[PATCH v4 2/3] mm: document locking restrictions for vm_operations_struct::close

[Suren Baghdasaryan]

Add comments for vm_operations_struct::close documenting locking
requirements for this callback and its callers.

Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
---
 include/linux/mm.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index a7e4a9e7d807..b9b88ba7564b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -577,6 +577,10 @@ enum page_entry_size {
  */
 struct vm_operations_struct {
 	void (*open)(struct vm_area_struct * area);
+	/**
+	 * @close: Called when the VMA is being removed from the MM.
+	 * Context: User context.  May sleep.  Caller holds mmap_lock.
+	 */
 	void (*close)(struct vm_area_struct * area);
 	/* Called any time before splitting to check if it's allowed */
 	int (*may_split)(struct vm_area_struct *area, unsigned long addr);
-- 
2.34.1.400.ga245620fadb-goog