From 92dc6fcc845d99e87d8168e0786796525832d130 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sat, 29 Oct 2005 18:16:36 -0700 Subject: [PATCH] mm: parisc pte atomicity There's a worrying function translation_exists in parisc cacheflush.h, unaffected by split ptlock since flush_dcache_page is using it on some other mm, without any relevant lock. Oh well, make it a slightly more robust by factoring the pfn check within it. And it looked liable to confuse a camouflaged swap or file entry with a good pte: fix that too. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/parisc/kernel/cache.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-) (limited to 'arch/parisc/kernel/cache.c') diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c index e15f09eaed12..a065349aee37 100644 --- a/arch/parisc/kernel/cache.c +++ b/arch/parisc/kernel/cache.c @@ -270,7 +270,6 @@ void flush_dcache_page(struct page *page) unsigned long offset; unsigned long addr; pgoff_t pgoff; - pte_t *pte; unsigned long pfn = page_to_pfn(page); @@ -301,21 +300,16 @@ void flush_dcache_page(struct page *page) * taking a page fault if the pte doesn't exist. * This is just for speed. If the page translation * isn't there, there's no point exciting the - * nadtlb handler into a nullification frenzy */ - - - if(!(pte = translation_exists(mpnt, addr))) - continue; - - /* make sure we really have this page: the private + * nadtlb handler into a nullification frenzy. + * + * Make sure we really have this page: the private * mappings may cover this area but have COW'd this - * particular page */ - if(pte_pfn(*pte) != pfn) - continue; - - __flush_cache_page(mpnt, addr); - - break; + * particular page. + */ + if (translation_exists(mpnt, addr, pfn)) { + __flush_cache_page(mpnt, addr); + break; + } } flush_dcache_mmap_unlock(mapping); } -- cgit v1.2.3