1/* 2 * linux/arch/arm/lib/copy_from_user.S 3 * 4 * Author: Nicolas Pitre 5 * Created: Sep 29, 2005 6 * Copyright: MontaVista Software, Inc. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13#include <linux/linkage.h> 14#include <asm/assembler.h> 15 16/* 17 * Prototype: 18 * 19 * size_t __copy_from_user(void *to, const void *from, size_t n) 20 * 21 * Purpose: 22 * 23 * copy a block to kernel memory from user memory 24 * 25 * Params: 26 * 27 * to = kernel memory 28 * from = user memory 29 * n = number of bytes to copy 30 * 31 * Return value: 32 * 33 * Number of bytes NOT copied. 34 */ 35 36#ifndef CONFIG_THUMB2_KERNEL 37#define LDR1W_SHIFT 0 38#else 39#define LDR1W_SHIFT 1 40#endif 41#define STR1W_SHIFT 0 42 43 .macro ldr1w ptr reg abort 44 ldrusr \reg, \ptr, 4, abort=\abort 45 .endm 46 47 .macro ldr4w ptr reg1 reg2 reg3 reg4 abort 48 ldr1w \ptr, \reg1, \abort 49 ldr1w \ptr, \reg2, \abort 50 ldr1w \ptr, \reg3, \abort 51 ldr1w \ptr, \reg4, \abort 52 .endm 53 54 .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort 55 ldr4w \ptr, \reg1, \reg2, \reg3, \reg4, \abort 56 ldr4w \ptr, \reg5, \reg6, \reg7, \reg8, \abort 57 .endm 58 59 .macro ldr1b ptr reg cond=al abort 60 ldrusr \reg, \ptr, 1, \cond, abort=\abort 61 .endm 62 63 .macro str1w ptr reg abort 64 W(str) \reg, [\ptr], #4 65 .endm 66 67 .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort 68 stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8} 69 .endm 70 71 .macro str1b ptr reg cond=al abort 72 str\cond\()b \reg, [\ptr], #1 73 .endm 74 75 .macro enter reg1 reg2 76 mov r3, #0 77 stmdb sp!, {r0, r2, r3, \reg1, \reg2} 78 .endm 79 80 .macro exit reg1 reg2 81 add sp, sp, #8 82 ldmfd sp!, {r0, \reg1, \reg2} 83 .endm 84 85 .text 86 87ENTRY(__copy_from_user) 88 89#include "copy_template.S" 90 91ENDPROC(__copy_from_user) 92 93 .pushsection .fixup,"ax" 94 .align 0 95 copy_abort_preamble 96 ldmfd sp!, {r1, r2} 97 sub r3, r0, r1 98 rsb r1, r3, r2 99 str r1, [sp] 100 bl __memzero 101 ldr r0, [sp], #4 102 copy_abort_end 103 .popsection 104