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 <nico@linaro.org>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 8 insertions, 7 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;