diff options
Diffstat (limited to 'arch/ia64/kernel/signal.c')
-rw-r--r-- | arch/ia64/kernel/signal.c | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c index 463f6bb44d07..1d7903ee2126 100644 --- a/arch/ia64/kernel/signal.c +++ b/arch/ia64/kernel/signal.c | |||
@@ -588,104 +588,3 @@ ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall) | |||
588 | } | 588 | } |
589 | return 0; | 589 | return 0; |
590 | } | 590 | } |
591 | |||
592 | /* Set a delayed signal that was detected in MCA/INIT/NMI/PMI context where it | ||
593 | * could not be delivered. It is important that the target process is not | ||
594 | * allowed to do any more work in user space. Possible cases for the target | ||
595 | * process: | ||
596 | * | ||
597 | * - It is sleeping and will wake up soon. Store the data in the current task, | ||
598 | * the signal will be sent when the current task returns from the next | ||
599 | * interrupt. | ||
600 | * | ||
601 | * - It is running in user context. Store the data in the current task, the | ||
602 | * signal will be sent when the current task returns from the next interrupt. | ||
603 | * | ||
604 | * - It is running in kernel context on this or another cpu and will return to | ||
605 | * user context. Store the data in the target task, the signal will be sent | ||
606 | * to itself when the target task returns to user space. | ||
607 | * | ||
608 | * - It is running in kernel context on this cpu and will sleep before | ||
609 | * returning to user context. Because this is also the current task, the | ||
610 | * signal will not get delivered and the task could sleep indefinitely. | ||
611 | * Store the data in the idle task for this cpu, the signal will be sent | ||
612 | * after the idle task processes its next interrupt. | ||
613 | * | ||
614 | * To cover all cases, store the data in the target task, the current task and | ||
615 | * the idle task on this cpu. Whatever happens, the signal will be delivered | ||
616 | * to the target task before it can do any useful user space work. Multiple | ||
617 | * deliveries have no unwanted side effects. | ||
618 | * | ||
619 | * Note: This code is executed in MCA/INIT/NMI/PMI context, with interrupts | ||
620 | * disabled. It must not take any locks nor use kernel structures or services | ||
621 | * that require locks. | ||
622 | */ | ||
623 | |||
624 | /* To ensure that we get the right pid, check its start time. To avoid extra | ||
625 | * include files in thread_info.h, convert the task start_time to unsigned long, | ||
626 | * giving us a cycle time of > 580 years. | ||
627 | */ | ||
628 | static inline unsigned long | ||
629 | start_time_ul(const struct task_struct *t) | ||
630 | { | ||
631 | return t->start_time.tv_sec * NSEC_PER_SEC + t->start_time.tv_nsec; | ||
632 | } | ||
633 | |||
634 | void | ||
635 | set_sigdelayed(pid_t pid, int signo, int code, void __user *addr) | ||
636 | { | ||
637 | struct task_struct *t; | ||
638 | unsigned long start_time = 0; | ||
639 | int i; | ||
640 | |||
641 | for (i = 1; i <= 3; ++i) { | ||
642 | switch (i) { | ||
643 | case 1: | ||
644 | t = find_task_by_pid(pid); | ||
645 | if (t) | ||
646 | start_time = start_time_ul(t); | ||
647 | break; | ||
648 | case 2: | ||
649 | t = current; | ||
650 | break; | ||
651 | default: | ||
652 | t = idle_task(smp_processor_id()); | ||
653 | break; | ||
654 | } | ||
655 | |||
656 | if (!t) | ||
657 | return; | ||
658 | task_thread_info(t)->sigdelayed.signo = signo; | ||
659 | task_thread_info(t)->sigdelayed.code = code; | ||
660 | task_thread_info(t)->sigdelayed.addr = addr; | ||
661 | task_thread_info(t)->sigdelayed.start_time = start_time; | ||
662 | task_thread_info(t)->sigdelayed.pid = pid; | ||
663 | wmb(); | ||
664 | set_tsk_thread_flag(t, TIF_SIGDELAYED); | ||
665 | } | ||
666 | } | ||
667 | |||
668 | /* Called from entry.S when it detects TIF_SIGDELAYED, a delayed signal that | ||
669 | * was detected in MCA/INIT/NMI/PMI context where it could not be delivered. | ||
670 | */ | ||
671 | |||
672 | void | ||
673 | do_sigdelayed(void) | ||
674 | { | ||
675 | struct siginfo siginfo; | ||
676 | pid_t pid; | ||
677 | struct task_struct *t; | ||
678 | |||
679 | clear_thread_flag(TIF_SIGDELAYED); | ||
680 | memset(&siginfo, 0, sizeof(siginfo)); | ||
681 | siginfo.si_signo = current_thread_info()->sigdelayed.signo; | ||
682 | siginfo.si_code = current_thread_info()->sigdelayed.code; | ||
683 | siginfo.si_addr = current_thread_info()->sigdelayed.addr; | ||
684 | pid = current_thread_info()->sigdelayed.pid; | ||
685 | t = find_task_by_pid(pid); | ||
686 | if (!t) | ||
687 | return; | ||
688 | if (current_thread_info()->sigdelayed.start_time != start_time_ul(t)) | ||
689 | return; | ||
690 | force_sig_info(siginfo.si_signo, &siginfo, t); | ||
691 | } | ||