Improves commit 250a1352b9 ("[SCSI] zfcp: Redesign of the debug tracing
for SCSI records.")
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This eases crash dump analysis by automatically dissecting these
protocol headers at least somewhat rather than getting a string
interpretation of large unstructured character array buffer fields.
Also, we can get rid of some unnecessary and error-prone type casts.
This change is possible since v2.6.33 commit 4318e08c84
("[SCSI] zfcp: Update FCP protocol related code").
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Complements debugging aspects of the otherwise functionally complete
v3.17 commit 9cb78c16f5 ("scsi: use 64-bit LUNs").
While I don't have access to a target exporting 3 or 4 level LUNs,
I did test it by explicitly attaching a non-existent fake 4 level LUN
by means of zfcp sysfs attribute "unit_add".
In order to see corresponding trace records of otherwise successful
events, we had to increase the trace level of area SCSI and HBA to 6.
$ echo 6 > /sys/kernel/debug/s390dbf/zfcp_0.0.1880_scsi/level
$ echo 6 > /sys/kernel/debug/s390dbf/zfcp_0.0.1880_hba/level
$ echo 0x4011402240334044 > \
/sys/bus/ccw/drivers/zfcp/0.0.1880/0x50050763031bd327/unit_add
Example output formatted by an updated zfcpdbf from the s390-tools
package interspersed with kernel messages at scsi_logging_level=4605:
Timestamp : ...
Area : REC
Subarea : 00
Level : 1
Exception : -
CPU ID : ..
Caller : 0x...
Record ID : 1
Tag : scsla_1
LUN : 0x4011402240334044
WWPN : 0x50050763031bd327
D_ID : 0x00......
Adapter status : 0x5400050b
Port status : 0x54000001
LUN status : 0x41000000
Ready count : 0x00000001
Running count : 0x00000000
ERP want : 0x01
ERP need : 0x01
scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY pass 1 length 36
scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY successful with code 0x0
Timestamp : ...
Area : HBA
Subarea : 00
Level : 6
Exception : -
CPU ID : ..
Caller : 0x...
Record ID : 1
Tag : fs_norm
Request ID : 0x<inquiry2-req-id>
Request status : 0x00000010
FSF cmnd : 0x00000001
FSF sequence no: 0x...
FSF issued : ...
FSF stat : 0x00000000
FSF stat qual : 00000000 00000000 00000000 00000000
Prot stat : 0x00000001
Prot stat qual : ........ ........ 00000000 00000000
Port handle : 0x...
LUN handle : 0x...
|
Timestamp : ...
Area : SCSI
Subarea : 00
Level : 6
Exception : -
CPU ID : ..
Caller : 0x...
Record ID : 1
Tag : rsl_nor
Request ID : 0x<inquiry2-req-id>
SCSI ID : 0x00000000
SCSI LUN : 0x40224011
SCSI LUN high : 0x40444033 <=======================
SCSI result : 0x00000000
SCSI retries : 0x00
SCSI allowed : 0x03
SCSI scribble : 0x<inquiry2-req-id>
SCSI opcode : 12000000 a4000000 00000000 00000000
FCP rsp inf cod: 0x00
FCP rsp IU : 00000000 00000000 00000000 00000000
00000000 00000000
scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY pass 2 length 164
scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY successful with code 0x0
scsi 2:0:0:4630896905707208721: scsi scan: peripheral device type of 31, \
no device added
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 9cb78c16f5 ("scsi: use 64-bit LUNs")
Cc: <stable@vger.kernel.org> #3.17+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
At the default trace level, we only trace unsuccessful events including
FSF responses.
zfcp_dbf_hba_fsf_response() only used protocol status and FSF status to
decide on an unsuccessful response. However, this is only one of multiple
possible sources determining a failed struct zfcp_fsf_req.
An FSF request can also "fail" if its response runs into an ERP timeout
or if it gets dismissed because a higher level recovery was triggered
[trace tags "erscf_1" or "erscf_2" in zfcp_erp_strategy_check_fsfreq()].
