[PATCH v4 00/10] tools/nolibc: add a new syscall helper

[Zhangjin Wu]

Hi, Thomas, David, Willy

Thanks very much for your kindly review.

This is the revision of v3 "tools/nolibc: add a new syscall helper" [1],
this mainly applies the suggestion from David in this reply [2] and
rebased everything on the dev.2023.06.14a branch of linux-rcu [3].

The old __sysret() doesn't support the syscalls with pointer return
value, this revision now supports such syscalls. The left mmap() syscall
is converted to use this new __sysret() with additional test cases.

Changes from v3 -> v4:

* tools/nolibc: sys.h: add a syscall return helper
  tools/nolibc: unistd.h: apply __sysret() helper
  tools/nolibc: sys.h: apply __sysret() helper

  The original v3 series, no code change, except the Reviewed-by lines
  from Thomas.

* tools/nolibc: unistd.h: reorder the syscall macros

  reorder the syscall macros in using order and align most of them.

* tools/nolibc: add missing my_syscall6() for mips

  required by mmap() syscall, this is the last missing my_syscall6().

* tools/nolibc: __sysret: support syscalls who return a pointer

  Apply suggestion from David.  

  Let __sysret() also supports syscalls with pointer return value, so, the
  return value is converted to unsigned long and the comparing of < 0 is
  converted to the comparing of [(unsigned long)-MAX_ERRNO, (unsigned long)-1].

  This also allows return a huge value (not pointer) with highest bit as 1.

  It is able to merge this one to the first one if necessary.

* tools/nolibc: clean up mmap() support

  Apply new __sysret(), clean up #ifdef and some macros.

* selftests/nolibc: add EXPECT_PTREQ, EXPECT_PTRNE and EXPECT_PTRER
  selftests/nolibc: add sbrk_0 to test current brk getting
  selftests/nolibc: add mmap and munmap test cases

  Add some mmap & munmap test cases and the corresponding helpers, to
  verify one of the new helpers, a sbrk_0 test case is also added.

Best regards,
Zhangjin
---
[1]: https://lore.kernel.org/linux-riscv/87e7a391-b97b-4001-b12a-76d20790563e@t-8ch.de/
[2]: https://lore.kernel.org/linux-riscv/94dd5170929f454fbc0a10a2eb3b108d@AcuMS.aculab.com/
[3]: https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/

Zhangjin Wu (10):
  tools/nolibc: sys.h: add a syscall return helper
  tools/nolibc: unistd.h: apply __sysret() helper
  tools/nolibc: sys.h: apply __sysret() helper
  tools/nolibc: unistd.h: reorder the syscall macros
  tools/nolibc: add missing my_syscall6() for mips
  tools/nolibc: __sysret: support syscalls who return a pointer
  tools/nolibc: clean up mmap() support
  selftests/nolibc: add EXPECT_PTREQ, EXPECT_PTRNE and EXPECT_PTRER
  selftests/nolibc: add sbrk_0 to test current brk getting
  selftests/nolibc: add mmap and munmap test cases

 tools/include/nolibc/arch-mips.h             |  26 ++
 tools/include/nolibc/nolibc.h                |   9 +-
 tools/include/nolibc/sys.h                   | 391 +++----------------
 tools/include/nolibc/types.h                 |  11 +
 tools/include/nolibc/unistd.h                |  13 +-
 tools/testing/selftests/nolibc/nolibc-test.c |  90 +++++
 6 files changed, 191 insertions(+), 349 deletions(-)

-- 
2.25.1