kernel/vserver/helper.c

   1 /*
   2  *  linux/kernel/vserver/helper.c
   3  *
   4  *  Virtual Context Support
   5  *
   6  *  Copyright (C) 2004-2005  Herbert Pötzl
   7  *
   8  *  V0.01  basic helper
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/errno.h>
  14 #include <linux/reboot.h>
  15 #include <linux/kmod.h>
  16 #include <linux/sched.h>
  17 #include <linux/vs_context.h>
  18
  19 #include <asm/uaccess.h>
  20 #include <asm/unistd.h>
  21
  22
  23 char vshelper_path[255] = "/sbin/vshelper";
  24
  25
  26 /*
  27  *      vshelper path is set via /proc/sys
  28  *      invoked by vserver sys_reboot(), with
  29  *      the following arguments
  30  *
  31  *      argv [0] = vshelper_path;
  32  *      argv [1] = action: "restart", "halt", "poweroff", ...
  33  *      argv [2] = context identifier
  34  *
  35  *      envp [*] = type-specific parameters
  36  */
  37
  38 long vs_reboot(unsigned int cmd, void * arg)
  39 {
  40         char id_buf[8], cmd_buf[16];
  41         char uid_buf[16], pid_buf[16];
  42
  43         char *argv[] = {vshelper_path, NULL, id_buf, 0};
  44         char *envp[] = {"HOME=/", "TERM=linux",
  45                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
  46                         uid_buf, pid_buf, cmd_buf, 0};
  47
  48         snprintf(id_buf, sizeof(id_buf)-1, "%d", vx_current_xid());
  49
  50         snprintf(cmd_buf, sizeof(cmd_buf)-1, "VS_CMD=%08x", cmd);
  51         snprintf(uid_buf, sizeof(uid_buf)-1, "VS_UID=%d", current->uid);
  52         snprintf(pid_buf, sizeof(pid_buf)-1, "VS_PID=%d", current->pid);
  53
  54         switch (cmd) {
  55         case LINUX_REBOOT_CMD_RESTART:
  56                 argv[1] = "restart";
  57                 break;
  58
  59         case LINUX_REBOOT_CMD_HALT:
  60                 argv[1] = "halt";
  61                 break;
  62
  63         case LINUX_REBOOT_CMD_POWER_OFF:
  64                 argv[1] = "poweroff";
  65                 break;
  66
  67         case LINUX_REBOOT_CMD_SW_SUSPEND:
  68                 argv[1] = "swsusp";
  69                 break;
  70
  71         default:
  72                 argv[1] = "restart2";
  73                 break;
  74         }
  75
  76         /* maybe we should wait ? */
  77         if (call_usermodehelper(*argv, argv, envp, 1)) {
  78                 printk( KERN_WARNING
  79                         "vs_reboot(): failed to exec (%s %s %s)\n",
  80                         vshelper_path, argv[1], argv[2]);
  81                 return -EPERM;
  82         }
  83         return 0;
  84 }
  85
  86 long vs_context_state(unsigned int cmd)
  87 {
  88         char id_buf[8], cmd_buf[32];
  89
  90         char *argv[] = {vshelper_path, NULL, id_buf, NULL, 0};
  91         char *envp[] = {"HOME=/", "TERM=linux",
  92                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin", cmd_buf, 0};
  93
  94         snprintf(id_buf, sizeof(id_buf)-1, "%d", vx_current_xid());
  95         snprintf(cmd_buf, sizeof(cmd_buf)-1, "VS_CMD=%08x", cmd);
  96
  97         switch (cmd) {
  98         case VS_CONTEXT_CREATED:
  99                 argv[1] = "startup";
 100                 break;
 101         case VS_CONTEXT_DESTROY:
 102                 argv[1] = "shutdown";
 103                 break;
 104         default:
 105                 return 0;
 106         }
 107
 108         if (call_usermodehelper(*argv, argv, envp, 1)) {
 109                 printk( KERN_WARNING
 110                         "vs_context_state(): failed to exec (%s %s %s %s)\n",
 111                         vshelper_path, argv[1], argv[2], argv[3]);
 112                 return 0;
 113         }
 114         return 0;
 115 }
 116