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path: root/drivers/s390/cio
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2009-03-31[S390] cio: online_store - trigger recognition for boxed devicesSebastian Ott
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 Ott
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 Ott
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>
2009-03-31[S390] cio: introduce ccw_device_schedule_sch_unregisterSebastian Ott
Introduce ccw_device_schedule_sch_unregister as a wrapper for queuing ccw_device_call_sch_unregister on the slow_path_wq. This wrapper will be used in the next patch. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-31[S390] cio: wake up on failed recognitionSebastian Ott
Wake up even on failed device recognition, since this may be triggered from a user trying to force a device online. With this patch a write to the online sysfs attribute will not block for ever but return with -EAGAIN in this case. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6Linus Torvalds
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (81 commits) [S390] remove duplicated #includes [S390] cpumask: use mm_cpumask() wrapper [S390] cpumask: Use accessors code. [S390] cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits. [S390] cpumask: remove cpu_coregroup_map [S390] fix clock comparator save area usage [S390] Add hwcap flag for the etf3 enhancement facility [S390] Ensure that ipl panic notifier is called late. [S390] fix dfp elf hwcap/facility bit detection [S390] smp: perform initial cpu reset before starting a cpu [S390] smp: fix memory leak on __cpu_up [S390] ipl: Improve checking logic and remove switch defaults. [S390] s390dbf: Remove needless check for NULL pointer. [S390] s390dbf: Remove redundant initilizations. [S390] use kzfree() [S390] BUG to BUG_ON changes [S390] zfcpdump: Prevent zcore from beeing built as a kernel module. [S390] Use csum_partial in checksum.h [S390] cleanup lowcore.h [S390] eliminate ipl_device from lowcore ...
2009-03-26[S390] eliminate cpuinfo_S390 structureMartin Schwidefsky
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: merge inbound and outbound handler functionsJan Glauber
The inbound and outbound handlers are nearly identical if the outbound handler uses first_to_check as end index instead of last_move. Since both values are identical at that point the handlers can be merged. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: report SIGA errors directlyJan Glauber
Errors from SIGA instructions are stored in the per queue qdio_error and reported back when the queue handler is called. That opens a race when multiple error conditions occur simultanously. Report SIGA errors immediately in the return value of do_QDIO so the upper layer can react and SIGA errors no longer interfere with other errors. Move the SIGA error handling in qeth from the outbound handler to qeth_flush_buffers. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
2009-03-26[S390] qdio: tasklet termination in case of module unloadJan Glauber
If the qdio module is unloaded the tiqdio tasklet must be terminated by tasklet_kill. Move the tasklet_kill after the unregistration of the adapter interrupt so the tiqdio tasklet will not be scheduled anymore before calling tasklet_kill. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: seperate last move index and polling indexJan Glauber
The index value that indicated that the input queue moved was also used to store the index of the first acknowledged buffer. For non-qebsm only the newest buffer is acknowledged which may be different from the last move index so two seperate values are needed to track the input queue. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: move ACK to newest buffer for devices without QEBSMJan Glauber
The ACKnowledgement state should be set on the newest SBAL so an adapter interrupt surpression check needs to scan fewer SBALs. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: call qdio_free also if qdio_shutdown failsJan Glauber
qdio_cleanup is a wrapper function that should call qdio_shutdown and qdio_free. qdio_free was not called if an error occured in qdio_shutdown resulting in a missing free of allocated resources. Call qdio_free regardless of the return value of qdio_shutdown. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: proper kill of qdio taskletsJan Glauber
The queue tasklets were stopped with tasklet_disable. Although tasklet_disable prevents the tasklet from beeing executed it is still possible that a tasklet is scheduled on a CPU at that point. A following qdio_establish calls tasklet_init which clears the tasklet count and the tasklet state leading to the following Oops: <2>kernel BUG at kernel/softirq.c:392! <4>illegal operation: 0001 [#1] SMP <4>Modules linked in: iptable_filter ip_tables x_tables dm_round_robin dm_multipath scsi_dh sg sd_mod crc_t10dif nfs lockd nfs _acl sunrpc fuse loop dm_mod qeth_l3 ipv6 zfcp qeth scsi_transport_fc qdio scsi_tgt scsi_mod chsc_sch ccwgroup dasd_eckd_mod dasdm od ext3 mbcache jbd <4>Supported: Yes <4>CPU: 0 Not tainted 2.6.27.13-1.1.mz13-default #1 <4>Process blast.LzS_64 (pid: 16445, task: 000000006cc02538, ksp: 000000006cb67998) <4>Krnl PSW : 0704c00180000000 00000000001399f4 (tasklet_action+0xc8/0x1d4) <4> R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3 <4>Krnl GPRS: ffffffff00000030 0000000000000002 0000000000000002 fffffffffffffffe <4> 000000000013aabe 00000000003b6a18 fffffffffffffffd 0000000000000000 <4> 00000000006705a8 000000007d0914a8 000000007d0914b0 000000007fecfd30 <4> 0000000000000000 00000000003b63e8 000000007fecfd90 000000007fecfd30 <4>Krnl Code: 00000000001399e8: b9200021 cgr %r2,%r1 <4> 00000000001399ec: a7740004 brc 7,1399f4 <4> 00000000001399f0: a7f40001 brc 15,1399f2 <4> >00000000001399f4: c0100027e8ee larl %r1,636bd0 <4> 00000000001399fa: bf1f1008 icm %r1,15,8(%r1) <4> 00000000001399fe: a7840019 brc 8,139a30 <4> 0000000000139a02: c0300027e8ef larl %r3,636be0 <4> 0000000000139a08: e3c030000004 lg %r12,0(%r3) <4>Call Trace: <4>([<0000000000139c12>] tasklet_hi_action+0x112/0x1d4) <4> [<000000000013aabe>] __do_softirq+0xde/0x1c4 <4> [<000000000010fa2e>] do_softirq+0x96/0xb0 <4> [<000000000013a8d8>] irq_exit+0x70/0xcc <4> [<000000000010d1d8>] do_extint+0xf0/0x110 <4> [<0000000000113b10>] ext_no_vtime+0x16/0x1a <4> [<000003e0000a3662>] ext3_dirty_inode+0xe6/0xe8 [ext3] <4>([<00000000001f6cf2>] __mark_inode_dirty+0x52/0x1d4) <4> [<000003e0000a44f0>] ext3_ordered_write_end+0x138/0x190 [ext3] <4> [<000000000018d5ec>] generic_perform_write+0x174/0x230 <4> [<0000000000190144>] generic_file_buffered_write+0xb4/0x194 <4> [<0000000000190864>] __generic_file_aio_write_nolock+0x418/0x454 <4> [<0000000000190ee2>] generic_file_aio_write+0x76/0xe4 <4> [<000003e0000a05c2>] ext3_file_write+0x3e/0xc8 [ext3] <4> [<00000000001cc2fe>] do_sync_write+0xd6/0x120 <4> [<00000000001ccfc8>] vfs_write+0xac/0x184 <4> [<00000000001cd218>] SyS_write+0x68/0xe0 <4> [<0000000000113402>] sysc_noemu+0x10/0x16 <4> [<0000020000043188>] 0x20000043188 <4>Last Breaking-Event-Address: <4> [<00000000001399f0>] tasklet_action+0xc4/0x1d4 <6>qdio: 0.0.c61b ZFCP on SC f67 using AI:1 QEBSM:0 PCI:1 TDD:1 SIGA: W AOP <4> <0>Kernel panic - not syncing: Fatal exception in interrupt Use tasklet_kill instead of tasklet_disbale. Since tasklet_schedule must not be called after tasklet_kill use the QDIO_IRQ_STATE_STOPPED to inidicate that a queue is going down and prevent further tasklet schedules in that case. Remove superflous tasklet_schedule from input queue setup, at that time the queues are not ready so the schedule results in a NOP. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: Dont call qdio_shutdown in case qdio_activate failsJan Glauber
Remove the call to qdio_shutdown from qdio_activate since the upper-layer drivers are responsible to call qdio_shutdown when qdio_activate returns with an error. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: add missing tiq_list lockingJan Glauber
Add a mutex to protect the tiq_list. Although reading the list is done using RCU adding and removing elements from the list must still happen locked since multiple qdio devices may change the list in parallel otherwise. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: prevent workqueue deadlockPeter Oberparleiter
Subchannel reprobing can block the kslowcrw workqueue indefinitely while waiting for device recognition to finish which is also scheduled to run on kslowcrw. Prevent this deadlock by moving the waiting portion of subchannel reprobing to the cio workqueue. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: remove unused local variableSebastian Ott
Remove unused subchannel pointer in io_subchannel_recog_done. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: incorrect status check in interrogate functionPeter Oberparleiter
Fix incorrect check for active I/O in interrogate function. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: fix rc generation after chsc callSebastian Ott
In some situations a rc in __chsc_do_secm will be overwritten by another one. This shouldn't do harm since todays callers don't check for _specific_ errors but fix it for the sake of correctness. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: fix wrong buffer access in cio_ignore_writeSebastian Ott
Writing only spaces to /proc/cio_ignore will cause a buffer overflow since the size_t value i will not become negative and so buf[-1UL] is accessed. Change the value of i to ssize_t. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ccw group fix unbind behaviour.Sebastian Ott
For a ccw group device unbinding it from its driver should do the same as a call to ungroup, since this virtual device can not exist without a driver. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: fix sanity checks in ccwgroup driver.Sebastian Ott
Some sanity checks in the ccw group driver test the output of container_of macros to be !NULL. Test the input parameters instead. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ccw group online store - report rcs to the caller.Sebastian Ott
In case the ccw group driver refuses to set a device [on|off]line, we should transmit the return code to the caller. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: airq - fix array boundarySebastian Ott
MAX_ISC is a valid isc number, so arrays with an index of isc need to have a length of MAX_ISC+1 Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: device scan oom fallback.Sebastian Ott
