Commit Graph

3959 Commits

Author SHA1 Message Date
Jens Remus 16dad27988 scsi: zfcp: enhance comments on fc_link_speed and supported_speed
The comment on fsf_qtcb_bottom_port.supported_speed did read as if the field
can only assume one of two possible values (i.e. 0x1 for 1 GBit/s or 0x2 for
2 GBit/s). This is not true for two reasons: first it is a flag field and
can thus assume any combination and second there are meanwhile more speeds.

Clarify comment on fsf_qtcb_bottom_port.supported_speed and add a comment to
fsf_qtcb_bottom_config.fc_link_speed.

Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Acked-by: Benjamin Block <bblock@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:17 -04:00
Jens Remus 6e2e490080 scsi: zfcp: add port speed capabilities
Add port speed capabilities as defined in FC-LS RPSC ELS that have a
counterpart FC_PORTSPEED_* defined in scsi/scsi_transport_fc.h.

Suggested-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Acked-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:16 -04:00
Jens Remus 9e156c54ac scsi: zfcp: assert that the ERP lock is held when tracing a recovery trigger
Otherwise iterating with list_for_each() over the adapter->erp_ready_head
and adapter->erp_running_head lists can lead to an infinite loop. See commit
"zfcp: fix infinite iteration on erp_ready_head list".

The run-time check is only performed for debug kernels which have the kernel
lock validator enabled. Following is an example of the warning that is
reported, if the ERP lock is not held when calling zfcp_dbf_rec_trig():

WARNING: CPU: 0 PID: 604 at drivers/s390/scsi/zfcp_dbf.c:288 zfcp_dbf_rec_trig+0x172/0x188
Modules linked in: ...
CPU: 0 PID: 604 Comm: kworker/u128:3 Not tainted 4.16.0-... #1
Hardware name: IBM 2964 N96 702 (z/VM 6.4.0)
Workqueue: zfcp_q_0.0.1906 zfcp_scsi_rport_work
Krnl PSW : 00000000330fdbf9 00000000367e9728 (zfcp_dbf_rec_trig+0x172/0x188)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
Krnl GPRS: 00000000c57a5d99 3288200000000000 0000000000000000 000000006cc82740
           00000000009d09d6 0000000000000000 00000000000000ff 0000000000000000
           0000000000000000 0000000000e1b5fe 000000006de01d38 0000000076130958
           000000006cc82548 000000006de01a98 00000000009d09d6 000000006a6d3c80
Krnl Code: 00000000009d0ad2: eb7ff0b80004        lmg        %r7,%r15,184(%r15)
           00000000009d0ad8: c0f4000d7dd0        brcl       15,b80678
          #00000000009d0ade: a7f40001            brc        15,9d0ae0
          >00000000009d0ae2: a7f4ff7d            brc        15,9d09dc
           00000000009d0ae6: e340f0f00004        lg         %r4,240(%r15)
           00000000009d0aec: eb7ff0b80004        lmg        %r7,%r15,184(%r15)
           00000000009d0af2: 07f4                bcr        15,%r4
           00000000009d0af4: 0707                bcr        0,%r7
Call Trace:
([<00000000009d09d6>] zfcp_dbf_rec_trig+0x66/0x188)
 [<00000000009dd740>] zfcp_scsi_rport_work+0x98/0x190
 [<0000000000169b34>] process_one_work+0x3d4/0x6f8
 [<000000000016a08a>] worker_thread+0x232/0x418
 [<000000000017219e>] kthread+0x166/0x178
 [<0000000000b815ea>] kernel_thread_starter+0x6/0xc
 [<0000000000b815e4>] kernel_thread_starter+0x0/0xc
2 locks held by kworker/u128:3/604:
 #0:  ((wq_completion)name){+.+.}, at: [<0000000082af1024>] process_one_work+0x1dc/0x6f8
 #1:  ((work_completion)(&port->rport_work)){+.+.}, at: [<0000000082af1024>] process_one_work+0x1dc/0x6f8
Last Breaking-Event-Address:
 [<00000000009d0ade>] zfcp_dbf_rec_trig+0x16e/0x188
---[ end trace b2f4020572e2c124 ]---

Suggested-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:16 -04:00
Steffen Maier 6919298c98 scsi: zfcp: cleanup indentation for posting FC events
I just happened to see the function header indentation of
zfcp_fc_enqueue_event() and I picked some more from checkpatch:

$ checkpatch.pl --strict -f drivers/s390/scsi/zfcp_fc.c
...
CHECK: Alignment should match open parenthesis
 #113: FILE: drivers/s390/scsi/zfcp_fc.c:113:
+		fc_host_post_event(adapter->scsi_host, fc_get_event_number(),
+				event->code, event->data);

CHECK: Blank lines aren't necessary before a close brace '}'
 #118: FILE: drivers/s390/scsi/zfcp_fc.c:118:
+
+}
...

The change complements v2.6.36 commit 2d1e547f75 ("[SCSI] zfcp: Post
events through FC transport class").

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:15 -04:00
Steffen Maier 35e9111a1e scsi: zfcp: support SCSI_ADAPTER_RESET via scsi_host sysfs attribute host_reset
Make use of feature introduced with v3.2 commit 2944369144 ("[SCSI] scsi:
Added support for adapter and firmware reset").  The common code interface
was introduced for commit 95d31262b3 ("[SCSI] qla4xxx: Added support for
adapter and firmware reset").

$ echo adapter > /sys/class/scsi_host/host<N>/host_reset

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : scshr_y                SCSI sysfs host_reset yes
LUN            : 0xffffffffffffffff                     none (invalid)
WWPN           : 0x0000000000000000                     none (invalid)
D_ID           : 0x00000000                             none (invalid)
Adapter status : 0x4500050b
Port status    : 0x00000000                             none (invalid)
LUN status     : 0x00000000                             none (invalid)
Ready count    : 0x00000001
Running count  : 0x00000000
ERP want       : 0x04                   ZFCP_ERP_ACTION_REOPEN_ADAPTER
ERP need       : 0x04                   ZFCP_ERP_ACTION_REOPEN_ADAPTER

This is the common code equivalent to the zfcp-specific
&dev_attr_adapter_failed.attr in zfcp_sysfs_adapter_attrs.attrs[]:

$ echo 0 > /sys/bus/ccw/drivers/zfcp/<devbusid>/failed

The unsupported case returns EOPNOTSUPP:

$ echo firmware > /sys/class/scsi_host/host<N>/host_reset
-bash: echo: write error: Operation not supported

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : scshr_n                        SCSI sysfs host_reset no
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0xffffffff                             none (invalid)
SCSI LUN       : 0xffffffff                             none (invalid)
SCSI LUN high  : 0xffffffff                             none (invalid)
SCSI result    : 0xffffffa1                     -EOPNOTSUPP==-95
SCSI retries   : 0xff                                   none (invalid)
SCSI allowed   : 0xff                                   none (invalid)
SCSI scribble  : 0xffffffffffffffff                     none (invalid)
SCSI opcode    : ffffffff ffffffff ffffffff ffffffff    none (invalid)
FCP rsp inf cod: 0xff                                   none (invalid)
FCP rsp IU     : 00000000 00000000 00000000 00000000    none (invalid)
                 00000000 00000000

For any other invalid value, common code returns EINVAL without invoking
our callback:

$ echo foo > /sys/class/scsi_host/host<N>/host_reset
-bash: echo: write error: Invalid argument

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:15 -04:00
Steffen Maier b24bf22d72 scsi: zfcp: explicitly support initiator in scsi_host_template
While the default did already correctly print "Initiator" let's make it
explicit and convert zfcp to the feature.

