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 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>

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>

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>

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>

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 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>

This patch changes iscsi-target to use transport_alloc_session_tags()
pre-allocation logic for per-cpu session tag pooling with internal
ida_alloc() + ida_free() calls based upon the saved se_cmd->map_tag id.

This includes tag pool setup based upon per NodeACL queue_depth after
locating se_node_acl in iscsi_target_locate_portal().

Also update iscsit_allocate_cmd() and iscsit_release_cmd() to use
percpu_ida_alloc() and percpu_ida_free() respectively.

v5 changes;
  - Convert to percpu_ida.h include

v2 changes:
  - Fix bug with SessionType=Discovery in iscsi_target_locate_portal()

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: NNicholas Bellinger <nab@daterainc.com>

This command converts iscsi/isert-target to use allocations based on
iscsit_transport->priv_size within iscsit_allocate_cmd(), instead of
using an embedded isert_cmd->iscsi_cmd.

This includes removing iscsit_transport->alloc_cmd() usage, along
with updating isert-target code to use iscsit_priv_cmd().

Also, remove left-over iscsit_transport->release_cmd() usage for
direct calls to iscsit_release_cmd(), and drop the now unused
lio_cmd_cache and isert_cmd_cache.

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: NNicholas Bellinger <nab@daterainc.com>

There is no need for iscsi_target_do_login_io() anymore in modern code,
so go ahead and call iscsi_target_do_tx_login_io() directly within
iscsi_target_do_login().
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds a sock->sk_state_change() -> iscsi_target_sk_state_change()
callback in order to handle transient TCP failures during the login process,
where sock->sk_data_ready() -> iscsi_target_sk_data_ready() may not be
called to release connection resources, and relinquish tpg->np_login_lock
via iscsit_deaccess_np()

It performs the sk->sk_state check using iscsi_target_sk_state_check() to
look for TCP_CLOSE_WAIT + TCP_CLOSE, and invokes schedule_delayed_work() ->
iscsi_target_do_cleanup() to perform the remaining cleanup from process
context.

It adds an explicit sk_state_check to iscsi_target_do_login() in order
to determine a state failure when iscsi_target_sk_state_change() may
not be able to proceed before LOGIN_FLAGS_READY=1 is set.

Also use sk->sk_sndtimeo -> sk->sk_rcvtimeo settings during login to
iscsi_target_set_sock_callbacks(), and revert back post login to use
MAX_SCHEDULE_TIMEOUT in iscsi_target_restore_sock_callbacks().
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds support for login negotiation multi-plexing in
iscsi-target code.

This involves handling the first login request PDU + payload and
login response PDU + payload within __iscsi_target_login_thread()
process context, and then changing struct sock->sk_data_ready()
so that all subsequent exchanges are handled by workqueue process
context, to allow other incoming login requests to be received
in parallel by __iscsi_target_login_thread().

Upon login negotiation completion (or failure), ->sk_data_ready()
is replaced with the original kernel sockets handler saved in
iscsi_conn->orig_data_ready.

v3 changes:
  - Convert iscsi_target_sk_data_ready() lock access to
    write[lock,unlock]_bh()
  - Only clear LOGIN_FLAGS_READ_ACTIVE when iscsi_target_do_login()
    returns zero
  - Add LOGIN_FLAGS_READY + LOGIN_FLAGS_CLOSED bit checks to
    iscsi_target_sk_data_ready()
  - Make INIT_DELAYED_WORK() + iscsi_target_set_sock_callbacks() setup
    happen earlier by moving from iscsi_target_start_negotiation() into
    iscsi_target_locate_portal()
  - Set LOGIN_FLAGS_READY bit in iscsi_target_start_negotiation()
    after iscsi_target_do_login() returns zero.

v2 changes:
  - Add login_timer in iscsi_target_do_login_rx() to avoid
    possible endless sleep with MSG_WAITALL for traditional
    iscsi-target in certain network configurations.
  - Convert lprintk() -> pr_debug()
  - Remove forward declarations of iscsi_target_set_sock_callbacks(),
    iscsi_target_restore_sock_callbacks() and iscsi_target_sk_data_ready()
  - Make iscsi_target_set_sock_callbacks + iscsi_target_restore_sock_callbacks()
    static (Fengguang)
  - Make iscsi_target_do_login_rx() safe for iser-target w/o conn->sock
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch prepares the iscsi-target login code for multi-plexing
support.  This includes:

 - Adding iscsi_tpg_np->tpg_np_kref + iscsit_login_kref_put() for
   handling callback of iscsi_tpg_np->tpg_np_comp
 - Adding kref_put() in iscsit_deaccess_np()
 - Adding kref_put() and wait_for_completion() in
   iscsit_reset_np_thread()
 - Refactor login failure path release logic into
   iscsi_target_login_sess_out()
 - Update __iscsi_target_login_thread() to handle
   iscsi_post_login_handler() asynchronous completion
 - Add shutdown parameter for iscsit_clear_tpg_np_login_thread*()

v3 changes:
 - Convert iscsi_portal_group->np_login_lock to ->np_login_sem
 - Add LOGIN_FLAGS definitions

v2 changes:
 - Remove duplicate call to iscsi_post_login_handler() in
   __iscsi_target_login_thread()
 - Drop unused iscsi_np->np_login_tpg
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses a potential NULL pointer dereference regression in
iscsit_setup_nop_out() code, specifically for two cases when a solicited
NOPOUT triggers a ISCSI_REASON_PROTOCOL_ERROR reject to be generated.

This is because iscsi_cmd is expected to be NULL for solicited NOPOUT
case before iscsit_process_nop_out() locates the descriptor via TTT
using iscsit_find_cmd_from_ttt().

This regression was originally introduced in:

commit ba159914
Author: Nicholas Bellinger <nab@linux-iscsi.org>
Date:   Wed Jul 3 03:48:24 2013 -0700

    iscsi-target: Fix iscsit_add_reject* usage for iser

Cc: stable@vger.kernel.org  # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a bug in __iscsi_target_login_thread() where an explicit
network portal thread reset ends up leaking the iscsit_transport module
reference, along with the associated iscsi_conn allocation.

This manifests itself with iser-target where a NP reset causes the extra
iscsit_transport reference to be taken in iscsit_conn_set_transport()
during the reset, which prevents the ib_isert module from being unloaded
after the NP thread shutdown has finished.

Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses a regression bug within ImmediateData=Yes failure
handling that ends up triggering an OOPs within >= v3.10 iscsi-target
code.

The problem occurs when iscsit_process_scsi_cmd() does the call to
target_put_sess_cmd(), and once again in iscsit_get_immediate_data()
that is triggered during two different cases:

 - When iscsit_sequence_cmd() returns CMDSN_LOWER_THAN_EXP, for which
   the descriptor state will already have been set to ISTATE_REMOVE
   by iscsit_sequence_cmd(), and
 - When iscsi_cmd->sense_reason is set, for which iscsit_execute_cmd()
   will have already called transport_send_check_condition_and_sense()
   to queue the exception response.

It changes iscsit_process_scsi_cmd() to drop the early call, and makes
iscsit_get_immediate_data() call target_put_sess_cmd() from a single
location after dumping the immediate data for the failed command.

The regression was initially introduced in commit:

commit 561bf158
Author: Nicholas Bellinger <nab@linux-iscsi.org>
Date:   Wed Jul 3 03:58:58 2013 -0700

    iscsi-target: Fix iscsit_sequence_cmd reject handling for iser

Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Odd little issue, found that if you create an IPv6 portal bound to the
IN6ADDR_ANY wildcard address it will accept IPv4 connections (as long as
bindv6only isn't set globally) but respond to SendTargets requests with
an IPv4-mapped IPv6 address.

Example over loopback:

 In targetcli create a wildcard IPv6 portal
   /iscsi/iqn.../portals/> create ::
 Which should create a portal [::]:3260

 Initiate SendTargets discovery to the portal using an IPv4 address
   # iscsiadm -m discovery -t st -p 127.0.0.1
 The response formats TargetAddress as [::ffff:127.0.0.1]:3260,1

This still works and uses v4 on the network between two v6 sockets, but
only if the initiator supports IPv6 with v4-mapped addresses.

This change detects v4-mapped address on v6 sockets for the wildcard
case, and instead formats the TargetAddress response as an IPv4 address.

In order to not further complicate iscsit_build_sendtargets_response,
I've actually simplified it by moving the bracket wrapping of IPv6
address into iscsit_accept_np where local_ip and login_ip strings are
set.  That also simplifies iscsi_stat_tgt_attr_show_attr_fail_intr_addr.

