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2017-09-15scsi: libsas: remove the numbering for each event enumJason Yan
Numbering for each event enum makes no sense. Remove the numbering so that we don't have to calculate the number by hand every time. Signed-off-by: Jason Yan <yanaijie@huawei.com> CC: John Garry <john.garry@huawei.com> CC: Johannes Thumshirn <jthumshirn@suse.de> CC: Ewan Milne <emilne@redhat.com> CC: Christoph Hellwig <hch@lst.de> CC: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-09-15scsi: libsas: kill useless ha_event and do some cleanupJason Yan
The ha_event now has only one event HAE_RESET, and this event does nothing. Kill it and do some cleanup. This is a preparation for enhance libsas hotplug feature in the next patches. Signed-off-by: Jason Yan <yanaijie@huawei.com> Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> CC: Johannes Thumshirn <jthumshirn@suse.de> CC: Ewan Milne <emilne@redhat.com> CC: Christoph Hellwig <hch@lst.de> CC: Tomas Henzl <thenzl@redhat.com> CC: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-29scsi: scsi_transport_sas: switch to bsg-lib for SMP passthroughChristoph Hellwig
Simplify the SMP passthrough code by switching it to the generic bsg-lib helpers that abstract away the details of the request code, and gets drivers out of seeing struct scsi_request. For the libsas host SMP code there is a small behavior difference in that we now always clear the residual len for successful commands, similar to the three other SMP handler implementations. Given that there is no partial command handling in the host SMP handler this should not matter in practice. [mkp: typos and checkpatch fixes] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-25scsi: libsas: move bus_reset_handler() to target_reset_handler()Hannes Reinecke
The bus reset handler is calling I_T Nexus reset, which logically is a target reset as it need to specify both the initiator and the target. So move it to target reset. Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-27scsi: sas: scsi_queue_work can fail, so make callers awareJohannes Thumshirn
libsas uses scsi_queue_work() to queue its internal event notifications. scsi_queue_work() can return -EINVAL if the work queue doesn't exist and it does call queue_work() which can return false if the work is already queued. Make the SAS event code capable of returning errors up to the caller, which is handy when changing to dynamically allocated work in libsas as well, as discussed here: https://lkml.org/lkml/2017/6/14/121. [mkp: fixed typo] Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-04scsi: sas: remove sas_domain_release_transportJohannes Thumshirn
sas_domain_release_transport is unused since at least v3.13, remove it. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2014-12-18Merge remote-tracking branch 'scsi-queue/drivers-for-3.19' into for-linusJames Bottomley
2014-12-11Merge branch 'for-3.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata Pull libata changes from Tejun Heo: "The only interesting piece is the support for shingled drives. The changes in libata layer are minimal. All it does is identifying the new class of device and report upwards accordingly" * 'for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: libata: Remove FIXME comment in atapi_request_sense() sata_rcar: Document deprecated "renesas,rcar-sata" sata_rcar: Add clocks to sata_rcar bindings ahci_sunxi: Make AHCI_HFLAG_NO_PMP flag configurable with a module option libata-scsi: Update SATL for ZAC drives libata: Implement ATA_DEV_ZAC libsas: use ata_dev_classify()
2014-12-04scsi: remove ->change_queue_type methodChristoph Hellwig
Since we got rid of ordered tag support in 2010 the prime use case of switching on and off ordered tags has been obsolete. The other function of enabling/disabling tagging entirely has only been correctly implemented by the 53c700 driver and isn't generally useful. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-27libsas: remove task_collector modeChristoph Hellwig
The task_collector mode (or "latency_injector", (C) Dan Willians) is an optional I/O path in libsas that queues up scsi commands instead of directly sending it to the hardware. It generall increases latencies to in the optiomal case slightly reduce mmio traffic to the hardware. Only the obsolete aic94xx driver and the mvsas driver allowed to use it without recompiling the kernel, and most drivers didn't support it at all. Remove the giant blob of code to allow better optimizations for scsi-mq in the future. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Dan Williams <dan.j.williams@intel.com>
2014-11-24scsi: drop reason argument from ->change_queue_depthChristoph Hellwig
