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path: root/drivers/scsi/hpsa.h
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2015-02-02hpsa: Use local workqueues instead of system workqueuesDon Brace
Suggested-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Webb Scales <webbnh@hp.com> Reviewed-by: Kevin Barnett <Kevin.Barnett@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: do not use function pointers in fast path command submissionStephen Cameron
Performance tweak, avoid unnecessary function calls. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: do not check for msi(x) in interrupt_pendingStephen Cameron
No need to check whether interrupt pending for MSI(X) and conversely, no need to check whether MSI(X) interrupts are being used when checking if interrupts are pending. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: slightly optimize SA5_performant_completedDon Brace
Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: count passthru cmds with atomics, not a spin locked intDon Brace
Performance enhancement. Remove spin_locks from the driver. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: optimize cmd_alloc function by remembering last allocationRobert Elliott
Empirically, this improves performance slightly (~2% max IOPS) by allowing cmd_alloc to remember where it left off searching for free commands between calls instead of always starting its search at command 0. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Robert Elliott <elliott@hp.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: fix race between abort handler and main i/o pathWebb Scales
This means changing the allocator to reference count commands. The reference count is now the authoritative indicator of whether a command is allocated or not. The h->cmd_pool_bits bitmap is now only a heuristic hint to speed up the allocation process, it is no longer the authoritative record of allocated commands. Since we changed the command allocator to use reference counting as the authoritative indicator of whether a command is allocated, fail_all_outstanding_cmds needs to use the reference count not h->cmd_pool_bits for this purpose. Fix hpsa_drain_accel_commands to use the reference count as the authoritative indicator of whether a command is allocated instead of the h->cmd_pool_bits bitmap. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: honor queue depth of physical devicesDon Brace
When using the ioaccel submission methods, requests destined for RAID volumes are sometimes diverted to physical devices. The OS has no or limited knowledge of these physical devices, so it is up to the driver to avoid pushing the device too hard. It is better to honor the physical device queue limit rather than making the device spew zillions of TASK SET FULL responses. This is so that hpsa based devices support /sys/block/sdNN/device/queue_type of simple, which lets the SCSI midlayer automatically adjust the queue_depth based on TASK SET FULL and GOOD status. Adjust the queue depth for a new device after it is created based on the maximum queue depths of the physical devices that constitute the device. This drops the maximum queue depth from .can_queue of 1024 to something like 174 for single-drive RAID-0, 348 for two-drive RAID-1, etc. It also adjusts for the ratio of data to parity drives. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Webb Scales <webbnh@hp.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: use workqueue to resubmit failed ioaccel commandsDon Brace
Instead of kicking the commands all the way back to the mid layer, use a work queue. This enables having a mechanism for the driver to be able to resubmit the commands down the "normal" raid path without turning off the ioaccel feature entirely whenever an error is encountered on the ioaccel path, and prevent excessive rescanning of devices. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: do not request device rescan on every ioaccel path errorStephen Cameron
The original reasoning behind doing this was faulty. An error of some sort would be encountered, accelerated i/o would be disabled for that logical drive, the command would be kicked back out to the SCSI midlayer for a retry, and since i/o accelerator mode was disabled, it would get retried down the RAID path. However, something needs to turn ioaccellerator mode back on, and this rescan request was what did that. However, it was racy, and extremely bad for performance to rescan all devices, so, don't do that. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: do not queue commands internally in driverDon Brace
By not doing maintaining a list of queued commands, we can eliminate some spin locking in the main i/o path and gain significant improvement in IOPS. Remove the queuing code and the code that calls it; remove now-unused interrupt code; remove DIRECT_LOOKUP_BIT. Now that the passthru commands share the same command pool as the main i/o path, and the total size of the pool is less than or equal to the number of commands that will fit in the hardware fifo, there is no need to check to see if we are exceeding the hardware fifo's depth. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Reviewed-by: Robert Elliott <elliott@hp.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: get rid of cmd_special_alloc and cmd_special_freeStephen Cameron
