This patch changes iscsit_sequence_cmd() logic to no longer reject
non-immediate CmdSNs that exceed MaxCmdSN with a protocol error,
but instead silently ignore them.

This is done to correctly follow RFC-3720 Section 3.2.2.1:

   For non-immediate commands, the CmdSN field can take any
   value from ExpCmdSN to MaxCmdSN inclusive.  The target MUST silently
   ignore any non-immediate command outside of this range or non-
   immediate duplicates within the range.
Reported-by: NSantosh Kulkarni <santosh.kulkarni@calsoftinc.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch converts a handful of iscsi_session statistics to type
atomic_long_t, instead of using iscsi_session->session_stats_lock
when incrementing these values.

More importantly, go ahead and drop the spinlock usage within
iscsit_setup_scsi_cmd(), iscsit_check_dataout_hdr(),
iscsit_send_datain(), and iscsit_build_rsp_pdu() fast-path code.

(Squash in Roland's  target: Remove write-only stats fields and lock
from struct se_node_acl)
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch converts the handful of se_device statistics to type
atomic_long_t, instead of using se_device->stats_lock when
incrementing these values.

More importantly, go ahead and drop the spinlock usage within
transport_lookup_cmd_lun() fast-path code.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a bug in delayed Task Aborted Status (TAS) handling,
where transport_send_task_abort() was not returning for the case
when the se_tfo->write_pending() callback indicated that last fabric
specific WRITE PDU had not yet been received.

It also adds an explicit cmd->scsi_status = SAM_STAT_TASK_ABORTED
assignment within transport_check_aborted_status() to avoid the case
where se_tfo->queue_status() is called when the SAM_STAT_TASK_ABORTED
assignment + ->queue_status() in transport_send_task_abort() does not
occur once SCF_SENT_DELAYED_TAS has been set.

Cc: <stable@vger.kernel.org> #3.2+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds a check to reject text commands with F_BIT=0 ||
C_BIT=1, as multi PDU text command sequences are currently
unsupported.

This avoids the case where a text command received with F_BIT=0,
was generating a text response with F_BIT=1 which is a protocol
error according to RFC-3720 Section 10.11.1.
Reported-by: NArshad Hussain <arshad.hussain@calsoftinc.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a >= v3.10 regression bug with mutex_trylock() usage
within iscsit_increment_maxcmdsn(), that was originally added to allow
for a special case where ->cmdsn_mutex was already held from the
iscsit_execute_cmd() exception path for ib_isert.

When !mutex_trylock() was occuring under contention during normal RX/TX
process context codepaths, the bug was manifesting itself as the following
protocol error:

  Received CmdSN: 0x000fcbb7 is greater than MaxCmdSN: 0x000fcbb6, protocol error.
  Received CmdSN: 0x000fcbb8 is greater than MaxCmdSN: 0x000fcbb6, protocol error.

This patch simply avoids the direct ib_isert callback in lio_queue_status()
for the special iscsi_execute_cmd() exception cases, that allows the problematic
mutex_trylock() usage in iscsit_increment_maxcmdsn() to go away.
Reported-by: NMoussa Ba <moussaba@micron.com>
Tested-by: NMoussa Ba <moussaba@micron.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Target core does not depend on the block layer, only backstores that
use the block layer do.
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In addition to block size (already implemented), passing through
alignment offset, logical-to-phys block exponent, I/O granularity and
optimal I/O length will allow initiators to properly handle layout on
LUNs with 4K block sizes.

Tested with various weird values via scsi_debug module.

One thing to look at with this patch is the new block limits values --
instead of granularity 1 optimal 8192, Lio will now be returning whatever
the block device says, which may affect performance.
Signed-off-by: NAndy Grover <agrover@redhat.com>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
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 changes iscsit_check_dataout_hdr() to no longer generate
REJECTs for zero-length DataOUTs, and instead simply ignore these
requests.

This follows RFC-3720, Section 10.7.7.  DataSegmentLength

  "This is the data payload length of a SCSI Data-In or SCSI Data-Out PDU.
   The sending of 0 length data segments should be avoided, but initiators
   and targets MUST be able to properly receive 0 length data segments."
Reported-by: NSantosh Kulkarni <santosh.kulkarni@calsoftinc.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

If demo_mode_discovery=0 and generate_node_acls=0 (demo mode dislabed) do
not return TargetName+TargetAddress unless a NodeACL exists.
Signed-off-by: NThomas Glanzmann <thomas@glanzmann.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Export symbol core_tpg_check_initiator_node_acl and move prototype from the
private drivers/target/target_core_internal.h to the public
include/target/target_core_fabric.h
Signed-off-by: NThomas Glanzmann <thomas@glanzmann.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Add a new TPG attribute demo_mode_discovery which is enabled by default.
Signed-off-by: NThomas Glanzmann <thomas@glanzmann.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Implement target reset by resetting the transport status.

(nab: Remove unused ret in tcm_loop_target_reset)
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Implement TCQ support, which enables us to do proper command
abort, too.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

No functional change.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

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>

These just want to return a pointer instead of a value, but are otherwise
the same.

ISCSI_TPG_LUN macro was unused.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

These are all straightforward.
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>

This patch converts tcm_fc to use transport_init_session_tags()
pre-allocation logic for struct ft_cmd descriptors using per-cpu
session tag pooling in order to effectively avoid memory allocation
+ release for each received I/O.

It adds percpu_ida_alloc() in ft_recv_cmd() to obtain an tag and
locate ft_cmd from se_sess->sess_cmd_map[], and percpu_ida_free()
in ft_free_cmd() to release the tag based upon se_cmd->map_tag id.