FSF requests with ERP timeout are:
FSF_QTCB_EXCHANGE_CONFIG_DATA, FSF_QTCB_EXCHANGE_PORT_DATA,
FSF_QTCB_OPEN_PORT_WITH_DID or FSF_QTCB_CLOSE_PORT or
FSF_QTCB_CLOSE_PHYSICAL_PORT for target ports,
FSF_QTCB_OPEN_LUN, FSF_QTCB_CLOSE_LUN.
One example is slow queue processing which can cause follow-on errors,
e.g. FSF_PORT_ALREADY_OPEN after FSF_QTCB_OPEN_PORT_WITH_DID timed out.
In order to see the root cause, we need to see late responses even if the
channel presented them successfully with FSF_PROT_GOOD and FSF_GOOD.
Example trace records formatted with zfcpdbf from the s390-tools package:
Timestamp : ...
Area : REC
Subarea : 00
Level : 1
Exception : -
CPU ID : ..
Caller : ...
Record ID : 1
Tag : fcegpf1
LUN : 0xffffffffffffffff
WWPN : 0x<WWPN>
D_ID : 0x00<D_ID>
Adapter status : 0x5400050b
Port status : 0x41200000
LUN status : 0x00000000
Ready count : 0x00000001
Running count : 0x...
ERP want : 0x02 ZFCP_ERP_ACTION_REOPEN_PORT
ERP need : 0x02 ZFCP_ERP_ACTION_REOPEN_PORT
|
Timestamp : ... 30 seconds later
Area : REC
Subarea : 00
Level : 1
Exception : -
CPU ID : ..
Caller : ...
Record ID : 2
Tag : erscf_2
LUN : 0xffffffffffffffff
WWPN : 0x<WWPN>
D_ID : 0x00<D_ID>
Adapter status : 0x5400050b
Port status : 0x41200000
LUN status : 0x00000000
Request ID : 0x<request_ID>
ERP status : 0x10000000 ZFCP_STATUS_ERP_TIMEDOUT
ERP step : 0x0800 ZFCP_ERP_STEP_PORT_OPENING
ERP action : 0x02 ZFCP_ERP_ACTION_REOPEN_PORT
ERP count : 0x00
|
Timestamp : ... later than previous record
Area : HBA
Subarea : 00
Level : 5 > default level => 3 <= default level
Exception : -
CPU ID : 00
Caller : ...
Record ID : 1
Tag : fs_qtcb => fs_rerr
Request ID : 0x<request_ID>
Request status : 0x00001010 ZFCP_STATUS_FSFREQ_DISMISSED
| ZFCP_STATUS_FSFREQ_CLEANUP
FSF cmnd : 0x00000005
FSF sequence no: 0x...
FSF issued : ... > 30 seconds ago
FSF stat : 0x00000000 FSF_GOOD
FSF stat qual : 00000000 00000000 00000000 00000000
Prot stat : 0x00000001 FSF_PROT_GOOD
Prot stat qual : 00000000 00000000 00000000 00000000
Port handle : 0x...
LUN handle : 0x00000000
QTCB log length: ...
QTCB log info : ...
In case of problems detecting that new responses are waiting on the input
queue, we sooner or later trigger adapter recovery due to an FSF request
timeout (trace tag "fsrth_1").
FSF requests with FSF request timeout are:
typically FSF_QTCB_ABORT_FCP_CMND; but theoretically also
FSF_QTCB_EXCHANGE_CONFIG_DATA or FSF_QTCB_EXCHANGE_PORT_DATA via sysfs,
FSF_QTCB_OPEN_PORT_WITH_DID or FSF_QTCB_CLOSE_PORT for WKA ports,
FSF_QTCB_FCP_CMND for task management function (LUN / target reset).
One or more pending requests can meanwhile have FSF_PROT_GOOD and FSF_GOOD
because the channel filled in the response via DMA into the request's QTCB.
