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		f00a75c094
		
	
	
	
	
		
			
			Our copy_user_highpage() implementations may require cache maintainence. Ensure that implementations have all necessary details to perform this maintainence. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
		
			
				
	
	
		
			82 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  linux/arch/arm/mm/copypage-v3.c
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|  *
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|  *  Copyright (C) 1995-1999 Russell King
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| #include <linux/init.h>
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| #include <linux/highmem.h>
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| 
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| /*
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|  * ARMv3 optimised copy_user_highpage
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|  *
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|  * FIXME: do we need to handle cache stuff...
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|  */
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| static void __naked
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| v3_copy_user_page(void *kto, const void *kfrom)
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| {
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| 	asm("\n\
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| 	stmfd	sp!, {r4, lr}			@	2\n\
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| 	mov	r2, %2				@	1\n\
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| 	ldmia	%0!, {r3, r4, ip, lr}		@	4+1\n\
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| 1:	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
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| 	ldmia	%0!, {r3, r4, ip, lr}		@	4+1\n\
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| 	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
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| 	ldmia	%0!, {r3, r4, ip, lr}		@	4+1\n\
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| 	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
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| 	ldmia	%0!, {r3, r4, ip, lr}		@	4\n\
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| 	subs	r2, r2, #1			@	1\n\
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| 	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
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| 	ldmneia	%0!, {r3, r4, ip, lr}		@	4\n\
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| 	bne	1b				@	1\n\
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| 	ldmfd	sp!, {r4, pc}			@	3"
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| 	:
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| 	: "r" (kfrom), "r" (kto), "I" (PAGE_SIZE / 64));
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| }
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| 
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| void v3_copy_user_highpage(struct page *to, struct page *from,
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| 	unsigned long vaddr, struct vm_area_struct *vma)
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| {
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| 	void *kto, *kfrom;
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| 
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| 	kto = kmap_atomic(to, KM_USER0);
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| 	kfrom = kmap_atomic(from, KM_USER1);
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| 	v3_copy_user_page(kto, kfrom);
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| 	kunmap_atomic(kfrom, KM_USER1);
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| 	kunmap_atomic(kto, KM_USER0);
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| }
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| 
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| /*
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|  * ARMv3 optimised clear_user_page
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|  *
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|  * FIXME: do we need to handle cache stuff...
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|  */
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| void v3_clear_user_highpage(struct page *page, unsigned long vaddr)
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| {
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| 	void *ptr, *kaddr = kmap_atomic(page, KM_USER0);
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| 	asm volatile("\n\
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| 	mov	r1, %2				@ 1\n\
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| 	mov	r2, #0				@ 1\n\
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| 	mov	r3, #0				@ 1\n\
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| 	mov	ip, #0				@ 1\n\
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| 	mov	lr, #0				@ 1\n\
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| 1:	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
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| 	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
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| 	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
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| 	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
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| 	subs	r1, r1, #1			@ 1\n\
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| 	bne	1b				@ 1"
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| 	: "=r" (ptr)
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| 	: "0" (kaddr), "I" (PAGE_SIZE / 64)
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| 	: "r1", "r2", "r3", "ip", "lr");
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| 	kunmap_atomic(kaddr, KM_USER0);
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| }
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| 
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| struct cpu_user_fns v3_user_fns __initdata = {
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| 	.cpu_clear_user_highpage = v3_clear_user_highpage,
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| 	.cpu_copy_user_highpage	= v3_copy_user_highpage,
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| };
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