Drop the now unused reason argument from the ->change_queue_depth method. Also add a return value to scsi_adjust_queue_depth, and rename it to scsi_change_queue_depth now that it can be used as the default ->change_queue_depth implementation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-05libsas: use ata_dev_classify()Hannes Reinecke
Use the ata device class from libata in libsas instead of checking the supported command set and switch to using ata_dev_classify() instead of our own method. Cc: Tejun Heo <tj@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-03-18libata, libsas: kill pm_result and related cleanupDan Williams
Tejun says: "At least for libata, worrying about suspend/resume failures don't make whole lot of sense. If suspend failed, just proceed with suspend. If the device can't be woken up afterwards, that's that. There isn't anything we could have done differently anyway. The same for resume, if spinup fails, the device is dud and the following commands will invoke EH actions and will eventually fail. Again, there really isn't any *choice* to make. Just making sure the errors are handled gracefully (ie. don't crash) and the following commands are handled correctly should be enough." The only libata user that actually cares about the result from a suspend operation is libsas. However, it only cares about whether queuing a new operation collides with an in-flight one. All libsas does with the error is retry, but we can just let libata wait for the previous operation before continuing. Other cleanups include: 1/ Unifying all ata port pm operations on an ata_port_pm_ prefix 2/ Marking all ata port pm helper routines as returning void, only ata_port_pm_ entry points need to fake a 0 return value. 3/ Killing ata_port_{suspend|resume}_common() in favor of calling ata_port_request_pm() directly 4/ Killing the wrappers that just do a to_ata_port() conversion 5/ Clearly marking the entry points that do async operations with an _async suffix. Reference: http://marc.info/?l=linux-scsi&m=138995409532286&w=2 Cc: Phillip Susi <psusi@ubuntu.com> Cc: Alan Stern <stern@rowland.harvard.edu> Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Todd Brandt <todd.e.brandt@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-04[SCSI] libsas: implement > 16 byte CDB supportJames Bottomley
Remove the arbitrary expectation in libsas that all SCSI commands are 16 bytes or less. Instead do all copies via cmd->cmd_len (and use a pointer to this in the libsas task instead of a copy). Note that this still doesn't enable > 16 byte CDB support in the underlying drivers because their internal format has to be fixed and the wire format of > 16 byte CDBs according to the SAS spec is different. the libsas drivers (isci, aic94xx, mvsas and pm8xxx are all updated for this change. Cc: Lukasz Dorau <lukasz.dorau@intel.com> Cc: Maciej Patelczyk <maciej.patelczyk@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Jack Wang <xjtuwjp@gmail.com> Cc: Lindar Liu <lindar_liu@usish.com> Cc: Xiangliang Yu <yuxiangl@marvell.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-05-10[SCSI] sas: unify the pointlessly separated enums sas_dev_type and ↵James Bottomley
sas_device_type These enums have been separate since the dawn of SAS, mainly because the latter is a procotol only enum and the former includes additional state for libsas. The dichotomy causes endless confusion about which one you should use where and leads to pointless warnings like this: drivers/scsi/mvsas/mv_sas.c: In function 'mvs_update_phyinfo': drivers/scsi/mvsas/mv_sas.c:1162:34: warning: comparison between 'enum sas_device_type' and 'enum sas_dev_type' [-Wenum-compare] Fix by eliminating one of them. The one kept is effectively the sas.h one, but call it sas_device_type and make sure the enums are all properly namespaced with the SAS_ prefix. Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-08-24[SCSI] libsas: suspend / resume supportDan Williams
libsas power management routines to suspend and recover the sas domain based on a model where the lldd is allowed and expected to be "forgetful". sas_suspend_ha - disable event processing allowing the lldd to take down links without concern for causing hotplug events. Regardless of whether the lldd actually posts link down messages libsas notifies the lldd that all domain_devices are gone. sas_prep_resume_ha - on the way back up before the lldd starts link training clean out any spurious events that were generated on the way down, and re-enable event processing sas_resume_ha - after the lldd has started and decided that all phys have posted link-up events this routine is called to let libsas start it's own timeout of any phys that did not resume. After the timeout an lldd can cancel the phy teardown by posting a link-up event. Storage for ex_change_count (u16) and phy_change_count (u8) are changed to int so they can be set to -1 to indicate 'invalidated'. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jacek Danecki <jacek.danecki@intel.com> Tested-by: Maciej Patelczyk <maciej.patelczyk@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] libsas: trim sas_task of slow path infrastructureDan Williams
