Add attribute 'transport_status' to simulate link failure.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: NHannes Reinecke <hare@suse.de>
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>

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>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This patch converts tcm_loop to use target_submit_cmd_map_sgls() for
I/O submission and mapping of pre-allocated SGL memory from incoming
scsi_cmnd -> se_cmd descriptors.

This includes removing the original open-coded fabric uses of target
core callers to support transport_generic_map_mem_to_cmd() between
target_setup_cmd_from_cdb() and transport_handle_cdb_direct() logic.

(v2: Use renamed target_submit_cmd_map_sgls)
Reported-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
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>

Just call target_execute_cmd directly.  Also, convert loopback, sbp,
usb-gadget to use the newly exported target_execute_cmd().
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We don't need three flags to classifiy the CDB as we can check for a NULL S/G
list for a dataless command, and can infer from the absence of the data flag
that we deal with a control CDB.  Also remove the _SG_IO from the data CDB
flag as all I/O is dont on S/G lists now.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch renames a horribly misnamed function that no longer allocate
tasks to something more descriptive for it's modern use in target core.

(nab: Fix up ib_srpt to use this as well ahead of a target_submit_cmd
conversion)
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses a tcm_loop bug with transport_generic_allocate_tasks()
return checking in tcm_loop_submission_work() where other non zero return
codes (including -EBUSY for reservation conflicts) are incorrectly falling
through to transport_generic_map_mem_to_cmd() -> transport_handle_cdb_direct().

This bug was introduced into target-pending/for-next-merge with the following
for-3.4 commit:

commit 16786454
Author: Christoph Hellwig <hch@infradead.org>
Date:   Thu Feb 2 17:04:42 2012 -0500

    tcm_loop: switch to using transport_handle_cdb_direct

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

Get rid of a bunch of write-only variables.  In a number of cases I
suspect actual bugs to be present, so I left all of those for a second
look.

(nab: fix lio-core patch fuzz)
Signed-off-by: NJoern Engel <joern@logfs.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch drops the following unused legacy API callers from target_core_fabric.h:

*) TFO->fall_back_to_erl0()
*) TFO->stop_session()
*) TFO->sess_logged_in()
*) TFO->is_state_remove()

This patch also removes the stub usage in loopback, tcm_fc, iscsi_target,
and ib_srpt fabric modules.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

If the target core signals an over- or under-run, tcm_loop should call
scsi_set_resid() to tell the SCSI midlayer about the residual data length.

The difference can be seen by doing something like

    strace -eioctl sg_raw -r 1024 /dev/sda 8 0 0 0 1 0 > /dev/null

and looking at the "resid=" part of the SG_IO ioctl -- after this patch,
the field is correctly reported as 512.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Now that we use a workqueue for I/O submission there is no need to use
transport_generic_handle_cdb_map any more.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Apply the qla2xxx model of submitting all commands from a workqueue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This function makes little sense as a separate abstraction as it's deeply
interwinded with the control flow of its only caller.  Merged it into
tcm_loop_queuecommand after factoring out a helper to convert the task
attribute representation.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Change the test for if a cmd is a tmr request to checking if
SCF_SCSI_TMR_CDB (a new flag) is set in cmd->se_cmd_flags.

Also remove se_tmr_req_cache usage in favor of kzalloc usage,
and make core_tmr_alloc_req() return int + setup se_cmd->se_tmr_req
directly and fix up various fabric module usages

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

There is not reason to artifically limit max_sectors in tcm_loop, set
it to UINT_MAX to allow stressing the large I/O handling in the target
core using the loopback driver.  Also remove various superflous defines
hiding the values set in the host template.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

A reader should spend an extra moment whenever noticing a cast,
because either something special is going on that deserves extra
attention or, as is all too often the case, the code is wrong.

These casts, afaics, have all been useless.  They cast a foo* to a
foo*, cast a void* to the assigned type, cast a foo* to void*, before
assigning it to a void* variable, etc.

In a few cases I also removed an additional &...[0], which is equally
useless.

Lastly I added three FIXMEs where, to the best of my judgement, the
code appears to have a bug.  It would be good if someone could check
these.
Signed-off-by: NJoern Engel <joern@logfs.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This reorganized the headers under include/target into:

 - target_core_base.h stays as is with all target-wide data stuctures and defines
 - target_core_backend.h contains the whole interface to I/O backends
 - target_core_fabric.h contains the whole interface to fabric modules

Except for those only the various configfs macro headers stay around.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

And use a SCF_BIDI flag instead.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch removes config_item_name() informational usage of
TFO->free_wwn() treewide in loopback, tcm_fc, ib_srpt and
tcm_vhost module code.