$ cat /sys/class/scsi_host/host0/supported_mode
Initiator

$ cat /sys/class/scsi_host/host0/active_mode
Initiator

The default worked, because not setting the field has it initialized to zero
== MODE_UNKNOWN. scsi_host_alloc() sets shost->active_mode = MODE_INITIATOR
in this case. The sysfs accessor function show_shost_supported_mode()
assumes MODE_INITIATOR in this case.  This default behavior was introduced
with v2.6.24 commit 7a39ac3f25 ("[SCSI] make supported_mode default to
initiator.").  The feature flag was introduced with v2.6.24 commit
5dc2b89e12 ("[SCSI] add supported_mode and active_mode attributes to the
host").  So there was no release where zfcp would have shown "unknown".

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:14 -04:00
Steffen Maier 2fdd45fd20 scsi: zfcp: remove unused return values of ERP trigger functions
Since v2.6.27 commit 553448f6c4 ("[SCSI] zfcp: Message cleanup"), none of
the callers has been interested any more.  Values were not returned
consistently in all ERP trigger functions.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:14 -04:00
Steffen Maier 013af857d8 scsi: zfcp: zfcp_erp_action_exists() does only check for running
Simplify its signature to return boolean and rename it to
zfcp_erp_action_is_running() to indicate its actual unmodified semantics.
It has always been used like this since v2.6.0 history commit ea127f975424
("[PATCH] s390 (7/7): zfcp host adapter.").

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:13 -04:00
Steffen Maier cd4a186aaa scsi: zfcp: remove unused ERP enum values
All constant defines were introduced with v2.6.0 history commit ea127f975424
("[PATCH] s390 (7/7): zfcp host adapter.") and refactored into enums with
commit 287ac01acf ("[SCSI] zfcp: Cleanup code in zfcp_erp.c").

ZFCP_STATUS_ERP_DISMISSING and ZFCP_ERP_STEP_FSF_XCONFIG were never used.

v2.6.27 commit 287ac01acf ("[SCSI] zfcp: Cleanup code in zfcp_erp.c")
removed the use of ZFCP_ERP_ACTION_READY on refactoring
zfcp_erp_action_exists() to now only check adapter->erp_running_head but no
longer adapter->erp_ready_head. The same commit could have changed the
function return type from int to "enum zfcp_erp_act_state".
ZFCP_ERP_ACTION_READY was never used outside of zfcp_erp_action_exists().

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:12 -04:00
Steffen Maier d39eda54b7 scsi: zfcp: consistently use function name space prefix
I've been mixing up
zfcp_task_mgmt_function() [SCSI] and
zfcp_fsf_fcp_task_mgmt()  [FSF]
so often lately that I wanted to fix this.

SCSI changes complement v2.6.27 commit f76af7d7e3 ("[SCSI] zfcp: Cleanup
of code in zfcp_scsi.c").

While at it, also fixup the other inconsistencies elsewhere.

ERP changes complement v2.6.27 commit 287ac01acf ("[SCSI] zfcp: Cleanup
code in zfcp_erp.c") which introduced status_change_set().

FC changes complement v2.6.32 commit 6f53a2d2ec ("[SCSI] zfcp: Apply
common naming conventions to zfcp_fc").  by renaming a leftover introduced
with v2.6.27 commit cc8c282963 ("[SCSI] zfcp: Automatically attach remote
ports").

FSF changes fixup v2.6.32 commit a4623c467f ("[SCSI] zfcp: Improve request
allocation through mempools").  which replaced zfcp_fsf_alloc_qtcb()
introduced with v2.6.27 commit c41f8cbddd ("[SCSI] zfcp: zfcp_fsf
cleanup.").

SCSI fc_host statistics were introduced with v2.6.16 commit f6cd94b126
("[SCSI] zfcp: transport class adaptations").

SCSI fc_host port_state was introduced with v2.6.27 commit 85a82392fe
("[SCSI] zfcp: Add port_state attribute to sysfs").

SCSI rport setter for dev_loss_tmo was introduced with v2.6.18 commit
338151e066 ("[SCSI] zfcp: make use of fc_remote_port_delete when target
port is unavailable").

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:28:12 -04:00
Steffen Maier 5c750d58e9 scsi: zfcp: workqueue: set description for port work items with their WWPN as context
As a prerequisite, complement commit 3d1cb2059d ("workqueue: include
workqueue info when printing debug dump of a worker task") to be usable with
kernel modules by exporting the symbol set_worker_desc().  Current built-in
user was introduced with commit ef3b101925 ("writeback: set worker desc to
identify writeback workers in task dumps").

Can help distinguishing work items which do not have adapter scope.
Description is printed out with task dump for debugging on WARN, BUG, panic,
or magic-sysrq [show-task-states(t)].

Example:
$ echo 0 >| /sys/bus/ccw/drivers/zfcp/0.0.1880/0x50050763031bd327/failed &
$ echo 't' >| /proc/sysrq-trigger
$ dmesg
sysrq: SysRq : Show State
  task                        PC stack   pid father
...
zfcp_q_0.0.1880 S14640  2165      2 0x02000000
Call Trace:
([<00000000009df464>] __schedule+0xbf4/0xc78)
 [<00000000009df57c>] schedule+0x94/0xc0
 [<0000000000168654>] rescuer_thread+0x33c/0x3a0
 [<000000000016f8be>] kthread+0x166/0x178
 [<00000000009e71f2>] kernel_thread_starter+0x6/0xc
 [<00000000009e71ec>] kernel_thread_starter+0x0/0xc
no locks held by zfcp_q_0.0.1880/2165.
...
kworker/u512:2  D11280  2193      2 0x02000000
Workqueue: zfcp_q_0.0.1880 zfcp_scsi_rport_work [zfcp] (zrpd-50050763031bd327)
                                                        ^^^^^^^^^^^^^^^^^^^^^
Call Trace:
([<00000000009df464>] __schedule+0xbf4/0xc78)
 [<00000000009df57c>] schedule+0x94/0xc0
 [<00000000009e50c0>] schedule_timeout+0x488/0x4d0
 [<00000000001e425c>] msleep+0x5c/0x78                  >>test code only<<
 [<000003ff8008a21e>] zfcp_scsi_rport_work+0xbe/0x100 [zfcp]
 [<0000000000167154>] process_one_work+0x3b4/0x718
 [<000000000016771c>] worker_thread+0x264/0x408
 [<000000000016f8be>] kthread+0x166/0x178
 [<00000000009e71f2>] kernel_thread_starter+0x6/0xc
 [<00000000009e71ec>] kernel_thread_starter+0x0/0xc
2 locks held by kworker/u512:2/2193:
 #0:  (name){++++.+}, at: [<0000000000166f4e>] process_one_work+0x1ae/0x718
 #1:  ((&(&port->rport_work)->work)){+.+.+.}, at: [<0000000000166f4e>] process_one_work+0x1ae/0x718
...

