Commit Graph

152 Commits

Author SHA1 Message Date
Hannes Reinecke d2d06d4fe0 scsi_dh_rdac: always retry MODE SELECT on command lock violation
If MODE SELECT returns with sense '05/91/36' (command lock violation)
it should always be retried without counting the number of retries.
During an HBA upgrade or similar circumstances one might see a flood
of MODE SELECT command from various HBAs, which will easily trigger
the sense code and exceed the retry count.

Cc: <stable@vger.kernel.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-02-04 22:26:06 -05:00
Hannes Reinecke 23211c1e7a scsi_dh_alua: Remove stale variables
With commit 83ea0e5e35 ("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>
2015-12-07 20:11:25 -05:00
Hannes Reinecke 83ea0e5e35 scsi_dh_alua: use scsi_vpd_tpg_id()
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>
2015-12-02 16:59:01 -05:00
Hannes Reinecke e2d817db32 scsi_dh_alua: simplify sense code handling
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>
2015-12-02 16:38:20 -05:00
Hannes Reinecke ad0ea64c53 scsi_dh_alua: rework alua_check_tpgs() to return the tpgs mode
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>
2015-12-02 16:37:55 -05:00
Hannes Reinecke a7089770b9 scsi_dh_alua: use unaligned access macros
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>
2015-12-02 16:37:14 -05:00
Hannes Reinecke 6c4fc04491 scsi_dh_alua: use flag for RTPG extended header
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>
2015-12-02 16:36:44 -05:00
Hannes Reinecke dac173ee7e scsi_dh_alua: fixup description of stpg_endio()
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>
2015-12-02 16:35:31 -05:00
Hannes Reinecke 5597cafc7a scsi_dh_alua: return standard SCSI return codes in submit_rtpg
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>
2015-12-02 16:34:55 -05:00
Hannes Reinecke 80bd68d6bf scsi_dh_alua: use standard logging functions
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>
2015-12-02 16:34:26 -05:00
Hannes Reinecke d3692a3d13 scsi_dh_alua: sanitze sense code handling
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>
2015-12-02 16:33:21 -05:00
Hannes Reinecke 6cc05d451c scsi_dh_alua: improved logging
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>
2015-12-02 16:32:49 -05:00
Hannes Reinecke 9b80dcec41 scsi_dh_alua: Use vpd_pg83 information
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>
2015-12-02 16:31:56 -05:00
Hannes Reinecke db5a6a601b scsi_dh_alua: Disable ALUA handling for non-disk devices
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>
2015-12-02 16:30:46 -05:00
Christoph Hellwig ee14c674e8 scsi_dh: kill struct scsi_dh_data
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>
2015-08-28 13:14:57 -07:00
Christoph Hellwig d95dbff2a4 scsi_dh: move device matching to the core code
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>
2015-08-28 13:14:56 -07:00
Christoph Hellwig 086b91d052 scsi_dh: integrate into the core SCSI code
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>
2015-08-28 13:14:56 -07:00
Christoph Hellwig daaa858b7a scsi_dh: move to drivers/scsi
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>
2015-08-28 13:14:55 -07:00
Christoph Hellwig 566079c849 dm-mpath, scsi_dh: request scsi_dh modules in scsi_dh, not dm-mpath
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>
2015-08-28 13:14:55 -07:00
Christoph Hellwig 1bab0de027 dm-mpath, scsi_dh: don't let dm detach device handlers
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>
2015-08-28 13:14:54 -07:00
Mike Christie 28072ad50c scsi: fix device handler detach oops
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>
2015-02-02 13:45:28 +01:00
Christoph Hellwig 1d5203284d scsi: handle more device handler setup/teardown in common code
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>
2014-11-12 11:19:36 +01:00
Christoph Hellwig 1f12ffa514 scsi: device handlers must have attach and detach methods
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12 11:19:33 +01:00
Christoph Hellwig a64d01dcf8 scsi: remove struct scsi_dh_devlist
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>
2014-11-12 11:19:29 +01:00
Christoph Hellwig cd37743fc9 scsi: use container_of to get at device handler private data
