linux-stable.git/drivers/target/tcm_fc, branch linux-3.7.y

tcm_fc: Do not report target role when target is not defined

2013-01-21T19:44:33+00:00

commit edec8dfefa1f372b2dd8197da555352e76a10c03 upstream.

Clear the target role when no target is provided for
the node performing a PRLI.

Signed-off-by: Mark Rustad 
Reviewed-by: Bhanu Prakash Gollapudi 
Acked by Robert Love 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

tcm_fc: Do not indicate retry capability to initiators

2013-01-21T19:44:33+00:00

commit f2eeba214bcd0215b7f558cab6420e5fd153042b upstream.

When generating a PRLI response to an initiator, clear the
FCP_SPPF_RETRY bit in the response.

Signed-off-by: Mark Rustad 
Reviewed-by: Bhanu Prakash Gollapudi 
Acked by Robert Love 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target/tcm_fc: fix the lockdep warning due to inconsistent lock state

2013-01-17T16:45:58+00:00

commit 9f4ad44b264f8bb61ffdd607148215566568430d upstream.

The lockdep warning below is in theory correct but it will be in really weird
rare situation that ends up that deadlock since the tcm fc session is hashed
based the rport id. Nonetheless, the complaining below is about rcu callback
that does the transport_deregister_session() is happening in softirq, where
transport_register_session() that happens earlier is not. This triggers the
lockdep warning below. So, just fix this to make lockdep happy by disabling
the soft irq before calling transport_register_session() in ft_prli.

BTW, this was found in FCoE VN2VN over two VMs, couple of create and destroy
would get this triggered.

v1: was enforcing register to be in softirq context which was not righ. See,
http://www.spinics.net/lists/target-devel/msg03614.html

v2: following comments from Roland&Nick (thanks), it seems we don't have to
do transport_deregister_session() in rcu callback, so move it into ft_sess_free()
but still do kfree() of the corresponding ft_sess struct in rcu callback to
make sure the ft_sess is not freed till the rcu callback.