The timer and the completion are only used for slow path tasks (smp, and lldd tmfs), yet we incur the allocation space and cpu setup time for every fast path task. Cc: Xiangliang Yu <yuxiangl@marvell.com> Acked-by: Jack Wang <jack_wang@usish.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] libsas: drop sata port multiplier infrastructureDan Williams
On the way to add a new sata_device field, noticed that libsas is carrying port multiplier infrastructure that is explicitly disabled by sas_discover_sata(). The aic94xx touches the unused port_no, so leave that field in case there was some use for it. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] libsas: add sas_eh_abort_handlerDan Williams
When recovering failed eh-cmnds let the lldd attempt an abort via scsi_abort_eh_cmnd before escalating. Reviewed-by: Jacek Danecki <jacek.danecki@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] libsas: enforce eh strategy handlers only in eh contextDan Williams
The strategy handlers may be called in places that are problematic for libsas (i.e. sata resets outside of domain revalidation filtering / libata link recovery), or problematic for userspace (non-blocking ioctl to sleeping reset functions). However, these routines are also called for eh escalations and recovery of scsi_eh_prep_cmnd(), so permit them as long as we are running in the host's error handler, otherwise arrange for them to be triggered in eh_context. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] libata, libsas: introduce sched_eh and end_eh port opsDan Williams
When managing shost->host_eh_scheduled libata assumes that there is a 1:1 shost-to-ata_port relationship. libsas creates a 1:N relationship so it needs to manage host_eh_scheduled cumulatively at the host level. The sched_eh and end_eh port port ops allow libsas to track when domain devices enter/leave the "eh-pending" state under ha->lock (previously named ha->state_lock, but it is no longer just a lock for ha->state changes). Since host_eh_scheduled indicates eh without backing commands pinning the device it can be deallocated at any time. Move the taking of the domain_device reference under the port_lock to guarantee that the ata_port stays around for the duration of eh. Reviewed-by: Jacek Danecki <jacek.danecki@intel.com> Acked-by: Jeff Garzik <jgarzik@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-08[SCSI] libsas: fix taskfile corruption in sas_ata_qc_fill_rtfDan Williams
fill_result_tf() grabs the taskfile flags from the originating qc which sas_ata_qc_fill_rtf() promptly overwrites. The presence of an ata_taskfile in the sata_device makes it tempting to just copy the full contents in sas_ata_qc_fill_rtf(). However, libata really only wants the fis contents and expects the other portions of the taskfile to not be touched by ->qc_fill_rtf. To that end store a fis buffer in the sata_device and use ata_tf_from_fis() like every other ->qc_fill_rtf() implementation. Cc: <stable@vger.kernel.org> Reported-by: Praveen Murali <pmurali@logicube.com> Tested-by: Praveen Murali <pmurali@logicube.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23[SCSI] libsas: introduce sas_work to fix sas_drain_work vs sas_queue_workDan Williams
When requeuing work to a draining workqueue the last work instance may not be idle, so sas_queue_work() must not touch work->entry. Introduce sas_work with a drain_node list_head to have a private list for collecting work deferred due to drain collision. Fixes reports like: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff810410d4>] process_one_work+0x2e/0x338 Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29[SCSI] libsas: revert ata srstDan Williams
libata issues follow up srsts when the controller has a hard time recording the signature-fis after a reset, or if the link supports port multipliers. libsas does not support port multipliers and no current libsas lldds appear to need help retrieving the signature fis. Revert it for now to remove confusion. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29[SCSI] libsas: async ata scanningDan Williams
libsas ata error handling is already async but this does not help the scan case. Move initial link recovery out from under host->scan_mutex, and delay synchronization with eh until after all port probe/recovery work has been queued. Device ordering is maintained with scan order by still calling sas_rphy_add() in order of domain discovery. Since we now scan the domain list when invoking libata-eh we need to be careful to check for fully initialized ata ports. Acked-by: Jack Wang <jack_wang@usish.com> Acked-by: Jeff Garzik <jgarzik@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29[SCSI] libsas: mark all domain devices gone if root port disappearsDan Williams
