1 files changed, 48 insertions, 4 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 1bba6789a50a..e8abb3814209 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -227,10 +227,22 @@ static inline int put_page_testzero(struct page *page)
  */
 static inline int get_page_unless_zero(struct page *page)
 {
-        VM_BUG_ON(PageCompound(page));
+        VM_BUG_ON(PageTail(page));
         return atomic_inc_not_zero(&page->_count);
 }
 
+/* Support for virtually mapped pages */
+struct page *vmalloc_to_page(const void *addr);
+unsigned long vmalloc_to_pfn(const void *addr);
+
+/* Determine if an address is within the vmalloc range */
+static inline int is_vmalloc_addr(const void *x)
+{
+        unsigned long addr = (unsigned long)x;
+
+        return addr >= VMALLOC_START && addr < VMALLOC_END;
+}
+
 static inline struct page *compound_head(struct page *page)
 {
         if (unlikely(PageTail(page)))
@@ -706,6 +718,28 @@ unsigned long unmap_vmas(struct mmu_gather **tlb,
                 struct vm_area_struct *start_vma, unsigned long start_addr,
                 unsigned long end_addr, unsigned long *nr_accounted,
                 struct zap_details *);
+
+/**
+ * mm_walk - callbacks for walk_page_range
+ * @pgd_entry: if set, called for each non-empty PGD (top-level) entry
+ * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
+ * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
+ * @pte_entry: if set, called for each non-empty PTE (4th-level) entry
+ * @pte_hole: if set, called for each hole at all levels
+ *
+ * (see walk_page_range for more details)
+ */
+struct mm_walk {
+        int (*pgd_entry)(pgd_t *, unsigned long, unsigned long, void *);
+        int (*pud_entry)(pud_t *, unsigned long, unsigned long, void *);
+        int (*pmd_entry)(pmd_t *, unsigned long, unsigned long, void *);
+        int (*pte_entry)(pte_t *, unsigned long, unsigned long, void *);
+        int (*pte_hole)(unsigned long, unsigned long, void *);
+};
+
+int walk_page_range(const struct mm_struct *, unsigned long addr,
+                    unsigned long end, const struct mm_walk *walk,
+                    void *private);
 void free_pgd_range(struct mmu_gather **tlb, unsigned long addr,
                 unsigned long end, unsigned long floor, unsigned long ceiling);
 void free_pgtables(struct mmu_gather **tlb, struct vm_area_struct *start_vma,
@@ -860,6 +894,18 @@ static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long a
 #define pte_lockptr(mm, pmd)    ({(void)(pmd); &(mm)->page_table_lock;})
 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
 
+static inline void pgtable_page_ctor(struct page *page)
+{
+        pte_lock_init(page);
+        inc_zone_page_state(page, NR_PAGETABLE);
+}
+
+static inline void pgtable_page_dtor(struct page *page)
+{
+        pte_lock_deinit(page);
+        dec_zone_page_state(page, NR_PAGETABLE);
+}
+
 #define pte_offset_map_lock(mm, pmd, address, ptlp)     \
 ({                                                      \
         spinlock_t *__ptl = pte_lockptr(mm, pmd);       \
@@ -1089,8 +1135,6 @@ static inline unsigned long vma_pages(struct vm_area_struct *vma)
 
 pgprot_t vm_get_page_prot(unsigned long vm_flags);
 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
-struct page *vmalloc_to_page(void *addr);
-unsigned long vmalloc_to_pfn(void *addr);
 int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
                         unsigned long pfn, unsigned long size, pgprot_t);
 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
@@ -1104,7 +1148,7 @@ struct page *follow_page(struct vm_area_struct *, unsigned long address,
 #define FOLL_GET        0x04    /* do get_page on page */
 #define FOLL_ANON       0x08    /* give ZERO_PAGE if no pgtable */
 
-typedef int (*pte_fn_t)(pte_t *pte, struct page *pmd_page, unsigned long addr,
+typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
                         void *data);
 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
                                unsigned long size, pte_fn_t fn, void *data);