Re: [PATCH 03/15] mm: document vm_operations_struct->open the same as close()

Suren Baghdasaryan
2026-03-16T00:43:58Z

On Thu, Mar 12, 2026 at 1:27 PM Lorenzo Stoakes (Oracle) <ljs@kernel.org> wrote:
>
> Describe when the operation is invoked and the context in which it is
> invoked, matching the description already added for vm_op->close().
>
> While we're here, update all outdated references to an 'area' field for
> VMAs to the more consistent 'vma'.
>
> Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
> ---
> include/linux/mm.h | 15 ++++++++++-----
> 1 file changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index cc5960a84382..12a0b4c63736 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -748,15 +748,20 @@ struct vm_uffd_ops;
> * to the functions called when a no-page or a wp-page exception occurs.
> */
> struct vm_operations_struct {
> - void (*open)(struct vm_area_struct * area);
> + /**
> + * @open: Called when a VMA is remapped or split. Not called upon first
> + * mapping a VMA.

It's also called from dup_mmap() which is part of forking.

> + * Context: User context. May sleep. Caller holds mmap_lock.
> + */
> + void (*open)(struct vm_area_struct *vma);
> /**
> * @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);
> + void (*close)(struct vm_area_struct *vma);
> /* Called any time before splitting to check if it's allowed */
> - int (*may_split)(struct vm_area_struct *area, unsigned long addr);
> - int (*mremap)(struct vm_area_struct *area);
> + int (*may_split)(struct vm_area_struct *vma, unsigned long addr);
> + int (*mremap)(struct vm_area_struct *vma);
> /*
> * Called by mprotect() to make driver-specific permission
> * checks before mprotect() is finalised. The VMA must not
> @@ -768,7 +773,7 @@ struct vm_operations_struct {
> vm_fault_t (*huge_fault)(struct vm_fault *vmf, unsigned int order);
> vm_fault_t (*map_pages)(struct vm_fault *vmf,
> pgoff_t start_pgoff, pgoff_t end_pgoff);
> - unsigned long (*pagesize)(struct vm_area_struct * area);
> + unsigned long (*pagesize)(struct vm_area_struct *vma);
>
> /* notification that a previously read-only page is about to become
> * writable, if an error is returned it will cause a SIGBUS */
> --
> 2.53.0
>