=============================================
Showing busy workqueues and worker pools:
workqueue zfcp_q_0.0.1880: flags=0x2000a
  pwq 512: cpus=0-255 flags=0x4 nice=0 active=1/1
    in-flight: 2193:zfcp_scsi_rport_work [zfcp]
pool 512: cpus=0-255 flags=0x4 nice=0 hung=0s workers=4 idle: 5 2354 2311

Work items with adapter scope are already identified by the workqueue name
"zfcp_q_<devbusid>" and the work item function name.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:27:21 -04:00
Steffen Maier 674595d851 scsi: zfcp: decouple our scsi_eh callbacks from scsi_cmnd
Note: zfcp_scsi_eh_host_reset_handler() will be converted in a later patch.

zfcp_scsi_eh_device_reset_handler() now only depends on scsi_device.
zfcp_scsi_eh_target_reset_handler() now only depends on scsi_target.
All derive other objects from these intended callback arguments.

zfcp_scsi_eh_target_reset_handler() is special: The FCP channel requires a
valid LUN handle so we try to find ourselves a stand-in scsi_device as
suggested by Hannes Reinecke. If it cannot find a stand-in scsi device,
trace a record like the following (formatted with zfcpdbf from s390-tools):

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : tr_nosd        target reset, no SCSI device
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0x00000000     SCSI ID/target denoting scope
SCSI LUN       : 0xffffffff                             none (invalid)
SCSI LUN high  : 0xffffffff                             none (invalid)
SCSI result    : 0x00002003     field re-used for midlayer value: FAILED
SCSI retries   : 0xff                                   none (invalid)
SCSI allowed   : 0xff                                   none (invalid)
SCSI scribble  : 0xffffffffffffffff                     none (invalid)
SCSI opcode    : ffffffff ffffffff ffffffff ffffffff    none (invalid)
FCP rsp inf cod: 0xff                                   none (invalid)
FCP rsp IU     : 00000000 00000000 00000000 00000000    none (invalid)
                 00000000 00000000

Actually change the signature of zfcp_task_mgmt_function() used by
zfcp_scsi_eh_device_reset_handler() & zfcp_scsi_eh_target_reset_handler().
Since it was prepared in a previous patch, we only need to delete a local
auto variable which is now the intended argument.

Suggested-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier 42afc6527d scsi: zfcp: decouple TMFs from scsi_cmnd by using fc_block_rport
Intentionally retrieve the rport by walking SCSI common code objects
rather than zfcp_sdev->port->rport.

The latter is used for pairing the calls to fc_remote_port_add() and
fc_remote_port_delete(). [see v2.6.31 commit 379d6bf657 ("[SCSI] zfcp:
Add port only once to FC transport class")]

zfcp_scsi_rport_register() sets zfcp_port.rport to what
fc_remote_port_add() returned.
zfcp_scsi_rport_block() sets zfcp_port.rport = NULL after having called
fc_remote_port_delete().

Hence, while an rport is blocked (or in any subsequent state due to
scsi_transport_fc timeouts such as fast_io_fail_tmo or dev_loss_tmo),
zfcp_port.rport is NULL and cannot serve as argument to fc_block_rport().

During zfcp recovery, a just recovered zfcp_port can have the UNBLOCKED
status flag, but an async rport unblocking has only started via
zfcp_scsi_schedule_rport_register() in zfcp_erp_try_rport_unblock()
[see v4.10 commit 6f2ce1c6af ("scsi: zfcp: fix rport unblock race with
LUN recovery")] in zfcp_erp_action_cleanup(). Now zfcp_erp_wait() can
return. This would be sufficient to successfully send a TMF.
But the rport can still be blocked and zfcp_port.rport can still be NULL
until zfcp_port.rport_work was scheduled and has actually called
fc_remote_port_add() and assigned its return value to zfcp_port.rport.
We need an unblocked rport for a successful scsi_eh TUR.

Similarly, for a zfcp_port which has just lost its UNBLOCKED status flag,
the return of zfcp_erp_wait() can race with zfcp_port.rport_work queued
by zfcp_scsi_schedule_rport_block(). Therefore we cannot reliably access
zfcp_port.rport. However, we'd like to get fc_rport_block()'s opinion on
when fast_io_fail_tmo triggered. While we might use
flush_work(&port->rport_work) to sync with the work item, we can simply use
the other way to get an rport pointer.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier 26f5fa9d47 scsi: zfcp: decouple SCSI setup of TMF from scsi_cmnd
Actually change the signature of zfcp_fsf_fcp_task_mgmt().
Since it was prepared in the previous patch, we only need to delete
a local auto variable which is now the intended argument.

Prepare zfcp_fsf_fcp_task_mgmt's caller zfcp_task_mgmt_function()
to have its function body only depend on a scsi_device and derived objects.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier 39abb11aca scsi: zfcp: decouple FSF request setup of TMF from scsi_cmnd
In zfcp_fsf_fcp_task_mgmt() resolve the still old argument scsi_cmnd into
scsi_device very early and only depend on scsi_device and derived objects in
the function body.

This prepares to later change the function signature replacing the scsi_cmnd
argument with scsi_device.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier e0116c91c7 scsi: zfcp: split FCP_CMND IU setup between SCSI I/O and TMF again
This reverts commit 2443c8b23a ("[SCSI] zfcp: Merge FCP task management
setup with regular FCP command setup"), because this introduced a
dependency on the unsuitable SCSI command for scsi_eh / TMF.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier 266883f2f7 scsi: zfcp: decouple TMF response handler from scsi_cmnd
Originally, I planned for TMF handling to have different context data in
fsf_req->data depending on the TMF scope in fcp_cmnd->fc_tm_flags:

 * scsi_device if FCP_TMF_LUN_RESET,
 * zfcp_port if FCP_TMF_TGT_RESET.

However, the FCP channel requires a valid LUN handle so we now use
scsi_device as context data with any TMF for the time being.

Regular SCSI I/O FCP requests continue using scsi_cmnd as req->data.

Hence, the callers of zfcp_fsf_fcp_handler_common() must resolve req->data
and pass scsi_device as common context.  While at it, remove the detour
zfcp_sdev->port->adapter and use the more direct req->adapter as elsewhere
in this function already.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier 8221211863 scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd
The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary
command of potentially many that are in the eh queue to be processed.  The
command is only used to indirectly pass the TMF scope in terms of SCSI
ID/target and SCSI LUN for LUN reset.

Hence, zfcp had filled in SCSI trace record fields which do not really
belong to the TMF. This was confusing.

