s390: add support for user-defined certificates

Enable receiving the user-defined certificates from the s390x
hypervisor via new diagnose 0x320 calls, and make them available to the
Linux root user as 'cert_store_key' type keys in a so-called
'cert_store' keyring.

New user-space interfaces:

/sys/firmware/cert_store/refresh

Writing to this attribute re-fetches certificates via DIAG 0x320

/sys/firmware/cert_store/cs_status

Reading from this attribute returns either of:

"uninitialized"
If no certificate has been retrieved yet
"ok"
If certificates have been successfully retrieved
"failed (<number>)"
If certificate retrieval failed with reason code <number>

New debug trace areas:

/sys/kernel/debug/s390dbf/cert_store_msg

/sys/kernel/debug/s390dbf/cert_store_hexdump

Usage example:

To initiate request for certificates available to the system as root:

$ echo 1 > /sys/firmware/cert_store/refresh

Upon success the '/sys/firmware/cert_store/cs_status' contains
the value 'ok'.

$ cat /sys/firmware/cert_store/cs_status
ok

Get the ID of the keyring 'cert_store':

$ keyctl search @us keyring cert_store
OR
$ keyctl link @us @s; keyctl request keyring cert_store

Obtain list of IDs of certificates:

$ keyctl rlist <cert_store keyring ID>

Display certificate content as hex-dump:

$ keyctl read <certificate ID>

Read certificate contents as binary data:

$ keyctl pipe <certificate ID> >cert_data

Display certificate description:

$ keyctl describe <certificate ID>

The certificate description has the following format:

<64 bytes certificate name in EBCDIC> ':'
<certificate index as obtained from hypervisor> ':'
<certificate store token obtained from hypervisor>

The certificate description in /proc/keys has certificate name
represented in ASCII.

Users can read but cannot update the content of the certificate.

Signed-off-by: Anastasia Eskova <anastasia.eskova@ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/sclp: introduce sclp_emergency_printk()

Introduce sclp_emergency_printk() which can be used to emit a message
in emergency cases. sclp_emergency_printk() is only supposed to be
used in cases where it can be assumed that regular console device
drivers may not work anymore.
For example this may be the case for unrecoverable machine checks.

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/ipl: add eckd support

This adds support to IPL from ECKD DASDs to linux.
It introduces a few sysfs files in /sys/firmware/reipl/eckd:

bootprog: the boot program selector
clear: whether to issue a diag308 LOAD_NORMAL or LOAD_CLEAR
device: the device to ipl from
br_chr: Cylinder/Head/Record number to read the bootrecord from.
Might be '0' or 'auto' if it should be read from the
volume label.
scpdata: data to be passed to the ipl'd program.

The new ipl type is called 'eckd'.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/crash: support multi-segment iterators

Make it possible to handle not only single-, but also multi-
segment iterators in copy_oldmem_iter() callback. Change the
semantics of called functions to match the iterator model -
instead of an error code the exact number of bytes copied is
returned.

The swap page used to copy data to user space is adopted for
kernel space too. That does not bring any performance impact.

Suggested-by: Matthew Wilcox <willy@infradead.org>
Fixes: cc02e6e21aa5 ("s390/crash: add missing iterator advance in copy_oldmem_page()")
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Link: https://lore.kernel.org/r/5af6da3a0bffe48a90b0b7139ecf6a818b2d18e8.1658206891.git.agordeev@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/sclp: detect the AISI facility

Detect the Adapter Interruption Suppression Interpretation facility.

Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-5-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

s390/sclp: detect the AENI facility

Detect the Adapter Event Notification Interpretation facility.

Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-4-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

s390/sclp: detect the AISII facility

Detect the Adapter Interruption Source ID Interpretation facility.

Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-3-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

s390/sclp: detect the zPCI load/store interpretation facility

Detect the zPCI Load/Store Interpretation facility.

Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-2-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

s390/sclp: add detection of IPL-complete-control facility

The presence of the IPL-complete-control facility can be derived
from the hypervisor's SCLP info response.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390: remove invalid email address of Heiko Carstens

Remove my old invalid email address which can be found in a couple of
files. Instead of updating it, just remove my contact data completely
from source files.
We have git and other tools which allow to figure out who is responsible
for what with recent contact data.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

treewide: Replace zero-length arrays with flexible-array members

There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].

This code was transformed with the help of Coccinelle:
(next-20220214$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)

@@
identifier S, member, array;
type T1, T2;
@@

struct S {
...
T1 member;
T2 array[
- 0
];
};

UAPI and wireless changes were intentionally excluded from this patch
and will be sent out separately.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/78
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

s390/sclp: sort out physical vs virtual pointers usage

Provide physical addresses whenever the hardware interface
expects it or a 32-bit value used for tracking.

Variable sclp_early_sccb gets initialized in the decompressor
and points to an address in physcal memory. Yet, it is used
as virtual memory pointer and therefore should be converted.

Note, the other two __bootdata variables sclp_info_sccb and
sclp_info_sccb_valid contain plain data, but no pointers and
do need any special care.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/sclp: reserve memory occupied by sclp early buffer

The memory block occupied by the SCLP early buffer that is allocated
by the decompressor and then handed over to the decompressed kernel,
must be reserved to prevent it from being reused for other purposes.
This is necessary because the SCLP early buffer is still in use
during kernel initialization.

Fixes: f1d3c5323772 ("s390/boot: move sclp early buffer from fixed address in asm to C")
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reported-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/boot: move sclp early buffer from fixed address in asm to C

To make the decompressor relocatable, the early SCLP buffer with a fixed
address must be replaced with a relocatable C buffer of the according size
and alignment as required by SCLP.

Introduce a new function sclp_early_set_buffer() into the SCLP driver
which enables the decompressor to change the SCLP early buffer at any time.
This will be useful when the decompressor becomes fully relocatable and
might need to change the SCLP early buffer to one with an address < 2G
as required by SCLP because it was loaded at an address >= 2G.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/sclp: use only one sclp early buffer to send commands

A buffer that can be used for communication with SCLP is required
to lie below 2GB memory address. Therefore, both sclp_info_sccb
and sclp_early_sccb must fulfill this requirement if passed directly
to the sclp_early_cmd() function. Instead, use only sclp_early_sccb
for communication with SCLP. This allows the buffer sclp_info_sccb
to be placed anywhere in the memory address space and, therefore,
simplifies the process of making the decompressor relocatable later on,
one thing less to relocate. And make sure that the length of the new unified
early SCLP buffer is no less than the length of the removed sclp_info_sccb
buffer which might be larger than the length of the sclp_early_sccb buffer.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/sclp: provide extended sccb support

As the number of cpus increases, the sccb response can exceed 4k for
read cpu and read scp info sclp commands. Hence, all cpu info entries
cant be embedded within a sccb response

Solution:
To overcome this limitation, extended sccb facility is provided by sclp.

1. Check if the extended sccb facility is installed.
2. If extended sccb is installed, perform the read scp and read cpu
command considering a max sccb length of three page size. This max
length is based on factors like max cpus, sccb header.
3. If extended sccb is not installed, perform the read scp and read cpu
sclp command considering a max sccb length of one page size.

Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/sclp: Add support for SCLP AP adapter config/deconfig

Add support for AP bus adapter config and deconfig to the sclp
core code. The code is statically build into the kernel when
ZCRYPT is configured either as module or with static support.

This is the base functionality for having configure/deconfigure
support in the AP bus and card code. Another patch will exploit
this soon.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Suggested-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/sclp: remove unused sclp_early_printk_forced

This reverts commit 55a5542a5462 ("s390/hibernate: fix error handling when
suspend cpu != resume cpu"). It added sclp_early_printk_force() which
is no longer used since commit 394216275c7d ("s390: remove broken
hibernate / power management support"). No hibernate - no problem.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/ipl: Fix detection of has_secure attribute

Use the correct bit for detection of the machine capability associated
with the has_secure attribute. It is expected that the underlying
platform (including hypervisors) unsets the bit when they don't provide
secure ipl for their guests.

