Commit Graph

62 Commits

Author SHA1 Message Date
Peter Oberparleiter b301ea8c81 [S390] cio: allow offline processing for disconnected devices
When disconnected ccw devices are removed, the device has to be set
offline, otherwise there will be side effects including a reference
count imbalance. This patch modifies ccw_device_offline to work for
devices in disconnecte/not operational state. ccw_device_offline is
called by cio for devices which are online during device removal.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-09-09 12:39:07 +02:00
Peter Oberparleiter 91c36919a4 [S390] cio: call ccw driver notify function with lock held
Calling a ccw driver's notify function without the ccw device lock
held opens up a race window between discovery and handling of a change
in the device operational state. As a result, the device driver may
encounter unexpected device malfunction, leading to out-of-retry
situations or similar.

Remove race by extending the ccw device lock from state change
discovery to the calling of the notify function.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-21 19:46:41 +02:00
Sebastian Ott ae437a452e [S390] cio: remove lock from ccw_device_oper_notify.
Remove unnecessary ccw device locking inside ccw_device_oper_notify.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:08 +02:00
Peter Oberparleiter 83262d6349 [S390] cio: provide functions for fcx enabled I/O
Provide functions for assembling and starting fcx enabled I/O request
blocks.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:08 +02:00
Peter Oberparleiter 23d805b647 [S390] cio: introduce fcx enabled scsw format
Extend the scsw data structure to the format required by fcx. Also
provide helper functions for easier access to fields which are present
in both the traditional as well as the modified format.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:07 +02:00
Cornelia Huck c820de39bd [S390] cio: Rework css driver.
Rework the css driver methods to provide sane callbacks for
subchannels of all types.

As a bonus, this cleans up and simplyfies the machine check
handling for I/O subchannels a lot.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:05 +02:00
Michael Ernst 139b83dd57 [S390] cio: Remove cio_msg kernel parameter.
The only sporadically used CIO_DEBUG messages are replaced by ordinary
CIO_MSG_EVENT messages. The CIO_MSG_EVENT messages debug levels are
consolidated.

Signed-off-by: Michael Ernst <mernst@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-05-07 09:23:01 +02:00
Cornelia Huck edf2209692 [S390] cio: Make isc handling more robust.
Introduce an ->isc field in the subchannel to store the desired
interruption subclass, since sch->schib.pmcw.isc may be overwritten
by the hardware on stsch() after machine checks.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:45 +02:00
Peter Oberparleiter 90ab133603 [S390] cio: introduce timed recovery procedure
Add a timed recovery procedure to reactivate ccw devices in cases
where HW/VM events are not sufficient to allow for proper recovery
of reappearing channel paths.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:06 +01:00
Cornelia Huck 46258ab5e4 [S390] cio: Delete timer in ccw_device_verify_done().
Make sure pending timers are always deleted, even if we don't go
through ccw_device_done().

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:04 +01:00
Cornelia Huck db6a64238a [S390] cio: Use dev_{g,s}et_drvdata().
Also define helpers sch_{g,s}et_cdev() to make the intention more
clear.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:02 +01:00
Cornelia Huck b279a4f56d [S390] cio: I/O subchannel specific fields.
Some fields may be !0 only for I/O subchannels. Add some checks
where required. Also adapt cio_enable_subchannel() to make the
caller specify the intparm, which makes it more generic.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:01 +01:00
Cornelia Huck cd6b4f27b9 [S390] cio: Introduce subchannel->private.
Introduce a private pointer in struct subchannel to store
per-subchannel type data (cannot use dev->priv since this
is already used for something else).

Create a new header io_sch.h for I/O subchannel specific structures
and instructions.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:10:59 +01:00
Cornelia Huck bc698bcf88 [S390] cio: Cleanup debug feature usage.
Cleanup cio_debug.h.
Also make CIO_DEBUG add the "cio:" prefix to the printk string
so that it isn't needed for the debug feature.
Fix outdated comments for cio_debug_init() and clean it up.
Enlarge cio_crw to the same size as cio_msg so we may actually
find some relevant information there.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:10:59 +01:00
Cornelia Huck 602b20f2bf [S390] cio: css_driver: Use consistent parameters.
Make all callbacks in css_driver take a struct subchannel (and not
a struct device).

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:10:57 +01:00
Sebastian Ott 14ff56bbb3 [S390] cio: Dump ccw device information in case of timeout.
Information about a ccw device will be dumped in
case of a ccw timeout. This can be enabled with
the kernel parameter ccw_timeout_log.

