[PATCH] Generic sys_rt_sigsuspend()

The TIF_RESTORE_SIGMASK flag allows us to have a generic implementation of
sys_rt_sigsuspend() instead of duplicating it for each architecture.  This
provides such an implementation and makes arch/powerpc use it.

It also tidies up the ppc32 sys_sigsuspend() to use TIF_RESTORE_SIGMASK.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

6 files changed, 62 insertions, 87 deletions

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 177bba78fb0b..7f0d5ce2567d 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -252,8 +252,7 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs);
 /*
  * Atomically swap in the new signal mask, and wait for a signal.
  */
-long sys_sigsuspend(old_sigset_t mask, int p2, int p3, int p4, int p6, int p7,
-               struct pt_regs *regs)
+long sys_sigsuspend(old_sigset_t mask)
 {
         sigset_t saveset;
 
@@ -264,55 +263,10 @@ long sys_sigsuspend(old_sigset_t mask, int p2, int p3, int p4, int p6, int p7,
         recalc_sigpending();
         spin_unlock_irq(&current->sighand->siglock);
 
-        regs->result = -EINTR;
-        regs->gpr[3] = EINTR;
-        regs->ccr |= 0x10000000;
-        while (1) {
-                current->state = TASK_INTERRUPTIBLE;
-                schedule();
-                if (do_signal(&saveset, regs)) {
-                        set_thread_flag(TIF_RESTOREALL);
-                        return 0;
-                }
-        }
-}
-
-long sys_rt_sigsuspend(
-#ifdef CONFIG_PPC64
-                compat_sigset_t __user *unewset,
-#else
-                sigset_t __user *unewset,
-#endif
-                size_t sigsetsize, int p3, int p4,
-                int p6, int p7, struct pt_regs *regs)
-{
-        sigset_t saveset, newset;
-
-        /* XXX: Don't preclude handling different sized sigset_t's.  */
-        if (sigsetsize != sizeof(sigset_t))
-                return -EINVAL;
-
-        if (get_sigset_t(&newset, unewset))
-                return -EFAULT;
-        sigdelsetmask(&newset, ~_BLOCKABLE);
-
-        spin_lock_irq(&current->sighand->siglock);
-        saveset = current->blocked;
-        current->blocked = newset;
-        recalc_sigpending();
-        spin_unlock_irq(&current->sighand->siglock);
-
-        regs->result = -EINTR;
-        regs->gpr[3] = EINTR;
-        regs->ccr |= 0x10000000;
-        while (1) {
-                current->state = TASK_INTERRUPTIBLE;
-                schedule();
-                if (do_signal(&saveset, regs)) {
-                        set_thread_flag(TIF_RESTOREALL);
-                        return 0;
-                }
-        }
+        current->state = TASK_INTERRUPTIBLE;
+        schedule();
+        set_thread_flag(TIF_RESTORE_SIGMASK);
+        return -ERESTARTNOHAND;
 }
 
 #ifdef CONFIG_PPC32
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 7b9d999e2115..a4a6812e815e 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -67,42 +67,6 @@ struct rt_sigframe {
         char abigap[288];
 } __attribute__ ((aligned (16)));
 
