1/* 2 * linux/arch/arm/lib/putuser.S 3 * 4 * Copyright (C) 2001 Russell King 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 version 2 as 8 * published by the Free Software Foundation. 9 * 10 * Idea from x86 version, (C) Copyright 1998 Linus Torvalds 11 * 12 * These functions have a non-standard call interface to make 13 * them more efficient, especially as they return an error 14 * value in addition to the "real" return value. 15 * 16 * __put_user_X 17 * 18 * Inputs: r0 contains the address 19 * r1 contains the address limit, which must be preserved 20 * r2, r3 contains the value 21 * Outputs: r0 is the error code 22 * lr corrupted 23 * 24 * No other registers must be altered. (see <asm/uaccess.h> 25 * for specific ASM register usage). 26 * 27 * Note that ADDR_LIMIT is either 0 or 0xc0000000 28 * Note also that it is intended that __put_user_bad is not global. 29 */ 30#include <linux/linkage.h> 31#include <asm/assembler.h> 32#include <asm/errno.h> 33#include <asm/domain.h> 34 35ENTRY(__put_user_1) 36 check_uaccess r0, 1, r1, ip, __put_user_bad 371: TUSER(strb) r2, [r0] 38 mov r0, #0 39 ret lr 40ENDPROC(__put_user_1) 41 42ENTRY(__put_user_2) 43 check_uaccess r0, 2, r1, ip, __put_user_bad 44 mov ip, r2, lsr #8 45#ifdef CONFIG_THUMB2_KERNEL 46#ifndef __ARMEB__ 472: TUSER(strb) r2, [r0] 483: TUSER(strb) ip, [r0, #1] 49#else 502: TUSER(strb) ip, [r0] 513: TUSER(strb) r2, [r0, #1] 52#endif 53#else /* !CONFIG_THUMB2_KERNEL */ 54#ifndef __ARMEB__ 552: TUSER(strb) r2, [r0], #1 563: TUSER(strb) ip, [r0] 57#else 582: TUSER(strb) ip, [r0], #1 593: TUSER(strb) r2, [r0] 60#endif 61#endif /* CONFIG_THUMB2_KERNEL */ 62 mov r0, #0 63 ret lr 64ENDPROC(__put_user_2) 65 66ENTRY(__put_user_4) 67 check_uaccess r0, 4, r1, ip, __put_user_bad 684: TUSER(str) r2, [r0] 69 mov r0, #0 70 ret lr 71ENDPROC(__put_user_4) 72 73ENTRY(__put_user_8) 74 check_uaccess r0, 8, r1, ip, __put_user_bad 75#ifdef CONFIG_THUMB2_KERNEL 765: TUSER(str) r2, [r0] 776: TUSER(str) r3, [r0, #4] 78#else 795: TUSER(str) r2, [r0], #4 806: TUSER(str) r3, [r0] 81#endif 82 mov r0, #0 83 ret lr 84ENDPROC(__put_user_8) 85 86__put_user_bad: 87 mov r0, #-EFAULT 88 ret lr 89ENDPROC(__put_user_bad) 90 91.pushsection __ex_table, "a" 92 .long 1b, __put_user_bad 93 .long 2b, __put_user_bad 94 .long 3b, __put_user_bad 95 .long 4b, __put_user_bad 96 .long 5b, __put_user_bad 97 .long 6b, __put_user_bad 98.popsection 99