Take isert_conn pointer from cm_id->qp->qp_context. This
will allow us to know that the cm_id context is always
the network portal. This will make the cm_id event check
(connection or network portal) more reliable.

In order to avoid a NULL dereference in cma_id->qp->qp_context
we destroy the qp after we destroy the cm_id (and make the
dereference safe). session stablishment/teardown sequences
can happen in parallel, we should take into account that
connected_handler might race with connection teardown flow.

Also, protect isert_conn->conn_device->active_qps decrement
within the error patch during QP creation failure and the
normal teardown path in isert_connect_release().

Squashed:

iser-target: Decrement completion context active_qps in error flow
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There is no point in accepting a new CM request only
when we are completely done with the last iscsi login.
Instead we accept immediately, this will also cause the
CM connection to reach connected state and the initiator
is allowed to send the first login. We mark that we got
the initial login and let iscsi layer pick it up when it
gets there.

This reduces the parallel login sequence by a factor of
more then 4 (and more for multi-login) and also prevents
the initiator (who does all logins in parallel) from
giving up on login timeout expiration.

In order to support multiple login requests sequence (CHAP)
we call isert_rx_login_req from isert_rx_completion insead
of letting isert_get_login_rx call it.

Squashed:

iser-target: Use kref_get_unless_zero in connected_handler
iser-target: Acquire conn_mutex when changing connection state
iser-target: Reject connect request in failure path
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

ISER_CONN_UP state is not sufficient to know if
we should wait for completion of flush errors and
disconnected_handler event.

Instead, split it to 2 states:
- ISER_CONN_UP: Got to CM connected phase, This state
indicates that we need to wait for a CM disconnect
event before going to teardown.

- ISER_CONN_FULL_FEATURE: Got to full feature phase
after we posted login response, This state indicates
that we posted recv buffers and we need to wait for
flush completions before going to teardown.

Also avoid deffering disconnected handler to a work,
and handle it within disconnected handler.
More work here is needed to handle DEVICE_REMOVAL event
correctly (cleanup all resources).

Squashed:

iser-target: Don't deffer disconnected handler to a work
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Since commit 0fc4ea70 ("Target/iser: Don't put isert_conn inside
disconnected handler") we put the conn kref in isert_wait_conn, so we
need .wait_conn to be invoked also in the error path.

Introduce call to isert_conn_terminate (called under lock)
which transitions the connection state to TERMINATING and calls
rdma_disconnect. If the state is already teminating, just bail
out back (temination started).

Also, make sure to destroy the connection when getting a connect
error event if didn't get to connected (state UP). Same for the
handling of REJECTED and UNREACHABLE cma events.

Squashed:

iscsi-target: Add call to wait_conn in establishment error flow
Reported-by: NSlava Shwartsman <valyushash@gmail.com>
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

isert has an issue of trying to create a CQ with more CQEs than are
supported by the hardware, that currently results in failures during
isert_device creation during first session login.

This is the isert version of the patch that Minh Tran submitted for
iser, and is simple a workaround required to function with existing
ocrdma hardware.
Signed-off-by: NChris Moore <chris.moore@emulex.com>
Reviewied-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In this case the cm_id->context is the isert_np, and the cm_id->qp
is NULL, so use that to distinct the cases.

Since we don't expect any other events on this cm_id we can
just return -1 for explicit termination of the cm_id by the
cma layer.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds a max_send_sge=2 minimum in isert_conn_setup_qp()
to ensure outgoing control PDU responses with tx_desc->num_sge=2
are able to function correctly.

This addresses a bug with RDMA hardware using dev_attr.max_sge=3,
that in the original code with the ConnectX-2 work-around would
result in isert_conn->max_sge=1 being negotiated.

Originally reported by Chris with ocrdma driver.
Reported-by: NChris Moore <Chris.Moore@emulex.com>
Tested-by: NChris Moore <Chris.Moore@emulex.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Cc: <stable@vger.kernel.org> # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Expose more signature setting parameters. We modify the signature API
to allow usage of some new execution parameters relevant to data
integrity feature.

This patch modifies ib_sig_domain structure by:

- Deprecate DIF type in signature API (operation will
  be determined by the parameters alone, no DIF type awareness)
- Add APPTAG check bitmask (for input domain)
- Add REFTAG remap (increment) flag for each domain
- Add APPTAG/REFTAG escape options for each domain

The mlx5 driver is modified to follow the new parameters in HW
signature setup.

