| /* |
| * linux/arch/arm/lib/getuser.S |
| * |
| * Copyright (C) 2001 Russell King |
| * |
| * 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. |
| * |
| * 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. |
| * |
| * __get_user_X |
| * |
| * Inputs: r0 contains the address |
| * r1 contains the address limit, which must be preserved |
| * Outputs: r0 is the error code |
| * r2, r3 contains the zero-extended value |
| * 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 __get_user_bad is not global. |
| */ |
| #include <linux/linkage.h> |
| #include <asm/assembler.h> |
| #include <asm/errno.h> |
| #include <asm/domain.h> |
| |
| ENTRY(__get_user_1) |
| check_uaccess r0, 1, r1, r2, __get_user_bad |
| 1: TUSER(ldrb) r2, [r0] |
| mov r0, #0 |
| ret lr |
| ENDPROC(__get_user_1) |
| |
| ENTRY(__get_user_2) |
| check_uaccess r0, 2, r1, r2, __get_user_bad |
| #ifdef CONFIG_CPU_USE_DOMAINS |
| rb .req ip |
| 2: ldrbt r2, [r0], #1 |
| 3: ldrbt rb, [r0], #0 |
| #else |
| rb .req r0 |
| 2: ldrb r2, [r0] |
| 3: ldrb rb, [r0, #1] |
| #endif |
| #ifndef __ARMEB__ |
| orr r2, r2, rb, lsl #8 |
| #else |
| orr r2, rb, r2, lsl #8 |
| #endif |
| mov r0, #0 |
| ret lr |
| ENDPROC(__get_user_2) |
| |
| ENTRY(__get_user_4) |
| check_uaccess r0, 4, r1, r2, __get_user_bad |
| 4: TUSER(ldr) r2, [r0] |
| mov r0, #0 |
| ret lr |
| ENDPROC(__get_user_4) |
| |
| ENTRY(__get_user_8) |
| check_uaccess r0, 8, r1, r2, __get_user_bad |
| #ifdef CONFIG_THUMB2_KERNEL |
| 5: TUSER(ldr) r2, [r0] |
| 6: TUSER(ldr) r3, [r0, #4] |
| #else |
| 5: TUSER(ldr) r2, [r0], #4 |
| 6: TUSER(ldr) r3, [r0] |
| #endif |
| mov r0, #0 |
| ret lr |
| ENDPROC(__get_user_8) |
| |
| #ifdef __ARMEB__ |
| ENTRY(__get_user_lo8) |
| check_uaccess r0, 8, r1, r2, __get_user_bad |
| #ifdef CONFIG_CPU_USE_DOMAINS |
| add r0, r0, #4 |
| 7: ldrt r2, [r0] |
| #else |
| 7: ldr r2, [r0, #4] |
| #endif |
| mov r0, #0 |
| ret lr |
| ENDPROC(__get_user_lo8) |
| #endif |
| |
| __get_user_bad8: |
| mov r3, #0 |
| __get_user_bad: |
| mov r2, #0 |
| mov r0, #-EFAULT |
| ret lr |
| ENDPROC(__get_user_bad) |
| ENDPROC(__get_user_bad8) |
| |
| .pushsection __ex_table, "a" |
| .long 1b, __get_user_bad |
| .long 2b, __get_user_bad |
| .long 3b, __get_user_bad |
| .long 4b, __get_user_bad |
| .long 5b, __get_user_bad8 |
| .long 6b, __get_user_bad8 |
| #ifdef __ARMEB__ |
| .long 7b, __get_user_bad |
| #endif |
| .popsection |