diff options
Diffstat (limited to 'arch/arm/lib/copy_from_user.S')
| -rw-r--r-- | arch/arm/lib/copy_from_user.S | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/arm/lib/copy_from_user.S b/arch/arm/lib/copy_from_user.S new file mode 100644 index 00000000..66a477a3 --- /dev/null +++ b/arch/arm/lib/copy_from_user.S @@ -0,0 +1,104 @@ +/* + * linux/arch/arm/lib/copy_from_user.S + * + * Author: Nicolas Pitre + * Created: Sep 29, 2005 + * Copyright: MontaVista Software, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/linkage.h> +#include <asm/assembler.h> + +/* + * Prototype: + * + * size_t __copy_from_user(void *to, const void *from, size_t n) + * + * Purpose: + * + * copy a block to kernel memory from user memory + * + * Params: + * + * to = kernel memory + * from = user memory + * n = number of bytes to copy + * + * Return value: + * + * Number of bytes NOT copied. + */ + +#ifndef CONFIG_THUMB2_KERNEL +#define LDR1W_SHIFT 0 +#else +#define LDR1W_SHIFT 1 +#endif +#define STR1W_SHIFT 0 + + .macro ldr1w ptr reg abort + ldrusr \reg, \ptr, 4, abort=\abort + .endm + + .macro ldr4w ptr reg1 reg2 reg3 reg4 abort + ldr1w \ptr, \reg1, \abort + ldr1w \ptr, \reg2, \abort + ldr1w \ptr, \reg3, \abort + ldr1w \ptr, \reg4, \abort + .endm + + .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort + ldr4w \ptr, \reg1, \reg2, \reg3, \reg4, \abort + ldr4w \ptr, \reg5, \reg6, \reg7, \reg8, \abort + .endm + + .macro ldr1b ptr reg cond=al abort + ldrusr \reg, \ptr, 1, \cond, abort=\abort + .endm + + .macro str1w ptr reg abort + W(str) \reg, [\ptr], #4 + .endm + + .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort + stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8} + .endm + + .macro str1b ptr reg cond=al abort + str\cond\()b \reg, [\ptr], #1 + .endm + + .macro enter reg1 reg2 + mov r3, #0 + stmdb sp!, {r0, r2, r3, \reg1, \reg2} + .endm + + .macro exit reg1 reg2 + add sp, sp, #8 + ldmfd sp!, {r0, \reg1, \reg2} + .endm + + .text + +ENTRY(__copy_from_user) + +#include "copy_template.S" + +ENDPROC(__copy_from_user) + + .pushsection .fixup,"ax" + .align 0 + copy_abort_preamble + ldmfd sp!, {r1, r2} + sub r3, r0, r1 + rsb r1, r3, r2 + str r1, [sp] + bl __memzero + ldr r0, [sp], #4 + copy_abort_end + .popsection + |