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12 11:19:25 +01:00
Christoph Hellwig 27c888f0bb scsi_dh: get module reference outside of device handler
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>
2014-11-12 11:19:22 +01:00
Christoph Hellwig 0b9c08442c scsi_dh_hp_sw: fix return value on failed allocation
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12 11:19:17 +01:00
wenxiong@linux.vnet.ibm.com 333b2448cf scsi: TUR path is down after adapter gets reset with multipath
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>
2014-11-10 15:23:27 +01:00
Joe Lawrence a492f07545 block,scsi: fixup blk_get_request dead queue scenarios
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>
2014-08-28 10:03:46 -06:00
Jens Axboe f27b087b81 block: add blk_rq_set_block_pc()
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>
2014-06-06 07:57:37 -06:00
Stewart, Sean a8e5a2d593 [SCSI] scsi_dh_alua: ALUA handler attach should succeed while TPG is 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
c0d289b3e5 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 11:19:33 +01:00
Stewart, Sean c20ee7b56e [SCSI] scsi_dh_alua: ALUA check sense should retry device internal reset 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 11:14:18 +01:00
Stewart, Sean 4df01b06ae [SCSI] scsi_dh_rdac: Add new IBM 1813 product id to rdac devlist
Signed-off-by: Sean Stewart <Sean.Stewart@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-10-25 09:57:55 +01:00
Stewart, Sean 7a3ad3920d [SCSI] scsi_dh_alua: Add module parameter to allow failover to non preferred 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>
2013-04-11 16:00:31 -07:00
Mike Christie 27db682bf0 [SCSI] scsi_dh_alua: fix stpg sense handling
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>
2013-04-09 20:55:21 -07:00
Kees Cook 2a570a4917 drivers/scsi/device_handler: remove depends on CONFIG_EXPERIMENTAL
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>
2013-01-21 14:52:45 -08:00
Bart Van Assche e47f8976d8 [SCSI] scsi_dh_alua: Enable STPG for unavailable ports
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 12:21:56 +04:00
Moger, Babu 1315da30da [SCSI] scsi_dh_rdac : minor return fix for rdac
Signed-off-by: Babu Moger <babu.moger@netapp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-09-24 12:11:03 +04:00
Moger, Babu 35204772ea [SCSI] scsi_dh_rdac : Consolidate rdac strings together
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 12:11:03 +04:00
Moger, Babu e7ba29d633 [SCSI] scsi_dh_rdac: Add a new netapp vendor/product string
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>
2012-09-24 12:11:03 +04:00
Mike Snitzer 7e8a74b177 [SCSI] scsi_dh: add scsi_dh_attached_handler_name
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 08:58:42 +01:00
Bart Van Assche bb2c94a3a6 [SCSI] scsi_dh_alua: Re-enable STPG for unavailable ports
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 08:58:36 +01:00
Rob Evers bc97f4bb44 [SCSI] scsi_dh_alua: backoff alua rtpg retry linearly vs. geometrically
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 08:58:33 +01:00
Rob Evers 8e67ce6072 [SCSI] scsi_dh_alua: retry alua rtpg extended header for illegal request 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 08:58:33 +01:00
Rob Evers 3588c5a21a [SCSI] scsi_dh_alua: implement 'implied transition timeout'
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>
2012-07-20 08:58:32 +01:00
Moger, Babu 72d9e0f383 [SCSI] scsi_dh_alua: Optimize the STPG command
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 19:28:18 +01:00
Moger, Babu dcd3a754b8 [SCSI] scsi_dh_alua: Store the PREF bit from RTPG
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 19:28:13 +01:00
Moger, Babu 4335d092a1 [SCSI] scsi_dh_alua: Inroduce the set_params interface scsi_dh_alua handler
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>
2012-04-23 19:28:07 +01:00
Moger, Babu 3569e5374d [SCSI] scsi_dh_rdac: Fix for unbalanced reference count
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>
2012-02-22 12:15:19 -06:00
Moger, Babu 410f02d813 [SCSI] scsi_dh_alua: Retry the check-condition in case Mode Parameters Changed
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>
2012-01-10 17:01:24 -06:00