[PATCH v3 0/9] fuse: DAX device based extent maps (famfs)

[Miklos Szeredi <mszeredi@redhat.com>]

This is the FUSIfication of the famfs-fuse patchset.

 - extent maps are assigned to a backing ID

 - 64 bit backing ID's managed by server

 - maps can be linear or cyclic (striped)

 - API supports nesting, but not implemented yet (i.e. multiple striped
   extents per inode, a-la famfs)

libfuse/famfs trees for testing:

 https://github.com/szmi/libfuse.git#extent-map-v3
 https://github.com/szmi/famfs.git#extent-map-v3

This patchset:

 git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git#extent-map-v3

Passes famfs smoke test on emulated dax device.

Comments are welcome.

Thanks,
Miklos

---
Changes since v2:

 - add a trivial prep patch modifying drivers/dax/super.c
 - reserve zero value for 64 bit backing ID (Amir)
 - add Originally-by: tag to acknowledge John's work 
 - more fixes and cleanups (Amir, Sashiko)

Changes since v1:

 - moved 3 prep patches to fuse.git#for-next
 - introduce FUSE_PASSTHROUGH_V2 (Amir)
 - lots of small fixes and cleanups (Amir, Sashiko)


John Groves (1):
  dax: replace exported dax_dev_get() with non-allocating dax_dev_find()

Miklos Szeredi (8):
  dax: use READ_ONCE() in dax_holder()
  fuse: add helpers for EIO return value with kernel message
  fuse: support 64 bit, server allocated backing ID
  fuse: support opening 64 bit backing ID
  fuse: add support for opening dax device as backing
  fuse: add extent map data structure
  fuse: add extent map I/O support
  fuse: add support for striped backing

 drivers/dax/super.c       |  40 ++++-
 fs/fuse/Makefile          |   2 +-
 fs/fuse/backing.c         | 305 +++++++++++++++++++++++++++++-------
 fs/fuse/dev.c             |  24 +++
 fs/fuse/dev.h             |   3 +
 fs/fuse/dir.c             |   3 +-
 fs/fuse/ext_map.c         | 316 ++++++++++++++++++++++++++++++++++++++
 fs/fuse/file.c            |  18 ++-
 fs/fuse/fuse_i.h          |  78 ++++++++--
 fs/fuse/inode.c           |  26 +++-
 fs/fuse/iomode.c          | 116 ++++++++------
 fs/fuse/notify.c          |  75 +++++++++
 fs/fuse/passthrough.c     |  63 ++++----
 include/linux/dax.h       |   6 +-
 include/uapi/linux/fuse.h |  53 ++++++-
 15 files changed, 965 insertions(+), 163 deletions(-)
 create mode 100644 fs/fuse/ext_map.c

-- 
2.54.0