summaryrefslogtreecommitdiff
path: root/mm/hugetlb.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r--mm/hugetlb.c22
1 files changed, 12 insertions, 10 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 2cd4c7f43dcd..4033b6ce01c4 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4902,21 +4902,23 @@ static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr)
void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma,
unsigned long *start, unsigned long *end)
{
- unsigned long a_start, a_end;
+ unsigned long v_start = ALIGN(vma->vm_start, PUD_SIZE),
+ v_end = ALIGN_DOWN(vma->vm_end, PUD_SIZE);
- if (!(vma->vm_flags & VM_MAYSHARE))
+ /*
+ * vma need span at least one aligned PUD size and the start,end range
+ * must at least partialy within it.
+ */
+ if (!(vma->vm_flags & VM_MAYSHARE) || !(v_end > v_start) ||
+ (*end <= v_start) || (*start >= v_end))
return;
/* Extend the range to be PUD aligned for a worst case scenario */
- a_start = ALIGN_DOWN(*start, PUD_SIZE);
- a_end = ALIGN(*end, PUD_SIZE);
+ if (*start > v_start)
+ *start = ALIGN_DOWN(*start, PUD_SIZE);
- /*
- * Intersect the range with the vma range, since pmd sharing won't be
- * across vma after all
- */
- *start = max(vma->vm_start, a_start);
- *end = min(vma->vm_end, a_end);
+ if (*end < v_end)
+ *end = ALIGN(*end, PUD_SIZE);
}
/*