By always allocating and adding, respectively removing and freeing
the se_node_acl structure in core code we can remove tons of repeated
code in the init_nodeacl and drop_nodeacl routines.  Additionally
this now respects the get_default_queue_depth method in this code
path as well.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

All fabric drivers except for iSCSI always return 1, so implement
that as default behavior.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The first argument of these two functions is always identical
to se_cmd->se_sess. Hence remove the first argument.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NSagi Grimberg <sagig@mellanox.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: <qla2xxx-upstream@qlogic.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There is just one configfs subsystem in the target code, so we might as
well add two helpers to reference / unreference it from the core code
instead of passing pointers to it around.

This fixes a regression introduced for v4.1-rc1 with commit 9ac8928e,
where configfs_depend_item() callers using se_tpg_tfo->tf_subsys would
fail, because the assignment from the original target_core_subsystem[]
is no longer happening at target_register_template() time.

(Fix target_core_exit_configfs pointer dereference - Sagi)
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Instead of calling target_fabric_configfs_init() +
target_fabric_configfs_register() / target_fabric_configfs_deregister()
target_fabric_configfs_free() from every target driver, rewrite the API
so that we have simple register/unregister functions that operate on
a const operations vector.

This patch also fixes a memory leak in several target drivers. Several
target drivers namely called target_fabric_configfs_deregister()
without calling target_fabric_configfs_free().

A large part of this patch is based on earlier changes from
Bart Van Assche <bart.vanassche@sandisk.com>.

(v2: Add a new TF_CIT_SETUP_DRV macro so that the core configfs code
can declare attributes as either core only or for drivers)
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch updates qla2xxx target to add a new fabric_prot_type TPG
attribute, used for controlling LLD level protection into LIO when
the backend device does not support T10-PI.

This is required for qla_target.c to enable WRITE_STRIP + READ_INSERT
hardware offloads.

It's disabled by default and controls which se_sesion->sess_prot_type
are set at tcm_qla2xxx_check_initiator_node_acl() session registration
time.

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

This patch adds the missing TARGET_PROT_ALL when initializing a new
session and declaring the capable se_sess->sup_prot_ops for T10-PI.

This is required in order to function with existing qla_target.c
DIF protection offload support.

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

This patch fixes the incorrect use of __transport_register_session()
in tcm_qla2xxx_check_initiator_node_acl() code, that does not perform
explicit se_tpg->session_lock when accessing se_tpg->tpg_sess_list
to add new se_sess nodes.

Given that tcm_qla2xxx_check_initiator_node_acl() is not called with
qla_hw->hardware_lock held for all accesses of ->tpg_sess_list, the
code should be using transport_register_session() instead.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: <stable@vger.kernel.org> # 3.5+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch exposes a new ../qla2xxx*/$WWPN/$TPGT/dynamic_sessions
attribute to dump the currently active sessions by FC initiator WWPN
that have been created with dynamically generated se_node_acls.

This information is useful so that user-space can optionally perform
dynamic -> explicit NodeACL conversion based on $INITIATOR_WWPN.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Instead of pushing each byte via stack let's use custom specifier which allows
to print small buffers as a hex string.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The code is currently riddled with "drop the hardware_lock to avoid a
deadlock" bugs that expose races.  One of those races seems to expose a
valid warning in tcm_qla2xxx_clear_nacl_from_fcport_map.  Add some
bandaid to it.
Signed-off-by: NJoern Engel <joern@logfs.org>
Cc: <stable@vger.kernel.org> # v3.5+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: NSaurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NGiridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

tcm_qla2xxx_get_task_tag incorrectly assume command is
qla_tgt_cmd.  Add check to see if it's a scsi cmd or
task mgmt command.
Signed-off-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NSaurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NSaurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This patch converts qla2xxx target code to use generic percpu_ida
tag allocation provided by target-core, thus removing the original
kmem_cache_zalloc() for each struct qla_tgt_cmd descriptor in the
incoming ATIO packet fast-path.

This includes the conversion of qlt_handle_cmd_for_atio() to perform
qla_tgt_sess lookup before dispatching a command descriptor into
qla_tgt_wq process context, along with handling the case where no
active session exists, and subsequently kicking off a seperate
process context for qlt_create_sess_from_atio() to create a new one.

It also includes moving tag allocation into generic code within
qlt_get_tag(), so that the same logic can be shared between
qlt_handle_cmd_for_atio() + qlt_create_sess_from_atio() contexts.
Also, __qlt_do_work() has been made generic between both normal
process context in qlt_do_work() + qlt_create_sess_from_atio().

Next, update qlt_free_cmd() to release the percpu-ida tags, and
drop the now-unused global qla_tgt_cmd_cachep.

Finally in tcm_qla2xxx code, tcm_qla2xxx_check_initiator_node_acl()
has been updated to use transport_init_session_tags() along with a
hardcoded TCM_QLA2XXX_DEFAULT_TAGS=2088 as the number of qla_tgt_cmd
descriptors to pre-allocate per qla_tgt_sess instance.

