Merge to Fedora kernel-2.6.18-1.2224_FC5 patched with stable patch-2.6.18.1-vs2.0...

[linux-2.6.git] / include / linux / swapops.h

diff --git a/include/linux/swapops.h b/include/linux/swapops.h
index 87b9d14..ec639aa 100644 (file)
--- a/include/linux/swapops.h
+++ b/include/linux/swapops.h
@@ -67,3 +67,56 @@ static inline pte_t swp_entry_to_pte(swp_entry_t entry)
        BUG_ON(pte_file(__swp_entry_to_pte(arch_entry)));
        return __swp_entry_to_pte(arch_entry);
 }
+
+#ifdef CONFIG_MIGRATION
+static inline swp_entry_t make_migration_entry(struct page *page, int write)
+{
+       BUG_ON(!PageLocked(page));
+       return swp_entry(write ? SWP_MIGRATION_WRITE : SWP_MIGRATION_READ,
+                       page_to_pfn(page));
+}
+
+static inline int is_migration_entry(swp_entry_t entry)
+{
+       return unlikely(swp_type(entry) == SWP_MIGRATION_READ ||
+                       swp_type(entry) == SWP_MIGRATION_WRITE);
+}
+
+static inline int is_write_migration_entry(swp_entry_t entry)
+{
+       return unlikely(swp_type(entry) == SWP_MIGRATION_WRITE);
+}
+
+static inline struct page *migration_entry_to_page(swp_entry_t entry)
+{
+       struct page *p = pfn_to_page(swp_offset(entry));
+       /*
+        * Any use of migration entries may only occur while the
+        * corresponding page is locked
+        */
+       BUG_ON(!PageLocked(p));
+       return p;
+}
+
+static inline void make_migration_entry_read(swp_entry_t *entry)
+{
+       *entry = swp_entry(SWP_MIGRATION_READ, swp_offset(*entry));
+}
+
+extern void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd,
+                                       unsigned long address);
+#else
+
+#define make_migration_entry(page, write) swp_entry(0, 0)
+#define is_migration_entry(swp) 0
+#define migration_entry_to_page(swp) NULL
+static inline void make_migration_entry_read(swp_entry_t *entryp) { }
+static inline void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd,
+                                        unsigned long address) { }
+static inline int is_write_migration_entry(swp_entry_t entry)
+{
+       return 0;
+}
+
+#endif
+