We used to unregister ccw devices not directly from the I/O
subchannel remove function in order to avoid lifelocks on the
css bus semaphore. This semaphore is gone, and there is no reason
to not unregister the ccw device directly (it is even better since
it is more in keeping with the goal of immediate disconnect).
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We allocage two pages when channel path measurements are enabled
via cm_enable. We must not forget to free them again when
channel path measurements are disabled again.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce a mutex for struct ccwgroup to prevent simuntaneous
register/unregister on the same ccwgroup device.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
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>
Path verification triggered by changes to the available CHPIDs will be
interrupted by another change but not re-started. This results in an
invalid path mask.
To solve this make sure to completely re-start path verification when
changing the available paths.
Signed-off-by: Stefan Bader <shbader@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert ccw_uevent to use add_uevent_var and adapt snprint_alias.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Detangle the online_store code and make it more readable.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Check validity flag of CHPID description data before continuing with
channel-path initialization.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Channel path status can now be modified by writing '0' and '1'
to the sysfs status attribute in addition to 'offline' and
'online' respectively.
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>
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>
Clean interface between cio and ipl code, so Peter stops complaining.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Wipe internal irb if the clear function bit is set before accumulating
bits from the irb in order to follow hardware behaviour.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Only accumulate device status field in irb if it is valid.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Make sure set_slsb problems are handled correctly in
qdio_do_qdio_fill_input() and qdio_do_qdio_fill_output.
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch (as868) adds a helper routine for device drivers that need
to set up a callback to perform some action in a different process's
context. This is intended for use by attribute methods that want to
unregister themselves or their parent device. Attribute method calls
are mutually exclusive with unregistration, so such actions cannot be
taken directly.
Two attribute methods are converted to use the new helper routine: one
for SCSI device deletion and one for System/390 ccwgroup devices.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
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>
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>
With CONFIG_SHARED_KERNEL the kernel text segment that might be in a
read only memory sections starts at 1MB. Memory between 0x12000 and
0x100000 is unused then. Free this, so we have appr. an extra MB
of memory available.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Setup.h has been misused for ipl related stuff in the past. We now move
everything, which has to do with ipl and reipl to a new header file named
"ipl.h".
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
[S390] remove __io_virt and mmiowb.
[S390] cio: use ARRAY_SIZE in device_id.c
[S390] cio: Fixup interface for setting options on ccw devices.
[S390] smp_call_function/smp_call_function_on locking.
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The current ccw_device_set_options() sets a specified mask of options
and clears those not specified, but there is no way to find out which
options have already been set.
In order to fix this up, introduce the following interface changes:
ccw_device_set_options() now only sets the specified bits, but does
not clear those that are not specified.
ccw_device_clear_options() clears the specified bits.
ccw_device_set_options_mask() provides the old semantics (setting only
the specified bits and clearing the others).
Device drivers now work as expected. qdio has been adapted.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Hopefully this will make it more maintainable and less error prone.
Code makes use of search_exception_tables(). Since it calls this
function before the kernel exeception table is sorted, there is an
early call to sort_main_extable().
This way it's easy to use the already present infrastructure of fixup
sections. Also this would allows to easily convert the rest of
head[31|64].S into C code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch adds support for clock synchronization to an external time
reference (ETR). The external time reference sends an oscillator
signal and a synchronization signal every 2^20 microseconds to keep
the TOD clocks of all connected servers in sync. For availability
two ETR units can be connected to a machine. If the clock deviates
for more than the sync-check tolerance all cpus get a machine check
that indicates that the clock is out of sync. For the lovely details
how to get the clock back in sync see the code below.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Lower priority of "Blacklisted device detected" messages so we don't
overwrite more useful messages.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change CHSC event handling to be more easily extensible.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If we have a subchannel id which has been generated via
for_each_subchannel(), it might contain an invalid subchannel set id.
We need to catch the ensuing operand exception by using stsch_err()
instead of stsch() in all possible cases.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Create/remove the channel measurement binary files with
device_{create,remove}_bin_file instead of sysfs_{create,remove}_bin_file.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Since ssd_info is now available before the subchannel is registered,
we don't need to check whether it is available.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use barrier() in stsch_reset() instead of duplicating the stsch()
inline assembly and adding "memory" to the clobberlist.
