tegrakernel/kernel/kernel-4.9/arch/unicore32/mm/flush.c

98 lines
2.4 KiB
C

/*
* linux/arch/unicore32/mm/flush.c
*
* Code specific to PKUnity SoC and UniCore ISA
*
* Copyright (C) 2001-2010 GUAN Xue-tao
*
* 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/module.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
void flush_cache_mm(struct mm_struct *mm)
{
}
void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
if (vma->vm_flags & VM_EXEC)
__flush_icache_all();
}
void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr,
unsigned long pfn)
{
}
static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
unsigned long uaddr, void *kaddr, unsigned long len)
{
/* VIPT non-aliasing D-cache */
if (vma->vm_flags & VM_EXEC) {
unsigned long addr = (unsigned long)kaddr;
__cpuc_coherent_kern_range(addr, addr + len);
}
}
/*
* Copy user data from/to a page which is mapped into a different
* processes address space. Really, we want to allow our "user
* space" model to handle this.
*
* Note that this code needs to run on the current CPU.
*/
void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long uaddr, void *dst, const void *src,
unsigned long len)
{
memcpy(dst, src, len);
flush_ptrace_access(vma, page, uaddr, dst, len);
}
void __flush_dcache_page(struct address_space *mapping, struct page *page)
{
/*
* Writeback any data associated with the kernel mapping of this
* page. This ensures that data in the physical page is mutually
* coherent with the kernels mapping.
*/
__cpuc_flush_kern_dcache_area(page_address(page), PAGE_SIZE);
}
/*
* Ensure cache coherency between kernel mapping and userspace mapping
* of this page.
*/
void flush_dcache_page(struct page *page)
{
struct address_space *mapping;
/*
* The zero page is never written to, so never has any dirty
* cache lines, and therefore never needs to be flushed.
*/
if (page == ZERO_PAGE(0))
return;
mapping = page_mapping(page);
if (mapping && !mapping_mapped(mapping))
clear_bit(PG_dcache_clean, &page->flags);
else {
__flush_dcache_page(mapping, page);
if (mapping)
__flush_icache_all();
set_bit(PG_dcache_clean, &page->flags);
}
}
EXPORT_SYMBOL(flush_dcache_page);