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Diffstat (limited to 'arch/arm/lib/copy_from_user.S')
-rw-r--r-- | arch/arm/lib/copy_from_user.S | 125 |
1 files changed, 125 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 0000000000..270de7debd --- /dev/null +++ b/arch/arm/lib/copy_from_user.S @@ -0,0 +1,125 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/lib/copy_from_user.S + * + * Author: Nicolas Pitre + * Created: Sep 29, 2005 + * Copyright: MontaVista Software, Inc. + */ + +#include <linux/linkage.h> +#include <asm/assembler.h> +#include <asm/unwind.h> + +/* + * Prototype: + * + * size_t arm_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. + */ + +#ifdef CONFIG_CPU_USE_DOMAINS + +#ifndef CONFIG_THUMB2_KERNEL +#define LDR1W_SHIFT 0 +#else +#define LDR1W_SHIFT 1 +#endif + + .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 + +#else + +#define LDR1W_SHIFT 0 + + .macro ldr1w ptr reg abort + USERL(\abort, W(ldr) \reg, [\ptr], #4) + .endm + + .macro ldr4w ptr reg1 reg2 reg3 reg4 abort + USERL(\abort, ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}) + .endm + + .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort + USERL(\abort, ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}) + .endm + +#endif /* CONFIG_CPU_USE_DOMAINS */ + + .macro ldr1b ptr reg cond=al abort + ldrusr \reg, \ptr, 1, \cond, abort=\abort + .endm + +#define STR1W_SHIFT 0 + + .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 + strb\cond \reg, [\ptr], #1 + .endm + + .macro enter regs:vararg + mov r3, #0 +UNWIND( .save {r0, r2, r3, \regs} ) + stmdb sp!, {r0, r2, r3, \regs} + .endm + + .macro exit regs:vararg + add sp, sp, #8 + ldmfd sp!, {r0, \regs} + .endm + + .text + +ENTRY(arm_copy_from_user) +#ifdef CONFIG_CPU_SPECTRE + ldr r3, =TASK_SIZE + uaccess_mask_range_ptr r1, r2, r3, ip +#endif + +#include "copy_template.S" + +ENDPROC(arm_copy_from_user) + + .pushsection .text.fixup,"ax" + .align 0 + copy_abort_preamble + ldmfd sp!, {r1, r2, r3} + sub r0, r0, r1 + rsb r0, r0, r2 + copy_abort_end + .popsection + |