1/* 2 * linux/arch/arm/lib/putuser.S 3 * 4 * Copyright (C) 2001 Russell King 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 * Idea from x86 version, (C) Copyright 1998 Linus Torvalds 11 * 12 * These functions have a non-standard call interface to make 13 * them more efficient, especially as they return an error 14 * value in addition to the "real" return value. 15 * 16 * __put_user_X 17 * 18 * Inputs: r0 contains the address 19 * r2, r3 contains the value 20 * Outputs: r0 is the error code 21 * lr corrupted 22 * 23 * No other registers must be altered. (see include/asm-arm/uaccess.h 24 * for specific ASM register usage). 25 * 26 * Note that ADDR_LIMIT is either 0 or 0xc0000000 27 * Note also that it is intended that __put_user_bad is not global. 28 */ 29#include <asm/constants.h> 30#include <asm/thread_info.h> 31#include <asm/errno.h> 32 33 .global __put_user_1 34__put_user_1: 351: strbt r2, [r0] 36 mov r0, #0 37 mov pc, lr 38 39 .global __put_user_2 40__put_user_2: 41 mov ip, r2, lsr #8 42#ifndef __ARMEB__ 432: strbt r2, [r0], #1 443: strbt ip, [r0] 45#else 462: strbt ip, [r0], #1 473: strbt r2, [r0] 48#endif 49 mov r0, #0 50 mov pc, lr 51 52 .global __put_user_4 53__put_user_4: 544: strt r2, [r0] 55 mov r0, #0 56 mov pc, lr 57 58 .global __put_user_8 59__put_user_8: 605: strt r2, [r0], #4 616: strt r3, [r0] 62 mov r0, #0 63 mov pc, lr 64 65__put_user_bad: 66 mov r0, #-EFAULT 67 mov pc, lr 68 69.section __ex_table, "a" 70 .long 1b, __put_user_bad 71 .long 2b, __put_user_bad 72 .long 3b, __put_user_bad 73 .long 4b, __put_user_bad 74 .long 5b, __put_user_bad 75 .long 6b, __put_user_bad 76.previous 77