From dd0f67f4747797f36f0c6bab7fed6a1f2448476d Mon Sep 17 00:00:00 2001 From: Joonsoo Kim Date: Fri, 5 Apr 2013 03:16:14 +0100 Subject: [PATCH] ARM: 7693/1: mm: clean-up in order to reduce to call kmap_high_get() In kmap_atomic(), kmap_high_get() is invoked for checking already mapped area. In __flush_dcache_page() and dma_cache_maint_page(), we explicitly call kmap_high_get() before kmap_atomic() when cache_is_vipt(), so kmap_high_get() can be invoked twice. This is useless operation, so remove one. v2: change cache_is_vipt() to cache_is_vipt_nonaliasing() in order to be self-documented Acked-by: Nicolas Pitre Signed-off-by: Joonsoo Kim Signed-off-by: Russell King --- arch/arm/mm/dma-mapping.c | 15 ++++++++------- arch/arm/mm/flush.c | 15 +++++++++------ 2 files changed, 17 insertions(+), 13 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index c7e3759f16d3..b47dd48d8634 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -822,16 +822,17 @@ static void dma_cache_maint_page(struct page *page, unsigned long offset, if (PageHighMem(page)) { if (len + offset > PAGE_SIZE) len = PAGE_SIZE - offset; - vaddr = kmap_high_get(page); - if (vaddr) { - vaddr += offset; - op(vaddr, len, dir); - kunmap_high(page); - } else if (cache_is_vipt()) { - /* unmapped pages might still be cached */ + + if (cache_is_vipt_nonaliasing()) { vaddr = kmap_atomic(page); op(vaddr + offset, len, dir); kunmap_atomic(vaddr); + } else { + vaddr = kmap_high_get(page); + if (vaddr) { + op(vaddr + offset, len, dir); + kunmap_high(page); + } } } else { vaddr = page_address(page) + offset; diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c index 1c8f7f564175..0d473cce501c 100644 --- a/arch/arm/mm/flush.c +++ b/arch/arm/mm/flush.c @@ -170,15 +170,18 @@ void __flush_dcache_page(struct address_space *mapping, struct page *page) if (!PageHighMem(page)) { __cpuc_flush_dcache_area(page_address(page), PAGE_SIZE); } else { - void *addr = kmap_high_get(page); - if (addr) { - __cpuc_flush_dcache_area(addr, PAGE_SIZE); - kunmap_high(page); - } else if (cache_is_vipt()) { - /* unmapped pages might still be cached */ + void *addr; + + if (cache_is_vipt_nonaliasing()) { addr = kmap_atomic(page); __cpuc_flush_dcache_area(addr, PAGE_SIZE); kunmap_atomic(addr); + } else { + addr = kmap_high_get(page); + if (addr) { + __cpuc_flush_dcache_area(addr, PAGE_SIZE); + kunmap_high(page); + } } }