It also uses a TCM_FC_DEFAULT_TAGS value of 512, that puts the
per se_sess->sess_cmd_map allocation at ~360K on 64-bit.

v2 changes:

  - Handle possible tag < 0 failure with GFP_ATOMIC

Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Robert Love <robert.w.love@intel.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: NNicholas Bellinger <nab@daterainc.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>

This patch bumps the default TCP listen backlog within iscsit_setup_np()
from 5 to 256, in order to reduce the overall latency caused by a small
backlog with 100's of simultaneous login attempts directed to the same
single network portal.

Also add a ISCSIT_TCP_BACKLOG macro in iscsi_target_core.h.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a >= v3.9+ regression in __core_scsi3_write_aptpl_to_file()
+ core_alua_write_tpg_metadata() write-out, where a return value of -EIO was
incorrectly being returned upon success.

This bug was originally introduced in:

commit 0e9b10a9
Author: Al Viro <viro@zeniv.linux.org.uk>
Date:   Sat Feb 23 15:22:43 2013 -0500

    target: writev() on single-element vector is pointless

However, given that the return of core_scsi3_update_and_write_aptpl()
was not used to determine if a command should be returned with non GOOD
status, this bug was not being triggered in PR logic until v3.11-rc1 by
commit:

commit 459f213b
Author: Andy Grover <agrover@redhat.com>
Date:   Thu May 16 10:41:02 2013 -0700

    target: Allocate aptpl_buf inside update_and_write_aptpl()

So, go ahead and only return -EIO if kernel_write() returned a
negative value.
Reported-by: NGera Kazakov <gkazakov@msn.com>
Signed-off-by: NGera Kazakov <gkazakov@msn.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@vger.kernel.org # 3.9+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch bumps the default TA_DEFAULT_CMDSN_DEPTH from 16 -> 64,
which is closer to a sane default for larger pipes @ 10 Gb/sec
with traditional iSCSI, or @ 40/56 Gb/sec Ethernet/Infiniband with
iSCSI Extentions for RDMA.

There is really no downside to increasing this default value for
1 Gb/sec.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch removes an unnecessary wait_for_completion within
iscsi_get_thread_set(), that would wait for 1 second before
trying to obtain an inactive struct iscsi_thread_set from
iscsi_get_ts_from_inactive_list().

Since iscsi_allocate_thread_sets() will already be adding the
newly allocated iscsi_thread_set to the inactive list directly,
there is no need to wait here.
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch removes the iscsi_thread_set->[rx,tx]_post_start_comp that
was originally used synchronize startup between rx and tx threads within
a single thread_set.

Instead, use a single ->ts_activate_sem in iscsi_activate_thread_set()
to wait for both processes to awake in the RX/TX pre handlers.

Also, go ahead and refactor thread_set deallocate code into a common
iscsi_deallocate_thread_one(), and update iscsi_deallocate_thread_sets()
and iscsi_deallocate_extra_thread_sets() use this code

v3 changes:
  - Make iscsi_deallocate_thread_one defined as static (Fengguang)

v2 changes:
  - Set ISCSI_THREAD_SET_ACTIVE before calling complete in
    iscsi_activate_thread_set
  - Protect ts->conn sanity checks with ->ts_state_lock in
    RX/TX pre handlers
  - Add ->ts_activate_sem to save extra context switches per
    iscsi_activate_thread_set() call.
  - Refactor thread_set shutdown into iscsi_deallocate_thread_one()
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses an long standing race in iscsi_[rx,tx]_thread_pre_handler()
use of flush_signals(), and between iscsi_deallocate_extra_thread_sets() setting
ISCSI_THREAD_SET_DIE before calling kthread_stop().

It addresses the issue by both holding ts_state_lock before calling send_sig()
in iscsi_deallocate_extra_thread_sets(), as well as only calling flush_signals()
when ts->status != ISCSI_THREAD_SET_DIE within iscsi_[rx,tx]_thread_pre_handler()
code.

v2 changes:
  - Add explicit complete(&ts->[rx,tx]_start_comp); before kthread_stop() in
    iscsi_deallocate_extra_thread_sets()
  - Drop left-over send_sig() calls in iscsi_deallocate_extra_thread_sets()
  - Add kthread_should_stop() check in iscsi_signal_thread_pre_handler()
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>

Add calls to target_xcopy_setup_pt() + target_xcopy_release_pt() to
target_core_init_configfs() and target_core_exit_configfs()
respectively.

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>

This patch adds the Third Party Copy (3PC) bit to signal support
for EXTENDED_COPY within standard inquiry response data.

Also add emulate_3pc device attribute in configfs (enabled by default)
to allow the exposure of this bit to be disabled, if necessary.

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>

Setup up the se_cmd->execute_cmd() pointers for EXTENDED_COPY and
RECEIVE_COPY_RESULTS handling within spc_parse_cdb()

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>

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>

This patch adds an check for a non-existent port->sep_alua_tg_pt_gp_mem
within target_alua_state_check(), which is not present for internally
dispatched EXTENDED_COPY WRITE I/O to the destination target port.

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>

EXTENDED_COPY needs to be able to search a global list of devices
based on NAA WWN device identifiers, so add a simple g_device_list
protected by g_device_mutex.

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>

Both target_alloc_sgl() and transport_generic_map_mem_to_cmd() are
required by EXTENDED_COPY logic when setting up internally dispatched
command descriptors, so go ahead and make both of these non static.

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>