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Release 4.11 arch/arm/mm/copypage-v4wb.c

Directory: arch/arm/mm
/*
 *  linux/arch/arm/mm/copypage-v4wb.c
 *
 *  Copyright (C) 1995-1999 Russell King
 *
 * 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.
 */
#include <linux/init.h>
#include <linux/highmem.h>

/*
 * ARMv4 optimised copy_user_highpage
 *
 * We flush the destination cache lines just before we write the data into the
 * corresponding address.  Since the Dcache is read-allocate, this removes the
 * Dcache aliasing issue.  The writes will be forwarded to the write buffer,
 * and merged as appropriate.
 *
 * Note: We rely on all ARMv4 processors implementing the "invalidate D line"
 * instruction.  If your processor does not supply this, you have to write your
 * own copy_user_highpage that does the right thing.
 */

static void __naked v4wb_copy_user_page(void *kto, const void *kfrom) { asm("\ stmfd sp!, {r4, lr} @ 2\n\ mov r2, %2 @ 1\n\ ldmia r1!, {r3, r4, ip, lr} @ 4\n\ 1: mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line\n\ stmia r0!, {r3, r4, ip, lr} @ 4\n\ ldmia r1!, {r3, r4, ip, lr} @ 4+1\n\ stmia r0!, {r3, r4, ip, lr} @ 4\n\ ldmia r1!, {r3, r4, ip, lr} @ 4\n\ mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line\n\ stmia r0!, {r3, r4, ip, lr} @ 4\n\ ldmia r1!, {r3, r4, ip, lr} @ 4\n\ subs r2, r2, #1 @ 1\n\ stmia r0!, {r3, r4, ip, lr} @ 4\n\ ldmneia r1!, {r3, r4, ip, lr} @ 4\n\ bne 1b @ 1\n\ mcr p15, 0, r1, c7, c10, 4 @ 1 drain WB\n\ ldmfd sp!, {r4, pc} @ 3" : : "r" (kto), "r" (kfrom), "I" (PAGE_SIZE / 64)); }

Contributors

PersonTokensPropCommitsCommitProp
Russell King1058.82%250.00%
Uwe Kleine-König635.29%125.00%
Khem Raj15.88%125.00%
Total17100.00%4100.00%


void v4wb_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); flush_cache_page(vma, vaddr, page_to_pfn(from)); v4wb_copy_user_page(kto, kfrom); kunmap_atomic(kfrom); kunmap_atomic(kto); }

Contributors

PersonTokensPropCommitsCommitProp
Russell King74100.00%3100.00%
Total74100.00%3100.00%

/* * ARMv4 optimised clear_user_page * * Same story as above. */
void v4wb_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: mcr p15, 0, %0, c7, c6, 1 @ 1 invalidate D line\n\ stmia %0!, {r2, r3, ip, lr} @ 4\n\ stmia %0!, {r2, r3, ip, lr} @ 4\n\ mcr p15, 0, %0, c7, c6, 1 @ 1 invalidate D line\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, r1, c7, c10, 4 @ 1 drain WB" : "=r" (ptr) : "0" (kaddr), "I" (PAGE_SIZE / 64) : "r1", "r2", "r3", "ip", "lr"); kunmap_atomic(kaddr); }

Contributors

PersonTokensPropCommitsCommitProp
Russell King2882.35%266.67%
Nico Pitre617.65%133.33%
Total34100.00%3100.00%

struct cpu_user_fns v4wb_user_fns __initdata = { .cpu_clear_user_highpage = v4wb_clear_user_highpage, .cpu_copy_user_highpage = v4wb_copy_user_highpage, };

Overall Contributors

PersonTokensPropCommitsCommitProp
Russell King13891.39%562.50%
Nico Pitre63.97%112.50%
Uwe Kleine-König63.97%112.50%
Khem Raj10.66%112.50%
Total151100.00%8100.00%
Directory: arch/arm/mm
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