RISC-V: Add a syscall for HW probing

We don't have enough space for these all in ELF_HWCAP{,2} and there's no
system call that quite does this, so let's just provide an arch-specific
one to probe for hardware capabilities. This currently just provides
m{arch,imp,vendor}id, but with the key-value pairs we can pass more in
the future.

Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Evan Green <evan@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-3-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

riscv: Wire up memfd_secret in UAPI header

Move the __ARCH_WANT_MEMFD_SECRET define added in commit 7bb7f2ac24a0
("arch, mm: wire up memfd_secret system call where relevant") to
<uapi/asm/unistd.h> so __NR_memfd_secret is defined when including
<unistd.h> in userspace.

This allows the memfd_secret selftest to pass on riscv.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Link: https://lore.kernel.org/r/20220505081815.22808-1-tklauser@distanz.ch
Fixes: 7bb7f2ac24a0 ("arch, mm: wire up memfd_secret system call where relevant")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

riscv: compat: syscall: Add compat_sys_call_table implementation

Implement compat sys_call_table and some system call functions:
truncate64, ftruncate64, fallocate, pread64, pwrite64,
sync_file_range, readahead, fadvise64_64 which need argument
translation.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20220405071314.3225832-12-guoren@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

RISC-V: Include clone3() on rv32

As far as I can tell this should be enabled on rv32 as well, I'm not
sure why it's rv64-only. checksyscalls is complaining about our lack of
clone3() on rv32.

Fixes: 56ac5e213933 ("riscv: enable sys_clone3 syscall for rv64")
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Replace HTTP links with HTTPS ones: RISC-V

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

riscv: enable sys_clone3 syscall for rv64

Enable the sys_clone3 syscall for RV64. We simply include the generic
version.

Tested by running the program from

https://lore.kernel.org/lkml/20190716130631.tohj4ub54md25dys@brauner.io/

and verifying that it completes successfully.

Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Acked-by: Christian Brauner <christian@brauner.io>
Cc: Christian Brauner <christian@brauner.io>

riscv: Use latest system call ABI

We don't yet have an upstream glibc port for riscv, so there is no user
space for the existing ABI, and we can remove the definitions for 32-bit
time_t, off_t and struct resource and system calls based on them,
including the vdso.

Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

asm-generic: Make time32 syscall numbers optional

We don't want new architectures to even provide the old 32-bit time_t
based system calls any more, or define the syscall number macros.

Add a new __ARCH_WANT_TIME32_SYSCALLS macro that gets enabled for all
existing 32-bit architectures using the generic system call table,
so we don't change any current behavior.
Since this symbol is evaluated in user space as well, we cannot use
a Kconfig CONFIG_* macro but have to define it in uapi/asm/unistd.h.

On 64-bit architectures, the same system call numbers mostly refer to
the system calls we want to keep, as they already pass 64-bit time_t.

As new architectures no longer provide these, we need new exceptions
in checksyscalls.sh.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

asm-generic: Drop getrlimit and setrlimit syscalls from default list

The newer prlimit64 syscall provides all the functionality of getrlimit
and setrlimit syscalls and adds the pid of target process, so future
architectures won't need to include getrlimit and setrlimit.

Therefore drop getrlimit and setrlimit syscalls from the generic syscall
list unless __ARCH_WANT_SET_GET_RLIMIT is defined by the architecture's
unistd.h prior to including asm-generic/unistd.h, and adjust all
architectures using the generic syscall list to define it so that no
in-tree architectures are affected.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-hexagon@vger.kernel.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Salter <msalter@redhat.com> [c6x]
Acked-by: James Hogan <james.hogan@imgtec.com> [metag]
Acked-by: Ley Foon Tan <lftan@altera.com> [nios2]
Acked-by: Stafford Horne <shorne@gmail.com> [openrisc]
Acked-by: Will Deacon <will.deacon@arm.com> [arm64]
Acked-by: Vineet Gupta <vgupta@synopsys.com> #arch/arc bits
Signed-off-by: Yury Norov <ynorov@marvell.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

riscv: add asm/unistd.h UAPI header

Marcin Juszkiewicz reported issues while generating syscall table for riscv
using 4.20-rc1. The patch refactors our unistd.h files to match some other
architectures.

- Add asm/unistd.h UAPI header, which has __ARCH_WANT_NEW_STAT only for 64-bit
- Remove asm/syscalls.h UAPI header and merge to asm/unistd.h
- Adjust kernel asm/unistd.h

So now asm/unistd.h UAPI header should show all syscalls for riscv.

Before this, Makefile simply put `#include <asm-generic/unistd.h>` into
generated asm/unistd.h UAPI header thus user didn't see:

- __NR_riscv_flush_icache
- __NR_newfstatat
- __NR_fstat

which are supported by riscv kernel.

Signed-off-by: David Abdurachmanov <david.abdurachmanov@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Fixes: 67314ec7b025 ("RISC-V: Request newstat syscalls")
Signed-off-by: David Abdurachmanov <david.abdurachmanov@gmail.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>