The global config_lock was used to protect the configuration organized
in independent lists. It is not necessary to have a lock on driver
level for this purpose. This patch replaces the global config_lock
with a set of local list locks.
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>
Adapt the change_queue_depth callback in zfcp for the new reason
parameter. Simply pass each call back to the SCSI midlayer, there are
no resource adjustments necessary for zfcp.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Removes check for (depth <= default_depth) in case of
SCSI_QDEPTH_RAMP_UP call back, not needed after added
max_queue_depth per sdev.
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch modifies scsi_host_template->change_queue_depth so that
it takes an argument indicating why it is being called. This will be
used so that if a LLD needs to do some extra processing when
handling queue fulls or later ramp ups, it can do so.
This is a simple port of the drivers setting a change_queue_depth
callback. In the patch I just have these LLDs adjust the queue depth
if the user was requesting it.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
[Vasu.Dev: v2
Also converted pmcraid_change_queue_depth and then verified
all modules compile using "make allmodconfig" for any new build
warnings on X86_64.
Updated original description after combing two original
patches from Mike to make this patch git bisectable.]
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
[jejb: fixed up 53c700]
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
When configuring a LUN for use in zfcp, flush the SCSI work to ensure
the SCSI device has been created before returning. This means that a
configuration procedure can run these commands in a script and the
SCSI device is available immediately after the unit_add:
echo 1 > /sys/bus/ccw/drivers/zfcp/0.0.181d/online
echo 0x401040C300000000 > \
/sys/bus/ccw/drivers/zfcp/0.0.181d/0x500507630313c562/unit_add
lsscsi
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>
Add HZ since the start_timer function expects jiffies, not seconds.
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>
After opening a remote port zfcp checks if the WWPN returned in the
PLOGI maches the WWPN of the port that should have been opened. On a
mismatch zfcp assumes that the DID just changed, queries the FC
nameserver and tries again. If the situation persists the erp will
give up.
With this strategy, if the remote port always returns the wrong PLOGI
data, the remote port will not be opened. Introduce a warning, so that
the system administrator knows why the remote port is not being opened
and to have a pointer to investigate the problem on the storage
system.
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>
For ports, zfcp gets the DID from the FC nameserver and tries to open
the port. If the open succeeds, zfcp compares the WWPN from the
nameserver with the WWPN in the PLOGI payload. In case of a mismatch,
zfcp assumes that the DID of the port just changed and we opened the
wrong port. This means that zfcp has to forget the DID, lookup the DID
again and retry.
This error case had a problem that zfcp forgets the DID, but never
looks up a new one, stalling the ERP in this case. Fix this by
triggering the DID lookup and properly exit from the ERP. The DID
lookup will trigger a new ERP action.
Also ensure when trying to open the port again with the new DID, first
close the open port, even in the NOESC case.
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The pointer that is allocated with kmalloc() is passed to strsep()
which modifies it. Later on the modified pointer value will be passed
to kfree. Save the original pointer and pass that one to kfree
instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Running chchp --vary 0 and chccwdev -d on a FCP device with scsi
devices attached can lead to this thread hanging:
================================================================
STACK TRACE FOR TASK: 0x2fbfcc00 (kslowcrw)
STACK:
0 schedule+1136 [0x45f99c]
1 schedule_timeout+534 [0x46054e]
2 wait_for_common+374 [0x45f442]
