scsi: target: iscsi: Rename iscsi_session to iscsit_session

The structure iscsi_session naming is used by the iSCSI initiator
driver. Rename the target session to iscsit_session to have more readable
code.

Link: https://lore.kernel.org/r/20220428092939.36768-3-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Rename iscsi_conn to iscsit_conn

The structure iscsi_conn naming is used by the iSCSI initiator
driver. Rename the target conn to iscsit_conn to have more readable code.

Link: https://lore.kernel.org/r/20220428092939.36768-2-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Rename iscsi_cmd to iscsit_cmd

The structure iscsi_cmd naming is used by the iSCSI initiator driver.
Rename the target cmd to iscsit_cmd to have more readable code.

Link: https://lore.kernel.org/r/20220428092939.36768-1-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Avoid in_interrupt() usage in iscsit_close_session()

iscsit_close_session() uses in_interrupt() to decide if it needs to check
the return value of iscsit_check_session_usage_count() if it was not able
to sleep.

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

iscsit_close_session() has two callers:

- iscsit_handle_time2retain_timeout()
A timer_list callback.

- iscsit_close_connection()
Runs in preemptible context, acquires a mutex.

Add an argument to iscsit_close_session() indicating if sleeping is
possible.

Link: https://lore.kernel.org/r/20201220203638.43615-2-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157

Based on 3 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: target/iscsi: Convert comments about locking into runtime checks

Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: split out helper for cxn timeout error stashing

Replace existing nested code blocks with helper function calls.

Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

target/iscsi: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Includes a fix for correcting an
on-stack timer usage.

Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Jiang Yi <jiangyilism@gmail.com>
Cc: Varun Prakash <varun@chelsio.com>
Cc: linux-scsi@vger.kernel.org
Cc: target-devel@vger.kernel.org
Reviewed-and-Tested-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

target/iscsi: Simplify timer manipulation code

Move timer initialization from before add_timer() to the context
where the containing object is initialized. Use setup_timer() and
mod_timer() instead of open coding these. Use 'jiffies' instead
of get_jiffies_64() when calculating expiry times because expiry
times have type unsigned long, just like 'jiffies'.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: David Disseldorp <ddiss@suse.de>
Signed-off-by: Kees Cook <keescook@chromium.org>

iscsi-target: Always wait for kthread_should_stop() before kthread exit

There are three timing problems in the kthread usages of iscsi_target_mod:

- np_thread of struct iscsi_np
- rx_thread and tx_thread of struct iscsi_conn

In iscsit_close_connection(), it calls

send_sig(SIGINT, conn->tx_thread, 1);
kthread_stop(conn->tx_thread);

In conn->tx_thread, which is iscsi_target_tx_thread(), when it receive
SIGINT the kthread will exit without checking the return value of
kthread_should_stop().

So if iscsi_target_tx_thread() exit right between send_sig(SIGINT...)
and kthread_stop(...), the kthread_stop() will try to stop an already
stopped kthread.

This is invalid according to the documentation of kthread_stop().

(Fix -ECONNRESET logout handling in iscsi_target_tx_thread and
early iscsi_target_rx_thread failure case - nab)

Signed-off-by: Jiang Yi <jiangyilism@gmail.com>
Cc: <stable@vger.kernel.org> # v3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>

We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

target/iscsi: Fix unsolicited data seq_end_offset calculation

In case of unsolicited data for the first sequence
seq_end_offset must be set to minimum of total data length
and FirstBurstLength, so do not add cmd->write_data_done
to the min of total data length and FirstBurstLength.

This patch avoids that with ImmediateData=Yes, InitialR2T=No,
MaxXmitDataSegmentLength < FirstBurstLength that a WRITE command
with IO size above FirstBurstLength triggers sequence error
messages, for example

Set following parameters on target (linux-4.8.12)
ImmediateData = Yes
InitialR2T = No
MaxXmitDataSegmentLength = 8k
FirstBurstLength = 64k

Log in from Open iSCSI initiator and execute
dd if=/dev/zero of=/dev/sdb bs=128k count=1 oflag=direct

Error messages on target
Command ITT: 0x00000035 with Offset: 65536, Length: 8192 outside
of Sequence 73728:131072 while DataSequenceInOrder=Yes.
Command ITT: 0x00000035, received DataSN: 0x00000001 higher than
expected 0x00000000.
Unable to perform within-command recovery while ERL=0.

