Commit Graph

399 Commits

Author SHA1 Message Date
Martin Schwidefsky
6664845cef [S390] cio: force console function
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 10:31:11 +02:00
Cornelia Huck
ad285ae9fc [S390] pm: chsc subchannel driver power management callbacks
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 10:31:10 +02:00
Cornelia Huck
93a275921d [S390] pm: io subchannel driver power management callbacks
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 10:31:09 +02:00
Sebastian Ott
dcbd16d511 [S390] pm: css bus power management callbacks
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-16 10:31:09 +02:00
Sebastian Ott
7e597a21a1 [S390] pm: ccwgroup bus power management callbacks
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-16 10:31:08 +02:00
Sebastian Ott
823d494ac1 [S390] pm: ccw bus power management callbacks
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-16 10:31:08 +02:00
Heiko Carstens
88dbd20372 [S390] ftrace: add function graph tracer support
Function graph tracer support for s390.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12 10:27:39 +02:00
Roel Kluin
6b9d8e80bb [S390] qdio: fix access beyond ARRAY_SIZE of irq_ptr->{in,out}put_qs
Do not go beyond ARRAY_SIZE of irq_ptr->{in,out}put_qs

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12 10:27:34 +02:00
Jan Glauber
a7c65a559a [S390] qdio: inline qdio_perf_stat_inc
Move qdio_perf_stat_inc to the header file so it can be inlined.
Remove unused qdio_perf_stat_dec.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12 10:27:32 +02:00
Jan Glauber
4c57542320 [S390] qdio: simplify error handling in irq handler
The check for the device status in qdio_establish_handle_irq()
had dead code. Remove the unused code and simplify the error
handling.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12 10:27:32 +02:00
Sebastian Ott
e45efa99b0 [S390] cio: fix sanity checks in device_ops.
Some sanity checks in device_ops.c 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>
2009-06-12 10:27:31 +02:00
Martin Schwidefsky
76d4e00a05 [S390] merge cpu.h into cputime.h
All definition in cpu.h have to do with cputime accounting. Move
them to cputime.h and remove the header file.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-12 10:27:29 +02:00
Jan Glauber
75cb71f318 [S390] qdio: remove dead timeout handler
The QDIO ccw devices are started by ccw_device_start so no timeout
can occur for the interrupt handler. Remove the dead code.

In case of an I/O error set the device state to error and wake up
a possibly running qdio_shutdown waiter.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14 15:37:24 +02:00
Sebastian Ott
99f6a570ee [S390] cio: online_store - trigger recognition for boxed devices
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 19:17:07 +02:00
Sebastian Ott
b5cd99e6b0 [S390] cio: disallow online setting of device in transient state
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 19:17:06 +02:00
Sebastian Ott
47593bfa10 [S390] cio: introduce notifier for boxed state
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 19:17:06 +02:00
Sebastian Ott
c4621a6264 [S390] cio: introduce ccw_device_schedule_sch_unregister
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 19:17:05 +02:00
Sebastian Ott
156013ffd1 [S390] cio: wake up on failed recognition
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>
2009-03-31 19:17:03 +02:00
Linus Torvalds
21cdbc1378 Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
* '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 16:04:22 -07:00
Martin Schwidefsky
7b4684880d [S390] eliminate cpuinfo_S390 structure
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:26 +01:00
Jan Glauber
9c8a08d7a7 [S390] qdio: merge inbound and outbound handler functions
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 15:24:22 +01:00
Jan Glauber
d303b6fd85 [S390] qdio: report SIGA errors directly
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 15:24:22 +01:00
Jan Glauber
9e890ad880 [S390] qdio: tasklet termination in case of module unload
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 15:24:21 +01:00
Jan Glauber
e85dea0e41 [S390] qdio: seperate last move index and polling index
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 15:24:21 +01:00
Jan Glauber
3fdf1e18cb [S390] qdio: move ACK to newest buffer for devices without QEBSM
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 15:24:21 +01:00
Jan Glauber
700e982f28 [S390] qdio: call qdio_free also if qdio_shutdown fails
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 15:24:20 +01:00
Jan Glauber
c38f960809 [S390] qdio: proper kill of qdio tasklets
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 15:24:20 +01:00
Jan Glauber
e4c14e2085 [S390] qdio: Dont call qdio_shutdown in case qdio_activate fails
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 15:24:20 +01:00
Jan Glauber
b454740246 [S390] qdio: add missing tiq_list locking
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 15:24:19 +01:00
Peter Oberparleiter
56e25e9777 [S390] cio: prevent workqueue deadlock
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 15:24:18 +01:00
Sebastian Ott
0cc110651b [S390] cio: remove unused local variable
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 15:24:17 +01:00
Peter Oberparleiter
7a968f0565 [S390] cio: incorrect status check in interrogate function
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 15:24:17 +01:00
Sebastian Ott
17e7d87d9f [S390] cio: fix rc generation after chsc call
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 15:24:16 +01:00
Sebastian Ott
94cbc203be [S390] cio: fix wrong buffer access in cio_ignore_write
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 15:24:16 +01:00
Sebastian Ott
e909074bb9 [S390] cio: ccw group fix unbind behaviour.
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 15:24:16 +01:00
Sebastian Ott
50f1548399 [S390] cio: fix sanity checks in ccwgroup driver.
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 15:24:15 +01:00
Sebastian Ott
40c9f9992b [S390] cio: ccw group online store - report rcs to the caller.
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 15:24:15 +01:00
Sebastian Ott
a1f640734a [S390] cio: airq - fix array boundary
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 15:24:14 +01:00
Sebastian Ott
90ac24a5ae [S390] cio: device scan oom fallback.
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 15:24:14 +01:00
Heiko Carstens
87fa5af80c [S390] cio: ensure single load of irq handler pointer
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 15:24:14 +01:00
Heiko Carstens
98c1c68252 [S390] cio/crw: add/fix locking
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 15:24:13 +01:00
Sebastian Ott
e74fe0cec9 [S390] cio: ccw device online store - report rc from ccw driver.
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 15:24:13 +01:00
Cornelia Huck
c08f294a14 [S390] cio: Use ccw_device_set_notoper().
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 15:24:13 +01:00
Cornelia Huck
ed04b892e2 [S390] cio: Try harder to disable subchannel.
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 15:24:12 +01:00
Cornelia Huck
eb32ae8d0e [S390] cio: Use unbind/bind instead of unregister/register.
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 15:24:12 +01:00
Heiko Carstens
f5daba1d41 [S390] split/move machine check handler code
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>
2009-03-26 15:24:10 +01:00
Alex Chiang
669420644c sysfs: only allow one scheduled removal callback per kobj
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>
2009-03-24 16:38:26 -07:00
Cornelia Huck
ffa6a7054d Driver core: Fix device_move() vs. dpm list ordering, v2
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>
2009-03-24 16:38:26 -07:00
Ming Lei
f67f129e51 Driver core: implement uevent suppress in kobject
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>
2009-03-24 16:38:26 -07:00
Jan Glauber
19cdd08ba1 [S390] qdio: fix broken pointer in case of CONFIG_DEBUG_FS is disabled
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>
2009-01-09 12:15:07 +01:00