Remove the unused function qdio_trace_aob.
Acked-by: NUrsula Braun <ursula.braun@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Remove unused function parameters.
Signed-off-by: NStefan Raspl <raspl@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Fix name clash with some common code device drivers and add "tod"
to all tod clock access function names.
Signed-off-by: NHeiko Carstens <heiko.carstens@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>

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>

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>

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>

Log all adapter characteristics in the s390dbf to ease debugging of
new features.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Reported-by: NRaymond Higgs <rayhiggs@us.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Currently the following mechanisms are available to move active
Linux on System z instances between machines:
* z/VM 6.2 SSI (Single System Image)
* Suspend/resume
For moving Linux instances in this patch the term LGR (Linux Guest
Relocation) is used. Because such an operation is critical, it
should be detectable from Linux. With this patch for both, a live
system and a kernel dump, the information about LGRs is accessible.
To identify a guest, stsi and stfle data is used. A new function
lgr_info_log() compares the current data (lgr_info_cur) with the
last recorded one (lgr_info_last). In case the two data sets differ,
lgr_info_cur is logged to the "lgr" s390dbf.

The following trigger points call lgr_info_log():
* panic
* die
* kdump
* LGR timer
* PSW restart
* QDIO recovery
* resume

This patch also changes the s390dbf hex_ascii view. Now only printable ASCII
characters are shown.
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Git commit 25f269f1 "[S390] qdio: EQBS retry after CCQ 96"
introduced a regression in regard to the zfcp data router.
Revoke the incorrect simplification of the function call arguments
for the qdio handler to make the zfcp hardware data router working
again.

This is applicable to 3.2+ kernels.
Signed-off-by: NSteffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: NJan Glauber <jang@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

A kernel panic may occur during sending or receiving network packets
on a machine without adapter interrupts since commit d36deae7.
The bug is triggered by writing to the shared indicator address which
is set to 0 if the machine doesn't have adapter interrupts.

Make the reading and setting of the shared indicator dependent on the
adapter interrupt feature and while at it move the code to the
file containing the adapter interrupt related code.

Thanks to Jan Jaeger for tracking this down.
Reported-by: NJan Jaeger <jan.jaeger@westnet.com.au>
Tested-by: NJan Jaeger <jan.jaeger@westnet.com.au>
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Make functions and data static to avoid sparse warnings.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The multicast poll check for the outbound queue is redundant since
3d6c76ff "[S390] qdio: outbound tasklet scan threshold". Remove the check.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Don't leave outbound SBALs in error state after a target full condition.
Reset the state to not initialized to make the error handling consistent
across all types of errors.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Running under z/VM with QIOASSIST enabled, qdio queues could stall if EQBS
did not extract all SBAL states. Add an instant retry for EQBS and, if the
retry fails, set up a timer to ensure outstanding SBALs are processed later.

While at it, optimize qdio_do_eqbs and qdio_do_sqbs to eliminate 3 jumps on
the hot path.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add a timestamp per queue and update the timestamp when the queue is
scanned. Add the queue timestamps and the timestamp of the last
adapter interrupt to the debugfs output. The timestamps are useful
for debugging stall conditions.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Current IRQ statistics support does not show detail counts for I/O
interrupts which are processed internally only. The result is a
summation count which is way off such as this one:

           CPU0       CPU1       CPU2
I/O:       1331        710        442
[...]
QAI:         15         16         16   [I/O] QDIO Adapter Interrupt
QDI:          1          0          0   [I/O] QDIO Interrupt
DAS:        706        645        381   [I/O] DASD
C15:         26         10          0   [I/O] 3215
C70:          0          0          0   [I/O] 3270
TAP:          0          0          0   [I/O] Tape
VMR:          0          0          0   [I/O] Unit Record Devices
LCS:          0          0          0   [I/O] LCS
CLW:          0          0          0   [I/O] CLAW
CTC:          0          0          0   [I/O] CTC
APB:          0          0          0   [I/O] AP Bus

Fix this by moving I/O interrupt accounting into the common I/O layer.
Signed-off-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

FICON Express8S supports hardware data router, which requires an
adapted qdio request format.
This part 1/2 provides the qdio base required for exploitation in
zfcp.
Signed-off-by: NSwen Schillig <swen@vnet.ibm.com>
Signed-off-by: NSteffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch ensures that signal adapter commands are issued if they are
indicated to be required.
Signed-off-by: NEinar Lueck <elelueck@de.ibm.com>
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces support for asynchronous delivery of storage blocks for
Hipersockets. Upper layers may exploit this functionality to reuse SBALs for
which the delivery status is still pending.
Signed-off-by: NEinar Lueck <elelueck@de.ibm.com>
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The SIGA-W may return with the busy bit set which means the device was
blocked. The busy loop which retries the SIGA-W for 100us may not be
long enough when running under a heavily loaded hypervisor.

