1
Commit Graph

97739 Commits

Author SHA1 Message Date
Mike Christie
d82ff9be73 [SCSI] iscsi class: add endpoint class
Add sysfs representation for the endpoint, so userspace can match the
host and session to the endpoint. This will allow us to set the host's
parent correctly at host creation time.

The next patches will convert tcp and iser, and fix iser's dma_mask
bug.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:20 -05:00
Mike Christie
7970634b81 [SCSI] iscsi class: user device_for_each_child instead of duplicating session list
Currently we duplicate the list of sessions, because we were using the
test for if a session was on the host list to indicate if the session
was bound or unbound. We can instead use the target_id and fix up
the class so that drivers like bnx2i do not have to manage the target id
space.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:20 -05:00
Mike Christie
2261ec3d68 [SCSI] iser: handle iscsi_cmd_task rename
This handles the iscsi_cmd_task rename and renames
the iser cmd task to iser task.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:20 -05:00
Mike Christie
135a8ad4e0 [SCSI] iscsi_tcp: handle iscsi_cmd_task rename
This converts iscsi_tcp to use the iscsi_task name.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:20 -05:00
Mike Christie
9c19a7d038 [SCSI] libiscsi: rename iscsi_cmd_task to iscsi_task
This is the second part of the iscsi task merging, and
all it does it rename iscsi_cmd_task to iscsi_task and
mtask/ctask to just task.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:19 -05:00
Mike Christie
2747fdb257 [SCSI] iser: convert ib_iser to support merged tasks
Convert ib_iser to support merged tasks.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:19 -05:00
Mike Christie
fbc514b4e2 [SCSI] iscsi_tcp: convert iscsi_tcp to support merged tasks
Convert iscsi_tcp to support merged tasks.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:19 -05:00
Mike Christie
3e5c28ad03 [SCSI] libiscsi: merge iscsi_mgmt_task and iscsi_cmd_task
There is no need to have the mgmt and cmd tasks separate
structs. It used to save a lot of memory when we overprealocated
memory for tasks, but the next patches will set up the
driver so in the future they can use a mempool or some other
common scsi command allocator and common tagging.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:19 -05:00
Mike Christie
052d014485 [SCSI] libiscsi: modify libiscsi so it supports offloaded data paths
This patch modifies libiscsi, so drivers like bnx2i and iser can execute
a command from queuecommand/send_pdu instead of having to be queued to
be run in a workq.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:18 -05:00
Mike Christie
0af967f5d4 [SCSI] libiscsi, iscsi_tcp, iser: add session cmds array accessor
Currently to get a ctask from the session cmd array, you have to
know to use the itt modifier. To make this easier on LLDs and
so in the future we can easilly kill the session array and use
the host shared map instead, this patch adds a nice wrapper
to strip the itt into a session->cmds index and return a ctask.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:18 -05:00
Mike Christie
b40977d95f [SCSI] iser: fix handling of scsi cmnds during recovery.
After the stop_conn callback has returned the LLD should not
touch the scsi cmds. iscsi_tcp and libiscsi use the
conn->recv_lock and suspend_rx field to halt recv path
processing, but iser does not have any protection.

This patch modifies iser so that userspace can just
call the ep_disconnect callback, which will halt
all recv IO, before calling the stop_conn callback so
we do not have to worry about the conn->recv_lock and
suspend rx field. iser just needs to stop the send side
from accessing the ib conn.

Fixup to handle when the ep poll fails and ep disconnect
is called from Erez.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:17 -05:00
Mike Christie
5af3e91d23 [SCSI] iscsi: modify iscsi printk so it can take driver data pointers
Some drivers want to be able to just pass in the driver data pointers
to the iscsi objects. To enable this we need the iscsi printk macro
to cast the object.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:17 -05:00
Mike Christie
5d91e209fb [SCSI] iscsi: remove session/conn_data_size from iscsi_transport
This removes the session and conn data_size fields from the iscsi_transport.
Just pass in the value like with host allocation. This patch also makes
it so the LLD iscsi_conn data is allocated with the iscsi_cls_conn.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:16 -05:00
Mike Christie
a4804cd6eb [SCSI] iscsi: add iscsi host helpers
This finishes the host/session unbinding, by adding some helpers
to add and remove hosts and the session they manage.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:16 -05:00
Mike Christie
756135215e [SCSI] iscsi: remove session and host binding in libiscsi
bnx2i allocates a host per netdevice but will use libiscsi,
so this unbinds the session from the host in that code.

