Move the entirely bio allocation, mapping and submission into ->do_task.
This

 a) avoids blocking the I/O submission thread unessecarily, and
 b) simplifies the code greatly
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds a minor simplfication in target_parse_naa_6h_vendor_specific()
to remove direct isxdigit() + ctype.h usage.

(nab: Fix next assignment breakage in for loop)
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch removes the unnecessary session_reinstatement parameter from
se_cmd->transport_wait_for_tasks(), logic in transport_generic_wait_for_tasks,
and usage within iscsi-target code.

This also includes the removal of the 'bool' return from transport_put_cmd() +
transport_generic_free_cmd() that is no longer necessary.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Push session reinstatement out of transport_generic_free_cmd into the only
caller that actually needs it.  Clean up transport_generic_free_cmd a bit,
and remove the useless comment.  I'd love to add a more useful kerneldoc
comment for it, but as this point I'm still a bit confused in where it
stands in the command release stack.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

All callers that never have the session_reinstatement flag set can trivially
be converted to transport_put_cmd.  Opencode the session reinstatement code
in transport_generic_free_cmd, which was the only caller ever asking for it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Inline two simple functions only used by it, and replace a goto
with a simple if else construct.

Note that the code moved from transport_dec_and_check seems fairly
buggy - the atomic_read check on a variable where we'd do an
atomic_dec_and_test looks racy if we'll ever get someone increment
it without the lock held around them (which it looks like we do),
and not decrementing the second counter if the first one doesn't
hit zero also at least needs an explanation.

(nab: Fix transport_put_cmd breakage)
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Instead of duplicating the code from transport_release_fe_cmd re-use it by
allowing transport_release_fe_cmd to return wether it actually freed the
command or not.  Also rename transport_release_fe_cmd to transport_put_cmd
and add a kerneldoc comment for it to make the use case more obvious.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

It is only called by transport_release_cmd, so inline it there.  Also add
a kerneldoc comment for transport_release_cmd while we are at it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

iscsit_task_reassign_complete is always called from the TX thread, so
handle the CDB directly instead of offloading it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

ft_send_work is always called from workqueue context, which means we can
handle the CDB directly instead of doing another context switch.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a bug where transport_send_task_abort() could be called
during LUN_RESET to return SAM_STAT_TASK_ABORTED + tfo->queue_status(), when
SCF_SENT_CHECK_CONDITION -> tfo->queue_status() has already been sent from
within another context via transport_send_check_condition_and_sense().

Cc: stable@kernel.org
Signed-off-by: NNicholas Bellinger <nab@risingtidesystems.com>

This patch fixes a bug in LUN_RESET operation with transport_cmd_finish_abort()
where transport_remove_cmd_from_queue() was incorrectly being called, causing
descriptors with t_state == TRANSPORT_FREE_CMD_INTR to be incorrectly removed
from qobj->qobj_list during process context release.  This change ensures the
descriptor is only removed via transport_remove_cmd_from_queue() when doing a
direct release via transport_generic_remove().

Cc: stable@kernel.org
Signed-off-by: NNicholas Bellinger <nab@risingtidesystems.com>

This patch contains a bugfix for TMR LUN_RESET related to TRANSPORT_FREE_CMD_INTR
operation, where core_tmr_drain_cmd_list() will now skip processing for this
case to prevent an ABORT_TASK status from being returned for descriptors that
are already queued up to be released by processing thread context.

Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: NNicholas Bellinger <nab@risingtidesystems.com>

This patch is a re-orginzation of core_tmr_lun_reset() logic to properly
scan the active tmr_list, dev->state_task_list and qobj->qobj_list w/ the
relivent locks held, and performing a list_move_tail onto seperate local
scope lists before performing the full drain.

This involves breaking out the code into three seperate list specific
functions: core_tmr_drain_tmr_list(), core_tmr_drain_task_list() and
core_tmr_drain_cmd_list().