Signed-off-by: Varun Prakash <varun@chelsio.com>
[ bvanassche: Use min() instead of open-coding it / edited patch description ]
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: remove usage of ->shutdown_session

->shutdown session only decideѕ if the target core calls ->close_session
directly, or if the fabrics drivers calls it manually later through
target_put_session, which at this point will always close the session as
it has been removed from the lookup list and thus no new references will
be acquired from the core.

So instead remove ->shutdown and have the core call ->close_session
directly, and replace all calls to target_put_session in the iSCSI target
with direct calls to iscsit_close_session.

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

iscsi-target: remove support for obsolete markers

Support for markers is currently broken because of a bug in
iscsi_enforce_integrity_rules(): the "IFMarkInt_Reject" and
"OFMarkInt_Reject" variables are always equal to 1 in
iscsi_enforce_integrity_rules().

Moreover, fixed interval markers keys (IFMarker, OFMarker, IFMarkInt
and OFMarkInt) are obsolete according to iSCSI RFC 7143:

>From http://tools.ietf.org/html/rfc7143#section-13.25:

13.25. Obsoleted Keys

This document obsoletes the following keys defined in [RFC3720]:
IFMarker, OFMarker, OFMarkInt, and IFMarkInt. However, iSCSI
implementations compliant to this document may still receive these
obsoleted keys -- i.e., in a responder role -- in a text negotiation.

When an IFMarker or OFMarker key is received, a compliant iSCSI
implementation SHOULD respond with the constant "Reject" value. The
implementation MAY alternatively respond with a "No" value.

However, the implementation MUST NOT respond with a "NotUnderstood"
value for either of these keys.

When an IFMarkInt or OFMarkInt key is received, a compliant iSCSI
implementation MUST respond with the constant "Reject" value. The
implementation MUST NOT respond with a "NotUnderstood" value for
either of these keys.

This patch disables markers by turning the corresponding parameters to
read-only. The default value of IFMarker and OFMarker remains "No" but
the user cannot change it to "Yes" anymore. The new value of IFMarkInt
and OFMarkInt is "Reject".

(Drop left-over iscsi_get_value_from_number_range + make configfs
parameters attrs R/W nops - nab)

Signed-off-by: Christophe Vu-Brugier <cvubrugier@fastmail.fm>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Drop legacy iscsi_target_tq.c logic

Now that iscsi_conn allocates new [rx,tx] threads using kthread.h
primitives on the fly, and kthread_stop() is called directly during
connection shutdown, it's time to go ahead and drop iscsi_target_tq.c
legacy code.

The use of multiple struct completion in iscsi_activate_thread_set()
has been proven to cause issues during repeated iser login/logout.

Tested-by: Sagi Grimberg <sagig@mellanox.com>
Cc: Slava Shwartsman <valyushash@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Convert iscsi_thread_set usage to kthread.h

This patch converts iscsi-target code to use modern kthread.h API
callers for creating RX/TX threads for each new iscsi_conn descriptor,
and releasing associated RX/TX threads during connection shutdown.

This is done using iscsit_start_kthreads() -> kthread_run() to start
new kthreads from within iscsi_post_login_handler(), and invoking
kthread_stop() from existing iscsit_close_connection() code.

Also, convert iscsit_logout_post_handler_closesession() code to use
cmpxchg when determing when iscsit_cause_connection_reinstatement()
needs to sleep waiting for completion.

Reported-by: Sagi Grimberg <sagig@mellanox.com>
Tested-by: Sagi Grimberg <sagig@mellanox.com>
Cc: Slava Shwartsman <valyushash@gmail.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Revert "iscsi-target: Avoid IN_LOGOUT failure case for iser-target"

This reverts commit 72859d91d93319c00a18c29f577e56bf73a8654a.

The original patch was wrong, iscsit_close_connection() still needs
to release iscsi_conn during both normal + exception IN_LOGOUT status
with ib_isert enabled.

The original OOPs is due to completing conn_logout_comp early within
iscsit_close_connection(), causing isert_wait4logout() to complete
instead of waiting for iscsit_logout_post_handler_*() to be called.