This will also be useful for the iser parent device dma settings
fixes.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:16 -05:00
Mike Christie
32c6e1b9a2 [SCSI] iscsi class: rename iscsi_host to iscsi_cls_host
This renames the iscsi_host to iscsi_cls_host to match the other
structs, because libiscsi wants to use the iscsi_host name in
the future.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:15 -05:00
Mike Christie
d3826721b1 [SCSI] iscsi class, iscsi drivers: remove unused iscsi_transport attrs
max_cmd_len and max_conn are not really used. max_cmd_len is
always 16 and can be set by the LLD. max_conn is always one
since we do not support MCS.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:15 -05:00
Mike Christie
40753caa36 [SCSI] iscsi class, iscsi_tcp/iser: add host arg to session creation
iscsi offload (bnx2i and qla4xx) allocate a scsi host per hba,
so the session creation path needs a shost/host_no argument.
Software iscsi/iser will follow the same behabior as before
where it allcoates a host per session, but in the future iser
will probably look more like bnx2i where the host's parent is
the hardware (rnic for iser and for bnx2i it is the nic), because
it does not use a socket layer like how iscsi_tcp does.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:15 -05:00
Prakash, Sathya
d54d48b80f [SCSI] mpt fusion : Adding FAULT Reset polling work
When the firmware is in Fault state it will be identifed only when the next time
the driver access the IOC state.
This patch includes a polling function in the driver which will be executed in
regular interval to check the status of the firmware and if it is in Fault
state, then the firmware will be reset by the driver.

Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:15 -05:00
Prakash, Sathya
cc4724492d [SCSI] mpt fusion : Setting intial period to 0xFF instead of 0xA
The initial period is set to 0xFF

Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-07-12 08:22:14 -05:00
Prakash, Sathya
cddc0ab711 [SCSI] mpt fusion : Updated copyright statment with 2008 included
Updating copyright statement to include the year 2008

Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:17 -05:00
Prakash, Sathya
22288ca9e6 [SCSI] mpt fusion: Driver version upgrade to 3.04.07
Updating driver version to 3.04.07 from 3.04.06

Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:16 -05:00
Christof Schmitt
aa0fec6239 [SCSI] zfcp: Fix sparse warning by providing new entry in dbf
drivers/s390/scsi/zfcp_dbf.c:692:2: warning: context imbalance in
'zfcp_rec_dbf_event_thread' - different lock contexts for basic block

Replace the parameter indicating if the lock is held with a new entry
function that only acquires the lock. This makes the lock handling
more visible and removes the sparse warning.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:15 -05:00
Martin Peschke
7337891f38 [SCSI] zfcp: remove some __attribute__ ((packed))
There is no need to pack data structures which describe the
contents of records in the new recovery trace.

lcrash currently depends on the binary format for the other traces,
removing the packed attribute from all traces would break trace
debugging with lcrash.

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:15 -05:00
Martin Peschke
70c6654051 [SCSI] zfcp: Refine trace levels of some recovery related events.
This change better spreads trace levels of recovery related events.
There was an overlap of traces for some recovery triggers and the
processing of recovery actions.

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:15 -05:00
Martin Peschke
c3baa9a26c [SCSI] zfcp: Add information about interrupt to trace.
Store the index of the buffer in the inbound queue used to report
request completion in trace record for request coompletion.
This piece of information allows to better compare qdio and zfcp traces.

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:15 -05:00
Martin Peschke
e891bffe92 [SCSI] zfcp: Rename sbal_curr to sbal_last.
sbal_last is more appropriate, because it matches sbal_first.