Signed-off-by: Sebastian Ott <sebott@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:10:55 +01:00
Cornelia Huck c5d4a9997b [S390] cio: Register/unregister subchannels only from kslowcrw.
Make sure all subchannel handling is done on the slow path workqueue
so that we don't have races between an old subchannel unregistering
and a new subchannel with the same name registering.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 11:13:49 +01:00
Cornelia Huck 3f4cf6e72f [S390] cio: Avoid machine check vs. not operational races.
There was the possibilty that an action like ccw_device_set_offline()
triggered by a device gone machine check might trigger a not oper
event. Unfortunately, this could lead to the situation that we tried
to unregister a subchannel twice: Once from the slow path evaluation,
and once via the not oper event.

Fix this by always using the same mechanism (css_schedule_eval()) for
triggering the unregister. This makes sure that unregistration will
only be done once. As an added bonus, it also simplyfies the code.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-12 16:13:02 +02:00
Cornelia Huck 7c9f4e3aaa [S390] cio: rename css to channel_subsystems
Rename css[] to channel_subsystems[] to avoid name clashes.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-10-12 16:12:58 +02:00
Cornelia Huck e556bbbd9d [S390] cio: Clean up messages.
- Remove unneeded messages.
- Move some messages into the debug feature.
- Use dev_* where appropriate.
- Use "cio: " prefix consistently.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-07-27 12:29:19 +02:00
Peter Oberparleiter 3ecb0a5a7b [S390] cio: deregister ccw device when pgid disband failed
Deregister ccw device when device failure is detected during offline-
processing (e.g. when no last-path-gone indication was presented by
the hardware) to prevent the device from entering a non-recoverable
not-operational state.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-05-31 17:38:14 +02:00
Cornelia Huck 82b7ac058f [S390] cio: Dont call css_update_ssd_info from interrupt context.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-04-27 16:01:41 +02:00
Peter Oberparleiter 7ad6a24970 [S390] cio: fix subchannel channel-path data usage
Ensure that channel-path related subchannel data is only retrieved and
used when it is valid and that it is updated when it may have changed.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-04-27 16:01:40 +02:00
Peter Oberparleiter 83b3370c79 [S390] cio: replace subchannel evaluation queue with bitmap
Use a bitmap for indicating which subchannels require evaluation
instead of allocating memory for each evaluation request. This
approach reduces memory consumption during recovery in case of
massive evaluation request occurrence and removes the need for
memory allocation failure handling.

Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-04-27 16:01:40 +02:00
Peter Oberparleiter e5854a5839 [S390] cio: Channel-path configure function.
Add a new attribute to the channel-path sysfs directory through which
channel-path configure operations can be triggered. Also listen for
hardware events requesting channel-path configure operations and
process them accordingly.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-04-27 16:01:39 +02:00
Peter Oberparleiter e6b6e10ac1 [S390] cio: Introduce separate files for channel-path related code.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-04-27 16:01:38 +02:00
Peter Oberparleiter f86635fad1 [S390] cio: Introduce struct chp_id.
Introduce data type for channel-path IDs.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-04-27 16:01:38 +02:00
Cornelia Huck 2470b648e1 [S390] cio: Call cancel_halt_clear even when actl == 0.
The subchannel may just be status pending, even with actl == 0. We
must go through the cancel_halt_clear procedure to put the subchannel
into a defined state.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-03-05 23:36:02 +01:00
Cornelia Huck 7c8427c3fa [S390] cio: Use path verification to check for path state.
After I/O has been killed by the common I/O layer, trigger path
verification which will queue cio_device_nopath_notify itself if it
finds a device to be without paths.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-03-05 23:35:59 +01:00
Cornelia Huck ee04bbccde [S390] cio: Fix locking when calling notify function.
Make sure we hold the device lock when we modify the ccw device
structure but always call the notify function without the lock held.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-03-05 23:35:56 +01:00
Heiko Carstens 4d284cac76 [S390] Avoid excessive inlining.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:18:53 +01:00
Cornelia Huck 18374d376c [S390] cio: Restart path verification after unsolicited interrupt.
If we try to start path verification when an unsolicited interrupt
is already pending, stctl shows status pending and we delay path
verification again. We need to check for the doverify bit when the
unsolicited interrupt comes in and then do path verification.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:17:09 +01:00
Heiko Carstens 2b67fc4606 [S390] Get rid of a lot of sparse warnings.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:16:47 +01:00
Cornelia Huck d7b5a4c94f [S390] Support for disconnected devices reappearing on another subchannel.
- create a 'pseudo_subchannel' per channel subsystem (the 'orphanage')
- use the orphanage as a shelter for ccw_devices that can't remain on the same
  subchannel

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-08 15:54:28 +01:00
Cornelia Huck 7674da77cb [S390] Some preparations for the dynamic subchannel mapping patch.
- Move adding subchannel attributes to css_register_subchannel().
- Don't call device_trigger_reprobe() for non-operational devices.
- Introduce io_subchannel_create_ccwdev().

