[PATCH v6 0/7] implement -ENOSPC handling in cephfs

[Jeff Layton <jlayton@redhat.com>]

v6: reset barrier to current epoch when receiving map with full pool or
    at quota condition. Show epoch barrier in debugfs. Don't take osd->lock
    unnecessarily. Remove req->r_replay_version. Other cleanups and
    fixes suggested by Ilya.

v5: rebase onto ACK vs. commit changes

v4: eliminate map_cb and just call ceph_osdc_abort_on_full directly
Revert earlier patch flagging individual pages with error on writeback
failure. Add mechanism to force synchronous writes when writes start
failing, and reallowing async writes when they succeed.

v3: track "abort_on_full" behavior with a new bool in osd request
instead of a protocol flag. Remove some extraneous arguments from
various functions. Don't export have_pool_full, call it from the
abort_on_full callback instead.

v2: teach libcephfs how to hold on to requests until the right map
epoch appears, instead of delaying cap handling in the cephfs layer.

Ok, with this set, I think we have proper -ENOSPC handling for all
different write types (direct, sync, async buffered, etc...). -ENOSPC
conditions.

This patchset is an updated version of the patch series originally
done by John Spray and posted here:

    http://www.spinics.net/lists/ceph-devel/msg21257.html

The only real change from the last posting was to rebase it on top
of Ilya's changes to remove the ack vs. commit behavior. That rebase
was fairly simple and turns out to simplify the changes somewhat.

In the last series Zheng also mentioned removing the other SetPageError
sites in fs/ceph. That may make sense, but I've left that out for now,
as I'd like to look over PG_error handling in the kernel at large.

Jeff Layton (7):
  libceph: remove req->r_replay_version
  libceph: allow requests to return immediately on full conditions if
    caller wishes
  libceph: abort already submitted but abortable requests when map or
    pool goes full
  libceph: add an epoch_barrier field to struct ceph_osd_client
  ceph: handle epoch barriers in cap messages
  Revert "ceph: SetPageError() for writeback pages if writepages fails"
  ceph: when seeing write errors on an inode, switch to sync writes

 fs/ceph/addr.c                  | 10 +++--
 fs/ceph/caps.c                  | 17 ++++++--
 fs/ceph/file.c                  | 32 ++++++++------
 fs/ceph/mds_client.c            | 20 +++++++++
 fs/ceph/mds_client.h            |  7 +++-
 fs/ceph/super.h                 | 26 ++++++++++++
 include/linux/ceph/osd_client.h |  4 +-
 net/ceph/debugfs.c              |  7 ++--
 net/ceph/osd_client.c           | 92 ++++++++++++++++++++++++++++++++++++-----
 9 files changed, 177 insertions(+), 38 deletions(-)

-- 
2.9.3