diff options
| -rw-r--r-- | include/linux/mmu_notifier.h | 34 | ||||
| -rw-r--r-- | mm/memory.c | 9 | ||||
| -rw-r--r-- | mm/mmu_notifier.c | 20 |
3 files changed, 61 insertions, 2 deletions
diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h index b77486d152c..4e02ee2b071 100644 --- a/include/linux/mmu_notifier.h +++ b/include/linux/mmu_notifier.h @@ -62,6 +62,15 @@ struct mmu_notifier_ops { unsigned long address); /* + * change_pte is called in cases that pte mapping to page is changed: + * for example, when ksm remaps pte to point to a new shared page. + */ + void (*change_pte)(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long address, + pte_t pte); + + /* * Before this is invoked any secondary MMU is still ok to * read/write to the page previously pointed to by the Linux * pte because the page hasn't been freed yet and it won't be @@ -154,6 +163,8 @@ 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); +extern void __mmu_notifier_change_pte(struct mm_struct *mm, + unsigned long address, pte_t pte); extern void __mmu_notifier_invalidate_page(struct mm_struct *mm, unsigned long address); extern void __mmu_notifier_invalidate_range_start(struct mm_struct *mm, @@ -175,6 +186,13 @@ static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, return 0; } +static inline void mmu_notifier_change_pte(struct mm_struct *mm, + unsigned long address, pte_t pte) +{ + if (mm_has_notifiers(mm)) + __mmu_notifier_change_pte(mm, address, pte); +} + static inline void mmu_notifier_invalidate_page(struct mm_struct *mm, unsigned long address) { @@ -236,6 +254,16 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm) __young; \ }) +#define set_pte_at_notify(__mm, __address, __ptep, __pte) \ +({ \ + struct mm_struct *___mm = __mm; \ + unsigned long ___address = __address; \ + pte_t ___pte = __pte; \ + \ + set_pte_at(___mm, ___address, __ptep, ___pte); \ + mmu_notifier_change_pte(___mm, ___address, ___pte); \ +}) + #else /* CONFIG_MMU_NOTIFIER */ static inline void mmu_notifier_release(struct mm_struct *mm) @@ -248,6 +276,11 @@ static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, return 0; } +static inline void mmu_notifier_change_pte(struct mm_struct *mm, + unsigned long address, pte_t pte) +{ +} + static inline void mmu_notifier_invalidate_page(struct mm_struct *mm, unsigned long address) { @@ -273,6 +306,7 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm) #define ptep_clear_flush_young_notify ptep_clear_flush_young #define ptep_clear_flush_notify ptep_clear_flush +#define set_pte_at_notify set_pte_at #endif /* CONFIG_MMU_NOTIFIER */ diff --git a/mm/memory.c b/mm/memory.c index e8f63d9961e..368561f3200 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2115,9 +2115,14 @@ gotten: * seen in the presence of one thread doing SMC and another * thread doing COW. */ - ptep_clear_flush_notify(vma, address, page_table); + ptep_clear_flush(vma, address, page_table); page_add_new_anon_rmap(new_page, vma, address); - set_pte_at(mm, address, page_table, entry); + /* + * We call the notify macro here because, when using secondary + * mmu page tables (such as kvm shadow page tables), we want the + * new page to be mapped directly into the secondary page table. + */ + set_pte_at_notify(mm, address, page_table, entry); update_mmu_cache(vma, address, entry); if (old_page) { /* diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index 5f4ef0250be..7e33f2cb3c7 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -99,6 +99,26 @@ int __mmu_notifier_clear_flush_young(struct mm_struct *mm, return young; } +void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address, + pte_t pte) +{ + struct mmu_notifier *mn; + struct hlist_node *n; + + rcu_read_lock(); + hlist_for_each_entry_rcu(mn, n, &mm->mmu_notifier_mm->list, hlist) { + if (mn->ops->change_pte) + mn->ops->change_pte(mn, mm, address, pte); + /* + * Some drivers don't have change_pte, + * so we must call invalidate_page in that case. + */ + else if (mn->ops->invalidate_page) + mn->ops->invalidate_page(mn, mm, address); + } + rcu_read_unlock(); +} + void __mmu_notifier_invalidate_page(struct mm_struct *mm, unsigned long address) { |