linux/include/asm-sh/cpu-sh4/cacheflush.h
Paul Mundt 8b395265f8 sh: Fix fatal oops in copy_user_page() on sh4a (SH7780).
We had a pretty interesting oops happening, where copy_user_page()
was down()'ing p3map_sem[] with a bogus offset (particularly, an
offset that hadn't been initialized with sema_init(), due to the
mismatch between cpu_data->dcache.n_aliases and what was assumed
based off of the old CACHE_ALIAS value).

Luckily, spinlock debugging caught this for us, and so we drop
the old hardcoded CACHE_ALIAS for sh4 completely and rely on the
run-time probed cpu_data->dcache.alias_mask. This in turn gets
the p3map_sem[] index right, and everything works again.

While we're at it, also convert to 4-level page tables..

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-09-27 14:38:02 +09:00

61 lines
1.9 KiB
C

/*
* include/asm-sh/cpu-sh4/cacheflush.h
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2003 Paul Mundt
*
* 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_CPU_SH4_CACHEFLUSH_H
#define __ASM_CPU_SH4_CACHEFLUSH_H
/*
* Caches are broken on SH-4 (unless we use write-through
* caching; in which case they're only semi-broken),
* so we need them.
*/
struct page;
struct mm_struct;
struct vm_area_struct;
extern void flush_cache_all(void);
extern void flush_cache_mm(struct mm_struct *mm);
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 addr, unsigned long pfn);
extern void flush_dcache_page(struct page *pg);
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
extern void flush_icache_range(unsigned long start, unsigned long end);
extern void flush_cache_sigtramp(unsigned long addr);
extern void flush_icache_user_range(struct vm_area_struct *vma,
struct page *page, unsigned long addr,
int len);
#define flush_icache_page(vma,pg) do { } while (0)
/* Initialization of P3 area for copy_user_page */
extern void p3_cache_init(void);
#define PG_mapped PG_arch_1
/* We provide our own get_unmapped_area to avoid cache alias issue */
#define HAVE_ARCH_UNMAPPED_AREA
#ifdef CONFIG_MMU
extern int remap_area_pages(unsigned long addr, unsigned long phys_addr,
unsigned long size, unsigned long flags);
#else /* CONFIG_MMU */
static inline int remap_area_pages(unsigned long addr, unsigned long phys_addr,
unsigned long size, unsigned long flags)
{
return 0;
}
#endif /* CONFIG_MMU */
#endif /* __ASM_CPU_SH4_CACHEFLUSH_H */