Therefore, refactor the TMF tracing to work without SCSI command.  Since the
FCP channel always requires a valid LUN handle, we use SCSI device as common
context for any TMF (even target reset).  To make it even clearer, we set
all bits to 1 for the fields, which do not belong to the TMF, to indicate
that these fields are invalid.

The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both
SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can
be NULL with TMFs. The new argument scsi_device is mandatory to carry
context, as well as SCSI ID/target and SCSI LUN in case of TMFs.

New example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : [lt]r_....
Request ID     : 0x<reqid>              ID of FSF FCP request with TM flag
                 For cases without FSF request: 0x0 for none (invalid)
SCSI ID        : 0x<scsi_id>            SCSI ID/target denoting scope
SCSI LUN       : 0x<scsi_lun>           SCSI LUN denoting scope
SCSI LUN high  : 0x<scsi_lun_high>      SCSI LUN denoting scope
SCSI result    : 0xffffffff                             none (invalid)
SCSI retries   : 0xff                                   none (invalid)
SCSI allowed   : 0xff                                   none (invalid)
SCSI scribble  : 0xffffffffffffffff                     none (invalid)
SCSI opcode    : ffffffff ffffffff ffffffff ffffffff    none (invalid)
FCP rsp inf cod: 0x00                   FCP_RSP info code of TMF
FCP rsp IU     : 00000000 00000000 00000100 00000000 ext FCP_RSP IU
                 00000000 00000008                   ext FCP_RSP IU
FCP rsp IU len : 32                                  FCP_RSP IU length
Payload time   : ...
FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU
                 00000000 00000008 00000000 00000000 full FCP_RSP IU

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier 6a76550841 scsi: zfcp: fix missing REC trigger trace on enqueue without ERP thread
Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : .......
LUN            : 0x...
WWPN           : 0x...
D_ID           : 0x...
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x...
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x0.                   ZFCP_ERP_ACTION_REOPEN_...
ERP need       : 0xc0                   ZFCP_ERP_ACTION_NONE

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier 8c3d20aada scsi: zfcp: fix missing REC trigger trace for all objects in ERP_FAILED
That other commit introduced an inconsistency because it would trace on
ERP_FAILED for all callers of port forced reopen triggers (not just
terminate_rport_io), but it would not trace on ERP_FAILED for all callers of
other ERP triggers such as adapter, port regular, LUN.

Therefore, generalize that other commit. zfcp_erp_action_enqueue() already
had two early outs which re-used the one zfcp_dbf_rec_trig() call.  All ERP
trigger functions finally run through zfcp_erp_action_enqueue().  So move
the special handling for ZFCP_STATUS_COMMON_ERP_FAILED into
zfcp_erp_action_enqueue() and add another early out with new trace marker
for pseudo ERP need in this case. This removes all early returns from all
ERP trigger functions so we always end up at zfcp_dbf_rec_trig().

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : .......
LUN            : 0x...
WWPN           : 0x...
D_ID           : 0x...
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x...
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x0.                   ZFCP_ERP_ACTION_REOPEN_...
ERP need       : 0xe0                   ZFCP_ERP_ACTION_FAILED

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:11 -04:00
Steffen Maier d70aab5592 scsi: zfcp: fix missing REC trigger trace on terminate_rport_io for ERP_FAILED
For problem determination we always want to see when we were invoked on the
terminate_rport_io callback whether we perform something or not.

Temporal event sequence of interest with a long fast_io_fail_tmo of 27 sec:

loose remote port

t   workqueue
[s] zfcp_q_<dev>       IRQ                 zfcperp<dev>

=== ================== =================== ============================

  0                    recv RSCN
                       q p.test_link_work
    block rport
     start fast_io_fail_tmo
    send ADISC ELS
  4                    recv ADISC fail
                       block zfcp_port
                                           port forced reopen
                                           send open port
 12                    recv open port fail
                                           q p.gid_pn_work
                                           zfcp_erp_wakeup
                                           (zfcp_erp_wait would return)
    GID_PN fail

Before this point, we got a SCSI trace with tag "sctrpi1" on fast_io_fail,
e.g. with the typical 5 sec setting.

    port.status |= ERP_FAILED

If fast_io_fail_tmo triggers after this point, we missed a SCSI trace.

    workqueue
    fc_dl_<host>
    ==================
 27 fc_timeout_fail_rport_io
    fc_terminate_rport_io
    zfcp_scsi_terminate_rport_io
    zfcp_erp_port_forced_reopen
    _zfcp_erp_port_forced_reopen
     if (port.status & ERP_FAILED)
      return;

Therefore, write a trace before above early return.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : sctrpi1                SCSI terminate rport I/O
LUN            : 0xffffffffffffffff                     none (invalid)
WWPN           : 0x<wwpn>
D_ID           : 0x<n_port_id>
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x00000000                             none (invalid)
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x03                   ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
ERP need       : 0xe0                   ZFCP_ERP_ACTION_FAILED

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:10 -04:00
Steffen Maier 96d9270499 scsi: zfcp: fix missing REC trigger trace on terminate_rport_io early return
get_device() and its internally used kobject_get() only return NULL if they
get passed NULL as argument. zfcp_get_port_by_wwpn() loops over
adapter->port_list so the iteration variable port is always non-NULL.
Struct device is embedded in struct zfcp_port so &port->dev is always
non-NULL. This is the argument to get_device().  However, if we get an
fc_rport in terminate_rport_io() for which we cannot find a match within
zfcp_get_port_by_wwpn(), the latter can return NULL.  v2.6.30 commit
70932935b6 ("[SCSI] zfcp: Fix oops when port disappears") introduced an
early return without adding a trace record for this case.  Even if we don't
need recovery in this case, for debugging we should still see that our
callback was invoked originally by scsi_transport_fc.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : sctrpin        SCSI terminate rport I/O, no zfcp port
LUN            : 0xffffffffffffffff                     none (invalid)
WWPN           : 0x<wwpn>               WWPN
D_ID           : 0x<n_port_id>          N_Port-ID
Adapter status : 0x...
Port status    : 0xffffffff             unknown (-1)
LUN status     : 0x00000000                             none (invalid)
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x03                   ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
ERP need       : 0xc0                   ZFCP_ERP_ACTION_NONE

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 70932935b6 ("[SCSI] zfcp: Fix oops when port disappears")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:10 -04:00
Steffen Maier 512857a795 scsi: zfcp: fix misleading REC trigger trace where erp_action setup failed
If a SCSI device is deleted during scsi_eh host reset, we cannot get a
reference to the SCSI device anymore since scsi_device_get returns !=0 by
design. Assuming the recovery of adapter and port(s) was successful,
zfcp_erp_strategy_followup_success() attempts to trigger a LUN reset for the
half-gone SCSI device. Unfortunately, it causes the following confusing
trace record which states that zfcp will do a LUN recovery as "ERP need" is
ZFCP_ERP_ACTION_REOPEN_LUN == 1 and equals "ERP want".

