1781 Commits

Author SHA1 Message Date
Stefan Weinhuber
22825ab769 [S390] dasd: support DIAG access for read-only devices
When a DASD device is used with the DIAG discipline, the DIAG
initialization will indicate success or error with a respective
return code. So far we have interpreted a return code of 4 as error,
but it actually means that the initialization was successful, but
the device is read-only. To allow read-only devices to be used with
DIAG we need to accept a return code of 4 as success.

Re-initialization of the DIAG access is also part of the DIAG error
recovery. If we find that the access mode of a device has been
changed from writable to read-only while the device was in use,
we print an error message.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:34 +01:00
Sebastian Ott
d40f7b75a2 [S390] cio: dont unregister a busy device in ccw_device_set_offline
If we detect a busy subchannel after the driver's set_offline
callback returned in ccw_device_set_offline, the current behavior
is to unregister the device, which may lead to undesired
consequences. Change this to just quiesce the subchannel and go on
with the offline processing.

Note: This is no excuse for not fixing these drivers -
after the set_offline callback they should have no running IO!

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:33 +01:00
Peter Oberparleiter
de1b04388f [S390] cio: improve error recovery for internal I/Os
Improve error recovery for internal I/Os by repeating each I/O
256 times per path to cope with long-running non-permanent error
conditions. Also retry each path twice to cope with link flapping,
i.e. single paths becoming unavailable in the order in which they
are tried.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:33 +01:00
Sebastian Ott
7a8ad1001c [S390] cio: change locking in io_subchannel_remove
IO subchannels are always unregistered in process context, so use
spin_lock_irq in the corresponding remove callback.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:33 +01:00
Sebastian Ott
6e9a0f67de [S390] cio: quiesce subchannel in io_subchannel_remove
Ensure that there will be no more interrupts for an
unregistered device by using the same quiesce and disable loop
as in io_subchannel_shutdown.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:32 +01:00
Sebastian Ott
0c609fca24 [S390] cio: handle busy subchannel in ccw_device_move_to_sch
Try to disable the old subchannel before we ask the driver core
to move the attached device to a new parent. This way we can use
the QUIESCE state during shutdown which prevents a possible use
after free situation in some error cases.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:32 +01:00
Sebastian Ott
ec64333c3a [S390] cio: handle failed disable_subchannel after device recognition
Handle a failing cio_disable_subchannel at the end of our device
recognition as if the recognition itself failed. This way
subsequent registration steps do not need to handle enabled
subchannels.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:32 +01:00
Sebastian Ott
56e6b796fe [S390] cio: fix quiesce state
DEV_STATE_QUIESCE is used to stop all IO on a busy subchannel.
This patch fixes the following problems related to the QUIESCE
state:

* Fix a potential race condition which could occur when the
resulting state was DEV_STATE_OFFLINE.

* Add missing locking around cio_disable_subchannel,
ccw_device_cancel_halt_clear and the cdev's handler.

* Loop until we know for sure that the subchannel is disabled.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:32 +01:00
Sebastian Ott
24a1872d64 [S390] cio: add per device initialization status flag
The function ccw_device_unregister has to ensure to remove
all references obtained by device_add and device_initialize.
Unfortunately it gets called for devices which are
1) uninitialized, 2) initialized but unregistered, and
3) registered devices. To distinguish 1) and 2) this patch
introduces a new flag "initialized", which is 1 as long as we
hold the initial device reference.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:32 +01:00
Sebastian Ott
7d253b9a1a [S390] cio: remove registered flag from ccw_device_private
We used to maintain a "registered" flag in our ccw_device_private
structure. This patch removes the "registered" flag and converts
all users of it to device_is_registered which has the exact same
meaning.

