[PATCH] mm: Change count_mm_mlocked_page_nr return type

[Weikang shi]

From: swkhack <swkh...@gmail.com>

In 64-bit machine,the value of "vma->vm_end - vma->vm_start"
maybe negative in 32bit int and the "count >> PAGE_SHIFT"'s result
will be wrong.So change the local variable and return
value to unsigned long will fix the problem.

Signed-off-by: swkhack <swkh...@gmail.com>
---
 mm/mlock.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/mlock.c b/mm/mlock.c
index 080f3b364..d614163f5 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -636,11 +636,11 @@ static int apply_vma_lock_flags(unsigned long start, 
size_t len,
  * is also counted.
  * Return value: previously mlocked page counts
  */
-static int count_mm_mlocked_page_nr(struct mm_struct *mm,
+static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm,
                unsigned long start, size_t len)
 {
        struct vm_area_struct *vma;
-       int count = 0;
+       unsigned long count = 0;
 
        if (mm == NULL)
                mm = current->mm;
-- 
2.17.1