...
[ 1328.370592] scsi2 : FCoE Driver
[ 1328.383429] fcoe: No FDMI support.
[ 1328.384509] host2: libfc: Link up on port (000000)
[ 1328.934229] host2: Assigned Port ID 00a292
[ 1357.232132] host2: rport 00a393: Remove port
[ 1357.232568] host2: rport 00a393: Port sending LOGO from Ready state
[ 1357.233692] host2: rport 00a393: Delete port
[ 1357.234472] host2: rport 00a393: work event 3
[ 1357.234969] host2: rport 00a393: callback ev 3
[ 1357.235979] host2: rport 00a393: Received a LOGO response closed
[ 1357.236706] host2: rport 00a393: work delete
[ 1357.237481]
[ 1357.237631] =================================
[ 1357.238064] [ INFO: inconsistent lock state ]
[ 1357.238450] 3.7.0-rc7-yikvm+ #3 Tainted: G           O
[ 1357.238450] ---------------------------------
[ 1357.238450] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[ 1357.238450] ksoftirqd/0/3 [HC0[0]:SC1[1]:HE0:SE0] takes:
[ 1357.238450]  (&(&se_tpg->session_lock)->rlock){+.?...}, at: [] transport_deregister_session+0x41/0x148 [target_core_mod]
[ 1357.238450] {SOFTIRQ-ON-W} state was registered at:
[ 1357.238450]   [] mark_held_locks+0x6d/0x95
[ 1357.238450]   [] trace_hardirqs_on_caller+0x12d/0x197
[ 1357.238450]   [] trace_hardirqs_on+0xd/0xf
[ 1357.238450]   [] _raw_spin_unlock_irq+0x2d/0x45
[ 1357.238450]   [] __transport_register_session+0xb8/0x122 [target_core_mod]
[ 1357.238450]   [] transport_register_session+0x44/0x5a [target_core_mod]
[ 1357.238450]   [] ft_prli+0x1e3/0x275 [tcm_fc]
[ 1357.238450]   [] fc_rport_recv_req+0x95e/0xdc5 [libfc]
[ 1357.238450]   [] fc_lport_recv_els_req+0xc4/0xd5 [libfc]
[ 1357.238450]   [] fc_lport_recv_req+0x12f/0x18f [libfc]
[ 1357.238450]   [] fc_exch_recv+0x8ba/0x981 [libfc]
[ 1357.238450]   [] fcoe_percpu_receive_thread+0x47a/0x4e2 [fcoe]
[ 1357.238450]   [] kthread+0xb1/0xb9
[ 1357.238450]   [] ret_from_fork+0x7c/0xb0
[ 1357.238450] irq event stamp: 275411
[ 1357.238450] hardirqs last  enabled at (275410): [] rcu_process_callbacks+0x229/0x42a
[ 1357.238450] hardirqs last disabled at (275411): [] _raw_spin_lock_irqsave+0x22/0x8e
[ 1357.238450] softirqs last  enabled at (275394): [] __do_softirq+0x246/0x26f
[ 1357.238450] softirqs last disabled at (275399): [] run_ksoftirqd+0x29/0x62
[ 1357.238450]
[ 1357.238450] other info that might help us debug this:
[ 1357.238450]  Possible unsafe locking scenario:
[ 1357.238450]
[ 1357.238450]        CPU0
[ 1357.238450]        ----
[ 1357.238450]   lock(&(&se_tpg->session_lock)->rlock);
[ 1357.238450]   
[ 1357.238450]     lock(&(&se_tpg->session_lock)->rlock);
[ 1357.238450]
[ 1357.238450]  *** DEADLOCK ***
[ 1357.238450]
[ 1357.238450] no locks held by ksoftirqd/0/3.
[ 1357.238450]
[ 1357.238450] stack backtrace:
[ 1357.238450] Pid: 3, comm: ksoftirqd/0 Tainted: G           O 3.7.0-rc7-yikvm+ #3
[ 1357.238450] Call Trace:
[ 1357.238450]  [] print_usage_bug+0x1f5/0x206
[ 1357.238450]  [] ? save_stack_trace+0x2c/0x49
[ 1357.238450]  [] ? print_irq_inversion_bug.part.14+0x1ae/0x1ae
[ 1357.238450]  [] mark_lock+0x106/0x258
[ 1357.238450]  [] __lock_acquire+0x2e7/0xe53
[ 1357.238450]  [] ? pvclock_clocksource_read+0x48/0xb4
[ 1357.238450]  [] ? rcu_process_gp_end+0xc0/0xc9
[ 1357.238450]  [] ? transport_deregister_session+0x41/0x148 [target_core_mod]
[ 1357.238450]  [] lock_acquire+0x119/0x143
[ 1357.238450]  [] ? transport_deregister_session+0x41/0x148 [target_core_mod]
[ 1357.238450]  [] _raw_spin_lock_irqsave+0x54/0x8e
[ 1357.238450]  [] ? transport_deregister_session+0x41/0x148 [target_core_mod]
[ 1357.238450]  [] transport_deregister_session+0x41/0x148 [target_core_mod]
[ 1357.238450]  [] ? rcu_process_callbacks+0x229/0x42a
[ 1357.238450]  [] ft_sess_rcu_free+0x17/0x24 [tcm_fc]
[ 1357.238450]  [] ? ft_sess_free+0x1b/0x1b [tcm_fc]
[ 1357.238450]  [] rcu_process_callbacks+0x260/0x42a
[ 1357.238450]  [] __do_softirq+0x13a/0x26f
[ 1357.238450]  [] ? __schedule+0x65f/0x68e
[ 1357.238450]  [] run_ksoftirqd+0x29/0x62
[ 1357.238450]  [] smpboot_thread_fn+0x1a5/0x1aa
[ 1357.238450]  [] ? smpboot_unregister_percpu_thread+0x47/0x47
[ 1357.238450]  [] kthread+0xb1/0xb9
[ 1357.238450]  [] ? wait_for_common+0xbb/0x10a
[ 1357.238450]  [] ? __init_kthread_worker+0x59/0x59
[ 1357.238450]  [] ret_from_fork+0x7c/0xb0
[ 1357.238450]  [] ? __init_kthread_worker+0x59/0x59
[ 1417.440099]  rport-2:0-0: blocked FC remote port time out: removing rport