(nab: Include target: Remove non-active tasks from execute list during
      LUN_RESET patch to address original breakage)
Reported-by: NRoland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: NNicholas Bellinger <nab@risingtidesystems.com>

This patch addresses a bug with the lio-core-2.6.git conversion of
transport_add_cmd_to_queue() to use a single embedded list_head, instead
of individual struct se_queue_req allocations allowing a single se_cmd to
be added to the queue mulitple times.  This was changed in the following:

commit 2a9e4d5ca5d99f4c600578d6285d45142e7e5208
Author: Andy Grover <agrover@redhat.com>
Date:   Tue Apr 26 17:45:51 2011 -0700

    target: Embed qr in struct se_cmd

The problem is that some target code still assumes performing multiple
adds is allowed via transport_add_cmd_to_queue(), which ends up causing
list corruption in qobj->qobj_list code.  This patch addresses this
by removing an existing struct se_cmd from the list before the add, and
removes an unnecessary list walk in transport_remove_cmd_from_queue()

It also changes cmd->t_transport_queue_active to use explict sets intead
of increment/decrement to prevent confusion during exception path handling.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@kernel.org
Signed-off-by: NNicholas Bellinger <nab@risingtidesystems.com>

It was pointed out by 'make versioncheck' that some includes of
linux/version.h are not needed in drivers/target/.
This patch removes them.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a bug in the iscsit_fe_sendpage_sg() transmit codepath that
was originally introduced with the v3.1 iscsi-target merge that incorrectly
uses hardcoded cmd->iov_data_count values to determine cmd->iov_data[] offsets
for extra outgoing padding and DataDigest payload vectors.

This code is obviously incorrect for the DataDigest enabled case with sendpage
offload, and this fix ensures correct operation for padding + DataDigest,
padding only, and DataDigest only cases.  The bug was introduced during a
pre-merge change in iscsit_fe_sendpage_sg() to natively use struct scatterlist
instead of the legacy v3.0 struct se_mem logic.

Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch makes iscsi-target explictly disable OFMarker=Yes and IFMarker=yes
parameter key usage during iscsi login by setting IFMarkInt_Reject and
OFMarkInt_Reject values in iscsi_enforce_integrity_rules() to effectively
disable iscsi marker usage.  With this patch, an initiator proposer asking
to enable either marker parameter keys will be issued a 'No' response, and
the target sets OFMarkInt + IFMarkInt parameter key response to 'Irrelevant'.

With markers disabled during iscsi login, this patch removes the problematic
on-stack local-scope array for marker intervals in iscsit_do_rx_data() +
iscsit_do_tx_data(), and other related marker code in iscsi_target_util.c.
This fixes a potentional stack smashing scenario with small range markers
enabled and a large MRDSL as reported by DanC here:

[bug report] target: stack can be smashed
http://www.spinics.net/lists/target-devel/msg00453.htmlReported-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds target_parse_naa_6h_vendor_specific() to address a bug where the
conversion of PRODUCT SERIAL NUMBER to use hex2bin() in target_emulate_evpd_83()
was not doing proper isxdigit() checking.  This conversion of the vpd_unit_serial
configifs attribute is done while generating a VPD=0x83 NAA IEEE Registered
Extended DESIGNATOR format's 100 bits of unique VENDOR SPECIFIC IDENTIFIER +
VENDOR SPECIFIC IDENTIFIER EXTENSION area.

This patch allows vpd_unit_serial (VPD=0x80) and the T10 Vendor ID DESIGNATOR
format (VPD=0x83) to continue to use free-form variable length ASCII values,
and now skips any non hex characters for fixed length NAA IEEE Registered Extended
DESIGNATOR format (VPD=0x83) requring the binary conversion.

This was originally reported by Martin after the v3.1-rc1 change to use hex2bin()
in commit 11650b85 where the use of non hex
characters in vpd_unit_serial generated different values than the original
v3.0 internal hex -> binary code.  This v3.1 change caused a problem with
filesystems who write a NAA DESIGNATOR onto it's ondisk metadata, and this patch
will (again) change existing values to ensure that non hex characters are not
included in the fixed length NAA DESIGNATOR.

Note this patch still expects vpd_unit_serial to be set via existing userspace
methods of uuid generation, and does not do strict formatting via configfs input.

