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path: root/drivers/s390/cio/device.c
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2010-11-10[S390] cio: fix incorrect ccw_device_init_countSebastian Ott1-1/+10
If device recognition is interrupted by a subchannel event indicating that the device is gone, ccw_device_init_count is not correctly decreased. Fix this by reporting the corresponding event to the device recognition callback via the state machine. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25[S390] cio: fix I/O cancel functionPeter Oberparleiter1-0/+1
Function ccw_device_cancel_halt_clear may cause an unexpected kernel panic if a clear function is currently active at the subchannel for which it is called. In that case, the iretry counter used to determine the number of retries is never initialized, leading to an immediate failure of the function which results in a kernel panic. Fix this by initializing the iretry counter when the function is first called. Also replace the kernel panic with a return code: a single malfunctioning I/O device should not automatically cause a system-wide kernel panic. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25[S390] cio: notify drivers of channel path eventsSebastian Ott1-0/+9
This patch adds a notification mechanism to inform ccw drivers about changes to channel paths, which occured while the device is online. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25[S390] cio: fix memleak in resume pathSebastian Ott1-2/+6
If a ccwdevice is lost during hibernation and a different ccwdevice is attached to the same subchannel, we will deregister the old ccw device and register the new one. Since deregistration is not allowed in this context, we handle this action later. However, some parts of the registration process for the new device were started anyway, so that the old device structure is no longer accessible. Fix this by deferring both actions to the afterwards scheduled subchannel event. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-08-09[S390] cio: ccw_device_online_store return -EINVAL in case of missing driverSebastian Ott1-4/+6
If no driver is attached to a device or the driver provides no set_online/set_offline function, setting this device online/offline via its sysfs online attribute will silently fail but return success. This patch changes the behavior to return -EINVAL in those cases. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-08-09[S390] cio: CHSC SIOSL SupportMichael Ernst1-0/+37
A Linux interface for the CHSC command store-I/O-operation-status-and-initiate-logging (SIOSL). Model-dependent logging within the channel subsystem can be invoked via a helper function or a writable subchannel device attribute. Signed-off-by: Michael Ernst <mernst@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-03-08[S390] cio: fix init_count in case of recognition after steal lockSebastian Ott1-2/+3
After we try to steal a lock on a ccw device in boxed state, we have to restart device recognition and potentially reprobing. In this case ccw_device_init_count was erroneously decreased twice. This patch fixes the issue. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-27[S390] cio: trigger subchannel event at resume timeSebastian Ott1-50/+61
ccw_device_pm_restore: trigger subchannel event to better handle changes to the subchannel device. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-27[S390] ccw_device_notify: improve return codesSebastian Ott1-5/+5
Callers of ccw_device_notify could not distinguish between a driver who has no notifier registered and a driver who doesn't want to keep a device after a certain event. Change this by adding proper return codes. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-27[S390] cio: make wait_events interruptibleSebastian Ott1-3/+8
Make the potentially long blocking wait_event's used by the cio settle mechanism interruptible. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-27[S390] cio: consolidate workqueuesSebastian Ott1-22/+6
We used to maintain 2 singlethreaded workqueues for synchronization and to trigger work from interrupt context. Since our latest cio changes we only use one of these workqueues. So get rid of the unused workqueue, rename the remaining one to "cio_work_q" and move its ownership to the channel subsystem driver. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-18[S390] cio: fix drvdata usage for the console subchannelSebastian Ott1-0/+1
Using dev_set_drvdata prior to device_register will force the driver core to kmalloc its private data. Since we use this for the console subchannel lets set the drvdata before taking the subchannels spinlock. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-15const: constify remaining dev_pm_opsAlexey Dobriyan1-1/+1
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-07[S390] cio: dont unregister a busy device in ccw_device_set_offlineSebastian Ott1-9/+20
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[S390] cio: change locking in io_subchannel_removeSebastian Ott1-3/+2
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[S390] cio: quiesce subchannel in io_subchannel_removeSebastian Ott1-1/+9
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[S390] cio: handle busy subchannel in ccw_device_move_to_schSebastian Ott1-2/+22
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[S390] cio: fix quiesce stateSebastian Ott1-16/+19
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[S390] cio: add per device initialization status flagSebastian Ott1-0/+6
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[S390] cio: remove registered flag from ccw_device_privateSebastian Ott1-8/+3
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[S390] cio: remove intretry flagPeter Oberparleiter1-41/+17
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[S390] cio: allow setting not-operational devices offlinePeter Oberparleiter1-5/+4
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[S390] cio: use ccw request infrastructure for pgidPeter Oberparleiter1-3/+0
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[S390] cio: ensure proper locking during device recognitionPeter Oberparleiter1-0/+2
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[S390] cio: handle error during device recognition consistentlyPeter Oberparleiter1-49/+8
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[S390] cio: inform user when online/offline processing failsPeter Oberparleiter1-0/+22
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[S390] cio: introduce ccw device todosPeter Oberparleiter1-103/+100
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[S390] cio: introduce subchannel todosPeter Oberparleiter1-18/+5
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[S390] cio: introduce parent-initiated device movePeter Oberparleiter1-331/+182
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[S390] cio: fix repeat setting of cdev parent associationPeter Oberparleiter1-4/+1
