X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fi386%2Fkernel%2Fsignal.c;h=9ffe9bf144af125e923586d1fe6405bb41d24b55;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=ea46d028af0872f5df65188503fcd9f71f3004e1;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git diff --git a/arch/i386/kernel/signal.c b/arch/i386/kernel/signal.c index ea46d028a..9ffe9bf14 100644 --- a/arch/i386/kernel/signal.c +++ b/arch/i386/kernel/signal.c @@ -37,51 +37,17 @@ asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask) { - struct pt_regs * regs = (struct pt_regs *) &history0; - 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); - regs->eax = -EINTR; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - if (do_signal(regs, &saveset)) - return -EINTR; - } -} - -asmlinkage int -sys_rt_sigsuspend(struct pt_regs regs) -{ - sigset_t saveset, newset; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (regs.ecx != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&newset, (sigset_t __user *)regs.ebx, sizeof(newset))) - return -EFAULT; - sigdelsetmask(&newset, ~_BLOCKABLE); - - spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; - current->blocked = newset; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - regs.eax = -EINTR; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - if (do_signal(®s, &saveset)) - return -EINTR; - } + current->state = TASK_INTERRUPTIBLE; + schedule(); + set_thread_flag(TIF_RESTORE_SIGMASK); + return -ERESTARTNOHAND; } asmlinkage int @@ -157,7 +123,8 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax err |= __get_user(tmp, &sc->seg); \ loadsegment(seg,tmp); } -#define FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | X86_EFLAGS_DF | \ +#define FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_RF | \ + X86_EFLAGS_OF | X86_EFLAGS_DF | \ X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \ X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF) @@ -278,9 +245,9 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate, int tmp, err = 0; tmp = 0; - __asm__("movl %%gs,%0" : "=r"(tmp): "0"(tmp)); + savesegment(gs, tmp); err |= __put_user(tmp, (unsigned int __user *)&sc->gs); - __asm__("movl %%fs,%0" : "=r"(tmp): "0"(tmp)); + savesegment(fs, tmp); err |= __put_user(tmp, (unsigned int __user *)&sc->fs); err |= __put_user(regs->xes, (unsigned int __user *)&sc->es); @@ -338,7 +305,11 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) esp = (unsigned long) ka->sa.sa_restorer; } - return (void __user *)((esp - frame_size) & -8ul); + esp -= frame_size; + /* Align the stack pointer according to the i386 ABI, + * i.e. so that on function entry ((sp + 4) & 15) == 0. */ + esp = ((esp + 4) & -16ul) - 4; + return (void __user *) esp; } /* These symbols are defined with the addresses in the vsyscall page. @@ -346,8 +317,8 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) extern void __user __kernel_sigreturn; extern void __user __kernel_rt_sigreturn; -static void setup_frame(int sig, struct k_sigaction *ka, - sigset_t *set, struct pt_regs * regs) +static int setup_frame(int sig, struct k_sigaction *ka, + sigset_t *set, struct pt_regs * regs) { void __user *restorer; struct sigframe __user *frame; @@ -380,7 +351,7 @@ static void setup_frame(int sig, struct k_sigaction *ka, goto give_sigsegv; } - restorer = &__kernel_sigreturn; + restorer = current->mm->context.vdso + (long)&__kernel_sigreturn; if (ka->sa.sa_flags & SA_RESTORER) restorer = ka->sa.sa_restorer; @@ -429,13 +400,14 @@ static void setup_frame(int sig, struct k_sigaction *ka, current->comm, current->pid, frame, regs->eip, frame->pretcode); #endif - return; + return 0; give_sigsegv: force_sigsegv(sig, current); + return -EFAULT; } -static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, +static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set, struct pt_regs * regs) { void __user *restorer; @@ -475,7 +447,7 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, goto give_sigsegv; /* Set up to return from userspace. */ - restorer = &__kernel_rt_sigreturn; + restorer = current->mm->context.vdso + (long)&__kernel_rt_sigreturn; if (ka->sa.sa_flags & SA_RESTORER) restorer = ka->sa.sa_restorer; err |= __put_user(restorer, &frame->pretcode); @@ -522,20 +494,23 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, current->comm, current->pid, frame, regs->eip, frame->pretcode); #endif - return; + return 0; give_sigsegv: force_sigsegv(sig, current); + return -EFAULT; } /* * OK, we're invoking a handler */ -static void +static int handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, sigset_t *oldset, struct pt_regs * regs) { + int ret; + /* Are we from a system call? */ if (regs->orig_eax >= 0) { /* If so, check system call restarting.. */ @@ -569,17 +544,20 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, /* Set up the stack frame */ if (ka->sa.sa_flags & SA_SIGINFO) - setup_rt_frame(sig, ka, info, oldset, regs); + ret = setup_rt_frame(sig, ka, info, oldset, regs); else - setup_frame(sig, ka, oldset, regs); + ret = setup_frame(sig, ka, oldset, regs); - if (!(ka->sa.sa_flags & SA_NODEFER)) { + if (ret == 0) { spin_lock_irq(¤t->sighand->siglock); sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); - sigaddset(¤t->blocked,sig); + if (!(ka->sa.sa_flags & SA_NODEFER)) + sigaddset(¤t->blocked,sig); recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); } + + return ret; } /* @@ -587,27 +565,27 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, * want to handle. Thus you cannot kill init even with a SIGKILL even by * mistake. */ -int fastcall do_signal(struct pt_regs *regs, sigset_t *oldset) +static void fastcall do_signal(struct pt_regs *regs) { siginfo_t info; int signr; struct k_sigaction ka; + sigset_t *oldset; /* * We want the common case to go fast, which * is why we may in certain cases get here from * kernel mode. Just return without doing anything - * if so. + * if so. vm86 regs switched out by assembly code + * before reaching here, so testing against kernel + * CS suffices. */ - if ((regs->xcs & 3) != 3) - return 1; + if (!user_mode(regs)) + return; - if (current->flags & PF_FREEZE) { - refrigerator(0); - goto no_signal; - } - - if (!oldset) + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + oldset = ¤t->saved_sigmask; + else oldset = ¤t->blocked; signr = get_signal_to_deliver(&info, &ka, regs, NULL); @@ -617,39 +595,54 @@ int fastcall do_signal(struct pt_regs *regs, sigset_t *oldset) * have been cleared if the watchpoint triggered * inside the kernel. */ - if (unlikely(current->thread.debugreg[7])) { - loaddebug(¤t->thread, 7); - } + if (unlikely(current->thread.debugreg[7])) + set_debugreg(current->thread.debugreg[7], 7); /* Whee! Actually deliver the signal. */ - handle_signal(signr, &info, &ka, oldset, regs); - return 1; + if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { + /* 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); + } + + return; } - no_signal: /* Did we come from a system call? */ if (regs->orig_eax >= 0) { /* Restart the system call - no handlers present */ - if (regs->eax == -ERESTARTNOHAND || - regs->eax == -ERESTARTSYS || - regs->eax == -ERESTARTNOINTR) { + switch (regs->eax) { + case -ERESTARTNOHAND: + case -ERESTARTSYS: + case -ERESTARTNOINTR: regs->eax = regs->orig_eax; regs->eip -= 2; - } - if (regs->eax == -ERESTART_RESTARTBLOCK){ + break; + + case -ERESTART_RESTARTBLOCK: regs->eax = __NR_restart_syscall; regs->eip -= 2; + break; } } - return 0; + + /* if there's no signal to deliver, we just put the saved sigmask + * back */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) { + clear_thread_flag(TIF_RESTORE_SIGMASK); + sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); + } } /* * notification of userspace execution resumption - * - triggered by current->work.notify_resume + * - triggered by the TIF_WORK_MASK flags */ __attribute__((regparm(3))) -void do_notify_resume(struct pt_regs *regs, sigset_t *oldset, +void do_notify_resume(struct pt_regs *regs, void *_unused, __u32 thread_info_flags) { /* Pending single-step? */ @@ -657,9 +650,10 @@ void do_notify_resume(struct pt_regs *regs, sigset_t *oldset, regs->eflags |= TF_MASK; clear_thread_flag(TIF_SINGLESTEP); } + /* deal with pending signal delivery */ - if (thread_info_flags & _TIF_SIGPENDING) - do_signal(regs,oldset); + if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) + do_signal(regs); clear_thread_flag(TIF_IRET); }