kernel-ark/arch/mips/mm/cache.c
Atsushi Nemoto 750ccf687f Fix zero length sys_cacheflush
Cacheflush(0, 0, 0) was crashing the system.  This is because
flush_icache_range(start, end) tries to flushing whole address space
(0 - ~0UL) if both start and end are zero.
    
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:32:44 +01:00

154 lines
3.7 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 - 2003 by Ralf Baechle
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <asm/cacheflush.h>
#include <asm/processor.h>
#include <asm/cpu.h>
#include <asm/cpu-features.h>
/* Cache operations. */
void (*flush_cache_all)(void);
void (*__flush_cache_all)(void);
void (*flush_cache_mm)(struct mm_struct *mm);
void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
unsigned long end);
void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
unsigned long pfn);
void (*flush_icache_range)(unsigned long __user start,
unsigned long __user end);
void (*flush_icache_page)(struct vm_area_struct *vma, struct page *page);
/* MIPS specific cache operations */
void (*flush_cache_sigtramp)(unsigned long addr);
void (*flush_data_cache_page)(unsigned long addr);
void (*flush_icache_all)(void);
EXPORT_SYMBOL(flush_data_cache_page);
#ifdef CONFIG_DMA_NONCOHERENT
/* DMA cache operations. */
void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
void (*_dma_cache_wback)(unsigned long start, unsigned long size);
void (*_dma_cache_inv)(unsigned long start, unsigned long size);
EXPORT_SYMBOL(_dma_cache_wback_inv);
EXPORT_SYMBOL(_dma_cache_wback);
EXPORT_SYMBOL(_dma_cache_inv);
#endif /* CONFIG_DMA_NONCOHERENT */
/*
* We could optimize the case where the cache argument is not BCACHE but
* that seems very atypical use ...
*/
asmlinkage int sys_cacheflush(unsigned long __user addr,
unsigned long bytes, unsigned int cache)
{
if (bytes == 0)
return 0;
if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
return -EFAULT;
flush_icache_range(addr, addr + bytes);
return 0;
}
void __flush_dcache_page(struct page *page)
{
struct address_space *mapping = page_mapping(page);
unsigned long addr;
if (mapping && !mapping_mapped(mapping)) {
SetPageDcacheDirty(page);
return;
}
/*
* We could delay the flush for the !page_mapping case too. But that
* case is for exec env/arg pages and those are %99 certainly going to
* get faulted into the tlb (and thus flushed) anyways.
*/
addr = (unsigned long) page_address(page);
flush_data_cache_page(addr);
}
EXPORT_SYMBOL(__flush_dcache_page);
void __update_cache(struct vm_area_struct *vma, unsigned long address,
pte_t pte)
{
struct page *page;
unsigned long pfn, addr;
pfn = pte_pfn(pte);
if (pfn_valid(pfn) && (page = pfn_to_page(pfn), page_mapping(page)) &&
Page_dcache_dirty(page)) {
if (pages_do_alias((unsigned long)page_address(page),
address & PAGE_MASK)) {
addr = (unsigned long) page_address(page);
flush_data_cache_page(addr);
}
ClearPageDcacheDirty(page);
}
}
#define __weak __attribute__((weak))
static char cache_panic[] __initdata = "Yeee, unsupported cache architecture.";
void __init cpu_cache_init(void)
{
if (cpu_has_3k_cache) {
extern void __weak r3k_cache_init(void);
r3k_cache_init();
return;
}
if (cpu_has_6k_cache) {
extern void __weak r6k_cache_init(void);
r6k_cache_init();
return;
}
if (cpu_has_4k_cache) {
extern void __weak r4k_cache_init(void);
r4k_cache_init();
return;
}
if (cpu_has_8k_cache) {
extern void __weak r8k_cache_init(void);
r8k_cache_init();
return;
}
if (cpu_has_tx39_cache) {
extern void __weak tx39_cache_init(void);
tx39_cache_init();
return;
}
if (cpu_has_sb1_cache) {
extern void __weak sb1_cache_init(void);
sb1_cache_init();
return;
}
panic(cache_panic);
}