At the moment the callers (iser/isert) hard-code new parameters (by
DIF type). In the future, callers will retrieve them from the scsi
command structure.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

Later there will be more parameters to set, so we want to do it in a
centralized place.

This patch does not change any functionality.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

This patch explicitly disables TX completion interrupt coalescing logic
in isert_put_response() and isert_put_datain() that was originally added
as an efficiency optimization in commit 95b60f07.

It has been reported that this change can trigger ABORT_TASK timeouts
under certain small block workloads, where disabling coalescing was
required for stability.  According to Sagi, this doesn't impact
overall performance, so go ahead and disable it for now.
Reported-by: NMoussa Ba <moussaba@micron.com>
Reported-by: NSagi Grimberg <sagig@dev.mellanox.co.il>
Cc: <stable@vger.kernel.org> # 3.13+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Unused return value from down_interruptible
Reported-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The iser target is the RDMA requester and the iser initiator is the
RDMA responder. In order to determine the max inflight RDMA READ requests
to set on the QP (initiator_depth), it should take the min between the
initiator published initiator_depth and the max inflight rdma read
requests its local HCA support (max_qp_init_rd_atom).

The target will never handle incoming RDMA READ requests so no need to
set responder_resources.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

rdma_disconnect may be called in 2 code flows:
- isert_wait_conn: disconnect initiated be the target
- disconnected_handler: disconnect invoked by the initiator

In case isert_conn->disconnect is true then rdma_disconnect
was called in disconnected handler, no need to call it again
from isert_wait_conn.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

disconnected_handler is invoked on several CM events (such
as DISCONNECTED, DEVICE_REMOVAL, TIMEWAIT_EXIT...). Since
multiple  events can occur while before isert_free_conn is
invoked, we might put all isert_conn references and free
the connection too early.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case the connection didn't reach connected state, disconnected
handler will never be invoked thus the second kref_put on
isert_conn will be missing.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case the transport is iser we should not include the
iscsi target info in the sendtargets text response pdu.
This causes sendtargets response to include the target
info twice.

Modify iscsit_build_sendtargets_response to filter
transport types that don't match.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Reported-by: NSlava Shwartsman <valyushash@gmail.com>
Cc: stable@vger.kernel.org # 3.11+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case the discovery session is carried over iser, we can't
access the assumed network portal since the default portal is
used. In this case we don't really need to allocate the fastreg
pool, just prepare to the text pdu that will follow.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Reported-by: NAlex Tabachnik <alext@mellanox.com>
Cc: stable@vger.kernel.org # 3.15+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses a bug where an early exception for SCSI WRITE
with ImmediateData=Yes was missing the target_put_sess_cmd() call
to drop the extra se_cmd->cmd_kref reference obtained during the
normal iscsit_setup_scsi_cmd() codepath execution.

This bug was manifesting itself during session shutdown within
isert_cq_rx_comp_err() where target_wait_for_sess_cmds() would
end up waiting indefinately for the last se_cmd->cmd_kref put to
occur for the failed SCSI WRITE + ImmediateData descriptors.

This fix follows what traditional iscsi-target code already does
for the same failure case within iscsit_get_immediate_data().
Reported-by: NSagi Grimberg <sagig@dev.mellanox.co.il>
Cc: Sagi Grimberg <sagig@dev.mellanox.co.il>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case user chose to set T10-PI enable on the target while
the IB device does not support it, gracefully reject the request.
Reported-by: NSlava Shwartsman <valyushash@gmail.com>
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.15+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

disconnected_handler works are scheduled on system_wq.
When attempting to unload, first make sure all works
have cleaned up.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There are 4 RDMA_CM events that all basically mean that
the user should teardown the IB connection:
- DISCONNECTED
- ADDR_CHANGE
- DEVICE_REMOVAL
- TIMEWAIT_EXIT

Only in DISCONNECTED/ADDR_CHANGE it makes sense to
call rdma_disconnect (send DREQ/DREP to our initiator).
So we keep the same teardown handler for all of them
but only indicate calling rdma_disconnect for the relevant
events.

This patch also removes redundant debug prints for each single
event.

v2 changes:
 - Call isert_disconnected_handler() for DEVICE_REMOVAL (Or + Sag)
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In ungraceful teardowns isert close flows seem racy such that
isert_wait_conn hangs as RDMA_CM_EVENT_DISCONNECTED never
gets invoked (no one called rdma_disconnect).