In a theroretical case, inject code can create an erroneous FSF request
on purpose. If data router is enabled, it uses deferred error reporting.
A READ SCSI command can succeed with FSF_PROT_GOOD, FSF_GOOD, and
SAM_STAT_GOOD. But on writing the read data to host memory via DMA,
it can still fail, e.g. if an intentionally wrong scatter list does not
provide enough space. Rather than getting an unsuccessful response,
we get a QDIO activate check which in turn triggers adapter recovery.
One or more pending requests can meanwhile have FSF_PROT_GOOD and FSF_GOOD
because the channel filled in the response via DMA into the request's QTCB.
Example trace records formatted with zfcpdbf from the s390-tools package:
Timestamp : ...
Area : HBA
Subarea : 00
Level : 6 > default level => 3 <= default level
Exception : -
CPU ID : ..
Caller : ...
Record ID : 1
Tag : fs_norm => fs_rerr
Request ID : 0x<request_ID2>
Request status : 0x00001010 ZFCP_STATUS_FSFREQ_DISMISSED
| ZFCP_STATUS_FSFREQ_CLEANUP
FSF cmnd : 0x00000001
FSF sequence no: 0x...
FSF issued : ...
FSF stat : 0x00000000 FSF_GOOD
FSF stat qual : 00000000 00000000 00000000 00000000
Prot stat : 0x00000001 FSF_PROT_GOOD
Prot stat qual : ........ ........ 00000000 00000000
Port handle : 0x...
LUN handle : 0x...
|
Timestamp : ...
Area : SCSI
Subarea : 00
Level : 3
Exception : -
CPU ID : ..
Caller : ...
Record ID : 1
Tag : rsl_err
Request ID : 0x<request_ID2>
SCSI ID : 0x...
SCSI LUN : 0x...
SCSI result : 0x000e0000 DID_TRANSPORT_DISRUPTED
SCSI retries : 0x00
SCSI allowed : 0x05
SCSI scribble : 0x<request_ID2>
SCSI opcode : 28... Read(10)
FCP rsp inf cod: 0x00
FCP rsp IU : 00000000 00000000 00000000 00000000
^^ SAM_STAT_GOOD
00000000 00000000
Only with luck in both above cases, we could see a follow-on trace record
of an unsuccesful event following a successful but late FSF response with
FSF_PROT_GOOD and FSF_GOOD. Typically this was the case for I/O requests
resulting in a SCSI trace record "rsl_err" with DID_TRANSPORT_DISRUPTED
[On ZFCP_STATUS_FSFREQ_DISMISSED, zfcp_fsf_protstatus_eval() sets
ZFCP_STATUS_FSFREQ_ERROR seen by the request handler functions as failure].
However, the reason for this follow-on trace was invisible because the
corresponding HBA trace record was missing at the default trace level
(by default hidden records with tags "fs_norm", "fs_qtcb", or "fs_open").
On adapter recovery, after we had shut down the QDIO queues, we perform
unsuccessful pseudo completions with flag ZFCP_STATUS_FSFREQ_DISMISSED
for each pending FSF request in zfcp_fsf_req_dismiss_all().
In order to find the root cause, we need to see all pseudo responses even
if the channel presented them successfully with FSF_PROT_GOOD and FSF_GOOD.
Therefore, check zfcp_fsf_req.status for ZFCP_STATUS_FSFREQ_DISMISSED
or ZFCP_STATUS_FSFREQ_ERROR and trace with a new tag "fs_rerr".
It does not matter that there are numerous places which set
ZFCP_STATUS_FSFREQ_ERROR after the location where we trace an FSF response
early. These cases are based on protocol status != FSF_PROT_GOOD or
== FSF_PROT_FSF_STATUS_PRESENTED and are thus already traced by default
as trace tag "fs_perr" or "fs_ferr" respectively.
