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/sched.h>
  13
  14 #include <asm/errno.h>
  15 #include <asm/uaccess.h>
  16
  17 #include <linux/vs_context.h>
  18 #include <linux/vserver/signal_cmd.h>
  19
  20
  21 int vx_info_kill(struct vx_info *vxi, int pid, int sig)
  22 {
  23         int retval, count=0;
  24         struct task_struct *p;
  25         unsigned long priv = 0;
  26
  27         retval = -ESRCH;
  28         vxdprintk(VXD_CBIT(misc, 4),
  29                 "vx_info_kill(%p[#%d],%d,%d)*",
  30                 vxi, vxi->vx_id, pid, sig);
  31         read_lock(&tasklist_lock);
  32         switch (pid) {
  33         case  0:
  34                 priv = 1;
  35         case -1:
  36                 for_each_process(p) {
  37                         int err = 0;
  38
  39                         if (vx_task_xid(p) != vxi->vx_id || p->pid <= 1 ||
  40                                 (pid && vxi->vx_initpid == p->pid))
  41                                 continue;
  42
  43                         err = group_send_sig_info(sig, (void*)priv, p);
  44                         ++count;
  45                         if (err != -EPERM)
  46                                 retval = err;
  47                 }
  48                 break;
  49
  50         case 1:
  51                 if (vxi->vx_initpid) {
  52                         pid = vxi->vx_initpid;
  53                         priv = 1;
  54                 }
  55                 /* fallthrough */
  56         default:
  57                 p = find_task_by_real_pid(pid);
  58                 if (p) {
  59                         if (vx_task_xid(p) == vxi->vx_id)
  60                                 retval = group_send_sig_info(sig,
  61                                         (void*)priv, p);
  62                 }
  63                 break;
  64         }
  65         read_unlock(&tasklist_lock);
  66         vxdprintk(VXD_CBIT(misc, 4),
  67                 "vx_info_kill(%p[#%d],%d,%d) = %d",
  68                 vxi, vxi->vx_id, pid, sig, retval);
  69         return retval;
  70 }
  71
  72 int vc_ctx_kill(uint32_t id, void __user *data)
  73 {
  74         int retval;
  75         struct vcmd_ctx_kill_v0 vc_data;
  76         struct vx_info *vxi;
  77
  78         if (!vx_check(0, VX_ADMIN))
  79                 return -ENOSYS;
  80         if (copy_from_user (&vc_data, data, sizeof(vc_data)))
  81                 return -EFAULT;
  82
  83         vxi = lookup_vx_info(id);
  84         if (!vxi)
  85                 return -ESRCH;
  86
  87         retval = vx_info_kill(vxi, vc_data.pid, vc_data.sig);
  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,
 103                 VXS_SHUTDOWN|VXS_HASHED|VXS_HELPER) == VXS_SHUTDOWN)
 104                 goto out;
 105         if (signal_pending(current)) {
 106                 ret = -ERESTARTSYS;
 107                 goto out;
 108         }
 109         schedule();
 110         goto wait;
 111
 112 out:
 113         set_current_state(TASK_RUNNING);
 114         remove_wait_queue(&vxi->vx_wait, &wait);
 115         return ret;
 116 }
 117
 118
 119
 120 int vc_wait_exit(uint32_t id, void __user *data)
 121 {
 122         struct vx_info *vxi;
 123         struct vcmd_wait_exit_v0 vc_data;
 124         int ret;
 125
 126         vxi = lookup_vx_info(id);
 127         if (!vxi)
 128                 return -ESRCH;
 129
 130         ret = __wait_exit(vxi);
 131         vc_data.reboot_cmd = vxi->reboot_cmd;
 132         vc_data.exit_code = vxi->exit_code;
 133         put_vx_info(vxi);
 134
 135         if (copy_to_user (data, &vc_data, sizeof(vc_data)))
 136                 ret = -EFAULT;
 137         return ret;
 138 }
 139