Pointed out by Chuck Ebbert.
Real fix would be to add a fixup section to the stsch() and extend the
basic program check handler so it searches the exception tables in case
of a program check.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Copy inline assembly of stsch and add "memory" to clobber list in order
to prevent gcc from optimizing away the checking of the global variable
"pgm_check_occured".
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Asynchronous probe can release memory of a subchannel before
css_get_ssd_info is called. To fix this call css_get_ssd_info
before registering with driver core.
Signed-off-by: Stefan Bader <shbader@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reboot hangs on LPARs without diag308 support. The reason for this is,
that before the reboot is done, the channel subsystem is shut down.
During the reset on each possible subchannel a "store subchannel" is
done. This operation can end in a program check interruption, if the
specified subchannel set is not implemented by the hardware. During
the reset, currently we do not have a program check handler, which
leads to the described kernel bug. We install now a new program check
handler for the reboot code to fix this problem.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A HiperSocket multicast queue works asynchronously. When sending
buffers, the buffer state change from PRIMED to EMPTY may happen
delayed. Reschedule the checking for changes in the outbound queue,
if there are still PRIMED buffers.
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- 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>
Convert the subchannel lock to a pointer to a lock. Needed for the dynamic
subchannel mapping patch.
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>
Remove CONFIG_QETH_PERF_STATS and use a sysfs attribute instead.
We want to have the ability to turn the statistics on/off at runtime.
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In io_subchannel_register(), it is better to just reprobe the current
device if it hasn't a driver yet than to rescan the whole bus.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
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>
Add some prefixes to constands defined in drivers/s390/net/qdio.h
and drivers/s390/lcs.h to make it possible to include the three
header files drivers/s390/net/qeth.h, drivers/s390/net/qdio.h and
drivers/net/s390/lcs.h in one C file. This is required for the
patch that generates the kerntypes.o file for use by lcrash.
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case of re-IPL and diag308 doesn't work we have to reset all devices
manually and wait synchronously that each reset finished.
This patch adds the necessary infrastucture and the first exploiter of it.
Subsystems that need to add a function that needs to be called at re-IPL
may register/unregister this function via
struct reset_call {
struct reset_call *next;
void (*fn)(void);
};
void register_reset_call(struct reset_call *reset);
void unregister_reset_call(struct reset_call *reset);
When the registered function get called the context is:
- all cpus beside the current one are stopped
- all machine checks and interrupts are disabled
- prefixing is disabled
- a default machine check handler is available for use
The registered functions may not take any locks are sleep.
For the common I/O layer part of this patch:
Introduce a reset_call css_reset that does the following:
- clear all subchannels
- perform a rchp on all channel paths and wait for the resulting
machine checks
This replaces the calls to clear_all_subchannels() and
cio_reset_channel_paths() for kexec and ccw reipl. reipl_ccw_dev() now
uses reipl_find_schid() to determine the subchannel id for a given
device id.
Also remove cio_reset_channel_paths() and friends since they are not
needed anymore.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
ccw_device_register() is only called from io_subchannel_register()
and io_subchannel_probe() and will never be called for possible
non-io subchannels.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move css_probe_device() behind giving up the lock for the old subchannel
in css_evaluate_known_subchannel() so we aren't disabled when we call it.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
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>
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>
Remove the last few places where a pointer to pt_regs gets passed.
Also make sure we call set_irq_regs() before irq_enter() and after
irq_exit(). This doesn't fix anything but makes sure s390 looks the
same like all other architectures.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In order to determine chpid validity, we need to check whether the
corresponding path is specified in the pim.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Retry internal operation after unit check instead of aborting them.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add timeout handler for common-I/O-layer-internal I/O operations.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Major cleanup of all s390 inline assemblies. They now have a common
coding style. Quite a few have been shortened, mainly by using register
asm variables. Use of the EX_TABLE macro helps as well. The atomic ops,
bit ops and locking inlines new use the Q-constraint if a newer gcc
is used. That results in slightly better code.
