[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>

2 files changed, 54 insertions, 0 deletions

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 =