Introduce the function get_unaligned_be24(). Use {get,put}_unaligned_be*()
where appropriate. This patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: David Disseldorp <ddiss@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds the missing target_complete_cmd() SCSI status
parameter change in target_xcopy_do_work(), that was originally
missing in commit 926317de.

It correctly propigates up the correct SCSI status during
EXTENDED_COPY exception cases, instead of always using the
hardcoded SAM_STAT_CHECK_CONDITION from original code.

This is required for ESX host environments that expect to
hit SAM_STAT_RESERVATION_CONFLICT for certain scenarios,
and SAM_STAT_CHECK_CONDITION results in non-retriable
status for these cases.
Reported-by: NNixon Vincent <nixon.vincent@calsoftinc.com>
Tested-by: NNixon Vincent <nixon.vincent@calsoftinc.com>
Cc: Nixon Vincent <nixon.vincent@calsoftinc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

SPC4r37 6.4.1 EXTENDED COPY(LID4) states (also applying to LID1 reqs):
  A parameter list length of zero specifies that the copy manager shall
  not transfer any data or alter any internal state, and this shall not
  be considered an error.

This behaviour can be tested using the libiscsi ExtendedCopy.ParamHdr
test.
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

Check for XCOPY header, CSCD descriptor and segment descriptor list
truncation, and respond accordingly.

SPC4r37 6.4.1 EXTENDED COPY(LID4) states (also applying to LID1 reqs):
  If the parameter list length causes truncation of the parameter list,
  then the copy manager shall transfer no data and shall terminate the
  EXTENDED COPY command with CHECK CONDITION status, with the sense key
  set to ILLEGAL REQUEST, and the additional sense code set to PARAMETER
  LIST LENGTH ERROR.

This behaviour can be tested using the libiscsi ExtendedCopy.ParamHdr
test.
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

The XCOPY specification in SPC4r37 states that the XCOPY source and
destination device(s) should be derived from the copy source and copy
destination (CSCD) descriptor IDs in the XCOPY segment descriptor.

The CSCD IDs are generally (for block -> block copies), indexes into
the corresponding CSCD descriptor list, e.g.
=================================
EXTENDED COPY Header
=================================
CSCD Descriptor List
- entry 0
  + LU ID <--------------<------------------\
- entry 1                                   |
  + LU ID <______________<_____________     |
=================================      |    |
Segment Descriptor List                |    |
- segment 0                            |    |
  + src CSCD ID = 0 --------->---------+----/
  + dest CSCD ID = 1 ___________>______|
  + len
  + src lba
  + dest lba
=================================

Currently LIO completely ignores the src and dest CSCD IDs in the
Segment Descriptor List, and instead assumes that the first entry in the
CSCD list corresponds to the source, and the second to the destination.

This commit removes this assumption, by ensuring that the Segment
Descriptor List is parsed prior to processing the CSCD Descriptor List.
CSCD Descriptor List processing is modified to compare the current list
index with the previously obtained src and dest CSCD IDs.

Additionally, XCOPY requests where the src and dest CSCD IDs refer to
the CSCD Descriptor List entry can now be successfully processed.

Fixes: cbf031f4 ("target: Add support for EXTENDED_COPY copy offload")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=191381Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

Ensure that the segment descriptor CSCD descriptor ID values correspond
to CSCD descriptor entries located in the XCOPY command parameter list.
SPC4r37 6.4.6.1 Table 150 specifies this range as 0000h to 07FFh, where
the CSCD descriptor location in the parameter list can be located via:
16 + (id * 32)
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
[ bvanassche: inserted "; " in the format string of an error message
  and also moved a "||" operator from the start of a line to the end
  of the previous line ]
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

target_xcopy_locate_se_dev_e4() is used to locate an se_dev, based on
the WWN provided with the XCOPY request. Remove a couple of unneeded
arguments, and rely on the caller for the src/dst test.
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

Use UNSUPPORTED TARGET DESCRIPTOR TYPE CODE and UNSUPPORTED SEGMENT
DESCRIPTOR TYPE CODE additional sense codes if a descriptor type in an
XCOPY request is not supported, as specified in spc4r37 6.4.5 and 6.4.6.
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

spc4r37 6.4.3.5 states:
  If the combined length of the CSCD descriptors and segment descriptors
  exceeds the allowed value, then the copy manager shall terminate the
  command with CHECK CONDITION status, with the sense key set to ILLEGAL
  REQUEST, and the additional sense code set to PARAMETER LIST LENGTH
  ERROR.