3 blk_execute_rq+160 [0x217a2c]
4 scsi_execute+278 [0x26daf2]
5 scsi_execute_req+150 [0x26dc86]
6 sd_sync_cache+138 [0x28460a]
7 sd_shutdown+130 [0x28486a]
8 sd_remove+104 [0x284c84]
9 __device_release_driver+152 [0x257430]
10 device_release_driver+56 [0x2575c8]
11 bus_remove_device+214 [0x25672a]
12 device_del+352 [0x25456c]
13 __scsi_remove_device+108 [0x272630]
14 scsi_remove_device+66 [0x2726ba]
15 zfcp_ccw_remove+824 [0x335558]
16 ccw_device_remove+62 [0x2b3f2a]
17 __device_release_driver+152 [0x257430]
18 device_release_driver+56 [0x2575c8]
19 bus_remove_device+214 [0x25672a]
20 device_del+352 [0x25456c]
21 ccw_device_unregister+92 [0x2b48c4]
22 io_subchannel_remove+108 [0x2b4950]
23 css_remove+62 [0x2af7ee]
24 __device_release_driver+152 [0x257430]
25 device_release_driver+56 [0x2575c8]
26 bus_remove_device+214 [0x25672a]
27 device_del+352 [0x25456c]
28 device_unregister+38 [0x25464a]
29 css_sch_device_unregister+68 [0x2af97c]
30 ccw_device_call_sch_unregister+78 [0x2b581e]
31 worker_thread+604 [0x69eb0]
32 kthread+154 [0x6ff42]
33 kernel_thread_starter+6 [0x1c952]
================================================================
The problem is that the chchp --vary 0 leads to zfcp first calling
fc_remote_port_delete which blocks all scsi devices on the remote
port. Calling scsi_remove_device later lets the sd driver issue a
SYNCHRONIZE_CACHE command. This command stays on the "stopped" request
requeue because the SCSI device is blocked. Fix this by first removing
the scsi and fc hosts which removes all scsi devices and do not use
scsi_remove_device.
Reviewed-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>
=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.31-39.x.20090917-s390xdefault #1
-------------------------------------------------------
kslowcrw/83 is trying to acquire lock:
(&adapter->scan_work){+.+.+.}, at: [<0000000000169c5c>] __cancel_work_timer+0x64/0x3d4
but task is already holding lock:
(&zfcp_data.config_mutex){+.+.+.}, at: [<00000000004671ea>] zfcp_ccw_remove+0x66/0x384
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&zfcp_data.config_mutex){+.+.+.}:
[<0000000000189962>] __lock_acquire+0xe26/0x1834
[<000000000018a4b6>] lock_acquire+0x146/0x178
[<000000000058cb5a>] mutex_lock_nested+0x82/0x3ec
[<0000000000477170>] zfcp_fc_scan_ports+0x3ec/0x728
[<0000000000168e34>] worker_thread+0x278/0x3a8
[<000000000016ff08>] kthread+0x9c/0xa4
[<0000000000109ebe>] kernel_thread_starter+0x6/0xc
[<0000000000109eb8>] kernel_thread_starter+0x0/0xc
-> #0 (&adapter->scan_work){+.+.+.}:
[<0000000000189e60>] __lock_acquire+0x1324/0x1834
[<000000000018a4b6>] lock_acquire+0x146/0x178
[<0000000000169c9a>] __cancel_work_timer+0xa2/0x3d4
[<0000000000465cb2>] zfcp_adapter_dequeue+0x32/0x14c
[<00000000004673e4>] zfcp_ccw_remove+0x260/0x384
[<00000000004250f6>] ccw_device_remove+0x42/0x1ac
[<00000000003cb6be>] __device_release_driver+0x9a/0x10c
[<00000000003cb856>] device_release_driver+0x3a/0x4c
[<00000000003ca94c>] bus_remove_device+0xcc/0x114
[<00000000003c8506>] device_del+0x162/0x21c
[<0000000000425ff2>] ccw_device_unregister+0x5e/0x7c
[<000000000042607e>] io_subchannel_remove+0x6e/0x9c
[<000000000041ff9a>] css_remove+0x3e/0x7c
[<00000000003cb6be>] __device_release_driver+0x9a/0x10c
[<00000000003cb856>] device_release_driver+0x3a/0x4c
[<00000000003ca94c>] bus_remove_device+0xcc/0x114
[<00000000003c8506>] device_del+0x162/0x21c
[<00000000003c85e8>] device_unregister+0x28/0x38
[<0000000000420152>] css_sch_device_unregister+0x46/0x58
[<00000000004276a6>] io_subchannel_sch_event+0x28e/0x794
[<0000000000420442>] css_evaluate_known_subchannel+0x46/0xd0
[<0000000000420ebc>] slow_eval_known_fn+0x88/0xa0
[<00000000003caffa>] bus_for_each_dev+0x7e/0xd0
[<000000000042188c>] for_each_subchannel_staged+0x6c/0xd4
[<0000000000421a00>] css_slow_path_func+0x54/0xd8
[<0000000000168e34>] worker_thread+0x278/0x3a8
[<000000000016ff08>] kthread+0x9c/0xa4
[<0000000000109ebe>] kernel_thread_starter+0x6/0xc
[<0000000000109eb8>] kernel_thread_starter+0x0/0xc
cancel_work_sync is called while holding the config_mutex. But the
work that is being cancelled or flushed also uses the config_mutex.