Both graceful and ungraceful teardowns will have rx flush errors
(isert posts a batch once connection is established). Once all
flush errors are consumed we invoke isert_wait_conn and it will
be responsible for calling rdma_disconnect. This way it can be
sure that rdma_disconnect was called and it won't wait forever.

This patch also removes the logout_posted indicator. either the
logout completion was consumed and no problem decrementing the
post_send_buf_count, or it was consumed as a flush error. no point
of keeping it for isert_wait_conn as there is no danger that
isert_conn will be accidentally removed while it is running.

(Drop unnecessary sleep_on_conn_wait_comp check in
 isert_cq_rx_comp_err - nab)
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case np_thread state is in RESET/SHUTDOWN/EXIT states,
no point for isert to stall there as we may get a hang in
case no one will wake it up later.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

When the target is in stop stage, iSER transport initiates RDMA disconnects.
The iSER initiator may wish to establish a new connection over the
still existing network portal. In this case iSER transport should not
accept and resume new RDMA connections. In order to learn that, iscsi_np
is added with enabled flag so the iSER transport can check when deciding
weather to accept and resume a new connection request.

The iscsi_np is enabled after successful transport setup, and disabled
before iscsi_np login threads are cleaned up.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

RDMA CM and iSCSI target flows are asynchronous and completely
uncorrelated. Relying on the fact that iscsi_accept_np will be called
after CM connection request event and will wait for it is a mistake.

When attempting to login to a few targets this flow is racy and
unpredictable, but for parallel login to dozens of targets will
race and hang every time.

The correct synchronizing mechanism in this case is pending on
a semaphore rather than a wait_for_event. We keep the pending
interruptible for iscsi_np cleanup stage.

(Squash patch to remove dead code into parent - nab)
Reported-by: NSlava Shwartsman <valyushash@gmail.com>
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Should be adding list_add_tail($new, $head) and not
the other way around.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In order to support local WRITE_INSERT + READ_STRIP operations for
non PI enabled fabrics, the fabric driver needs to be able signal
what protection offload operations are supported.

This is done at session initialization time so the modes can be
signaled by individual se_wwn + se_portal_group endpoints, as well
as optionally across different transports on the same endpoint.

For iser-target, set TARGET_PROT_ALL if the underlying ib_device
has already signaled PI offload support, and allow this to be
exposed via a new iscsit_transport->iscsit_get_sup_prot_ops()
callback.

For loopback, set TARGET_PROT_ALL to signal SCSI initiator mode
operation.

For all other drivers, set TARGET_PROT_NORMAL to disable fabric
level PI.

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Fastreg is mandatory for signature, so if the
device doesn't support it we don't need to use it.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a bug where outstanding RDMA_READs with WRITE_PENDING
status require an extra target_put_sess_cmd() in isert_put_cmd() code
when called from isert_cq_tx_comp_err() + isert_cq_drain_comp_llist()
context during session shutdown.

The extra kref PUT is required so that transport_generic_free_cmd()
invokes the last target_put_sess_cmd() -> target_release_cmd_kref(),
which will complete(&se_cmd->cmd_wait_comp) the outstanding se_cmd
descriptor with WRITE_PENDING status, and awake the completion in
target_wait_for_sess_cmds() to invoke TFO->release_cmd().

The bug was manifesting itself in target_wait_for_sess_cmds() where
a se_cmd descriptor with WRITE_PENDING status would end up sleeping
indefinately.
Acked-by: NSagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: <stable@vger.kernel.org> #3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Now that TASK_ABORTED status is not generated for all cases by
TMR ABORT_TASK + LUN_RESET, a new TFO->abort_task() caller is
necessary in order to give fabric drivers a chance to unmap
hardware / software resources before the se_cmd descriptor is
released via the normal TFO->release_cmd() codepath.

This patch adds TFO->aborted_task() in core_tmr_abort_task()
in place of the original transport_send_task_abort(), and
also updates all fabric drivers to implement this caller.

The fabric drivers that include changes to perform cleanup
via ->aborted_task() are:

  - iscsi-target
  - iser-target
  - srpt
  - tcm_qla2xxx

The fabric drivers that currently set ->aborted_task() to
NOPs are:

  - loopback
  - tcm_fc
  - usb-gadget
  - sbp-target
  - vhost-scsi

For the latter five, there appears to be no additional cleanup
required before invoking TFO->release_cmd() to release the
se_cmd descriptor.

v2 changes:
  - Move ->aborted_task() call into transport_cmd_finish_abort (Alex)

Cc: Alex Leung <amleung21@yahoo.com>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Vu Pham <vu@mellanox.com>
Cc: Chris Boot <bootc@bootc.net>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch changes isert_conn_create_fastreg_pool() to follow
logic in iscsi_target_locate_portal() for determining how many
FRMR descriptors to allocate based upon the number of possible
per-session command slots that are available.

