The function __flush_qp() always calls the ULP's CQ completion handler
functions even if the CQ was not armed.  This can crash the system if
the function pointer is NULL. The iSER ULP behaves this way: no
completion handler and never arm the CQ for notification.  So now we
track whether the CQ is armed at flush time and only call the
completion handlers if their CQs were armed.

Also, if the RCQ and SCQ are the same CQ, the completion handler is
getting called twice.  It should only be called once after all SQ and
RQ WRs are flushed from the QP.  So rearrange the logic to fix this.
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Move QP to TERMINATE instead to allow the peer to get the TERM
message. This bug wasn't detectable until newer FW that moves
connections out of RDMA mode as soon as an error is detected.

QP can exit RTS before the last AE arrives.  This was introduced by
changes in the FW to kick connections out of RDMA mode as soon as an
error is detected.  A side effect of this is that the driver can move
the QP out of RTS before the AE causing the connection to get kicked
out of RDMA mode is processed.  Fix for this is to always post async
errors even if the QP is out of RTS.
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NVipul Pandya <vipul@chelsio.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Log AEs even if the QP isn't in RTS.  It is useful information.
Signed-off-by: NVipul Pandya <vipul@chelsio.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Use GFP_ATOMIC in _insert_handle() if ints are disabled.

Don't panic if we get an abort with no endpoint found.  Just log a
warning.
Signed-off-by: NVipul Pandya <vipul@chelsio.com>
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Commit 01e7da6b ("RDMA/cxgb4: Make sure flush CQ entries are
collected on connection close") introduced a potential problem where a
CQ's comp_handler can get called simultaneously from different places
in the iw_cxgb4 driver.  This does not comply with
Documentation/infiniband/core_locking.txt, which states that at a
given point of time, there should be only one callback per CQ should
be active.

This problem was reported by Parav Pandit <Parav.Pandit@Emulex.Com>.
Based on discussion between Parav Pandit and Steve Wise, this patch
fixes the above problem by serializing the calls to a CQ's
comp_handler using a spin_lock.
Reported-by: NParav Pandit <Parav.Pandit@Emulex.Com>
Signed-off-by: NKumar Sanghvi <kumaras@chelsio.com>
Acked-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

T4 FW sends up CPL_RDMA_TERMINATE to indicate a peer TERM.  This
triggers the QP moving to TERMINATE state.
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add an RDMA/iWARP driver for Chelsio T4 Ethernet adapters.
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>