Fix the resulting deadlock possibility by calling cancel_work_sync
earlier without holding the mutex. The best place to do is is after
offlining the device. No new port scan work will be scheduled for the
offline device, so this is a safe place to call cancel_work_sync.
Reviewed-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>
With the change that the zfcp_adapter struct is only allocated when
the device is set online, the shutdown handler has to check for a
non-existing zfcp_adapter struct. On the other hand, this check is not
necessary in the offline callback, since an online device has the
zfcp_adapter allocated and we go through the offline callback before
removing the ccw device.
Reviewed-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>
With the change for delaying the allocation of zfcp_adapter, the
initial device parameter function has to first call
ccw_device_set_online which allocates the zfcp_adapter structure.
Change this and adapt the cfdc part accordingly.
Reviewed-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>
The common initialization of ct/gs and els requests missed the
initialization of unchained requests. Fix this by moving the common
parts to a place that is called for all ct/gs and els requests.
Reviewed-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>
Remove expensive ktime_get()/ktime_us_delta() functions from the hot
path and use get_clock_monotonic() instead. This elimates seven
function calls and avoids a lot of unnecessary calculations.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The timestamp calculation used for s390dbf output is the same in a
private zfcp function and in debug.c. Replace both with a common
inline function.
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>
dev_set_name tries to allocate memory, so check the return value for
allocation failures. After dev_set_name succeeds, call device_register
as next step to be able to use put_device during error handling.
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>
Don't use kfree directly after device registration started.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
The config semaphore is only used as a mutex, so replace it with a
simple mutex.
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>
So far, zfcp allocated all resources required for FCP
adapters/subchannels when the device was discovered in the ccw_probe
callback. If there are lots of unused FCP subchannels attached to a
system, this is a waste of resources. To alleviate this, defer the
resource allocation to the first call to ccw_set_online. To avoid
disruptions during possible following calls to ccw_set_offline and
then ccw_set_online, keep the adapter resources until the device is
finally being removed via ccw_remove. While doing this, also manage
the zfcp erp thread together with all other adapter resources in
zfcp_adapter_enqueue/dequeue.
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 recommendation for a timeout of 2 * R_A_TOV is the same for ct/gs
and els requests, so set it in the common function used for
initializing both request types. Besides, the timer inside zfcp should
only run longer than the timeout set for the channel, so 10 seconds
more should be enough (instead of 60 seconds).
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>
Switch the creation of the zfcp erp thread from the deprecated
kernel_thread API to the kthread API. This allows also the removal of
some flags in zfcp since the kthread API handles thread creation and
shutdown internally. To allow the usage of the kthread_stop function,
replace the erp ready semaphore with a waitqueue for waiting until erp
actions arrive on the ready queue.
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 fc_rport structure reserves a reference where a LLD can put
information required in a situation where the fc transport class is
triggering LLD callbacks. The zfcp driver was using this variable
directly which is discouraged. This patch solves this issue by making
this reference unnecessary. In addition the dev_loss_tmo callback is
removed, it is not required: zfcp does not access the fc_rport after
calling fc_remote_port_delete.
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>
Update the Fibre Channel related code to use the zfcp_fc prefix.
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>
Extract independent data structures and introduce common _setup and
_destroy routines for QDIO and Fibre Channel related data structures
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>
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>
Don't let the erp wait for gid_pn requests to complete. Instead, queue
the gid_pn work, exit erp and let the finished gid_pn work trigger a
new port reopen.
