um: simplify syscall header files

Since Thomas's recent commit 2af1053 ("um/x86: Add
system call table to header file") , we now have two
extern declarations of the syscall table, one internal
and one external, and they don't even match on 32-bit.
Clean this up and remove all the extra code.

Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20250704141243.a68366f6acc3.If8587a4aafdb90644fc6d0b2f5e31a2d1887915f@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Author: jmberg-intel

arch/um/kernel/skas/syscall.c

@@ -9,8 +9,8 @@
 #include <kern_util.h>
 #include <sysdep/ptrace.h>
 #include <sysdep/ptrace_user.h>
-#include <sysdep/syscalls.h>
 #include <linux/time-internal.h>
+#include <asm/syscall.h>
 #include <asm/unistd.h>
 #include <asm/delay.h>
 
@@ -43,7 +43,14 @@ void handle_syscall(struct uml_pt_regs *r)
 		tt_extra_sched_jiffies += 1;
 
 	if (syscall >= 0 && syscall < __NR_syscalls) {
-		unsigned long ret = EXECUTE_SYSCALL(syscall, regs);
+		unsigned long ret;
+
+		ret = (*sys_call_table[syscall])(UPT_SYSCALL_ARG1(&regs->regs),
+						 UPT_SYSCALL_ARG2(&regs->regs),
+						 UPT_SYSCALL_ARG3(&regs->regs),
+						 UPT_SYSCALL_ARG4(&regs->regs),
+						 UPT_SYSCALL_ARG5(&regs->regs),
+						 UPT_SYSCALL_ARG6(&regs->regs));
 
 		PT_REGS_SET_SYSCALL_RETURN(regs, ret);
 

arch/x86/um/shared/sysdep/ptrace.h

@@ -44,18 +44,6 @@
 #include "ptrace_64.h"
 #endif
 
-struct syscall_args {
-	unsigned long args[6];
-};
-
-#define SYSCALL_ARGS(r) ((struct syscall_args) \
-			 { .args = { UPT_SYSCALL_ARG1(r),	 \
-				     UPT_SYSCALL_ARG2(r),	 \
-				     UPT_SYSCALL_ARG3(r),	 \
-				     UPT_SYSCALL_ARG4(r),	 \
-				     UPT_SYSCALL_ARG5(r),	 \
-				     UPT_SYSCALL_ARG6(r) } } )
-
 extern unsigned long host_fp_size;
 
 struct uml_pt_regs {