1 files changed, 22 insertions, 5 deletions

diff --git a/mm/fremap.c b/mm/fremap.c
index 7881638e4a12..7d12ca70ef7b 100644
--- a/mm/fremap.c
+++ b/mm/fremap.c
@@ -21,6 +21,8 @@
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 
+#include "internal.h"
+
 static void zap_pte(struct mm_struct *mm, struct vm_area_struct *vma,
                         unsigned long addr, pte_t *ptep)
 {
@@ -215,15 +217,31 @@ asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size,
                 spin_unlock(&mapping->i_mmap_lock);
         }
 
+        if (vma->vm_flags & VM_LOCKED) {
+                /*
+                 * drop PG_Mlocked flag for over-mapped range
+                 */
+                unsigned int saved_flags = vma->vm_flags;
+                munlock_vma_pages_range(vma, start, start + size);
+                vma->vm_flags = saved_flags;
+        }
+
         mmu_notifier_invalidate_range_start(mm, start, start + size);
         err = populate_range(mm, vma, start, size, pgoff);
         mmu_notifier_invalidate_range_end(mm, start, start + size);
         if (!err && !(flags & MAP_NONBLOCK)) {
-                if (unlikely(has_write_lock)) {
-                        downgrade_write(&mm->mmap_sem);
-                        has_write_lock = 0;
+                if (vma->vm_flags & VM_LOCKED) {
+                        /*
+                         * might be mapping previously unmapped range of file
+                         */
+                        mlock_vma_pages_range(vma, start, start + size);
+                } else {
+                        if (unlikely(has_write_lock)) {
+                                downgrade_write(&mm->mmap_sem);
+                                has_write_lock = 0;
+                        }
+                        make_pages_present(start, start+size);
                 }
-                make_pages_present(start, start+size);
         }
 
         /*
@@ -240,4 +258,3 @@ out:
 
         return err;
 }
-