-
-/*
- * Atomically swap in the new signal mask, and wait for a signal.
- */
-long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, int p3, int p4,
-                       int p6, int p7, struct pt_regs *regs)
-{
-        sigset_t saveset, newset;
-
-        /* XXX: Don't preclude handling different sized sigset_t's.  */
-        if (sigsetsize != sizeof(sigset_t))
-                return -EINVAL;
-
-        if (copy_from_user(&newset, unewset, sizeof(newset)))
-                return -EFAULT;
-        sigdelsetmask(&newset, ~_BLOCKABLE);
-
-        spin_lock_irq(&current->sighand->siglock);
-        saveset = current->blocked;
-        current->blocked = newset;
-        recalc_sigpending();
-        spin_unlock_irq(&current->sighand->siglock);
-
-        regs->result = -EINTR;
-        regs->gpr[3] = EINTR;
-        regs->ccr |= 0x10000000;
-        while (1) {
-                current->state = TASK_INTERRUPTIBLE;
-                schedule();
-                if (do_signal(&saveset, regs)) {
-                        set_thread_flag(TIF_RESTOREALL);
-                        return 0;
-                }
-        }
-}
-
 long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, unsigned long r5,
                      unsigned long r6, unsigned long r7, unsigned long r8,
                      struct pt_regs *regs)
diff --git a/include/asm-powerpc/unistd.h b/include/asm-powerpc/unistd.h
index 19eaac3fbbf9..76daec496062 100644
--- a/include/asm-powerpc/unistd.h
+++ b/include/asm-powerpc/unistd.h
@@ -444,11 +444,13 @@ type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4, type5 arg5, type6 arg6
 #define __ARCH_WANT_SYS_SIGPENDING
 #define __ARCH_WANT_SYS_SIGPROCMASK
 #define __ARCH_WANT_SYS_RT_SIGACTION
+#define __ARCH_WANT_SYS_RT_SIGSUSPEND
 #ifdef CONFIG_PPC32
 #define __ARCH_WANT_OLD_STAT
 #endif
 #ifdef CONFIG_PPC64
 #define __ARCH_WANT_COMPAT_SYS_TIME
+#define __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
 #endif
 
 /*
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 2df1a1a2fee5..0cfcd1c7865e 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -809,6 +809,7 @@ struct task_struct {
         struct sighand_struct *sighand;
 
         sigset_t blocked, real_blocked;
+        sigset_t saved_sigmask;         /* To be restored with TIF_RESTORE_SIGMASK */
         struct sigpending pending;
 
         unsigned long sas_ss_sp;
diff --git a/kernel/compat.c b/kernel/compat.c
index 256e5d9f0647..1867290c37e3 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -871,3 +871,31 @@ asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
 }
 
 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
+
+#ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
+asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
+{
+        sigset_t newset;
+        compat_sigset_t newset32;
+
+        /* XXX: Don't preclude handling different sized sigset_t's.  */
+        if (sigsetsize != sizeof(sigset_t))
+                return -EINVAL;
+
+        if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
+                return -EFAULT;
+        sigset_from_compat(&newset, &newset32);
+        sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+        spin_lock_irq(&current->sighand->siglock);
+        current->saved_sigmask = current->blocked;
+        current->blocked = newset;
+        recalc_sigpending();
+        spin_unlock_irq(&current->sighand->siglock);
+
+        current->state = TASK_INTERRUPTIBLE;
+        schedule();
+        set_thread_flag(TIF_RESTORE_SIGMASK);
+        return -ERESTARTNOHAND;
+}
+#endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
diff --git a/kernel/signal.c b/kernel/signal.c
index 5dafbd36d62e..d3efafd8109a 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2721,6 +2721,32 @@ sys_pause(void)
 
 #endif
 
+#ifdef __ARCH_WANT_SYS_RT_SIGSUSPEND
+asmlinkage long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize)
+{
+        sigset_t newset;
+
+        /* XXX: Don't preclude handling different sized sigset_t's.  */
+        if (sigsetsize != sizeof(sigset_t))
+                return -EINVAL;
+
+        if (copy_from_user(&newset, unewset, sizeof(newset)))
+                return -EFAULT;
+        sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+        spin_lock_irq(&current->sighand->siglock);
+        current->saved_sigmask = current->blocked;
+        current->blocked = newset;
+        recalc_sigpending();
+        spin_unlock_irq(&current->sighand->siglock);
+
+        current->state = TASK_INTERRUPTIBLE;
+        schedule();
+        set_thread_flag(TIF_RESTORE_SIGMASK);
+        return -ERESTARTNOHAND;
+}
+#endif /* __ARCH_WANT_SYS_RT_SIGSUSPEND */
+
 void __init signals_init(void)
 {
         sigqueue_cachep =