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2015-12-08scsi_dh_alua: Remove stale variablesHannes Reinecke1-2/+0
With commit 83ea0e5e3501 ("scsi_dh_alua: use scsi_vpd_tpg_id()") these variables became obsolete, but weren't removed. [mkp: Fixed checkpatch warning] Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: use scsi_vpd_tpg_id()Hannes Reinecke1-31/+6
Use the common function 'scsi_vpd_tpg_id()' instead of open-coding it in scsi_dh_alua. [mkp: Applied by hand] Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: simplify sense code handlingHannes Reinecke1-28/+17
Most sense code is already handled in the generic code, so we shouldn't be adding special cases here. However, when doing so we need to check for unit attention whenever we're sending an internal command. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ewan Milne <emilne@redhat.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>
2015-12-03scsi_dh_alua: rework alua_check_tpgs() to return the tpgs modeHannes Reinecke1-14/+11
Instead of returning an error code in alua_check_tpgs() we should rather return the tpgs mode directly and have a cleaner syntax. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: use unaligned access macrosHannes Reinecke1-15/+8
Use 'get_unaligned_XX' and 'put_unaligned_XX' instead of open-coding it. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.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>
2015-12-03scsi_dh_alua: use flag for RTPG extended headerHannes Reinecke1-8/+7
We should be using a flag when RTPG extended header is not supported, that saves us sending RTPG twice for older arrays. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: fixup description of stpg_endio()Hannes Reinecke1-4/+2
Fixup copy-and-paste error in the description of stpg_endio(). Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: return standard SCSI return codes in submit_rtpgHannes Reinecke1-16/+17
Fixup submit_rtpg() to always return a standard SCSI return code. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ewan Milne <emilne@redhat.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: use standard logging functionsHannes Reinecke1-14/+13
Use standard logging functions instead of hand-crafted ones. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ewan Milne <emilne@redhat.com> Reviewed-by: Bart Van Assche <bvanassche@sandisk.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: sanitze sense code handlingHannes Reinecke1-11/+7
The only check for a valid sense code is calling scsi_normalize_sense() and check the return value. So drop the pointless checks and rely on scsi_normalize_sense() to figure out if the sense code is valid. With that we can also remove the 'senselen' field. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com> Reviewed-by: Bart van Assche <bvanassche@sandisk.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-12-03scsi_dh_alua: improved loggingHannes Reinecke1-2/+8
Issue different logging messages if ALUA is not supported or the TPGS setting is invalid. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.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>
2015-12-03scsi_dh_alua: Use vpd_pg83 informationHannes Reinecke1-69/+18
The SCSI device now has the VPD page 0x83 information attached, so there is no need to query it again. [mkp: Fixed a checkpatch warning] Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.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>
2015-12-03scsi_dh_alua: Disable ALUA handling for non-disk devicesHannes Reinecke1-0/+12
Non-disk devices might support ALUA, but the firmware implementation is untested and frequently broken. As we're don't actually need it disable ALUA support for non-disk device for now. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-08-28scsi_dh: kill struct scsi_dh_dataChristoph Hellwig4-65/+44
Add a ->handler and a ->handler_data field to struct scsi_device and kill this indirection. Also move struct scsi_device_handler to scsi_dh.h so that changes to it don't require rebuilding every SCSI LLDD. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-28scsi_dh: move device matching to the core codeChristoph Hellwig4-115/+0
Add a single list of devices that need non-ALUA device handlers to the core scsi_dh code so that we can autoload the modules for them at probe time. While this is a little ugly in terms of architecture it actually significantly simplifies the code in addition to the new autoloading functionality. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-28scsi_dh: integrate into the core SCSI codeChristoph Hellwig2-2/+1