Signed-off-by: Yi Zou 
Cc: Open-FCoE 
Cc: Nicholas A. Bellinger 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

tcm_fc: move the dereference below the NULL test

2012-09-18T01:04:09+00:00

The dereference should be moved below the NULL test.

spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)

Signed-off-by: Wei Yongjun 
Signed-off-by: Nicholas Bellinger

tcm_fc: remove unused including

2012-09-18T00:13:33+00:00

Remove including  that don't need it.

Signed-off-by: Wei Yongjun 
Signed-off-by: Nicholas Bellinger

target: Simplify fabric sense data length handling

2012-09-18T00:12:58+00:00

Every fabric driver has to supply a se_tfo->set_fabric_sense_len()
method, just so iSCSI can return an offset of 2.  However, every fabric
driver is already allocating a sense buffer and passing it into the
target core, either via transport_init_se_cmd() or target_submit_cmd().

So instead of having iSCSI pass the start of its sense buffer into the
core and then later tell the core to skip the first 2 bytes, it seems
easier for iSCSI just to do the offset of 2 when it passes the sense
buffer into the core.  Then we can drop the se_tfo->set_fabric_sense_len()
everywhere, and just add a couple of lines of code to iSCSI to set the
sense data length to the beginning of the buffer right before it sends
it over the network.

(nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops +
      change transport_get_sense_buffer to follow v3.6-rc6 code w/o
      ->set_fabric_sense_len usage)

Signed-off-by: Roland Dreier 
Signed-off-by: Nicholas Bellinger

target: Remove unused target_core_fabric_ops.get_fabric_sense_len method

2012-09-17T23:15:47+00:00

There are no callers of se_tfo->get_fabric_sense_len(), so we should
stop having every fabric driver implement it.

Signed-off-by: Roland Dreier 
Signed-off-by: Nicholas Bellinger

tcm_fc: rcu_deref outside rcu lock/unlock section

2012-08-20T21:52:15+00:00

Use rcu_dereference_protected in order to prevent lockdep
complaint. Sequel of the patch 863555be

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Denis Efremov 
Acked-by: Mark D. Rustad 
Signed-off-by: Nicholas Bellinger

tcm_fc: Avoid debug overhead when not debugging

2012-08-17T00:33:46+00:00

Stop doing a pile of work related to debugging messages when
the ft_debug_logging flag is not set. Use unlikely to add the
check in a way that the check can be inlined without inlining the
whole thing.

Signed-off-by: Mark Rustad 
Signed-off-by: Nicholas Bellinger

target: Allow for target_submit_cmd() returning errors

2012-07-18T00:05:05+00:00

We want it to be possible for target_submit_cmd() to return errors up
to its fabric module callers.  For now just update the prototype to
return an int, and update all callers to handle non-zero return values
as an error.

This is immediately useful for tcm_qla2xxx to fix a long-standing active
I/O session shutdown race, but tcm_fc, usb-gadget, and sbp-target the
fabric maintainers need to check + ACK that handling a target_submit_cmd()
failure due to session shutdown does not introduce regressions

(nab: Respin against for-next after initial NACK + update docbook comment +
      fix double se_cmd init in exception path for usb-gadget)

Cc: Chad Dupuis 
Cc: Arun Easi 
Cc: Chris Boot 
Cc: Stefan Richter 
Cc: Mark Rustad 
Cc: Sebastian Andrzej Siewior 
Cc: Felipe Balbi 
Cc: Andy Grover 
Signed-off-by: Roland Dreier 
Signed-off-by: Nicholas Bellinger