mempolicy: convert to vma iterator

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

Link: https://lkml.kernel.org/r/20230120162650.984577-21-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Liam R. Howlett 2023-01-20 11:26:21 -05:00 committed by Andrew Morton
parent e552cdb853
commit f10c2abcda

View File

@ -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 @@ replace:
goto out;
next:
prev = vma;
}
} for_each_vma_range(vmi, vma, end);
out:
return err;