[PATCH v4 00/21] NFS/RDMA client patches for 3.17

[Chuck Lever <chuck.lever@oracle.com>]

The main purpose of this series is to address connection drop
recovery issues by fixing FRMR re-use to make it less likely the
client will deadlock due to a memory management operation error.
Some clean-ups and other fixes are present as well.

Anna, v4 of this series should be ready for merging.

See topic branch nfs-rdma-for-3.17 in

git://git.linux-nfs.org/projects/cel/cel-2.6.git

I tested with NFSv3 and NFSv4 on all three supported memory
registration modes. Used cthon04, iozone, and dbench with both
Solaris and Linux NFS/RDMA servers. Used xfstests with Linux.

v4:

- Rebased on v3.16-rc6

- Add Tested-by: from Shirley Ma and Devesh Sharma


v3:
Only two substantive changes:

- Patch 08/21 now uses generic IB helpers for managing FRMR
 rkeys

- Add Tested-by: from Steve Wise


v2:
Many patches from v1 have been written or replaced.

The MW ref counting approach in v1 is abandoned. Instead, I've
eliminated signaling FAST_REG_MR and LOCAL_INV, and added
appropriate recovery mechanisms after a transport reconnect that
should prevent rkey dis-synchrony entirely.

A couple of optimizations have been added, including:

- Allocating each MW separately rather than carving each out of a
 large piece of contiguous memory

- Now that the receive CQ upcall handler dequeues a bundle of CQEs
 at once, fire off the reply handler tasklet just once per upcall
 to reduce context switches and how often hard IRQs are disabled

---

Chuck Lever (21):
      xprtrdma: Fix panic in rpcrdma_register_frmr_external()
      xprtrdma: Protect ia->ri_id when unmapping/invalidating MRs
      xprtrdma: Limit data payload size for ALLPHYSICAL
      xprtrdma: Update rkeys after transport reconnect
      xprtrdma: On disconnect, don't ignore pending CQEs
      xprtrdma: Don't invalidate FRMRs if registration fails
      xprtrdma: Unclutter struct rpcrdma_mr_seg
      xprtrdma: Back off rkey when FAST_REG_MR fails
      xprtrdma: Chain together all MWs in same buffer pool
      xprtrdma: Properly handle exhaustion of the rb_mws list
      xprtrdma: Reset FRMRs when FAST_REG_MR is flushed by a disconnect
      xprtrdma: Reset FRMRs after a flushed LOCAL_INV Work Request
      xprtrdma: Don't post a LOCAL_INV in rpcrdma_register_frmr_external()
      xprtrdma: Disable completions for FAST_REG_MR Work Requests
      xprtrdma: Disable completions for LOCAL_INV Work Requests
      xprtrdma: Rename frmr_wr
      xprtrdma: Allocate each struct rpcrdma_mw separately
      xprtrdma: Schedule reply tasklet once per upcall
      xprtrdma: Make rpcrdma_ep_disconnect() return void
      xprtrdma: Remove RPCRDMA_PERSISTENT_REGISTRATION macro
      xprtrdma: Handle additional connection events


 include/linux/sunrpc/xprtrdma.h |    2 
 include/rdma/ib_verbs.h         |   11 +
 net/sunrpc/xprtrdma/rpc_rdma.c  |   83 ++--
 net/sunrpc/xprtrdma/transport.c |   17 +
 net/sunrpc/xprtrdma/verbs.c     |  744 ++++++++++++++++++++++++++-------------
 net/sunrpc/xprtrdma/xprt_rdma.h |   61 +++
 6 files changed, 615 insertions(+), 303 deletions(-)

--
Chuck Lever