Reported-by: Sagi Grimberg <sagig@mellanox.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Slava Shwartsman <valyushash@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Avoid IN_LOGOUT failure case for iser-target

This patch addresses a bug reported during iser-target login/logout
stress testing, where iscsit_take_action_for_connection_exit() is
incorrectly invoking iscsit_close_connection() twice during IN_LOGOUT
state, after connection shutdown has already been initiated by
iser-target code.

Here is the backtrace:

BUG: unable to handle kernel NULL pointer dereference at 00000000000001f0
IP: [<ffffffffa033d992>] iscsit_take_action_for_connection_exit+0x62/0x110 [iscsi_target_mod]
PGD 0
Oops: 0000 [#1] SMP
Modules linked in: target_core_pscsi(O) target_core_file(O) target_core_iblock(O) ib_isert(O) iscsi_target_mod(O) ib_srpt(O) tcm_loop(O) tcm_fc(O) target_core_mod(O) mst_pciconf(OE) bonding mlx5_ib(O) mlx5_core libfc scsi_transport_fc netconsole configfs nfsv3 nfs_acl mlx4_ib(O) rdma_ucm(O) ib_ucm(O) rdma_cm(O) iw_cm(O) ib_uverbs(O) libiscsi_tcp libiscsi scsi_transport_iscsi mlx4_en mlx4_core ib_ipoib(O) ib_cm(O) ib_sa(O) ib_umad(O) ib_mad(O) ib_core(O) ib_addr(O) rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs fscache lockd grace autofs4 sunrpc 8021q garp stp llc ipv6 dm_mirror dm_region_hash dm_log dm_multipath uinput ipmi_si ipmi_msghandler acpi_pad iTCO_wdt iTCO_vendor_support dcdbas microcode pcspkr wmi sb_edac edac_core sg lpc_ich mfd_core shpchp tg3 ptp pps_core dm_mod ext3(E) jbd(E) mbcache(E) sr_mod(E) cdrom(E) sd_mod(E) ahci(E) libahci(E) megaraid_sas(E) [last unloaded: target_core_mod]
CPU: 2 PID: 5280 Comm: iscsi_ttx Tainted: G W OE 3.18.0-rc2+ #22
Hardware name: Dell Inc. PowerEdge R720/0VWT90, BIOS 2.0.9 03/08/2013
task: ffff8806132f9010 ti: ffff880601d6c000 task.ti: ffff880601d6c000
RIP: 0010:[<ffffffffa033d992>] [<ffffffffa033d992>] iscsit_take_action_for_connection_exit+0x62/0x110 [iscsi_target_mod]
RSP: 0018:ffff880601d6fe18 EFLAGS: 00010296
RAX: 0000000000000000 RBX: ffff8805dc437800 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000200 RDI: ffffffffa033d98b
RBP: ffff880601d6fe28 R08: 0000000000000000 R09: 000000000000dd37
R10: 00000000ec5d4202 R11: 0000000000000001 R12: ffff8805dc437bf4
R13: ffff88061b831600 R14: ffff880601d6fe58 R15: ffff8806132f9010
FS: 0000000000000000(0000) GS:ffff88032fa20000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000001f0 CR3: 0000000001a14000 CR4: 00000000000407e0
Stack:
ffff8805dc437800 fffffffffffffe00 ffff880601d6feb8 ffffffffa034ed40
ffff8806132f9010 ffff880601d6fe70 0f00000000000000 ffff8805d51fbef0
0000000000000000 ffff8806132f9010 ffffffff8108e7f0 ffff880601d6fe70
Call Trace:
[<ffffffffa034ed40>] iscsi_target_tx_thread+0x160/0x220 [iscsi_target_mod]
[<ffffffff8108e7f0>] ? bit_waitqueue+0xb0/0xb0
[<ffffffffa034ebe0>] ? iscsit_handle_snack+0x190/0x190 [iscsi_target_mod]
[<ffffffff8107017e>] kthread+0xce/0xf0
[<ffffffff810700b0>] ? kthread_freezable_should_stop+0x70/0x70
[<ffffffff815a0b6c>] ret_from_fork+0x7c/0xb0
[<ffffffff810700b0>] ? kthread_freezable_should_stop+0x70/0x70
Code: 06 0f 84 82 00 00 00 3c 08 74 4e f6 05 39 e6 02 00 04 0f 85 9e 00 00 00 c6 43 19 08 4c 89 e7 e8 65 2a 26 e1 48 8b 83 a0 04 00 00 <48> 8b 88 f0 01 00 00 80 b9 d8 04 00 00 02 74 2e f6 05 31 e6 02
RIP [<ffffffffa033d992>] iscsit_take_action_for_connection_exit+0x62/0x110 [iscsi_target_mod]
RSP <ffff880601d6fe18>
CR2: 00000000000001f0
---[ end trace a0c33436cd0836b4 ]---