Stop building scsi_dh as a separate module and integrate it fully into the core SCSI code with explicit callouts at bus scan time. For now the callouts are placed at the same point as the old bus notifiers were called, but in the future we will be able to look at ALUA INQUIRY data earlier on. Note that this also means that the device handler modules need to be loaded by the time we scan the bus. The next patches will add support for autoloading device handlers at bus scan time to make sure they are always loaded if they are enabled in the kernel config. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-28scsi_dh: move to drivers/scsiChristoph Hellwig1-571/+0
Prepare for building scsi_dh.c into the core SCSI module by moving it to drivers/scsi. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-28dm-mpath, scsi_dh: request scsi_dh modules in scsi_dh, not dm-mpathChristoph Hellwig1-17/+19
This way we can reused the same code any attachment method, not just those requested from dm-mpath. [jejb: fixup checkpatch error] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-28dm-mpath, scsi_dh: don't let dm detach device handlersChristoph Hellwig1-74/+22
While allowing dm-mpath to attach device handlers is a functionality we need for backwards compatibility reason there is no reason to reference count them and detach them if dm-mpath stops using the device for some reason. If the device handler works for the given device it can just stay attached, and we can take the retain_hw_handler codepath. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Hannes Reinecke <hare@Suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-02-02scsi: fix device handler detach oopsMike Christie1-1/+2
This fixes a regression caused by commit 1d5203 ("scsi: handle more device handler setup/teardown in common code"). The bug is that the alua detach() callout will try to access the sddev->scsi_dh_data, but we have already set it to NULL. This patch moves the clearing of that field to after detach() is called. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-12scsi: handle more device handler setup/teardown in common codeChristoph Hellwig5-166/+87
Move all code to set up and tear down sdev->scsi_dh_data to common code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi: device handlers must have attach and detach methodsChristoph Hellwig1-12/+13
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi: remove struct scsi_dh_devlistChristoph Hellwig3-6/+12
All drivers now do their own matching, so there is no more need to expose a device list as part of the interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi: use container_of to get at device handler private dataChristoph Hellwig4-60/+37
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi_dh: get module reference outside of device handlerChristoph Hellwig5-25/+22
We need to grab a reference to the module before calling the attach routines to avoid a small race vs module removal. It also cleans up the code significantly as a side effect. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi_dh_hp_sw: fix return value on failed allocationChristoph Hellwig1-1/+1
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-10scsi: TUR path is down after adapter gets reset with multipathwenxiong@linux.vnet.ibm.com1-0/+7
This patch fixes an issue with multipath ipr SAS devices which require a start unit command to be issued following an adapter reset. Without this patch, paths get marked failed following an adapter reset and since the error handler never gets invoked to issue the start unit, the paths are never recovered. Returning FAILED for this case ensures the error handler wakes up to issue the start unit. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Tested-by: Wen Xiong <wenxiong@linux.vnet.ibm.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-08-28block,scsi: fixup blk_get_request dead queue scenariosJoe Lawrence4-5/+5
The blk_get_request function may fail in low-memory conditions or during device removal (even if __GFP_WAIT is set). To distinguish between these errors, modify the blk_get_request call stack to return the appropriate ERR_PTR. Verify that all callers check the return status and consider IS_ERR instead of a simple NULL pointer check. For consistency, make a similar change to the blk_mq_alloc_request leg of blk_get_request. It may fail if the queue is dead, or the caller was unwilling to wait. Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Jiri Kosina <jkosina@suse.cz> [for pktdvd] Acked-by: Boaz Harrosh <bharrosh@panasas.com> [for osd] Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-06block: add blk_rq_set_block_pc()Jens Axboe4-5/+5
