Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This reduces the latency for RC ACKs when a PIO buffer is available.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Reset the retry counter when we get a good RDMA_READ_RESPONSE_MIDDLE
packet.  This fix will prevent the requester from reporting a retry
exceeded error too early.
Signed-off-by: NPatrick Marchand Latifi <patrick.latifi@qlogic.com>

This patch fixes a couple of minor problems with RNR NAK handling:
 - The insertion sort was causing extra delay when inserting ahead
   vs. behind an existing entry on the list.
 - A resend of a first packet of a message which is still not ready,
   needs another RNR NAK (i.e., it was suppressed when it shouldn't).
 - Also, the resend tasklet doesn't need to be woken up unless the
   ACK/NAK actually indicates progress has been made.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When an ACK is received, the QP is removed from the timeout list and
then if there are still pending send WQEs, the QP is put back on the
timeout list. It is possible that another post send has put the QP on
the timeout list thus, a check needs to be made before trying to do it
again or the list is corrupted.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch implements the IB_EVENT_QP_LAST_WQE_REACHED event which is
needed by ib_ipoib to destroy the QP when used in connected mode.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The code to post UD sends tried to process work requests at the time
ib_post_send() is called without using a WQE queue.  This was fine as
long as HW resources were available for sending a packet.  This patch
changes UD to be handled more like RC and UC and shares more code.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Now that it's June, it's about time to update
the copyright notices of files that have changed.
Signed-off-by: NJohn Gregor <john.gregor@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The IB specification ch. 9.9.3 table 58 says that a QP which isn't set
up for the operation should return a NAK invalid request.
Signed-off-by: NRobert Walsh <robert.walsh@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

A duplicate RDMA read request can fool the responder into NAKing a new
RDMA read request because the responder wasn't keeping track of
whether the queue of RDMA read requests had been sent at least once.
For example, requester sends 4 2K byte RDMA read requests, times out,
and resends the first, then sees the 4 responses, then sends a 5th
RDMA read or atomic operation.  The responder sees the 4 requests,
sends 4 responses, sees the resent 1st request, rewinds the queue,
then sees the 5th request but thinks the queue is full and that the
requester is invalidly sending a 5th new request.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

A RDMA read response or atomic response can ACK earlier sends and RDMA
writes.  In this case, the wrong work request pointer was being used
to store the read first response or atomic result.  Also, if a RDMA
read request is retried, the code to compute which request to resend
was incorrect.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

According to chapter 17.2.8.1.1, QPs start in the migrated state and
should send packets with the M bit set in the BTH.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix a problem where simple ACKs can be sent ahead of RDMA read
responses thus implicitly NAKing the RDMA read.
Signed-off-by: NRalph Campbell <ralph.cambpell@qlogic.com>
Signed-off-by: NRobert Walsh <robert.walsh@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix a missing unlock in ipath_rc_rcv_resp() and remove an extra unlock
from ipath_rc_rcv_error().
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This fixes a problem which causes too many RC timeouts and
retransmits.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch fixes the problem reported by Bernd Schubert <bs@q-leap.de>
with kernel debug options enabled:

    BUG: at kernel/lockdep.c:1860 trace_hardirqs_on()

This was caused by using spin_lock_irq()/spin_unlock_irq() from
interrupt context.  Fix all the places that might be called from
interrupts to use spin_lock_irqsave()/spin_unlock_irqrestore().
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix RDMA read response length checking for RDMA_READ_RESPONSE_ONLY to
allow a zero length response.  RDMA read responses which don't match
the expected length or occur in response to some other operation
should generate a completion queue error (see table 56, ch. 9.9.2.3 in
the IB spec).
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch fixes a number of bugs with updating the PSN for retries of
RC requests.
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When switching to the QP error state, the completion queue entries
(error or flush) were not being generated correctly.
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This patch adds support for multiple RDMA reads and atomics to be sent
before an ACK is required to be seen by the requester.
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

struct ib_wc currently only includes the local QP number: this matches
the IB spec, but seems mostly useless. The following patch replaces
this with the pointer to qp itself, and updates all low level drivers
and all users.

This has the following advantages:
- Ability to get a per-qp context through wc->qp->qp_context
- Existing drivers already have the qp pointer ready in poll cq, so
  this change actually saves a tiny bit (extra memory read) on data path
  (for ehca it would actually be expensive to find the QP pointer when
  polling a CQ, but ehca does not support SRQ so we can leave wc->qp as
  NULL for ehca)
- Users that need the QP number can still get it through wc->qp->qp_num

Use case:

In IPoIB connected mode code, I have a common CQ shared by multiple
QPs.  To track connection usage, I need a way to get at some per-QP
context upon the completion, and I would like to avoid allocating
context object per work request just to stick a QP pointer into it.
With this code, I can just use wc->qp->qp_context.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The PSN used to generate the request following a RDMA read was
incorrect and some state booking wasn't maintained correctly.  This
patch fixes that.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>

If the receiver goes into the error state, we need to flush the
posted receive WQEs.
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This is required for IB conformance (spec ch. 9.6.1.5).
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The sender requests an ACK every 1/2 MB to avoid retransmit timeouts that
were causing MVAPICH mod_bw to fail after a predictable number of sends.
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

A lot of ipath layer code was only called in one place. Now that the
ipath_core and ib_ipath drivers are merged, it's more sensible to simply
inline the simple stuff that the layer code was doing.
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Remove ips namespace from infinipath drivers.  This renames ips_common.h to
ipath_common.h.  Definitions, data structures, etc.  that were not used by
kernel modules have moved to user-only headers.  All names including ips have
been renamed to ipath.  Some names have had an ipath prefix added.
Signed-off-by: NChristian Bell <christian.bell@qlogic.com>
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch separates QP state used for sending and receiving RC packets so the
processing in the receive interrupt handler can be done mostly without locks
being held.  ACK packets are now sent without requiring synchronization with
the send tasklet.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NBryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Per Andrew's request.
Signed-off-by: NBryan O'Sullivan <bos@pathscale.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This is an implementation of the Infiniband RC ("reliable connection")
protocol.
Signed-off-by: NBryan O'Sullivan <bos@pathscale.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>