linux_dsm_epyc7002/arch/arm/lib/getuser.S
Russell King 8478132a87 Revert "arm: move exports to definitions"
This reverts commit 4dd1837d75.

Moving the exports for assembly code into the assembly files breaks
KSYM trimming, but also breaks modversions.

While fixing the KSYM trimming is trivial, fixing modversions brings
us to a technically worse position that we had prior to the above
change:

- We end up with the prototype definitions divorsed from everything
  else, which means that adding or removing assembly level ksyms
  become more fragile:
  * if adding a new assembly ksyms export, a missed prototype in
    asm-prototypes.h results in a successful build if no module in
    the selected configuration makes use of the symbol.
  * when removing a ksyms export, asm-prototypes.h will get forgotten,
    with armksyms.c, you'll get a build error if you forget to touch
    the file.

- We end up with the same amount of include files and prototypes,
  they're just in a header file instead of a .c file with their
  exports.

As for lines of code, we don't get much of a size reduction:
 (original commit)
 47 files changed, 131 insertions(+), 208 deletions(-)
 (fix for ksyms trimming)
 7 files changed, 18 insertions(+), 5 deletions(-)
 (two fixes for modversions)
 1 file changed, 34 insertions(+)
 3 files changed, 7 insertions(+), 2 deletions(-)
which results in a net total of only 25 lines deleted.

As there does not seem to be much benefit from this change of approach,
revert the change.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-11-23 10:00:03 +00:00

150 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