(Use ha->fw_xcb_count if available to calculate num_tags, and
 also factor in extra pad tags - Quinn)

Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Add support for T10-Dif for Target Mode to qla driver.
The driver will look for firmware attribute that support
this feature.  When the feature is present, the capabilities
will be report to TCM layer.

Add CTIO CRC2 iocb to build T10-Dif commands.
Add support routines to process good & error cases.
Signed-off-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: NGiridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NSaurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

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>

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 fixes the NAA formatted name used by EVPD=0x83
device identifer to reflect the proper NPIV enabled WWPN.

Cc: Sawan Chandak <sawan.chandak@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch performs configfs_depend_item() during TPG enable for
base_tpg (eg: non-NPIV) ports, and configfs_undepend_item() during
TPG disable for base_tpg.

This is done to ensure that any attempt to configfs rmdir a base_tpg
with active NPIV ports will fail with -EBUSY, until all associated
NPIV ports have been explicitly shutdown and base_tpg disabled.

Note that the actual configfs_[un]depend_item() is done from seperate
process context, as these are not intended to be called directly
from configfs callbacks.

Cc: Sawan Chandak <sawan.chandak@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds seperate logic for NPIV specific enable/disable
attribute logic, as NPIV vs. non-NPIV enable/disable ends up being
different enough to warrent seperate logic for setting configfs
tpg_group dependencies in the non-NPIV case.

Cc: Sawan Chandak <sawan.chandak@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch changes qla2xxx qlt_lport_register() code to accept
target_lport_ptr + npiv_wwpn + npiv_wwnn parameters, and updates
tcm_qla2xxx to use the new tcm_qla2xxx_lport_register_npiv_cb()
callback for invoking fc_vport_create() from configfs context
via tcm_qla2xxx_npiv_make_lport() code.

In order for this to work, the qlt_lport_register() callback is
now called without holding qla_tgt_mutex, as the fc_vport creation
process will call qlt_vport_create() -> qlt_add_target(), which
already expects to acquire it.

It enforces /sys/kernel/config/target/qla2xxx_npiv/$NPIV_WWPN
naming in the following format:

     $PHYSICAL_WWPN@$NPIV_WWPN:$NPIV_WWNN

and assumes the $PHYSICAL_WWPN in question has already had been
configured for target mode in non NPIV mode.

Finally, it updates existing tcm_qla2xxx_lport_register_cb() logic
to setup the non NPIV assignments that have now been moved out of
qlt_lport_register() code.

Cc: Sawan Chandak <sawan.chandak@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: NSawan Chandak <sawan.chandak@qlogic.com>
Signed-off-by: NQuinn Tran <quinn.tran@qlogic.com>
Signed-off-by: NSaurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Just a dereference, don't need a macro.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Remove a lingering macro that just hid a dereference.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Update copyright ownership/year information for target-core,
loopback, iscsi-target, tcm_qla2xx, vhost and iser-target.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Reversing the dma_data_direction for pci_map_sg() friends is useful
for other drivers, so move it from tcm_qla2xxx into inline code
within target_core_fabric.h.

Also drop internal usage of equivlient in tcm_qla2xxx fabric code.
Reported-by: NChristoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: NNicholas Bellinger <nab@daterainc.com>

The patch changes a specifier used to output some variables. Instead of using
stack for each byte the '%*ph[CN]' allows to take a one pointer and prints
entire buffer as a hexadecimal string with the separator ':' or ''.
Signed-off-by: NOleksandr Khoshaba <Oleksandr.Khoshaba@gmail.com>
Signed-off-by: NSaurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Changing this attribute to 0 will mean that all initiators that login
to the target while the target has generate_node_acls=1 will see all
TPG LUNs, which may be the desired behavior in some cases.

(nab: Apply patch without macro changes)
Reported-by: NCraig Watson <craig.watson@vanguard-rugged.com>
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The return value wasn't checked by any of the callers.  Assuming this is
correct behaviour, we can simplify some code by not bothering to
generate it.

nab: Add srpt_queue_data_in() + srpt_queue_tm_rsp() nops around
     srpt_queue_response() void return
Signed-off-by: NJoern Engel <joern@logfs.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Comment from original 2012 patch:
  In all our testing this function has never returned true.  However, the
  dropping of hardware_lock necessary to call this function seems to cause
  a use-after-free we manage to hit rather frequently.  Given this
  cost-benefit ratio, I'm willing to remove some 100 lines of code.

And since the same problem exists around shutdown_sess and put_sess,
this patch changes them from taking the hardware_lock to requiring the
hardware_lock to be taken.  In most cases the caller already had the
lock and had to drop it for the called method to reacquire it.  At best
that hurts performance and in rare instances it causes races with fatal
consequences.

We dropped the original 2012 patch when upgrading our kernel and it took
us nearly half a year to discover we still need it.