Using v4 target_core_fabric_configfs.c logic, a fabric call for
config_item_name() in TFO->drop_wwn() context returns NULL as
target_fabric_drop_wwn() invoking config_item_put() ->
config_group_put() will release fabric_port->port_wwn.wwn_group
before the last config_item_put() -> TFO->drop_wwn() is
invoked.
Reported-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch removes legacy usage of PYX_TRANSPORT_* return codes in a number
of locations and addresses cases where transport_generic_request_failure()
was returning the incorrect sense upon CHECK_CONDITION status after the
v3.1 converson to use errno return codes.

This includes the conversion of transport_generic_request_failure() to
process cmd->scsi_sense_reason and handle extra TCM_RESERVATION_CONFLICT
before calling transport_send_check_condition_and_sense() to queue up
response status.  It also drops PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES legacy
usgae, and returns TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE w/ a response
for these cases.

transport_generic_allocate_tasks(), transport_generic_new_cmd(), backend
SCF_SCSI_DATA_SG_IO_CDB ->do_task(), and emulated ->execute_task() have
all been updated to set se_cmd->scsi_sense_reason and return errno codes
universally upon failure.  This includes cmd->scsi_sense_reason assignment
in target_core_alua.c, target_core_pr.c and target_core_cdb.c emulation code.

Finally it updates fabric modules to remove the legacy usage, and for
TFO->new_cmd_map() callers forwards return values outside of fabric code.
iscsi-target has also been updated to remove a handful of special cases
related to the cleanup and signaling QUEUE_FULL handling w/ ft_write_pending()

(v2: Drop extra SCF_SCSI_CDB_EXCEPTION check during failure from
     transport_generic_new_cmd, and re-add missing task->task_error_status
     assignment in transport_complete_task)

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

This patch converts target_core_fabric_ops->check_stop_free() usage in
transport_cmd_check_stop() and associated fabric module usage to
return '1' when the passed se_cmd has been released directly within
->check_stop_free(), or return '0' when the passed se_cmd has not
been released.

This addresses an issue where transport_cmd_finish_abort() ->
transport_cmd_check_stop_to_fabric() was leaking descriptors during
LUN_RESET for modules using ->check_stop_free(), but not directly
releasing se_cmd in all cases.

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

This patch addresses an issue with buggy userspace code sending I/O
via scsi-generic that does not explictly clear their associated read
buffers.  It adds an explict memset of the first SGL entry within
tcm_loop_new_cmd_map() for SCF_SCSI_CONTROL_SG_IO_CDB payloads that
are currently guaranteed to be a single SGL by target-core code.

This issue is a side effect of the v3.1-rc1 merge to remove the
extra memcpy between certain control CDB types using a contigious
+ cleared buffer in target-core, and performing a memcpy into the
SGL list within tcm_loop.

It was originally mainfesting itself by udev + scsi_id + scsi-generic
not properly setting up the expected /dev/disk/by-id/ symlinks because
the INQUIRY payload was containing extra bogus data preventing the
proper NAA IEEE WWN from being parsed by userspace.

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

This patch fixes a bug with tcm_loop where performing a scsi_host rescan was
causing an oops due to a received scsi_cmnd->device->id value not matching a
previously configured tcm_loop_tpg entry in tcm_loop_hba->tl_hba_tpgs[]
obtained from within tcm_loop_queuecommand() code.

This fix adds an explict check for tcm_loop_tpg->tl_hba in order to ensure
tcm_loop_make_naa_tpg() has already been invoked to initialize a given
tcm_loop_tpg entry, and also adds an explict clear of tcm_loop_tpg->tl_hba
from within the tcm_loop_drop_naa_tpg() release path.