With the optimizations around not clearing the full request at alloc time, we are leaving some of the needed init for REQ_TYPE_BLOCK_PC up to the user allocating the request. Add a blk_rq_set_block_pc() that sets the command type to REQ_TYPE_BLOCK_PC, and properly initializes the members associated with this type of request. Update callers to use this function instead of manipulating rq->cmd_type directly. Includes fixes from Christoph Hellwig <hch@lst.de> for my half-assed attempt. Signed-off-by: Jens Axboe <axboe@fb.com>
2013-10-25[SCSI] scsi_dh_alua: ALUA handler attach should succeed while TPG is ↵Stewart, Sean1-10/+16
transitioning During testing, it was discovered that when a device tries to attach to the alua handler while in TPG state of transitioning, the alua_rtpg function will wait for it to exit the state before allowing it to continue. As a result, if the 60 second timeout expires, the alua handler will not attach to the device. To fix this, I have introduced an input argument to alua_rtpg called wait_for_transition. The idea is that it will wait for the transition to complete before an activation (because the current TPG state has some bearing in that case), but during a discovery if it is transitioning, it will not wait, and will store the state as standby for the time being. I believe the precedent exists for this from commit c0d289b3e59577532c45ee9110ef81bd7b341272 Since if the device reports a state of transitioning, it can transition to other more valid states, and it has been established TPGS is supported on the device, if it is attaching. Signed-off-by: Sean Stewart <Sean.Stewart@netapp.com> Acked-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-10-25[SCSI] scsi_dh_alua: ALUA check sense should retry device internal reset ↵Stewart, Sean1-0/+5
unit attention When the scsi_dh_alua handler issues an RTPG during initialization, if it gets 0x06/0x29/0x04 as the sense, it will fail to attach the handler. NetApp E-Series returns 0x29/0x00 for power on, and 0x29/0x04 for conditions that cause the controller to reboot again. These conditions should be treated identically within the handler. Signed-off-by: Sean Stewart <Sean.Stewart@netapp.com> Acked-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-10-25[SCSI] scsi_dh_rdac: Add new IBM 1813 product id to rdac devlistStewart, Sean1-0/+1
Signed-off-by: Sean Stewart <Sean.Stewart@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-12[SCSI] scsi_dh_alua: Add module parameter to allow failover to non preferred ↵Stewart, Sean1-0/+7
path without STPG Resending with requested rewording of the parameter description. Currently ALUA device handler sends STPG command during failover and failback. Failover can be optimized by implicit failover (by not to sending STPG command), when 1 is passed as hwhandler parameter in multipath.conf. ex "2 alua 1". We may need to pass the parameter through module param for alua device handler to optimize failover if incase retain_attached_hwhandler set in multipath.conf and hwhandler is set with non-tpgs device handler ex: '1 rdac'. [jejb: fix up whitespace and other issues] Signed-off-by: Vijay Chauhan <vijay.chauhan@netapp.com> Signed-off-by: Sean Stewart <Sean.Stewart@netapp.com> Acked-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-10[SCSI] scsi_dh_alua: fix stpg sense handlingMike Christie1-4/+6
For the stpg_endio path we are not evaluating the sense. The bug is that 1. The error value is set to -EIO when there is sense, so we hit the first error check and always return SCSI_DH_IO. 2. h->senselen is set to zero in submit_stpg. It is not later set to req->sense_len like in the synchrounous exection paths, so we must check the req->sense_len field. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-01-22drivers/scsi/device_handler: remove depends on CONFIG_EXPERIMENTALKees Cook1-2/+2
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a while now and is almost always enabled by default. As agreed during the Linux kernel summit, remove it from any "depends on" lines in Kconfigs. CC: "James E.J. Bottomley" <JBottomley@parallels.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-24[SCSI] scsi_dh_alua: Enable STPG for unavailable portsBart Van Assche1-2/+1
A quote from SPC-4: "While in the unavailable primary target port asymmetric access state, the device server shall support those of the following commands that it supports while in the active/optimized state: [ ... ] d) SET TARGET PORT GROUPS; [ ... ]". Hence enable sending STPG to a target port group that is in the unavailable state. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Acked-by: Hannes Reinecke <hare@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-09-24[SCSI] scsi_dh_rdac : minor return fix for rdacMoger, Babu1-1/+1