Side effect of the string format change is that
lio_target_nacl_show_info will now print login_ip bracket wrapped for
IPv6 connections, as will a few debug prints.
Signed-off-by: NChris Leech <cleech@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The usage of strict_strtoul() and strict_strtoull() is not preferred,
because strict_strtoul() and strict_strtoull() are obsolete. Thus,
kstrtoul() and kstrtoull() should be used.

v2: Fix incorrect return in ft_add_tpg (Fengguang)
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
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>

Three have been checked for but were never set.  Remove the dead code.
Also renumbers the remaining ones to a) get rid of the holes after the
removal and b) avoid a collision between TMR_FUNCTION_COMPLETE==0 and
the uninitialized case.  If we failed to set a code, we should rather
fall into the default case then return success.
Signed-off-by: NJoern Engel <joern@logfs.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch includes the conversion of iscsi-target configfs
attributes for NetworkPortal, NodeACL, TPG, IQN and Discovery
groups to use kstrtou*() instead of simple_strtou*().

It also cleans up new-line usage during iscsi_tpg_param_store_##name
to use isspace().
Signed-off-by: NJoern Engel <joern@logfs.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes another potential buffer overflow while processing
iscsi_node_auth input for configfs attributes in v3.11 for-next
TPG tfc_tpg_auth_cit context.
Reported-by: NJoern Engel <joern@logfs.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a potential buffer overflow while processing
iscsi_node_auth input for configfs attributes within NodeACL
tfc_tpg_nacl_auth_cit context.
Signed-off-by: NJoern Engel <joern@logfs.org>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch addresses a bug where RDMA_CM_EVENT_DISCONNECTED may occur
before the connection shutdown has been completed by rx/tx threads,
that causes isert_free_conn() to wait indefinately on ->conn_wait.

This patch allows isert_disconnect_work code to invoke rdma_disconnect
when isert_disconnect_work() process context is started by client
session reset before isert_free_conn() code has been reached.

It also adds isert_conn->conn_mutex protection for ->state within
isert_disconnect_work(), isert_cq_comp_err() and isert_free_conn()
code, along with isert_check_state() for wait_event usage.

(v2: Add explicit iscsit_cause_connection_reinstatement call
     during isert_disconnect_work() to force conn reset)

Cc: stable@vger.kernel.org  # 3.10+
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds target_get_sess_cmd reference counting for
iscsit_handle_task_mgt_cmd(), and adds a target_put_sess_cmd()
for the failure case.

It also fixes a bug where ISCSI_OP_SCSI_TMFUNC type commands
where leaking iscsi_cmd->i_conn_node and eventually triggering
an OOPs during struct isert_conn shutdown.

Cc: stable@vger.kernel.org  # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch moves ISCSI_OP_REJECT failures into iscsit_sequence_cmd()
in order to avoid external iscsit_reject_cmd() reject usage for all
PDU types.

It also updates PDU specific handlers for traditional iscsi-target
code to not reset the session after posting a ISCSI_OP_REJECT during
setup.

(v2: Fix CMDSN_LOWER_THAN_EXP for ISCSI_OP_SCSI to call
     target_put_sess_cmd() after iscsit_sequence_cmd() failure)

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: stable@vger.kernel.org  # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch changes iscsit_add_reject() + iscsit_add_reject_from_cmd()
usage to not sleep on iscsi_cmd->reject_comp to address a free-after-use
usage bug in v3.10 with iser-target code.

It saves ->reject_reason for use within iscsit_build_reject() so the
correct value for both transport cases.  It also drops the legacy
fail_conn parameter usage throughput iscsi-target code and adds
two iscsit_add_reject_cmd() and iscsit_reject_cmd helper functions,
along with various small cleanups.

(v2: Re-enable target_put_sess_cmd() to be called from
     iscsit_add_reject_from_cmd() for rejects invoked after
     target_get_sess_cmd() has been called)

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: stable@vger.kernel.org  # 3.10+
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Fix-up breakage in iscsit_build_sendtargets_response() from v3.11
changes, and free "payload" before returning.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

All REJECT response setup of the rejected payload is now done using
on-demand cmd->buf_ptr allocations.

Go ahead and remove dead iscsi_conn->bad_hdr usage rx_opcode path
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds a auth configfs group context following existing
explict NodeACL and discovery auth within:

  /sys/kernel/config/target/iscsi/$TARGETNAME/$TPGT/auth/

This patch allows these attributes to be used for CHAP authentication
an TPG is configured in demo-mode (generate_node_acl=1).

Note this authentication information takes precedence over NodeACL
authentication when struct se_node_acl->dynamic_node_acl is present.

Cc: Dax Kelson <dkelson@gurulabs.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>