Since some callers rely on for_each_subchannel_staged to not fail, fall back to brute force scanning using get_subchannel_by_schid in case of a oom situation. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ensure single load of irq handler pointerHeiko Carstens
Add barrier to prevent compiler from reloading pointer to irq handler. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio/crw: add/fix lockingHeiko Carstens
The crw_unregister_handler uses xchg + synchronize_sched when unregistering a crw_handler. This doesn't protect crw_collect_info to potentially jump to NULL since it has unlocked code like this: if (crw_handlers[i]) crw_handlers[i](NULL, NULL, 1); So add a mutex which protects the crw handler array for changes. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ccw device online store - report rc from ccw driver.Sebastian Ott
In case the ccw driver refuses to set a device offline, we should transmit the return code to the caller. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: Use ccw_device_set_notoper().Cornelia Huck
Use ccw_device_set_notoper() (which also deletes the device timer and disables the subchannel) instead of simply setting the state to DEV_STATE_NOT_OPER in the generic not operational handling code. This prevents unexpected interrupts popping up for devices that are deemed not operational. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: Try harder to disable subchannel.Cornelia Huck
Acting upon the assumption that cio_disable_subchannel() is only called when we really want to disable the subchannel (a) remove the check for activity (it is already done in ccw_device_offline(), which is the place where it matters) (b) collect pending status via tsch() and ignore it (it can't matter anymore since the subchannel will be disabled). Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: Use unbind/bind instead of unregister/register.Cornelia Huck
The common I/O layer may encounter a situation where the device number of a ccw device has changed or a device driver doesn't want to keep a formerly disconnected device becoming operational again. Instead of using device_del()/ device_add() as now, we can just unbind the driver from the device and rebind it to get the desired effect (rebinding) with less overhead. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] split/move machine check handler codeHeiko Carstens
Split machine check handler code and move it to cio and kernel code where it belongs to. No functional change. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-24sysfs: only allow one scheduled removal callback per kobjAlex Chiang
The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24Driver core: Fix device_move() vs. dpm list ordering, v2Cornelia Huck
dpm_list currently relies on the fact that child devices will be registered after their parents to get a correct suspend order. Using device_move() however destroys this assumption, as an already registered device may be moved under a newly registered one. This patch adds a new argument to device_move(), allowing callers to specify how dpm_list should be adapted. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24Driver core: implement uevent suppress in kobjectMing Lei
This patch implements uevent suppress in kobject and removes it from struct device, based on the following ideas: 1,Uevent sending should be one attribute of kobject, so suppressing it in kobject layer is more natural than in device layer. By this way, we can do it for other objects embedded with kobject. 2,It may save several bytes for each instance of struct device.(On my omap3(32bit ARM) based box, can save 8bytes per device object) This patch also introduces dev_set|get_uevent_suppress() helpers to set and query uevent_suppress attribute in case to help kobject as private part of struct device in future. [This version is against the latest driver-core patch set of Greg,please ignore the last version.] Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-09[S390] qdio: fix broken pointer in case of CONFIG_DEBUG_FS is disabledJan Glauber
If CONFIG_DEBUG_FS is disabled debugfs_create_file returns -ENODEV instead of zero. Since the return value is stored and used at shutdown to remove existing entries an OOPS may be triggered. Add a check of the debugfs_create_file return value and in case of an error set the entry to NULL so it will be ignored at shutdown. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-01-08fix similar typos to successfullColy Li
When I review ocfs2 code, find there are 2 typos to "successfull". After doing grep "successfull " in kernel tree, 22 typos found totally -- great minds always think alike :) This patch fixes all the similar typos. Thanks for Randy's ack and comments. Signed-off-by: Coly Li <coyli@suse.de> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: Jeff Garzik <jeff@garzik.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Vlad Yasevich <vladislav.yasevich@hp.com> Cc: Sridhar Samudrala <sri@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-31[PATCH] improve idle cputime accountingMartin Schwidefsky
Distinguish the cputime of the idle process where idle is actually using cpu cycles from the cputime where idle is sleeping on an enabled wait psw. The former is accounted as system time, the later as idle time. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] convert cio printks to pr_xxx macros.Michael Ernst
