mirror_ubuntu-kernels/arch/arm/lib/copy_to_user.S

126 lines
2.3 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* linux/arch/arm/lib/copy_to_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_to_user(void *to, const void *from, size_t n)
*
* Purpose:
*
* copy a block to user memory from kernel memory
*
* Params:
*
* to = user memory
* from = kernel memory
* n = number of bytes to copy
*
* Return value:
*
* Number of bytes NOT copied.
*/
#define LDR1W_SHIFT 0
.macro ldr1w ptr reg abort
W(ldr) \reg, [\ptr], #4
.endm
.macro ldr4w ptr reg1 reg2 reg3 reg4 abort
ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}
.endm
.macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
.endm
.macro ldr1b ptr reg cond=al abort
ldrb\cond \reg, [\ptr], #1
.endm
#ifdef CONFIG_CPU_USE_DOMAINS
#ifndef CONFIG_THUMB2_KERNEL
#define STR1W_SHIFT 0
#else
#define STR1W_SHIFT 1
#endif
.macro str1w ptr reg abort
strusr \reg, \ptr, 4, abort=\abort
.endm
.macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
str1w \ptr, \reg1, \abort
str1w \ptr, \reg2, \abort
str1w \ptr, \reg3, \abort
str1w \ptr, \reg4, \abort
str1w \ptr, \reg5, \abort
str1w \ptr, \reg6, \abort
str1w \ptr, \reg7, \abort
str1w \ptr, \reg8, \abort
.endm
#else
#define STR1W_SHIFT 0
.macro str1w ptr reg abort
USERL(\abort, W(str) \reg, [\ptr], #4)
.endm
.macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
USERL(\abort, stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8})
.endm
#endif /* CONFIG_CPU_USE_DOMAINS */
.macro str1b ptr reg cond=al abort
strusr \reg, \ptr, 1, \cond, abort=\abort
.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(__copy_to_user_std)
WEAK(arm_copy_to_user)
#ifdef CONFIG_CPU_SPECTRE
ldr r3, =TASK_SIZE
uaccess_mask_range_ptr r0, r2, r3, ip
#endif
#include "copy_template.S"
ENDPROC(arm_copy_to_user)
ENDPROC(__copy_to_user_std)
.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