linux-stable/arch/arm64/lib/clear_page.S
Will Deacon 8d9902055c arm64: lib: Annotate {clear, copy}_page() as position-independent
clear_page() and copy_page() are suitable for use outside of the kernel
address space, so annotate them as position-independent code.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210319100146.1149909-2-qperret@google.com
2021-03-19 12:01:19 +00:00

29 lines
463 B
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
*/
#include <linux/linkage.h>
#include <linux/const.h>
#include <asm/assembler.h>
#include <asm/page.h>
/*
* Clear page @dest
*
* Parameters:
* x0 - dest
*/
SYM_FUNC_START_PI(clear_page)
mrs x1, dczid_el0
and w1, w1, #0xf
mov x2, #4
lsl x1, x2, x1
1: dc zva, x0
add x0, x0, x1
tst x0, #(PAGE_SIZE - 1)
b.ne 1b
ret
SYM_FUNC_END_PI(clear_page)
EXPORT_SYMBOL(clear_page)