On Sun, Apr 10, 2022 at 9:09 AM Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx> wrote: > > To easily track filesystem from a pmem device, we introduce a holder for > dax_device structure, and also its operation. This holder is used to > remember who is using this dax_device: > - When it is the backend of a filesystem, the holder will be the > instance of this filesystem. > - When this pmem device is one of the targets in a mapped device, the > holder will be this mapped device. In this case, the mapped device > has its own dax_device and it will follow the first rule. So that we > can finally track to the filesystem we needed. > > The holder and holder_ops will be set when filesystem is being mounted, > or an target device is being activated. > Looks good to me: Reviewed-by: Dan Williams <dan.j.wiliams@xxxxxxxxx> I am assuming this will be staged in a common DAX branch, but holler now if this should go through the XFS tree.