If the top level expander is hot removed, mark all child devices as gone before unregistration to short circuit futile recovery. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29[SCSI] libsas: fix sas_find_local_phy(), take phy referencesDan Williams
In the direct-attached case this routine returns the phy on which this device was first discovered. Which is broken if we want to support wide-targets, as this phy reference can become stale even though the port is still active. In the expander-attached case this routine tries to lookup the phy by scanning the attached sas addresses of the parent expander, and BUG_ONs if it can't find it. However since eh and the libsas workqueue run independently we can still be attempting device recovery via eh after libsas has recorded the device as detached. This is even easier to hit now that eh is blocked while device domain rediscovery takes place, and that libata is fed more timed out commands increasing the chances that it will try to recover the ata device. Arrange for dev->phy to always point to a last known good phy, it may be stale after the port is torn down, but it will catch up for wide port reconfigurations, and never be NULL. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29[SCSI] libsas: poll for ata device readiness after resetDan Williams
Use ata_wait_after_reset() to poll for link recovery after a reset. This combined with sas_ha->eh_mutex prevents expander rediscovery from probing phys in an intermediate state. Local discovery does not have a mechanism to filter link status changes during this timeout, so it remains the responsibility of lldds to prevent premature port teardown. Although once all lldd's support ->lldd_ata_check_ready() that could be used as a gate to local port teardown. The signature fis is re-transmitted when the link comes back so we should be revalidating the ata device class, but that is left to a future patch. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: add mutex for SMP task executionJeff Skirvin
SAS does not tag SMP requests, and at least one lldd (isci) does not permit more than one in-flight request at a time. [jejb: fix sas_init_dev tab issues while we're at it] Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: sas_phy_enable via transport_sas_phy_resetDan Williams
Execute the link-reset triggered by sas_phy_enable via transport_sas_phy_reset so that it can be managed by libata. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: let libata handle command timeoutsDan Williams
libsas-eh if it successfully aborts an ata command will hide the timeout condition (AC_ERR_TIMEOUT) from libata. The command likely completes with the all-zero task->task_status it started with. Instead, interpret a TMF_RESP_FUNC_COMPLETE as the end of the sas_task but keep the scmd around for libata-eh to handle. Tested-by: Andrzej Jakowski <andrzej.jakowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: fix timeout vs completion raceDan Williams
Until we have told the lldd to forget a task a timed out operation can return from the hardware at any time. Since completion frees the task we need to make sure that no tasks run their normal completion handler once eh has decided to manage the task. Similar to ata_scsi_cmd_error_handler() freeze completions to let eh judge the outcome of the race. Task collector mode is problematic because it presents a situation where a task can be timed out and aborted before the lldd has even seen it. For this case we need to guarantee that a task that an lldd has been told to forget does not get queued after the lldd says "never seen it". With sas_scsi_timed_out we achieve this with the ->task_queue_flush mutex, rather than adding more time. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: prevent double completion of scmds from ehDan Williams
We invoke task->task_done() to free the task in the eh case, but at this point we are prepared for scsi_eh_flush_done_q() to finish off the scmd. Introduce sas_end_task() to capture the final response status from the lldd and free the task. Also take the opportunity to kill this warning. drivers/scsi/libsas/sas_scsi_host.c: In function ‘sas_end_task’: drivers/scsi/libsas/sas_scsi_host.c:102:3: warning: case value ‘2’ not in enumerated type ‘enum exec_status’ [-Wswitch] Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: close error handling vs sas_ata_task_done() raceDan Williams