Signed-off-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-09-24[SCSI] scsi_dh_rdac : Consolidate rdac strings togetherMoger, Babu1-15/+4
This patch consolidates the strings together. Purpose is to remove minor product strings extensions. That way the future products with similar strings should not require change here. Signed-off-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-09-24[SCSI] scsi_dh_rdac: Add a new netapp vendor/product stringMoger, Babu1-5/+6
This patch adds a new vendor/product strings for netapp E series product. Also consolidated the strings together with similar names. Signed-off-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] scsi_dh: add scsi_dh_attached_handler_nameMike Snitzer1-2/+36
Introduce scsi_dh_attached_handler_name() to retrieve the name of the scsi_dh that is attached to the scsi_device associated with the provided request queue. Returns NULL if a scsi_dh is not attached. Also, fix scsi_dh_{attach,detach} function header comments to document @q rather than @sdev. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Tested-by: Babu Moger <babu.moger@netapp.com> Reviewed-by: Chandra Seetharaman <sekharan@us.ibm.com> Acked-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] scsi_dh_alua: Re-enable STPG for unavailable portsBart Van Assche1-1/+1
A quote from SPC-4: "While in the unavailable primary target port asymmetric access state, the device server shall support those of the following commands that it supports while in the active/optimized state: [ ... ] d) SET TARGET PORT GROUPS; [ ... ]". Hence re-enable sending STPG to a target port group that is in the unavailable state. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] scsi_dh_alua: backoff alua rtpg retry linearly vs. geometricallyRob Evers1-2/+2
Currently the backoff algorithm for when to retry alua rtpg requests progresses geometrically as so: 2, 4, 8, 16, 32, 64... seconds. This progression can lead to un-needed delay in retrying alua rtpg requests when the rtpgs are delayed. A less aggressive backoff algorithm that is additive would not lead to such large jumps when delays start getting long, but would backoff linearly: 2, 4, 6, 8, 10... seconds. Signed-off-by: Martin George <marting@netapp.com> Signed-off-by: Rob Evers <revers@redhat.com> Reviewed-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] scsi_dh_alua: retry alua rtpg extended header for illegal request ↵Rob Evers1-3/+23
response Some storage arrays are known to return 'illegal request' when an rtpg extended header request is made. T10 says the array should ignore the bit, and return the non-extended rtpg as the array doesn't support the request. Working around this by retrying the rtpg request without the extended header bit set when the extended rtpg request results in illegal request. Signed-off-by: Rob Evers <revers@redhat.com> Reviewed-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20[SCSI] scsi_dh_alua: implement 'implied transition timeout'Rob Evers1-5/+36
During alua transitions, an array can return transitioning status in response to rtpg requests. These requests get retried for a maximum of 60 seconds by default before timing out. Sometimes this timeout isn't sufficient to allow the array to complete the transition. T10-spc4 addresses this under 'Report Target Port Groups' command. This update retrieves the timeout value from the storage array if available and retries the transitioning rtpgs for up to the 'implied transitioning timeout' value Signed-off-by: Rob Evers <revers@redhat.com> Reviewed-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23[SCSI] scsi_dh_alua: Optimize the STPG commandMoger, Babu1-3/+26
This patch optimizes the set target port group(STPG) command. During our testing, we found that it is not optimal to send stpg command every time the path group switch happens. This patch uses PREF (preferred target port) bit with combination of flags passed by multipath user level tool to optimize this behaviour. If PREF bit is set then it issues a STPG command, otherwise it will let implicit transfer take place. By default there is no change in the behaviour. User tool needs to pass the parameter to make this change take effect. Patch has been tested on NetApp E series storage. Signed-off-by: Babu Moger <babu.moger@netapp.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23[SCSI] scsi_dh_alua: Store the PREF bit from RTPGMoger, Babu1-1/+4
