s390: add relocs tool

This 'relocs' tool is copied from the x86 version, ported for s390, and
greatly simplified to remove unnecessary features.

It reads vmlinux and outputs assembly to create a .vmlinux.relocs_64
section which contains the offsets of all R_390_64 relocations which
apply to allocatable sections.

Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Link: https://lore.kernel.org/r/20240219132734.22881-3-sumanthk@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

kbuild: rename hostprogs-y/always to hostprogs/always-y

In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

always -> always-y
hostprogs-y -> hostprogs

So, scripts/Makefile will look like this:

always-$(CONFIG_BUILD_BIN2C) += ...
always-$(CONFIG_KALLSYMS) += ...
...
hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

s390: drop meaningless 'targets' from tools Makefile

'targets' should be specified to include .*.cmd files to evaluate
if_changed or friends.

Here, facility-defs.h and dis-defs.h are generated by filechk.

Because filechk does not generate .*.cmd file, the 'targets' addition
is meaningless. The filechk correctly updates the target when its
content is changed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390: drop redundant directory creation from tools Makefile

As you can see in scripts/Kbuild.include, the filechk creates the
parent directory of the target as needed.

This Makefile does not need to explicitly create the directory.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390: drop unneeded -Wall addition from tools Makefile

The top level Makefile adds -Wall globally for all host tools:

KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \

I see two "-Wall" added for compiling these tools.

Of course, it is allowed to pass the same option multiple times, but
we do not need to do so.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

s390: do not pass $(LINUXINCLUDE) to gen_opcode_table.c

I guess HOSTCFLAGS_gen_opcode_table.o was blindly copied from
HOSTCFLAGS_gen_facilities.o

The reason of adding $(LINUXINCLUDE) to HOSTCFLAGS_gen_facilities.o
is because gen_facilities.c references some CONFIG options. (Kbuild
does not cater to this for host tools automatically.)

On the other hand, gen_opcode_table.c does not reference CONFIG
options at all. So, there is no good reason to pass $(LINUXINCLUDE).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

kbuild: use assignment instead of define ... endef for filechk_* rules

You do not have to use define ... endef for filechk_* rules.

For simple cases, the use of assignment looks cleaner, IMHO.

I updated the usage for scripts/Kbuild.include in case somebody
misunderstands the 'define ... endif' is the requirement.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>

kbuild: change filechk to surround the given command with { }

filechk_* rules often consist of multiple 'echo' lines. They must be
surrounded with { } or ( ) to work correctly. Otherwise, only the
string from the last 'echo' would be written into the target.

Let's take care of that in the 'filechk' in scripts/Kbuild.include
to clean up filechk_* rules.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

s390/tools: generate header files in arch/s390/include/generated/

Previously, the generated dis.h and facilities.h header files have been
stored in include/generated. Because they are s390 specific, store them
in the arch/s390/include/generated/asm/ directory. Also update
references to the header files respectively.

To prevent name collisions with those header files in asm/ that
include the generated ones, rename the generated headers files
and add an -defs suffix. Also update the generators to create
the ifdef guards respectively.

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

s390: remove unused parameter from Makefile

Remove unused parameter from the call function,
which I accidentally added.

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

s390/disassembler: generate opcode tables from text file

The current way of adding new instructions to the opcode tables is
painful and error prone. Therefore add, similar to binutils, a text
file which contains all opcodes and the corresponding mnemonics and
instruction formats.

A small gen_opcode_table tool then generates a header file with the
required enums and opcode table initializers at the prepare step of
the kernel build.

This way only a simple text file has to be maintained, which can be
rather easily extended.

Unlike before where there were plenty of opcode tables and a large
switch statement to find the correct opcode table, there is now only
one opcode table left which contains all instructions. A second opcode
offset table now contains offsets within the opcode table to find
instructions which have the same opcode prefix. In order to save space
all 1-byte opcode instructions are grouped together at the end of the
opcode table. This is also quite similar to like it was before.

In addition also move and change code and definitions within the
disassembler. As a side effect this reduces the size required for the
code and opcode tables by ~1.5k.

Signed-off-by: Heiko Carstens <heiko.carstens@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: remove unneeded dependency for gen_facilities

The dependency between the object and the source is handled by
scripts/Makefile.host, so only "hostprogs-y += gen_facilities"
is fine.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/facilities: add helper tool to generate facility lists

Modifying the architecture level set facility lists was always very
error prone. Given the numbering of the facility bits within the
Principles of Operation, where the most significant bit number is 0,
it happened a lot of times that wrong bits were set or cleared.

Therefore this patch adds a tool "gen_facilities" which generates
include/generated/facilites.h. The definition of the bits to be set
is contained within arch/s390/include/asm/facilities_src.h and can be
easily extended to e.g. also generate such lists for the KVM module.

The generated file looks like this:

#define FACILITIES_ALS _AC(0xc1006450f0040000,UL)
#define FACILITIES_ALS_DWORDS 1

The facility bits defined in this patch match 1:1 to the current masks
that can be found in head.S.

That is if the tool gets executed with -march=z990 then the generated
masks will equal the masks in head.S for CONFIG_MARCH_Z990.

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