[RFC PATCH 2/6] ARM: mm: Add support for flushing HugeTLB pages.
Steve Capper
steve.capper at arm.com
Thu Oct 18 12:15:38 EDT 2012
On ARM we use the __flush_dcache_page function to flush the dcache of pages
when needed; usually when the PG_dcache_clean bit is unset and we are setting a
PTE.
A HugeTLB page is represented as a compound page consisting of an array of
pages. Thus to flush the dcache of a HugeTLB page, one must flush more than a
single page.
This patch modifies __flush_dcache_page such that all constituent pages of a
HugeTLB page are flushed.
Signed-off-by: Will Deacon <will.deacon at arm.com>
Signed-off-by: Steve Capper <steve.capper at arm.com>
---
arch/arm/mm/flush.c | 25 +++++++++++++++----------
1 file changed, 15 insertions(+), 10 deletions(-)
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 1c8f7f5..0a69cb8 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -17,6 +17,7 @@
#include <asm/highmem.h>
#include <asm/smp_plat.h>
#include <asm/tlbflush.h>
+#include <linux/hugetlb.h>
#include "mm.h"
@@ -168,17 +169,21 @@ void __flush_dcache_page(struct address_space *mapping, struct page *page)
* coherent with the kernels mapping.
*/
if (!PageHighMem(page)) {
- __cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
+ __cpuc_flush_dcache_area(page_address(page), (PAGE_SIZE << compound_order(page)));
} 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 */
- addr = kmap_atomic(page);
- __cpuc_flush_dcache_area(addr, PAGE_SIZE);
- kunmap_atomic(addr);
+ unsigned long i;
+ for(i = 0; i < (1 << compound_order(page)); i++) {
+ struct page *cpage = page + i;
+ void *addr = kmap_high_get(cpage);
+ if (addr) {
+ __cpuc_flush_dcache_area(addr, PAGE_SIZE);
+ kunmap_high(cpage);
+ } else if (cache_is_vipt()) {
+ /* unmapped pages might still be cached */
+ addr = kmap_atomic(cpage);
+ __cpuc_flush_dcache_area(addr, PAGE_SIZE);
+ kunmap_atomic(addr);
+ }
}
}
--
1.7.9.5
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