NB: The trace record with tag "fssrh_1" for status read buffers on dismiss
all remains. zfcp_fsf_req_complete() handles this and returns early.
All other FSF request types are handled separately and as described above.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 8a36e4532e ("[SCSI] zfcp: enhancement of zfcp debug features")
Fixes: 2e261af84c ("[SCSI] zfcp: Only collect FSF/HBA debug data for matching trace levels")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Without this fix we get SCSI trace records on task management functions
which cannot be correlated to HBA trace records because all fields
related to the FSF request are empty (zero).
Also, the FCP_RSP_IU is missing as well as any sense data if available.
This was caused by v2.6.14 commit 8a36e4532e ("[SCSI] zfcp: enhancement
of zfcp debug features") introducing trace records for TMFs but
hard coding NULL for a possibly existing TMF FSF request.
The scsi_cmnd scribble is also zero or unrelated for the TMF request
so it also could not lookup a suitable FSF request from there.
A broken example trace record formatted with zfcpdbf from the s390-tools
package:
Timestamp : ...
Area : SCSI
Subarea : 00
Level : 1
Exception : -
CPU ID : ..
Caller : 0x...
Record ID : 1
Tag : lr_fail
Request ID : 0x0000000000000000
^^^^^^^^^^^^^^^^ no correlation to HBA record
SCSI ID : 0x<scsitarget>
SCSI LUN : 0x<scsilun>
SCSI result : 0x000e0000
SCSI retries : 0x00
SCSI allowed : 0x05
SCSI scribble : 0x0000000000000000
SCSI opcode : 2a000017 3bb80000 08000000 00000000
FCP rsp inf cod: 0x00
^^ no TMF response
FCP rsp IU : 00000000 00000000 00000000 00000000
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
00000000 00000000
^^^^^^^^^^^^^^^^^ no interesting FCP_RSP_IU
Sense len : ...
^^^^^^^^^^^^^^^^^^^^ no sense data length
Sense info : ...
^^^^^^^^^^^^^^^^^^^^ no sense data content, even if present
There are some true cases where we really do not have an FSF request:
"rsl_fai" from zfcp_dbf_scsi_fail_send() called for early
returns / completions in zfcp_scsi_queuecommand(),
"abrt_or", "abrt_bl", "abrt_ru", "abrt_ar" from
zfcp_scsi_eh_abort_handler() where we did not get as far,
"lr_nres", "tr_nres" from zfcp_task_mgmt_function() where we're
successful and do not need to do anything because adapter stopped.
For these cases it's correct to pass NULL for fsf_req to _zfcp_dbf_scsi().
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 8a36e4532e ("[SCSI] zfcp: enhancement of zfcp debug features")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Since quite a while, Linux issues enough SCSI commands per scsi_device
which successfully return with FCP_RESID_UNDER, FSF_FCP_RSP_AVAILABLE,
and SAM_STAT_GOOD. This floods the HBA trace area and we cannot see
other and important HBA trace records long enough.
Therefore, do not trace HBA response errors for pure benign residual
under counts at the default trace level.
This excludes benign residual under count combined with other validity
bits set in FCP_RSP_IU, such as FCP_SNS_LEN_VAL. For all those other
cases, we still do want to see both the HBA record and the corresponding
SCSI record by default.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Cc: <stable@vger.kernel.org> #2.6.37+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When SCSI EH invokes zFCP's callbacks for eh_device_reset_handler() and
eh_target_reset_handler(), it expects us to relent the ownership over
the given scsi_cmnd and all other scsi_cmnds within the same scope - LUN
or target - when returning with SUCCESS from the callback ('release'
them). SCSI EH can then reuse those commands.
We did not follow this rule to release commands upon SUCCESS; and if
later a reply arrived for one of those supposed to be released commands,
we would still make use of the scsi_cmnd in our ingress tasklet. This
will at least result in undefined behavior or a kernel panic because of
a wrong kernel pointer dereference.