This addresses an OOPs in isert_reg_rdma() where due to the
use of ISCSI_DEF_XMIT_CMDS_MAX could end up returning a bogus
fast_reg_descriptor when the number of active tags exceeded
the original hardcoded max.

Note this also includes moving isert_conn_create_fastreg_pool()
from isert_connect_request() to isert_put_login_tx() before
posting the final Login Response PDU in order to determine the
se_nacl->queue_depth (eg: number of tags) per session the target
will be enforcing.

v2 changes:
  - Move isert_conn->conn_fr_pool list_head init into
    isert_conn_request()
v3 changes:
  - Drop unnecessary list_empty() check in isert_reg_rdma()
    (Sagi)

Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: <stable@vger.kernel.org> #3.12+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

If during data-transfer a data-integrity error was detected we
must fail the command with CHECK_CONDITION and not execute
the command.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Reported-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Remove code duplication from RDMA_READ and RDMA_WRITE
completions that do basically the same check.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

If protection is involved, iSER target must wait for
completion of RDMA_READ before sending SCSI response.
So we must consider that when calculating post_send_buf_count
additions, also when processing good/error completions.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

As REG_SIG_MR work request and it's LOCAL_INVALIDATE are
not accounted in post_send_buf_count we must color these
with ISER_FASTREG_LI_WRID in order to process their error
completions when the QP flushes.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case the Target core passed transport T10 protection
operation:

1. Register data buffer (data memory region)
2. Register protection buffer if exsists (prot memory region)
3. Register signature region (signature memory region)
   - use work request IB_WR_REG_SIG_MR
4. Execute RDMA
5. Upon RDMA completion check the signature status
   - if succeeded send good SCSI response
   - if failed send SCSI bad response with appropriate sense buffer

(Fix up compile error in isert_reg_sig_mr, and fix up incorrect
 se_cmd->prot_type -> TARGET_PROT_NORMAL comparision - nab)
(Fix failed sector assignment in isert_completion_rdma_* - Sagi + nab)
(Fix enum assignements for protection type - Sagi)
(Fix devision on 32-bit in isert_completion_rdma_* - Sagi + Fengguang)
(Fix context change for v3.14-rc6 code - nab)
(Fix iscsit_build_rsp_pdu inc_statsn flag usage - nab)
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case of protected transactions, we will need to check the
protection status of the transaction before sending SCSI response.
So be ready for RDMA_WRITE completions. currently we don't ask
for these completions, but for T10-PI we will.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Introduce pi_context to hold relevant RDMA protection resources.
We eliminate data_key_valid boolean and replace it with indicators
container to indicate:
- Is the descriptor protected (registered via signature MR)
- Is the data_mr key valid (can spare LOCAL_INV WR)
- Is the prot_mr key valid (can spare LOCAL_INV WR)
- Is the sig_mr key valid (can spare LOCAL_INV WR)

Upon connection establishment check if network portal is T10-PI
enabled and allocate T10-PI resources if necessary, allocate
signature enabled memory regions and mark connection queue-pair
as signature enabled.

(Fix context change for v3.14-rc6 code - nab)
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

export map/unmap data buffer to a routine that may
be used in various places in the code and keep the
mapping data in a designated descriptor. Also, let
isert_fast_reg_mr to decide weather to use global
MR or do fast registration.

This commit does not change any functionality.

(Fix context change for v3.14-rc6 code - nab)
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses a number of active I/O shutdown issues
related to isert_cmd descriptors being leaked that are part
of a completion interrupt coalescing batch.

This includes adding logic in isert_cq_tx_comp_err() to
drain any associated tx_desc->comp_llnode_batch, as well
as isert_cq_drain_comp_llist() to drain any associated
isert_conn->conn_comp_llist.

Also, set tx_desc->llnode_active in isert_init_send_wr()
in order to determine when work requests need to be skipped
in isert_cq_tx_work() exception path code.

Finally, update isert_init_send_wr() to only allow interrupt
coalescing when ISER_CONN_UP.
Acked-by: NSagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: <stable@vger.kernel.org> #3.13+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>