During device discovery read capacity fails with 0x068b02 and sets the
device size to 0. As a reason any I/O submitted to this path gets
killed at sd_prep_fn with BLKPREP_KILL. This patch is to retry for
0x068b02
Signed-off-by: NVijay Chauhan <vijay.chauhan@lsi.com>
Acked-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

[jejb: fixed whitespace damage]
Signed-off-by: NBabu Moger <Babu.Moger@lsi.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

When the mode select sent to the controller fails with the retryable
error, it is better to retry the mode_select from the hardware handler
itself, instead of propagating the failure to dm-multipath.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] scsi_dh: Make sure the state of a path is set properly when controller is swapped from passive to active

When the controller ownership is changed (from passive to active),
check_ownership() doesn't set the state of the device to ACTIVE.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Reported-by: N"Moger, Babu" <Babu.Moger@lsi.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Set the path state to be passive when we learn that the controller does
not own the path to the LUN.

This will avoid sending even a single i/o thru the passive path at the
probe time.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Multipath is best at handling transport errors. If it gets a device
error then there is not much the multipath layer can do. It will just
access the same device but from a different path.

This patch breaks up failfast into device, transport and driver errors.
The multipath layers (md and dm mutlipath) only ask the lower levels to
fast fail transport errors. The user of failfast, read ahead, will ask
to fast fail on all errors.

Note that blk_noretry_request will return true if any failfast bit
is set. This allows drivers that do not support the multipath failfast
bits to continue to fail on any failfast error like before. Drivers
like scsi that are able to fail fast specific errors can check
for the specific fail fast type. In the next patch I will convert
scsi.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Add Dell Powervault storage arrays into device list of rdac device
handler.
Signed-off-by: NYanqing Liu <yanqing_liu@dell.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

blk_get_request initializes rq->cmd (rq_init does) so the users don't
need to do that.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Change scsi_dh check_sense functions to return ADD_TO_MLQUEUE
to allow retries to occur without restriction of blk_noretry_request
check.
Signed-off-by: NMike Anderson <andmike@linux.vnet.ibm.com>
Acked-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

lun_state need to be initialized inside check_ownership().
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

RDAC storage controller doesn't seem to use the scsilun format. It uses
only the last byte for LUN.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

This patch makes several needlessly global struct scsi_dh_devlist's
static.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch updates the RDAC device handler to
refuse to attach to devices not supporting the
RDAC vpd pages.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Instead of having each and every driver implement its own
device table scanning code we should rather implement a common
routine and scan the device tables there.
This allows us also to implement a general notifier chain
callback for all device handler instead for one per handler.

[sekharan: Fix rejections caused by conflicting bug fix]
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Before accessing the device data structure in hardware handlers,
make sure it is a indeed a sdev device.

Yinghai Lu <yhlu.kernel@gmail.com> found the bug on Jul 16, 2008,
and later tested/verified the following fix.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch provides the device handler to support the LSI RDAC SCSI
based storage devices.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>