Fixes: c9896acc7851 ("s390/ipl: Provide has_secure sysfs attribute")
Cc: stable@vger.kernel.org # 5.2
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/sclp: detect DIRQ facility

Detect the adapter CPU directed interruption facility.

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

s390/ipl: Provide has_secure sysfs attribute

Provide an interface for userspace so it can find out if a machine is
capeable of doing secure boot. The interface is, for example, needed for
zipl so it can find out which file format it can/should write to disk.

Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/setup: set control program code via diag 318

The s390x diagnose 318 instruction sets the control program name code (CPNC)
and control program version code (CPVC) to provide useful information
regarding the OS during debugging. The CPNC is explicitly set to 4 to
indicate a Linux/KVM environment.

The CPVC is a 7-byte value containing:

- 3-byte Linux version code, currently set to 0
- 3-byte unique value, currently set to 0
- 1-byte trailing null

Signed-off-by: Collin Walling <walling@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <1544135405-22385-2-git-send-email-walling@linux.ibm.com>
[set version code to 0 until the structure is fully defined]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: introduce sclp_early_get_hsa_size

Introduce sclp_early_get_hsa_size function to be used during early
memory detection. This function allows to find a memory limit imposed
during zfcpdump.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/mem_detect: replace tprot loop with binary search

In a situation when other memory detection methods are not available
(no SCLP and no z/VM diag260), continuous online memory is assumed.
Replacing tprot loop with faster binary search, as only online memory
end has to be found.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/mem_detect: introduce SCLP storage info

SCLP storage info allows to detect continuous and non-continuous online
memory under LPAR, z/VM and KVM, when standby memory is defined.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/mem_detect: move tprot loop to early boot phase

Move memory detection to early boot phase. To store online memory
regions "struct mem_detect_info" has been introduced together with
for_each_mem_detect_block iterator. mem_detect_info is later converted
to memblock.

Also introduces sclp_early_get_meminfo function to get maximum physical
memory and maximum increment number.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: move sclp_early_read_info to sclp_early_core.c

To enable early online memory detection sclp_early_read_info has
been moved to sclp_early_core.c. sclp_info_sccb has been made a part
of .boot.data, which allows to reuse it later during early kernel
startup and make sclp_early_read_info call just once.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: Allow to request adapter reset

The SCLP event 24 "Adapter Error Notification" supports three different
action qualifier of which 'adapter reset' is currently not enabled in
the sysfs interface. However, userspace tools might want to be able
to use the reset functionality as well. Enable the 'adapter reset'
qualifier.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/hibernate: fix error handling when suspend cpu != resume cpu

The resume code checks if the resume cpu is the same as the suspend cpu.
If not, and if it is also not possible to switch to the suspend cpu, an
error message should be printed and the resume process should be stopped
by loading a disabled wait psw.

The current logic is broken in multiple ways, the message is never printed,
and the disabled wait psw never loaded because the kernel panics before that:
- sam31 and SIGP_SET_ARCHITECTURE to ESA mode is wrong, this will break
on the first 64bit instruction in sclp_early_printk().
- The init stack should be used, but the stack pointer is not set up correctly
(missing aghi %r15,-STACK_FRAME_OVERHEAD).
- __sclp_early_printk() checks the sclp_init_state. If it is not
sclp_init_state_uninitialized, it simply returns w/o printing anything.
In the resumed kernel however, sclp_init_state will never be uninitialized.

This patch fixes those issues by removing the sam31/ESA logic, adding a
correct init stack pointer, and also introducing sclp_early_printk_force()
to allow using sclp_early_printk() even when sclp_init_state is not
uninitialized.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: expose the GISA format facility

The GISA format facility is required by the host to be able to process
a format-1 GISA. If not available, the used GISA format will be format-0.
All format-1 related extension will not be available in this case.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

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>

s390/sclp: Detect KSS facility

Let's detect the keyless subset facility.

Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: make early sclp code readable

This patch

- unifies the old sclp early code and the sclp early printk code, so
they can use common functions

- makes sure all sclp early functions and variables have the same
"sclp_early" prefix

- converts the sclp early printk code into readable code by using
existing data structures instead of hard coded magic arrays

- splits the early sclp code into two files: sclp_early.c and
sclp_early_core.c. The core file contains everything that is
required by the kernel decompressor and may not call functions not
contained within the core file. Otherwise the result would be a
link error.

- changes interrupt handling to be completely synchronous. The old
early sclp code had a small window which allowed to receive several
interrupts instead of exactly the single expected interrupt. This
did hide a subtle potential bug, which is fixed with this large
rework.

- contains a couple of small cleanups.

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390: provide sclp based boot console

Use the early sclp code to provide a boot console. This boot console
is available if the kernel parameter "earlyprintk" has been specified,
just like it works for other architectures that also provide an early
boot console.

This makes debugging of early problems much easier, since now we
finally have working console output even before memory detection is
running.

The boot console will be automatically disabled as soon as another
console will be registered.

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/smp: initialize cpu_present_mask in setup_arch

In order to be able to setup the cpu to node mappings early it is a
prerequisite to know which cpus are present. Therefore cpus must be
detected much earlier than before.

For sclp based cpu detection this requires yet another early sclp
call, since the system is not ready to use the regular interrupt and
memory allocations.

Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: detect storage-key facility

Let's correctly detect that facility.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect interlock-and-broadcast-suppression facility

Let's detect that facility.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect PFMF interpretation facility

Let's detect that facility.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect conditional-external-interception facility

Let's detect if we have that facility.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect intervention bypass facility

Let's detect if we have the intervention bypass facility installed.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect guest-storage-limit-suppression

Let's detect that facility.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect cmma

Let's detect the Collaborative-memory-management-interpretation facility,
aka CMM assist, so we can correctly enable cmma later.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect guest-PER enhancement

Let's detect that facility, so we can correctly handle its abscence.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: detect 64-bit-SCAO facility

Let's correctly detect that facility, so we can correctly handle its
abscence later on.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390: Make cpc_name accessible

sclp_ocf.c is the only way to get the cpc name, as it registers the
sole event handler for the ocf event. By creating a new global
function that copies that name, we make it accessible to the world
which longs to retrieve it.

Additionally we now also store the cpc name as EBCDIC, so we don't
have to convert it to and from ASCII if it is requested in native
encoding.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: Add hmfai field

Let's add hypervisor-managed facility-apportionment indications field to
SCLP structs. KVM will use it to reduce maintenance cost of
Non-Hypervisor-Managed facility bits.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: add error notification command

Add SCLP event 24 "Adapter-error notification".

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

s390/mem_detect: use unsigned longs

The memory detection code historically had to use unsigned long long
since the machine reported the true memory size (>4GB) even if the
virtual machine was running in ESA/390 mode.

Since the old code is gone use unsigned long everywhere and also get
rid of an unused ADDR2G define.

(this patch converts all long longs within sclp_info to longs)

There are many more possible conversions, however that can be done if
somebody touches the corresponding code. Since people started to
convert unrelated long types to long longs because of the types within
struct sclp_info convert this now.

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

s390/sclp: introduce check for SIE

This patch adds a way to check if the SIE with zArchitecture support is
available.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: introduce checks for ESCA and HVS

Introduce sclp.has_hvs and sclp.has_esca to provide a way for kvm to check
whether the extended-SCA and the home-virtual-SCA facilities are available.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/sclp: Add VT220 support to early sclp console

When running under qemu with the default configuration (-nographic),
there is only a VT220 SCLP console, no line-mode SCLP console. Add
VT220 support to the early SCLP console so the user has a chance to
see critical error messages during early boot.

None of the existing users of _sclp_print_early() check the return
code. Instead of trying to come up with return code semantics when
printing to multiple consoles (any or all of which may fail), we just
drop the return code entirely.

