Re: [PATCH v12 1/7] dax: Introduce holder for dax_device

[Dan Williams]

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.