This special case is still required by ISCSI_TCP transport during a
iscsit_handle_logout_cmd() failure case in iscsi_target_rx_opcode(),
but must be avoided for iser-target.

Reported-by: Sagi Grimberg <sagig@mellanox.com>
Reported-by: Slava Shwartsman <valyushash@gmail.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Slava Shwartsman <valyushash@gmail.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Move iscsi_target_[core,stat].h under linux include

Seems strange to see in include/target/iscsi/iscsi_transport.h:
include "../../../drivers/target/iscsi/iscsi_target_core.h"

Move it to it's natural location.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: simplify return statement

The return statement cannot be reached without either recovery or dump
being set to 1. Therefore the condition always evaluates to true and
recovery and dump are useless variables.

Found by Coverity.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Convert iscsi_session statistics to atomic_long_t

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: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: Remove macros that contain typecasts

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

ISCSI_TPG_LUN macro was unused.

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

target: Update copyright ownership/year information to 2013

Update copyright ownership/year information for target-core,
loopback, iscsi-target, tcm_qla2xx, vhost and iser-target.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iser-target: Fix session reset bug with RDMA_CM_EVENT_DISCONNECTED

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: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Fix iscsit_add_reject* usage for iser

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: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: don't corrupt bh_count in iscsit_stop_time2retain_timer()

Here is a fun one. Bug seems to have been introduced by commit 140854cb,
almost two years ago. I have no idea why we only started seeing it now,
but we did.

Rough callgraph:
core_tpg_set_initiator_node_queue_depth()
`-> spin_lock_irqsave(&tpg->session_lock, flags);
`-> lio_tpg_shutdown_session()
`-> iscsit_stop_time2retain_timer()
`-> spin_unlock_bh(&se_tpg->session_lock);
`-> spin_lock_bh(&se_tpg->session_lock);
`-> spin_unlock_irqrestore(&tpg->session_lock, flags);

core_tpg_set_initiator_node_queue_depth() used to call spin_lock_bh(),
but 140854cb changed that to spin_lock_irqsave(). However,
lio_tpg_shutdown_session() still claims to be called with spin_lock_bh()
held, as does iscsit_stop_time2retain_timer():
* Called with spin_lock_bh(&struct se_portal_group->session_lock) held

Stale documentation is mostly annoying, but in this case the dropping
the lock with the _bh variant is plain wrong. It is also wrong to drop
locks two functions below the lock-holder, but I will ignore that bit
for now.

After some more locking and unlocking we eventually hit this backtrace:
------------[ cut here ]------------
WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0xe8/0x100()
Pid: 24645, comm: lio_helper.py Tainted: G O 3.6.11+
Call Trace:
[<ffffffff8103e5ff>] warn_slowpath_common+0x7f/0xc0
[<ffffffffa040ae37>] ? iscsit_inc_conn_usage_count+0x37/0x50 [iscsi_target_mod]
[<ffffffff8103e65a>] warn_slowpath_null+0x1a/0x20
[<ffffffff810472f8>] local_bh_enable_ip+0xe8/0x100
[<ffffffff815b8365>] _raw_spin_unlock_bh+0x15/0x20
[<ffffffffa040ae37>] iscsit_inc_conn_usage_count+0x37/0x50 [iscsi_target_mod]
[<ffffffffa041149a>] iscsit_stop_session+0xfa/0x1c0 [iscsi_target_mod]
[<ffffffffa0417fab>] lio_tpg_shutdown_session+0x7b/0x90 [iscsi_target_mod]
[<ffffffffa033ede4>] core_tpg_set_initiator_node_queue_depth+0xe4/0x290 [target_core_mod]
[<ffffffffa0409032>] iscsit_tpg_set_initiator_node_queue_depth+0x12/0x20 [iscsi_target_mod]
[<ffffffffa0415c29>] lio_target_nacl_store_cmdsn_depth+0xa9/0x180 [iscsi_target_mod]
[<ffffffffa0331b49>] target_fabric_nacl_base_attr_store+0x39/0x40 [target_core_mod]
[<ffffffff811b857d>] configfs_write_file+0xbd/0x120
[<ffffffff81148f36>] vfs_write+0xc6/0x180
[<ffffffff81149251>] sys_write+0x51/0x90
[<ffffffff815c0969>] system_call_fastpath+0x16/0x1b
---[ end trace 3747632b9b164652 ]---

