From: Suren Baghdasaryan <surenb@xxxxxxxxxx> Subject: mm: document locking restrictions for vm_operations_struct::close Add comments for vm_operations_struct::close documenting locking requirements for this callback and its callers. Link: https://lkml.kernel.org/r/20211209191325.3069345-2-surenb@xxxxxxxxxx Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Christian Brauner <christian@xxxxxxxxxx> Cc: Christian Brauner <christian.brauner@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Florian Weimer <fweimer@xxxxxxxxxx> Cc: Jan Engelhardt <jengelh@xxxxxxx> Cc: Jann Horn <jannh@xxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxxx> Cc: Roman Gushchin <guro@xxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: Tim Murray <timmurray@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mm.h | 4 ++++ 1 file changed, 4 insertions(+) --- a/include/linux/mm.h~mm-document-locking-restrictions-for-vm_operations_struct-close +++ a/include/linux/mm.h @@ -532,6 +532,10 @@ 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); _
