* pnfs_generic:
  NFSv4.1/pNFS: Cleanup constify struct pnfs_layout_range arguments
  NFSv4.1/pnfs: Cleanup copying of pnfs_layout_range structures
  NFSv4.1/pNFS: Cleanup pnfs_mark_matching_lsegs_invalid()
  NFSv4.1/pNFS: Fix a race in initiate_file_draining()
  NFSv4.1/pNFS: pnfs_error_mark_layout_for_return() must always return layout
  NFSv4.1/pNFS: pnfs_mark_matching_lsegs_return() should set the iomode
  NFSv4.1/pNFS: Use nfs4_stateid_copy for copying stateids
  NFSv4.1/pNFS: Don't pass stateids by value to pnfs_send_layoutreturn()
  NFS: Relax requirements in nfs_flush_incompatible
  NFSv4.1/pNFS: Don't queue up a new commit if the layout segment is invalid
  NFS: Allow multiple commit requests in flight per file
  NFS/pNFS: Fix up pNFS write reschedule layering violations and bugs
  NFSv4: List stateid information in the callback tracepoints
  NFSv4.1/pNFS: Don't return NFS4ERR_DELAY unnecessarily in CB_LAYOUTRECALL
  NFSv4.1/pNFS: Ensure we enforce RFC5661 Section 12.5.5.2.1
  pNFS: If we have to delay the layout callback, mark the layout for return
  NFSv4.1/pNFS: Add a helper to mark the layout as returned
  pNFS: Ensure nfs4_layoutget_prepare returns the correct error

Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Make it more obvious what we're returning...
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Peng Tao points out that the call to pnfs_mark_matching_lsegs_return()
could race with pnfs_put_lseg(), in which case the layout segment is
cleared, but no layoutreturn will be sent.
Fix is to replace the call to pnfs_mark_matching_lsegs_invalid().
Reported-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Fix a bug whereby if all the layout segments could be immediately freed,
the call to pnfs_error_mark_layout_for_return() would never result in
a layoutreturn.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If pnfs_mark_matching_lsegs_return() needs to mark a layout segment for
return, then it must also set the return iomode.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

A stateid is a structure, pass it as a pointer.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If two processes share the same credentials and NFSv4 open stateid, then
allow them both to dirty the same page, even if their nfs_open_context
differs.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the layout segment is invalid, then we should not be adding more
write requests to the commit list. Instead, those writes should be
replayed after requesting a new layout.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Allow synchronous RPC calls to wait for pending RPC calls to finish,
but also allow asynchronous ones to just fire off another commit.

With this patch, the xfstests generic/074 test completes in 226s
instead of 242s
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The flexfiles layout in particular, seems to want to poke around in the
O_DIRECT flags when retransmitting.
This patch sets up an interface to allow it to call back into O_DIRECT
to handle retransmission correctly. It also fixes a potential bug whereby
we could change the behaviour of O_DIRECT if an error is already pending.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

* flexfiles:
  pNFS/flexfiles: Ensure we record layoutstats even if RPC is terminated early
  pNFS: Add flag to track if we've called nfs4_ff_layout_stat_io_start_read/write
  pNFS/flexfiles: Fix a statistics gathering imbalance
  pNFS/flexfiles: Don't mark the entire layout as failed, when returning it
  pNFS/flexfiles: Don't prevent flexfiles client from retrying LAYOUTGET
  pnfs/flexfiles: count io stat in rpc_count_stats callback
  pnfs/flexfiles: do not mark delay-like status as DS failure
  NFS41: map NFS4ERR_LAYOUTUNAVAILABLE to ENODATA
  nfs: only remove page from mapping if launder_page fails
  nfs: handle request add failure properly
  nfs: centralize pgio error cleanup
  nfs: clean up rest of reqs when failing to add one
  NFS41: pop some layoutget errors to application
  pNFS/flexfiles: Support server-supplied layoutstats sampling period

NFS: NFSoRDMA Client Side Changes

These patches mostly fix send queue ordering issues inside the NFSoRDMA
client, but there are also two patches from Dan Carpenter fixing up smatch
warnings.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

* tag 'nfs-rdma-4.5' of git://git.linux-nfs.org/projects/anna/nfs-rdma:
  xprtrdma: Revert commit e7104a2a ('xprtrdma: Cap req_cqinit').
  xprtrdma: Invalidate in the RPC reply handler
  xprtrdma: Add ro_unmap_sync method for all-physical registration
  xprtrdma: Add ro_unmap_sync method for FMR
  xprtrdma: Add ro_unmap_sync method for FRWR
  xprtrdma: Introduce ro_unmap_sync method
  xprtrdma: Move struct ib_send_wr off the stack
  xprtrdma: Disable RPC/RDMA backchannel debugging messages
  xprtrdma: xprt_rdma_free() must not release backchannel reqs
  xprtrdma: Fix additional uses of spin_lock_irqsave(rb_lock)
  xprtrdma: checking for NULL instead of IS_ERR()
  xprtrdma: clean up some curly braces