Old example trace record formatted with zfcpdbf from s390-tools:

Tag:           : ersfs_3 ERP, trigger, unit reopen, port reopen succeeded
LUN            : 0x<FCP_LUN>
WWPN           : 0x<WWPN>
D_ID           : 0x<N_Port-ID>
Adapter status : 0x5400050b
Port status    : 0x54000001
LUN status     : 0x40000000     ZFCP_STATUS_COMMON_RUNNING
                                but not ZFCP_STATUS_COMMON_UNBLOCKED as it
                                was closed on close part of adapter reopen
ERP want       : 0x01
ERP need       : 0x01           misleading

However, zfcp_erp_setup_act() returns NULL as it cannot get the reference.
Hence, zfcp_erp_action_enqueue() takes an early goto out and _NO_ recovery
actually happens.

We always do want the recovery trigger trace record even if no erp_action
could be enqueued as in this case. For other cases where we did not enqueue
an erp_action, 'need' has always been zero to indicate this. In order to
indicate above goto out, introduce an eyecatcher "flag" to mark the "ERP
need" as 'not needed' but still keep the information which erp_action type,
that zfcp_erp_required_act() had decided upon, is needed.  0xc_ is chosen to
be visibly different from 0x0_ in "ERP want".

New example trace record formatted with zfcpdbf from s390-tools:

Tag:           : ersfs_3 ERP, trigger, unit reopen, port reopen succeeded
LUN            : 0x<FCP_LUN>
WWPN           : 0x<WWPN>
D_ID           : 0x<N_Port-ID>
Adapter status : 0x5400050b
Port status    : 0x54000001
LUN status     : 0x40000000
ERP want       : 0x01
ERP need       : 0xc1           would need LUN ERP, but no action set up
                   ^

Before v2.6.38 commit ae0904f60f ("[SCSI] zfcp: Redesign of the debug
tracing for recovery actions.") we could detect this case because the
"erp_action" field in the trace was NULL. The rework removed erp_action as
argument and field from the trace.

This patch here is for tracing. A fix to allow LUN recovery in the case at
hand is a topic for a separate patch.

See also commit fdbd1c5e27 ("[SCSI] zfcp: Allow running unit/LUN shutdown
without acquiring reference") for a similar case and background info.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: ae0904f60f ("[SCSI] zfcp: Redesign of the debug tracing for recovery actions.")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:10 -04:00
Steffen Maier 81979ae63e scsi: zfcp: fix missing SCSI trace for retry of abort / scsi_eh TMF
We already have a SCSI trace for the end of abort and scsi_eh TMF. Due to
zfcp_erp_wait() and fc_block_scsi_eh() time can pass between the start of
our eh callback and an actual send/recv of an abort / TMF request.  In order
to see the temporal sequence including any abort / TMF send retries, add a
trace before the above two blocking functions.  This supports problem
determination with scsi_eh and parallel zfcp ERP.

No need to explicitly trace the beginning of our eh callback, since we
typically can send an abort / TMF and see its HBA response (in the worst
case, it's a pseudo response on dismiss all of adapter recovery, e.g. due to
an FSF request timeout [fsrth_1] of the abort / TMF). If we cannot send, we
now get a trace record for the first "abrt_wt" or "[lt]r_wait" which denotes
almost the beginning of the callback.

No need to explicitly trace the wakeup after the above two blocking
functions because the next retry loop causes another trace in any case and
that is sufficient.

Example trace records formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : abrt_wt        abort, before zfcp_erp_wait()
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0x<scsi_id>
SCSI LUN       : 0x<scsi_lun>
SCSI LUN high  : 0x<scsi_lun_high>
SCSI result    : 0x<scsi_result_of_cmd_to_be_aborted>
SCSI retries   : 0x<retries_of_cmd_to_be_aborted>
SCSI allowed   : 0x<allowed_retries_of_cmd_to_be_aborted>
SCSI scribble  : 0x<req_id_of_cmd_to_be_aborted>
SCSI opcode    : <CDB_of_cmd_to_be_aborted>
FCP rsp inf cod: 0x..                                   none (invalid)
FCP rsp IU     : ...                                    none (invalid)

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : lr_wait        LUN reset, before zfcp_erp_wait()
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0x<scsi_id>
SCSI LUN       : 0x<scsi_lun>
SCSI LUN high  : 0x<scsi_lun_high>
SCSI result    : 0x...                                  unrelated
SCSI retries   : 0x..                                   unrelated
SCSI allowed   : 0x..                                   unrelated
SCSI scribble  : 0x...                                  unrelated
SCSI opcode    : ...                                    unrelated
FCP rsp inf cod: 0x..                                   none (invalid)
FCP rsp IU     : ...                                    none (invalid)

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 63caf367e1 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
Fixes: af4de36d91 ("[SCSI] zfcp: Block scsi_eh thread for rport state BLOCKED")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:10 -04:00
Steffen Maier df30781699 scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler
For problem determination we need to see whether and why we were successful
or not. This allows deduction of scsi_eh escalation.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : schrh_r        SCSI host reset handler result
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0xffffffff                             none (invalid)
SCSI LUN       : 0xffffffff                             none (invalid)
SCSI LUN high  : 0xffffffff                             none (invalid)
SCSI result    : 0x00002002     field re-used for midlayer value: SUCCESS
                                or in other cases: 0x2009 == FAST_IO_FAIL
SCSI retries   : 0xff                                   none (invalid)
SCSI allowed   : 0xff                                   none (invalid)
SCSI scribble  : 0xffffffffffffffff                     none (invalid)
SCSI opcode    : ffffffff ffffffff ffffffff ffffffff    none (invalid)
FCP rsp inf cod: 0xff                                   none (invalid)
FCP rsp IU     : 00000000 00000000 00000000 00000000    none (invalid)
                 00000000 00000000

v2.6.35 commit a1dbfddd02 ("[SCSI] zfcp: Pass return code from
fc_block_scsi_eh to scsi eh") introduced the first return with something
other than the previously hardcoded single SUCCESS return path.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: a1dbfddd02 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-18 11:22:10 -04:00
Linus Torvalds 6c21e4334a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull  more s390 updates from Martin Schwidefsky:
 "Three notable larger changes next to the usual bug fixing:

   - update the email addresses in MAINTAINERS for the s390 folks to use
     the simpler linux.ibm.com domain instead of the old
     linux.vnet.ibm.com

   - an update for the zcrypt device driver that removes some old and
     obsolete interfaces and add support for up to 256 crypto adapters

   - a rework of the IPL aka boot code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (23 commits)
  s390: correct nospec auto detection init order
  s390/zcrypt: Support up to 256 crypto adapters.
  s390/zcrypt: Remove deprecated zcrypt proc interface.
  s390/zcrypt: Remove deprecated ioctls.
  s390/zcrypt: Make ap init functions static.
  MAINTAINERS: update s390 maintainers email addresses
  s390/ipl: remove reipl_method and dump_method
  s390/ipl: correct kdump reipl block checksum calculation
  s390/ipl: remove non-existing functions declaration
  s390: assume diag308 set always works
  s390/ipl: avoid adding scpdata to cmdline during ftp/dvd boot
  s390/ipl: correct ipl parmblock valid checks
  s390/ipl: rely on diag308 store to get ipl info
  s390/ipl: move ipl_flags to ipl.c
  s390/ipl: get rid of ipl_ssid and ipl_devno
  s390/ipl: unite diag308 and scsi boot ipl blocks
  s390/ipl: ensure loadparm valid flag is set
  s390/qdio: lock device while installing IRQ handler
  s390/qdio: clear intparm during shutdown
  s390/ccwgroup: require at least one ccw device
  ...
2018-04-13 09:43:20 -07:00
Harald Freudenberger af4a72276d s390/zcrypt: Support up to 256 crypto adapters.
There was an artificial restriction on the card/adapter id
to only 6 bits but all the AP commands do support adapter
ids with 8 bit. This patch removes this restriction to 64
adapters and now up to 256 adapter can get addressed.

