[PATCH] add page_mkwrite() vm_operations method

[pandora-kernel.git] / include / linux / mm.h

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 6aa016f..3b09444 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -7,7 +7,6 @@
 
 #ifdef __KERNEL__
 
-#include <linux/config.h>
 #include <linux/gfp.h>
 #include <linux/list.h>
 #include <linux/mmzone.h>
@@ -200,6 +199,10 @@ struct vm_operations_struct {
        void (*close)(struct vm_area_struct * area);
        struct page * (*nopage)(struct vm_area_struct * area, unsigned long address, int *type);
        int (*populate)(struct vm_area_struct * area, unsigned long address, unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock);
+
+       /* notification that a previously read-only page is about to become
+        * writable, if an error is returned it will cause a SIGBUS */
+       int (*page_mkwrite)(struct vm_area_struct *vma, struct page *page);
 #ifdef CONFIG_NUMA
        int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
        struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
@@ -229,10 +232,9 @@ struct page {
                unsigned long private;          /* Mapping-private opaque data:
                                                 * usually used for buffer_heads
                                                 * if PagePrivate set; used for
-                                                * swp_entry_t if PageSwapCache.
-                                                * When page is free, this
+                                                * swp_entry_t if PageSwapCache;
                                                 * indicates order in the buddy
-                                                * system.
+                                                * system if PG_buddy is set.
                                                 */
                struct address_space *mapping;  /* If low bit clear, points to
                                                 * inode address_space, or NULL.
@@ -467,10 +469,13 @@ static inline unsigned long page_zonenum(struct page *page)
 struct zone;
 extern struct zone *zone_table[];
 
+static inline int page_zone_id(struct page *page)
+{
+       return (page->flags >> ZONETABLE_PGSHIFT) & ZONETABLE_MASK;
+}
 static inline struct zone *page_zone(struct page *page)
 {
-       return zone_table[(page->flags >> ZONETABLE_PGSHIFT) &
-                       ZONETABLE_MASK];
+       return zone_table[page_zone_id(page)];
 }
 
 static inline unsigned long page_to_nid(struct page *page)