Commit graph

19 commits

Author SHA1 Message Date
Sebastian Ott 623bd44d3f s390/pci: improve pci hotplug
PCI hotplug events basically notify about the new state of a
function. Unfortunately some hypervisors implement hotplug
events in a way where it is not clear what the new state of
the function should be.

Use clp_get_state to find the current state of the function
and handle accordingly.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-28 07:32:12 +02:00
Markus Elfring 64a40c8400 s390/pci: Delete an unnecessary check before the function call "pci_dev_put"
The pci_dev_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-07-18 10:17:24 +02:00
Sebastian Ott 9a99649f2a s390/pci: remove pdev pointer from arch data
For each PCI function we need to maintain arch specific data in
struct zpci_dev which also contains a pointer to struct pci_dev.

When a function is registered or deregistered (which is triggered by PCI
common code) we need to adjust that pointer which could interfere with
the machine check handler (triggered by FW) using zpci_dev->pdev.

Since multiple instances of the same pdev could exist at a time this can't
be solved with locking.

Fix that by ditching the pdev pointer and use a bus walk to reach
struct pci_dev (only one instance of a pdev can be registered at the bus
at a time).

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-23 08:56:16 +01:00
Sebastian Ott 8ead7efb63 s390/pci: set error state for unusable functions
We receive special notifications from firmware when an error was detected
and a pci function became unusable. Set the error_state accordingly to give
device drivers a hint that they don't need to try error recovery.

Suggested-by: Alexander Schmidt <alexschm@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-26 12:46:28 +01:00
Sebastian Ott 2a01bd1bd3 s390/pci: use pci_rescan_remove_lock
Make sure that we use the pci_rescan_remove_lock when we remove
or add functions from/to the bus.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-07-29 09:11:56 +02:00
Sebastian Ott 515f022e8b s390/pci: handle events for unused functions
Receiving error events for a pci function that's currently not in use
will crash the kernel. For example the procedure for FW upgrades might
include:
* remove the function from Linux
* apply FW upgrade
* rescan for new functions

Receiving an event during the FW upgrade will result in a use after free
when printing the functions name. Just print "n/a" in such cases.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-07-29 09:11:52 +02:00
Sebastian Ott 7fc611ff3f s390/pci: improve handling of hotplug event 0x301
Hypervisors may deliver event 0x301 not only for standby
but also for reserved devices.
Just handle event 0x301 regardless of the device's state.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-06-18 15:45:54 +02:00
Gerald Schaefer 896cb7e635 s390/pci: fix kmsg component
KMSG_COMPONENT has to be defined instead of COMPONENT.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-07-22 09:26:21 +02:00
Sebastian Ott ca25f564c4 s390/pci: improve state check when processing hotplug events
Processing pci hotplug events can fail when a pci function is in an
unexpected state. This can happen when we already processed the
change associated with the hotplug event (especially when receiving
hotplug events during early boot).
Just ignore the event in this case.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-05-20 08:58:48 +02:00
Linus Torvalds f479c01c8e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "The bulk of the s390 updates for v3.14.

  New features are the perf support for the CPU-Measurement Sample
  Facility and the EP11 support for the crypto cards.  And the normal
  cleanups and bug-fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (44 commits)
  s390/cpum_sf: fix printk format warnings
  s390: Fix misspellings using 'codespell' tool
  s390/qdio: bridgeport support - CHSC part
  s390: delete new instances of __cpuinit usage
  s390/compat: fix PSW32_USER_BITS definition
  s390/zcrypt: add support for EP11 coprocessor cards
  s390/mm: optimize randomize_et_dyn for !PF_RANDOMIZE
  s390: use IS_ENABLED to check if a CONFIG is set to y or m
  s390/cio: use device_lock to synchronize calls to the ccwgroup driver
  s390/cio: use device_lock to synchronize calls to the ccw driver
  s390/cio: fix unlocked access of online member
  s390/cpum_sf: Add flag to process full SDBs only
  s390/cpum_sf: Add raw data sampling to support the diagnostic-sampling function
  s390/cpum_sf: Filter perf events based event->attr.exclude_* settings
  s390/cpum_sf: Detect KVM guest samples
  s390/cpum_sf: Add helper to read TOD from trailer entries
  s390/cpum_sf: Atomically reset trailer entry fields of sample-data-blocks
  s390/cpum_sf: Dynamically extend the sampling buffer if overflows occur
  s390/pci: reenable per default
  s390/pci/dma: fix accounting of allocated_pages
  ...
2014-01-20 09:23:31 -08:00
Sebastian Ott fcf2f40293 s390/pci: obtain function handle in hotplug notifier
When using the CLP interface to enable or disable a pci device a
valid function handle needs to be delivered. So far our assumption
was that we always have an up-to-date version of the function handle
(since it doesn't change when the device is in use). This assumption
is incorrect if the pci device is enabled or disabled outside of our
control. When we are notified about such a change we already receive
the new function handle. Just use it.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-30 11:28:47 +01:00
Sebastian Ott 0c0c277692 s390/pci: set error state for unavailable functions
If we receive a notification that a pci function became unavailable we clean
up by removing the pci device. This can confuse the driver since the function
is already unaccessible. Improve this situation by setting an appropriate
error_state.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:55 +01:00
Sebastian Ott 704268925d s390/pci: fix removal of nonexistent pci bus
If we remove a pci bus after receiving a hotplug notification we need
to check if the bus is actually present (creation of the pci bus
during an earlier notification may have been failed).

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:54 +01:00
Sebastian Ott aa3b7c2967 s390/pci: prevent inadvertently triggered bus scans
Initialization and scanning of the pci bus is omitted on older
machines without pci support or if pci=off was specified. Remember
the fact that we ran without pci support and prevent further bus
scans during resume from hibernate or after receiving hotplug
notifications.

Reported-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:54 +01:00
Sebastian Ott d795ddad36 s390/pci: implement hotplug notifications
When the availability of a pci function has changed by means
outside of our control we receive an availability event.
Implement/improve the handling of these notifications.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-11-15 14:08:42 +01:00
Sebastian Ott 1f1dcbd4f2 s390/pci: message cleanup
Cleanup arch specific pci messages. Remove unhelpful messages and
replace others with entries in the debugfs.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24 17:17:15 +02:00
Sebastian Ott 1d57896638 s390/pci: split lpf
List pci functions is used to query and iterate over pci functions.
This function currently has 2 users - initial device discovery and
rescan after a machine check. Instead of having a multipurpose
function pass a callback which gets called for each pci function.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:17 +02:00
Jan Glauber d0b0885316 s390/pci: performance statistics and debug infrastructure
Add support for reading the PCI function measurement block counters
provided by the hypervisor. Add two s390 debug features, one for
critical errors and one for tracing and provide wrappers to log data.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-12-14 10:01:17 +01:00
Jan Glauber cbc0dd1f85 s390/pci: CHSC PCI support for error and availability events
Add CHSC store-event-information support for PCI (notfication type 2)
and report error and availability events to the PCI architecture layer.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-11-30 17:47:24 +01:00