Some of the ioctl calls work on the max number of cards
possible (which was 64). These ioctls are now deprecated
but still supported. All the defines, structs and ioctl
interface declarations have been kept for compabibility.
There are now new ioctls (and defines for these) with an
additional '2' appended which provide the extended versions
with 256 cards supported.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-11 10:36:27 +02:00
Linus Torvalds 9f3a0941fb libnvdimm for 4.17
* A rework of the filesytem-dax implementation provides for detection of
   unmap operations (truncate / hole punch) colliding with in-progress
   device-DMA. A fix for these collisions remains a work-in-progress
   pending resolution of truncate latency and starvation regressions.
 
 * The of_pmem driver expands the users of libnvdimm outside of x86 and
   ACPI to describe an implementation of persistent memory on PowerPC with
   Open Firmware / Device tree.
 
 * Address Range Scrub (ARS) handling is completely rewritten to account for
   the fact that ARS may run for 100s of seconds and there is no platform
   defined way to cancel it. ARS will now no longer block namespace
   initialization.
 
 * The NVDIMM Namespace Label implementation is updated to handle label
   areas as small as 1K, down from 128K.
 
 * Miscellaneous cleanups and updates to unit test infrastructure.
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Merge tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "This cycle was was not something I ever want to repeat as there were
  several late changes that have only now just settled.

  Half of the branch up to commit d2c997c0f1 ("fs, dax: use
  page->mapping to warn...") have been in -next for several releases.
  The of_pmem driver and the address range scrub rework were late
  arrivals, and the dax work was scaled back at the last moment.

  The of_pmem driver missed a previous merge window due to an oversight.
  A sense of obligation to rectify that miss is why it is included for
  4.17. It has acks from PowerPC folks. Stephen reported a build failure
  that only occurs when merging it with your latest tree, for now I have
  fixed that up by disabling modular builds of of_pmem. A test merge
  with your tree has received a build success report from the 0day robot
  over 156 configs.

  An initial version of the ARS rework was submitted before the merge
  window. It is self contained to libnvdimm, a net code reduction, and
  passing all unit tests.

  The filesystem-dax changes are based on the wait_var_event()
  functionality from tip/sched/core. However, late review feedback
  showed that those changes regressed truncate performance to a large
  degree. The branch was rewound to drop the truncate behavior change
  and now only includes preparation patches and cleanups (with full acks
  and reviews). The finalization of this dax-dma-vs-trnucate work will
  need to wait for 4.18.

  Summary:

   - A rework of the filesytem-dax implementation provides for detection
     of unmap operations (truncate / hole punch) colliding with
     in-progress device-DMA. A fix for these collisions remains a
     work-in-progress pending resolution of truncate latency and
     starvation regressions.

   - The of_pmem driver expands the users of libnvdimm outside of x86
     and ACPI to describe an implementation of persistent memory on
     PowerPC with Open Firmware / Device tree.

   - Address Range Scrub (ARS) handling is completely rewritten to
     account for the fact that ARS may run for 100s of seconds and there
     is no platform defined way to cancel it. ARS will now no longer
     block namespace initialization.

   - The NVDIMM Namespace Label implementation is updated to handle
     label areas as small as 1K, down from 128K.

   - Miscellaneous cleanups and updates to unit test infrastructure"

* tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (39 commits)
  libnvdimm, of_pmem: workaround OF_NUMA=n build error
  nfit, address-range-scrub: add module option to skip initial ars
  nfit, address-range-scrub: rework and simplify ARS state machine
  nfit, address-range-scrub: determine one platform max_ars value
  powerpc/powernv: Create platform devs for nvdimm buses
  doc/devicetree: Persistent memory region bindings
  libnvdimm: Add device-tree based driver
  libnvdimm: Add of_node to region and bus descriptors
  libnvdimm, region: quiet region probe
  libnvdimm, namespace: use a safe lookup for dimm device name
  libnvdimm, dimm: fix dpa reservation vs uninitialized label area
  libnvdimm, testing: update the default smart ctrl_temperature
  libnvdimm, testing: Add emulation for smart injection commands
  nfit, address-range-scrub: introduce nfit_spa->ars_state
  libnvdimm: add an api to cast a 'struct nd_region' to its 'struct device'
  nfit, address-range-scrub: fix scrub in-progress reporting
  dax, dm: allow device-mapper to operate without dax support
  dax: introduce CONFIG_DAX_DRIVER
  fs, dax: use page->mapping to warn if truncate collides with a busy page
  ext2, dax: introduce ext2_dax_aops
  ...
2018-04-10 10:25:57 -07:00
Harald Freudenberger 71cbbff8c4 s390/zcrypt: Remove deprecated zcrypt proc interface.
This patch removes the deprecated zcrypt proc interface.
It is outdated and deprecated and does not support the
latest 3 generations of CEX cards.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:39:01 +02:00
Harald Freudenberger 2a80786d47 s390/zcrypt: Remove deprecated ioctls.
This patch removes the old status calls which have been marked
as deprecated since at least 2 years now. There is no known
application or library relying on these ioctls any more.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:39:01 +02:00
Harald Freudenberger efda7adec7 s390/zcrypt: Make ap init functions static.
The ap init functions ap_module_init and ap_debug_init are
only used within ap_bus.c. Make these functions static and
do not declare them in any header file any more.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:39:01 +02:00
Vasily Gorbik d485235b00 s390: assume diag308 set always works
diag308 set has been available for many machine generations, and
alternative reipl code paths has not been exercised and seems to be
broken without noticing for a while now. So, cleaning up all obsolete
reipl methods except currently used ones, assuming that diag308 set
always works.

Also removing not longer needed reset callbacks.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:38:59 +02:00
Vasily Gorbik d08091ac96 s390/ipl: rely on diag308 store to get ipl info
For both ccw and fcp boot retrieve ipl info from ipl block received via
diag308 store. Old scsi ipl parm block handling and cio_get_iplinfo are
removed. Ipl type is deducted from ipl block (if valid).