This bug was manifesting itself with the following OOPs:

[176289.430909] BUG: unable to handle kernel NULL pointer dereference at 0000000000000090
[176289.431337] IP: [<ffffffffa0395617>] transport_processing_thread+0x1e3/0x794 [target_core_mod]
[176289.431399] PGD 22e9b067 PUD 23375067 PMD 0
[176289.431399] Oops: 0000 [#1] SMP
[176289.431815] CPU 1
[176289.431815] Modules linked in: tcm_loop target_core_stgt target_core_pscsi target_core_file target_core_iblock target_core_mod crc32c ib_cm ib_sa ib_mad ib_core qla2xxx scsi_tgt configfs fcoe libfcoe libfc scsi_transport_fc ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi sr_mod cdrom sd_mod ata_piix libata e1000 mptspi mptscsih mptbase [last unloaded: target_core_mod]
[176289.431815]
[176289.431815] Pid: 12339, comm: LIO_iblock Tainted: G        W   3.1.0-rc8+
[176289.431815] RIP: 0010:[<ffffffffa0395617>]  [<ffffffffa0395617>] transport_processing_thread+0x1e3/0x794 [target_core_mod]
[176289.431815] RSP: 0018:ffff880023bfbe10  EFLAGS: 00010283
[176289.431815] RAX: 0000000000000000 RBX: ffff88002d600040 RCX: ffff88002d600108
[176289.431815] RDX: ffff88000c9e50bc RSI: 0000000000000246 RDI: 0000000000000246
[176289.431815] RBP: ffff880023bfbee0 R08: ffff88002d600108 R09: 0000000000000000
[176289.431815] R10: ffff88002fc8cc80 R11: ffffffff81671b60 R12: ffff88002d600108
[176289.431815] R13: ffff88000c9e4f38 R14: ffff88000c9e50b8 R15: 0000000000000000
[176289.431815] FS:  0000000000000000(0000) GS:ffff88002fc80000(0000) knlGS:0000000000000000
[176289.431815] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[176289.431815] CR2: 0000000000000090 CR3: 000000002a33f000 CR4: 00000000000006e0
[176289.431815] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[176289.431815] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[176289.431815] Process LIO_iblock (pid: 12339, threadinfo ffff880023bfa000, task ffff88002a2e0000)
[176289.431815] Stack:
[176289.431815]  0000000000011280 0000000000000246 ffff88002a2e0000 ffff880023a58900
[176289.431815]  ffff880023bfbed0 ffff880023bfa000 ffff880023bfa000 ffff88000c9e50d0
[176289.431815]  ffff88000c9e50c0 ffff88000c9e50bc ffff880023bfa000 ffff880023bfbfd8
[176289.431815] Call Trace:
[176289.431815]  [<ffffffff81056657>] ? wake_up_bit+0x25/0x25
[176289.431815]  [<ffffffffa0395434>] ? transport_handle_cdb_direct+0x92/0x92 [target_core_mod]
[176289.431815]  [<ffffffff8105619a>] kthread+0x7d/0x85
[176289.431815]  [<ffffffff813cbcb4>] kernel_thread_helper+0x4/0x10
[176289.431815]  [<ffffffff8105611d>] ? kthread_worker_fn+0x16d/0x16d
[176289.431815]  [<ffffffff813cbcb0>] ? gs_change+0x13/0x13
[176289.431815] Code: 67 05 00 00 41 8b 84 24 4c ff ff ff ff c8 83 f8 11 0f 87 f0 04 00 00 89 c0 ff 24 c5 b0 c6 39 a0 0f 0b eb fe 48 8b 83 d8 00 00 00
[176289.431815] RIP  [<ffffffffa0395617>] transport_processing_thread+0x1e3/0x794 [target_core_mod]
[176289.431815]  RSP <ffff880023bfbe10>
[176289.431815] CR2: 0000000000000090
[176295.041004] ---[ end trace 85dc6865b23b8f3e ]---
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Testing in_interrupt() to know when sleeping is allowed is not really
reliable (since eg it won't be true if the caller is holding a spinlock).
Instead have the caller tell core_tmr_alloc_req() what GFP_xxx to use;
every caller except tcm_qla2xxx can use GFP_KERNEL.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
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>

This patch contains the squashed version of forth round series cleanups
from Andy and Christoph following the post heavy lifting in the preceeding:
'Eliminate usage of struct se_mem' and 'Make all control CDBs scatter-gather'
changes.  This also includes a conversion of target core and the v3.0
mainline fabric modules (loopback and tcm_fc) to use pr_debug and the
CONFIG_DYNAMIC_DEBUG infrastructure!

