From c01778001a4f5ad9c62d882776235f3f31922fdd Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 13 Sep 2010 15:57:36 +0100 Subject: ARM: 6379/1: Assume new page cache pages have dirty D-cache There are places in Linux where writes to newly allocated page cache pages happen without a subsequent call to flush_dcache_page() (several PIO drivers including USB HCD). This patch changes the meaning of PG_arch_1 to be PG_dcache_clean and always flush the D-cache for a newly mapped page in update_mmu_cache(). The patch also sets the PG_arch_1 bit in the DMA cache maintenance function to avoid additional cache flushing in update_mmu_cache(). Tested-by: Rabin Vincent Cc: Nicolas Pitre Signed-off-by: Catalin Marinas Signed-off-by: Russell King --- arch/arm/mm/fault-armv.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm/mm/fault-armv.c') diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c index 9b906dec1ca1..58846cbd0e0b 100644 --- a/arch/arm/mm/fault-armv.c +++ b/arch/arm/mm/fault-armv.c @@ -141,7 +141,7 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma, * a page table, or changing an existing PTE. Basically, there are two * things that we need to take care of: * - * 1. If PG_dcache_dirty is set for the page, we need to ensure + * 1. If PG_dcache_clean is not set for the page, we need to ensure * that any cache entries for the kernels virtual memory * range are written back to the page. * 2. If we have multiple shared mappings of the same space in @@ -169,7 +169,7 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, mapping = page_mapping(page); #ifndef CONFIG_SMP - if (test_and_clear_bit(PG_dcache_dirty, &page->flags)) + if (!test_and_set_bit(PG_dcache_clean, &page->flags)) __flush_dcache_page(mapping, page); #endif if (mapping) { -- cgit