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 zfcp_adapter structure was growing over time to a size of almost
one memory page. To reduce the size of the data structure and to
seperate different layers, put all qdio related data in the new
zfcp_qdio data structure.
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>
Split all qdio related attributes out of zfcp_fsf_req and put it in
new structure.
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>
Remove the global driver work queue and replace it with a workqueue
local to the adapter. The usage of this workqueue makes this the
correct place for the structure. In addition multiple adapters won't
block each other due to the serialization of the queued work.
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 flag ZFCP_REQ_AUTO_CLEANUP was useless as the
ZFCP_STATUS_FSFREQ_CLEANUP flag is there for exactly the same purpose.
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>
Remove the special case for NO_QTCB requests and optimize the
mempool and cache processing for fsfreqs. Especially use seperate
mempools for the zfcp_fsf_req and zfcp_qtcb structs.
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 combination wait_queue/wakeup in conjunction with the flag
ZFCP_STATUS_FSFREQ_COMPLETED to signal the completion of an fsfreq
was not race-safe and can be better solved by a completion.
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>
There is no need for the QDIO layer to have knowledge or do things
wich are done better by the FSF layer and vice versa. Straighten a
few things to improve vividness.
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>
An adapter shutdown implicitly closes all open ports. Make sure to
mark all WKA ports as offline, not only the directory server. Also
make sure that no pending wka port work is running when the adapter is
being removed.
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>
When the FCP channel returns a series of commands with the error
status "test link", zfcp will send a series of ELS ADISC commands.
This is technically no problem, but it is enough to only issue one
test command per remote port. So, track whether a ELS ADISC command is
already pending, and do not send a new one if there is already a
pending command.
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>
Using a bitwise OR to not set anything at all is pointless so remove
the useless statement.
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 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>
In certain error scenarios ports, rports are getting attached,
validated and removed from the systems environment. Depending on the
layer this occurs asynchronously. This patch fixes the few races
which existed and ensures all references and cross references are
cleared at the time they're invalid. In addition fc transports
actions are only scheduled when required.
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 trace record for SCSI abort requests has a field for the request
id of the request to be aborted. Put the real request id instead of
zero.
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@HansenPartnership.com>
Under certain conditions it is possible that a WKA port ist not opened
within the expected timeframe of half a second. In this situation
the WKA port remains in the state OPENING preventing any succeding
request to open the port. This led to unrecoverable remote ports.
Fixing this by always setting an appropriate WKA port status before
leaving the function and removing the timeout value here since it's
not needed here because the general timeout processing would deal
with it if required.
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>
In a LOWMEM condition an ERP notification would have been sent twice
causing an unpredictable behaviour of the ERP.
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>
When calling fc_remote_port_add make sure to not call it again before
fc_remote_port_delete has been called. In other words, ensure to
create a new fc_rport, then delete it, then create a new one again.
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@HansenPartnership.com>
Depending on interruptions on some storage systems, the complete
channel can stall which looks like an outbound queue stall to Linux.
When trying to acquire a free SBAL for a non-SCSI command, zfcp waits
for 5 seconds for a free slot to appear. This is the right place to
detect a queue stall: If the wait times out, we assume a stalled queue
and try to recover this.
The overall strategy should be to trigger the erp from specific
events, and not try an overall escalation from one failed port to a
full-blown queue recovery. If we manage to send a command, the status
codes for this command or a timeout will trigger the right follow-on
actions.
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@HansenPartnership.com>
If an action fails, retry it until the erp count exceeds the
threshold. If there is something fundamentally wrong, the FSF layer
will trigger a more appropriate action depending on the FSF status
codes.
The followup for successful actions is a different followup than
retrying failed actions, so split the code two functions to make this
clear.
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@HansenPartnership.com>
After closing the port, we want it to be "not open" to consider the
action to be successful.
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@HansenPartnership.com>
The ELS ADISC and the GID_PN requests sent from zfcp fit into
unchained FSF requests. Change the FSF allocation logic to use
unchained requests whenever possible where everything fits in one
SBAL. This avoids acquiring more SBALs than necessary, especially
during zfcp recovery when things might be stalled.
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@HansenPartnership.com>