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-08 15:54:21 +01:00
Martin Schwidefsky c16375329c [S390] more workqueue fixes.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-08 15:53:57 +01:00
Cornelia Huck d23861ff1a [S390] cio: Retry internal operations after vary off.
If I/O was running on a just varied off chpid, it will be terminated.
If this was a common I/O layer internal I/O, it needs to be retried.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04 15:41:04 +01:00
Cornelia Huck 24cb5b4846 [S390] cio: Use path verification for last path gone after vary off.
If the last path to a device is gone after a chpid has been varied
off, putting it on the slow queue doesn't prevent a device driver
from still attempting to use it (it may stay on the slow queue for a
long time). Instead, trigger a verify event which will prevent I/O
attempts from the device driver immediately.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04 15:41:01 +01:00
Peter Oberparleiter 8b42f5c202 [S390] cio: invalid device operational notification
Reset device operational notification flag when channel paths become
unavailable during path verification.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-18 18:30:43 +02:00
Cornelia Huck 12975aef62 [S390] cio: remove casts from/to (void *).
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-11 15:31:47 +02:00
Cornelia Huck e7769b48a0 [S390] cio: Remove grace period for vary off chpid.
The grace period handling introduced needless complexity. It didn't
help the dasd driver (which can handle terminated I/O just well),
and it doesn't help for long running channel programs (which won't
complete during the grace period anyway). Terminating I/O using a
path that just disappeared immediately is much more consistent with
what the user expects.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-11 15:31:41 +02:00
Cornelia Huck 7896426805 [S390] cio: Use ccw_dev_id and subchannel_id in ccw_device_private
Use the proper structures to identify device and subchannel. Change
get_disc_ccwdev_by_devno() to get_disc_ccwdev_by_dev_id().

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-11 15:31:38 +02:00
Cornelia Huck 08983787d2 [S390] cio: add missing KERN_INFO printk header.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-11 15:31:30 +02:00
Cornelia Huck f1ee3281be [S390] Add timeouts during sense PGID, path verification and disband PGID.
While the machine owns us an interrupt in these cases (and we should get
one), reality isn't always like that...

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-04 20:02:02 +02:00
Peter Oberparleiter 28bdc6f623 [S390] cio: always query all paths on path verification.
Reappearing channel paths are sometimes not utilized by CCW devices
because path verification incorrectly relies on path-operational-mask
information which is not updated until a channel path has been used
again.
Modify path verification procedure to always query all available paths
to a device.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20 15:59:59 +02:00
Heiko Carstens 81388d2a45 [S390] Missing initialization in common i/o layer.
Previous patch that was intended to reduce stack usage within common
i/o layer didn't consider implicit memset(..., 0, ...) used with the
initializations used before.
Add these missing memsets wherever it's not obvious that the
concerned memory region is zeroed. This should give the same semantics
as before.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20 15:59:17 +02:00
Heiko Carstens 292888c81e [S390] cio: kernel stack overflow.
Use different kind of assignment to make sure gcc doesn't create code
that creates temp variables on the stack, assigns values to it and
copies the content of the whole temp variable to the destination.
This reduces stack usage of e.g. ccwgroup_driver_register from 976
to 48 bytes instead.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-08-30 14:33:35 +02:00
Peter Oberparleiter 65200c291c [S390] lost interrupt after chpid vary off/on cycle.
I/O on a CCW device may stall if a channel path to that device is
logicaly varied off/on. A user I/O interrupt can get misinterpreted
as interrupt for an internal path verification operation due to a
missing check and is therefore never reported to the device driver.

Correct check for pending interruptions before starting path
verification.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-08-07 17:00:33 +02:00
Peter Oberparleiter ba4ba8a69d [S390] permanent subchannel busy conditions may cause I/O stall
In special conditions where a subchannel rejects the HALT I/O-
instruction with a busy indication (cc 2), I/O may stall.
I/O request termination logic retries HALT I/O indefinitely
because it expects HALT I/O to alter the subchannel status which
is not true when cc 2 is returned.
In case of a busy indication, try CLEAR I/O instruction immediately.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-07-27 14:00:23 +02:00
Cornelia Huck 7e560814de [S390] path grouping and path verifications fixes.
1. Multipath devices for which SetPGID is not supported are not handled well.
   Use NOP ccws for path verification (sans path grouping) when SetPGID is not
   supported.
2. Check for PGIDs already set with SensePGID on _all_ paths (not just the
   first one) and try to find a common one. Moan if no common PGID can be
   found (and use NOP verification). If no PGIDs have been set, use the css
   global PGID (as before). (Rationale: SetPGID will get a command reject if
   the PGID it tries to set does not match the already set PGID.)
3. Immediately before reboot, issue RESET CHANNEL PATH (rcp) on all chpids. This
   will remove the old PGIDs. rcp will generate solicited CRWs which can be
   savely ignored by the machine check handler (all other actions create
   unsolicited CRWs).

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-07-12 16:40:19 +02:00