[jejb: fixed whitespace damage]
Signed-off-by: Babu Moger <Babu.Moger@lsi.com>
Signed-off-by: James 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: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

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: Chandra Seetharaman <sekharan@us.ibm.com>
Reported-by: "Moger, Babu" <Babu.Moger@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

The test-unit-ready portion of this patch was causing boots to fail on
my test machine (as in http://lkml.org/lkml/2008/12/5/161). With this
patch in place, the system is booting reliably.

Mike Anderson found the same problem in the hp_hw_start_stop code,
and I applied the same solution in cdrom_read_cdda_bpc.

Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Cc: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.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: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

We do not need to set REQ_NOMERGE because when the module calls
blk_execute_rq -> blk_execute_rq_nowait, blk_execute_rq_nowait sets
it for us. This brings all the modules in sync for those bits.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James 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: Mike Christie <michaelc@cs.wisc.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

On Mon, 2008-09-22 at 14:56 -0700, akpm@linux-foundation.org wrote:
> From: Andrew Morton <akpm@linux-foundation.org>
>
> s390:
>
> drivers/scsi/device_handler/scsi_dh_emc.c: In function 'parse_sp_info_reply':
> drivers/scsi/device_handler/scsi_dh_emc.c:179: warning: comparison is always false due to limited range of data type
>
> because chars are unsigned, I assume.

Fix by making csdev->buffer explicitly an unsigned char and dropping
the < 0 test.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

Add Dell Powervault storage arrays into device list of rdac device
handler.

Signed-off-by: Yanqing Liu <yanqing_liu@dell.com>
Signed-off-by: James 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: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>