[PATCH v3 36/66] fs/exec: Use vma_next() instead of linked list

[Liam Howlett]

From: "Liam R. Howlett" <Liam.Howlett at Oracle.com>

Signed-off-by: Liam R. Howlett <Liam.Howlett at Oracle.com>
---
 fs/exec.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c
index c618a55a20d3..75d68ff856a1 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -680,6 +680,7 @@ static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift)
 	unsigned long length = old_end - old_start;
 	unsigned long new_start = old_start - shift;
 	unsigned long new_end = old_end - shift;
+	struct vm_area_struct *next;
 	struct mmu_gather tlb;
 
 	BUG_ON(new_start > new_end);
@@ -707,12 +708,13 @@ static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift)
 
 	lru_add_drain();
 	tlb_gather_mmu(&tlb, mm);
+	next = vma_next(mm, vma);
 	if (new_end > old_start) {
 		/*
 		 * when the old and new regions overlap clear from new_end.
 		 */
 		free_pgd_range(&tlb, new_end, old_end, new_end,
-			vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
+			next ? next->vm_start : USER_PGTABLES_CEILING);
 	} else {
 		/*
 		 * otherwise, clean from old_start; this is done to not touch
@@ -721,7 +723,7 @@ static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift)
 		 * for the others its just a little faster.
 		 */
 		free_pgd_range(&tlb, old_start, old_end, new_end,
-			vma->vm_next ? vma->vm_next->vm_start : USER_PGTABLES_CEILING);
+			next ? next->vm_start : USER_PGTABLES_CEILING);
 	}
 	tlb_finish_mmu(&tlb);
 
-- 
2.30.2