The stateid is extremely valuable when debugging.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the client is promising to return the layout ASAP, then there is no
need to return DELAY and have the server retry. Instead default to the
normal procedure described in RFC5661.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The RFC requires us to check if the server is recalling a stateid that we
haven't yet received. If so, tell it to wait.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the client needs to delay the layout callback, then speed up the recall
process by marking the remaining layout segments to be actively returned
by the client.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This ensures that we don't reuse the stateid if a layout return or
implied layout return means that we've returned all layout segments
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we're unable to perform the layoutget due to an invalid open stateid
or a bulk recall, ensure that we return the error so that the caller
can decide on an appropriate action.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Currently, we will only record the layoutstats correctly if the
RPC call successfully obtains a slot. If we exit before that
happens, then we may find ourselves starting the busy timer through
the call in ff_layout_(read|write)_prepare_layoutstats, but never stopping it.

The same thing happens if we're doing DA-DS.

The fix is to ensure that we catch these cases in the rpc_release()
callback.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

When we replay a failed read, write or commit to the dataserver, we
need to ensure that we call ff_layout_read_prepare_v3(),
ff_layout_write_prepare_v3 or ff_layout_commit_prepare_v3() so that we
reset the statistics.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

In pNFS/flexfiles, we want to return the layout without necessarily marking
it as having completely failed. We therefore move the call to
pnfs_layout_io_set_failed() out of pnfs_error_mark_layout_for_return(),
and then ensura that pNFS/files layout calls it separately.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Fix a bug in which flexfiles clients are falling back to I/O through the
MDS even when the FF_FLAGS_NO_IO_THRU_MDS flag is set.

The flexfiles client will always report errors through the LAYOUTRETURN
and/or LAYOUTERROR mechanisms, so it should normally be safe for it
to retry the LAYOUTGET until it fails or succeeds.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If client ever restarts IO due to some errors, we'll endup
mis-counting IO stats if we do the counting in .rpc_done
callback. Move it to .rpc_count_stats callback that is only
called when releasing RPC.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We just need to delay and retry in these cases.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Instead of mapping it to EIO that is a fatal error and
fails application. We'll go inband after getting
NFS4ERR_LAYOUTUNAVAILABLE.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Instead of dropping pages when write fails, only do it when
we get fatal failure in launder_page write back.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

When we fail to queue a read page to IO descriptor,
we need to clean it up otherwise it is hanging around
preventing nfs module from being removed.

When we fail to queue a write page to IO descriptor,
we need to clean it up and also save the failure status
to open context. Then at file close, we can try to write
pages back again and drop the page if it fails to writeback
in .launder_page, which will be done in the next patch.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

In case we fail during setting things up for read/write IO, set
pg_error in IO descriptor and do the cleanup in nfs_pageio_add_request,
where we clean up all pages that are still hanging around on the IO
descriptor.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we fail to set up things before sending anything over wire,
we need to clean up the reqs that are still attached to the
IO descriptor.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

For ERESTARTSYS/EIO/EROFS/ENOSPC/E2BIG in layoutget, we
should just bail out instead of hiding the error and
retrying inband IO.

Change all the call sites to pop the error all the way up.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Some servers want to be able to control the frequency with which clients
report layoutstats, for instance, in order to monitor QoS for a particular
file or set of file. In order to support this, the flexfiles layout allows
the server to pass this info as a hint in the layout payload.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

xs_reclassify_socket4() and friends used to be called directly.
xs_reclassify_socket() is called instead nowadays.

The xs_reclassify_socketX() helper functions are empty when
CONFIG_DEBUG_LOCK_ALLOC is not defined.  Drop them since they have no
callers.

Note that AF_LOCAL still calls xs_reclassify_socketu() directly but is
easily converted to generic xs_reclassify_socket().
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Allow LAYOUTRETURN and DELEGRETURN to use machine credentials if the
server supports it. Add request for OPEN_DOWNGRADE as the close path
also uses that.
Signed-off-by: NAndrew Elble <aweits@rit.edu>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This patch fixes the checkpatch.pl error to nfs4sysctl.c:

ERROR: do not initialise statics to 0
Signed-off-by: NWei Tang <tangwei@cmss.chinamobile.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Instead of displaying a layout segment pointer in these tracepoints,
let's use the layout stateid, now that Olga gave us a set of tools for
displaying them.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>