mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-12 13:34:10 +08:00
842ca547f7
page_mapping_file() is only used by some architectures, and then it is usually only used in one place. Make it a static inline function so other architectures don't have to carry this dead code. Link: https://lkml.kernel.org/r/20210317123011.350118-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
113 lines
3.2 KiB
C
113 lines
3.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* linux/arch/arm/lib/copypage-armv4mc.S
|
|
*
|
|
* Copyright (C) 1995-2005 Russell King
|
|
*
|
|
* This handles the mini data cache, as found on SA11x0 and XScale
|
|
* processors. When we copy a user page page, we map it in such a way
|
|
* that accesses to this page will not touch the main data cache, but
|
|
* will be cached in the mini data cache. This prevents us thrashing
|
|
* the main data cache on page faults.
|
|
*/
|
|
#include <linux/init.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/pagemap.h>
|
|
|
|
#include <asm/tlbflush.h>
|
|
#include <asm/cacheflush.h>
|
|
|
|
#include "mm.h"
|
|
|
|
#define minicache_pgprot __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | \
|
|
L_PTE_MT_MINICACHE)
|
|
|
|
static DEFINE_RAW_SPINLOCK(minicache_lock);
|
|
|
|
/*
|
|
* ARMv4 mini-dcache 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 mc_copy_user_page(void *from, void *to)
|
|
{
|
|
int tmp;
|
|
|
|
asm volatile ("\
|
|
.syntax unified\n\
|
|
ldmia %0!, {r2, r3, ip, lr} @ 4\n\
|
|
1: mcr p15, 0, %1, c7, c6, 1 @ 1 invalidate D line\n\
|
|
stmia %1!, {r2, r3, ip, lr} @ 4\n\
|
|
ldmia %0!, {r2, r3, ip, lr} @ 4+1\n\
|
|
stmia %1!, {r2, r3, ip, lr} @ 4\n\
|
|
ldmia %0!, {r2, r3, ip, lr} @ 4\n\
|
|
mcr p15, 0, %1, c7, c6, 1 @ 1 invalidate D line\n\
|
|
stmia %1!, {r2, r3, ip, lr} @ 4\n\
|
|
ldmia %0!, {r2, r3, ip, lr} @ 4\n\
|
|
subs %2, %2, #1 @ 1\n\
|
|
stmia %1!, {r2, r3, ip, lr} @ 4\n\
|
|
ldmiane %0!, {r2, r3, ip, lr} @ 4\n\
|
|
bne 1b @ "
|
|
: "+&r" (from), "+&r" (to), "=&r" (tmp)
|
|
: "2" (PAGE_SIZE / 64)
|
|
: "r2", "r3", "ip", "lr");
|
|
}
|
|
|
|
void v4_mc_copy_user_highpage(struct page *to, struct page *from,
|
|
unsigned long vaddr, struct vm_area_struct *vma)
|
|
{
|
|
void *kto = kmap_atomic(to);
|
|
|
|
if (!test_and_set_bit(PG_dcache_clean, &from->flags))
|
|
__flush_dcache_page(page_mapping_file(from), from);
|
|
|
|
raw_spin_lock(&minicache_lock);
|
|
|
|
set_top_pte(COPYPAGE_MINICACHE, mk_pte(from, minicache_pgprot));
|
|
|
|
mc_copy_user_page((void *)COPYPAGE_MINICACHE, kto);
|
|
|
|
raw_spin_unlock(&minicache_lock);
|
|
|
|
kunmap_atomic(kto);
|
|
}
|
|
|
|
/*
|
|
* ARMv4 optimised clear_user_page
|
|
*/
|
|
void v4_mc_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"
|
|
: "=r" (ptr)
|
|
: "0" (kaddr), "I" (PAGE_SIZE / 64)
|
|
: "r1", "r2", "r3", "ip", "lr");
|
|
kunmap_atomic(kaddr);
|
|
}
|
|
|
|
struct cpu_user_fns v4_mc_user_fns __initdata = {
|
|
.cpu_clear_user_highpage = v4_mc_clear_user_highpage,
|
|
.cpu_copy_user_highpage = v4_mc_copy_user_highpage,
|
|
};
|