Hi-- On 9/8/25 4:10 AM, Lorenzo Stoakes wrote: > We have introduced the mmap_complete() and mmap_abort() callbacks, which > work in conjunction with mmap_prepare(), so describe what they used for. > > We update both the VFS documentation and the porting guide. > > Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> > --- > Documentation/filesystems/porting.rst | 9 +++++++ > Documentation/filesystems/vfs.rst | 35 +++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+) > > diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst > index 486a91633474..172d36a13e13 100644 > --- a/Documentation/filesystems/vfs.rst > +++ b/Documentation/filesystems/vfs.rst > @@ -1236,6 +1240,37 @@ otherwise noted. > file-backed memory mapping, most notably establishing relevant > private state and VMA callbacks. > > +``mmap_complete`` > + If mmap_prepare is provided, will be invoked after the mapping is fully s/mmap_prepare/mmap_complete/ ?? > + established, with the mmap and VMA write locks held. > + > + It is useful for prepopulating VMAs before they may be accessed by > + users. > + > + The hook MUST NOT release either the VMA or mmap write locks. This is You could also do **bold** above: The hook **MUST NOT** release ... > + asserted by the mmap logic. > + > + If an error is returned by the hook, the VMA is unmapped and the > + mmap() operation fails with that error. > + > + It is not valid to specify this hook if mmap_prepare is not also > + specified, doing so will result in an error upon mapping. -- ~Randy