Note: The usage the atomic operation test_and_clear_bit is replaced
by the non-atomic if (device_is_registered()) device_del(). This
will not do harm, since we serialize calls to ccw_device_unregister
with a single-threaded workqueue.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:32 +01:00
Peter Oberparleiter
d7d12ef2be [S390] cio: make steal lock procedure more robust
An Unconditional Reserve + Release operation (steal lock) for a
boxed device may fail when encountering special error cases
(e.g. unit checks or path errors). Fix this by using the more
robust ccw_request infrastructure for performing the steal lock
CCW program.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:32 +01:00
Peter Oberparleiter
52ef0608e3 [S390] cio: use sense-pgid operation for path verification
Set-pgid operations fail for some device types under z/VM for which
the hypervisor has already set the pgid. Also reserved devices or
changed pgids are not correctly recognized. Fix these problems by
using a combination of sense-pgid and set-pgid and by also accepting
pre-defined pgid settings.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:31 +01:00
Peter Oberparleiter
454e1fa1eb [S390] cio: split PGID settings and status
Split setting (driver wants feature enabled) and status (feature
setup was successful) for PGID related ccw device features so that
setup errors can be detected. Previously, incorrectly handled setup
errors could in rare cases lead to erratic I/O behavior and
permanently unusuable devices.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:31 +01:00
Peter Oberparleiter
4257aaecff [S390] cio: remove intretry flag
After changing all internal I/O functions to use the newly introduced
ccw request infrastructure, retries are handled automatically after a
clear operation. Therefore remove the internal retry flag and
associated code.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:31 +01:00
Peter Oberparleiter
350e91207b [S390] cio: allow setting not-operational devices offline
Accept a request for setting a not-operational device offline.
This way, users can remove devices from Linux which would otherwise
remain unusable until reboot.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:31 +01:00
Peter Oberparleiter
9679baaf85 [S390] cio: use ccw request infrastructure for pgid
Use the newly introduced ccw request infrastructure to implement
pgid related operations: sense pgid, set pgid and disband pg.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:31 +01:00
Peter Oberparleiter
39f5360b3d [S390] cio: use ccw request infrastructure for sense id
Use the newly introduced ccw request infrastructure to implement
the sense id operation.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:31 +01:00
Peter Oberparleiter
e1f0fbd655 [S390] cio: consistent infrastructure for internal I/O requests
Reduce code duplication by introducing a central infrastructure to
perform an internal I/O operation on a CCW device.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:31 +01:00
Peter Oberparleiter
16b9a0571d [S390] cio: dont panic in non-fatal conditions
Remove the call to BUG() for situations which are unexpected
but do not cause actual problems.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:30 +01:00
Peter Oberparleiter
1f5bd3848b [S390] cio: ensure proper locking during device recognition
Device recognition needs to be started with the ccw device lock
held to prevent race conditions between I/O starting and interrupt
reception.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:30 +01:00
Peter Oberparleiter
7c4d964fa4 [S390] cio: handle error during path verification consistently
Handle verification errors consistently through the existing
callback ccw_device_done to reduce cleanup code duplication.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:30 +01:00
Peter Oberparleiter
736b5db895 [S390] cio: handle error during device recognition consistently
Remove the return code from ccw_device_recognition and handle
recognition errors through the existing callback
ccw_device_recog_done to reduce cleanup code duplication.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:30 +01:00
Peter Oberparleiter
a7ae2c02f5 [S390] cio: inform user when online/offline processing fails
Print a warning message in case a ccw device enters boxed or
not operational state during online/offline processing.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:30 +01:00
Peter Oberparleiter
37de53bb52 [S390] cio: introduce ccw device todos
Introduce a central mechanism for performing delayed ccw device work
to ensure that different types of work do not overwrite each other.
Prioritization ensures that the most important work is always
performed while less important tasks are either obsoleted or repeated
later.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:30 +01:00
Peter Oberparleiter
390935acac [S390] cio: introduce subchannel todos
Ensure that current and future users of sch->work do not overwrite
each other by introducing a single mechanism for delayed subchannel
work.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:30 +01:00
Peter Oberparleiter
5d6e6b6f6f [S390] cio: introduce parent-initiated device move
Change the initiative to update subchannel-ccw device associations
to the subchannel: when there is an indication that the internal
association no longer reflects the current hardware state, mark
each affected subchannel as requiring attention. Once processing
reaches a subchannel, determine the correct association for that
subchannel at that time and perform the necessary device_move
operations.

This change fixes problems with the previous approach which would
leave devices in an inconsistent state when a new hardware change
occurred while a device_move was already scheduled.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:29 +01:00
Peter Oberparleiter
60e4dac1ab [S390] cio: fix repeat setting of cdev parent association
sch_create_and_recog_new_device() associates a parent subchannel
with its ccw device child even though this is already done by
the subsequently called io_subchannel_recog(). Also make sure
io_subchannel_recog() sets the association under lock.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:29 +01:00
Peter Oberparleiter
48e4c385c5 [S390] cio: fix double free in case of probe failure
io_subchannel_probe() frees memory for sch->private which is later
freed again when io_subchannel_remove() is called. Fix this problem
by removing the cleanup in io_subchannel_probe().

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07 12:51:29 +01:00
Adam Buchbinder
6070d81eb5 tree-wide: fix misspelling of "definition" in comments
"Definition" is misspelled "defintion" in several comments; this
patch fixes them. No code changes.

Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-04 23:41:47 +01:00
Christof Schmitt
54987386ee [SCSI] zfcp: Remove flag ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP
The flag ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP is never set and hence can
be removed. This is a leftover from the time when zfcp had to decide
whether the target supports a "logical unit reset" or not. Nowadays,
the SCSI midlayer calls the eh_device_reset_handler or the
eh_target_reset_handler and zfcp simply maps this to a "logical unit
reset" or a "target reset".

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:18 -06:00
Christof Schmitt
0fdd21330a [SCSI] zfcp: Activate fc4s attributes for zfcp in FC transport class
Enable the display of supported and active fc4s for zfcp in the FC
transport class. zfcp only supports FCP, so simply hard-code this
information.  The zfcp hbaapi already has this information hardcoded,
but this would allow to switch from the coding in the zfcp hbaapi to
the common FC transport attributes in the future.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:18 -06:00
Christof Schmitt
af4de36d91 [SCSI] zfcp: Block scsi_eh thread for rport state BLOCKED
In case the SCSI error recovery starts because of a SCSI command
timeout, but then something else triggers the rport to be deleted, the
SCSI error recovery will run to the end and set the SCSI device
offline. To prevent this, call the FC transport function
fc_block_scsi_eh which waits until the rport leaves the BLOCKED state.
This guarantees that communication is possible if the rport is ONLINE,
or the SCSI devices will be removed if the rport state switches to
NOT_PRESENT.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:17 -06:00
Christof Schmitt
4c571c659e [SCSI] zfcp: Update FSF error reporting
The SCSI midlayer retries commands based on the remote port state and
the command status reported by the driver. Returning
DID_TRANSPORT_DISRUPTED is a better approach, use this for reporting
FSF errors back to the SCSI midlayer.  See
http://marc.info/?l=linux-scsi&m=125668044215051&w=2 as reference.

There is also no need in special treatment of ABORTED commands, so
remove the ZFCP_STATUS_FSFREQ_ABORTED, the commands are then returned
with DID_TRANSPORT_DISRUPTED.

Also remove the ZFCP_STATUS_FSFREQ_RETRY: It is useless, no retry is
happening in the FSF layer and nobody checks the state of this flag.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:16 -06:00
Christof Schmitt
ee744622c6 [SCSI] zfcp: Improve ELS ADISC handling
Introduce kmem_cache for ELS ADISC data to guarantee the required
hardware alignment and free the allocated memory in case the send
failes.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:16 -06:00
Christof Schmitt
7c7dc19681 [SCSI] zfcp: Simplify handling of ct and els requests
Remove some redundancies in FC related code and trace:
- drop redundant data from SAN trace (local s_id that only changes
  during link down, ls_code that is already part of payload, d_id in
  ct response trace that is always the same as in ct request trace)
- use one common fsf struct to hold zfcp data for ct and els requests
- leverage common fsf struct for FC passthrough job data, allocate it
  with dd_bsg_data for passthrough requests and unify common code for
  ct and els passthrough request
- simplify callback handling in zfcp_fc

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:15 -06:00
Christof Schmitt
800c0cad96 [SCSI] zfcp: Remove ZFCP_DID_MASK
Instead of assigning 4 bytes with the highest byte masked out, use a 3
byte array with the ntoh24 and h24ton helper functions, thus
eliminating the need for the ZFCP_DID_MASK.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:14 -06:00
Christof Schmitt
bd0072ecc4 [SCSI] zfcp: Move WKA port to zfcp FC code
The well-known-address (WKA) port handling code is part of the FC code
in zfcp. Move everything WKA related to the zfcp_fc files and use the
common zfcp_fc prefix for structs and functions. Drop the unused key
management service while renaming the struct, no request could ever
reach this service in zfcp and it is obsolete anyway.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:14 -06:00
Christof Schmitt
dbf5dfe9db [SCSI] zfcp: Use common code definitions for FC CT structs
Use common code definitions for FC GPN_FT and GID_PN
instead of inventing private ones. Move the private structs still
required inside zfcp to zfcp_fc header file.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:13 -06:00
Christof Schmitt
9d05ce2c0a [SCSI] zfcp: Use common code definitions for FC ELS structs
Use common code definitions for FC plogi, logo, rscn and adisc structs
instead of inventing private ones. Move the private struct for issuing
ELS ADISC inside zfcp to zfcp_fc header file.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:11 -06:00
Christof Schmitt
4318e08c84 [SCSI] zfcp: Update FCP protocol related code
Use common data structures for FCP CMND, FCP RSP and related
definitions and remove zfcp private definitions. Split the FCP CMND
setup and FCP RSP evaluation code in seperate functions. Use inline
functions to not negatively impact the I/O path.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:10 -06:00
Christof Schmitt
8830271c48 [SCSI] zfcp: Dont fail SCSI commands when transitioning to blocked fc_rport
If an error occurs that triggers the call to fc_remote_port_delete,
ideally this call would happen before any I/O is passed back to the
SCSI midlayer through scsi_done. The SCSI midlayer will retry the
commands and fc_remote_port_chkready will return the correct status
code.  But with the delay between calling scsi_done in softirq context
and the call to fc_remote_port_delete from the workqueue, there is a
window where zfcp returns DID_ERROR. This leads to SCSI error recovery
which then leads to offline SCSI devices since all recovery actions
will fail with the rport now being blocked.

