s390/cio: add CRW inject functionality

This patch introduces the mechanism to inject artificial events to the
CIO layer.

One of the main-event type which triggers the CommonIO operations are
Channe

s390/cio: add CRW inject functionality

This patch introduces the mechanism to inject artificial events to the
CIO layer.

One of the main-event type which triggers the CommonIO operations are
Channel Report events. When a malfunction or other condition affecting
channel-subsystem operation is recognized, a Channel Report Word
(consisting of one or more CRWs) describing the condition is made
pending for retrieval and analysis by the program. The CRW contains
information concerning the identity and state of a facility following
the detection of the malfunction or other condition.

The patch introduces two debugfs interfaces which can be used to inject
'artificial' events from the userspace. It is intended to provide an easy
means to increase the test coverage for CIO code. And this functionality
can be enabled via a new configuration option CONFIG_CIO_INJECT.

The newly introduces debugfs interfaces can be used as mentioned below
to generate different fake-events. To use the crw_inject, first we should
enable it by using enable_inject interface.
i.e

echo 1 > /sys/kernel/debug/s390/cio/enable_inject

After the first step, user can simulate CRW as follows:

echo <solicited> <overflow> <chaining> <rsc> <ancillary> <erc> <rsid> \
> /sys/kernel/debug/s390/cio/crw_inject

Example:
A permanent error ERC on CHPID 0x60 would look like this:

echo 0 0 0 4 0 6 0x60 > /sys/kernel/debug/s390/cio/crw_inject

and an initialized ERC on the same CHPID:

echo 0 0 0 4 0 2 0x60 > /sys/kernel/debug/s390/cio/crw_inject

Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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s390/cio: introduce CIO debugfs directory

This patch introduces an s390 Common I/O layer debugfs directory that is
intended to provide access to debugging-related CIO functions and data.
The directo

s390/cio: introduce CIO debugfs directory

This patch introduces an s390 Common I/O layer debugfs directory that is
intended to provide access to debugging-related CIO functions and data.
The directory is created as /sys/kernel/debug/s390/cio

Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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vfio-ccw: Introduce a new schib region

The schib region can be used by userspace to get the subchannel-
information block (SCHIB) for the passthrough subchannel.
This can be useful to get informatio

vfio-ccw: Introduce a new schib region

The schib region can be used by userspace to get the subchannel-
information block (SCHIB) for the passthrough subchannel.
This can be useful to get information such as channel path
information via the SCHIB.PMCW fields.

Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200505122745.53208-5-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

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vfio-ccw: Refactor how the traces are built

Commit 3cd90214b70f ("vfio: ccw: add tracepoints for interesting error
paths") added a quick trace point to determine where a channel program
failed while

vfio-ccw: Refactor how the traces are built

Commit 3cd90214b70f ("vfio: ccw: add tracepoints for interesting error
paths") added a quick trace point to determine where a channel program
failed while being processed. It's a great addition, but adding more
traces to vfio-ccw is more cumbersome than it needs to be.

Let's refactor how this is done, so that additional traces are easier
to add and can exist outside of the FSM if we ever desire.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20191016142040.14132-2-farman@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

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vfio-ccw: add handling for async channel instructions

Add a region to the vfio-ccw device that can be used to submit
asynchronous I/O instructions. ssch continues to be handled by the
existing I/O r

vfio-ccw: add handling for async channel instructions

Add a region to the vfio-ccw device that can be used to submit
asynchronous I/O instructions. ssch continues to be handled by the
existing I/O region; the new region handles hsch and csch.

Interrupt status continues to be reported through the same channels
as for ssch.

Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

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vfio: ccw: add tracepoints for interesting error paths

Add some tracepoints so we can inspect what is not working as is should.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Dong

vfio: ccw: add tracepoints for interesting error paths

Add some tracepoints so we can inspect what is not working as is should.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.ibm.com>
Message-Id: <20180523025645.8978-5-bjsdjshi@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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vfio: ccw: introduce a finite state machine

The current implementation doesn't check if the subchannel is in a
proper device state when handling an event. Let's introduce
a finite state machine to m

vfio: ccw: introduce a finite state machine

The current implementation doesn't check if the subchannel is in a
proper device state when handling an event. Let's introduce
a finite state machine to manage the state/event change.

Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-14-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

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vfio: ccw: register vfio_ccw to the mediated device framework

To make vfio support subchannel devices, we need to leverage the
mediated device framework to create a mediated device for the
subchanne

vfio: ccw: register vfio_ccw to the mediated device framework

To make vfio support subchannel devices, we need to leverage the
mediated device framework to create a mediated device for the
subchannel device.

This registers the subchannel device to the mediated device
framework during probe to enable mediated device creation.

Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-7-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

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vfio: ccw: introduce channel program interfaces

Introduce ccwchain structure and helper functions that can be used to
handle a channel program issued from a virtual machine.

The following limitatio

vfio: ccw: introduce channel program interfaces

Introduce ccwchain structure and helper functions that can be used to
handle a channel program issued from a virtual machine.

The following limitations apply:
1. Supports only prefetch enabled mode.
2. Supports idal(c64) ccw chaining.
3. Supports 4k idaw.
4. Supports ccw1.
5. Supports direct ccw chaining by translating them to idal ccws.

CCW translation requires to leverage the vfio_(un)pin_pages interfaces
to pin/unpin sets of mem pages frequently. Currently we have a lack of
support to do this in an efficient way. So we introduce pfn_array data
structure and helper functions to handle pin/unpin operations here.

Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-6-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

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vfio: ccw: basic implementation for vfio_ccw driver

To make vfio support subchannel devices, we need a css driver for
the vfio subchannels. This patch adds a basic vfio-ccw subchannel
driver for thi

vfio: ccw: basic implementation for vfio_ccw driver

To make vfio support subchannel devices, we need a css driver for
the vfio subchannels. This patch adds a basic vfio-ccw subchannel
driver for this purpose.

