switch epoll_pwait to COMPAT_SYSCALL_DEFINE

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

arch/s390/kernel/compat_wrapper.S

@@ -1270,16 +1270,6 @@ ENTRY(sys_getcpu_wrapper)
 	llgtr	%r4,%r4			# struct getcpu_cache *
 	jg	sys_getcpu
 
-ENTRY(compat_sys_epoll_pwait_wrapper)
-	lgfr	%r2,%r2			# int
-	llgtr	%r3,%r3			# struct compat_epoll_event *
-	lgfr	%r4,%r4			# int
-	lgfr	%r5,%r5			# int
-	llgtr	%r6,%r6			# compat_sigset_t *
-	llgf	%r0,164(%r15)		# compat_size_t
-	stg	%r0,160(%r15)
-	jg	compat_sys_epoll_pwait
-
 ENTRY(compat_sys_utimes_wrapper)
 	llgtr	%r2,%r2			# char *
 	llgtr	%r3,%r3			# struct compat_timeval *

arch/s390/kernel/syscalls.S

@@ -320,7 +320,7 @@ SYSCALL(sys_tee,sys_tee,sys_tee_wrapper)
 SYSCALL(sys_vmsplice,sys_vmsplice,compat_sys_vmsplice_wrapper)
 NI_SYSCALL							/* 310 sys_move_pages */
 SYSCALL(sys_getcpu,sys_getcpu,sys_getcpu_wrapper)
-SYSCALL(sys_epoll_pwait,sys_epoll_pwait,compat_sys_epoll_pwait_wrapper)
+SYSCALL(sys_epoll_pwait,sys_epoll_pwait,compat_sys_epoll_pwait)
 SYSCALL(sys_utimes,sys_utimes,compat_sys_utimes_wrapper)
 SYSCALL(sys_s390_fallocate,sys_fallocate,sys_fallocate_wrapper)
 SYSCALL(sys_utimensat,sys_utimensat,compat_sys_utimensat_wrapper)	/* 315 */

fs/compat.c

@@ -44,7 +44,6 @@
 #include <linux/signal.h>
 #include <linux/poll.h>
 #include <linux/mm.h>
-#include <linux/eventpoll.h>
 #include <linux/fs_struct.h>
 #include <linux/slab.h>
 #include <linux/pagemap.h>
@@ -1659,54 +1658,6 @@ asmlinkage long compat_sys_ppoll(struct pollfd __user *ufds,
 	return ret;
 }
 
-#ifdef CONFIG_EPOLL
-
-asmlinkage long compat_sys_epoll_pwait(int epfd,
-			struct compat_epoll_event __user *events,
-			int maxevents, int timeout,
-			const compat_sigset_t __user *sigmask,
-			compat_size_t sigsetsize)
-{
-	long err;
-	compat_sigset_t csigmask;
-	sigset_t ksigmask, sigsaved;
-
-	/*
-	 * If the caller wants a certain signal mask to be set during the wait,
-	 * we apply it here.
-	 */
-	if (sigmask) {
-		if (sigsetsize != sizeof(compat_sigset_t))
-			return -EINVAL;
-		if (copy_from_user(&csigmask, sigmask, sizeof(csigmask)))
-			return -EFAULT;
-		sigset_from_compat(&ksigmask, &csigmask);
-		sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
-		sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
-	}
-
-	err = sys_epoll_wait(epfd, events, maxevents, timeout);
-
-	/*
-	 * If we changed the signal mask, we need to restore the original one.
-	 * In case we've got a signal while waiting, we do not restore the
-	 * signal mask yet, and we allow do_signal() to deliver the signal on
-	 * the way back to userspace, before the signal mask is restored.
-	 */
-	if (sigmask) {
-		if (err == -EINTR) {
-			memcpy(&current->saved_sigmask, &sigsaved,
-			       sizeof(sigsaved));
-			set_restore_sigmask();
-		} else
-			sigprocmask(SIG_SETMASK, &sigsaved, NULL);
-	}
-
-	return err;
-}
-
-#endif /* CONFIG_EPOLL */
-
 #ifdef CONFIG_FHANDLE
 /*
  * Exactly like fs/open.c:sys_open_by_handle_at(), except that it

fs/eventpoll.c

@@ -40,6 +40,7 @@
 #include <linux/atomic.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
+#include <linux/compat.h>
 
 /*
  * LOCKING:
@@ -1940,6 +1941,52 @@ SYSCALL_DEFINE6(epoll_pwait, int, epfd, struct epoll_event __user *, events,
 	return error;
 }
 
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE6(epoll_pwait, int, epfd,
+			struct epoll_event __user *, events,
+			int, maxevents, int, timeout,
+			const compat_sigset_t __user *, sigmask,
+			compat_size_t, sigsetsize)
+{
+	long err;
+	compat_sigset_t csigmask;
+	sigset_t ksigmask, sigsaved;
+
+	/*
+	 * If the caller wants a certain signal mask to be set during the wait,
+	 * we apply it here.
+	 */
+	if (sigmask) {
+		if (sigsetsize != sizeof(compat_sigset_t))
+			return -EINVAL;
+		if (copy_from_user(&csigmask, sigmask, sizeof(csigmask)))
+			return -EFAULT;
+		sigset_from_compat(&ksigmask, &csigmask);
+		sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
+		sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
+	}
+
+	err = sys_epoll_wait(epfd, events, maxevents, timeout);
+
+	/*
+	 * If we changed the signal mask, we need to restore the original one.
+	 * In case we've got a signal while waiting, we do not restore the
+	 * signal mask yet, and we allow do_signal() to deliver the signal on
+	 * the way back to userspace, before the signal mask is restored.
+	 */
+	if (sigmask) {
+		if (err == -EINTR) {
+			memcpy(&current->saved_sigmask, &sigsaved,
+			       sizeof(sigsaved));
+			set_restore_sigmask();
+		} else
+			sigprocmask(SIG_SETMASK, &sigsaved, NULL);
+	}
+
+	return err;
+}
+#endif
+
 static int __init eventpoll_init(void)
 {
 	struct sysinfo si;

include/linux/compat.h

@@ -432,10 +432,9 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
 /*
  * epoll (fs/eventpoll.c) compat bits follow ...
  */
-struct epoll_event;
-#define compat_epoll_event	epoll_event
+struct epoll_event;	/* fortunately, this one is fixed-layout */
 asmlinkage long compat_sys_epoll_pwait(int epfd,
-			struct compat_epoll_event __user *events,
+			struct epoll_event __user *events,
 			int maxevents, int timeout,
 			const compat_sigset_t __user *sigmask,
 			compat_size_t sigsetsize);