We have commands reserved for internal use. This is laying the groundwork for removing the internal queue of commands from the driver so that the locks that protect that queue may be removed. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02hpsa: reserve some commands for use by driverStephen Cameron
We need to reserve some commands for device rescans, aborts, and the pass through ioctls, etc. so we cannot give them all to the scsi mid layer. This is in preparation for removing cmd_special_alloc and cmd_special_free so that we can stop queuing commands internally in the driver so that we can remove the locks thta protect the queue that we will no longer have. Reviewed-by: Scott Teel <scott.teel@pmcs.com> Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20hpsa: use atomics for commands_outstandingStephen M. Cameron
Use atomics for commands_outstanding instead of protecting with spin locks. Signed-off-by: Don Brace <don.brace@pmcs.com> Signed-off-by: Stephen M. Cameron <stephenmcameron@gmail.com> Reviewed-by: Joe Handzik <joseph.t.handzik@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20hpsa: Clean up warnings from sparse.Don Brace
Clean up issues reported when running sparse. Signed-off-by: Don Brace <don.brace@pmcs.com> Reviewed-by: Webb Scales <webb.scales@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-02hpsa: fix event filtering to prevent excessive rescans with old firmwareStephen M. Cameron
CTLR_STATE_CHANGE_EVENT and CTLR_STATE_CHANGE_EVENT_REDUNDANT_CNTRL do not require rescans to be initiated. Current firmware filters out these events already, but some out of date firmware doesn't, so the driver needs to filter them out too. Without this change and with out of date firmware you may see the driver spending a lot of time scanning devices unnecessarily on some Smart Arrays. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Reviewed-by: Justin Lindley <justin.lindley@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-02hpsa: avoid unnecessary readl on every command submissionStephen M. Cameron
for controllers which support either of the ioaccel transport methods. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Reviewed-by: Mike Miller <michael.miller@canonical.com> Reviewed-by: Joe Handzik <joseph.t.handzik@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-02hpsa: use per-cpu variable for lockup_detectedStephen M. Cameron
Avoid excessive locking by using per-cpu variable for lockup_detected Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Reviewed-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-02hpsa: allocate reply queues individuallyStephen M. Cameron
Now that we can allocate more than 4 reply queues (up to 64) we shouldn't try to make them share the same allocation but should allocate them separately. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Reviewed-by: Mike Miller <michael.miller@canonical.com> Reviewed-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-02hpsa: remove dev_dbg() calls from hot pathsStephen M. Cameron
They are not completely free of cost when disabled and when enabled emitting debug output for every command submitted produces far too much output to be useful. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Reviewed-by: Mike Miller <michael.miller@canonical.com> Reviewed-by: Webb Scales <webb.scales@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-06-02hpsa: remove unused fields from struct ctlr_infoStephen M. Cameron
The fields "major", "max_outstanding", and "usage_count" of struct ctlr_info were not used for anything. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Reviewed-by: Mike Miller <michael.miller@canonical.com> Reviewed-by: Webb Scales <webb.scales@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-05-19hpsa: fix memory leak in hpsa_hba_mode_enabledJoe Handzik
And while we're at it fix a magic number Signed-off-by: Joe Handzik <joseph.t.handzik@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-03-15[SCSI] hpsa: Add hba mode to the hpsa driverStephen M. Cameron
This allows exposing physical disks behind Smart Array controllers to the OS (if the controller has the right firmware and is in "hba" mode) Signed-off-by: Joe Handzik <joseph.t.handzik@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: bring format-in-progress drives online when readyStephen M. Cameron
Do not expose drives that are undergoing a format immediately to the OS, instead wait until they are ready before bringing them online. This is so that logical drives created with "rapid parity initialization" do not get immediately kicked off the system for being unresponsive. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa add sysfs debug switch for raid map debugging messagesStephen M. Cameron
Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: only do device rescan for certain eventsStephen M. Cameron