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:14 -05:00
Martin Peschke
d01d51beee [SCSI] zfcp: Rename sbal_last.
sbal_last is confusing, as it is not the last one actually used,
but just a limit. sbal_limit is a better name.

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:14 -05:00
Martin Peschke
0f83b110f0 [SCSI] zfcp: Remove field sbal_last from trace record.
This field is not needed, because it designates an index with a fix offset
from sbal_first. It's name is confusing anyway.

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:14 -05:00
Christof Schmitt
5c9a6890de [SCSI] zfcp: Remove some sparse warnings
Remove some sparse warnings by telling sparse that zfcp_req_create
acquires the lock for the request queue.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:14 -05:00
Heiko Carstens
b21417820f [SCSI] zfcp: Fix fsf_status_read return code handling
If allocation of a status buffer failed the function incorrectly
returned 0 instead of -ENOMEM.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:13 -05:00
Christof Schmitt
9dfe1cc36b [SCSI] zfcp: Fix mempool pointer for GID_PN request allocation
When allocating memory for GID_PN nameserver requests, the allocation
function stores the pointer to the mempool, but then overwrites the
pointer via memset. Later, the wrong function to free the memory will
be called, since this is based on the stored pointer.

Fix this by first initializing the struct and then storing the pointer.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:13 -05:00
Swen Schillig
d26ab06ede [SCSI] zfcp: receiving an unsolicted status can lead to I/O stall
Processing of an unsolicted status request can lead to a locking race
of the request_queue's queue_lock during the recreation of the
used up status read request while still in interrupt context
of the response handler.

Detaching the 'refill' of the long running status read requests from
the handler to a scheduled work is solving this issue.

In addition, each refill-run is trying to re-establish the full amount
of status read requests, which might have failed in earlier runs.

Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:13 -05:00
Adrian Bunk
1542492122 [SCSI] mpt fusion: make struct mpt_proc_root_dir static
This patch makes the needlessly global struct mpt_proc_root_dir static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: "Prakash, Sathya" <Sathya.Prakash@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:27:12 -05:00
James Bottomley
427e59f09f [SCSI] make use of the residue value
USB sometimes doesn't return an error but instead returns a residue
value indicating part (or all) of the command wasn't completed.  So if
the driver _done() error processing indicates the command was fully
processed, subtract off the residue so that this USB error gets
propagated.

Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:45 -05:00
Alan Stern
19c4158bcd [SCSI] SCSI: remove dev->power.power_state from mesh driver
power.power_state is scheduled for removal.  This patch (as1055)
removes all uses of that field from the SCSI mesh driver.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Paul Mackerras <paulus@au.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:44 -05:00
Harvey Harrison
13a17fdeed [SCSI] aacraid: linit.c make aac_show_serial_number static
drivers/scsi/aacraid/linit.c:865:9: warning: symbol 'aac_show_serial_number' was not declared. Should it be static?

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Mark Salyzyn <Mark_Salyzyn@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:44 -05:00
Mark Salyzyn
a4c38cfa46 [SCSI] aacraid: Add Power Management cards to documentation
Update the documented list of products supported by the aacraid driver.

Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:44 -05:00
Christof Schmitt
3a0d9e9235 [SCSI] zfcp: sysfs attributes for fabric and channel latencies
The latency information is provided on a SCSI device level (LUN)
which can be found at the following location

 /sys/class/scsi_device/<H:C:T:L>/device/cmd_latency
 /sys/class/scsi_device/<H:C:T:L>/device/read_latency
 /sys/class/scsi_device/<H:C:T:L>/device/write_latency

Each sysfs attribute provides the available data: min, max and sum for
fabric and channel latency and the number of requests processed.

An overrun of the variables is neither detected nor treated.  The file
has to be read twice to make a meaningful statement, because only the
differences of the values between the two reads can be used.  A reset
of the values can be achieved by writing to the attribute.

Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:44 -05:00
Christof Schmitt
c9615858a8 [SCSI] zfcp: Track fabric and channel latencies provided by FCP adapter
Add the infrastructure to retrieve the fabric and channel latencies
from FSF commands for each SCSI command that has been processed. For
each unit, the sum, min, max and number of requests is tracked.

Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:42 -05:00
Chandra Seetharaman
688864e298 [SCSI] scsi_dh: Remove hardware handler infrastructure from dm
This patch just removes infrastructure that provided support for hardware
handlers in the dm layer as it is not needed anymore.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:42 -05:00
Chandra Seetharaman
cb520223d7 [SCSI] scsi_dh: Remove hardware handlers from dm
This patch removes the 3 hardware handlers that currently exist
under dm as the functionality is moved to SCSI layer in the earlier
patches.

[jejb: removed more makefile hunks and rejection fixes]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:41 -05:00
Chandra Seetharaman
2651f5d7d3 [SCSI] scsi_dh: Remove dm_pg_init_complete
This patch just removes the dm layer's path initialization completion
routine.  This is separated from the other patch(scsi_dh: Use SCSI
device handler in dm-multipath) Just to make that patch more readable.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:41 -05:00
Chandra Seetharaman
bab7cfc733 [SCSI] scsi_dh: Add a single threaded workqueue for initializing paths
Before this patch set (SCSI hardware handlers), initialization of a
path was done asynchronously. Doing that requires a workqueue in each
device/hardware handler module and leads to unneccessary complication
in the device handler code, making it difficult to read the code and
follow the state diagram.

Moving that workqueue to this level makes the device handler code simpler.
Hence, the workqueue is moved to dm level.

A new workqueue is added instead of adding it to the existing workqueue
(kmpathd) for the following reasons:
	1. Device activation has to happen faster, stacking them along
	   with the other workqueue might lead to unnecessary delay
	   in the activation of the path.
	2. The effect could be felt the other way too. i.e the current
	   events that are handled by the existing workqueue might get
	   a delayed response.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:41 -05:00
Chandra Seetharaman
cfae5c9bb6 [SCSI] scsi_dh: Use SCSI device handler in dm-multipath
This patch converts dm-mpath to use scsi device handlers instead of
dm's hardware handlers.

This patch does not add any new functionality. Old behaviors remain and
userspace tools work as is except that arguments supplied with hardware
handler are ignored.

One behavioral exception is: Activation of a path is synchronous in this
patch, opposed to the older behavior of being asynchronous (changed in
patch 07: scsi_dh: Add a single threaded workqueue for initializing a path)

Note: There is no need to get a reference for the device handler module
(as it was done in the dm hardware handler case) here as the reference
is held when the device was first found. Instead we check and make sure
that support for the specified device is present at table load time.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:41 -05:00
Chandra Seetharaman
5e7dccad36 [SCSI] scsi_dh: add EMC Clariion device handler
This adds support for EMC Clariions. This patch has the features that
currently exists in mainline and advanced features from Ed's patches.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:40 -05:00
Mike Christie
f6dd337ee4 [SCSI] scsi_dh: add hp sw device handler
This patch provides the device handler to support the older hp boxes
which cannot be upgraded.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:40 -05:00
Chandra Seetharaman
fbd7ab3eb5 [SCSI] scsi_dh: add lsi rdac device handler
This patch provides the device handler to support the LSI RDAC SCSI
based storage devices.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:40 -05:00
Chandra Seetharaman
a6a8d9f87e [SCSI] scsi_dh: add infrastructure for SCSI Device Handlers
Some of the storage devices (that can be accessed through multiple paths),
do need some special handling for
	1. Activating the passive path of the storage access.
	2. Decode and handle the special sense codes returned by the devices.
	3. Handle the I/Os being sent to the passive path, especially
           during the device probe time.
when accessed through multiple paths.

As of today this special device handling is done at the dm-multipath
layer using dm-handlers. That works well for (1); for (2) to be handled
at dm layer, scsi sense information need to be exported from SCSI to dm-layer,
which is not very attractive; (3) cannot be done at all at the dm layer.

Device handler has been moved to SCSI mainly to handle (2) and (3) properly.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-06-05 09:23:40 -05:00
Linus Torvalds
53c8ba9540 Linux 2.6.26-rc5 2008-06-04 20:10:44 -07:00