[PATCH 1/4] Move userspace syscall dispatch outside of common entry

[houdek.ryan at fex-emu.org]

From: Ryan Houdek <Houdek.Ryan at fex-emu.org>

This will allow other architectures to support userspace syscall
dispatch without supporting the syscall common entry.

Signed-off-by: Ryan Houdek <Houdek.Ryan at fex-emu.org>
---
 arch/Kconfig                          | 4 ++++
 include/linux/syscall_user_dispatch.h | 4 +++-
 kernel/entry/Makefile                 | 3 ++-
 kernel/entry/common.c                 | 3 +--
 kernel/entry/common.h                 | 7 -------
 kernel/entry/syscall_user_dispatch.c  | 2 --
 6 files changed, 10 insertions(+), 13 deletions(-)
 delete mode 100644 kernel/entry/common.h

diff --git a/arch/Kconfig b/arch/Kconfig
index c45b770d3579..def67ebbae83 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -30,7 +30,11 @@ config SET_FS
 config HOTPLUG_SMT
 	bool
 
+config SYSCALL_USER_DISPATCH
+       bool
+
 config GENERIC_ENTRY
+       select SYSCALL_USER_DISPATCH
        bool
 
 config KPROBES
diff --git a/include/linux/syscall_user_dispatch.h b/include/linux/syscall_user_dispatch.h
index a0ae443fb7df..9d1e244d7021 100644
--- a/include/linux/syscall_user_dispatch.h
+++ b/include/linux/syscall_user_dispatch.h
@@ -7,7 +7,7 @@
 
 #include <linux/thread_info.h>
 
-#ifdef CONFIG_GENERIC_ENTRY
+#ifdef CONFIG_SYSCALL_USER_DISPATCH
 
 struct syscall_user_dispatch {
 	char __user	*selector;
@@ -16,6 +16,8 @@ struct syscall_user_dispatch {
 	bool		on_dispatch;
 };
 
+bool syscall_user_dispatch(struct pt_regs *regs);
+
 int set_syscall_user_dispatch(unsigned long mode, unsigned long offset,
 			      unsigned long len, char __user *selector);
 
diff --git a/kernel/entry/Makefile b/kernel/entry/Makefile
index 095c775e001e..35684390d56e 100644
--- a/kernel/entry/Makefile
+++ b/kernel/entry/Makefile
@@ -9,5 +9,6 @@ KCOV_INSTRUMENT := n
 CFLAGS_REMOVE_common.o	 = -fstack-protector -fstack-protector-strong
 CFLAGS_common.o		+= -fno-stack-protector
 
-obj-$(CONFIG_GENERIC_ENTRY) 		+= common.o syscall_user_dispatch.o
+obj-$(CONFIG_GENERIC_ENTRY) 		+= common.o
+obj-$(CONFIG_SYSCALL_USER_DISPATCH)	+= syscall_user_dispatch.o
 obj-$(CONFIG_KVM_XFER_TO_GUEST_WORK)	+= kvm.o
diff --git a/kernel/entry/common.c b/kernel/entry/common.c
index a0b3b04fb596..84ea1e66e0b2 100644
--- a/kernel/entry/common.c
+++ b/kernel/entry/common.c
@@ -5,8 +5,7 @@
 #include <linux/highmem.h>
 #include <linux/livepatch.h>
 #include <linux/audit.h>
-
-#include "common.h"
+#include <linux/syscall_user_dispatch.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/syscalls.h>
diff --git a/kernel/entry/common.h b/kernel/entry/common.h
deleted file mode 100644
index f6e6d02f07fe..000000000000
--- a/kernel/entry/common.h
+++ /dev/null
@@ -1,7 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _COMMON_H
-#define _COMMON_H
-
-bool syscall_user_dispatch(struct pt_regs *regs);
-
-#endif
diff --git a/kernel/entry/syscall_user_dispatch.c b/kernel/entry/syscall_user_dispatch.c
index c240302f56e2..352da8427b01 100644
--- a/kernel/entry/syscall_user_dispatch.c
+++ b/kernel/entry/syscall_user_dispatch.c
@@ -14,8 +14,6 @@
 
 #include <asm/syscall.h>
 
-#include "common.h"
-
 static void trigger_sigsys(struct pt_regs *regs)
 {
 	struct kernel_siginfo info;
-- 
2.30.2