diff options
author | David Howells <dhowells@redhat.com> | 2006-01-19 01:44:00 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-01-19 03:20:29 (GMT) |
commit | 283828f3c19ceb3a64a8544d42cc189003e8b0fe (patch) | |
tree | a3ba8f54e809bc1036bce6a404d88c93d578b0c2 | |
parent | a411aee96ea7fe6fe065df65bf29ea755bcdb554 (diff) | |
download | linux-fsl-qoriq-283828f3c19ceb3a64a8544d42cc189003e8b0fe.tar.xz |
[PATCH] Handle TIF_RESTORE_SIGMASK for i386
Handle TIF_RESTORE_SIGMASK as added by David Woodhouse's patch entitled:
[PATCH] 2/3 Add TIF_RESTORE_SIGMASK support for arch/powerpc
[PATCH] 3/3 Generic sys_rt_sigsuspend
It does the following:
(1) Declares TIF_RESTORE_SIGMASK for i386.
(2) Invokes it over to do_signal() when TIF_RESTORE_SIGMASK is set.
(3) Makes do_signal() support TIF_RESTORE_SIGMASK, using the signal mask saved
in current->saved_sigmask.
(4) Discards sys_rt_sigsuspend() from the arch, using the generic one instead.
(5) Makes sys_sigsuspend() save the signal mask and set TIF_RESTORE_SIGMASK
rather than attempting to fudge the return registers.
(6) Makes sys_sigsuspend() return -ERESTARTNOHAND rather than looping
intrinsically.
(7) Makes setup_frame(), setup_rt_frame() and handle_signal() return 0 or
-EFAULT rather than true/false to be consistent with the rest of the
kernel.
Due to the fact do_signal() is then only called from one place:
(8) Makes do_signal() no longer have a return value is it was just being
ignored; force_sig() takes care of this.
(9) Discards the old sigmask argument to do_signal() as it's no longer
necessary.
(10) Makes do_signal() static.
(11) Marks the second argument to do_notify_resume() as unused. The unused
argument should remain in the middle as the arguments are passed in as
registers, and the ordering is specific in entry.S
Given the way do_signal() is now no longer called from sys_{,rt_}sigsuspend(),
they no longer need access to the exception frame, and so can just take
arguments normally.
This patch depends on sys_rt_sigsuspend patch.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r-- | arch/i386/kernel/signal.c | 109 | ||||
-rw-r--r-- | include/asm-i386/signal.h | 1 | ||||
-rw-r--r-- | include/asm-i386/thread_info.h | 2 | ||||
-rw-r--r-- | include/asm-i386/unistd.h | 1 |
4 files changed, 51 insertions, 62 deletions
diff --git a/arch/i386/kernel/signal.c b/arch/i386/kernel/signal.c index adcd069..963616d 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 @@ -433,11 +399,11 @@ static int setup_frame(int sig, struct k_sigaction *ka, current->comm, current->pid, frame, regs->eip, frame->pretcode); #endif - return 1; + return 0; give_sigsegv: force_sigsegv(sig, current); - return 0; + return -EFAULT; } static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, @@ -527,11 +493,11 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, current->comm, current->pid, frame, regs->eip, frame->pretcode); #endif - return 1; + return 0; give_sigsegv: force_sigsegv(sig, current); - return 0; + return -EFAULT; } /* @@ -581,7 +547,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, else ret = setup_frame(sig, ka, oldset, regs); - if (ret) { + if (ret == 0) { spin_lock_irq(¤t->sighand->siglock); sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); if (!(ka->sa.sa_flags & SA_NODEFER)) @@ -598,11 +564,12 @@ 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 @@ -613,12 +580,14 @@ int fastcall do_signal(struct pt_regs *regs, sigset_t *oldset) * CS suffices. */ if (!user_mode(regs)) - return 1; + return; if (try_to_freeze()) 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); @@ -628,38 +597,55 @@ 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])) { + if (unlikely(current->thread.debugreg[7])) set_debugreg(current->thread.debugreg[7], 7); - } /* Whee! Actually deliver the signal. */ - return handle_signal(signr, &info, &ka, oldset, regs); + 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: +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? */ @@ -667,9 +653,10 @@ 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); } diff --git a/include/asm-i386/signal.h b/include/asm-i386/signal.h index 76524b4..026fd23 100644 --- a/include/asm-i386/signal.h +++ b/include/asm-i386/signal.h @@ -218,7 +218,6 @@ static __inline__ int sigfindinword(unsigned long word) } struct pt_regs; -extern int FASTCALL(do_signal(struct pt_regs *regs, sigset_t *oldset)); #define ptrace_signal_deliver(regs, cookie) \ do { \ diff --git a/include/asm-i386/thread_info.h b/include/asm-i386/thread_info.h index 2493e77..e20e995 100644 --- a/include/asm-i386/thread_info.h +++ b/include/asm-i386/thread_info.h @@ -140,6 +140,7 @@ register unsigned long current_stack_pointer asm("esp") __attribute_used__; #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ #define TIF_SECCOMP 8 /* secure computing */ +#define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal() */ #define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */ #define TIF_MEMDIE 17 @@ -152,6 +153,7 @@ register unsigned long current_stack_pointer asm("esp") __attribute_used__; #define _TIF_SYSCALL_EMU (1<<TIF_SYSCALL_EMU) #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1<<TIF_SECCOMP) +#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK) #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG) /* work to do on interrupt/exception return */ diff --git a/include/asm-i386/unistd.h b/include/asm-i386/unistd.h index e3028aa..3400441 100644 --- a/include/asm-i386/unistd.h +++ b/include/asm-i386/unistd.h @@ -430,6 +430,7 @@ __syscall_return(type,__res); \ #define __ARCH_WANT_SYS_SIGPENDING #define __ARCH_WANT_SYS_SIGPROCMASK #define __ARCH_WANT_SYS_RT_SIGACTION +#define __ARCH_WANT_SYS_RT_SIGSUSPEND #endif #ifdef __KERNEL_SYSCALLS__ |