[PATCH v3 39/48] mm/mmap: move anon_vma setting in __vma_adjust()

Liam Howlett
2023-01-17T02:39:35Z

Move the anon_vma setting & warn_no up the function. This is done to
clear up the locking later.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
mm/mmap.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index 434020155f8a..90638fa48734 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -685,6 +685,14 @@ int __vma_adjust(struct vma_iterator *vmi, struct vm_area_struct *vma,
if (vma_iter_prealloc(vmi, vma))
return -ENOMEM;

+ anon_vma = vma->anon_vma;
+ if (!anon_vma && adjust_next)
+ anon_vma = next->anon_vma;
+
+ if (anon_vma)
+ VM_WARN_ON(adjust_next && next->anon_vma &&
+ anon_vma != next->anon_vma);
+
vma_adjust_trans_huge(orig_vma, start, end, adjust_next);
if (file) {
mapping = file->f_mapping;
@@ -706,12 +714,7 @@ int __vma_adjust(struct vma_iterator *vmi, struct vm_area_struct *vma,
}
}

- anon_vma = vma->anon_vma;
- if (!anon_vma && adjust_next)
- anon_vma = next->anon_vma;
if (anon_vma) {
- VM_WARN_ON(adjust_next && next->anon_vma &&
- anon_vma != next->anon_vma);
anon_vma_lock_write(anon_vma);
anon_vma_interval_tree_pre_update_vma(vma);
if (adjust_next)
--
2.35.1