Omit known to be broken paths (those set in path_noirq_mask) for the
sense/set PGID and nop IO commands.

Note: path_noirq_mask will be reset in ccw_device_verify_start (the
paths could be healthy again). However if we restart a path
verification via verify_start this mask will not be reset (there is
no need to let the wait for an interrupt time out again - plus we
do not want to loop once we deal with the paths in unknown path group
state).
Reviewed-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Do not abort path verification when waiting for an interrupt timed out.
Use path_noirq_mask to keep track of the paths used for this (also
maintain a path_notoper_mask for debugging purposes). If the timeout
happend to be during an operation where we query or alter the state of
path groups set the pgid_unknown flag.

With this change we allow usage of devices which have such ill-behaved
paths (if at least one path is operational).
Reviewed-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Cleanup the functions used to call SEI.
Also provide !CONFIG_PCI dummys for pci error handling.
Reviewed-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

cbc0dd1f "s390/pci: CHSC PCI support for error and availability events"
introduced a new SEI notification type as part of pci support.
The way SEI was called with nt2 and nt0 consecutive broke the nt0
stuff used for channel subsystem notifications.

The reason why this was broken with the mentioned patch is that you
cannot selectively disable type 0 notifications (so even when asked
for type 2 only, type 0 could be presented).

The way to do it is to tell SEI which types of notification you can
process and -this is the important part- look at the SEI result which
notification type you actually received.
Reviewed-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Tested-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Now that irq sum accounting for /proc/stat's "intr" line works again we
have the oddity that the sum field (first field) contains only the sum
of the second (external irqs) and third field (I/O interrupts).
The reason for that is that these two fields are already sums of all other
fields. So if we would sum up everything we would count every interrupt
twice.
This is broken since the split interrupt accounting was merged two years
ago: 052ff461 "[S390] irq: have detailed
statistics for interrupt types".
To fix this remove the split interrupt fields from /proc/stat's "intr"
line again and only have them in /proc/interrupts.

This restores the old behaviour, seems to be the only sane fix and mimics
a behaviour from other architectures where /proc/interrupts also contains
more than /proc/stat's "intr" line does.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

For more than two years, since f2c66cd8
"/proc/stat: scalability of irq num per cpu" the output of /proc/stat is
broken.
The first field in the "intr" line should contain the sum of all interrupts,
however since the above mentioned change it is always zero.

The reason for that is that a per cpu irq sum variable had been introduced
which got incremented when calling kstat_incr_irqs_this_cpu(). However
on s390 we directly incremented only the per cpu per irq counter by accessing
the array element via kstat_cpu(smp_processor_id()).irqs[...].
So fix this and use the kstat_incr_irqs_this_cpu() wrapper which increments
both: the per cpu per irq counter and the per cpu irq sum counter.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

For each detected qdio device a line like to following is printed:
qdio: 0.0.4102 OSA on SC 1045 using AI:1 QEBSM:0 PCI:1 TDD:1 SIGA: W AP

The PCI flag is misleading as this stands for "program controlled interrupt".
Rename it to PRI "program requested interrupt" which is more accurate and
does not interfere with another popular piece of technology.

Leave the pci string in the code since changing that would result in a huge
patch.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The check to whom a device is reserved is done by checking the path
state of the affected channel paths. If it turns out that one path is
flagged as reserved by someone else the whole device is marked as such.

However the meaning of the RESVD_ELSE bit is that the addressed device
is reserved to a different pathgroup (and not reserved to a different
LPAR). If we do this test on a path which is currently not a member of
the pathgroup we could erroneously mark the device as reserved to
someone else.

To fix this collect the reserved state for all potential members of the
pathgroup and only mark the device as reserved if all of those potential
members have the RESVD_ELSE bit set.

Cc: stable@vger.kernel.org
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin 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: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Allow drivers to enable/disable ccwgroup devices.
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Return -EINVAL if set_{on,off}line is called for already {on,off}line
devices. Also return -EINVAL for drivers which do not provide a callback
for set_{on,off}line. This behaviour is now consistent with the one for
ccw devices.
Reported-by: NStefan Raspl <raspl@linux.vnet.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Let the dasd driver and qdio use ccw_device_get_schid and
get rid of other similar functions.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This will be needed by the new virtio-ccw transport.
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Remove or replace BUG/BUG_ON where possible and convert WARN_ON
to WARN_ON_ONCE if they can occur freqeuently as pointed out by:
https://lkml.org/lkml/2012/9/27/461

Checks have been removed if:
- the error condition leads to a hardware error which gets logged
  and in most cases stops the device
- the error condition is a null pointer access
- the error condition is just pointless or already handled at
  another location
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

bitmap_or uses the number of bits as its length parameter and
not the number of words necessary to store those bits.