Tested on z/VM (line mode console) and LPAR (VT220 and line mode
console). Tested on qemu/KVM with VT220 console and / or line mode
console.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dump: streamline oldmem copy functions

Introduce two copy functions for the memory of the dumped system,
copy_oldmem_kernel() to copy to the virtual kernel address space
and copy_oldmem_user() to copy to user space.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: convert early sclp console code to C

The 31-bit assembler code for the early sclp console is error
prone as git commit fde24b54d976cc123506695c17db01438a11b673
"s390/sclp: clear upper register halves in _sclp_print_early"
has shown.

Convert the assembler code to C.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/smp: cleanup core vs. cpu in the SCLP interface

The SCLP interface to query, configure and deconfigure CPUs actually
operates on cores. For a machine without the multi-threading faciltiy
a CPU and a core are equivalent but starting with System z13 a core
can have multiple hardware threads, also referred to as logical CPUs.

To avoid confusion replace the word 'cpu' with 'core' in the SCLP
interface. Also replace MAX_CPU_ADDRESS with SCLP_MAX_CORES.
The core-id is an 8-bit field, the maximum thread id is in the range
0-31. The theoretical limit for the CPU address is therefore 8191.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: move sclp_facilities into "struct sclp"

Let's also move the facilities into the sclp struct, so we can avoid
another separate external variable.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: get rid of sclp_get_mtid() and sclp_get_mtid_max()

As all relevant sclp data is now directly accessible, let's move the
logic of these two functions to the single caller.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: unify basic sclp access by exposing "struct sclp"

Let's unify basic access to sclp fields by storing the data in an external
struct in asm/sclp.h.

The values can now directly be accessed by other components, so there is
no need for most accessor functions and external variables anymore.

The mtid, mtid_max and facility part will be cleaned up separately.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: introduce check for the SIGP Interpretation Facility

This patch introduces the infrastructure to check whether the SIGP
Interpretation Facility is installed on all VCPUs in the configuration.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390: add SMT support

The multi-threading facility is introduced with the z13 processor family.
This patch adds code to detect the multi-threading facility. With the
facility enabled each core will surface multiple hardware threads to the
system. Each hardware threads looks like a normal CPU to the operating
system with all its registers and properties.

The SCLP interface reports the SMT topology indirectly via the maximum
thread id. Each reported CPU in the result of a read-scp-information
is a core representing a number of hardware threads.

To reflect the reduced CPU capacity if two hardware threads run on a
single core the MT utilization counter set is used to normalize the
raw cputime obtained by the CPU timer deltas. This scaled cputime is
reported via the taskstats interface. The normal /proc/stat numbers
are based on the raw cputime and are not affected by the normalization.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: fix declaration of _sclp_print_early()

_sclp_print_early() has return value: at present, return 0 for OK, 1 for
failure. It returns '%r2', so use 'long' as return value (upper caller
can check '%r2' directly). The related warning:

CC arch/s390/boot/compressed/misc.o
arch/s390/boot/compressed/misc.c:66:8: warning: type defaults to 'int' in declaration of '_sclp_print_early' [-Wimplicit-int]
extern _sclp_print_early(const char *);
^

At present, _sclp_print_early() is only used by puts(), so can still
remain its declaration in 'misc.c' file.

[heiko.carstens@de.ibm.com]: move declaration to sclp.h header file

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: add sclp_get_ibc function

The patch adds functionality to retrieve the IBC configuration
by means of function sclp_get_ibc().

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

KVM: s390/sclp: correctly set eca siif bit

Check if siif is available before setting.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

s390/smp: limit number of cpus in possible cpu mask

Limit the number of bits to the maximum number of cpus a machine
can have.
possible_cpu_mask typically will have more bits set than a machine
may physically have. This results in wasted memory during per-cpu
memory allocations, if the possible mask contains more cpus than
physically possible for a given configuration.