The original bug report and thread can be found here:

NAA breakage
http://www.spinics.net/lists/target-devel/msg00477.html

The v3.1-rc1 formatting of VPD=0x83 w/o this patch:

VPD INQUIRY: Device Identification page
  Designation descriptor number 1, descriptor length: 20
    designator_type: NAA,  code_set: Binary
    associated with the addressed logical unit
      NAA 6, IEEE Company_id: 0x1405
      Vendor Specific Identifier: 0xffde35ebf
      Vendor Specific Identifier Extension: 0x3092f498ffa820f9
      [0x6001405ffde35ebf3092f498ffa820f9]
  Designation descriptor number 2, descriptor length: 56
    designator_type: T10 vendor identification,  code_set: ASCII
    associated with the addressed logical unit
      vendor id: LIO-ORG
      vendor specific: IBLOCK:ffde35ec-3092-4980-a820-917636ca54f1

The v3.1-final formatting of VPD=0x83 w/ this patch:

VPD INQUIRY: Device Identification page
  Designation descriptor number 1, descriptor length: 20
    designator_type: NAA,  code_set: Binary
    associated with the addressed logical unit
      NAA 6, IEEE Company_id: 0x1405
      Vendor Specific Identifier: 0xffde35ec3
      Vendor Specific Identifier Extension: 0x924980a82091763
      [0x6001405ffde35ec30924980a82091763]
  Designation descriptor number 2, descriptor length: 56
    designator_type: T10 vendor identification,  code_set: ASCII
    associated with the addressed logical unit
      vendor id: LIO-ORG
      vendor specific: IBLOCK:ffde35ec-3092-4980-a820-917636ca54f1

(v2: Fix parsing code to dereference + check for string terminator instead
     of null pointer to ensure a zeroed payload for vpd_unit_serial less
     than 100 bits of NAA DESIGNATOR VENDOR SPECIFIC area.  Also, remove
     the unnecessary bitwise assignment)
Reported-by: NMartin Svec <martin.svec@zoner.cz>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Problem: Changed from wake_up_interruptible -> wake_up_process and
wait_event_interruptible-> schedule_timeout_interruptible broke the FCoE
target.  Earlier approach of wake_up_interruptible was also looking at
'queue_cnt' which is not necessary, because it increment of 'queue_cnt'
with wake_up_inetrriptible / waker_up_process introduces race condition.

Fix: Instead of fixing the code which used wake_up_process and remove
'queue_cnt', using work_queue based approach is cleaner and acheives
same result. As well, work queue based approach has less programming
overhead and OS manages threads which processes work queues.

This patch is developed by Christoph Hellwig and reviwed+validated by
Kiran Patil.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKiran Patil <kiran.patil@intel.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Problem: HW DDP context wasn;t invalidated in case of ABORTS, etc...
This leads to the problem where memory pages which are used for DDP
as user descriptor could get reused for some other purpose (such as to
satisfy new memory allocation request either by kernel or user mode threads)
and since HW DDP context was not invalidated, HW continue to write to
those pages, hence causing memory corruption.

Fix: Either on incoming ABORTS or due to exchange time out, allowed the
target to cleanup HW DDP context if it was setup for respective ft_cmd.
Added new function to perform this cleanup, furthur it can be enhanced
for other cleanup activity.

Additinal Notes: To avoid calling ddp_done from multiple places, composed
the functionality in helper function "ft_invl_hw_context" and it is being
called from multiple places. Cleaned up code in function "ft_recv_write_data"
w.r.t DDP.
Signed-off-by: NKiran Patil <kiran.patil@intel.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

When work is scheduled with schedule_work(), the work can end up
running on multiple CPUs at the same time -- this happens if
the work is already running on one CPU and schedule_work() is called
on another CPU.  This leads to list corruption with target_qf_do_work(),
which is roughly doing:

	spin_lock(...);
	list_for_each_entry_safe(...) {
		list_del(...);
		spin_unlock(...);

		// do stuff

		spin_lock(...);
	}

With multiple CPUs running this code, one CPU can end up deleting the
list entry that the other CPU is about to work on.