Since sas_ata does not implement ->freeze(), completions for scmds and internal commands can still arrive concurrent with ata_scsi_cmd_error_handler() and sas_ata_post_internal() respectively. By the time either of those is called libata has committed to completing the qc, and the ATA_PFLAG_FROZEN flag tells sas_ata_task_done() it has lost the race. In the sas_ata_post_internal() case we take on the additional responsibility of freeing the sas_task to close the race with sas_ata_task_done() freeing the the task while sas_ata_post_internal() is in the process of invoking ->lldd_abort_task(). Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: use ->set_dmamode to notify lldds of NCQ parametersDan Williams
sas_discover_sata() notifies lldds of sata devices twice. Once to allow the 'identify' to be sent, and a second time to allow aic94xx (the only libsas driver that cares about sata_dev.identify) to setup NCQ parameters before the device becomes known to the midlayer. Replace this double notification and intervening 'identify' with an explicit ->lldd_ata_set_dmamode notification. With this change all ata internal commands are issued by libata, so we no longer need sas_issue_ata_cmd(). The data from the identify command only needs to be cached in one location so ata_device.id replaces domain_device.sata_dev.identify. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: prevent domain rediscovery competing with ata error handlingDan Williams
libata error handling provides for a timeout for link recovery. libsas must not rescan for previously known devices in this interval otherwise it may remove a device that is simply waiting for its link to recover. Let libata-eh make the determination of when the link is stable and prevent libsas (host workqueue) from taking action while this determination is pending. Using a mutex (ha->disco_mutex) to flush and disable revalidation while eh is running requires any discovery action that may block on eh be moved to its own context outside the lock. Probing ATA devices explicitly waits on ata-eh and the cache-flush-io issued during device removal may also pend awaiting eh completion. Essentially any rphy add/remove activity needs to run outside the lock. This adds two new cleanup states for sas_unregister_domain_devices() 'allocated-but-not-probed', and 'flagged-for-destruction'. In the 'allocated-but-not-probed' state dev->rphy points to a rphy that is known to have not been through a sas_rphy_add() event. At domain teardown check if this device is still pending probe and cleanup accordingly. Similarly if a device has already been queued for removal then sas_unregister_domain_devices has nothing to do. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: convert dev->gone to flagsDan Williams
In preparation for adding tracking of another device state "destroy". Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: introduce sas_drain_work()Dan Williams
When an lldd invokes ->notify_port_event() it can trigger a chain of libsas events to: 1/ form the port and find the direct attached device 2/ if the attached device is an expander perform domain discovery A call to flush_workqueue() will only flush the initial port formation work. Currently libsas users need to call scsi_flush_work() up to the max depth of chain (which will grow from 2 to 3 when ata discovery is moved to its own discovery event). Instead of open coding multiple calls switch to use drain_workqueue() to flush sas work. drain_workqueue() does not handle new work submitted during the drain so libsas needs a bit of infrastructure to hold off unchained work submissions while a drain is in flight. A lldd ->notify() event is considered 'unchained' while a sas_discover_event() is 'chained'. As Tejun notes: "For now, I think it would be best to add private wrapper in libsas to support deferring unchained work items while draining." Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: convert ha->state to flagsDan Williams
In preparation for adding new states (SAS_HA_DRAINING, SAS_HA_FROZEN), convert ha->state into a set of flags. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: replace event locks with atomic bitopsDan Williams
The locks only served to make sure the pending event bitmask was updated consistently. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: fix domain_device leakDan Williams
Arrange for the deallocation of a struct domain_device object when it no longer has: 1/ any children 2/ references by any scsi_targets 3/ references by a lldd The comment about domain_device lifetime in Documentation/scsi/libsas.txt is stale as it appears mainline never had a version of a struct domain_device that was registered as a kobject. We now manage domain_device reference counts on behalf of external agents. Reviewed-by: Jack Wang <jack_wang@usish.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: kill sas_slave_destroyDan Williams
Per commit 3e4ec344 "libata: kill ATA_FLAG_DISABLED" needing to set ATA_DEV_NONE is a holdover from before libsas converted to the "new-style" ata-eh. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19[SCSI] libsas: remove unused ata_task_resp fieldsDan Williams
