ipc: add msgctl syscall/compat_syscall wrappers

Provide ksys_msgctl() and compat_ksys_msgctl() wrappers to avoid in-kernel
calls to these syscalls. The ksys_ prefix denotes that these functions are
meant as a drop-in replacement for the syscalls. In particular, they use
the same calling convention as sys_msgctl() and compat_sys_msgctl().

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

1 files changed, 3 insertions, 2 deletions

diff --git a/ipc/syscall.c b/ipc/syscall.c
index 34bbabc9e672..aa29b0802e26 100644
--- a/ipc/syscall.c
+++ b/ipc/syscall.c
@@ -70,7 +70,8 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
         case MSGGET:
                 return ksys_msgget((key_t) first, second);
         case MSGCTL:
-                return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);
+                return ksys_msgctl(first, second,
+                                   (struct msqid_ds __user *)ptr);
 
         case SHMAT:
                 switch (version) {
@@ -163,7 +164,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
         case MSGGET:
                 return ksys_msgget(first, second);
         case MSGCTL:
-                return compat_sys_msgctl(first, second, compat_ptr(ptr));
+                return compat_ksys_msgctl(first, second, compat_ptr(ptr));
 
         case SHMAT: {
                 int err;