These have been squashed into this third and final round for v3.1.

target: Remove ifdeffed code in t_g_process_write
target: Remove direct ramdisk code
target: Rename task_sg_num to task_sg_nents
target: Remove custom debug macros for pr_debug. Use pr_err().
target: Remove custom debug macros in mainline fabrics
target: Set WSNZ=1 in block limits VPD. Abort if WRITE_SAME sectors = 0
target: Remove transport do_se_mem_map callback
target: Further simplify transport_free_pages
target: Redo task allocation return value handling
target: Remove extra parentheses
target: change alloc_task call to take *cdb, not *cmd

(nab: Fix bogus struct file assignments in fd_do_readv and fd_do_writev)
Signed-off-by: NAndy Grover <agrover@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Both backstores and fabrics use arrays of struct scatterlist to describe
data buffers. However TCM used struct se_mems, basically a linked list
of scatterlist entries. We are able to simplify the code by eliminating
this intermediate data structure and just using struct scatterlist[]
throughout.

Also, moved attachment of task to cmd out of transport_generic_get_task
and into allocate_control_task and allocate_data_tasks. The reasoning
is that it's nonintuitive that get_task should automatically add it to
the cmd's task list -- it should just return an allocated, initialized
task. That's all it should do, based on the function's name, so either the
function shouldn't do it, or the name should change to encapsulate the
entire essence of what it does.

(nab: Fix compile warnings in tcm_fc, and make transport_kmap_first_data_page
 honor sg->offset for SGLs from contigious memory with TCM_Loop, and
 fix control se_cmd descriptor memory leak)
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There is a memory leak in tcm_loop_make_scsi_hba().

If all the strstr() calls return NULL and we end up at return ERR_PTR(-EINVAL);
then we'll be leaking the memory previously allocated to tl_hba as
that variable goes out of scope.

This patch should fix the leak.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This is an off by one 'tgpt' check in tcm_loop_make_naa_tpg() that could result
in memory corruption.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>

The release_cmd_to_pool and release_cmd_direct methods are always the same.
Merge them into a single release_cmd method, and clean up the fallout.

(nab: fix breakage in transport_generic_free_cmd() parameter build breakage
 in drivers/target/tcm_fc/tfc_cmd.c)
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>

This patch contains a squashed version of third round series cleanups,
improvements ,and simplfications from Andy and Christoph ahead of the
heavy lifting between round 3 -> 4 for the target core SGL conversion.

This include cleanups to the main target I/O path and other miscellaneous
updates.

target: Replace custom sg<->buf functions with lib funcs
target: Simplify sector limiting code
target: get_cdb should never return NULL
target: Simplify transport_memcpy_se_mem_read_contig
target: Use assignment rather than increment for t_task_cdbs
target: Don't pass dma_size to generic_get_mem
target: Pass sg with type scatterlist in transport_map_sg_to_mem
target: Move task_sg_num next to task_sg in struct se_task
target: inline struct se_transport_task into struct se_cmd
target: Change name & semantics of transport_get_sectors()
target: Remove unused members of se_cmd
target: Rename se_cmd.t_task_cdbs to t_task_list_num
target: Fix some spelling
target: Remove unused var from transport_generic_do_tmr
target: map_sg_to_mem: return sg_count in return value
target/pscsi: Use min_t for sector limits
target/pscsi: Unused param for pscsi_get_bio()
target: Rename get_cdb_count to allocate_tasks
target: Make transport_generic_new_cmd() available for iscsi-target
target: Remove fabric callback to allocate iovecs
target: Fix transport_generic_new_cmd WRITE comment

(hch: Use __GFP_ZERO usage for alloc_pages() usage)
Signed-off-by: NAndy Grover <agrover@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch contains the squashed version of second round of target core
cleanups and simplifications and Andy and Co.   It also contains a handful
of fixes to address bugs the original series and other minor cleanups.

Here is the condensed shortlog:

target: Remove unneeded casts to void*
target: Rename get_lun_for_{cmd,tmr} to lookup_{cmd,tmr}_lun
target: Make t_task a member of se_cmd, not a pointer
target: Handle functions returning "-2"
target: Use cmd->se_dev over cmd->se_lun->lun_se_dev
target: Embed qr in struct se_cmd
target: Replace embedded struct se_queue_req with a list_head
target: Rename list_heads that are nodes in struct se_cmd to "*_node"
target: Fold transport_device_setup_cmd() into lookup_{tmr,cmd}_lun()
target: Make t_mem_list and t_mem_list_bidi members of t_task
target: Add comment & cleanup transport_map_sg_to_mem()
target: Remove unneeded checks in transport_free_pages()

(Roland: Fix se_queue_req removal leftovers OOPs)
(nab: Fix transport_lookup_tmr_lun failure case)
(nab: Fix list_empty(&cmd->t_task.t_mem_bidi_list) inversion bugs)
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>