This functionality can be tested using the libiscsi
ExtendedCopy.DescrLimits test.
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

Check the length of the XCOPY request segment descriptor list against
the value advertised via the MAXIMUM SEGMENT DESCRIPTOR COUNT field in
the RECEIVE COPY OPERATING PARAMETERS response.

spc4r37 6.4.3.5 states:
  If the number of segment descriptors exceeds the allowed number, the
  copy manager shall terminate the command with CHECK CONDITION status,
  with the sense key set to ILLEGAL REQUEST, and the additional sense
  code set to TOO MANY SEGMENT DESCRIPTORS.

This functionality is testable using the libiscsi
ExtendedCopy.DescrLimits test.
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

spc4r37 6.4.3.4 states:
  If the number of CSCD descriptors exceeds the allowed number, the copy
  manager shall terminate the command with CHECK CONDITION status, with
  the sense key set to ILLEGAL REQUEST, and the additional sense code
  set to TOO MANY TARGET DESCRIPTORS.

LIO currently responds with INVALID FIELD IN PARAMETER LIST, which sees
it fail the libiscsi ExtendedCopy.DescrLimits test.
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>

Remove superfluous #include directives from the include/target/*.h
files. Add missing #include directives to other *.h and *.c files.
Use forward declarations for structures where possible. This
change reduces the build time for make M=drivers/target on my
laptop from 27.1s to 18.7s or by about 30%.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bryant G. Ly <bryantly@linux.vnet.ibm.com>

This patch addresses a bug where a local EXTENDED_COPY WRITE or READ
backend I/O request would always return SAM_STAT_CHECK_CONDITION,
even if underlying xcopy_pt_cmd->se_cmd generated a different
SCSI status code.

ESX host environments expect to hit SAM_STAT_RESERVATION_CONFLICT
for certain scenarios, and SAM_STAT_CHECK_CONDITION results in
non-retriable status for these cases.

Tested on v4.1.y with ESX v5.5u2+ with local IBLOCK backend copy.
Reported-by: NNixon Vincent <nixon.vincent@calsoftinc.com>
Tested-by: NNixon Vincent <nixon.vincent@calsoftinc.com>
Cc: Nixon Vincent <nixon.vincent@calsoftinc.com>
Tested-by: NDinesh Israni <ddi@datera.io>
Signed-off-by: NDinesh Israni <ddi@datera.io>
Cc: Dinesh Israni <ddi@datera.io>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses a bug where EXTENDED_COPY across multiple LUNs
results in a CHECK_CONDITION when the source + destination are not
located on the same physical node.

ESX Host environments expect sense COPY_ABORTED w/ COPY TARGET DEVICE
NOT REACHABLE to be returned when this occurs, in order to signal
fallback to local copy method.

As described in section 6.3.3 of spc4r22:

  "If it is not possible to complete processing of a segment because the
   copy manager is unable to establish communications with a copy target
   device, because the copy target device does not respond to INQUIRY,
   or because the data returned in response to INQUIRY indicates
   an unsupported logical unit, then the EXTENDED COPY command shall be
   terminated with CHECK CONDITION status, with the sense key set to
   COPY ABORTED, and the additional sense code set to COPY TARGET DEVICE
   NOT REACHABLE."

Tested on v4.1.y with ESX v5.5u2+ with BlockCopy across multiple nodes.
Reported-by: NNixon Vincent <nixon.vincent@calsoftinc.com>
Tested-by: NNixon Vincent <nixon.vincent@calsoftinc.com>
Cc: Nixon Vincent <nixon.vincent@calsoftinc.com>
Tested-by: NDinesh Israni <ddi@datera.io>
Signed-off-by: NDinesh Israni <ddi@datera.io>
Cc: Dinesh Israni <ddi@datera.io>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The SRP target driver will need to allocate and chain it's own SGLs soon.
For this export target_alloc_sgl, and add a new argument to it so that it
can allocate an additional chain entry that doesn't point to a page.  Also
export transport_free_sgl after renaming it to target_free_sgl to free
these SGLs again.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch is a >= v4.1 regression bug-fix where control CDB
emulation logic in commit 38b57f82 now expects a se_cmd->se_sess
pointer to exist when determining T10-PI support is to be exposed
for initiator host ports.

To address this bug, go ahead and add locally generated se_cmd
descriptors for copy-offload block-copy to it's own stand-alone
se_session nexus, while the parent EXTENDED_COPY se_cmd descriptor
remains associated with it's originating se_cmd->se_sess nexus.

