futher decouple DAX from block devices

[Dan Williams]

[ add sfr ]

On Sun, Oct 17, 2021 at 9:41 PM Christoph Hellwig <hch at lst.de> wrote:
>
> Hi Dan,
>
> this series cleans up and simplifies the association between DAX and block
> devices in preparation of allowing to mount file systems directly on DAX
> devices without a detour through block devices.

So I notice that this is based on linux-next while libnvdimm-for-next
is based on v5.15-rc4. Since I'm not Andrew I went ahead and rebased
these onto v5.15-rc4, tested that, and then merged with linux-next to
resolve the conflicts and tested again.

My merge resolution is here [1]. Christoph, please have a look. The
rebase and the merge result are both passing my test and I'm now going
to review the individual patches. However, while I do that and collect
acks from DM and EROFS folks, I want to give Stephen a heads up that
this is coming. Primarily I want to see if someone sees a better
strategy to merge this, please let me know, but if not I plan to walk
Stephen and Linus through the resolution.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm.git/commit/?id=c3894cf6eb8f


>
> Diffstat:
>  drivers/dax/Kconfig          |    4
>  drivers/dax/bus.c            |    2
>  drivers/dax/super.c          |  220 +++++--------------------------------------
>  drivers/md/dm-linear.c       |   51 +++------
>  drivers/md/dm-log-writes.c   |   44 +++-----
>  drivers/md/dm-stripe.c       |   65 +++---------
>  drivers/md/dm-table.c        |   22 ++--
>  drivers/md/dm-writecache.c   |    2
>  drivers/md/dm.c              |   29 -----
>  drivers/md/dm.h              |    4
>  drivers/nvdimm/Kconfig       |    2
>  drivers/nvdimm/pmem.c        |    9 -
>  drivers/s390/block/Kconfig   |    2
>  drivers/s390/block/dcssblk.c |   12 +-
>  fs/dax.c                     |   13 ++
>  fs/erofs/super.c             |   11 +-
>  fs/ext2/super.c              |    6 -
>  fs/ext4/super.c              |    9 +
>  fs/fuse/Kconfig              |    2
>  fs/fuse/virtio_fs.c          |    2
>  fs/xfs/xfs_super.c           |   54 +++++-----
>  include/linux/dax.h          |   30 ++---
>  22 files changed, 185 insertions(+), 410 deletions(-)