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:38:59 +02:00
Julian Wiedmann 7eee12b44e s390/qdio: lock device while installing IRQ handler
During setup, qdio takes control of the presented ccw device and replaces
the device's IRQ handler with its own. To avoid any interference with
conccurent activity on the device, this should be done while holding the
device's lock.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:38:58 +02:00
Julian Wiedmann 89286320a2 s390/qdio: clear intparm during shutdown
During shutdown, qdio returns its ccw device back to control by the
upper-layer driver. But there is a remote chance that by the time where the
IRQ handler gets switched back, the interrupt for the preceding
ccw_device_{clear,halt} hasn't been presented yet.
Upper-layer drivers would then need to handle this IRQ - and since the IO
is issued with an intparm, it could very well be confused with whatever
intparm mechanism the driver uses itself (eg intparm == request address).

So when switching over the IRQ handler, also clear the intparm and have
upper-layer drivers deal with any such delayed interrupt as if it was
unsolicited.

Suggested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:38:58 +02:00
Julian Wiedmann ab7efda477 s390/ccwgroup: require at least one ccw device
ccwgroup_create_dev() derives the gdev's device name from gdev->cdev[0],
so make sure that this reference is valid.

For robustness only, all current ccwgroup drivers get this right.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:38:57 +02:00
Harald Freudenberger 2c957a8ad4 s390/zcrypt: remove unused functions and declarations
The AP bus code is not available as kernel module any more.
There was some leftover code dealing with kernel module
exit which has been removed with this patch.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:38:57 +02:00
Dan Williams e13e75b86e Merge branch 'for-4.17/dax' into libnvdimm-for-next 2018-04-09 10:50:17 -07:00
Linus Torvalds becdce1c66 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:

 - Improvements for the spectre defense:
    * The spectre related code is consolidated to a single file
      nospec-branch.c
    * Automatic enable/disable for the spectre v2 defenses (expoline vs.
      nobp)
    * Syslog messages for specve v2 are added
    * Enable CONFIG_GENERIC_CPU_VULNERABILITIES and define the attribute
      functions for spectre v1 and v2

 - Add helper macros for assembler alternatives and use them to shorten
   the code in entry.S.

 - Add support for persistent configuration data via the SCLP Store Data
   interface. The H/W interface requires a page table that uses 4K pages
   only, the code to setup such an address space is added as well.

 - Enable virtio GPU emulation in QEMU. To do this the depends
   statements for a few common Kconfig options are modified.

 - Add support for format-3 channel path descriptors and add a binary
   sysfs interface to export the associated utility strings.

 - Add a sysfs attribute to control the IFCC handling in case of
   constant channel errors.

 - The vfio-ccw changes from Cornelia.

 - Bug fixes and cleanups.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (40 commits)
  s390/kvm: improve stack frame constants in entry.S
  s390/lpp: use assembler alternatives for the LPP instruction
  s390/entry.S: use assembler alternatives
  s390: add assembler macros for CPU alternatives
  s390: add sysfs attributes for spectre
  s390: report spectre mitigation via syslog
  s390: add automatic detection of the spectre defense
  s390: move nobp parameter functions to nospec-branch.c
  s390/cio: add util_string sysfs attribute
  s390/chsc: query utility strings via fmt3 channel path descriptor
  s390/cio: rename struct channel_path_desc
  s390/cio: fix unbind of io_subchannel_driver
  s390/qdio: split up CCQ handling for EQBS / SQBS
  s390/qdio: don't retry EQBS after CCQ 96
  s390/qdio: restrict buffer merging to eligible devices
  s390/qdio: don't merge ERROR output buffers
  s390/qdio: simplify math in get_*_buffer_frontier()
  s390/decompressor: trim uncompressed image head during the build
  s390/crypto: Fix kernel crash on aes_s390 module remove.
  s390/defkeymap: fix global init to zero
  ...
2018-04-09 09:04:10 -07:00
Linus Torvalds 3526dd0c78 for-4.17/block-20180402
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Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:
 "It's a pretty quiet round this time, which is nice. This contains:

   - series from Bart, cleaning up the way we set/test/clear atomic
     queue flags.

   - series from Bart, fixing races between gendisk and queue
     registration and removal.

   - set of bcache fixes and improvements from various folks, by way of
     Michael Lyle.

   - set of lightnvm updates from Matias, most of it being the 1.2 to
     2.0 transition.

   - removal of unused DIO flags from Nikolay.

   - blk-mq/sbitmap memory ordering fixes from Omar.

   - divide-by-zero fix for BFQ from Paolo.

   - minor documentation patches from Randy.

   - timeout fix from Tejun.

   - Alpha "can't write a char atomically" fix from Mikulas.

   - set of NVMe fixes by way of Keith.

   - bsg and bsg-lib improvements from Christoph.

   - a few sed-opal fixes from Jonas.

   - cdrom check-disk-change deadlock fix from Maurizio.

   - various little fixes, comment fixes, etc from various folks"

* tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits)
  blk-mq: Directly schedule q->timeout_work when aborting a request
  blktrace: fix comment in blktrace_api.h
  lightnvm: remove function name in strings
  lightnvm: pblk: remove some unnecessary NULL checks
  lightnvm: pblk: don't recover unwritten lines
  lightnvm: pblk: implement 2.0 support
  lightnvm: pblk: implement get log report chunk
  lightnvm: pblk: rename ppaf* to addrf*
  lightnvm: pblk: check for supported version
  lightnvm: implement get log report chunk helpers
  lightnvm: make address conversions depend on generic device
  lightnvm: add support for 2.0 address format
  lightnvm: normalize geometry nomenclature
  lightnvm: complete geo structure with maxoc*
  lightnvm: add shorten OCSSD version in geo
  lightnvm: add minor version to generic geometry
  lightnvm: simplify geometry structure
  lightnvm: pblk: refactor init/exit sequences
  lightnvm: Avoid validation of default op value
  lightnvm: centralize permission check for lightnvm ioctl
  ...
2018-04-05 14:27:02 -07:00
Linus Torvalds 3b24b83763 Kbuild updates for v4.17
- add a shell script to get Clang version
 
 - improve portability of build scripts
 
 - drop always-enabled CONFIG_THIN_ARCHIVE and remove unused code
 
 - rename built-in.o which is now thin archive to built-in.a
 
 - process clean/build targets one by one to get along with -j option
 
 - simplify ld-option
 
 - improve building with CONFIG_TRIM_UNUSED_KSYMS
 
 - define KBUILD_MODNAME even for objects shared among multiple modules
 
 - avoid linking multiple instances of same objects from composite objects
 
 - move <linux/compiler_types.h> to c_flags to include it only for C files
 
 - clean-up various Makefiles
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Merge tag 'kbuild-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - add a shell script to get Clang version

