From 2fc10620e741153329e2f1cbcde76e526f501410 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Wed, 18 Jan 2006 17:44:02 -0800 Subject: [PATCH] uml: add TIF_RESTORE_SIGMASK support Add support for TIF_RESTORE_SIGMASK. I copy the i386 handling of the flag. sys_sigsuspend is also changed to follow i386. Also a bit of cleanup - turn an if into a switch get rid of a couple more emacs formatting comments Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/kernel/signal_kern.c | 79 +++++++++++++++++++++++--------------------- 1 file changed, 41 insertions(+), 38 deletions(-) (limited to 'arch/um/kernel') diff --git a/arch/um/kernel/signal_kern.c b/arch/um/kernel/signal_kern.c index 7b0e0e81c16..7a54708db50 100644 --- a/arch/um/kernel/signal_kern.c +++ b/arch/um/kernel/signal_kern.c @@ -99,31 +99,46 @@ static int handle_signal(struct pt_regs *regs, unsigned long signr, return err; } -static int kern_do_signal(struct pt_regs *regs, sigset_t *oldset) +static int kern_do_signal(struct pt_regs *regs) { struct k_sigaction ka_copy; siginfo_t info; + sigset_t *oldset; int sig, handled_sig = 0; + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + oldset = ¤t->saved_sigmask; + else + oldset = ¤t->blocked; + while((sig = get_signal_to_deliver(&info, &ka_copy, regs, NULL)) > 0){ handled_sig = 1; /* Whee! Actually deliver the signal. */ - if(!handle_signal(regs, sig, &ka_copy, &info, oldset)) + if(!handle_signal(regs, sig, &ka_copy, &info, oldset)){ + /* a signal was successfully delivered; the saved + * sigmask will have been stored in the signal frame, + * and will be restored by sigreturn, so we can simply + * clear the TIF_RESTORE_SIGMASK flag */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + clear_thread_flag(TIF_RESTORE_SIGMASK); break; + } } /* Did we come from a system call? */ if(!handled_sig && (PT_REGS_SYSCALL_NR(regs) >= 0)){ /* Restart the system call - no handlers present */ - if(PT_REGS_SYSCALL_RET(regs) == -ERESTARTNOHAND || - PT_REGS_SYSCALL_RET(regs) == -ERESTARTSYS || - PT_REGS_SYSCALL_RET(regs) == -ERESTARTNOINTR){ + switch(PT_REGS_SYSCALL_RET(regs)){ + case -ERESTARTNOHAND: + case -ERESTARTSYS: + case -ERESTARTNOINTR: PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs); PT_REGS_RESTART_SYSCALL(regs); - } - else if(PT_REGS_SYSCALL_RET(regs) == -ERESTART_RESTARTBLOCK){ + break; + case -ERESTART_RESTARTBLOCK: PT_REGS_SYSCALL_RET(regs) = __NR_restart_syscall; PT_REGS_RESTART_SYSCALL(regs); + break; } } @@ -137,12 +152,19 @@ static int kern_do_signal(struct pt_regs *regs, sigset_t *oldset) if(current->ptrace & PT_DTRACE) current->thread.singlestep_syscall = is_syscall(PT_REGS_IP(¤t->thread.regs)); + + /* if there's no signal to deliver, we just put the saved sigmask + * back */ + if (!handled_sig && test_thread_flag(TIF_RESTORE_SIGMASK)) { + clear_thread_flag(TIF_RESTORE_SIGMASK); + sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); + } return(handled_sig); } int do_signal(void) { - return(kern_do_signal(¤t->thread.regs, ¤t->blocked)); + return(kern_do_signal(¤t->thread.regs)); } /* @@ -150,27 +172,22 @@ int do_signal(void) */ long sys_sigsuspend(int history0, int history1, old_sigset_t mask) { - sigset_t saveset; - mask &= _BLOCKABLE; spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; + current->saved_sigmask = current->blocked; siginitset(¤t->blocked, mask); recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - PT_REGS_SYSCALL_RET(¤t->thread.regs) = -EINTR; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - if(kern_do_signal(¤t->thread.regs, &saveset)) - return(-EINTR); - } + current->state = TASK_INTERRUPTIBLE; + schedule(); + set_thread_flag(TIF_RESTORE_SIGMASK); + return -ERESTARTNOHAND; } long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize) { - sigset_t saveset, newset; + sigset_t newset; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) @@ -181,32 +198,18 @@ long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize) sigdelsetmask(&newset, ~_BLOCKABLE); spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; + current->saved_sigmask = current->blocked; current->blocked = newset; recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - PT_REGS_SYSCALL_RET(¤t->thread.regs) = -EINTR; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - if (kern_do_signal(¤t->thread.regs, &saveset)) - return(-EINTR); - } + current->state = TASK_INTERRUPTIBLE; + schedule(); + set_thread_flag(TIF_RESTORE_SIGMASK); + return -ERESTARTNOHAND; } long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss) { return(do_sigaltstack(uss, uoss, PT_REGS_SP(¤t->thread.regs))); } - -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */ -- cgit v1.2.3