arm64 may need to guarantee the caches are synced. Implement versions of
the kernel_force_cache API based on the DMA APIs.
Signed-off-by: Laura Abbott <labbott@xxxxxxxxxx>
---
arch/arm64/include/asm/cacheflush.h | 5 +++++
arch/arm64/mm/flush.c | 11 +++++++++++
2 files changed, 16 insertions(+)
diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h
index c64268d..9980dd8 100644
--- a/arch/arm64/include/asm/cacheflush.h
+++ b/arch/arm64/include/asm/cacheflush.h
@@ -149,4 +149,9 @@ int set_memory_rw(unsigned long addr, int numpages);
int set_memory_x(unsigned long addr, int numpages);
int set_memory_nx(unsigned long addr, int numpages);
+#define ARCH_HAS_FORCE_CACHE 1
+
+void kernel_force_cache_clean(struct page *page, size_t size);
+void kernel_force_cache_invalidate(struct page *page, size_t size);
+
#endif
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index 43a76b0..0af78ab 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -20,6 +20,7 @@
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
+#include <linux/dma-mapping.h>
#include <asm/cacheflush.h>
#include <asm/cachetype.h>
@@ -94,3 +95,13 @@ EXPORT_SYMBOL(flush_dcache_page);
* Additional functions defined in assembly.
*/
EXPORT_SYMBOL(flush_icache_range);
+
+void kernel_force_cache_clean(struct page *page, size_t size)
+{
+ __dma_map_area(page_address(page), size, DMA_BIDIRECTIONAL);
+}
+
+void kernel_force_cache_invalidate(struct page *page, size_t size)
+{
+ __dma_unmap_area(page_address(page), size, DMA_BIDIRECTIONAL);
+}
--
2.7.4
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