mirror of
				https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
				synced 2025-10-31 16:23:20 +00:00 
			
		
		
		
	 9a40ac8615
			
		
	
	
		9a40ac8615
		
	
	
	
	
		
			
			When functions incoming parameters are not in input operands list gcc 4.5 does not load the parameters into registers before calling this function but the inline assembly assumes valid addresses inside this function. This breaks the code because r0 and r1 are invalid when execution enters v4wb_copy_user_page () Also the constant needs to be used as third input operand so account for that as well. Tested on qemu arm. CC: <stable@kernel.org> Signed-off-by: Khem Raj <raj.khem@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
		
			
				
	
	
		
			115 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			115 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  *  linux/arch/arm/mm/copypage-xsc3.S
 | |
|  *
 | |
|  *  Copyright (C) 2004 Intel Corp.
 | |
|  *
 | |
|  * 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.
 | |
|  *
 | |
|  * Adapted for 3rd gen XScale core, no more mini-dcache
 | |
|  * Author: Matt Gilbert (matthew.m.gilbert@intel.com)
 | |
|  */
 | |
| #include <linux/init.h>
 | |
| #include <linux/highmem.h>
 | |
| 
 | |
| /*
 | |
|  * General note:
 | |
|  *  We don't really want write-allocate cache behaviour for these functions
 | |
|  *  since that will just eat through 8K of the cache.
 | |
|  */
 | |
| 
 | |
| /*
 | |
|  * XSC3 optimised copy_user_highpage
 | |
|  *  r0 = destination
 | |
|  *  r1 = source
 | |
|  *
 | |
|  * The source page may have some clean entries in the cache already, but we
 | |
|  * can safely ignore them - break_cow() will flush them out of the cache
 | |
|  * if we eventually end up using our copied page.
 | |
|  *
 | |
|  */
 | |
| static void __naked
 | |
| xsc3_mc_copy_user_page(void *kto, const void *kfrom)
 | |
| {
 | |
| 	asm("\
 | |
| 	stmfd	sp!, {r4, r5, lr}		\n\
 | |
| 	mov	lr, %2				\n\
 | |
| 						\n\
 | |
| 	pld	[r1, #0]			\n\
 | |
| 	pld	[r1, #32]			\n\
 | |
| 1:	pld	[r1, #64]			\n\
 | |
| 	pld	[r1, #96]			\n\
 | |
| 						\n\
 | |
| 2:	ldrd	r2, [r1], #8			\n\
 | |
| 	mov	ip, r0				\n\
 | |
| 	ldrd	r4, [r1], #8			\n\
 | |
| 	mcr	p15, 0, ip, c7, c6, 1		@ invalidate\n\
 | |
| 	strd	r2, [r0], #8			\n\
 | |
| 	ldrd	r2, [r1], #8			\n\
 | |
| 	strd	r4, [r0], #8			\n\
 | |
| 	ldrd	r4, [r1], #8			\n\
 | |
| 	strd	r2, [r0], #8			\n\
 | |
| 	strd	r4, [r0], #8			\n\
 | |
| 	ldrd	r2, [r1], #8			\n\
 | |
| 	mov	ip, r0				\n\
 | |
| 	ldrd	r4, [r1], #8			\n\
 | |
| 	mcr	p15, 0, ip, c7, c6, 1		@ invalidate\n\
 | |
| 	strd	r2, [r0], #8			\n\
 | |
| 	ldrd	r2, [r1], #8			\n\
 | |
| 	subs	lr, lr, #1			\n\
 | |
| 	strd	r4, [r0], #8			\n\
 | |
| 	ldrd	r4, [r1], #8			\n\
 | |
| 	strd	r2, [r0], #8			\n\
 | |
| 	strd	r4, [r0], #8			\n\
 | |
| 	bgt	1b				\n\
 | |
| 	beq	2b				\n\
 | |
| 						\n\
 | |
| 	ldmfd	sp!, {r4, r5, pc}"
 | |
| 	:
 | |
| 	: "r" (kto), "r" (kfrom), "I" (PAGE_SIZE / 64 - 1));
 | |
| }
 | |
| 
 | |
| void xsc3_mc_copy_user_highpage(struct page *to, struct page *from,
 | |
| 	unsigned long vaddr, struct vm_area_struct *vma)
 | |
| {
 | |
| 	void *kto, *kfrom;
 | |
| 
 | |
| 	kto = kmap_atomic(to, KM_USER0);
 | |
| 	kfrom = kmap_atomic(from, KM_USER1);
 | |
| 	flush_cache_page(vma, vaddr, page_to_pfn(from));
 | |
| 	xsc3_mc_copy_user_page(kto, kfrom);
 | |
| 	kunmap_atomic(kfrom, KM_USER1);
 | |
| 	kunmap_atomic(kto, KM_USER0);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * XScale optimised clear_user_page
 | |
|  *  r0 = destination
 | |
|  *  r1 = virtual user address of ultimate destination page
 | |
|  */
 | |
| void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
 | |
| {
 | |
| 	void *ptr, *kaddr = kmap_atomic(page, KM_USER0);
 | |
| 	asm volatile ("\
 | |
| 	mov	r1, %2				\n\
 | |
| 	mov	r2, #0				\n\
 | |
| 	mov	r3, #0				\n\
 | |
| 1:	mcr	p15, 0, %0, c7, c6, 1		@ invalidate line\n\
 | |
| 	strd	r2, [%0], #8			\n\
 | |
| 	strd	r2, [%0], #8			\n\
 | |
| 	strd	r2, [%0], #8			\n\
 | |
| 	strd	r2, [%0], #8			\n\
 | |
| 	subs	r1, r1, #1			\n\
 | |
| 	bne	1b"
 | |
| 	: "=r" (ptr)
 | |
| 	: "0" (kaddr), "I" (PAGE_SIZE / 32)
 | |
| 	: "r1", "r2", "r3");
 | |
| 	kunmap_atomic(kaddr, KM_USER0);
 | |
| }
 | |
| 
 | |
| struct cpu_user_fns xsc3_mc_user_fns __initdata = {
 | |
| 	.cpu_clear_user_highpage = xsc3_mc_clear_user_highpage,
 | |
| 	.cpu_copy_user_highpage	= xsc3_mc_copy_user_highpage,
 | |
| };
 |