src/kmod-setup.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <sys/wait.h>
  23 #include <unistd.h>
  24 #include <string.h>
  25 #include <errno.h>
  26
  27 #include "macro.h"
  28 #include "execute.h"
  29
  30 #include "kmod-setup.h"
  31
  32 static const char * const kmod_table[] = {
  33         "autofs4", "/sys/class/misc/autofs",
  34         "ipv6",    "/sys/module/ipv6"
  35 };
  36
  37 int kmod_setup(void) {
  38         unsigned i, n = 0;
  39         const char * cmdline[3 + ELEMENTSOF(kmod_table) + 1];
  40         ExecCommand command;
  41         ExecContext context;
  42         pid_t pid;
  43         int status, r;
  44
  45         for (i = 0; i < ELEMENTSOF(kmod_table); i += 2) {
  46
  47                 if (access(kmod_table[i+1], F_OK) >= 0)
  48                         continue;
  49
  50                 log_info("Your kernel apparently lacks built-in %s support. Please fix that. "
  51                          "We'll now try to work around this by calling '/sbin/modprobe %s'...",
  52                          kmod_table[i], kmod_table[i]);
  53
  54                 cmdline[3 + n++] = kmod_table[i];
  55         }
  56
  57         if (n <= 0)
  58                 return 0;
  59
  60         cmdline[0] = "/sbin/modprobe";
  61         cmdline[1] = "-qab";
  62         cmdline[2] = "--";
  63         cmdline[3 + n] = NULL;
  64
  65         zero(command);
  66         zero(context);
  67
  68         command.path = (char*) cmdline[0];
  69         command.argv = (char**) cmdline;
  70
  71         exec_context_init(&context);
  72         r = exec_spawn(&command, NULL, &context, NULL, 0, NULL, false, false, false, NULL, &pid);
  73         exec_context_done(&context);
  74
  75         if (r < 0)
  76                 return r;
  77
  78         for (;;) {
  79                 if (waitpid(pid, &status, 0) < 0) {
  80
  81                         if (errno == EINTR)
  82                                 continue;
  83
  84                         return -errno;
  85                 }
  86
  87                 break;
  88         }
  89
  90         if (WIFEXITED(status)) {
  91                 if (WEXITSTATUS(status) != 0) {
  92                         log_warning("/sbin/modprobe failed with error code %i.", WEXITSTATUS(status));
  93                         return -EPROTO;
  94                 }
  95
  96                 log_debug("/sbin/modprobe succeeded.");
  97                 return 0;
  98         }
  99
 100         if (WIFSIGNALED(status)) {
 101                 log_warning("/sbin/modprobe terminated by signal %s.", strsignal(WTERMSIG(status)));
 102                 return -EPROTO;
 103         }
 104
 105         log_warning("/sbin/modprobe failed due to unknown reason.");
 106         return -EPROTO;
 107 }