forked from mirrors/linux
		
	Based on 2 normalized pattern(s): 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 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 # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			85 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			85 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-only
 | 
						|
/*
 | 
						|
 *  linux/arch/arm/mm/copypage-v4wt.S
 | 
						|
 *
 | 
						|
 *  Copyright (C) 1995-1999 Russell King
 | 
						|
 *
 | 
						|
 *  This is for CPUs with a writethrough cache and 'flush ID cache' is
 | 
						|
 *  the only supported cache operation.
 | 
						|
 */
 | 
						|
#include <linux/init.h>
 | 
						|
#include <linux/highmem.h>
 | 
						|
 | 
						|
/*
 | 
						|
 * ARMv4 optimised copy_user_highpage
 | 
						|
 *
 | 
						|
 * Since we have writethrough caches, we don't have to worry about
 | 
						|
 * dirty data in the cache.  However, we do have to ensure that
 | 
						|
 * subsequent reads are up to date.
 | 
						|
 */
 | 
						|
static void v4wt_copy_user_page(void *kto, const void *kfrom)
 | 
						|
{
 | 
						|
	int tmp;
 | 
						|
 | 
						|
	asm volatile ("\
 | 
						|
	.syntax unified\n\
 | 
						|
	ldmia	%1!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
1:	stmia	%0!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
	ldmia	%1!, {r3, r4, ip, lr}		@ 4+1\n\
 | 
						|
	stmia	%0!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
	ldmia	%1!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
	stmia	%0!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
	ldmia	%1!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
	subs	%2, %2, #1			@ 1\n\
 | 
						|
	stmia	%0!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
	ldmiane	%1!, {r3, r4, ip, lr}		@ 4\n\
 | 
						|
	bne	1b				@ 1\n\
 | 
						|
	mcr	p15, 0, %2, c7, c7, 0		@ flush ID cache"
 | 
						|
	: "+&r" (kto), "+&r" (kfrom), "=&r" (tmp)
 | 
						|
	: "2" (PAGE_SIZE / 64)
 | 
						|
	: "r3", "r4", "ip", "lr");
 | 
						|
}
 | 
						|
 | 
						|
void v4wt_copy_user_highpage(struct page *to, struct page *from,
 | 
						|
	unsigned long vaddr, struct vm_area_struct *vma)
 | 
						|
{
 | 
						|
	void *kto, *kfrom;
 | 
						|
 | 
						|
	kto = kmap_atomic(to);
 | 
						|
	kfrom = kmap_atomic(from);
 | 
						|
	v4wt_copy_user_page(kto, kfrom);
 | 
						|
	kunmap_atomic(kfrom);
 | 
						|
	kunmap_atomic(kto);
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * ARMv4 optimised clear_user_page
 | 
						|
 *
 | 
						|
 * Same story as above.
 | 
						|
 */
 | 
						|
void v4wt_clear_user_highpage(struct page *page, unsigned long vaddr)
 | 
						|
{
 | 
						|
	void *ptr, *kaddr = kmap_atomic(page);
 | 
						|
	asm volatile("\
 | 
						|
	mov	r1, %2				@ 1\n\
 | 
						|
	mov	r2, #0				@ 1\n\
 | 
						|
	mov	r3, #0				@ 1\n\
 | 
						|
	mov	ip, #0				@ 1\n\
 | 
						|
	mov	lr, #0				@ 1\n\
 | 
						|
1:	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
 | 
						|
	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
 | 
						|
	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
 | 
						|
	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
 | 
						|
	subs	r1, r1, #1			@ 1\n\
 | 
						|
	bne	1b				@ 1\n\
 | 
						|
	mcr	p15, 0, r2, c7, c7, 0		@ flush ID cache"
 | 
						|
	: "=r" (ptr)
 | 
						|
	: "0" (kaddr), "I" (PAGE_SIZE / 64)
 | 
						|
	: "r1", "r2", "r3", "ip", "lr");
 | 
						|
	kunmap_atomic(kaddr);
 | 
						|
}
 | 
						|
 | 
						|
struct cpu_user_fns v4wt_user_fns __initdata = {
 | 
						|
	.cpu_clear_user_highpage = v4wt_clear_user_highpage,
 | 
						|
	.cpu_copy_user_highpage	= v4wt_copy_user_highpage,
 | 
						|
};
 |