Fix this by splicing the list entries onto a local list and then
operating on that in the work function.  This way, each invocation of
target_qf_do_work() operates on its own local list and so multiple
invocations don't corrupt each other's list.  This also avoids dropping
and reacquiring the lock for each list entry.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

With qla2xxx, acl_node_lock is taken inside qla2xxx's hardware_lock,
which is taken in hardirq context.  This means acl_node_lock must become
an IRQ-disabling lock; in particular this fixes lockdep warnings along
the lines of

    ======================================================
    [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]

     (&(&se_tpg->acl_node_lock)->rlock){+.....}, at: [<ffffffffa026f872>] transport_deregister_session+0x92/0x140 [target_core_mod]

    and this task is already holding:
     (&(&ha->hardware_lock)->rlock){-.-...}, at: [<ffffffffa017c5e7>] qla_tgt_stop_phase1+0x57/0x2c0 [qla2xxx]
    which would create a new lock dependency:
     (&(&ha->hardware_lock)->rlock){-.-...} -> (&(&se_tpg->acl_node_lock)->rlock){+.....}

    but this new dependency connects a HARDIRQ-irq-safe lock:
     (&(&ha->hardware_lock)->rlock){-.-...}

    to a HARDIRQ-irq-unsafe lock:
     (&(&se_tpg->acl_node_lock)->rlock){+.....}
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

At least the tcm_qla2xxx fabric driver calls into transport_deregister_session()
while holding an IRQ-disabled spinlock, so the inner locking needs to
use spin_lock_irqsave() instead of spin_lock_bh().

This fixes warnings seen with tcm_qla2xxx like:

    WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0x98/0xb0()
    Call Trace:
     [<ffffffff8104e65f>] warn_slowpath_common+0x7f/0xc0
     [<ffffffff8104e6ba>] warn_slowpath_null+0x1a/0x20
     [<ffffffff81055368>] local_bh_enable_ip+0x98/0xb0
     [<ffffffff814d5284>] _raw_spin_unlock_bh+0x14/0x20
     [<ffffffffa027b7f6>] transport_deregister_session+0x96/0x180 [target_core_mod]
     [<ffffffffa00f7731>] tcm_qla2xxx_free_session+0xd1/0x170 [tcm_qla2xxx]
     [<ffffffffa01b9173>] qla_tgt_sess_put+0xc3/0x140 [qla2xxx]
     [<ffffffffa01bf40f>] qla_tgt_stop_phase1+0x8f/0x2c0 [qla2xxx]
     [<ffffffffa00f735e>] tcm_qla2xxx_tpg_store_enable+0x6e/0xd0 [tcm_qla2xxx]
     [<ffffffffa026ca29>] target_fabric_tpg_attr_store+0x39/0x40 [target_core_mod]
     [<ffffffffa00a575d>] configfs_write_file+0xbd/0x120 [configfs]
     [<ffffffff811464a6>] vfs_write+0xc6/0x180
     [<ffffffff811467c1>] sys_write+0x51/0x90
     [<ffffffff814dd382>] system_call_fastpath+0x16/0x1b
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There's no need for the #ifdef protection when building into the kernel,
and in fact we need the module_init() for the initialization function to
be called.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Make a log message more useful by printing both the page and subpage
that an initiator is requesting.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes two bugs in allocation failure handling in
iscsit_allocate_se_cmd_for_tmr():

This first reported by DanC is a free-after call to transport_free_se_cmd(), this
patch drops the transport_free_se_cmd() call all together, as iscsit_release_cmd()
will release existing allocations as expected.

The second is a bug where iscsi_cmd_t was being leaked on a cmd->tmr_req allocation
failure, so make this jump to iscsit_release_cmd() as well.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The iSCSI target configfs code to print out an initiator's IPv6 address
is not fully implemented. This patch uses snprintf() with the "%pI6c"
format string to format the IPv6 address for display purposes.
Signed-off-by: NChris Boot <bootc@bootc.net>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes two bugs associated with transport_do_task_sg_chain()
operation where transport_allocate_data_tasks() was incorrectly setting
task_padded_sg for all tasks, and causing bogus task->task_sg_nents
assignments + OOPsen with fabrics depending upon this code.  The first bit
here adds a task_sg_nents_padded check in transport_allocate_data_tasks()
to include an extra SGL vector when necessary for tasks that expect to
be linked using sg_chain().

The second change involves making transport_do_task_sg_chain() properly
account for the extra SGL vector when task->task_padded_sg is set for
the non trailing ->task_sg or single ->task_sg allocations.  Note this
patch also removes the BUG_ON(!task->task_padded_sg) check within
transport_do_task_sg_chain() as we expect this to happen normally
with the updated logic in transport_allocate_data_tasks(), along with
being bogus for CONTROL_SG_IO_CDB type payloads.

