extract_param() is called with max_length set to the total size of the
output buffer.  It's not safe to allow a parameter length equal to the
buffer size as the terminating null would be written one byte past the
end of the output buffer.
Signed-off-by: NEric Seppanen <eric@purestorage.com>
Cc: <stable@vger.kernel.org> #3.1+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch exposes default_erl as a TPG attribute so that it may be
set TPG wide in demo-mode, but still allow the existing NodeACL
attribute to be overridden on a per initiator basis.
Reported-by: NArshad Hussain <arshad.hussain@calsoftinc.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Split up the various ALUA states into individual attributes to
make parsing easier and adhere to the one value per attribute
sysfs principle.

(nab: Convert strict_strtoul -> kstrtoul usage)
Signed-off-by: NHannes Reinecke <hare@suse.de>

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

The supported ALUA states might be different for individual
devices, so store it in a separate field.

(nab: Remove unnecessary line continuation)
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Rename ALUA_ACCESS_STATE_OPTMIZED to
ALUA_ACCESS_STATE_OPTIMIZED.
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>

Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Drop percpu_ida.o from lib-y since it is also listed in obj-y
and it doesn't need to be listed in both places.

Move percpu-refcount.o from lib-y to obj-y to fix build errors
in target_core_mod:

ERROR: "percpu_ref_cancel_init" [drivers/target/target_core_mod.ko] undefined!
ERROR: "percpu_ref_kill_and_confirm" [drivers/target/target_core_mod.ko] undefined!
ERROR: "percpu_ref_init" [drivers/target/target_core_mod.ko] undefined!
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

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 avoids a duplicate iscsit_increment_maxcmdsn() call for
ISER_IB_RDMA_WRITE within isert_map_rdma() + isert_reg_rdma_frwr(),
which will already be occuring once during isert_put_datain() ->
iscsit_build_rsp_pdu() operation.

It also removes the local conn->stat_sn assignment + increment,
and changes the third parameter to iscsit_build_rsp_pdu() to
signal this should be done by iscsi_target_mode code.
Tested-by: NMoussa Ba <moussaba@micron.com>
Cc: <stable@vger.kernel.org> # v3.10+
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 changes isert_reg_rdma_frwr() to not use FRMR for single
dma entry requests from small I/Os, in order to avoid the associated
memory registration overhead.

Using DMA MR is sufficient here for the single dma entry requests,
and addresses a >= v3.12 performance regression.
Signed-off-by: NVu Pham <vu@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.12+
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 EXPORT_SYMBOL() for percpu_ref_init(),
percpu_ref_cancel_init() and percpu_ref_kill_and_confirm() so
that percpu refcounting can be used by external modules.

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>

This patch adds support for completion interrupt coalescing that
allows only every ISERT_COMP_BATCH_COUNT (8) to set IB_SEND_SIGNALED,
thus avoiding completion interrupts for every posted iser_tx_desc.

The batch processing is done using a per isert_conn llist that once
IB_SEND_SIGNALED has been set is saved to tx_desc->comp_llnode_batch,
and completion processing of previously posted iser_tx_descs is done
in a single shot from within isert_send_completion() code.

Note this is only done for response PDUs from ISCSI_OP_SCSI_CMD, and
all other control type of PDU responses will force an implicit batch
drain to occur.

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Roland Dreier <roland@purestorage.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>

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>

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>

Removing unused struct percpu_ida *pool from arguements of
alloc_local_tag, changed it's one use in percpu_ida.c

(nab: Fixed reference of idr.c -> percpu_ida.c)
Signed-Off-By: NNick Swenson <nks@daterainc.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>