kernel-ark/arch/arm/mm/copypage-feroceon.c
Russell King 063b0a4207 [ARM] copypage: provide our own copy_user_highpage()
We used to override the copy_user_page() function.  However, this
is not only inefficient, it also causes additional complexity for
highmem support, since we convert from a struct page to a kernel
direct mapped address and back to a struct page again.

Moreover, with highmem support, we end up pointlessly setting up
kmap entries for pages which we're going to remap.  So, push the
kmapping down into the copypage implementation files where it's
required.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-11-27 23:53:47 +00:00

112 lines
3.0 KiB
C

/*
* linux/arch/arm/mm/copypage-feroceon.S
*
* Copyright (C) 2008 Marvell Semiconductors
*
* 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 handles copy_user_highpage and clear_user_page on Feroceon
* more optimally than the generic implementations.
*/
#include <linux/init.h>
#include <linux/highmem.h>
static void __attribute__((naked))
feroceon_copy_user_page(void *kto, const void *kfrom)
{
asm("\
stmfd sp!, {r4-r9, lr} \n\
mov ip, %0 \n\
1: mov lr, r1 \n\
ldmia r1!, {r2 - r9} \n\
pld [lr, #32] \n\
pld [lr, #64] \n\
pld [lr, #96] \n\
pld [lr, #128] \n\
pld [lr, #160] \n\
pld [lr, #192] \n\
pld [lr, #224] \n\
stmia r0, {r2 - r9} \n\
ldmia r1!, {r2 - r9} \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
stmia r0, {r2 - r9} \n\
ldmia r1!, {r2 - r9} \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
stmia r0, {r2 - r9} \n\
ldmia r1!, {r2 - r9} \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
stmia r0, {r2 - r9} \n\
ldmia r1!, {r2 - r9} \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
stmia r0, {r2 - r9} \n\
ldmia r1!, {r2 - r9} \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
stmia r0, {r2 - r9} \n\
ldmia r1!, {r2 - r9} \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
stmia r0, {r2 - r9} \n\
ldmia r1!, {r2 - r9} \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
stmia r0, {r2 - r9} \n\
subs ip, ip, #(32 * 8) \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
bne 1b \n\
mcr p15, 0, ip, c7, c10, 4 @ drain WB\n\
ldmfd sp!, {r4-r9, pc}"
:
: "I" (PAGE_SIZE));
}
void feroceon_copy_user_highpage(struct page *to, struct page *from,
unsigned long vaddr)
{
void *kto, *kfrom;
kto = kmap_atomic(to, KM_USER0);
kfrom = kmap_atomic(from, KM_USER1);
feroceon_copy_user_page(kto, kfrom);
kunmap_atomic(kfrom, KM_USER1);
kunmap_atomic(kto, KM_USER0);
}
void __attribute__((naked))
feroceon_clear_user_page(void *kaddr, unsigned long vaddr)
{
asm("\
stmfd sp!, {r4-r7, lr} \n\
mov r1, %0 \n\
mov r2, #0 \n\
mov r3, #0 \n\
mov r4, #0 \n\
mov r5, #0 \n\
mov r6, #0 \n\
mov r7, #0 \n\
mov ip, #0 \n\
mov lr, #0 \n\
1: stmia r0, {r2-r7, ip, lr} \n\
subs r1, r1, #1 \n\
mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
add r0, r0, #32 \n\
bne 1b \n\
mcr p15, 0, r1, c7, c10, 4 @ drain WB\n\
ldmfd sp!, {r4-r7, pc}"
:
: "I" (PAGE_SIZE / 32));
}
struct cpu_user_fns feroceon_user_fns __initdata = {
.cpu_clear_user_page = feroceon_clear_user_page,
.cpu_copy_user_highpage = feroceon_copy_user_highpage,
};