asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch

Now we specify the minimal version of GCC as 5.1 and Clang/LLVM as 11.0.0
in Documentation/process/changes.rst, __CHAR_BIT__ and __SIZEOF_LONG__ are
usable, it is probably fine to unify the definition of __BITS_PER_LONG as
(__CHAR_BIT__ * __SIZEOF_LONG__) in asm-generic uapi bitsperlong.h.

In order to keep safe and avoid regression, only unify uapi bitsperlong.h
for some archs such as arm64, riscv and loongarch which are using newer
toolchains that have the definitions of __CHAR_BIT__ and __SIZEOF_LONG__.

Suggested-by: Xi Ruoyao <xry111@xry111.site>
Link: https://lore.kernel.org/all/d3e255e4746de44c9903c4433616d44ffcf18d1b.camel@xry111.site/
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/linux-arch/a3a4f48a-07d4-4ed9-bc53-5d383428bdd2@app.fastmail.com/
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

LoongArch: Add other common headers

Add some other common headers for basic LoongArch support.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

tools headers: Fixup bitsperlong per arch includes

We were getting the file by luck, from one of the paths in -I, fix it to
get it from the proper place:

$ cd tools/include/uapi/asm/
[acme@quaco asm]$ grep include bitsperlong.h
#include "../../arch/x86/include/uapi/asm/bitsperlong.h"
#include "../../arch/arm64/include/uapi/asm/bitsperlong.h"
#include "../../arch/powerpc/include/uapi/asm/bitsperlong.h"
#include "../../arch/s390/include/uapi/asm/bitsperlong.h"
#include "../../arch/sparc/include/uapi/asm/bitsperlong.h"
#include "../../arch/mips/include/uapi/asm/bitsperlong.h"
#include "../../arch/ia64/include/uapi/asm/bitsperlong.h"
#include "../../arch/riscv/include/uapi/asm/bitsperlong.h"
#include "../../arch/alpha/include/uapi/asm/bitsperlong.h"
#include <asm-generic/bitsperlong.h>
$ ls -la ../../arch/x86/include/uapi/asm/bitsperlong.h
ls: cannot access '../../arch/x86/include/uapi/asm/bitsperlong.h': No such file or directory
$ ls -la ../../../arch/*/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 237 ../../../arch/alpha/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 841 ../../../arch/arm64/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 966 ../../../arch/hexagon/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 234 ../../../arch/ia64/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 100 ../../../arch/microblaze/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 244 ../../../arch/mips/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 352 ../../../arch/parisc/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 312 ../../../arch/powerpc/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 353 ../../../arch/riscv/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 292 ../../../arch/s390/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 323 ../../../arch/sparc/include/uapi/asm/bitsperlong.h
-rw-rw-r--. 1 320 ../../../arch/x86/include/uapi/asm/bitsperlong.h
$

Found while fixing some other problem, before it was escaping the
tools/ chroot and using stuff in the kernel sources:

CC /tmp/build/perf/util/find_bit.o
In file included from /git/linux/tools/include/../../arch/x86/include/uapi/asm/bitsperlong.h:11,
from /git/linux/tools/include/uapi/asm/bitsperlong.h:3,
from /git/linux/tools/include/linux/bits.h:6,
from /git/linux/tools/include/linux/bitops.h:13,
from ../lib/find_bit.c:17:

# cd /git/linux/tools/include/../../arch/x86/include/uapi/asm/
# pwd
/git/linux/arch/x86/include/uapi/asm
#

Now it is getting the one we want it to, i.e. the one inside tools/:

CC /tmp/build/perf/util/find_bit.o
In file included from /git/linux/tools/arch/x86/include/uapi/asm/bitsperlong.h:11,
from /git/linux/tools/include/linux/bits.h:6,
from /git/linux/tools/include/linux/bitops.h:13,

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-8f8cfqywmf6jk8a3ucr0ixhu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools uapi: fix Alpha support

Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Bob Tracy <rct@frus.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

tools uapi: fix RISC-V 64-bit support

The BPF library is not built on 64-bit RISC-V, as the BPF feature is
not detected. Looking more in details, feature/test-bpf.c fails to build
with the following error:

| In file included from /tmp/linux-4.19.12/tools/include/uapi/asm/bitsperlong.h:17,
| from /tmp/linux-4.19.12/tools/include/uapi/asm-generic/unistd.h:2,
| from /usr/include/riscv64-linux-gnu/asm/unistd.h:1,
| from test-bpf.c:2:
| /tmp/linux-4.19.12/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h
| #error Inconsistent word size. Check asm/bitsperlong.h
| ^~~~~

The UAPI from the tools directory is missing RISC-V support, therefore
bitsperlong.h from asm-generic is used, defaulting to 32 bits.

Fix that by adding tools/arch/riscv/include/uapi/asm/bitsperlong.h as
a copy of arch/riscv/include/uapi/asm/bitsperlong.h and by updating
tools/include/uapi/asm/bitsperlong.h.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

selftests/bpf: add architecture-agnostic headers

The BPF selftests fail to build with missing headers
'asm/bitsperlong.h' and 'asm/errno.h'.

These already exist in 'tools/arch/[arch]/include';
add architecture-agnostic header files in 'tools/include/uapi'
to reference them.

Signed-off-by: Sirio Balmelli <sirio@b-ad.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>