| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* |
| * linux/arch/arm/lib/putuser.S |
| * |
| * Copyright (C) 2001 Russell King |
| * |
| * Idea from x86 version, (C) Copyright 1998 Linus Torvalds |
| * |
| * These functions have a non-standard call interface to make |
| * them more efficient, especially as they return an error |
| * value in addition to the "real" return value. |
| * |
| * __put_user_X |
| * |
| * Inputs: r0 contains the address |
| * r1 contains the address limit, which must be preserved |
| * r2, r3 contains the value |
| * Outputs: r0 is the error code |
| * lr corrupted |
| * |
| * No other registers must be altered. (see <asm/uaccess.h> |
| * for specific ASM register usage). |
| * |
| * Note that ADDR_LIMIT is either 0 or 0xc0000000 |
| * Note also that it is intended that __put_user_bad is not global. |
| */ |
| #include <linux/linkage.h> |
| #include <asm/assembler.h> |
| #include <asm/errno.h> |
| #include <asm/domain.h> |
| |
| ENTRY(__put_user_1) |
| check_uaccess r0, 1, r1, ip, __put_user_bad |
| 1: TUSER(strb) r2, [r0] |
| mov r0, #0 |
| ret lr |
| ENDPROC(__put_user_1) |
| |
| ENTRY(__put_user_2) |
| check_uaccess r0, 2, r1, ip, __put_user_bad |
| #if __LINUX_ARM_ARCH__ >= 6 |
| |
| 2: TUSER(strh) r2, [r0] |
| |
| #else |
| |
| mov ip, r2, lsr #8 |
| #ifndef __ARMEB__ |
| 2: TUSER(strb) r2, [r0], #1 |
| 3: TUSER(strb) ip, [r0] |
| #else |
| 2: TUSER(strb) ip, [r0], #1 |
| 3: TUSER(strb) r2, [r0] |
| #endif |
| |
| #endif /* __LINUX_ARM_ARCH__ >= 6 */ |
| mov r0, #0 |
| ret lr |
| ENDPROC(__put_user_2) |
| |
| ENTRY(__put_user_4) |
| check_uaccess r0, 4, r1, ip, __put_user_bad |
| 4: TUSER(str) r2, [r0] |
| mov r0, #0 |
| ret lr |
| ENDPROC(__put_user_4) |
| |
| ENTRY(__put_user_8) |
| check_uaccess r0, 8, r1, ip, __put_user_bad |
| #ifdef CONFIG_THUMB2_KERNEL |
| 5: TUSER(str) r2, [r0] |
| 6: TUSER(str) r3, [r0, #4] |
| #else |
| 5: TUSER(str) r2, [r0], #4 |
| 6: TUSER(str) r3, [r0] |
| #endif |
| mov r0, #0 |
| ret lr |
| ENDPROC(__put_user_8) |
| |
| __put_user_bad: |
| mov r0, #-EFAULT |
| ret lr |
| ENDPROC(__put_user_bad) |
| |
| .pushsection __ex_table, "a" |
| .long 1b, __put_user_bad |
| .long 2b, __put_user_bad |
| #if __LINUX_ARM_ARCH__ < 6 |
| .long 3b, __put_user_bad |
| #endif |
| .long 4b, __put_user_bad |
| .long 5b, __put_user_bad |
| .long 6b, __put_user_bad |
| .popsection |
