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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Ensure atomicity of ungroup operation to prevent concurrent ungroup
and online processing which may lead to use-after-release situations.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Due to former patches a comment and device id initialization were
split from the addressed function call in io_subchannel_probe.
Move it back to where it belongs.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move cio_tpi() to the rest of the CONFIG_CCW_CONSOLE functions to
get rid of this one:
drivers/s390/cio/cio.c:115: warning: 'cio_tpi' defined but not used
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Hipersocket connections can encounter temporary busy conditions.
In case of the busy bit set we retry the SIGA operation immediatelly.
If the busy condition still persists after 100 ms we fail and report
the error to the upper layer. The second stage retry logic is removed.
In case of ongoing busy conditions the upper layer needs to reset the
connection.
The reporting of a SIGA error is now done synchronously to allow the
network driver to requeue the buffers. Also no error trace is created
for the temporary SIGA errors so the error message view is not flooded.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- Use automatic acknowledgement of incoming buffers in QEBSM mode
- Move ACK for non-QEBSM mode always to the newest buffer to prevent
a race with qdio_stop_polling
- Remove the polling spinlock, the upper layer drivers return new buffers
in the same code path and could not run in parallel
- Don't flood the error log in case of no-target-buffer-empty
- In handle_inbound we check if we would overwrite an ACK'ed buffer, if so
advance the pointer to the oldest ACK'ed buffer so we don't overwrite an
empty buffer in qdio_stop_polling
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- make qdio_trace a per device view
- remove s390dbf exceptions
- remove CONFIG_QDIO_DEBUG, not needed anymore if we check for the level
before calling sprintf
- use snprintf for dbf entries
- add start markers to see if the dbf view wrapped
- add a global error view for all queues
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The QEBSM instructions are only available for CONFIG_64BIT, they are not
used under 31 bit. Make compiler happy about the false positive:
drivers/s390/cio/qdio_main.c: In function ?qdio_inbound_q_done?:
drivers/s390/cio/qdio_main.c:532: warning: ?state? may be used uninitialized in this function
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add counters for the eqbs and sqbs instructions that indicate how often
we issued the instructions and how often the instructions returned with
less buffers than specified.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
qeth needs to get the port count information before
qdio has allocated a page for the chsc operation.
Extend qdio_get_ssqd_desc() to store the data in the
specified structure.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In ccw_device_move_to_orphanage(), a replacing ccw_device
is searched via get_{disc,orphaned}_ccwdev_by_dev_id()
which obtain a reference on the returned ccw_device.
This reference must be given up again after the device
has been moved to its new parent.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the memset since zeroing the string is not needed and use
snprintf instead of sprintf.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case of I/O errors on a qdio subchannel qdio_shutdown may be
called twice by the qdio driver and by zfcp. Remove the
superfluous shutdown from qdio and let the upper layer driver
handle the error condition.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Move cio's private simple udelay function to lib/delay.c and turn it
into something much more readable. So we have all implementations
at one place.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add support for z10 HiperSockets multiwrite SBALs on output
queues. This is used on LPAR with EDDP enabled devices.
Signed-off-by: Klaus-Dieter Wacker <kdwacker@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In commit e6bafba5b4, a bug was fixed that
involved converting !x & y to !(x & y). The code below shows the same
pattern, and thus should perhaps be fixed in the same way. In particular,
the result of !scsw_stctl(&request->irb.scsw) & SCSW_STCTL_STATUS_PEND is
always just !scsw_stctl(&request->irb.scsw).
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@ expression E; constant C; @@
(
!E & !C
|
- !E & C
+ !(E & C)
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix incorrect in- and output constraints, remove volatile declaration
of inline assembly parameters and reformat constraint declarations to
be more consistent.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use dev_name() in the new qdio driver.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Some further bus_id -> dev_name() conversions in s390 code.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert most s390 users setting bus_id to dev_set_name().
css and ccw busses are deferred since they need some special
treatment.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Allow users to remove blacklisted ccw devices by using the
/proc/cio_ignore interface:
echo purge > /proc/cio_ignore
will remove all devices which are offline and blacklisted.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use dedicated slow path work queue when unregistering a device due to
a user action. This ensures serialialization of other register/
unregister requests.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If an asynchronous HiperSockets queue runs full, no further packet
can be sent. In this case the next initiative to give transmitted
skbs back to the stack is triggered only by a 10-seconds qdio timer.
This timer has been introduced for low multicast traffic scenarios
to guarantee freeing of skbs in a limited amount of time. For high
HiperSocket multicast traffic scenarios progress checking on the
outbound queue should be enforced by tasklet rescheduling.
