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#if __LINUX_ARM_ARCH__ >= 6 45 462: TUSER(strh) r2, [r0] 47 48#else 49 50 mov ip, r2, lsr #8 51#ifndef __ARMEB__ 522: TUSER(strb) r2, [r0], #1 533: TUSER(strb) ip, [r0] 54#else 552: TUSER(strb) ip, [r0], #1 563: TUSER(strb) r2, [r0] 57#endif 58 59#endif /* __LINUX_ARM_ARCH__ >= 6 */ 60 mov r0, #0 61 ret lr 62ENDPROC(__put_user_2) 63 64ENTRY(__put_user_4) 65 check_uaccess r0, 4, r1, ip, __put_user_bad 664: TUSER(str) r2, [r0] 67 mov r0, #0 68 ret lr 69ENDPROC(__put_user_4) 70 71ENTRY(__put_user_8) 72 check_uaccess r0, 8, r1, ip, __put_user_bad 73#ifdef CONFIG_THUMB2_KERNEL 745: TUSER(str) r2, [r0] 756: TUSER(str) r3, [r0, #4] 76#else 775: TUSER(str) r2, [r0], #4 786: TUSER(str) r3, [r0] 79#endif 80 mov r0, #0 81 ret lr 82ENDPROC(__put_user_8) 83 84__put_user_bad: 85 mov r0, #-EFAULT 86 ret lr 87ENDPROC(__put_user_bad) 88 89.pushsection __ex_table, "a" 90 .long 1b, __put_user_bad 91 .long 2b, __put_user_bad 92#if __LINUX_ARM_ARCH__ < 6 93 .long 3b, __put_user_bad 94#endif 95 .long 4b, __put_user_bad 96 .long 5b, __put_user_bad 97 .long 6b, __put_user_bad 98.popsection 99