 - improve portability of build scripts

 - drop always-enabled CONFIG_THIN_ARCHIVE and remove unused code

 - rename built-in.o which is now thin archive to built-in.a

 - process clean/build targets one by one to get along with -j option

 - simplify ld-option

 - improve building with CONFIG_TRIM_UNUSED_KSYMS

 - define KBUILD_MODNAME even for objects shared among multiple modules

 - avoid linking multiple instances of same objects from composite
   objects

 - move <linux/compiler_types.h> to c_flags to include it only for C
   files

 - clean-up various Makefiles

* tag 'kbuild-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (29 commits)
  kbuild: get <linux/compiler_types.h> out of <linux/kconfig.h>
  kbuild: clean up link rule of composite modules
  kbuild: clean up archive rule of built-in.a
  kbuild: remove partial section mismatch detection for built-in.a
  net: liquidio: clean up Makefile for simpler composite object handling
  lib: zstd: clean up Makefile for simpler composite object handling
  kbuild: link $(real-obj-y) instead of $(obj-y) into built-in.a
  kbuild: rename real-objs-y/m to real-obj-y/m
  kbuild: move modname and modname-multi close to modname_flags
  kbuild: simplify modname calculation
  kbuild: fix modname for composite modules
  kbuild: define KBUILD_MODNAME even if multiple modules share objects
  kbuild: remove unnecessary $(subst $(obj)/, , ...) in modname-multi
  kbuild: Use ls(1) instead of stat(1) to obtain file size
  kbuild: link vmlinux only once for CONFIG_TRIM_UNUSED_KSYMS
  kbuild: move include/config/ksym/* to include/ksym/*
  kbuild: move CONFIG_TRIM_UNUSED_KSYMS code unneeded for external module
  kbuild: restore autoksyms.h touch to the top Makefile
  kbuild: move 'scripts' target below
  kbuild: remove wrong 'touch' in adjust_autoksyms.sh
  ...
2018-04-03 15:51:22 -07:00
Dan Williams 2080e88aec dax: introduce CONFIG_DAX_DRIVER
In support of allowing device-mapper to compile out idle/dead code when
there are no dax providers in the system, introduce the DAX_DRIVER
symbol. This is selected by all leaf drivers that device-mapper might be
layered on top. This allows device-mapper to conditionally 'select DAX'
only when a provider is present.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-04-03 05:41:19 -07:00
Sebastian Ott b9dd652499 s390/cio: add util_string sysfs attribute
Export utility strings as a chpid's binary sysfs attribute.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-28 08:38:22 +02:00
Sebastian Ott fcc6dd4b7b s390/chsc: query utility strings via fmt3 channel path descriptor
Add support for format 3 channel path descriptors and use them to
gather utility strings.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-26 16:13:16 +02:00
Sebastian Ott ded27d8d2e s390/cio: rename struct channel_path_desc
Rename struct channel_path_desc to struct channel_path_desc_fmt0
to fit the scheme. Provide a macro for the function wrappers that
gather this and related data from firmware.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-26 16:13:11 +02:00
Sebastian Ott 135a8b4ce5 s390/cio: fix unbind of io_subchannel_driver
If the io_subchannel_driver is unbound from a subchannel it bluntly kills
all I/O on the subchannel and sets the ccw_device state to not operable
before deregistering the ccw_device. However, for online devices we should
set the device offline (disband path groups etc.) which does not happen if
the device is in not oper state.

Simply deregister the ccw device - ccw_device_remove is smart enough to set
the device offline properly. If everything fails call io_subchannel_quiesce
afterwards as a safeguard.

Reported-by: Shalini Chellathurai Saroja <shalini@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-26 16:13:06 +02:00
Julian Wiedmann 88bf319fc2 s390/qdio: split up CCQ handling for EQBS / SQBS
Get rid of the confusing two-stage translation in a hot path, and only
handle CCQs that we anticipate for the respective command. Any
unexpected value (such as CCQ 97 (rc == 1) for SQBS) should be
considered a severe HW/driver bug, and traced as such.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-26 16:13:02 +02:00
Julian Wiedmann dae55b6fef s390/qdio: don't retry EQBS after CCQ 96
Immediate retry of EQBS after CCQ 96 means that we potentially misreport
the state of buffers inspected during the first EQBS call.

This occurs when
1. the first EQBS finds all inspected buffers still in the initial state
   set by the driver (ie INPUT EMPTY or OUTPUT PRIMED),
2. the EQBS terminates early with CCQ 96, and
3. by the time that the second EQBS comes around, the state of those
   previously inspected buffers has changed.

If the state reported by the second EQBS is 'driver-owned', all we know
is that the previous buffers are driver-owned now as well. But we can't
tell if they all have the same state. So for instance
- the second EQBS reports OUTPUT EMPTY, but any number of the previous
  buffers could be OUTPUT ERROR by now,
- the second EQBS reports OUTPUT ERROR, but any number of the previous
  buffers could be OUTPUT EMPTY by now.

Effectively, this can result in both over- and underreporting of errors.

If the state reported by the second EQBS is 'HW-owned', that doesn't
guarantee that the previous buffers have not been switched to
driver-owned in the mean time. So for instance
- the second EQBS reports INPUT EMPTY, but any number of the previous
  buffers could be INPUT PRIMED (or INPUT ERROR) by now.

This would result in failure to process pending work on the queue. If
it's the final check before yielding initiative, this can cause
a (temporary) queue stall due to IRQ avoidance.

Fixes: 25f269f173 ("[S390] qdio: EQBS retry after CCQ 96")
Cc: <stable@vger.kernel.org> #v3.2+
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-26 16:12:53 +02:00
Julian Wiedmann c11a3dfd6f s390/qdio: restrict buffer merging to eligible devices
Only attempt to merge PENDING into EMPTY buffers for devices where
the PENDING state is actually expected (ie. IQD with CQ).
This might speed up the hot path a little bit.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-26 16:12:48 +02:00
Julian Wiedmann 0cf1e05157 s390/qdio: don't merge ERROR output buffers
On an Output queue, both EMPTY and PENDING buffer states imply that the
buffer is ready for completion-processing by the upper-layer drivers.

So for a non-QEBSM Output queue, get_buf_states() merges mixed
batches of PENDING and EMPTY buffers into one large batch of EMPTY
buffers. The upper-layer driver (ie. qeth) later distuingishes PENDING
from EMPTY by inspecting the slsb_state for
QDIO_OUTBUF_STATE_FLAG_PENDING.

But the merge logic in get_buf_states() contains a bug that causes us to
erronously also merge ERROR buffers into such a batch of EMPTY buffers
(ERROR is 0xaf, EMPTY is 0xa1; so ERROR & EMPTY == EMPTY).
Effectively, most outbound ERROR buffers are currently discarded
silently and processed as if they had succeeded.

Note that this affects _all_ non-QEBSM device types, not just IQD with CQ.

Fix it by explicitly spelling out the exact conditions for merging.

For extracting the "get initial state" part out of the loop, this relies
on the fact that get_buf_states() is never called with a count of 0. The
QEBSM path already strictly requires this, and the two callers with
variable 'count' make sure of it.

Fixes: 104ea556ee ("qdio: support asynchronous delivery of storage blocks")
Cc: <stable@vger.kernel.org> #v3.2+
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-26 16:12:33 +02:00