diff options
Diffstat (limited to 'include/linux/rmap.h')
| -rw-r--r-- | include/linux/rmap.h | 81 |
1 files changed, 76 insertions, 5 deletions
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index cb0ba7032609..d25bd224d370 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -26,6 +26,9 @@ */ struct anon_vma { spinlock_t lock; /* Serialize access to vma list */ +#ifdef CONFIG_KSM + atomic_t ksm_refcount; +#endif /* * NOTE: the LSB of the head.next is set by * mm_take_all_locks() _after_ taking the above lock. So the @@ -34,10 +37,58 @@ struct anon_vma { * is serialized by a system wide lock only visible to * mm_take_all_locks() (mm_all_locks_mutex). */ - struct list_head head; /* List of private "related" vmas */ + struct list_head head; /* Chain of private "related" vmas */ +}; + +/* + * The copy-on-write semantics of fork mean that an anon_vma + * can become associated with multiple processes. Furthermore, + * each child process will have its own anon_vma, where new + * pages for that process are instantiated. + * + * This structure allows us to find the anon_vmas associated + * with a VMA, or the VMAs associated with an anon_vma. + * The "same_vma" list contains the anon_vma_chains linking + * all the anon_vmas associated with this VMA. + * The "same_anon_vma" list contains the anon_vma_chains + * which link all the VMAs associated with this anon_vma. + */ +struct anon_vma_chain { + struct vm_area_struct *vma; + struct anon_vma *anon_vma; + struct list_head same_vma; /* locked by mmap_sem & page_table_lock */ + struct list_head same_anon_vma; /* locked by anon_vma->lock */ }; #ifdef CONFIG_MMU +#ifdef CONFIG_KSM +static inline void ksm_refcount_init(struct anon_vma *anon_vma) +{ + atomic_set(&anon_vma->ksm_refcount, 0); +} + +static inline int ksm_refcount(struct anon_vma *anon_vma) +{ + return atomic_read(&anon_vma->ksm_refcount); +} +#else +static inline void ksm_refcount_init(struct anon_vma *anon_vma) +{ +} + +static inline int ksm_refcount(struct anon_vma *anon_vma) +{ + return 0; +} +#endif /* CONFIG_KSM */ + +static inline struct anon_vma *page_anon_vma(struct page *page) +{ + if (((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != + PAGE_MAPPING_ANON) + return NULL; + return page_rmapping(page); +} static inline void anon_vma_lock(struct vm_area_struct *vma) { @@ -58,14 +109,23 @@ static inline void anon_vma_unlock(struct vm_area_struct *vma) */ void anon_vma_init(void); /* create anon_vma_cachep */ int anon_vma_prepare(struct vm_area_struct *); -void __anon_vma_merge(struct vm_area_struct *, struct vm_area_struct *); -void anon_vma_unlink(struct vm_area_struct *); -void anon_vma_link(struct vm_area_struct *); +void unlink_anon_vmas(struct vm_area_struct *); +int anon_vma_clone(struct vm_area_struct *, struct vm_area_struct *); +int anon_vma_fork(struct vm_area_struct *, struct vm_area_struct *); void __anon_vma_link(struct vm_area_struct *); +void anon_vma_free(struct anon_vma *); + +static inline void anon_vma_merge(struct vm_area_struct *vma, + struct vm_area_struct *next) +{ + VM_BUG_ON(vma->anon_vma != next->anon_vma); + unlink_anon_vmas(next); +} /* * rmap interfaces called when adding or removing pte of page */ +void page_move_anon_rmap(struct page *, struct vm_area_struct *, unsigned long); void page_add_anon_rmap(struct page *, struct vm_area_struct *, unsigned long); void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, unsigned long); void page_add_file_rmap(struct page *); @@ -81,6 +141,9 @@ static inline void page_dup_rmap(struct page *page) */ int page_referenced(struct page *, int is_locked, struct mem_cgroup *cnt, unsigned long *vm_flags); +int page_referenced_one(struct page *, struct vm_area_struct *, + unsigned long address, unsigned int *mapcount, unsigned long *vm_flags); + enum ttu_flags { TTU_UNMAP = 0, /* unmap mode */ TTU_MIGRATION = 1, /* migration mode */ @@ -94,6 +157,8 @@ enum ttu_flags { #define TTU_ACTION(x) ((x) & TTU_ACTION_MASK) int try_to_unmap(struct page *, enum ttu_flags flags); +int try_to_unmap_one(struct page *, struct vm_area_struct *, + unsigned long address, enum ttu_flags flags); /* * Called from mm/filemap_xip.c to unmap empty zero page @@ -127,6 +192,12 @@ struct anon_vma *page_lock_anon_vma(struct page *page); void page_unlock_anon_vma(struct anon_vma *anon_vma); int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma); +/* + * Called by migrate.c to remove migration ptes, but might be used more later. + */ +int rmap_walk(struct page *page, int (*rmap_one)(struct page *, + struct vm_area_struct *, unsigned long, void *), void *arg); + #else /* !CONFIG_MMU */ #define anon_vma_init() do {} while (0) @@ -138,7 +209,7 @@ static inline int page_referenced(struct page *page, int is_locked, unsigned long *vm_flags) { *vm_flags = 0; - return TestClearPageReferenced(page); + return 0; } #define try_to_unmap(page, refs) SWAP_FAIL |