kernel/vserver/signal.c

   1 /*
   2  *  linux/kernel/vserver/signal.c
   3  *
   4  *  Virtual Server: Signal Support
   5  *
   6  *  Copyright (C) 2003-2005  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_context.h>
  19 #include <linux/vserver/signal_cmd.h>
  20
  21
  22 int vc_ctx_kill(uint32_t id, void __user *data)
  23 {
  24         int retval, count=0;
  25         struct vcmd_ctx_kill_v0 vc_data;
  26         struct siginfo info;
  27         struct task_struct *p;
  28         struct vx_info *vxi;
  29
  30         if (!vx_check(0, VX_ADMIN))
  31                 return -ENOSYS;
  32         if (copy_from_user (&vc_data, data, sizeof(vc_data)))
  33                 return -EFAULT;
  34
  35         info.si_signo = vc_data.sig;
  36         info.si_errno = 0;
  37         info.si_code = SI_USER;
  38         info.si_pid = current->pid;
  39         info.si_uid = current->uid;
  40
  41         vxi = locate_vx_info(id);
  42         if (!vxi)
  43                 return -ESRCH;
  44
  45         retval = -ESRCH;
  46         read_lock(&tasklist_lock);
  47         switch (vc_data.pid) {
  48         case  0:
  49                 info.si_code = SI_KERNEL;
  50         case -1:
  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         case 1:
  67                 if (vxi->vx_initpid) {
  68                         vc_data.pid = vxi->vx_initpid;
  69                         info.si_code = SI_KERNEL;
  70                 }
  71                 /* fallthrough */
  72         default:
  73                 p = find_task_by_real_pid(vc_data.pid);
  74                 if (p) {
  75                         if (!thread_group_leader(p)) {
  76                                 struct task_struct *tg;
  77
  78                                 tg = find_task_by_real_pid(p->tgid);
  79                                 if (tg)
  80                                         p = tg;
  81                         }
  82                         if ((id == -1) || (vx_task_xid(p) == id))
  83                                 retval = send_sig_info(vc_data.sig, &info, p);
  84                 }
  85                 break;
  86         }
  87         read_unlock(&tasklist_lock);
  88         put_vx_info(vxi);
  89         return retval;
  90 }
  91
  92
  93 static int __wait_exit(struct vx_info *vxi)
  94 {
  95         DECLARE_WAITQUEUE(wait, current);
  96         int ret = 0;
  97
  98         add_wait_queue(&vxi->vx_wait, &wait);
  99         set_current_state(TASK_INTERRUPTIBLE);
 100
 101 wait:
 102         if (vx_info_state(vxi, VXS_SHUTDOWN|VXS_HASHED) == VXS_SHUTDOWN)
 103                 goto out;
 104         if (signal_pending(current)) {
 105                 ret = -ERESTARTSYS;
 106                 goto out;
 107         }
 108         schedule();
 109         goto wait;
 110
 111 out:
 112         set_current_state(TASK_RUNNING);
 113         remove_wait_queue(&vxi->vx_wait, &wait);
 114         return ret;
 115 }
 116
 117
 118
 119 int vc_wait_exit(uint32_t id, void __user *data)
 120 {
 121 //      struct vcmd_wait_exit_v0 vc_data;
 122         struct vx_info *vxi;
 123         int ret;
 124
 125         vxi = locate_vx_info(id);
 126         if (!vxi)
 127                 return -ESRCH;
 128
 129         ret = __wait_exit(vxi);
 130         put_vx_info(vxi);
 131         return ret;
 132 }
 133