x86/entry: Refactor COND_SYSCALL macros

Pull the common code out from the COND_SYSCALL macros into a new
__COND_SYSCALL macro.  Also conditionalize the X64 version in preparation
for enabling syscall wrappers on 32-bit native kernels.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200313195144.164260-4-brgerst@gmail.com

diff --git a/arch/x86/include/asm/syscall_wrapper.h b/arch/x86/include/asm/syscall_wrapper.h
index 45ad605..0117b25 100644 (file)
--- a/arch/x86/include/asm/syscall_wrapper.h
+++ b/arch/x86/include/asm/syscall_wrapper.h
@@ -35,6 +35,13 @@ struct pt_regs;
                return __se_##name(__VA_ARGS__);                        \
        }
 
+#define __COND_SYSCALL(abi, name)                                      \
+       asmlinkage __weak long                                          \
+       __##abi##_##name(const struct pt_regs *__unused)                \
+       {                                                               \
+               return sys_ni_syscall();                                \
+       }
+
 #ifdef CONFIG_X86_64
 #define __X64_SYS_STUB0(name)                                          \
        __SYS_STUB0(x64, sys_##name)
@@ -42,9 +49,13 @@ struct pt_regs;
 #define __X64_SYS_STUBx(x, name, ...)                                  \
        __SYS_STUBx(x64, sys##name,                                     \
                    SC_X86_64_REGS_TO_ARGS(x, __VA_ARGS__))
+
+#define __X64_COND_SYSCALL(name)                                       \
+       __COND_SYSCALL(x64, sys_##name)
 #else /* CONFIG_X86_64 */
 #define __X64_SYS_STUB0(name)
 #define __X64_SYS_STUBx(x, name, ...)
+#define __X64_COND_SYSCALL(name)
 #endif /* CONFIG_X86_64 */
 
 #ifdef CONFIG_IA32_EMULATION
@@ -63,6 +74,9 @@ struct pt_regs;
        __SYS_STUBx(ia32, compat_sys##name,                             \
                    SC_IA32_REGS_TO_ARGS(x, __VA_ARGS__))
 
+#define __IA32_COMPAT_COND_SYSCALL(name)                               \
+       __COND_SYSCALL(ia32, compat_sys_##name)
+
 #define __IA32_SYS_STUB0(name)                                         \
        __SYS_STUB0(ia32, sys_##name)
 
@@ -70,15 +84,8 @@ struct pt_regs;
        __SYS_STUBx(ia32, sys##name,                                    \
                    SC_IA32_REGS_TO_ARGS(x, __VA_ARGS__))
 
-#define COND_SYSCALL(name)                                                     \
-       asmlinkage __weak long __x64_sys_##name(const struct pt_regs *__unused) \
-       {                                                                       \
-               return sys_ni_syscall();                                        \
-       }                                                                       \
-       asmlinkage __weak long __ia32_sys_##name(const struct pt_regs *__unused)\
-       {                                                                       \
-               return sys_ni_syscall();                                        \
-       }
+#define __IA32_COND_SYSCALL(name)                                      \
+       __COND_SYSCALL(ia32, sys_##name)
 
 #define SYS_NI(name)                                                   \
        SYSCALL_ALIAS(__x64_sys_##name, sys_ni_posix_timers);           \
@@ -87,8 +94,10 @@ struct pt_regs;
 #else /* CONFIG_IA32_EMULATION */
 #define __IA32_COMPAT_SYS_STUB0(name)
 #define __IA32_COMPAT_SYS_STUBx(x, name, ...)
+#define __IA32_COMPAT_COND_SYSCALL(name)
 #define __IA32_SYS_STUB0(name)
 #define __IA32_SYS_STUBx(x, name, ...)
+#define __IA32_COND_SYSCALL(name)
 #endif /* CONFIG_IA32_EMULATION */
 
 
@@ -105,9 +114,12 @@ struct pt_regs;
        __SYS_STUBx(x32, compat_sys##name,                              \
                    SC_X86_64_REGS_TO_ARGS(x, __VA_ARGS__))
 
+#define __X32_COMPAT_COND_SYSCALL(name)                                        \
+       __COND_SYSCALL(x32, compat_sys_##name)
 #else /* CONFIG_X86_X32 */
 #define __X32_COMPAT_SYS_STUB0(name)
 #define __X32_COMPAT_SYS_STUBx(x, name, ...)
+#define __X32_COMPAT_COND_SYSCALL(name)
 #endif /* CONFIG_X86_X32 */
 
 
@@ -142,8 +154,8 @@ struct pt_regs;
  * kernel/time/posix-stubs.c to cover this case as well.
  */
 #define COND_SYSCALL_COMPAT(name)                                      \
-       cond_syscall(__ia32_compat_sys_##name);                         \
-       cond_syscall(__x32_compat_sys_##name)
+       __IA32_COMPAT_COND_SYSCALL(name)                                \
+       __X32_COMPAT_COND_SYSCALL(name)
 
 #define COMPAT_SYS_NI(name)                                            \
        SYSCALL_ALIAS(__ia32_compat_sys_##name, sys_ni_posix_timers);   \
@@ -215,13 +227,9 @@ struct pt_regs;
        static asmlinkage long                                          \
        __do_sys_##sname(const struct pt_regs *__unused)
 
-#ifndef COND_SYSCALL
-#define COND_SYSCALL(name)                                                     \
-       asmlinkage __weak long __x64_sys_##name(const struct pt_regs *__unused) \
-       {                                                                       \
-               return sys_ni_syscall();                                        \
-       }
-#endif
+#define COND_SYSCALL(name)                                             \
+       __X64_COND_SYSCALL(name)                                        \
+       __IA32_COND_SYSCALL(name)
 
 #ifndef SYS_NI
 #define SYS_NI(name) SYSCALL_ALIAS(__x64_sys_##name, sys_ni_posix_timers);