[PATCH v14 59/70] mm/mremap: use vma_find_intersection() instead of vma linked list

From: Liam Howlett
Date: Tue Sep 06 2022 - 15:54:23 EST


From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>

Using the vma_find_intersection() call allows for cleaner code and
removes linked list users in preparation of the linked list removal.

Also remove one user of the linked list at the same time in favour of
find_vma().

Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: Davidlohr Bueso <dave@xxxxxxxxxxxx>
---
mm/mremap.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/mremap.c b/mm/mremap.c
index e0fba9004246..8644ff278f02 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -716,7 +716,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
if (excess) {
vma->vm_flags |= VM_ACCOUNT;
if (split)
- vma->vm_next->vm_flags |= VM_ACCOUNT;
+ find_vma(mm, vma->vm_end)->vm_flags |= VM_ACCOUNT;
}

return new_addr;
@@ -866,9 +866,10 @@ static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
static int vma_expandable(struct vm_area_struct *vma, unsigned long delta)
{
unsigned long end = vma->vm_end + delta;
+
if (end < vma->vm_end) /* overflow */
return 0;
- if (vma->vm_next && vma->vm_next->vm_start < end) /* intersection */
+ if (find_vma_intersection(vma->vm_mm, vma->vm_end, end))
return 0;
if (get_unmapped_area(NULL, vma->vm_start, end - vma->vm_start,
0, MAP_FIXED) & ~PAGE_MASK)
--
2.35.1