summaryrefslogtreecommitdiff
path: root/include/linux/mmu_notifier.h
diff options
context:
space:
mode:
authorAndres Lagar-Cavilla <andreslc@google.com>2014-09-23 01:54:42 +0400
committerPaolo Bonzini <pbonzini@redhat.com>2014-09-24 16:07:58 +0400
commit57128468080a8b6ea452223036d3e417f748af55 (patch)
treee89cfc349a9c39710cfab4e387119365a0d64958 /include/linux/mmu_notifier.h
parent8a9522d2fe6a1b643d3aef5ab7f097f73c601e7a (diff)
downloadlinux-57128468080a8b6ea452223036d3e417f748af55.tar.xz
kvm: Fix page ageing bugs
1. We were calling clear_flush_young_notify in unmap_one, but we are within an mmu notifier invalidate range scope. The spte exists no more (due to range_start) and the accessed bit info has already been propagated (due to kvm_pfn_set_accessed). Simply call clear_flush_young. 2. We clear_flush_young on a primary MMU PMD, but this may be mapped as a collection of PTEs by the secondary MMU (e.g. during log-dirty). This required expanding the interface of the clear_flush_young mmu notifier, so a lot of code has been trivially touched. 3. In the absence of shadow_accessed_mask (e.g. EPT A bit), we emulate the access bit by blowing the spte. This requires proper synchronizing with MMU notifier consumers, like every other removal of spte's does. Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'include/linux/mmu_notifier.h')
-rw-r--r--include/linux/mmu_notifier.h24
1 files changed, 17 insertions, 7 deletions
diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index 27288692241e..88787bb4b3b9 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -57,10 +57,13 @@ struct mmu_notifier_ops {
* pte. This way the VM will provide proper aging to the
* accesses to the page through the secondary MMUs and not
* only to the ones through the Linux pte.
+ * Start-end is necessary in case the secondary MMU is mapping the page
+ * at a smaller granularity than the primary MMU.
*/
int (*clear_flush_young)(struct mmu_notifier *mn,
struct mm_struct *mm,
- unsigned long address);
+ unsigned long start,
+ unsigned long end);
/*
* test_young is called to check the young/accessed bitflag in
@@ -175,7 +178,8 @@ extern void mmu_notifier_unregister_no_release(struct mmu_notifier *mn,
extern void __mmu_notifier_mm_destroy(struct mm_struct *mm);
extern void __mmu_notifier_release(struct mm_struct *mm);
extern int __mmu_notifier_clear_flush_young(struct mm_struct *mm,
- unsigned long address);
+ unsigned long start,
+ unsigned long end);
extern int __mmu_notifier_test_young(struct mm_struct *mm,
unsigned long address);
extern void __mmu_notifier_change_pte(struct mm_struct *mm,
@@ -194,10 +198,11 @@ static inline void mmu_notifier_release(struct mm_struct *mm)
}
static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm,
- unsigned long address)
+ unsigned long start,
+ unsigned long end)
{
if (mm_has_notifiers(mm))
- return __mmu_notifier_clear_flush_young(mm, address);
+ return __mmu_notifier_clear_flush_young(mm, start, end);
return 0;
}
@@ -255,7 +260,9 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
unsigned long ___address = __address; \
__young = ptep_clear_flush_young(___vma, ___address, __ptep); \
__young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \
- ___address); \
+ ___address, \
+ ___address + \
+ PAGE_SIZE); \
__young; \
})
@@ -266,7 +273,9 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
unsigned long ___address = __address; \
__young = pmdp_clear_flush_young(___vma, ___address, __pmdp); \
__young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \
- ___address); \
+ ___address, \
+ ___address + \
+ PMD_SIZE); \
__young; \
})
@@ -301,7 +310,8 @@ static inline void mmu_notifier_release(struct mm_struct *mm)
}
static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm,
- unsigned long address)
+ unsigned long start,
+ unsigned long end)
{
return 0;
}