mm/vma: document possible vma->vm_refcnt values and reference comment

The possible vma->vm_refcnt values are confusing and vague, explain in
detail what these can be in a comment describing the vma->vm_refcnt field
and reference this comment in various places that read/write this field.

No functional change intended.

[akpm@linux-foundation.org: fix typo, per Suren]
Link: https://lkml.kernel.org/r/d462e7678c6cc7461f94e5b26c776547d80a67e8.1769198904.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Waiman Long <longman@redhat.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Lorenzo Stoakes 2026-01-23 20:12:12 +00:00 • committed by Andrew Morton
commit ef4c0cea1e
3 changed files with 53 additions and 2 deletions