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[S390] cio: fix double free in case of probe failurePeter Oberparleiter1-6/+5
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>
2009-10-14[S390] cio: change misleading console logicPeter Oberparleiter1-5/+4
Use cio_is_console() in io_subchannel_probe to indicate that the special handling is console specific. As long as there is no other subchannel for which this might be true, it is misleading to speak of "early devices". Should more of these devices be introduced, a cleanup of all console special handling is in order anyway. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-10-06[S390] cio: make not operational handling consistentPeter Oberparleiter1-2/+2
When a ccw device appears not operational, inform the associated device driver and act according to the response: if the driver wants to keep the device, put it into the disconnected state. If not, or if there is no driver or if the device is not online, unregister it. This approach is consistent with no-path event handling. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-23[S390] cio: introduce css_settleSebastian Ott1-6/+12
Introduce the css_driver callback settle which can be implemented by a subchannel driver to wait for the subchannel type specific asynchronous work to finish. In channel_subsystem_init_sync we call that for each subchannel driver. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-23[S390] cio: merge init callsSebastian Ott1-17/+3
Define initialization sequence of css and ccw bus init calls by merging them into a single init call. Also introduce channel_subsystem_init_sync to wait for the initialization of devices to finish. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-15driver model: constify attribute groupsDavid Brownell1-1/+1
Let attribute group vectors be declared "const". We'd like to let most attribute metadata live in read-only sections... this is a start. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-11[S390] cio: remove ccw_device init_nameSebastian Ott1-17/+6
We used the init_name to set the console ccw_device's name early at the boot stage. This patch moves the name setting (for all ccw devices) to the point where we actually register the device. At this time we can do dynamic allocations and therefore use dev_set_name. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: move final put_device to ccw_device_unregisterSebastian Ott1-3/+4
We use a test_and_clear_bit to prevent a device from being unregistered twice. Unfortunately in this cases the "final" put_device (from device_initialize) was issued more than once, resulting in an use after free error. Fix this by moving this put_device to ccw_device_unregister. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: fix use after free in s390 debug featureSebastian Ott1-5/+9
When using s390dbf with "%s" in sprintf format strings the string itself is not copied to the dbf buffer. Since in this case only pointers are stored in the s390dbf, we should not use dev_name - which is bound to the lifetime of the device. Reading this entry from s390dbf after the device was released will cause an use after free error. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: failing set online/offline processing.Michael Ernst1-35/+65
When unit checks trigger sensing the device state is set to W4SENSE until sense completion; then the device state is set back to ONLINE. If a unit check occurs while set online or set offline requests are processed then it might happen that the device's temporary W4SENSE state causes these functions to terminate, leaving the device in an inconsistent state when the state is set back to ONLINE later on so that the device cannot be set online or offline any longer. To solve this, set online/offline and related rollback or error routines are processed only if the device is in a final or DISCONNECTED state. Signed-off-by: Michael Ernst <mernst@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: ensure to hold a reference for deferred deregistrationSebastian Ott1-8/+6
Ensure to always hold an extra device reference for scheduling a subchannel deregistration, by moving the get_device to ccw_device_schedule_sch_unregister. This fixes an use after free error in ccw_device_call_sch_unregister where put_device was called on an already freed device structure. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: increase trace levelSebastian Ott1-2/+2
Move debug traces for start I/O and interrupt events to exclusive trace levels. Also change tracing in hot-path from sprintf (costly) to hex. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] cio: consolidate subchannel intparm resetPeter Oberparleiter1-10/+0
Ensure that the hardware interruption parameter for a subchannel is reset when the associated subchannel data structure is freed. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-08-23[S390] cio: fix double free after failed device initializationSebastian Ott1-3/+1
If io_subchannel_initialize_dev fails it will release the only reference to the ccw device therefore the caller should not kfree this device since this is done in the release function. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-16[S390] cio: force console functionMartin Schwidefsky1-0/+9
If something goes wrong in a suspend / resume cycle a ccw based console if very likely in the suspended state and cannot print anything. Introduce ccw_device_force_console to force the wake up of the console device to be able to print the oops message. The console device drivers should use this function only if the system paniced. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-16[S390] pm: io subchannel driver power management callbacksCornelia Huck1-0/+14
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-16[S390] pm: ccw bus power management callbacksSebastian Ott1-0/+237
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-31[S390] cio: online_store - trigger recognition for boxed devicesSebastian Ott1-1/+1
Start a new device recognition if someone writes to sysfs online attribute of a boxed ccw device. The current test will fail, since cu_type != 0 for devices which were recognized before. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-31[S390] cio: disallow online setting of device in transient stateSebastian Ott1-1/+5
Return -EAGAIN on writes to sysfs online attribute if the corresponding ccw device is in transient state. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-31[S390] cio: introduce notifier for boxed stateSebastian Ott1-2/+2
If a ccw device did not respond in time during internal io, we set it into boxed state. With this patch we have the following behaviour: * the ccw driver will get a notification if the device was online and goes into the boxed state * if the device was disconnected and got boxed nothing special is to be done (it will be handled in reprobing later) * if the device got boxed while initial sensing it will be unregistered Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>