xref: /linux/arch/um/kernel/skas/syscall.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /*
2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5 
6 #include "linux/sys.h"
7 #include "linux/ptrace.h"
8 #include "asm/errno.h"
9 #include "asm/unistd.h"
10 #include "asm/ptrace.h"
11 #include "asm/current.h"
12 #include "sysdep/syscalls.h"
13 #include "kern_util.h"
14 #include "syscall.h"
15 
16 void handle_syscall(union uml_pt_regs *r)
17 {
18 	struct pt_regs *regs = container_of(r, struct pt_regs, regs);
19 	long result;
20 	int syscall;
21 
22 	syscall_trace(r, 0);
23 
24 	current->thread.nsyscalls++;
25 	nsyscalls++;
26 
27 	/* This should go in the declaration of syscall, but when I do that,
28 	 * strace -f -c bash -c 'ls ; ls' breaks, sometimes not tracing
29 	 * children at all, sometimes hanging when bash doesn't see the first
30 	 * ls exit.
31 	 * The assembly looks functionally the same to me.  This is
32 	 *     gcc version 4.0.1 20050727 (Red Hat 4.0.1-5)
33 	 * in case it's a compiler bug.
34 	 */
35 	syscall = UPT_SYSCALL_NR(r);
36 	if((syscall >= NR_syscalls) || (syscall < 0))
37 		result = -ENOSYS;
38 	else result = EXECUTE_SYSCALL(syscall, regs);
39 
40 	REGS_SET_SYSCALL_RETURN(r->skas.regs, result);
41 
42 	syscall_trace(r, 1);
43 }
44