0f61f6be1f
Now that we have SYM_FUNC_ALIAS() and SYM_FUNC_ALIAS_WEAK(), use those
to simplify and more consistently define function aliases across
arch/arm64.
Aliases are now defined in terms of a canonical function name. For
position-independent functions I've made the __pi_<func> name the
canonical name, and defined other alises in terms of this.
The SYM_FUNC_{START,END}_PI(func) macros obscure the __pi_<func> name,
and make this hard to seatch for. The SYM_FUNC_START_WEAK_PI() macro
also obscures the fact that the __pi_<func> fymbol is global and the
<func> symbol is weak. For clarity, I have removed these macros and used
SYM_FUNC_{START,END}() directly with the __pi_<func> name.
For example:
SYM_FUNC_START_WEAK_PI(func)
... asm insns ...
SYM_FUNC_END_PI(func)
EXPORT_SYMBOL(func)
... becomes:
SYM_FUNC_START(__pi_func)
... asm insns ...
SYM_FUNC_END(__pi_func)
SYM_FUNC_ALIAS_WEAK(func, __pi_func)
EXPORT_SYMBOL(func)
For clarity, where there are multiple annotations such as
EXPORT_SYMBOL(), I've tried to keep annotations grouped by symbol. For
example, where a function has a name and an alias which are both
exported, this is organised as:
SYM_FUNC_START(func)
... asm insns ...
SYM_FUNC_END(func)
EXPORT_SYMBOL(func)
SYM_FUNC_ALIAS(alias, func)
EXPORT_SYMBOL(alias)
For consistency with the other string functions, I've defined strrchr as
a position-independent function, as it can safely be used as such even
though we have no users today.
As we no longer use SYM_FUNC_{START,END}_ALIAS(), our local copies are
removed. The common versions will be removed by a subsequent patch.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220216162229.1076788-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
35 lines
643 B
ArmAsm
35 lines
643 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Based on arch/arm/lib/strchr.S
|
|
*
|
|
* Copyright (C) 1995-2000 Russell King
|
|
* Copyright (C) 2013 ARM Ltd.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/assembler.h>
|
|
|
|
/*
|
|
* Find the first occurrence of a character in a string.
|
|
*
|
|
* Parameters:
|
|
* x0 - str
|
|
* x1 - c
|
|
* Returns:
|
|
* x0 - address of first occurrence of 'c' or 0
|
|
*/
|
|
SYM_FUNC_START(__pi_strchr)
|
|
and w1, w1, #0xff
|
|
1: ldrb w2, [x0], #1
|
|
cmp w2, w1
|
|
ccmp w2, wzr, #4, ne
|
|
b.ne 1b
|
|
sub x0, x0, #1
|
|
cmp w2, w1
|
|
csel x0, x0, xzr, eq
|
|
ret
|
|
SYM_FUNC_END(__pi_strchr)
|
|
|
|
SYM_FUNC_ALIAS_WEAK(strchr, __pi_strchr)
|
|
EXPORT_SYMBOL_NOKASAN(strchr)
|