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Don't print more information than fits into the string on the
stack. Combine the informational output of qdio to fit into
one line.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The functions cio_tm_start_key and cio_start_key use the same private
orb structure of a subchannel, so the orb needs to be cleared of old
data before it is used again. A respective memset is missing from
cio_start_key and hereby added.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since 16f7f9564c, we've seen
oopses when grouping/ungrouping devices:
Unable to handle kernel pointer dereference at virtual kernel address 0000000000
114000
Oops: 0004 [#1] PREEMPT SMP
Modules linked in: bonding qeth_l2 dm_multipath sunrpc qeth_l3 dm_mod qeth chsc_
sch ccwgroup
CPU: 1 Not tainted 2.6.26-29.x.20080815-s390xdefault #1
Process iperf (pid: 24412, task: 000000003f446038, ksp: 000000003c929e08)
Krnl PSW : 0404d00180000000 000003e00006f6e6 (qeth_irq+0xda/0xb28 [qeth])
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
Krnl GPRS: 0000000000000000 000003e000000003 0000000000000000 0000000000114ccc
000000003fb82e48 000003e00006f60c 000000000000000c 000000003ce72100
0000000000114944 000000003fb82e48 0000000000114ccc 000000003fe8fd28
000003e000066000 000003e000076128 000000003fe8fdb8 000000003fe8fd28
Krnl Code: 000003e00006f6da: bf3f2024 icm %r3,15,36(%r2)
000003e00006f6de: a774023c brc 7,3e00006fb56
000003e00006f6e2: a7280000 lhi %r2,0
>000003e00006f6e6: 5020a1a0 st %r2,416(%r10)
000003e00006f6ea: 58109000 l %r1,0(%r9)
000003e00006f6ee: a7111000 tmll %r1,4096
000003e00006f6f2: a77400f9 brc 7,3e00006f8e4
000003e00006f6f6: 8810000c srl %r1,12
Call Trace:
([<000000003fe8fd20>] 0x3fe8fd20)
[<000000000033bf2a>] ccw_device_call_handler+0xb2/0xd8
[<0000000000339e1c>] ccw_device_irq+0x124/0x164
[<0000000000339758>] io_subchannel_irq+0x8c/0x118
[<00000000003309ba>] do_IRQ+0x192/0x1bc
[<0000000000114f66>] io_return+0x0/0x8
[<00000000001149cc>] sysc_do_svc+0x0/0x22
([<0000000000114a18>] sysc_noemu+0x10/0x16)
[<00000200002e047c>] 0x200002e047c
Last Breaking-Event-Address:
[<000003e00006f6d6>] qeth_irq+0xca/0xb28 [qeth]
The problem is that dev->driver_data for a ccw device is NULL,
while it should point to the ccwgroup device it is a member of.
This happened due to incorrect cleanup if creating a ccwgroup
device failed because the ccw devices were already grouped.
Fix this by setting cdev[i] to NULL in the error handling of
ccwgroup_create_from_string() after we give up our reference and
by checking if the driver_data points to the ccwgroup device in
ccwgroup_release() just to be really sure.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When disconnected ccw devices are removed, the device has to be set
offline, otherwise there will be side effects including a reference
count imbalance. This patch modifies ccw_device_offline to work for
devices in disconnecte/not operational state. ccw_device_offline is
called by cio for devices which are online during device removal.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
ssch() has two classes of return codes:
- condition codes (0-3) which need to be translated to Linux
error codes
- Linux error codes (-EIO on exceptions) which should be passed
to the caller (instead of erronously being handled like
condition code 3)
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix cleanup on error in chp_new() and init_channel_subsystem()
(must not call kfree() on structures that had been registered).
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Calling a ccw driver's notify function without the ccw device lock
held opens up a race window between discovery and handling of a change
in the device operational state. As a result, the device driver may
encounter unexpected device malfunction, leading to out-of-retry
situations or similar.
Remove race by extending the ccw device lock from state change
discovery to the calling of the notify function.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix ccw group device initialization: initialize device object before
using reference counting during cleanup.
Fixes the following message when group device initialization fails
(e.g. because too few devices where specified):
kobject: '<NULL>' (..): is not initialized, yet kobject_put() is
being called.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Increasing the qdio reference count for every used subchannel
is unnecessary since unloading qdio (if build as a module) is
only possible if other modules that use qdio are unloaded.
Unloading modules that use qdio in turn requires that these
modules shut down all qdio subchannels. Therefore the additional
module_get reference is not needed.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Improve s390 debug feature usage:
- log busy bit in dbf
- increase size of dbf views
- consistent logging of qdio api calls to setup view
- print subchannel number so one can associate the interface
with the dbf data
- only log events to one view
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If qdio_establish fails we call qdio_shutdown to cleanup the
qdio subchannel. The tiq_list entry may not be valid at that
time, therefore we must ignore queues with an invalid list entry
in tiqdio_remove_input_queues.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix the two section mismatch warnings below.
This fixes two real bugs since the code which has __exit annotations
may already be gone when it is called.
WARNING: vmlinux.o(.init.text+0x1cc4a): Section mismatch in reference from the function init_QDIO() to the function .exit.text:qdio_setup_exit()
The function __init init_QDIO() references
a function __exit qdio_setup_exit().
This is often seen when error handling in the init function
uses functionality in the exit path.
The fix is often to remove the __exit annotation of
qdio_setup_exit() so it may be used outside an exit section.
WARNING: vmlinux.o(.init.text+0x1cc7a): Section mismatch in reference from the function init_QDIO() to the function .exit.text:qdio_remove_perf_stats()
The function __init init_QDIO() references
a function __exit qdio_remove_perf_stats().
This is often seen when error handling in the init function
uses functionality in the exit path.
The fix is often to remove the __exit annotation of
qdio_remove_perf_stats() so it may be used outside an exit section.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
