setup vma->vm_page_prot by vm_get_page_prot()

This patch uses vm_get_page_prot() to setup vma->vm_page_prot.

Though inside vm_get_page_prot() the protection flags is AND with
(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED), it does not hurt correct code.

Signed-off-by: Coly Li <coyli@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 7 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index 4275e81e25ba..7a30c4988231 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1048,8 +1048,7 @@ int vma_wants_writenotify(struct vm_area_struct *vma)
 
         /* The open routine did something to the protections already? */
         if (pgprot_val(vma->vm_page_prot) !=
-            pgprot_val(protection_map[vm_flags &
-                    (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]))
+            pgprot_val(vm_get_page_prot(vm_flags)))
                 return 0;
 
         /* Specialty mapping? */
@@ -1130,8 +1129,7 @@ munmap_back:
         vma->vm_start = addr;
         vma->vm_end = addr + len;
         vma->vm_flags = vm_flags;
-        vma->vm_page_prot = protection_map[vm_flags &
-                                (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
+        vma->vm_page_prot = vm_get_page_prot(vm_flags);
         vma->vm_pgoff = pgoff;
 
         if (file) {
@@ -2002,8 +2000,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
         vma->vm_end = addr + len;
         vma->vm_pgoff = pgoff;
         vma->vm_flags = flags;
-        vma->vm_page_prot = protection_map[flags &
-                                (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
+        vma->vm_page_prot = vm_get_page_prot(flags);
         vma_link(mm, vma, prev, rb_link, rb_parent);
 out:
         mm->total_vm += len >> PAGE_SHIFT;
@@ -2209,7 +2206,7 @@ int install_special_mapping(struct mm_struct *mm,
         vma->vm_end = addr + len;
 
         vma->vm_flags = vm_flags | mm->def_flags;
-        vma->vm_page_prot = protection_map[vma->vm_flags & 7];
+        vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 
         vma->vm_ops = &special_mapping_vmops;
         vma->vm_private_data = pages;