LXR linux/arch/arm/mm/copypage-v3.c

   1/*
   2 *  linux/arch/arm/mm/copypage-v3.c
   3 *
   4 *  Copyright (C) 1995-1999 Russell King
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 */
  10#include <linux/init.h>
  11#include <linux/highmem.h>
  12
  13/*
  14 * ARMv3 optimised copy_user_highpage
  15 *
  16 * FIXME: do we need to handle cache stuff...
  17 */
  18static void __naked
  19v3_copy_user_page(void *kto, const void *kfrom)
  20{
  21        asm("\n\
  22        stmfd   sp!, {r4, lr}                   @       2\n\
  23        mov     r2, %2                          @       1\n\
  24        ldmia   %0!, {r3, r4, ip, lr}           @       4+1\n\
  251:      stmia   %1!, {r3, r4, ip, lr}           @       4\n\
  26        ldmia   %0!, {r3, r4, ip, lr}           @       4+1\n\
  27        stmia   %1!, {r3, r4, ip, lr}           @       4\n\
  28        ldmia   %0!, {r3, r4, ip, lr}           @       4+1\n\
  29        stmia   %1!, {r3, r4, ip, lr}           @       4\n\
  30        ldmia   %0!, {r3, r4, ip, lr}           @       4\n\
  31        subs    r2, r2, #1                      @       1\n\
  32        stmia   %1!, {r3, r4, ip, lr}           @       4\n\
  33        ldmneia %0!, {r3, r4, ip, lr}           @       4\n\
  34        bne     1b                              @       1\n\
  35        ldmfd   sp!, {r4, pc}                   @       3"
  36        :
  37        : "r" (kfrom), "r" (kto), "I" (PAGE_SIZE / 64));
  38}
  39
  40void v3_copy_user_highpage(struct page *to, struct page *from,
  41        unsigned long vaddr, struct vm_area_struct *vma)
  42{
  43        void *kto, *kfrom;
  44
  45        kto = kmap_atomic(to, KM_USER0);
  46        kfrom = kmap_atomic(from, KM_USER1);
  47        v3_copy_user_page(kto, kfrom);
  48        kunmap_atomic(kfrom, KM_USER1);
  49        kunmap_atomic(kto, KM_USER0);
  50}
  51
  52/*
  53 * ARMv3 optimised clear_user_page
  54 *
  55 * FIXME: do we need to handle cache stuff...
  56 */
  57void v3_clear_user_highpage(struct page *page, unsigned long vaddr)
  58{
  59        void *ptr, *kaddr = kmap_atomic(page, KM_USER0);
  60        asm volatile("\n\
  61        mov     r1, %2                          @ 1\n\
  62        mov     r2, #0                          @ 1\n\
  63        mov     r3, #0                          @ 1\n\
  64        mov     ip, #0                          @ 1\n\
  65        mov     lr, #0                          @ 1\n\
  661:      stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
  67        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
  68        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
  69        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
  70        subs    r1, r1, #1                      @ 1\n\
  71        bne     1b                              @ 1"
  72        : "=r" (ptr)
  73        : "0" (kaddr), "I" (PAGE_SIZE / 64)
  74        : "r1", "r2", "r3", "ip", "lr");
  75        kunmap_atomic(kaddr, KM_USER0);
  76}
  77
  78struct cpu_user_fns v3_user_fns __initdata = {
  79        .cpu_clear_user_highpage = v3_clear_user_highpage,
  80        .cpu_copy_user_highpage = v3_copy_user_highpage,
  81};
  82