old sigsuspend variants in kernel/signal.c

conditional on OLD_SIGSUSPEND/OLD_SIGSUSPEND3, depending on which
variety of that fossil is needed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 35 insertions, 0 deletions

diff --git a/arch/Kconfig b/arch/Kconfig
index c612b5ccfd84..6b1df95ffefc 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -387,4 +387,14 @@ config ODD_RT_SIGACTION
         help
           Architecture has unusual rt_sigaction(2) arguments
 
+config OLD_SIGSUSPEND
+        bool
+        help
+          Architecture has old sigsuspend(2) syscall, of one-argument variety
+
+config OLD_SIGSUSPEND3
+        bool
+        help
+          Even weirder antique ABI - three-argument sigsuspend(2)
+
 source "kernel/gcov/Kconfig"
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 75defcd1c276..d2dd2f63d220 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -377,6 +377,14 @@ asmlinkage long sys_init_module(void __user *umod, unsigned long len,
 asmlinkage long sys_delete_module(const char __user *name_user,
                                 unsigned int flags);
 
+#ifdef CONFIG_OLD_SIGSUSPEND
+asmlinkage long sys_sigsuspend(old_sigset_t mask);
+#endif
+
+#ifdef CONFIG_OLD_SIGSUSPEND3
+asmlinkage long sys_sigsuspend(int unused1, int unused2, old_sigset_t mask);
+#endif
+
 #ifndef CONFIG_ODD_RT_SIGACTION
 asmlinkage long sys_rt_sigaction(int,
                                  const struct sigaction __user *,
diff --git a/kernel/signal.c b/kernel/signal.c
index 6cd3023cc66b..93fd4b83d866 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3454,6 +3454,23 @@ COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_
 #endif
 #endif
 
+#ifdef CONFIG_OLD_SIGSUSPEND
+SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask)
+{
+        sigset_t blocked;
+        siginitset(&blocked, mask);
+        return sigsuspend(&blocked);
+}
+#endif
+#ifdef CONFIG_OLD_SIGSUSPEND3
+SYSCALL_DEFINE3(sigsuspend, int, unused1, int, unused2, old_sigset_t, mask)
+{
+        sigset_t blocked;
+        siginitset(&blocked, mask);
+        return sigsuspend(&blocked);
+}
+#endif
+
 __attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma)
 {
         return NULL;