To fix this, we NULLify all pointers to scsi_cmnds (struct zfcp_fsf_req
*)->data in the matching scope if a TMF was successful. This is done
under the locks (struct zfcp_adapter *)->abort_lock and (struct
zfcp_reqlist *)->lock to prevent the requests from being removed from
the request-hashtable, and the ingress tasklet from making use of the
scsi_cmnd-pointer in zfcp_fsf_fcp_cmnd_handler().
For cases where a reply arrives during SCSI EH, but before we get a
chance to NULLify the pointer - but before we return from the callback
-, we assume that the code is protected from races via the CAS operation
in blk_complete_request() that is called in scsi_done().
The following stacktrace shows an example for a crash resulting from the
previous behavior:
Unable to handle kernel pointer dereference at virtual kernel address fffffee17a672000
Oops: 0038 [#1] SMP
CPU: 2 PID: 0 Comm: swapper/2 Not tainted
task: 00000003f7ff5be0 ti: 00000003f3d38000 task.ti: 00000003f3d38000
Krnl PSW : 0404d00180000000 00000000001156b0 (smp_vcpu_scheduled+0x18/0x40)
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
Krnl GPRS: 000000200000007e 0000000000000000 fffffee17a671fd8 0000000300000015
ffffffff80000000 00000000005dfde8 07000003f7f80e00 000000004fa4e800
000000036ce8d8f8 000000036ce8d9c0 00000003ece8fe00 ffffffff969c9e93
00000003fffffffd 000000036ce8da10 00000000003bf134 00000003f3b07918
Krnl Code: 00000000001156a2: a7190000 lghi %r1,0
00000000001156a6: a7380015 lhi %r3,21
#00000000001156aa: e32050000008 ag %r2,0(%r5)
>00000000001156b0: 482022b0 lh %r2,688(%r2)
00000000001156b4: ae123000 sigp %r1,%r2,0(%r3)
00000000001156b8: b2220020 ipm %r2
00000000001156bc: 8820001c srl %r2,28
00000000001156c0: c02700000001 xilf %r2,1
Call Trace:
([<0000000000000000>] 0x0)
[<000003ff807bdb8e>] zfcp_fsf_fcp_cmnd_handler+0x3de/0x490 [zfcp]
[<000003ff807be30a>] zfcp_fsf_req_complete+0x252/0x800 [zfcp]
[<000003ff807c0a48>] zfcp_fsf_reqid_check+0xe8/0x190 [zfcp]
[<000003ff807c194e>] zfcp_qdio_int_resp+0x66/0x188 [zfcp]
[<000003ff80440c64>] qdio_kick_handler+0xdc/0x310 [qdio]
[<000003ff804463d0>] __tiqdio_inbound_processing+0xf8/0xcd8 [qdio]
[<0000000000141fd4>] tasklet_action+0x9c/0x170
[<0000000000141550>] __do_softirq+0xe8/0x258
[<000000000010ce0a>] do_softirq+0xba/0xc0
[<000000000014187c>] irq_exit+0xc4/0xe8
[<000000000046b526>] do_IRQ+0x146/0x1d8
[<00000000005d6a3c>] io_return+0x0/0x8
[<00000000005d6422>] vtime_stop_cpu+0x4a/0xa0
([<0000000000000000>] 0x0)
[<0000000000103d8a>] arch_cpu_idle+0xa2/0xb0
[<0000000000197f94>] cpu_startup_entry+0x13c/0x1f8
[<0000000000114782>] smp_start_secondary+0xda/0xe8
[<00000000005d6efe>] restart_int_handler+0x56/0x6c
[<0000000000000000>] 0x0
Last Breaking-Event-Address:
[<00000000003bf12e>] arch_spin_lock_wait+0x56/0xb0
Suggested-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Fixes: ea127f9754 ("[PATCH] s390 (7/7): zfcp host adapter.") (tglx/history.git)
Cc: <stable@vger.kernel.org> #2.6.32+
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This was lost with commit 2c55b750a8
("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
but is necessary for problem determination, e.g. to see the
currently active zone set during automatic port scan.
