[PATCH] mm/mmap: remove the mm parameter in vma_complete()

From: Yajun Deng
Date: Mon Jan 29 2024 - 02:56:34 EST


There are vma_merge() and do_brk_flags() pass mm to vma_complete(), others
would pass the vma->vm_mm. The following explains that the mm is the
vma->vm_mm in vma_merge() and do_brk_flags().

All vma will point to the same mm struct if the vma_merge() is successful.
So the mm and the vma->mm are the same.

vm_brk_flags() and brk syscall will initialize vmi with current->mm,
so the vma->vm_mm and the current->mm are the same if vma exists in
do_brk_flags().

Remove the mm parameter in vma_complete() and get mm from the vma in vp.

Signed-off-by: Yajun Deng <yajun.deng@xxxxxxxxx>
---
mm/mmap.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index e97b9144c61a..9b968d1edf55 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -509,11 +509,11 @@ static inline void vma_prepare(struct vma_prepare *vp)
*
* @vp: The vma_prepare struct
* @vmi: The vma iterator
- * @mm: The mm_struct
*/
-static inline void vma_complete(struct vma_prepare *vp,
- struct vma_iterator *vmi, struct mm_struct *mm)
+static inline void vma_complete(struct vma_prepare *vp, struct vma_iterator *vmi)
{
+ struct mm_struct *mm = vp->vma->vm_mm;
+
if (vp->file) {
if (vp->adj_next)
vma_interval_tree_insert(vp->adj_next,
@@ -666,7 +666,7 @@ int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma,
vma_set_range(vma, start, end, pgoff);
vma_iter_store(vmi, vma);

- vma_complete(&vp, vmi, vma->vm_mm);
+ vma_complete(&vp, vmi);
return 0;

nomem:
@@ -707,7 +707,7 @@ int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,

vma_iter_clear(vmi);
vma_set_range(vma, start, end, pgoff);
- vma_complete(&vp, vmi, vma->vm_mm);
+ vma_complete(&vp, vmi);
return 0;
}

@@ -1030,7 +1030,7 @@ static struct vm_area_struct
}
}

- vma_complete(&vp, vmi, mm);
+ vma_complete(&vp, vmi);
khugepaged_enter_vma(res, vm_flags);
return res;

@@ -2377,7 +2377,7 @@ static int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
}

/* vma_complete stores the new vma */
- vma_complete(&vp, vmi, vma->vm_mm);
+ vma_complete(&vp, vmi);

/* Success. */
if (new_below)
@@ -3145,7 +3145,7 @@ static int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma,
vm_flags_set(vma, VM_SOFTDIRTY);
vma_iter_store(vmi, vma);

- vma_complete(&vp, vmi, mm);
+ vma_complete(&vp, vmi);
khugepaged_enter_vma(vma, flags);
goto out;
}
--
2.25.1