introduce generic sys_sigaltstack(), switch x86 and um to it
Conditional on CONFIG_GENERIC_SIGALTSTACK; architectures that do not
select it are completely unaffected
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 9fe5f94..6ca1e08 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -63,6 +63,7 @@
struct old_linux_dirent;
struct perf_event_attr;
struct file_handle;
+struct sigaltstack;
#include <linux/types.h>
#include <linux/aio_abi.h>
@@ -299,6 +300,11 @@
asmlinkage long sys_sigpending(old_sigset_t __user *set);
asmlinkage long sys_sigprocmask(int how, old_sigset_t __user *set,
old_sigset_t __user *oset);
+#ifdef CONFIG_GENERIC_SIGALTSTACK
+asmlinkage long sys_sigaltstack(const struct sigaltstack __user *uss,
+ struct sigaltstack __user *uoss);
+#endif
+
asmlinkage long sys_getitimer(int which, struct itimerval __user *value);
asmlinkage long sys_setitimer(int which,
struct itimerval __user *value,