Do no rescan on every events -- way too many rescans are triggered if we don't filter the events. Limit rescans to be triggered by the following set of events: * controller state change * enclosure hot plug * physical drive state change * logical drive state change * redundant controller state change * accelerated io enabled/disabled * accelerated io configuration change Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: update source file copyrightsScott Teel
Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: rescan devices on ioaccel2 errorScott Teel
Allow driver to schedule a rescan whenever a request fails on the ioaccel2 path. This eliminates the possibility of driver getting stuck in non-ioaccel mode. IOaccel mode (HP SSD Smart Path) is disabled by driver upon error detection. Driver relied on idea that request would be retried through normal path, and a subsequent error would occur on that path, and be processed by controller firmware. As part of that process, controller disables ioaccel mode and later reinstates it, signalling driver to change modes. In some error cases, the error will not duplicate on the standard path, so the driver could get stuck in non-ioaccel mode. To avoid that, we allow driver to request a rescan during the next run of the rescan thread. Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: allow user to disable accelerated i/o pathScott Teel
Allow SSD Smart Path for a controller to be disabled by the user, regardless of settings in controller firmware or array configuration. To disable: echo 0 > /sys/class/scsi_host/host<id>/acciopath_status To re-enable: echo 1 > /sys/class/scsi_host/host<id>/acciopath_status To check state: cat /sys/class/scsi_host/host<id>/acciopath_status Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: get ioaccel mode 2 i/o workingScott Teel
Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Joe Handzik <Joseph.T.Handzik@hp.com> Signed-off-by: Mike Miller <michael.miller@canonical.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: initialize controller to perform io accelerator mode 2Stephen M. Cameron
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: do ioaccel mode 2 resource allocationsStephen M. Cameron
Signed-off-by: Mike Miller <michael.miller@canonical.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: add ioaccel mode 2 structure definitionsMike Miller
Signed-off-by: Mike Miller <michael.miller@canonical.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: poll controller to detect device change eventStephen M. Cameron
For shared SAS configurations, hosts need to poll Smart Arrays periodically in order to be able to detect configuration changes such as logical drives being added or removed from remote hosts. A register on the controller indicates when such events have occurred, and the driver polls the register via a workqueue and kicks off a rescan of devices if such an event is detected. Additionally, changes to logical drive raid offload eligibility are autodetected in this way. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: add ioaccell mode 1 RAID offload support.Stephen M. Cameron
This enables sending i/o's destined for RAID logical drives which can be serviced by a single physical disk down a different, faster i/o path directly to physical drives for certain logical volumes on SSDs bypassing the Smart Array RAID stack for a performance improvement. Signed-off-by: Matt Gates <matthew.gates@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Mike Miller <michael.miller@canonical.com> Signed-off-by: Don Brace <brace@beardog.cce.hp.com> Signed-off-by: Joe Handzik <joseph.t.handzik@hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2014-03-15[SCSI] hpsa: add support for 'fastpath' i/oMatt Gates
For certain i/o's to certain devices (unmasked physical disks) we can bypass the RAID stack firmware and do the i/o to the device directly and it will be faster. Signed-off-by: Matt Gates <matthew.gates@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-12-19[SCSI] hpsa: use workqueue instead of kernel thread for lockup detectionStephen M. Cameron
Much simpler and avoids races starting/stopping the thread. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-12-19[SCSI] hpsa: prevent stalled i/oStephen M. Cameron
If a fifo full condition is encountered, i/o requests will stack up in the h->reqQ queue. The only thing which empties this queue is start_io, which only gets called when new i/o requests come in. If none are forthcoming, i/o in h->reqQ will be stalled. To fix this, whenever fifo full condition is encountered, this is recorded, and the interrupt handler examines this to see if a fifo full condition was recently encountered when a command completes and will call start_io to prevent i/o's in h->reqQ from getting stuck. I've only ever seen this problem occur when running specialized test programs that pound on the the CCISS_PASSTHRU ioctl. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-12-19[SCSI] hpsa: cap CCISS_PASSTHRU at 20 concurrent commands.Stephen M. Cameron
