linux/arch/microblaze/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

105 lines
3.6 KiB
C

/*
* Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2007-2009 PetaLogix
* Copyright (C) 2007 John Williams <john.williams@petalogix.com>
* based on v850 version which was
* Copyright (C) 2001,02,03 NEC Electronics Corporation
* Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
*
* 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.
*
*/
#ifndef _ASM_MICROBLAZE_CACHEFLUSH_H
#define _ASM_MICROBLAZE_CACHEFLUSH_H
/* Somebody depends on this; sigh... */
#include <linux/mm.h>
/*
* Cache handling functions.
* Microblaze has a write-through data cache, meaning that the data cache
* never needs to be flushed. The only flushing operations that are
* implemented are to invalidate the instruction cache. These are called
* after loading a user application into memory, we must invalidate the
* instruction cache to make sure we don't fetch old, bad code.
*/
/* FIXME for LL-temac driver */
#define invalidate_dcache_range(start, end) \
__invalidate_dcache_range(start, end)
#define flush_cache_all() __invalidate_cache_all()
#define flush_cache_mm(mm) do { } while (0)
#define flush_cache_range(vma, start, end) __invalidate_cache_all()
#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
#define flush_dcache_range(start, end) __invalidate_dcache_range(start, end)
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
#define flush_dcache_page(page) do { } while (0)
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
#define flush_icache_range(start, len) __invalidate_icache_range(start, len)
#define flush_icache_page(vma, pg) do { } while (0)
#ifndef CONFIG_MMU
# define flush_icache_user_range(start, len) do { } while (0)
#else
# define flush_icache_user_range(vma, pg, adr, len) __invalidate_icache_all()
# define flush_page_to_ram(page) do { } while (0)
# define flush_icache() __invalidate_icache_all()
# define flush_cache_sigtramp(vaddr) \
__invalidate_icache_range(vaddr, vaddr + 8)
# define flush_dcache_mmap_lock(mapping) do { } while (0)
# define flush_dcache_mmap_unlock(mapping) do { } while (0)
# define flush_cache_dup_mm(mm) do { } while (0)
#endif
#define flush_cache_vmap(start, end) do { } while (0)
#define flush_cache_vunmap(start, end) do { } while (0)
struct page;
struct mm_struct;
struct vm_area_struct;
/* see arch/microblaze/kernel/cache.c */
extern void __invalidate_icache_all(void);
extern void __invalidate_icache_range(unsigned long start, unsigned long end);
extern void __invalidate_icache_page(struct vm_area_struct *vma,
struct page *page);
extern void __invalidate_icache_user_range(struct vm_area_struct *vma,
struct page *page,
unsigned long adr, int len);
extern void __invalidate_cache_sigtramp(unsigned long addr);
extern void __invalidate_dcache_all(void);
extern void __invalidate_dcache_range(unsigned long start, unsigned long end);
extern void __invalidate_dcache_page(struct vm_area_struct *vma,
struct page *page);
extern void __invalidate_dcache_user_range(struct vm_area_struct *vma,
struct page *page,
unsigned long adr, int len);
extern inline void __invalidate_cache_all(void)
{
__invalidate_icache_all();
__invalidate_dcache_all();
}
#define copy_to_user_page(vma, page, vaddr, dst, src, len) \
do { memcpy((dst), (src), (len)); \
flush_icache_range((unsigned) (dst), (unsigned) (dst) + (len)); \
} while (0)
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
memcpy((dst), (src), (len))
#endif /* _ASM_MICROBLAZE_CACHEFLUSH_H */