PREF bit indicates preferred target port group for accessing a logical unit. This bit is used to optimize the STPG command handling. Signed-off-by: Babu Moger <babu.moger@netapp.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23[SCSI] scsi_dh_alua: Inroduce the set_params interface scsi_dh_alua handlerMoger, Babu1-0/+36
Handler expects only one parameter to set the flag ALUA_OPTIMIZE_STPG. This flag is used to optimize the STPG behaviour. There is no change in behaviour by default. For example, to set the flag pass the following parameters from multipath.conf hardware_handler "2 alua 1" Signed-off-by: Babu Moger <babu.moger@netapp.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-22[SCSI] scsi_dh_rdac: Fix for unbalanced reference countMoger, Babu1-11/+14
This patch fixes an unbalanced refcount issue. Elevating the lock for both kref_put and also for controller node deletion. Previously, controller deletion was protected but the not the kref_put. This was causing the other thread to pick up the controller structure which was already kref'd zero. This was causing the following WARN_ON and also sometimes panic. WARNING: at lib/kref.c:43 kref_get+0x2d/0x30() (Not tainted) Hardware name: IBM System x3655 -[7985AC1]- Modules linked in: fuse scsi_dh_rdac autofs4 nfs lockd fscache nfs_acl auth_rpcgss sunrpc 8021q garp stp llc ipv6 ib_srp(U) scsi_transport_srp scsi_tgt ib_cm(U) ib_sa(U) ib_uverbs(U) ib_umad(U) mlx4_ib(U) mlx4_core(U) ib_mthca(U) ib_mad(U) ib_core(U) dm_mirror dm_region_hash dm_log dm_round_robin dm_multipath uinput bnx2 ses enclosure sg ibmpex ibmaem ipmi_msghandler serio_raw k8temp hwmon amd64_edac_mod edac_core edac_mce_amd shpchp i2c_piix4 ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif sata_svw pata_acpi ata_generic pata_serverworks aacraid radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core dm_mod [last unloaded: freq_table] Pid: 13735, comm: srp_daemon Not tainted 2.6.32-71.el6.x86_64 #1 Call Trace: [<ffffffff8106b857>] warn_slowpath_common+0x87/0xc0 [<ffffffff8106b8aa>] warn_slowpath_null+0x1a/0x20 [<ffffffff8125c39d>] kref_get+0x2d/0x30 [<ffffffffa01b4029>] rdac_bus_attach+0x459/0x580 [scsi_dh_rdac] [<ffffffff8135232a>] scsi_dh_handler_attach+0x2a/0x80 [<ffffffff81352c7b>] scsi_dh_notifier+0x9b/0xa0 [<ffffffff814cd7a5>] notifier_call_chain+0x55/0x80 [<ffffffff8109711a>] __blocking_notifier_call_chain+0x5a/0x80 [<ffffffff81097156>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff8132bec5>] device_add+0x515/0x640 [<ffffffff813329e4>] ? attribute_container_device_trigger+0xc4/0xe0 [<ffffffff8134f659>] scsi_sysfs_add_sdev+0x89/0x2c0 [<ffffffff8134d096>] scsi_probe_and_add_lun+0xea6/0xed0 [<ffffffff8134beb2>] ? scsi_alloc_target+0x292/0x2d0 [<ffffffff8134d1e1>] __scsi_scan_target+0x121/0x750 [<ffffffff811df806>] ? sysfs_create_file+0x26/0x30 [<ffffffff8132b759>] ? device_create_file+0x19/0x20 [<ffffffff81332838>] ? attribute_container_add_attrs+0x78/0x90 [<ffffffff814b008c>] ? klist_next+0x4c/0xf0 [<ffffffff81332e30>] ? transport_configure+0x0/0x20 [<ffffffff813329e4>] ? attribute_container_device_trigger+0xc4/0xe0 [<ffffffff8134df40>] scsi_scan_target+0xd0/0xe0 [<ffffffffa02f053a>] srp_create_target+0x75a/0x890 [ib_srp] [<ffffffff8132a130>] dev_attr_store+0x20/0x30 [<ffffffff811df145>] sysfs_write_file+0xe5/0x170 [<ffffffff8116c818>] vfs_write+0xb8/0x1a0 [<ffffffff810d40a2>] ? audit_syscall_entry+0x272/0x2a0 [<ffffffff8116d251>] sys_write+0x51/0x90 [<ffffffff81013172>] system_call_fastpath+0x16/0x1b Signed-off-by: Babu Moger <babu.moger@netapp.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-01-11[SCSI] scsi_dh_alua: Retry the check-condition in case Mode Parameters ChangedMoger, Babu1-0/+5
This patch adds a check-condition in scsi_dh_alua handler for a retry. Sometimes, I have seen attach failing due to this check-condition with following error messages on NetApp E series storage. Dec 7 15:31:01 nilgiris kernel: [102979.696673] scsi 3:0:2:9: alua: port group 00 rel port 01 Dec 7 15:31:01 nilgiris kernel: [102979.697082] scsi 3:0:2:9: alua: rtpg failed with 8000002 Dec 7 15:31:01 nilgiris kernel: [102979.697086] scsi 3:0:2:9: alua: rtpg sense code 06/2a/01 Dec 7 15:31:01 nilgiris kernel: [102979.697088] scsi 3:0:2:9: alua: not attached Signed-off-by: Babu Moger <babu.moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-01-11[SCSI] scsi_dh_rdac: Fix error pathRichard Weinberger1-0/+2
If create_singlethread_workqueue() failes, rdac_init should fail too. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: "Moger, Babu" <Babu.Moger@netapp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>