For the large GPN_FT response (4 pages), save space by not dumping
any empty residual entries.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 2c55b750a8 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Alexey Ishchuk <aishchuk@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This information was lost with
commit a54ca0f62f
("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
but is required to debug e.g. invalid handle situations.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
While retaining the actual filtering according to trace level,
the following commits started to write such filtered records
with a hardcoded record level of 1 instead of the actual record level:
commit 250a1352b9
("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.")
commit a54ca0f62f
("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Now we can distinguish written records again for offline level filtering.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 250a1352b9 ("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.")
Fixes: a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
On a successful end of reopen port forced,
zfcp_erp_strategy_followup_success() re-uses the port erp_action
and the subsequent zfcp_erp_action_cleanup() now
sees ZFCP_ERP_SUCCEEDED with
erp_action->action==ZFCP_ERP_ACTION_REOPEN_PORT
instead of ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
but must not perform zfcp_scsi_schedule_rport_register().
We can detect this because the fresh port reopen erp_action
is in its very first step ZFCP_ERP_STEP_UNINITIALIZED.
Otherwise this opens a time window with unblocked rport
(until the followup port reopen recovery would block it again).
If a scsi_cmnd timeout occurs during this time window
fc_timed_out() cannot work as desired and such command
would indeed time out and trigger scsi_eh. This prevents
a clean and timely path failover.
This should not happen if the path issue can be recovered
on FC transport layer such as path issues involving RSCNs.
Also, unnecessary and repeated DID_IMM_RETRY for pending and
undesired new requests occur because internally zfcp still
has its zfcp_port blocked.
As follow-on errors with scsi_eh, it can cause,
in the worst case, permanently lost paths due to one of:
sd <scsidev>: [<scsidisk>] Medium access timeout failure. Offlining disk!
sd <scsidev>: Device offlined - not ready after error recovery
For fix validation and to aid future debugging with other recoveries
we now also trace (un)blocking of rports.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 5767620c38 ("[SCSI] zfcp: Do not unblock rport from REOPEN_PORT_FORCED")
Fixes: a2fa0aede0 ("[SCSI] zfcp: Block FC transport rports early on errors")
Fixes: 5f852be9e1 ("[SCSI] zfcp: Fix deadlock between zfcp ERP and SCSI")
Fixes: 338151e066 ("[SCSI] zfcp: make use of fc_remote_port_delete when target port is unavailable")
Fixes: 3859f6a248 ("[PATCH] zfcp: add rports to enable scsi_add_device to work again")
Cc: <stable@vger.kernel.org> #2.6.32+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Refactor direct debug level comparisons with the (internal) s390db->level
member. Use the debug_level_enabled() function instead.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the mapping of FCP device bus ID and corresponding subchannel
is modified while the Linux image is suspended, the resume of FCP
devices can fail. During resume, zfcp gets callbacks from cio regarding
the modified subchannels but they can be arbitrarily mixed with the
restore/resume callback. Since the cio callbacks would trigger
adapter recovery, zfcp could wakeup before the resume callback.
Therefore, ignore the cio callbacks regarding subchannels while
being suspended. We can safely do so, since zfcp does not deal itself
with subchannels. For problem determination purposes, we still trace the
ignored callback events.
The following kernel messages could be seen on resume:
kernel: <WWPN>: parent <FCP device bus ID> should not be sleeping
As part of adapter reopen recovery, zfcp performs auto port scanning
which can erroneously try to register new remote ports with
scsi_transport_fc and the device core code complains about the parent
(adapter) still sleeping.
kernel: zfcp.3dff9c: <FCP device bus ID>:\
Setting up the QDIO connection to the FCP adapter failed
<last kernel message repeated 3 more times>
kernel: zfcp.574d43: <FCP device bus ID>:\
ERP cannot recover an error on the FCP device
In such cases, the adapter gave up recovery and remained blocked along
with its child objects: remote ports and LUNs/scsi devices. Even the
adapter shutdown as part of giving up recovery failed because the ccw
device state remained disconnected. Later, the corresponding remote
ports ran into dev_loss_tmo. As a result, the LUNs were erroneously
not available again after resume.
