From bcd022801ee514e28c32837f0b3ce18c775f1a7b Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Tue, 12 Dec 2006 17:14:56 +0000 Subject: [PATCH] MIPS: Fix COW D-cache aliasing on fork Provide a custom copy_user_highpage() to deal with aliasing issues on MIPS. It uses kmap_coherent() to map an user page for kernel with same color. Rewrite copy_to_user_page() and copy_from_user_page() with the new interfaces to avoid extra cache flushing. The main part of this patch was originally written by Ralf Baechle; Atushi Nemoto did the the debugging. Signed-off-by: Atsushi Nemoto Signed-off-by: Ralf Baechle Signed-off-by: Linus Torvalds --- include/asm-mips/page.h | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) (limited to 'include') diff --git a/include/asm-mips/page.h b/include/asm-mips/page.h index 0dc1a45c27e..2f9e1a9ec51 100644 --- a/include/asm-mips/page.h +++ b/include/asm-mips/page.h @@ -35,7 +35,6 @@ #ifndef __ASSEMBLY__ #include -#include #include extern void clear_page(void * page); @@ -61,16 +60,13 @@ static inline void clear_user_page(void *addr, unsigned long vaddr, flush_data_cache_page((unsigned long)addr); } -static inline void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, - struct page *to) -{ - extern void (*flush_data_cache_page)(unsigned long addr); +extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, + struct page *to); +struct vm_area_struct; +extern void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma); - copy_page(vto, vfrom); - if (!cpu_has_ic_fills_f_dc || - pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) - flush_data_cache_page((unsigned long)vto); -} +#define __HAVE_ARCH_COPY_USER_HIGHPAGE /* * These are used to make use of C type-checking.. -- cgit v1.2.3