Cap CCISS_BIG_PASSTHRU as well. If an attempt is made to exceed this, ioctl() will return -1 with errno == EAGAIN. This is to prevent a userland program from exhausting all of pci_alloc_consistent memory. I've only seen this problem when running a special test program designed to provoke it. 20 concurrent commands via the passthru ioctls (not counting SG_IO) should be more than enough. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-08-26[SCSI] hpsa: remove unneeded variableTomas Henzl
Signed-off-by: Tomas Henzl <thenzl@redhat.com> Acked-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-10[SCSI] hpsa: dial down lockup detection during firmware flashStephen M. Cameron
Dial back the aggressiveness of the controller lockup detection thread. Currently it will declare the controller to be locked up if it goes for 10 seconds with no interrupts and no change in the heartbeat register. Dial back this to 30 seconds with no heartbeat change, and also snoop the ioctl path and if a firmware flash command is detected, dial it back further to 4 minutes until the firmware flash command completes. The reason for this is that during the firmware flash operation, the controller apparently doesn't update the heartbeat register as frequently as it is supposed to, and we can get a false positive. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-10[SCSI] hpsa: removed unused member maxQsinceinitStephen M. Cameron
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-10[SCSI] hpsa: refine interrupt handler locking for greater concurrencyMatt Gates
Use spinlocks with finer granularity in the submission and completion paths to allow concurrent execution for multiple reply queues. In particular, do not hold a spin lock while submitting a request to the device, nor during most of the interrupt handler. Signed-off-by: Matt Gates <matthew.gates@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-10[SCSI] hpsa: use multiple reply queuesMatt Gates
Smart Arrays can support multiple reply queues onto which command completions may be deposited. It can help performance quite a bit to arrange for command completions to be processed on the same CPU from which they were submitted to increase the likelihood of cache hits. Signed-off-by: Matt Gates <matthew.gates@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-10[SCSI] hpsa: add abort error handler functionStephen M. Cameron
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-05-10[SCSI] hpsa: do not read from controller unnecessarily in completion codeStephen M. Cameron
MSI/MSI-X interrupts can't race the DMA completion they are communicating so no need to read from controller to flush the DMA to the host if MSI or MSI-X interrupts are being used. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] hpsa: factor out driver nameStephen M. Cameron
Sometimes, for testing purposes (e.g. testing rmmod on a system that normally boots using hpsa) it's nice to rename the driver and split it into two drivers and restrict it to certain controllers. This makes that easier. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] hpsa: removed unneeded structure member max_sg_entries and fix badly ↵Stephen M. Cameron
named constant MAXSGENTRIES We had both h->max_sg_entries and h->maxsgentries in the per controller structure which is terribly confusing. max_sg_entries was really just a constant, 32, which defines how big the "block fetch table" is, which is as large as the max number of SG elements embedded within a command (excluding SG elements in chain blocks). MAXSGENTRIES was the constant used to denote the max number of SG elements embedded within a command, also a poor name. So renamed MAXSGENTREIS to SG_ENTRIES_IN_CMD, and removed h->max_sg_entries and replaced it with SG_ENTRIES_IN_CMD. h->maxsgentries is unchanged, and is the maximum number of sg elements the controller will support in a command, including those in chain blocks, minus 1 for the chain block pointer.. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-30[SCSI] hpsa: detect controller lockupStephen M. Cameron
When controller lockup condition is detected, we should fail all outstanding commands and disable the controller. This will enable multipath solutions to recover gracefully. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-30[SCSI] hpsa: fix potential array overflow in hpsa_update_scsi_devicesScott Teel
The currentsd[] array in hpsa_update_scsi_devices had room for 256 devices. The code was iterating over however many physical and logical devices plus an additional number of possible external MSA2XXX controllers, which together could potentially exceed 256. We increased the size of the currentsd array to 1024 + 1024 + 32 + 1 elements to reflect a reasonable maximum possible number of devices which might be encountered. We also don't just walk off the end of the array if the array controller reports more devices than we are prepared to handle, we just ignore the excessive devices. Signed-off-by: Scott Teel <scott.teel@hp.com> Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>