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>

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);
+                        }
                 }
         }