Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

[sfrench/cifs-2.6.git] / arch / arm64 / include / asm / pgtable.h

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 576128635f3ca2927461c0aed33d39dba703b93a..de70c1eabf336abc2473dddb4e788d15599bc58b 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -22,6 +22,7 @@
 #include <asm/memory.h>
 #include <asm/pgtable-hwdef.h>
 #include <asm/pgtable-prot.h>
+#include <asm/tlbflush.h>
 
 /*
  * VMALLOC range.
@@ -694,6 +695,27 @@ static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
        return __ptep_test_and_clear_young(ptep);
 }
 
+#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
+static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
+                                        unsigned long address, pte_t *ptep)
+{
+       int young = ptep_test_and_clear_young(vma, address, ptep);
+
+       if (young) {
+               /*
+                * We can elide the trailing DSB here since the worst that can
+                * happen is that a CPU continues to use the young entry in its
+                * TLB and we mistakenly reclaim the associated page. The
+                * window for such an event is bounded by the next
+                * context-switch, which provides a DSB to complete the TLB
+                * invalidation.
+                */
+               flush_tlb_page_nosync(vma, address);
+       }
+
+       return young;
+}
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,