Even a manually triggered adapter recovery (e.g. sysfs attribute
failed, or device offline/online via sysfs) could not recover the
adapter due to the remaining disconnected state of the corresponding
ccw device.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.32+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This patch is the final cleanup of the redesign from the zfcp tracing.
Structures and elements which were used by multiple areas of the
former debug tracing are now changed to the new scheme.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch is the continuation to redesign the zfcp tracing to a more
straight-forward and easy to extend scheme.
This patch deals with all trace records of the zfcp SCSI area.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch is the continuation to redesign the zfcp tracing to a more
straight-forward and easy to extend scheme.
This patch deals with all trace records of the zfcp HBA area.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch is the continuation to redesign the zfcp tracing to a more
straight-forward and easy to extend scheme.
This patch deals with all trace records of the zfcp SAN area.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The tracing environment of the zfcp LLD has become very bulky and hard
to maintain. Small changes involve a large modification process which
is error-prone and not effective. This patch is the first of a set to
redesign the zfcp tracing to a more straight-forward and easy to
extend scheme. It removes all interpretation and visualization parts
and focuses on bare logging of the information.
This patch deals with all trace records of the zfcp error recovery.
Signed-off-by: Swen schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
With the change that drivers have to explicitly request the serial
number for SCSI commands, this field should not be part of the zfcp
traces. It is not worth the effort to request the serial number only
for tracing purposes, so simply remove this field from the debug
traces.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This is the large change to switch from using the data in
zfcp_unit to zfcp_scsi_dev. Keeping everything working requires doing
the switch in one piece. To ensure that no code keeps using the data
in zfcp_unit, this patch also removes the data from zfcp_unit that is
now being replaced with zfcp_scsi_dev.
For zfcp, the scsi_device together with zfcp_scsi_dev exist from the
call of slave_alloc to the call of slave_destroy. The data in
zfcp_scsi_dev is initialized in zfcp_scsi_slave_alloc and the LUN is
opened; the final shutdown for the LUN is run from slave_destroy.
Where the scsi_device or zfcp_scsi_dev is needed, the pointer to the
scsi_device is passed as function argument and inside the function
converted to the pointer to zfcp_scsi_dev; this avoids back and forth
conversion betweeen scsi_device and zfcp_scsi_dev.
While changing the function arguments from zfcp_unit to scsi_device,
the functions names are renamed form "unit" to "lun". This is to have
a seperation between zfcp_scsi_dev/LUN and the zfcp_unit; only code
referring to the remaining configuration information in zfcp_unit
struct uses "unit".
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Introduce support for DIF/DIX in zfcp: Report the capabilities for the
Scsi_host, map the protection data when issuing I/O requests and
handle the new error codes. Also add the fsf data_direction field to
the hba trace, it is useful information for debugging in that area.
This is an EXPERIMENTAL feature for now.
Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Move the decision which trace tag and trace level to use for the scsi
result trace to zfcp_dbf.h. zfcp_dbf_scsi_result is already an inline
function, so move the trace code there, simplifying the response
handling in zfcp_fsf.c.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
0 is a valid value for a LUN. It is slightly confusing to also see 0
in the trace entries relating to adapter and port. Change this to use
0xFFFFFFFFFFFFFFFF in the LUN field when the trace entry does not
relate to a LUN or unit.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Remove the unused payload field from the struct zfcp_dbf_san_record,
saving some space in the SAN trace.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Remove some redundancies in FC related code and trace:
- drop redundant data from SAN trace (local s_id that only changes
during link down, ls_code that is already part of payload, d_id in
ct response trace that is always the same as in ct request trace)
- use one common fsf struct to hold zfcp data for ct and els requests
- leverage common fsf struct for FC passthrough job data, allocate it
with dd_bsg_data for passthrough requests and unify common code for
ct and els passthrough request
- simplify callback handling in zfcp_fc
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Use common data structures for FCP CMND, FCP RSP and related
definitions and remove zfcp private definitions. Split the FCP CMND
setup and FCP RSP evaluation code in seperate functions. Use inline
functions to not negatively impact the I/O path.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Change the dbf data and functions to use the zfcp_dbf prefix
throughout the code. Also change the calls to dbf to use zfcp_dbf
instead of zfcp_adapter.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The default trace level is to only trace failed FSF commands. Thus it
is not necessary to collect trace data for most FSF commands, since
it will be thrown away later. Restructure the FSF/HBA trace
infrastructure to first check the trace level in a inline function and
only do the expensive data collection for matching trace levels.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The default trace level is to only trace failed SCSI commands. Thus it
is not necessary to collect trace data for most SCSI commands since it
will be thrown away later. Restructure the SCSI trace infrastructure
to first check the trace level in a inline function and only do the
expensive data collection for matching trace levels.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The struct zfcp_adapter includes everything related to the debug
traces. This introduces dependences between the definitions in
zfcp_def.h and zfcp_dbf.h. Move all debug related data structures to a
new data structure to break those dependencies and manage the debug
data in zfcp_dbf.[hc].
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The current number based id ERP logging is replaced by a string
based tag version. The benefit is an easier location of the code in
question and the removal of the lengthy array referencing the
individual messages.
The string (7 bytes) based version does not use more space since those
bytes were "used" anyway due to the alignment of the structure.
The encoding of the 7 byte string is as follows
[0-1] = filename
[2-5] = task/function
[6] = section
Due to the character of this string (fixed length) a string
termination is not required here.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Add the support to send CT and ELS requests as unchained FSF requests. This is
required for older hardware and was somehow omitted during the cleanup of the
FSF layer. The req_count and resp_count attributes are unused, so remove them
instead of adding a special case for setting them. Also add debug data and a
warning, when the ct request hits a limit.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Acked-by: Martin Petermann <martin@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Fix multiple problems found in the hexdump data:
- length calculation was wrong, traces were incomplete
- FC payloads were dumped in different record than the output
function tried to read
- minor fixes in output
- allow complete RSCN traces (up to 1024 bytes according to spec)
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Now that we removed the long messages for the bit error threshold
data, put the data in the hba trace. This way, we get a short warning
for the threshold event from the hardware and have the data in the
trace for further analysis.
Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
There is no need to pack data structures which describe the
contents of records in the new recovery trace.
lcrash currently depends on the binary format for the other traces,
removing the packed attribute from all traces would break trace
debugging with lcrash.
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Store the index of the buffer in the inbound queue used to report
request completion in trace record for request coompletion.
This piece of information allows to better compare qdio and zfcp traces.
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
sbal_last is more appropriate, because it matches sbal_first.
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This field is not needed, because it designates an index with a fix offset
from sbal_first. It's name is confusing anyway.
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
as seen in linux-next tree:
drivers/s390/scsi/zfcp_dbf.c: In function ‘zfcp_rec_dbf_event_thread’:
drivers/s390/scsi/zfcp_dbf.c:697: warning: passing argument 1 of ‘atomic_read’
from incompatible pointer type
Caused by recent git commit:
commit 348447e857
Author: Martin Peschke <mp3@de.ibm.com>
Date: Thu Mar 27 14:22:01 2008 +0100
[SCSI] zfcp: Add trace records for recovery thread and its queues
We are not supposed to poke inside semaphore.
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Saving on line breaks, improving readability, by shortening excessive
function names and identifiers, by simplifying some functions call
chains, and by simplifying nesting of some data structure.
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Unclutter the global zfcp_def.h header. Move everything required to
call into the debug feature to a new header file.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Steffen Maier