mm: thp: calculate the mapcount correctly for THP pages during WP faults

[karo-tx-linux.git] / include / linux / mm.h

diff --git a/include/linux/mm.h b/include/linux/mm.h
index a55e5be0894f44d01145a0f3fc6d9c6b011e5754..8f468e0d2534eddaa178fdf252e7cf4e53f3330b 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -500,11 +500,20 @@ static inline int page_mapcount(struct page *page)
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 int total_mapcount(struct page *page);
+int page_trans_huge_mapcount(struct page *page, int *total_mapcount);
 #else
 static inline int total_mapcount(struct page *page)
 {
        return page_mapcount(page);
 }
+static inline int page_trans_huge_mapcount(struct page *page,
+                                          int *total_mapcount)
+{
+       int mapcount = page_mapcount(page);
+       if (total_mapcount)
+               *total_mapcount = mapcount;
+       return mapcount;
+}
 #endif
 
 static inline struct page *virt_to_head_page(const void *x)
@@ -1031,6 +1040,8 @@ static inline bool page_mapped(struct page *page)
        page = compound_head(page);
        if (atomic_read(compound_mapcount_ptr(page)) >= 0)
                return true;
+       if (PageHuge(page))
+               return false;
        for (i = 0; i < hpage_nr_pages(page); i++) {
                if (atomic_read(&page[i]._mapcount) >= 0)
                        return true;
@@ -1138,6 +1149,8 @@ struct zap_details {
 
 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
                pte_t pte);
+struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
+                               pmd_t pmd);
 
 int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
                unsigned long size);