To enable VFIO for vfio-ccw, enable S390_CCW_IOMMU config option
and configure VFIO as required.

Acked-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-5-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

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s390/cio: Change I/O instructions from inline to normal functions

Adding tracepoints to inline functions adds tracepoint invocation code
for each instance where the function is inlined. The resultin

s390/cio: Change I/O instructions from inline to normal functions

Adding tracepoints to inline functions adds tracepoint invocation code
for each instance where the function is inlined. The resulting increase
in kernel code size can have negative impact:
- More cache misses in instruction cache
- Reduced amount of DMA-capable memory

Therefore change all functions implementing I/O instructions from inline
to normal functions.

Bloat-o-meter summary after change (using performance_defconfig):

add/remove: 24/2 grow/shrink: 4/39 up/down: 2205/-4858 (-2653)

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/cio: Introduce common I/O layer tracepoints

Add tracepoints to interrupt handler and core inline assemblies used by
the s390 common I/O layer. These tracepoints can be used to monitor and
valid

s390/cio: Introduce common I/O layer tracepoints

Add tracepoints to interrupt handler and core inline assemblies used by
the s390 common I/O layer. These tracepoints can be used to monitor and
validate hardware and hypervisor requests and responses.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/cio: add eadm subchannel driver

This driver allows usage of EADM subchannels. EADM subchannels
act as a communication vehicle for SCM increments.

Signed-off-by: Sebastian Ott <sebott@linux.vne

s390/cio: add eadm subchannel driver

This driver allows usage of EADM subchannels. EADM subchannels
act as a communication vehicle for SCM increments.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390: add scm bus driver

Bus driver to manage Storage Class Memory.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] qdio: convert global statistics to per-device stats

Revamp the qdio performance statistics and move them from procfs to
debugfs using the seq_file interface. Since the statistics are not
inte

[S390] qdio: convert global statistics to per-device stats

Revamp the qdio performance statistics and move them from procfs to
debugfs using the seq_file interface. Since the statistics are not
intended for the general user the removal of /proc/qdio_perf should
not surprise anyone.

The per device statistics are disabled by default, writing 1 to
/<debugfs mountpoint>/qdio/<device bus ID>/statistics enables the
statistics for the given device.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] cio: consistent infrastructure for internal I/O requests

Reduce code duplication by introducing a central infrastructure to
perform an internal I/O operation on a CCW device.

Signed-off-by:

[S390] cio: consistent infrastructure for internal I/O requests

Reduce code duplication by introducing a central infrastructure to
perform an internal I/O operation on a CCW device.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] cio: move scsw helper functions to header file

All scsw helper functions are very short and usage of them shouldn't
result in function calls. Therefore we move them to a separate header
file.

[S390] cio: move scsw helper functions to header file

All scsw helper functions are very short and usage of them shouldn't
result in function calls. Therefore we move them to a separate header
file.
Also saves a lot of EXPORT_SYMBOLs.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] split/move machine check handler code

Split machine check handler code and move it to cio and kernel code
where it belongs to. No functional change.

Signed-off-by: Heiko Carstens <heiko.cars

[S390] split/move machine check handler code

Split machine check handler code and move it to cio and kernel code
where it belongs to. No functional change.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] qdio: new qdio driver.

List of major changes:
- split qdio driver into several files
- seperation of thin interrupt code
- improved handling for multiple thin interrupt devices
- inbound and

[S390] qdio: new qdio driver.

List of major changes:
- split qdio driver into several files
- seperation of thin interrupt code
- improved handling for multiple thin interrupt devices
- inbound and outbound processing now always runs in tasklet context
- significant less tasklet schedules per interrupt needed
- merged qebsm with non-qebsm handling
- cleanup qdio interface and added kerneldoc
- coding style

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Utz Bacher <utz.bacher@de.ibm.com>
Reviewed-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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[S390] cio: Add chsc subchannel driver.

This patch adds a driver for subchannels of type chsc.

A device /dev/chsc is created which may be used to issue ioctls to:
- obtain information about the mac

[S390] cio: Add chsc subchannel driver.

This patch adds a driver for subchannels of type chsc.

A device /dev/chsc is created which may be used to issue ioctls to:
- obtain information about the machine's I/O configuration
- dynamically change the machine's I/O configuration via
asynchronous chsc commands

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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[S390] cio: introduce isc_(un)register functions.

This interface makes it easy for drivers to register usage of different
I/O interruption subclasses without needing to worry about possible
other us

[S390] cio: introduce isc_(un)register functions.

This interface makes it easy for drivers to register usage of different
I/O interruption subclasses without needing to worry about possible
other users of the same isc.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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[S390] cio: provide helper functions for fcx enabled I/O

Provide functions which can be used to incrementally construct fcx
enabled I/O control blocks.

Signed-off-by: Peter Oberparleiter <peter.obe

[S390] cio: provide helper functions for fcx enabled I/O

Provide functions which can be used to incrementally construct fcx
enabled I/O control blocks.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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[S390] cio: provide functions for fcx enabled I/O

Provide functions for assembling and starting fcx enabled I/O request
blocks.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
S

[S390] cio: provide functions for fcx enabled I/O

Provide functions for assembling and starting fcx enabled I/O request
blocks.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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[S390] cio: introduce fcx enabled scsw format

Extend the scsw data structure to the format required by fcx. Also
provide helper functions for easier access to fields which are present
in both the tr

[S390] cio: introduce fcx enabled scsw format

Extend the scsw data structure to the format required by fcx. Also
provide helper functions for easier access to fields which are present
in both the traditional as well as the modified format.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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