x86/entry: Remove ABI prefixes from functions in syscall tables

Move the ABI prefixes to the __SYSCALL_[abi]() macros.  This allows removal
of the need to strip the prefix for UML.
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200313195144.164260-13-brgerst@gmail.com

arch/x86/entry/syscall_32.c

@@ -9,7 +9,7 @@
 
 #ifdef CONFIG_IA32_EMULATION
 /* On X86_64, we use struct pt_regs * to pass parameters to syscalls */
-#define __SYSCALL_I386(nr, sym) extern asmlinkage long sym(const struct pt_regs *);
+#define __SYSCALL_I386(nr, sym) extern asmlinkage long __ia32_##sym(const struct pt_regs *);
 #define __sys_ni_syscall __ia32_sys_ni_syscall
 #else /* CONFIG_IA32_EMULATION */
 #define __SYSCALL_I386(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
@@ -20,7 +20,11 @@ extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned lon
 #include <asm/syscalls_32.h>
 #undef __SYSCALL_I386
 
+#ifdef CONFIG_IA32_EMULATION
+#define __SYSCALL_I386(nr, sym) [nr] = __ia32_##sym,
+#else /* CONFIG_IA32_EMULATION */
 #define __SYSCALL_I386(nr, sym) [nr] = sym,
+#endif /* CONFIG_IA32_EMULATION */
 
 __visible const sys_call_ptr_t ia32_sys_call_table[__NR_ia32_syscall_max+1] = {
 	/*

arch/x86/entry/syscall_64.c

@@ -11,11 +11,11 @@
 #define __SYSCALL_X32(nr, sym)
 #define __SYSCALL_COMMON(nr, sym) __SYSCALL_64(nr, sym)
 
-#define __SYSCALL_64(nr, sym) extern asmlinkage long sym(const struct pt_regs *);
+#define __SYSCALL_64(nr, sym) extern asmlinkage long __x64_##sym(const struct pt_regs *);
 #include <asm/syscalls_64.h>
 #undef __SYSCALL_64
 
-#define __SYSCALL_64(nr, sym) [nr] = sym,
+#define __SYSCALL_64(nr, sym) [nr] = __x64_##sym,
 
 asmlinkage const sys_call_ptr_t sys_call_table[__NR_syscall_max+1] = {
 	/*

arch/x86/entry/syscall_x32.c

@@ -10,14 +10,14 @@
 
 #define __SYSCALL_64(nr, sym)
 
-#define __SYSCALL_X32(nr, sym) extern asmlinkage long sym(const struct pt_regs *);
-#define __SYSCALL_COMMON(nr, sym) extern asmlinkage long sym(const struct pt_regs *);
+#define __SYSCALL_X32(nr, sym) extern asmlinkage long __x32_##sym(const struct pt_regs *);
+#define __SYSCALL_COMMON(nr, sym) extern asmlinkage long __x64_##sym(const struct pt_regs *);
 #include <asm/syscalls_64.h>
 #undef __SYSCALL_X32
 #undef __SYSCALL_COMMON
 
-#define __SYSCALL_X32(nr, sym) [nr] = sym,
-#define __SYSCALL_COMMON(nr, sym) [nr] = sym,
+#define __SYSCALL_X32(nr, sym) [nr] = __x32_##sym,
+#define __SYSCALL_COMMON(nr, sym) [nr] = __x64_##sym,
 
 asmlinkage const sys_call_ptr_t x32_sys_call_table[__NR_x32_syscall_max+1] = {
 	/*

arch/x86/entry/syscalls/syscalltbl.sh

@@ -17,27 +17,15 @@ emit() {
     local nr="$2"
     local entry="$3"
     local compat="$4"
-    local umlentry=""
 
     if [ "$abi" != "I386" -a -n "$compat" ]; then
 	echo "a compat entry ($abi: $compat) for a 64-bit syscall makes no sense" >&2
 	exit 1
     fi
 
-    # For CONFIG_UML, we need to strip the __x64_sys prefix
-    if [ "${entry}" != "${entry#__x64_sys}" ]; then
-	    umlentry="sys${entry#__x64_sys}"
-    fi
-
     if [ -z "$compat" ]; then
-	if [ -n "$entry" -a -z "$umlentry" ]; then
-	    syscall_macro "$abi" "$nr" "$entry"
-	elif [ -n "$umlentry" ]; then # implies -n "$entry"
-	    echo "#ifdef CONFIG_X86"
+	if [ -n "$entry" ]; then
 	    syscall_macro "$abi" "$nr" "$entry"
-	    echo "#else /* CONFIG_UML */"
-	    syscall_macro "$abi" "$nr" "$umlentry"
-	    echo "#endif"
 	fi
     else
 	echo "#ifdef CONFIG_X86_32"