Note a valid se_cmd->se_sess is also required for future support
of WRITE_INSERT and READ_STRIP software emulation when submitting
backend I/O to se_device that exposes T10-PI suport.
Reported-by: NAlex Gorbachev <ag@iss-integration.com>
Tested-by: NAlex Gorbachev <ag@iss-integration.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: <stable@vger.kernel.org> # v4.1+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Only include SCSI initiator header files in target code that needs
these header files, namely the SCSI pass-through code and the tcm_loop
driver. Change SCSI_SENSE_BUFFERSIZE into TRANSPORT_SENSE_BUFFER in
target code because the former is intended for initiator code and the
latter for target code. With this patch the only initiator include
directives in target code that remain are as follows:

$ git grep -nHE 'include .scsi/(scsi.h|scsi_host.h|scsi_device.h|scsi_cmnd.h)' drivers/target drivers/infiniband/ulp/{isert,srpt} drivers/usb/gadget/legacy/tcm_*.[ch] drivers/{vhost,xen} include/{target,trace/events/target.h}
drivers/target/loopback/tcm_loop.c:29:#include <scsi/scsi.h>
drivers/target/loopback/tcm_loop.c:31:#include <scsi/scsi_host.h>
drivers/target/loopback/tcm_loop.c:32:#include <scsi/scsi_device.h>
drivers/target/loopback/tcm_loop.c:33:#include <scsi/scsi_cmnd.h>
drivers/target/target_core_pscsi.c:39:#include <scsi/scsi_device.h>
drivers/target/target_core_pscsi.c:40:#include <scsi/scsi_host.h>
drivers/xen/xen-scsiback.c:52:#include <scsi/scsi_host.h> /* SG_ALL */
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <JBottomley@Odin.com>

This patch eliminates all se_port + t10_alua_tg_pt_gp_member usage,
and converts current users to direct se_lun pointer dereference.

This includes the removal of core_export_port(), core_release_port()
core_dev_export() and core_dev_unexport().  Along with conversion
of special case se_lun pointer dereference within PR ALL_TG_PT=1
and ALUA access state transition UNIT_ATTENTION handling.

Also, update core_enable_device_list_for_node() to reference the
new per se_lun->lun_deve_list when creating a new entry, or
replacing an existing one via RCU.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.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>

Simplify target core and target drivers by storing the task tag
a.k.a. command identifier inside struct se_cmd.

For several transports (e.g. SRP) tags are 64 bits wide.
Hence add support for 64-bit tags.

(Fix core_tmr_abort_task conversion spec warnings - nab)
(Fix up usb-gadget to use 16-bit tags - HCH + bart)
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: <qla2xxx-upstream@qlogic.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Juergen Gross <jgross@suse.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>

Drop unused argument & return value and consolidate a duplicate assignment.
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>

We should not declare extrnal .c symbols in C files to make sure they
match the actual prototype, and sparse correctly warns about this.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fix spelling typo in printk and Kconfig within
various part of kernel sources.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Convert "x == true" to "x" and "x == false" to "!x".
Signed-off-by: NChristophe Vu-Brugier <cvubrugier@yahoo.fr>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Move prototype declaration of function
spc_parse_naa_6h_vendor_specific() from target_core_xcopy.c to header
file target_core_pr.h because it is used by more than one file.

This eliminates the following warning in target_core_spc.c:
drivers/target/target_core_spc.c:138:6: warning: no previous prototype for ‘spc_parse_naa_6h_vendor_specific’ [-Wmissing-prototypes]
Signed-off-by: NRashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds a se_device->xcopy_lun that is used for local
copy offload I/O, instead of allocating + initializing a pseudo
se_lun for each received EXTENDED_COPY operation.

Also, move declaration of struct se_lun + struct se_port_stat_grps
ahead of struct se_device.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Now with percpu refcounting for se_lun in place, go ahead and drop
the legacy per se_cmd accounting for se_lun shutdown.

This includes __transport_clear_lun_from_sessions(), the associated
transport_lun_wait_for_tasks() logic, along with a handful of now
unused se_cmd structure members and ->transport_state bits.

Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds percpu refcounting for se_lun access that allows the
association of an se_lun + se_cmd in transport_lookup_cmd_lun() to
occur without an extra list_head for tracking outstanding I/O during
se_lun shutdown.

This effectively changes se_lun shutdown logic to wait for outstanding
I/O percpu references to complete in transport_lun_remove_cmd() using
se_lun->lun_ref_comp, instead of explicitly draining the per se_lun
command list and waiting for individual se_cmd descriptor processing
to complete.

Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds an explicit check + failure for XCOPY I/O to source +
destination devices with a non-matching block_size.

This limitiation is currently due to the fact that the scatterlist
memory allocated for the XCOPY READ operation is passed zero-copy
to the XCOPY WRITE operation.
Reported-by: NThomas Glanzmann <thomas@glanzmann.de>
Reported-by: NDouglas Gilbert <dgilbert@interlog.com>
Cc: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds the missing non-zero se_cmd->scsi_status check required
for local XCOPY I/O within target_xcopy_issue_pt_cmd() to signal an
exception case failure.

This will trigger the generation of SAM_STAT_CHECK_CONDITION status
from within target_xcopy_do_work() process context code.
Reported-by: NThomas Glanzmann <thomas@glanzmann.de>
Reported-by: NDouglas Gilbert <dgilbert@interlog.com>
Cc: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds the missing xcopy_pt_cmd->sense_buffer[] required for
correctly handling CHECK_CONDITION exceptions within the locally
generated XCOPY I/O path.

Also update target_xcopy_read_source() + target_xcopy_setup_pt_cmd()
to pass this buffer into transport_init_se_cmd() to correctly setup
se_cmd->sense_buffer.
Reported-by: NThomas Glanzmann <thomas@glanzmann.de>
Reported-by: NDouglas Gilbert <dgilbert@interlog.com>
Cc: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch rejects EXTENDED_COPY when the emulate_3pc attribute has
been explicitly disabled for the receiving device.

It also adds a similar check in target_xcopy_locate_se_dev_e4() to
ignore these devices when doing a search based upon the identifier
WWN provided by EXTENDED_COPY parameter list target descriptors.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch changes target_do_xcopy() to allow processing of non-zero
ListIDs in EXTENDED_COPY parameter list data, instead of returning
CHECK_CONDITION status.

As the copy offload implementation reports SNLID=1 (Supports No ListID)
in OPERATING PARAMETERS, any ListID value presented by the client is
currently ignored.

Also, properly extract list_id_usage for informational purposes.
Reported-by: NThomas Glanzmann <thomas@glanzmann.de>
Reported-by: NDouglas Gilbert <dgilbert@interlog.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch changes target_do_xcopy() to properly return
TCM_INVALID_PARAMETER_LIST instead of TCM_INVALID_CDB_FIELD
for failures related to the EXTENDED_COPY parameter list parsing.

Also, move struct xcopy_op allocation ahead of kmapping to
handle the special TCM_OUT_OF_RESOURCES case.
Reported-by: NThomas Glanzmann <thomas@glanzmann.de>
Reported-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes up an incorrect assignment for xop->dbl within
target_xcopy_parse_segdesc_02() code, as reported by Coverity here:

http://marc.info/?l=linux-kernel&m=137936416618490&w=2Reported-by: NDave Jones <davej@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Remove including <linux/version.h> that don't need it.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds support for EXTENDED_COPY emulation from SPC-3, that
enables full copy offload target support within both a single virtual
backend device, and across multiple virtual backend devices.  It also
functions independent of target fabric, and supports copy offload
across multiple target fabric ports.

This implemenation supports both EXTENDED_COPY PUSH and PULL models
of operation, so the actual CDB may be received on either source or
desination logical unit.

For Target Descriptors, it currently supports the NAA IEEE Registered
Extended designator (type 0xe4), which allows the reference of target
ports to occur independent of fabric type using EVPD 0x83 WWNs.

For Segment Descriptors, it currently supports copy from block to
block (0x02) mode.

It also honors any present SCSI reservations of the destination target
port.  Note that only Supports No List Identifier (SNLID=1) mode is
supported.

Also included is basic RECEIVE_COPY_RESULTS with service action type
OPERATING PARAMETERS (0x03) required for SNLID=1 operation.

v3 changes:
  - Fix incorrect return type in target_do_receive_copy_results()
    (Fengguang)

v2 changes:
  - Use target_alloc_sgl() instead of transport_generic_get_mem()
  - Convert debug output to use pr_debug()
  - Convert target_xcopy_parse_target_descriptors() NAA IEEN WWN
    dump to use 0x%16phN format specification
  - Drop unnecessary xcopy_pt_cmd->xpt_passthrough_wsem, and
    associated usage in xcopy_pt_write_pending() and
    target_xcopy_issue_pt_cmd()
  - Add check for unsupported EXTENDED_COPY(LID4) service action
    bits in target_do_xcopy()

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Zach Brown <zab@redhat.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: NNicholas Bellinger <nab@daterainc.com>