This fixes a regression introduced by:
	aa92b33c s390/cio: use generic bitmap functions
Reported-by: NChristian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

There's no need to keep __MAX_SUBCHANNEL and __MAX_SSID private to the
common I/O layer when __MAX_CSSID is usable by everybody.
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Do not trigger a path verification in the subchannel event
function during resume from hibernate. This will be started
by the pm_restore callback later.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NPeter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Receiving cc=3 from store subchannel means 2 things:
* the subchannel is not provided
* there are no further subchannels in this subchannel set

With this patch we abort the store subchannel loop after cc=3 (or an
exception) and clear the subsequent bits in the subchannel id set.
Reported-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Use generic bitmap functions in the subchannel id bitmap to
simplify and de-bloat the code.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Get rid of these:

arch/s390/kernel/smp.c:134:19: warning: ‘status’ may be used uninitialized in this function [-Wuninitialized]
arch/s390/mm/pgtable.c:641:10: warning: ‘table’ may be used uninitialized in this function [-Wuninitialized]
arch/s390/mm/pgtable.c:644:12: warning: ‘page’ may be used uninitialized in this function [-Wuninitialized]
drivers/s390/cio/cio.c:1037:14: warning: ‘schid’ may be used uninitialized in this function [-Wuninitialized]
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Calling debug_event the s390 debug feature only logs up to buf_size
bytes of the debug view. If debug_event is called with more bytes
than buf_size the additional data is ignored and not logged in the
debug view.

Use multiple calls to debug_event if the length exceeds buf_size.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Remove the spinlock from struct scm_device. drvdata and attributes
are guarded via device_lock.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add support for EADM interrupt statistics in /proc/interrupts.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This driver allows usage of EADM subchannels. EADM subchannels
act as a communication vehicle for SCM increments.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Detect an scm change notification in store event information.
Update affected scm devices and notify their drivers.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Bus driver to manage Storage Class Memory.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

chsc_scm_info will be used to detect all available increments of
storage class memory.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add structures to be used by the eadm subchannel driver.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add the eadm facility bits to the css characteristics and move
them to a new header.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Allow subchannel drivers build as a module to schedule subchannel work.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Make sure that the cdev pointer for IO subchannels is set to NULL when
we deregister the device (and release its last reference). This will
fix a bug were another process operates on an already freed ccw device.
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

If the subchannel event function is called from IRQ context and we
observe that the subchannel in question is gone we flag the attached
device as not operational and schedule the event function to be called
again from process context where the subchannel gets deregistered.
However if the subchannel reappeared at the time the event function
gets called from process context we would do nothing and leave the
device in not operational state. Recognize this case in sch_get_action
and trigger reexamination of the subchannel/device.
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Let the driver core handle device attribute creation and removal. This
will simplify the code and eliminates races between attribute
availability and userspace notification via uevents.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Remove the old ccwgroup_create_from_string interface since all
drivers have been converted to ccwgroup_create_dev. Also remove
now unused members of ccwgroup_driver.
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Instead of finding devices via driver_find_device use the bus_find_device
wrapper get_ccwdev_by_dev_id. This allows us to get rid of the ccw_driver
argument of ccwgroup_create_dev and thus simplify the interface.
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add a new interface for drivers to create a group device. Via the old
interface ccwgroup_create_from_string we would create a virtual device
in a way that only the caller of this function would match and bind to.

Via the new ccwgroup_create_dev we stop playing games with the driver
core and directly set the driver of the new group device. For drivers
which have todo additional setup steps (like setting driver_data)
provide a new setup driver callback.
Reviewed-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The store clock fast instruction saves a couple of instructions compared
to the store clock instruction. Always use stckf instead of stck if it
is available.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

wait_cons_dev waits for a particular subchannel to complete an I/O.
It is not necessary to use tpi to get the subchannel id as it is
already known. This avoids changes to the interrupt subclass mask
and allows to remove the lock & unlock of the subchannel lock.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Various improvements of qdio error reporting to the
upper-layer drivers (qeth, zfcp):

- Split QDIO_ERROR_ACTIVATE_CHECK_CONDITION into:

  QDIO_ERROR_ACTIVATE: qdio termination interrupt
  QDIO_ERROR_GET_BUF_STATE: QIOASSIST eqbs error
  QDIO_ERROR_SET_BUF_STATE: QIOASSIST sqbs error

  Add QDIO_ERROR_FATAL / QDIO_ERROR_TEMPORARY masks
  to ease recovery decision in upper-layer drivers.

- Don't (ab-)use qdio handler errors as return codes
  for do_QDIO but use standard error codes:

  -ENOBUFS: temporary target CC=2 condition
  -EBUSY: unresolved SIGA-W CC=2 busy condition
  -EIO: I/O error (CC=1, CC=3)

- Remove unneeded memory clobber from SIGA-R
- Remove EX_TABLE entry on SIGA-W, we want to see these errors
Reviewed-by: NUrsula Braun <ursula.braun@de.ibm.com>
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>