Commit 1e34c838 "[SCSI] libsas: remove spurious sata control register read/write" removed the routines to fake the presence of the sata control registers, now remove the unused data structure fields to kill any remaining confusion. Acked-by: Jack Wang <jack_wang@usish.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-16[SCSI] libsas: fix port->dev_list lockingDan Williams
port->dev_list maintains a list of devices attached to a given sas root port. It needs to be mutated under a lock as contexts outside of the single-threaded-libsas-workqueue access the list via sas_find_dev_by_rphy(). Fixup locations where the list was being mutated without a lock. This is a follow-up to commit 5911e963 "[SCSI] libsas: remove expander from dev list on error", where Luben noted [1]: > 2/ We have unlocked list manipulations in sas_ex_discover_end_dev(), > sas_unregister_common_dev(), and sas_ex_discover_end_dev() Yes, I can see that and that is very unfortunate. [1]: http://marc.info/?l=linux-scsi&m=131480962006471&w=2 Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02[SCSI] isci: atapi supportDan Williams
Based on original implementation from Jiangbi Liu and Maciej Trela. ATAPI transfers happen in two-to-three stages. The two stage atapi commands are those that include a dma data transfer. The data transfer portion of these operations is handled by the hardware packet-dma acceleration. The three-stage commands do not have a data transfer and are handled without hardware assistance in raw frame mode. stage1: transmit host-to-device fis to notify the device of an incoming atapi cdb. Upon reception of the pio-setup-fis repost the task_context to perform the dma transfer of the cdb+data (go to stage3), or repost the task_context to transmit the cdb as a raw frame (go to stage 2). stage2: wait for hardware notification of the cdb transmission and then go to stage 3. stage3: wait for the arrival of the terminating device-to-host fis and terminate the command. To keep the implementation simple we only support ATAPI packet-dma protocol (for commands with data) to avoid needing to handle the data transfer manually (like we do for SATA-PIO). This may affect compatibility for a small number of devices (see ATA_HORKAGE_ATAPI_MOD16_DMA). If the data-transfer underruns, or encounters an error the device-to-host fis is expected to arrive in the unsolicited frame queue to pass to libata for disposition. However, in the DONE_UNEXP_FIS (data underrun) case it appears we need to craft a response. In the DONE_REG_ERR case we do receive the UF and propagate it to libsas. Signed-off-by: Maciej Trela <maciej.trela@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02[SCSI] libsas: fix try_test_sas_gpio_gp_bit() build errorDan Williams
If the user has disabled CONFIG_SCSI_SAS_HOST_SMP then libsas drivers will not be receiving smp-gpio frames and do not need this lookup code. Reported-by: Randy Dunlap <rdunlap@xenotime.net> Tested-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02[SCSI] libsas: Allow expander T-T attachmentsLuben Tuikov
Allow expander table-to-table attachments for expanders that support it. Signed-off-by: Luben Tuikov <ltuikov@yahoo.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-09-22[SCSI] libsas: sgpio write supportDan Williams
Add SFF-8485 v0.7 / SAS-1 smp-write-gpio register support to libsas. Defer SAS-2 support unless/until it defines an sgpio interface. Minimum implementation needed to get the lights blinking. try_test_sas_gpio_gp_bit() provides a common method to parse the incoming write data (raw bitstream), and the to_sas_gpio_gp_bit() helper routine can be used as a basis for the set/clear operations for the 'read' implementation. Host implementations parse as many bits (ODx.[012]) as are locally supported and report the number of registers successfully written. If the submitted data overruns the internal number of registers available report the write as a success with the number of bytes remaining reported in ->resid_len. Example (assuming an active backplane) set the "identify" pattern for the first 21 devices: smp_write_gpio --count=2 --data=92,49,24,92,24,92,49,24 -t 4 --index=1 /dev/bsg/sas_hostX Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-27[SCSI] libsas: export sas_alloc_task()Dan Williams
Now that isci has added a 3rd open coded user of this functionality just share the libsas version. Acked-by: Jack Wang <jack_wang@usish.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-05-26[SCSI] libsas: Add option for SATA soft resetDave Jiang
This allows a libsas driver to optionally provide a soft reset handler for libata to drive. The isci driver allows software to control the assertion/deassertion of SRST. [jejb: checkpatch.pl fixes] Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <jbottomley@parallels.com>