So far this bugfix has been tested with tcm_qla2xxx and iblock backends
in (task_count > 1)( and (task_count == 1) operation.
Reported-by: NKiran Patil <kiran.patil@intel.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses recent breakage with multiple se_task (task_count > 1)
operation following backend dev->se_sub_dev->se_dev_attrib.max_sectors in new
transport_allocate_data_tasks() code.  The initial bug here was a bogus
task->task_sg_nents assignment in transport_allocate_data_tasks() based on
the passed parameter, which now uses DIV_ROUND_UP(task_size, PAGE_SIZE) to
determine the proper number of per task SGL entries for the (task_count > 1)
case.

This also means we now need to enforce a PAGE_SIZE aligned max_sector count
value for this to work as expected without bringing back the pre v3.1
transport_map_mem_to_sg() logic to handle SGL offsets across multiple tasks.
So this patch adds se_dev_align_max_sectors() to round down max_sectors as
necessary to ensure this alignment via se_dev_set_default_attribs() and
se_dev_align_max_sectors() and keeps it simple for (task_count > 1)
operation.

So far this bugfix has been tested with (task_count > 1) operation
using iscsi-target and iblock backends.
Reported-by: NChris Boot <bootc@bootc.net>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds the missing transport_cmd_get_valid_sectors() check for
SCF_SCSI_DATA_SG_IO_CDB type payloads to ensure that a received LBA + range
does not exeed past the end of associated backend struct se_device.

This patch also fixes a bug in the failure path of transport_new_cmd_obj()
where this check can fail, so change to use a signed 'rc' and return '-EINVAL'
to signal proper transport_generic_request_failure() handling.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a SYNCHRONIZE_CACHE CDB handling bug with IBLOCK/FILEIO
backends where transport_cmd_get_valid_sectors() was incorrectly rejecting
a zero LBA + range CDB from being processed, and returning CHECK_CONDITION.

This includes changing transport_cmd_get_valid_sectors() to return '0' on
success and '-EINVAL' on failure (this makes more sense than sectors),
and to only check transport_cmd_get_valid_sectors() when a non zero LBA +
range SYNCHRONIZE_CACHE operation has been receieved for the non passthrough
case.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch removes a duplicate set of transport_complete_task() calls in
target_emulate_unmap() and target_emulate_write_same() as the completion
call is already done within transport_emulate_control_cdb()

This patch also adds a check in transport_emulate_control_cdb() for the
existing SCF_EMULATE_CDB_ASYNC flag currently used by SYNCHRONIZE_CACHE
in order to handle IMMEDIATE processing.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

For all flavours of WRITE_SAME, we only expect to handle a single block
of data-out buffer payload, regardless of the number of logical blocks
presented in the CDB.  This patch changes all flavours of WRITE_SAME in
transport_generic_cmd_sequencer() to pass '1' into transport_get_size()
instead of the extracted 'sectors' to properly handle the default usage
of sg_write_same without the --xferlen parameter.
Reported-by: NEric Seppanen <eric@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@risingtidesystems.com>

This patch adds initial WRITE_SAME (10) w/ UNMAP=1 support following updates in
sbcr26 to allow UNMAP=1 for the non 16 + 32 byte CDB case.  It also refactors
current pSCSI passthrough passthrough checks into target_check_write_same_discard()
ahead of UNMAP=0 w/ write payload support into target_core_iblock.c.

This includes the support for handling WRITE_SAME in transport_emulate_control_cdb(),
and converts target_emulate_write_same to accept num_blocks directly for
WRITE_SAME, WRITE_SAME_16 and WRITE_SAME_32.
Reported-by: NEric Seppanen <eric@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@risingtidesystems.com>

This patch fixes a bug for fabrics using tfo->new_cmd_map() that
are expect transport_generic_request_failure() to be calling
transport_send_check_condition_and_sense() for both READ and WRITE,
instead of only for READ exceptions.

This was originally observed with a failed WRITE_SAME_16 w/ unmap=0
using tcm_loop.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a forever loop bug in iscsit_attach_ooo_cmdsn()
while walking sess->sess_ooo_cmdsn_list when the received
CmdSN is less than the tail of the list.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We returned on the line before already.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>