As a pure band-aid, this patch drops the _bh.

Signed-off-by: Joern Engel <joern@logfs.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target: iscsi: fix comment typos in target/iscsi drivers

Correct spelling typo in printk and comment within target/iscsi drivers

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

iscsit: proper endianess conversions

Make sure all on the wire types are use as big endian and big endian only so
that sparse can verify all the conversions are done right.

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

iscsit: mark various functions static

This patch marks a number of functions static to appease sparse static
checking.

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

target/iscsi: precedence bug in iscsit_set_dataout_sequence_values()

Clang warns about this bug:
drivers/target/iscsi/iscsi_target_erl0.c:52:45: warning: operator '?:'
has lower precedence than '+'; '+' will be evaluated first
[-Wparentheses]

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: Eliminate iscsi_cmd.data_length

Redundant, just use iscsi_cmd->se_cmd.data_length once se_cmd is
initialized, or hdr->data_length before then.

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

target/iscsi: Misc cleanups from Agrover (round 1)

*) Use decoded cmd->immediate_cmd for conditional instead of
re-examining hdr->opcode
*) Make iscist_dataout_post_crc_passed more legible
*) use max() to reduce code in build_r2ts_for_cmd()
*) Remove CONFIG_SMP and if 0 ifdefs
*) Replace if/goto with a while loop
*) Remove unused conn->tx_immediate_queue and tx_response_queue

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

iscsi-target: Convert to use target_put_session + sess_kref

This patch converts iscsi-target session code to use se_sess->sess_kref
counting for iscsi session shutdown. The following cases include:

*) last iscsit_close_connection() shutdown path to invoke close session
*) iscsit_logout_post_handler_closesession() for explict logout
*) iscsit_free_session() caller for explict shutdown

It also moves iscsit_stop_session() call from lio_tpg_close_session()
into lio_tpg_shutdown_session() TFO callbacks to invoke an explict
shutdown, and also changes iscsi_check_for_session_reinstatement()
login code to use se_sess->sess_kref.

(v2: Make iscsit_handle_time2retain_timeout() use target_put_session)

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

target: header reshuffle, part2

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

iscsi-target: Add iSCSI fabric support for target v4.1

The Linux-iSCSI.org target module is a full featured in-kernel
software implementation of iSCSI target mode (RFC-3720) for the
current WIP mainline target v4.1 infrastructure code for the v3.1
kernel. More information can be found here:

http://linux-iscsi.org/wiki/ISCSI

This includes support for:

* RFC-3720 defined request / response state machines and support for
all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi
include/scsi/iscsi_proto.h PDU definitions
* Target v4.1 compatible control plane using the generic layout in
target_core_fabric_configfs.c and fabric dependent attributes
within /sys/kernel/config/target/iscsi/ subdirectories.
* Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS)
* Support for IPv6 and IPv4 network portals in M:N mapping to TPGs
* iSCSI Error Recovery Hierarchy support
* Per iSCSI connection RX/TX thread pair scheduling affinity
* crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto
* CHAP Authentication support using libcrypto
* Conversion to use internal SGl allocation with iscsit_alloc_buffs() ->
transport_generic_map_mem_to_cmd()

(nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit:
iscsi: Use struct scsi_lun in iscsi structs instead of u8[8])
(nab: Fix 32-bit compile warnings)

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Grover <agrover@redhat.com>
Acked-by: Roland Dreier <roland@kernel.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>