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path: root/drivers/s390/scsi
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2009-10-22[SCSI] zfcp: Flush SCSI registration work when adding unitChristof Schmitt
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>
2009-10-22[SCSI] zfcp: Fix timer initialization for ct and els requestsChristof Schmitt
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>
2009-10-22[SCSI] zfcp: Warn about storage devices with broken PLOGI dataChristof Schmitt
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>
2009-10-22[SCSI] zfcp: Handle WWPN mismatch in PLOGI payloadChristof Schmitt
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>
2009-10-22[SCSI] zfcp: fix kfree handling in zfcp_init_device_setupHeiko Carstens
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>
2009-10-02[SCSI] zfcp: Fix hang when offlining device with offline chpidChristof Schmitt
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>
2009-10-02[SCSI] zfcp: Fix lockdep warning when offlining device with offline chpidChristof Schmitt
======================================================= [ 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>
2009-10-02[SCSI] zfcp: Fix oops during shutdown of offline deviceChristof Schmitt
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>
2009-10-02[SCSI] zfcp: Fix initial device and cfdc for delayed adapter allocationChristof Schmitt
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>
2009-10-02[SCSI] zfcp: correctly initialize unchained requestsChristof Schmitt
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>
2009-09-21trivial: remove unnecessary semicolonsJoe Perches
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-05[SCSI] zfcp: optimize zfcp_qdio_accountHeiko Carstens
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>
2009-09-05[SCSI] zfcp: Remove duplicated code for debug timestampsChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Handle failures during device allocation correctlyChristof Schmitt
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>
2009-09-05[SCSI] zfcp: proper use of device registerSebastian Ott
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>
2009-09-05[SCSI] zfcp: Replace config semaphore with mutexChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Defer resource allocation to first ccw_set_online callChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Simplify and update ct/gs and els timeout handlingChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Use kthread API for zfcp erp threadChristof Schmitt
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>
2009-09-05[SCSI] zfcp: resolve false usage of dd_data in fc_rportSwen Schillig
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>
2009-09-05[SCSI] zfcp: Apply common naming conventions to zfcp_fcSwen Schillig
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>
2009-09-05[SCSI] zfcp: introduce _setup, _destroy for qdio and FCSwen Schillig
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>
2009-09-05[SCSI] zfcp: Update dbf callsSwen Schillig
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>
2009-09-05[SCSI] zfcp: Decouple gid_pn requests from erpChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Move qdio related data out of zfcp_adapterSwen Schillig
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>
2009-09-05[SCSI] zfcp: Separate qdio attributes from zfcp_fsf_reqSwen Schillig
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>
2009-09-05[SCSI] zfcp: Move workqueue to adapter structSwen Schillig
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>
2009-09-05[SCSI] zfcp: Remove the useless ZFCP_REQ_AUTO_CLEANUP flagSwen Schillig
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>
2009-09-05[SCSI] zfcp: Improve request allocation through mempoolsSwen Schillig
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>
2009-09-05[SCSI] zfcp: Replace fsf_req wait_queue with completionSwen Schillig
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>
2009-09-05[SCSI] zfcp: fix layering oddities between zfcp_fsf and zfcp_qdioSwen Schillig
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>
2009-09-05[SCSI] zfcp: Implicitly close all wka portsChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Only issue one test link command per portChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Remove useless assignmentChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Only collect FSF/HBA debug data for matching trace levelsChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Only collect SCSI debug data for matching trace levelsChristof Schmitt
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>
2009-09-05[SCSI] zfcp: Move debug data from zfcp_data to own data structureChristof Schmitt
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>
2009-09-05[SCSI] zfcp: invalid usage after free of port resourcesSwen Schillig
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>
2009-07-30[SCSI] zfcp: Fix tracing of request id for abort requestsChristof Schmitt
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>
2009-07-30[SCSI] zfcp: Fix wka port processingSwen Schillig
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>
2009-07-30[SCSI] zfcp: avoid double notify in lowmem scenarioSwen Schillig
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>
2009-07-30[SCSI] zfcp: Add port only once to FC transport classChristof Schmitt
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>
2009-07-30[SCSI] zfcp: Recover from stalled outbound queueChristof Schmitt
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>
2009-07-30[SCSI] zfcp: Fix erp escalation procedureChristof Schmitt
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>
2009-07-30[SCSI] zfcp: Fix logic for physical port closeChristof Schmitt
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>
2009-07-30[SCSI] zfcp: Use -EIO for SBAL allocation failuresChristof Schmitt
-ENOMEM is for memory allocation problems, -EIO for queue/SBAL allocation problems. 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>
2009-07-30[SCSI] zfcp: Use unchained mode for small ct and els requestsChristof Schmitt
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>
2009-07-30[SCSI] zfcp: Use correct flags for zfcp_erp_notifyChristof Schmitt
zfcp_erp_notify uses the ZFCP_ERP_STATUS_* flags, so it is ZFCP_STATUS_ERP_LOWMEM instead of ZFCP_ERP_NOMEM. Signalling ZFCP_ERP_FAILED is not necessary, the missing d_id will show that the nameserver did not return the d_id. 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>
2009-07-30[SCSI] zfcp: Return -ENOMEM for allocation failures in zfcp_fsfChristof Schmitt
When a fsf_req or a qtcb cannot be allocated return -ENOMEM instead of -EIO. 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>
2009-07-30[SCSI] zfcp: Acquire qdio_stat_lock when reading the queue utilizationChristof Schmitt
req_q_util is not atomic, so the qdio_stat_lock must be held when reading this variable. 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>