Simplify iser QP creation by splitting some unrelated
logic bulks to routines.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

No need to cast void pointers.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

No need for this assignment.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

unmap_list is unused.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We have a switch default for this.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This is to favor the HCA cache hit rate using less MRs
and PDs. This commit partially reverts commit:
"eb6ab132 IB/isert: separate connection protection domains and dma MRs"

At the time I thought this would be needed.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Before we reach to connection established we may get an
error event. In this case the core won't teardown this
connection (never established it), so we take care of freeing
it ourselves.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This hang was a result of a missing command put when
a DIF error occurred during a rdma read (and we sent
an CHECK_CONDITION error without passing it to the
backend).
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case sendtargets response is larger than initiator MRDSL, we
send a partial sendtargets response (setting F=0, C=1, TTT!=0xffffffff),
accept a consecutive empty text message and send the rest of the payload.
In case we are done, we set F=1, C=0, TTT=0xffffffff.
We do that by storing the sendtargets response bytes done under
the session.

This patch also makes iscsit_find_cmd_from_itt public for isert.

(Re-add cmd->maxcmdsn_inc and clear in iscsit_build_text_rsp - nab)
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The macro isert_dbg already ensures that __func__ is part of the
output, so there's no reason to duplicate the function name in the
format string itself.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

if text message dlength is 0, don't allocate a buffer for it, pass
NULL to iscsit_process_text_cmd.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Bound workqueues might be too restrictive since they allow
only a single core per session for processing completions.
WQ_UNBOUND will allow bouncing to another CPU if the running
CPU is currently busy. Luckily, our workqueues are NUMA aware
and will first try to bounce within the same NUMA socket.
My measurements with NULL backend devices show that there is
no (noticeable) additional latency as a result of the change.
I'd expect even to gain performance when working with fast
devices that also allocate MSIX interrupt vectors.

While we're at it, make it WQ_HIGHPRI since processing
completions is really a high priority for performance.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Reported-by: NMoussa Ba <moussaba@micron.com>
Signed-off-by: NMoussa Ba <moussaba@micron.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We are sending text response and not reject.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

isert_debug_level should be static, hence no need
to initialize it.
Reported-by: NShachar Raindel <raindel@mellanox.com>
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

CC [M]  drivers/infiniband/ulp/isert/ib_isert.o
drivers/infiniband/ulp/isert/ib_isert.c: In function ‘isert_cq_comp_err’:
drivers/infiniband/ulp/isert/ib_isert.c:1979:42: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

- Fall-through in switch case instead in do_control_comp.
- Move rkey invalidation to a function.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

debug_level 1 (warn): Include warning messages.
debug_level 2 (info): Include relevant info for control plane.
debug_level 3 (debug): Include relevant info in the IO path.

Also, added/removed some logging messages.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Personal preference, easier control of the log level with
a single modparam which can be changed dynamically. Allows
better saparation of control and IO plains.

Replaced throughout ib_isert.c:
s/pr_debug/isert_dbg/g
s/pr_info/isert_info/g
s/pr_warn/isert_warn/g
s/pr_err/isert_err/g

Plus nit checkpatch warning change.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We don't want to wait for conn_logout_comp from isert_comp_wq
context as this blocks further completions from being processed.
Instead we wait for it conditionally (if logout response was
actually posted) in wait_conn. This wait should normally happen
immediately as it occurs after we consumed all the completions
(including flush errors) and conn_logout_comp should have been
completed.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Might result in a deadlock where completion context waits for
session commands release where the later might need a final
completion for it.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In order to reduce the contention on CQ locking (present
in some LLDDs) we poll in batches of 16 work completion items.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case the CQ is packed with completions, we can't just
hog the CPU forever. Poll until a sufficient budget (currently
hard-coded to 64k completions) and if budget is exhausted, bailout
and give a chance to other threads.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In order to know that we consumed all the connection completions
we maintain atomic post_send_buf_count for each IO post send. But
we can know that if we post a "beacon" (zero length RECV work request)
after we move the QP into error state and the target does not serve
any new IO. When we consume it, we know we finished all the connection
completion and we can go ahead and destroy stuff.

In error completion handler we now just need to check for ISERT_BEACON_WRID
to arrive and then wait for session commands to cleanup and complete
conn_wait_comp_err.

We reserve another CQ and QP entries to fit the zero length post recv.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We are calling session reinstatement, wait_conn will start
connection termination.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Using TX and RX CQs attached to the same vector might
create a throttling effect coming from the serial processing
of a work-queue. Use one CQ instead, it will do better in interrupt
processing and it provides a simpler code. Also, We get rid of
redundant isert_rx_wq.

