1/*
2 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
3 *
4 *  Copyright (C) 2004  Randolph Chung <tausq@debian.org>
5 *
6 *    This program is free software; you can redistribute it and/or modify
7 *    it under the terms of the GNU General Public License as published by
8 *    the Free Software Foundation; either version 2, or (at your option)
9 *    any later version.
10 *
11 *    This program is distributed in the hope that it will be useful,
12 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
13 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 *    GNU General Public License for more details.
15 *
16 *    You should have received a copy of the GNU General Public License
17 *    along with this program; if not, write to the Free Software
18 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 *
20 * Fixup routines for kernel exception handling.
21 */
22#include <asm/asm-offsets.h>
23#include <asm/assembly.h>
24#include <asm/errno.h>
25#include <linux/linkage.h>
26
27#ifdef CONFIG_SMP
28	.macro  get_fault_ip t1 t2
29	loadgp
30	addil LT%__per_cpu_offset,%r27
31	LDREG RT%__per_cpu_offset(%r1),\t1
32	/* t2 = smp_processor_id() */
33	mfctl 30,\t2
34	ldw TI_CPU(\t2),\t2
35#ifdef CONFIG_64BIT
36	extrd,u \t2,63,32,\t2
37#endif
38	/* t2 = &__per_cpu_offset[smp_processor_id()]; */
39	LDREGX \t2(\t1),\t2
40	addil LT%exception_data,%r27
41	LDREG RT%exception_data(%r1),\t1
42	/* t1 = this_cpu_ptr(&exception_data) */
43	add,l \t1,\t2,\t1
44	/* %r27 = t1->fault_gp - restore gp */
45	LDREG EXCDATA_GP(\t1), %r27
46	/* t1 = t1->fault_ip */
47	LDREG EXCDATA_IP(\t1), \t1
48	.endm
49#else
50	.macro  get_fault_ip t1 t2
51	loadgp
52	/* t1 = this_cpu_ptr(&exception_data) */
53	addil LT%exception_data,%r27
54	LDREG RT%exception_data(%r1),\t2
55	/* %r27 = t2->fault_gp - restore gp */
56	LDREG EXCDATA_GP(\t2), %r27
57	/* t1 = t2->fault_ip */
58	LDREG EXCDATA_IP(\t2), \t1
59	.endm
60#endif
61
62	.level LEVEL
63
64	.text
65	.section .fixup, "ax"
66
67	/* get_user() fixups, store -EFAULT in r8, and 0 in r9 */
68ENTRY(fixup_get_user_skip_1)
69	get_fault_ip %r1,%r8
70	ldo 4(%r1), %r1
71	ldi -EFAULT, %r8
72	bv %r0(%r1)
73	copy %r0, %r9
74ENDPROC(fixup_get_user_skip_1)
75
76ENTRY(fixup_get_user_skip_2)
77	get_fault_ip %r1,%r8
78	ldo 8(%r1), %r1
79	ldi -EFAULT, %r8
80	bv %r0(%r1)
81	copy %r0, %r9
82ENDPROC(fixup_get_user_skip_2)
83
84	/* put_user() fixups, store -EFAULT in r8 */
85ENTRY(fixup_put_user_skip_1)
86	get_fault_ip %r1,%r8
87	ldo 4(%r1), %r1
88	bv %r0(%r1)
89	ldi -EFAULT, %r8
90ENDPROC(fixup_put_user_skip_1)
91
92ENTRY(fixup_put_user_skip_2)
93	get_fault_ip %r1,%r8
94	ldo 8(%r1), %r1
95	bv %r0(%r1)
96	ldi -EFAULT, %r8
97ENDPROC(fixup_put_user_skip_2)
98
99