unref(ctx);
 107 }
 108
 109 /* called every couple of seconds during event activity; 'true' if config has changed */
 110 static bool builtin_kmod_validate(struct udev *udev) {
 111         log_debug("Validate module index");
 112         if (!ctx)
 113                 return false;
 114         return (kmod_validate_resources(ctx) != KMOD_RESOURCES_OK);
 115 }
 116
 117 const struct udev_builtin udev_builtin_kmod = {
 118         .name = "kmod",
 119         .cmd = builtin_kmod,
 120         .init = builtin_kmod_init,
 121         .exit = builtin_kmod_exit,
 122         .validate = builtin_kmod_validate,
 123         .help = "Kernel module loader",
 124         .run_once = false,
 125 };