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>
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>
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>
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>
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>
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>
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>
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>
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
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