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

s390/hypfs: add interface for diagnose 0x304

To provide access to the set-partition-resource-parameter interface
to user space add a new attribute to hypfs/debugfs:
* s390_hypsfs/diag_304
The data for the query-partition-resource-parameters command can
be access by a read on the attribute. All other diagnose 0x304
requests need to be submitted via ioctl with CAP_SYS_ADMIN rights.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp_early: Add function to detect sclp console capabilities

Add SCLP console detect functions to encapsulate detection of SCLP console
capabilities, for example, VT220 support. Reuse the sclp_send/receive masks
that were stored by the most recent sclp_set_event_mask() call to prevent
unnecessary SCLP calls.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/smp,sclp: fix size of sclp_cpu_info structure

struct sclp_cpu_info contains entries only for 255 cpus, while the new
smp fallback sigp detection code will fill up to 256 entries.
Even though there is no machine available which has 256 cpus and where
in addition the fallback sigp cpu detection code will be used we better
fix this, to prevent out of bound accesses.

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

s390/sclp: Consolidate early sclp init calls to sclp_early_detect()

The new function calls the old ones. The sclp_event_mask_early() is removed
and replaced by one invocation of sclp_set_event_mask(0, 0).

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/sclp: Determine HSA size dynamically for zfcpdump

Currently we have hardcoded the HSA size to 32 MiB. With this patch the
HSA size is determined dynamically via SCLP in early.c.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/vmcore: use vmcore for zfcpdump

Modify the s390 copy_oldmem_page() and remap_oldmem_pfn_range() function
for zfcpdump to read from the HSA memory if memory below HSA_SIZE bytes is
requested. Otherwise real memory is used.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Willeke <willeke@de.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

s390/mm: implement software dirty bits

The s390 architecture is unique in respect to dirty page detection,
it uses the change bit in the per-page storage key to track page
modifications. All other architectures track dirty bits by means
of page table entries. This property of s390 has caused numerous
problems in the past, e.g. see git commit ef5d437f71afdf4a
"mm: fix XFS oops due to dirty pages without buffers on s390".

To avoid future issues in regard to per-page dirty bits convert
s390 to a fault based software dirty bit detection mechanism. All
user page table entries which are marked as clean will be hardware
read-only, even if the pte is supposed to be writable. A write by
the user process will trigger a protection fault which will cause
the user pte to be marked as dirty and the hardware read-only bit
is removed.

With this change the dirty bit in the storage key is irrelevant
for Linux as a host, but the storage key is still required for
KVM guests. The effect is that page_test_and_clear_dirty and the
related code can be removed. The referenced bit in the storage
key is still used by the page_test_and_clear_young primitive to
provide page age information.

For page cache pages of mappings with mapping_cap_account_dirty
there will not be any change in behavior as the dirty bit tracking
already uses read-only ptes to control the amount of dirty pages.
Only for swap cache pages and pages of mappings without
mapping_cap_account_dirty there can be additional protection faults.
To avoid an excessive number of additional faults the mk_pte
primitive checks for PageDirty if the pgprot value allows for writes
and pre-dirties the pte. That avoids all additional faults for
tmpfs and shmem pages until these pages are added to the swap cache.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/pci: PCI hotplug support via SCLP

Add SCLP PCI configure/deconfigure and implement a PCI hotplug
controller (s390_pci_hpc). The hotplug controller creates a slot
for every PCI function in stand-by or configured state. The PCI
functions are named after the PCI function ID (fid). By writing to
the power attribute in /sys/bus/pci/slots/<fid>/power the PCI function
is moved to stand-by or configured state. If moved to the configured
state the device is automatically scanned by the s390 PCI layer.

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

s390/comments: unify copyright messages and remove file names

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: Heiko Carstens <heiko.carstens@de.ibm.com>

KVM: s390: Perform early event mask processing during boot

For processing under KVM it is required to detect
the actual SCLP console type in order to set it as
preferred console.

Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

KVM: s390: add capability indicating COW support

Currently qemu/kvm on s390 uses a guest mapping that does not
allow the guest backing page table to be write-protected to
support older systems. On those older systems a host write
protection fault will be delivered to the guest.

Newer systems allow to write-protect the guest backing memory
and let the fault be delivered to the host, thus allowing COW.

Use a capability bit to tell qemu if that is possible.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

[S390] move include/asm-s390 to arch/s390/include/asm

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>