kernel/vserver/signal.c

   1 /*
   2  *  linux/kernel/vserver/signal.c
   3  *
   4  *  Virtual Server: Signal Support
   5  *
   6  *  Copyright (C) 2003-2004  Herbert Pötzl
   7  *
   8  *  V0.01  broken out from vcontext V0.05
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/sched.h>
  14
  15 #include <asm/errno.h>
  16 #include <asm/uaccess.h>
  17
  18 #include <linux/vs_base.h>
  19 #include <linux/vs_context.h>
  20 #include <linux/vserver/signal.h>
  21
  22
  23 int vc_ctx_kill(uint32_t id, void __user *data)
  24 {
  25         int retval, count=0;
  26         struct vcmd_ctx_kill_v0 vc_data;
  27         struct siginfo info;
  28         struct task_struct *p;
  29         struct vx_info *vxi;
  30
  31         if (!vx_check(0, VX_ADMIN))
  32                 return -ENOSYS;
  33         if (copy_from_user (&vc_data, data, sizeof(vc_data)))
  34                 return -EFAULT;
  35
  36         info.si_signo = vc_data.sig;
  37         info.si_errno = 0;
  38         info.si_code = SI_USER;
  39         info.si_pid = current->pid;
  40         info.si_uid = current->uid;
  41
  42         vxi = locate_vx_info(id);
  43         if (!vxi)
  44                 return -ESRCH;
  45
  46         retval = -ESRCH;
  47         read_lock(&tasklist_lock);
  48         switch (vc_data.pid) {
  49         case -1:
  50         case  0:
  51                 for_each_process(p) {
  52                         int err = 0;
  53
  54                         if (vx_task_xid(p) != id || p->pid <= 1 ||
  55                                 (vc_data.pid && vxi->vx_initpid == p->pid) ||
  56                                 !thread_group_leader(p))
  57                                 continue;
  58
  59                         err = send_sig_info(vc_data.sig, &info, p);
  60                         ++count;
  61                         if (err != -EPERM)
  62                                 retval = err;
  63                 }
  64                 break;
  65
  66         default:
  67         p = find_task_by_real_pid(vc_data.pid);
  68                 if (p) {
  69                         if (!thread_group_leader(p)) {
  70                                 struct task_struct *tg;
  71
  72                                 tg = find_task_by_real_pid(p->tgid);
  73                                 if (tg)
  74                                         p = tg;
  75                         }
  76                         if ((id == -1) || (vx_task_xid(p) == id))
  77                                 retval = send_sig_info(vc_data.sig, &info, p);
  78                 }
  79                 break;
  80         }
  81         read_unlock(&tasklist_lock);
  82         put_vx_info(vxi);
  83         return retval;
  84 }
  85
  86
  87 static int __wait_exit(struct vx_info *vxi)
  88 {
  89         DECLARE_WAITQUEUE(wait, current);
  90         int ret = 0;
  91
  92         add_wait_queue(&vxi->vx_exit, &wait);
  93         set_current_state(TASK_INTERRUPTIBLE);
  94
  95 wait:
  96         if (vx_info_state(vxi, VXS_DEFUNCT))
  97                 goto out;
  98         if (signal_pending(current)) {
  99                 ret = -ERESTARTSYS;
 100                 goto out;
 101         }
 102         schedule();
 103         goto wait;
 104
 105 out:
 106         set_current_state(TASK_RUNNING);
 107         remove_wait_queue(&vxi->vx_exit, &wait);
 108         return ret;
 109 }
 110
 111
 112
 113 int vc_wait_exit(uint32_t id, void __user *data)
 114 {
 115 //      struct vcmd_wait_exit_v0 vc_data;
 116         struct vx_info *vxi;
 117         int ret;
 118
 119         vxi = locate_vx_info(id);
 120         if (!vxi)
 121                 return -ESRCH;
 122
 123         ret = __wait_exit(vxi);
 124         put_vx_info(vxi);
 125         return ret;
 126 }
 127