#define _LINUX_RMAP_H
/*
* Declarations for Reverse Mapping functions in mm/rmap.c
- * Its structures are declared within that file.
*/
-#include <linux/config.h>
-#include <linux/linkage.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/spinlock.h>
-#define rmap_lock(page) \
- bit_spin_lock(PG_maplock, (unsigned long *)&(page)->flags)
-#define rmap_unlock(page) \
- bit_spin_unlock(PG_maplock, (unsigned long *)&(page)->flags)
+/*
+ * The anon_vma heads a list of private "related" vmas, to scan if
+ * an anonymous page pointing to this anon_vma needs to be unmapped:
+ * the vmas on the list will be related by forking, or by splitting.
+ *
+ * Since vmas come and go as they are split and merged (particularly
+ * in mprotect), the mapping field of an anonymous page cannot point
+ * directly to a vma: instead it points to an anon_vma, on whose list
+ * the related vmas can be easily linked or unlinked.
+ *
+ * After unlinking the last vma on the list, we must garbage collect
+ * the anon_vma object itself: we're guaranteed no page can be
+ * pointing to this anon_vma once its vma list is empty.
+ */
+struct anon_vma {
+ spinlock_t lock; /* Serialize access to vma list */
+ struct list_head head; /* List of private "related" vmas */
+};
#ifdef CONFIG_MMU
-struct pte_chain;
-struct pte_chain *pte_chain_alloc(int gfp_flags);
-void __pte_chain_free(struct pte_chain *pte_chain);
+extern struct kmem_cache *anon_vma_cachep;
+
+static inline struct anon_vma *anon_vma_alloc(void)
+{
+ return kmem_cache_alloc(anon_vma_cachep, GFP_KERNEL);
+}
-static inline void pte_chain_free(struct pte_chain *pte_chain)
+static inline void anon_vma_free(struct anon_vma *anon_vma)
{
- if (pte_chain)
- __pte_chain_free(pte_chain);
+ kmem_cache_free(anon_vma_cachep, anon_vma);
}
-struct pte_chain * fastcall
- page_add_rmap(struct page *, pte_t *, struct pte_chain *);
-void fastcall page_remove_rmap(struct page *, pte_t *);
+static inline void anon_vma_lock(struct vm_area_struct *vma)
+{
+ struct anon_vma *anon_vma = vma->anon_vma;
+ if (anon_vma)
+ spin_lock(&anon_vma->lock);
+}
+
+static inline void anon_vma_unlock(struct vm_area_struct *vma)
+{
+ struct anon_vma *anon_vma = vma->anon_vma;
+ if (anon_vma)
+ spin_unlock(&anon_vma->lock);
+}
+
+/*
+ * anon_vma helper functions.
+ */
+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 __anon_vma_link(struct vm_area_struct *);
+
+/*
+ * rmap interfaces called when adding or removing pte of page
+ */
+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 *);
+void page_remove_rmap(struct page *, struct vm_area_struct *);
+
+/**
+ * page_dup_rmap - duplicate pte mapping to a page
+ * @page: the page to add the mapping to
+ *
+ * For copy_page_range only: minimal extract from page_add_rmap,
+ * avoiding unnecessary tests (already checked) so it's quicker.
+ */
+static inline void page_dup_rmap(struct page *page)
+{
+ atomic_inc(&page->_mapcount);
+}
/*
* Called from mm/vmscan.c to handle paging out
*/
-int fastcall page_referenced(struct page *);
-int fastcall try_to_unmap(struct page *);
+int page_referenced(struct page *, int is_locked);
+int try_to_unmap(struct page *, int ignore_refs);
+
+/*
+ * Called from mm/filemap_xip.c to unmap empty zero page
+ */
+pte_t *page_check_address(struct page *, struct mm_struct *,
+ unsigned long, spinlock_t **);
+
+/*
+ * Used by swapoff to help locate where page is expected in vma.
+ */
+unsigned long page_address_in_vma(struct page *, struct vm_area_struct *);
+
+/*
+ * Cleans the PTEs of shared mappings.
+ * (and since clean PTEs should also be readonly, write protects them too)
+ *
+ * returns the number of cleaned PTEs.
+ */
+int page_mkclean(struct page *);
#else /* !CONFIG_MMU */
-#define page_referenced(page) TestClearPageReferenced(page)
-#define try_to_unmap(page) SWAP_FAIL
+#define anon_vma_init() do {} while (0)
+#define anon_vma_prepare(vma) (0)
+#define anon_vma_link(vma) do {} while (0)
+
+#define page_referenced(page,l) TestClearPageReferenced(page)
+#define try_to_unmap(page, refs) SWAP_FAIL
+
+static inline int page_mkclean(struct page *page)
+{
+ return 0;
+}
+
#endif /* CONFIG_MMU */
git://git.onelab.eu / linux-2.6.git / blobdiff