[PATCH v6 07/20] mm/vma: Extract validate_mm() from vma_complete()

["Liam R. Howlett" <Liam.Howlett@oracle.com>]

From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>

vma_complete() will need to be called during an unsafe time to call
validate_mm().  Extract the call in all places now so that only one
location can be modified in the next change.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
---
 mm/mmap.c | 1 +
 mm/vma.c  | 5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index 30ae4cb5cec9..112f2111c457 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1796,6 +1796,7 @@ static int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma,
 		vma_iter_store(vmi, vma);
 
 		vma_complete(&vp, vmi, mm);
+		validate_mm(mm);
 		khugepaged_enter_vma(vma, flags);
 		goto out;
 	}
diff --git a/mm/vma.c b/mm/vma.c
index 7b8b8b983399..5abda4c49c83 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -269,6 +269,7 @@ 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);
+	validate_mm(vma->vm_mm);
 
 	/* Success. */
 	if (new_below)
@@ -548,6 +549,7 @@ int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma,
 	vma_iter_store(vmi, vma);
 
 	vma_complete(&vp, vmi, vma->vm_mm);
+	validate_mm(vma->vm_mm);
 	return 0;
 
 nomem:
@@ -589,6 +591,7 @@ 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);
+	validate_mm(vma->vm_mm);
 	return 0;
 }
 
@@ -668,7 +671,6 @@ void vma_complete(struct vma_prepare *vp,
 	}
 	if (vp->insert && vp->file)
 		uprobe_mmap(vp->insert);
-	validate_mm(mm);
 }
 
 /*
@@ -1200,6 +1202,7 @@ static struct vm_area_struct
 	}
 
 	vma_complete(&vp, vmi, mm);
+	validate_mm(mm);
 	khugepaged_enter_vma(res, vm_flags);
 	return res;
 
-- 
2.43.0