alistair23-linux/arch/arm/mm/copypage-xsc3.c
Khem Raj 9a40ac8615 ARM: 6164/1: Add kto and kfrom to input operands list.
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>
2010-06-08 19:42:18 +01:00

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,
};