1 files changed, 10 insertions, 16 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 6bef278ad303..655e1429388a 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1055,7 +1055,7 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
         if (is_vm_hugetlb_page(vma))
                 return copy_hugetlb_page_range(dst_mm, src_mm, vma);
 
-        if (unlikely(is_pfn_mapping(vma))) {
+        if (unlikely(vma->vm_flags & VM_PFNMAP)) {
                 /*
                  * We do not free on error cases below as remove_vma
                  * gets called on error from higher level routine
@@ -1327,7 +1327,7 @@ static void unmap_single_vma(struct mmu_gather *tlb,
         if (vma->vm_file)
                 uprobe_munmap(vma, start, end);
 
-        if (unlikely(is_pfn_mapping(vma)))
+        if (unlikely(vma->vm_flags & VM_PFNMAP))
                 untrack_pfn(vma, 0, 0);
 
         if (start != end) {
@@ -2299,26 +2299,20 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
          * There's a horrible special case to handle copy-on-write
          * behaviour that some programs depend on. We mark the "original"
          * un-COW'ed pages by matching them up with "vma->vm_pgoff".
+         * See vm_normal_page() for details.
          */
-        if (addr == vma->vm_start && end == vma->vm_end) {
+        if (is_cow_mapping(vma->vm_flags)) {
+                if (addr != vma->vm_start || end != vma->vm_end)
+                        return -EINVAL;
                 vma->vm_pgoff = pfn;
-                vma->vm_flags |= VM_PFN_AT_MMAP;
-        } else if (is_cow_mapping(vma->vm_flags))
+        }
+
+        err = track_pfn_remap(vma, &prot, pfn, addr, PAGE_ALIGN(size));
+        if (err)
                 return -EINVAL;
 
         vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
 
-        err = track_pfn_remap(vma, &prot, pfn, PAGE_ALIGN(size));
-        if (err) {
-                /*
-                 * To indicate that track_pfn related cleanup is not
-                 * needed from higher level routine calling unmap_vmas
-                 */
-                vma->vm_flags &= ~(VM_IO | VM_RESERVED | VM_PFNMAP);
-                vma->vm_flags &= ~VM_PFN_AT_MMAP;
-                return -EINVAL;
-        }
-
         BUG_ON(addr >= end);
         pfn -= addr >> PAGE_SHIFT;
         pgd = pgd_offset(mm, addr);