In this window, zfcp has to return DID_IMM_RETRY just as the FC
transport class would do in fc_remote_port_chkready for the blocked
fc_rport. As soon as the fc_rport is BLOCKED, fc_remote_port_chkready
will do the right thing.

Additionally, there are two more cases to catch in zfcp_scsi_queuecommand:
- After the port has been opened, the unit has to be opened. During
  this period I/O has to be retried. This can also be handled with
  DID_IMM_RETRY.
- If the access to the unit fails, but the port is good, then
  this single unit cannot be accessed and I/O to this unit has to fail
  without involving the FC transport class.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:09 -06:00
Swen Schillig
9eae07ef6b [SCSI] zfcp: Assign scheduled work to driver queue
The port_scan work was scheduled to the work_queue provided by the
kernel. This resulted on SMP systems to a likely situation that more
than one scan_work were processed in parallel. This is not required
and openes the possibility of race conditions between the removal of
invalid ports and the enqueue of just scanned ports.  This patch
synchronizes the scan_work tasks by scheduling them to adapter local
work_queue.

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@suse.de>
2009-12-04 12:02:08 -06:00
Swen Schillig
6b183334c2 [SCSI] zfcp: Remove STATUS_COMMON_REMOVE flag as it is not required anymore
The flag ZFCP_STATUS_COMMON_REMOVE was used to indicate that a
resource is not ready to be used or about to be removed from the
system. This is now better done by an improved list handling
and therefore the additional indicator is not required anymore.

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@suse.de>
2009-12-04 12:02:07 -06:00
Christof Schmitt
c1fad41764 [SCSI] zfcp: Implement module unloading
With the reference counting for zfcp data structures, it is now
possible to implement module unloading again. Module unloading
requires to free all data structures in the module exit function. This
is done by unregistering zfcp from s390 cio and the SCSI midlayer
first in the module exit function.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:06 -06:00
Christof Schmitt
d9742b42b5 [SCSI] zfcp: Merge trace code for fsf requests in one function
The latencies traced per fsf request are traced for sysfs output and
for blktrace, each in one function. Simplify the tracing code by
merging both tracing functions into one.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:05 -06:00
Christof Schmitt
25458eb791 [SCSI] zfcp: Access ports and units with container_of in sysfs code
When accessing port and unit attributes, use container_of instead of
dev_get_drvdata. This eliminates some code checker warnings about
aliased access of data structures.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:02:04 -06:00
Swen Schillig
b42aeceb35 [SCSI] zfcp: Remove suspend callback
The callback for suspend is not required because it contains exactly
the same functionality as the _set_offline routine does.

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@suse.de>
2009-12-04 12:02:03 -06:00
Swen Schillig
de3dc57214 [SCSI] zfcp: Remove global config_mutex
The global config_mutex was required for the serialization of a
configuration change within the zfcp driver.  This global locking is
now obsolete and can be removed.  The requirement of serializing the
access to a zfcp_adapter reference via a ccw_device is realized wth a
static spinlock.

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@suse.de>
2009-12-04 12:02:02 -06:00
Swen Schillig
f3450c7b91 [SCSI] zfcp: Replace local reference counting with common kref
Replace the local reference counting by already available mechanisms
offered by kref. Where possible existing device structures were used,
including the same functionality.

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@suse.de>
2009-12-04 12:02:02 -06:00
Swen Schillig
ecf0c7721b [SCSI] zfcp: Replace global config_lock with local list locks
The global config_lock was used to protect the configuration organized
in independent lists. It is not necessary to have a lock on driver
level for this purpose.  This patch replaces the global config_lock
with a set of local list locks.

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@suse.de>
2009-12-04 12:02:01 -06:00