include/linux/signalfd.h

   1 /*
   2  *  include/linux/signalfd.h
   3  *
   4  *  Copyright (C) 2007  Davide Libenzi <davidel@xmailserver.org>
   5  *
   6  */
   7
   8 #ifndef _LINUX_SIGNALFD_H
   9 #define _LINUX_SIGNALFD_H
  10
  11
  12 struct signalfd_siginfo {
  13         __u32 signo;
  14         __s32 err;
  15         __s32 code;
  16         __u32 pid;
  17         __u32 uid;
  18         __s32 fd;
  19         __u32 tid;
  20         __u32 band;
  21         __u32 overrun;
  22         __u32 trapno;
  23         __s32 status;
  24         __s32 svint;
  25         __u64 svptr;
  26         __u64 utime;
  27         __u64 stime;
  28         __u64 addr;
  29
  30         /*
  31          * Pad strcture to 128 bytes. Remember to update the
  32          * pad size when you add new memebers. We use a fixed
  33          * size structure to avoid compatibility problems with
  34          * future versions, and we leave extra space for additional
  35          * members. We use fixed size members because this strcture
  36          * comes out of a read(2) and we really don't want to have
  37          * a compat on read(2).
  38          */
  39         __u8 __pad[48];
  40 };
  41
  42
  43 #ifdef __KERNEL__
  44
  45 #ifdef CONFIG_SIGNALFD
  46
  47 /*
  48  * Deliver the signal to listening signalfd. This must be called
  49  * with the sighand lock held. Same are the following that end up
  50  * calling signalfd_deliver().
  51  */
  52 void signalfd_deliver(struct task_struct *tsk, int sig);
  53
  54 /*
  55  * No need to fall inside signalfd_deliver() if no signal listeners
  56  * are available.
  57  */
  58 static inline void signalfd_notify(struct task_struct *tsk, int sig)
  59 {
  60         if (unlikely(!list_empty(&tsk->sighand->signalfd_list)))
  61                 signalfd_deliver(tsk, sig);
  62 }
  63
  64 /*
  65  * The signal -1 is used to notify the signalfd that the sighand
  66  * is on its way to be detached.
  67  */
  68 static inline void signalfd_detach_locked(struct task_struct *tsk)
  69 {
  70         if (unlikely(!list_empty(&tsk->sighand->signalfd_list)))
  71                 signalfd_deliver(tsk, -1);
  72 }
  73
  74 static inline void signalfd_detach(struct task_struct *tsk)
  75 {
  76         struct sighand_struct *sighand = tsk->sighand;
  77
  78         if (unlikely(!list_empty(&sighand->signalfd_list))) {
  79                 spin_lock_irq(&sighand->siglock);
  80                 signalfd_deliver(tsk, -1);
  81                 spin_unlock_irq(&sighand->siglock);
  82         }
  83 }
  84
  85 #else /* CONFIG_SIGNALFD */
  86
  87 #define signalfd_deliver(t, s) do { } while (0)
  88 #define signalfd_notify(t, s) do { } while (0)
  89 #define signalfd_detach_locked(t) do { } while (0)
  90 #define signalfd_detach(t) do { } while (0)
  91
  92 #endif /* CONFIG_SIGNALFD */
  93
  94 #endif /* __KERNEL__ */
  95
  96 #endif /* _LINUX_SIGNALFD_H */
  97