Next we can remove the atomic post_send_buf_count from the IO path.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

A pre-step before going to a single CQ.
Also this makes the code a little more simple to
read.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Nit, uintptr_t is designed for pointer casting, use it.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

As a pre-step to a single CQ, we unite the error completion
handlers to a single handler.

This patch does not change any functionality.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

It is disabled at the moment, we will get that back
in once the target is more stable.

This reverts commit 95b60f07
"Add support for completion interrupt coalescing"
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Currently we have no way to tell that the target stack is in shutdown
sequence. In case we have open connections, the initiator immediately
attempts to reconnect in a DDOS attack style, so we may end up
terminating the iser enabled network portal while it's np_accept_list
still have pending connections.

The workaround is simply release all the connections in the list.
A proper fix will be to start shutdown sequence by shutting the
network portal to avoid initiator immediate reconnect attempts.

But the temporary work around seems to work at this point, so I think
we can do this for now...
Reported-by: NSlava Shwartsman <valyushash@gmail.com>
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

iSER will report supported protection operations based on
the tpg attribute t10_pi settings and HCA PI offload capabilities.
If the HCA does not support PI offload or tpg attribute t10_pi is
not set, we fall to SW PI mode.

In order to do that, we move iscsit_get_sup_prot_ops after connection
tpg assignment.
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Fallback to software mode DIF if HCA does not support
PI (without crashing obviously). It is still possible to
run with backend protection and an unprotected frontend,
so looking at the command prot_op is not enough. Check
device PI capability on a per-IO basis (isert_prot_cmd
inline static) to determine if we need to handle protection
information.

Trace:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffffa037f8b1>] isert_reg_sig_mr+0x351/0x3b0 [ib_isert]
Call Trace:
 [<ffffffff812b003a>] ? swiotlb_map_sg_attrs+0x7a/0x130
 [<ffffffffa038184d>] isert_reg_rdma+0x2fd/0x370 [ib_isert]
 [<ffffffff8108f2ec>] ? idle_balance+0x6c/0x2c0
 [<ffffffffa0382b68>] isert_put_datain+0x68/0x210 [ib_isert]
 [<ffffffffa02acf5b>] lio_queue_data_in+0x2b/0x30 [iscsi_target_mod]
 [<ffffffffa02306eb>] target_complete_ok_work+0x21b/0x310 [target_core_mod]
 [<ffffffff8106ece2>] process_one_work+0x182/0x3b0
 [<ffffffff8106fda0>] worker_thread+0x120/0x3c0
 [<ffffffff8106fc80>] ? maybe_create_worker+0x190/0x190
 [<ffffffff8107594e>] kthread+0xce/0xf0
 [<ffffffff81075880>] ? kthread_freezable_should_stop+0x70/0x70
 [<ffffffff8159a22c>] ret_from_fork+0x7c/0xb0
 [<ffffffff81075880>] ? kthread_freezable_should_stop+0x70/0x70
Reported-by: NSlava Shwartsman <valyushash@gmail.com>
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch converts to allocate PI contexts dynamically in order
avoid a potentially bogus np->tpg_np and associated NULL pointer
dereference in isert_connect_request() during iser-target endpoint
shutdown with multiple network portals.

Also, there is really no need to allocate these at connection
establishment since it is not guaranteed that all the IOs on
that connection will be to a PI formatted device.

We can do it in a lazy fashion so the initial burst will have a
transient slow down, but very fast all IOs will allocate a PI
context.

Squashed:

iser-target: Centralize PI context handling code
Signed-off-by: NSagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In situations such as bond failover, The new session establishment
implicitly invokes the termination of the old connection.

So, we don't want to wait for the old connection wait_conn to completely
terminate before we accept the new connection and post a login response.

The solution is to deffer the comp_wait completion and the conn_put to
a work so wait_conn will effectively be non-blocking (flush errors are
assumed to come very fast).

We allocate isert_release_wq with WQ_UNBOUND and WQ_UNBOUND_MAX_ACTIVE
to spread the concurrency of release works.
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>

The np listener cm_id will also get ADDR_CHANGE event
upcall (in case it is bound to a specific IP). Handle
it correctly by creating a new cm_id and implicitly
destroy the old one.

Since this is the second event a listener np cm_id may
encounter, we move the np cm_id event handling to a
routine.

Squashed:

iser-target: Move cma_id setup to a function
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>

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>