kernel-fxtec-pro1x/arch/mips/include/asm/cacheflush.h
Ilya Loginov 2d4dc890b5 block: add helpers to run flush_dcache_page() against a bio and a request's pages
Mtdblock driver doesn't call flush_dcache_page for pages in request.  So,
this causes problems on architectures where the icache doesn't fill from
the dcache or with dcache aliases.  The patch fixes this.

The ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE symbol was introduced to avoid
pointless empty cache-thrashing loops on architectures for which
flush_dcache_page() is a no-op.  Every architecture was provided with this
flush pages on architectires where ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE is
equal 1 or do nothing otherwise.

See "fix mtd_blkdevs problem with caches on some architectures" discussion
on LKML for more information.

Signed-off-by: Ilya Loginov <isloginov@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Peter Horton <phorton@bitbox.co.uk>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-11-26 09:16:19 +01:00

117 lines
3.9 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, 95, 96, 97, 98, 99, 2000, 01, 02, 03 by Ralf Baechle
* Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
*/
#ifndef _ASM_CACHEFLUSH_H
#define _ASM_CACHEFLUSH_H
/* Keep includes the same across arches. */
#include <linux/mm.h>
#include <asm/cpu-features.h>
/* Cache flushing:
*
* - flush_cache_all() flushes entire cache
* - flush_cache_mm(mm) flushes the specified mm context's cache lines
* - flush_cache_dup mm(mm) handles cache flushing when forking
* - flush_cache_page(mm, vmaddr, pfn) flushes a single page
* - flush_cache_range(vma, start, end) flushes a range of pages
* - flush_icache_range(start, end) flush a range of instructions
* - flush_dcache_page(pg) flushes(wback&invalidates) a page for dcache
*
* MIPS specific flush operations:
*
* - flush_cache_sigtramp() flush signal trampoline
* - flush_icache_all() flush the entire instruction cache
* - flush_data_cache_page() flushes a page from the data cache
*/
extern void (*flush_cache_all)(void);
extern void (*__flush_cache_all)(void);
extern void (*flush_cache_mm)(struct mm_struct *mm);
#define flush_cache_dup_mm(mm) do { (void) (mm); } while (0)
extern void (*flush_cache_range)(struct vm_area_struct *vma,
unsigned long start, unsigned long end);
extern void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page, unsigned long pfn);
extern void __flush_dcache_page(struct page *page);
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
static inline void flush_dcache_page(struct page *page)
{
if (cpu_has_dc_aliases || !cpu_has_ic_fills_f_dc)
__flush_dcache_page(page);
}
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
#define ARCH_HAS_FLUSH_ANON_PAGE
extern void __flush_anon_page(struct page *, unsigned long);
static inline void flush_anon_page(struct vm_area_struct *vma,
struct page *page, unsigned long vmaddr)
{
if (cpu_has_dc_aliases && PageAnon(page))
__flush_anon_page(page, vmaddr);
}
static inline void flush_icache_page(struct vm_area_struct *vma,
struct page *page)
{
}
extern void (*flush_icache_range)(unsigned long start, unsigned long end);
extern void (*local_flush_icache_range)(unsigned long start, unsigned long end);
extern void (*__flush_cache_vmap)(void);
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
if (cpu_has_dc_aliases)
__flush_cache_vmap();
}
extern void (*__flush_cache_vunmap)(void);
static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
{
if (cpu_has_dc_aliases)
__flush_cache_vunmap();
}
extern void copy_to_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr, void *dst, const void *src,
unsigned long len);
extern void copy_from_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr, void *dst, const void *src,
unsigned long len);
extern void (*flush_cache_sigtramp)(unsigned long addr);
extern void (*flush_icache_all)(void);
extern void (*local_flush_data_cache_page)(void * addr);
extern void (*flush_data_cache_page)(unsigned long addr);
/*
* This flag is used to indicate that the page pointed to by a pte
* is dirty and requires cleaning before returning it to the user.
*/
#define PG_dcache_dirty PG_arch_1
#define Page_dcache_dirty(page) \
test_bit(PG_dcache_dirty, &(page)->flags)
#define SetPageDcacheDirty(page) \
set_bit(PG_dcache_dirty, &(page)->flags)
#define ClearPageDcacheDirty(page) \
clear_bit(PG_dcache_dirty, &(page)->flags)
/* Run kernel code uncached, useful for cache probing functions. */
unsigned long run_uncached(void *func);
extern void *kmap_coherent(struct page *page, unsigned long addr);
extern void kunmap_coherent(void);
#endif /* _ASM_CACHEFLUSH_H */