xref: /freebsd/sys/arm/arm/copystr.S (revision e0c4386e)
1/*	$NetBSD: copystr.S,v 1.8 2002/10/13 14:54:48 bjh21 Exp $	*/
2
3/*-
4 * Copyright (c) 1995 Mark Brinicombe.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by Mark Brinicombe.
18 * 4. The name of the company nor the name of the author may be used to
19 *    endorse or promote products derived from this software without specific
20 *    prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
26 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
27 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
28 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * copystr.S
35 *
36 * optimised and fault protected copystr functions
37 *
38 * Created      : 16/05/95
39 */
40
41#include "assym.inc"
42#include <machine/asm.h>
43#include <machine/armreg.h>
44#include <sys/errno.h>
45
46	.text
47	.align	2
48
49#define GET_PCB(tmp) \
50	mrc p15, 0, tmp, c13, c0, 4; \
51	add	tmp, tmp, #(TD_PCB)
52
53#define SAVE_REGS	stmfd	sp!, {r4-r6}
54#define RESTORE_REGS	ldmfd	sp!, {r4-r6}
55
56/*
57 * r0 - user space address
58 * r1 - kernel space address
59 * r2 - maxlens
60 * r3 - lencopied
61 *
62 * Copy string from user space to kernel space
63 */
64ENTRY(copyinstr)
65	SAVE_REGS
66
67	teq	r2, #0x00000000
68	mov	r6, #0x00000000
69	moveq	r0, #ENAMETOOLONG
70	beq	2f
71
72	ldr	r12, =VM_MAXUSER_ADDRESS
73
74	GET_PCB(r4)
75	ldr	r4, [r4]
76
77#ifdef DIAGNOSTIC
78	teq	r4, #0x00000000
79	beq	.Lcopystrpcbfault
80#endif
81
82	adr	r5, .Lcopystrfault
83	str	r5, [r4, #PCB_ONFAULT]
84
851:
86	cmp	r0, r12
87	bcs	.Lcopystrfault
88	ldrbt	r5, [r0], #0x0001
89	add	r6, r6, #0x00000001
90	teq	r5, #0x00000000
91	strb	r5, [r1], #0x0001
92	teqne	r6, r2
93	bne	1b
94
95	mov	r0, #0x00000000
96	str	r0, [r4, #PCB_ONFAULT]
97
98	teq	r5, #0x00000000
99	moveq	r0, #0x00000000
100	movne	r0, #ENAMETOOLONG
101
1022:	teq	r3, #0x00000000
103	strne	r6, [r3]
104
105	RESTORE_REGS
106	RET
107END(copyinstr)
108
109/* A fault occurred during the copy */
110.Lcopystrfault:
111	mov	r1, #0x00000000
112	str	r1, [r4, #PCB_ONFAULT]
113	mov	r0, #EFAULT
114	RESTORE_REGS
115	RET
116
117#ifdef DIAGNOSTIC
118.Lcopystrpcbfault:
119	mov	r2, r1
120	mov	r1, r0
121	adr	r0, Lcopystrpcbfaulttext
122	bic	sp, sp, #7			/* align stack to 8 bytes */
123	b	_C_LABEL(panic)
124
125Lcopystrpcbfaulttext:
126	.asciz	"No valid PCB during copyinoutstr() addr1=%08x addr2=%08x\n"
127	.align	2
128#endif
129