d9981380b4
e38361d'ARM: 8091/2: add get_user() support for 8 byte types' commit broke V7 BE get_user call when target var size is 64 bit, but '*ptr' size is 32 bit or smaller.e38361dchanged type of __r2 from 'register unsigned long' to 'register typeof(x) __r2 asm("r2")' i.e before the change even when target variable size was 64 bit, __r2 was still 32 bit. But aftere38361dcommit, for target var of 64 bit size, __r2 became 64 bit and now it should occupy 2 registers r2, and r3. The issue in BE case that r3 register is least significant word of __r2 and r2 register is most significant word of __r2. But __get_user_4 still copies result into r2 (most significant word of __r2). Subsequent code copies from __r2 into x, but for situation described it will pick up only garbage from r3 register. Special __get_user_64t_(124) functions are introduced. They are similar to corresponding __get_user_(124) function but result stored in r3 register (lsw in case of 64 bit __r2 in BE image). Those function are used by get_user macro in case of BE and target var size is 64bit. Also changed __get_user_lo8 name into __get_user_32t_8 to get consistent naming accross all cases. Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org> Suggested-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
149 lines
3.1 KiB
ArmAsm
149 lines
3.1 KiB
ArmAsm
/*
|
|
* 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_32t_8)
|
|
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_32t_8)
|
|
|
|
ENTRY(__get_user_64t_1)
|
|
check_uaccess r0, 1, r1, r2, __get_user_bad8
|
|
8: TUSER(ldrb) r3, [r0]
|
|
mov r0, #0
|
|
ret lr
|
|
ENDPROC(__get_user_64t_1)
|
|
|
|
ENTRY(__get_user_64t_2)
|
|
check_uaccess r0, 2, r1, r2, __get_user_bad8
|
|
#ifdef CONFIG_CPU_USE_DOMAINS
|
|
rb .req ip
|
|
9: ldrbt r3, [r0], #1
|
|
10: ldrbt rb, [r0], #0
|
|
#else
|
|
rb .req r0
|
|
9: ldrb r3, [r0]
|
|
10: ldrb rb, [r0, #1]
|
|
#endif
|
|
orr r3, rb, r3, lsl #8
|
|
mov r0, #0
|
|
ret lr
|
|
ENDPROC(__get_user_64t_2)
|
|
|
|
ENTRY(__get_user_64t_4)
|
|
check_uaccess r0, 4, r1, r2, __get_user_bad8
|
|
11: TUSER(ldr) r3, [r0]
|
|
mov r0, #0
|
|
ret lr
|
|
ENDPROC(__get_user_64t_4)
|
|
#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
|
|
.long 8b, __get_user_bad8
|
|
.long 9b, __get_user_bad8
|
|
.long 10b, __get_user_bad8
|
|
.long 11b, __get_user_bad8
|
|
#endif
|
|
.popsection
|