Extend the retry mechanism by adding a longer second stage which retries
the SIGA-W for up to 10s. In difference to the first retry loop the second
stage is using mdelay to stop the cpu between the retries and thereby
avoid additional preassure in on the hypervisor.
If the second stage retry is successfull a device reset is avoided.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: NArun Sharma <asharma@fb.com>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The qdio SBAL entry flag is made-up of four different values that are
independent of one another. Some of the bits are reserved by the
hardware and should not be changed by qdio. Currently all four values
are overwritten since the SBAL entry flag is defined as an u32.

Split the SBAL entry flag into four u8's as defined by the hardware
and don't touch the reserved bits.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Prevent the following compile warning for !CONFIG_64BIT:

  CC      drivers/s390/cio/qdio_main.o
drivers/s390/cio/qdio_main.c: In function ‘handle_outbound’:
drivers/s390/cio/qdio_main.c:1449: warning: ‘state’ may be used uninitialized in this function
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The qdio hardware may surpress further interrupts as long as a SBAL is in
the error state. That can lead to unnotified data in the SBALs following
the error state. To prevent this behaviour change the SBAL[s] in error
state immediately to another program owned state so interrupts are again
received for further traffic on the device.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Reorder the initialization sequence of the qdio module to avoid
writing to an uninitialized debug feature entry. Also reorder
the exit function to restore a consistent cleanup path.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Exit do_QDIO early if the buffer count is zero to prevent side effects
in the following functions.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Prevent the following compiler warning if compiling a 31 bit kernel:

drivers/s390/cio/qdio_main.c: In function ‘get_outbound_buffer_frontier’:
drivers/s390/cio/qdio_main.c:646:16: warning: ‘state’ may be used uninitialized in this function
  CC      lib/radix-tree.o
  CC      drivers/s390/scsi/zfcp_cfdc.o
drivers/s390/cio/qdio_main.c: In function ‘qdio_inbound_q_moved’:
drivers/s390/cio/qdio_main.c:479:16: warning: ‘state’ may be used uninitialized in this function
drivers/s390/cio/qdio_main.c:479:16: note: ‘state’ was declared here
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Simplify the SIGA sync code and add unlikely annotations. In polling mode
SBALs may be accessed without interrupt, so call SIGA sync before every scan.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

HiperSocket devices only use one SBAL per qdio call without the enhanced SIGA
feature. Since that feature is currently not used remove it from the qdio code
so the compiler can generate better code for the HiperSocket outbound path.
While at it mark the SIGA error conditions as unlikely.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

If QIOASSIST is enabled for a qdio device the SIGA instruction requires
a modified function code. This function code modifier was missing for
SIGA-R and SIGA-S which can lead to a kernel panic caused by an
operand exception.

Cc: stable@kernel.org
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add a counter for outbound queue full events to the qdio statistics.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Introduce a scan treshold for the qdio outbound queues. By setting the
threshold the driver can tell qdio after how much used SBALs qdio
should schedule the outbound tasklet that scans the queue for finished
SBALs. The threshold is specific by the drivers because a
Hipersockets device is much faster in utilizing outbound buffers than a
ZFCP or OSA device.

The default values after how many used SBALs the tasklet should run are:

OSA:          > 31 SBALs
Hipersockets: > 7 SBALs
zfcp:         > 55 SBALs
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

If the shared indicator is used the following race leads to
an inbound stall:

Device                  CPU0                    CPU1
========================================================

non-shared DSCI =>1
ALSI => 1
                        Thin INT
                        ALSI => 0

                        non-shared DSCI
                        tasklets scheduled

shared DSCI => 1
ALSI => 1

                        shared DSCI => 0
                        ALSI ? -> set
                                                Thin INT
                                                ALSI => 0
                        ALSI was set,
                        shared DSCI => 1

After that no more interrupts occur because the DSCI is still set.
Fix that race by only resetting the shared DSCI if it was actually
set so the tasklets for all shared devices are scheduled and will
run after the interrupt.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Count traditional qdio interrupts and adapter interrupts for qdio
in the interrupt statistics.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Extend the qdio API to allow polling in the upper-layer driver. This
is needed by qeth to use NAPI.

To use the new interface the upper-layer driver must specify the
queue_start_poll(). This callback is used to signal the upper-layer
driver that is has initiative and must process the inbound queue by
calling qdio_get_next_buffers(). If the upper-layer driver wants to
stop polling it calls qdio_start_irq().

Since adapter interrupts are not completely stoppable qdio implements
a software bit QDIO_QUEUE_IRQS_DISABLED to safely disable interrupts for an
input queue.

The old interface is preserved and will be used as is by zfcp.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove qdio API wrappers used by qeth and replace them by calling the
appropriate functions directly.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Don't convert timestamps to microseconds, use timestamps returned by
get_clock() directly.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

If adapter interrupts are not available and traditional IO interrupts
are used for qdio the inbound tasklet continued to run if new data
arrived. That could possibly block other tasklets scheduled on the
same CPU. If new data arrives schedule the tasklet again instead of
directly processing the new data.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add missing increment for the qdio interrupt counter.
Signed-off-by: NSigned-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>