xref: /openbmc/linux/arch/mips/kernel/scall64-n64.S (revision 2c6467d2)
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1995, 96, 97, 98, 99, 2000, 01, 02 by Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Copyright (C) 2001 MIPS Technologies, Inc.
9 */
10#include <linux/errno.h>
11#include <asm/asm.h>
12#include <asm/asmmacro.h>
13#include <asm/irqflags.h>
14#include <asm/mipsregs.h>
15#include <asm/regdef.h>
16#include <asm/stackframe.h>
17#include <asm/asm-offsets.h>
18#include <asm/sysmips.h>
19#include <asm/thread_info.h>
20#include <asm/unistd.h>
21#include <asm/war.h>
22
23#ifndef CONFIG_BINFMT_ELF32
24/* Neither O32 nor N32, so define handle_sys here */
25#define handle_sys64 handle_sys
26#endif
27
28	.align	5
29NESTED(handle_sys64, PT_SIZE, sp)
30#if !defined(CONFIG_MIPS32_O32) && !defined(CONFIG_MIPS32_N32)
31	/*
32	 * When 32-bit compatibility is configured scall_o32.S
33	 * already did this.
34	 */
35	.set	noat
36	SAVE_SOME
37	TRACE_IRQS_ON_RELOAD
38	STI
39	.set	at
40#endif
41
42#if !defined(CONFIG_MIPS32_O32) && !defined(CONFIG_MIPS32_N32)
43	ld	t1, PT_EPC(sp)		# skip syscall on return
44	daddiu	t1, 4			# skip to next instruction
45	sd	t1, PT_EPC(sp)
46#endif
47
48	sd	a3, PT_R26(sp)		# save a3 for syscall restarting
49
50	li	t1, _TIF_WORK_SYSCALL_ENTRY
51	LONG_L	t0, TI_FLAGS($28)	# syscall tracing enabled?
52	and	t0, t1, t0
53	bnez	t0, syscall_trace_entry
54
55syscall_common:
56	dsubu	t2, v0, __NR_64_Linux
57	sltiu   t0, t2, __NR_64_Linux_syscalls
58	beqz	t0, illegal_syscall
59
60	dsll	t0, t2, 3		# offset into table
61	dla	t2, sys_call_table
62	daddu	t0, t2, t0
63	ld	t2, (t0)		# syscall routine
64	beqz	t2, illegal_syscall
65
66	jalr	t2			# Do The Real Thing (TM)
67
68	li	t0, -EMAXERRNO - 1	# error?
69	sltu	t0, t0, v0
70	sd	t0, PT_R7(sp)		# set error flag
71	beqz	t0, 1f
72
73	ld	t1, PT_R2(sp)		# syscall number
74	dnegu	v0			# error
75	sd	t1, PT_R0(sp)		# save it for syscall restarting
761:	sd	v0, PT_R2(sp)		# result
77
78n64_syscall_exit:
79	j	syscall_exit_partial
80
81/* ------------------------------------------------------------------------ */
82
83syscall_trace_entry:
84	SAVE_STATIC
85	move	a0, sp
86	move	a1, v0
87	jal	syscall_trace_enter
88
89	bltz	v0, 1f			# seccomp failed? Skip syscall
90
91	RESTORE_STATIC
92	ld	v0, PT_R2(sp)		# Restore syscall (maybe modified)
93	ld	a0, PT_R4(sp)		# Restore argument registers
94	ld	a1, PT_R5(sp)
95	ld	a2, PT_R6(sp)
96	ld	a3, PT_R7(sp)
97	ld	a4, PT_R8(sp)
98	ld	a5, PT_R9(sp)
99	j	syscall_common
100
1011:	j	syscall_exit
102
103illegal_syscall:
104	/* This also isn't a 64-bit syscall, throw an error.  */
105	li	v0, ENOSYS			# error
106	sd	v0, PT_R2(sp)
107	li	t0, 1				# set error flag
108	sd	t0, PT_R7(sp)
109	j	n64_syscall_exit
110	END(handle_sys64)
111
112#define __SYSCALL(nr, entry, nargs) PTR entry
113	.align	3
114	.type	sys_call_table, @object
115EXPORT(sys_call_table)
116#include <asm/syscall_table_64_n64.h>
117#undef __SYSCALL
118