Thanks to Christian Borntraeger for proof reading the changes.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
css_evaluate_subchannel() operates subchannel without lock which can
lead to erratic behavior caused by concurrent device access. Also
split evaluation function to make it more readable.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
CHPIDs that are logically varied off will not be removed from
a CCW device's path group because resign-from-pathgroup command is
issued with invalid path mask of 0 because internal CCW operations
are masked by the logical path mask after the relevant bits are
cleared by the vary operation.
Do not apply logical path mask to internal operations.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Subchannel may incorrectly remain in state no-path after channel paths
have reappeared. Currently the scan for subchannels which are using a
channel path ends at the first occurrence if a full link address was
provided by the channel subsystem. The scan needs to continue over
all subchannels.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the MODALIAS environment variable for ccw bus uevents.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The last SLSB has to be set to STATE_PROCESSING if we really want to
use the PROCESSING feature.
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Convert GET_IPL_DEVICE assembler macro to C function.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
qdio_get_micros is supposed to return microseconds. The get_clock()
return value needs to be shifted by 12 to get to microseconds.
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use do { } while (0) constructs instead of empty defines to avoid
subtle compile bugs.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It is now possible to specify a ccw/fcp dump device which is used to
automatically create a system dump in case of a kernel panic. The dump
device can be configured under /sys/firmware/dump.
In addition it is now possible to specify a ccw/fcp device which is used
for the next reboot of Linux. The reipl device can be configured under
/sys/firmware/reipl.
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Calls to set a device online with path grouping may get stuck in
some cases because certain device conditions where discarded after
unsolicited interrupts.
Check subchannel activity after unsolicited interrupts and retry
the operation if the subchannel is idle.
Signed-off-by: Stefan Bader <shbader@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Devices enter no-path state after disabling a channel path
via the SE even though another path has been reenabled at the SE.
The devices are set into no-path state before triggering path
verification even though other paths may have become available.
To fix this trigger path verification before setting a device into
no-path state.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
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>
Do a retry of read device characteristics / read configuration
data when a deferred condition code 1 is encountered in
ccw_device_wake_up().
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fail to create a ccwgroup device if a ccw device is passed in twice.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Display avg_sample_interval in nanoseconds, like it is documented.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Add a reg_mutex to prevent unregistering a subchannel before it has been
registered. Since 2.6.17, we've seen oopses in kslowcrw when a device is
found to be not operational during sense id when doing initial device
recognition; it is not clear yet why that particular problem was not (yet)
observed with earlier kernels...
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
irqtrace support for s390.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fixes for several channel measurement facility bugs:
* Blocks copied from the hardware might not be consistent. Solve this
by moving the copying into idle state and repeating the copying.
* avg_sample_interval changed with every read, even though no new block
was available. Solve this by storing a timestamp when the last new
block was received.
* Several locking issues.
* Measurements were not reenabled after a disconnected device became
available again.
* Remove #defines for ioctls that were never implemented.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
After setting a path to a dasd offline at the SE, I/O hangs on that
dasd for 5 minutes, then continues.
I/O for which an interrupt will not be reported after the channel
path has been disabled was not terminated by the common I/O layer,
causing the dasd MIH to hit after 5 minutes.
Be more aggressive in terminating I/O after setting a channel path
offline. Also make sure to generate a fake irb if the device
driver issues an I/O request after being notified of the killed
I/O and clear residual information from the irb before trying to
start the delayed verification.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Changes in the DASD driver require an asynchronous implementation of the
subchannel reprobe loop. This loop was so far only used by the blacklisting
mechanism but is now available to all CCW device drivers.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Work around the problem that a device cannot be unregistered from
driver_for_each_device() because of klist node refcounting: Get device
after device owned by the driver to be unregistered with driver_find_device()
and then unregister it. This works because driver_get_device() gets us out of
the region of the elevated klist node refcount. driver_find_device() will
always get the next device in the list after the found one has been
unregistered.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Specify correct sizeof() in chp_measurement_read() and return
correct amount of read data.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