(nab: Fix qla_tgt_sess reference in tcm_qla2xxx_put_sess)
Signed-off-by: NJoern Engel <joern@logfs.org>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Suppose an initiator sends a DATA IN command with an allocation length
shorter than the FC transfer length -- we get a target message like

    TARGET_CORE[qla2xxx]: Expected Transfer Length: 256 does not match SCSI CDB Length: 0 for SAM Opcode: 0x12

In that case, the target core adjusts the data_length and sets
se_cmd->residual_count for the underrun.  But now suppose that command
fails and we end up in tcm_qla2xxx_queue_status() -- that function
unconditionally overwrites residual_count with the already adjusted
data_length, and the initiator will burp with a message like

    qla2xxx [0000:00:06.0]-301d:0: Dropped frame(s) detected (0x100 of 0x100 bytes).

Fix this by adding on to the existing underflow residual count instead.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Drop unused transport_wait_for_tasks() check in target_wait_for_sess_cmds
shutdown code, and convert tcm_qla2xxx + ib_srpt fabric drivers.

Cc: Joern Engel <joern@logfs.org>
Cc: Roland Dreier <roland@kernel.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Pass the sense reason as an explicit return value from the I/O submission
path instead of storing it in struct se_cmd and using negative return
values.  This cleans up a lot of the code pathes, and with the sparse
annotations for the new sense_reason_t type allows for much better
error checking.

(nab: Convert spc_emulate_modesense + spc_emulate_modeselect to use
      sense_reason_t with Roland's MODE SELECT changes)
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Correct spelling typo in debug messages within qla2xxx drivers.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

It is possible for the target code to change the loop_id or s_id of a
target session in reaction to an FC fabric change.  However, the
session structures are stored in tables that are indexed by these two
keys, and if we just change the session structure but leave the
pointers to it in the old places in the table, havoc can ensue.  For
example, a new session might come along that should go in the old slot
in the table and overwrite the old session pointer.

To handle this, add a new tgt_ops->update_sess() method that also
updates the "by loop_id" and "by s_id" lookup tables when a session
changes, so that the keys where a session pointer is stored in these
tables always matches the keys in the session structure itself.

(nab: Drop unnecessary double inversion with FCF_CONF_COMP_SUPPORTED
      usage)
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

My draft of SPC-4 says the following about the SCSI name string in
inquiry VPD page 83h:

    The SCSI NAME STRING field starts with either:

    a) the four UTF-8 characters 'eui.' concatenated with 16, 24, or
       32 hexadecimal digits (i.e., the UTF-8 characters 0 through 9
       and A through F) for an EUI-64 based identifier (see
       7.8.6.5). The first hexadecimal digit shall be the most
       significant four bits of the first byte (i.e., most significant
       byte) of the EUI-64 based identifier;
    b) the four UTF-8 characters 'naa.' concatenated with 16 or 32
       hexadecimal digits for an NAA identifier (see 7.8.6.6). The
       first hexadecimal digit shall be the most significant four bits
       of the first byte (i.e., most significant byte) of the NAA
       identifier; or
    c) the four UTF-8 characters 'iqn.' concatenated with an iSCSI
       Name for an iSCSI-name based identifier (see iSCSI).

However, the .tpg_get_wwn method for tcm_qla2xxx formats the WWN so
the SCSI name string looks like "52:4a:93:7d:24:5f:b2:12,t,0x0001".
This patch corrects the code so that VPD 83h gives a SPC-compliant
SCSI name string like "naa.524a937d245fb212,t,0x0001" while leavig
other uses alone (so configfs will still work with ':' separated WWNs).
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Every fabric driver has to supply a se_tfo->set_fabric_sense_len()
method, just so iSCSI can return an offset of 2.  However, every fabric
driver is already allocating a sense buffer and passing it into the
target core, either via transport_init_se_cmd() or target_submit_cmd().

So instead of having iSCSI pass the start of its sense buffer into the
core and then later tell the core to skip the first 2 bytes, it seems
easier for iSCSI just to do the offset of 2 when it passes the sense
buffer into the core.  Then we can drop the se_tfo->set_fabric_sense_len()
everywhere, and just add a couple of lines of code to iSCSI to set the
sense data length to the beginning of the buffer right before it sends
it over the network.

(nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops +
      change transport_get_sense_buffer to follow v3.6-rc6 code w/o
      ->set_fabric_sense_len usage)
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There are no callers of se_tfo->get_fabric_sense_len(), so we should
stop having every fabric driver implement it.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We want it to be possible for target_submit_cmd() to return errors up
to its fabric module callers.  For now just update the prototype to
return an int, and update all callers to handle non-zero return values
as an error.

This is immediately useful for tcm_qla2xxx to fix a long-standing active
I/O session shutdown race, but tcm_fc, usb-gadget, and sbp-target the
fabric maintainers need to check + ACK that handling a target_submit_cmd()
failure due to session shutdown does not introduce regressions

(nab: Respin against for-next after initial NACK + update docbook comment +
      fix double se_cmd init in exception path for usb-gadget)

Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Cc: Chris Boot <bootc@bootc.net>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>