Signed-off-by: Michael Ernst <mernst@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: use pim to check for multipath.Sebastian Ott
To check if multipath is available we count the bits set in lpm, which could change over time (via configure [on|off] of a path). The following patch uses the pim (which is persistent) for this decision. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: commit all pmcw changes.Sebastian Ott
Sometimes we change the pmcw configuration but don't call msch to transmit these changes to the channel subsystem. The patch fixes this by calling cio_commit_config in such cases. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: introduce cio_commit_configSebastian Ott
To change the configuration of a subchannel we alter the modifiable bits of the subchannel's schib field and issue a modify subchannel. There can be the case that not all changes were applied -or worse- quietly overwritten by the hardware. With the next store subchannel we obtain the current state of the hardware but lose our target configuration. With this patch we introduce a subchannel_config structure which contains the target subchannel configuration. Additionally the msch wrapper cio_modify is replaced with cio_commit_config which copies the desired changes to a temporary schib. msch is then called with the temporary schib. This schib is only written back to the subchannel if all changes were applied. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: introduce cio_update_schibSebastian Ott
There is the chance that we get condition code 0 for a stsch but the resulting schib is not vaild. In the current code there are 2 cases: * we do a check for validity of the schib after stsch, but at this time we have already stored the invaild schib in the subchannel structure. This may lead to problems. * we don't do a check for validity, which is not that good either. The patch addresses both issues by introducing the stsch wrapper cio_update_schib which performs stsch on a local schib. This schib is only written back to the subchannel if it's valid. side note: For some functions (chp_events) the return codes are different now (-ENXIO vs -ENODEV) but this shouldn't do harm since the caller doesn't check for _specific_ errors. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: Use device_is_registered().Cornelia Huck
Check if a ccw device is registered via device_is_registered() and not via the old kludge of checking the membership in driver core internal klists. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: Dont call ->release directly.Cornelia Huck
Just put the cdev's reference count to give up our reference. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: Dont fail probe for I/O subchannels.Cornelia Huck
If we fail the probe for an I/O subchannel, we won't be able to unregister it again since there are no sch_event() callbacks for unbound subchannels. Just succeed the probe in any case and schedule unregistering the subchannel. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: Only register ccw_device for registered subchannel.Cornelia Huck
There is a race between io_subchannel_register() and io_subchannel_sch_event() which may cause a subchannel to be unregistered because it is no longer operational before io_subchannel_register() had run. We need to check whether the subchannel is still registered before the ccw device can be registered and just bail out if it is not. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: Fix I/O subchannel refcounting.Cornelia Huck
Subchannel refcounting was incorrect in some places, especially a refcount was missing when ccw_device_call_sch_unregister() was called and the refcount was not correctly switched after moving devices. Fix this by establishing the following rules: - The ccw_device obtains a reference on its parent subchannel when dev.parent is set and gives it up in its release function. This is needed because we need a parent reference for correct refcounting even before the ccw device is (if at all) registered. - When calling device_move(), obtain a reference on the new subchannel before moving the ccw device and give up the reference on the old parent after moving. This brings the refcount in line with the first rule. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] cio: Fix reference counting for online/offline.Cornelia Huck
The current code attempts to get an extra reference count for online devices by doing a get_device() in ccw_device_online() and a put_device() in ccw_device_done(). However, this - incorrectly obtains an extra reference for disconnected devices becoming available again (since they are already online) - needs special checks for css_init_done in order to handle the console device - is not obvious and - may incorretly drop a reference count in ccw_device_done() if that function is called after path verification for a device that just became not operational. So let's just get the reference in ccw_device_set_online() and drop it in ccw_device_set_offline(). (Unfortunately, we still need the special case in io_subchannel_probe().) Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>