[PATCH v3 20/48] mempolicy: Convert to vma iterator

Liam Howlett
2023-01-17T02:35:30Z

Use the vma iterator so that the iterator can be invalidated or updated
to avoid each caller doing so.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
mm/mempolicy.c | 25 ++++++++-----------------
1 file changed, 8 insertions(+), 17 deletions(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 02c8a712282f..6f41a30c24d5 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -787,24 +787,21 @@ static int vma_replace_policy(struct vm_area_struct *vma,
static int mbind_range(struct mm_struct *mm, unsigned long start,
unsigned long end, struct mempolicy *new_pol)
{
- MA_STATE(mas, &mm->mm_mt, start, start);
+ VMA_ITERATOR(vmi, mm, start);
struct vm_area_struct *prev;
struct vm_area_struct *vma;
int err = 0;
pgoff_t pgoff;

- prev = mas_prev(&mas, 0);
- if (unlikely(!prev))
- mas_set(&mas, start);
-
- vma = mas_find(&mas, end - 1);
+ prev = vma_prev(&vmi);
+ vma = vma_find(&vmi, end);
if (WARN_ON(!vma))
return 0;

if (start > vma->vm_start)
prev = vma;

- for (; vma; vma = mas_next(&mas, end - 1)) {
+ do {
unsigned long vmstart = max(start, vma->vm_start);
unsigned long vmend = min(end, vma->vm_end);

@@ -813,29 +810,23 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,

pgoff = vma->vm_pgoff +
((vmstart - vma->vm_start) >> PAGE_SHIFT);
- prev = vma_merge(mm, prev, vmstart, vmend, vma->vm_flags,
+ prev = vmi_vma_merge(&vmi, mm, prev, vmstart, vmend, vma->vm_flags,
vma->anon_vma, vma->vm_file, pgoff,
new_pol, vma->vm_userfaultfd_ctx,
anon_vma_name(vma));
if (prev) {
- /* vma_merge() invalidated the mas */
- mas_pause(&mas);
vma = prev;
goto replace;
}
if (vma->vm_start != vmstart) {
- err = split_vma(vma->vm_mm, vma, vmstart, 1);
+ err = vmi_split_vma(&vmi, vma->vm_mm, vma, vmstart, 1);
if (err)
goto out;
- /* split_vma() invalidated the mas */
- mas_pause(&mas);
}
if (vma->vm_end != vmend) {
- err = split_vma(vma->vm_mm, vma, vmend, 0);
+ err = vmi_split_vma(&vmi, vma->vm_mm, vma, vmend, 0);
if (err)
goto out;
- /* split_vma() invalidated the mas */
- mas_pause(&mas);
}
replace:
err = vma_replace_policy(vma, new_pol);
@@ -843,7 +834,7 @@ static int mbind_range(struct mm_struct *mm, unsigned long start,
goto out;
next:
prev = vma;
- }
+ } for_each_vma_range(vmi, vma, end);

out:
return err;
--
2.35.1