It is able to pass the 6th argument like the 5th argument via the stack for mips, let's add a new my_syscall6() now, see [1] for details:
The mips/o32 system call convention passes arguments 5 through 8 on the user stack.
Both mmap() and pselect6() require my_syscall6().
[1]: https://man7.org/linux/man-pages/man2/syscall.2.html
Signed-off-by: Zhangjin Wu falcon@tinylab.org --- tools/include/nolibc/arch-mips.h | 27 ++++++++++++++++++++++++++- tools/include/nolibc/nolibc.h | 9 ++++----- 2 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h index 1848f57777c4..a2bfdf57b957 100644 --- a/tools/include/nolibc/arch-mips.h +++ b/tools/include/nolibc/arch-mips.h @@ -166,7 +166,7 @@ struct sys_stat_struct { __asm__ volatile ( \ "addiu $sp, $sp, -32\n" \ "sw %7, 16($sp)\n" \ - "syscall\n " \ + "syscall\n" \ "addiu $sp, $sp, 32\n" \ : "=r" (_num), "=r"(_arg4) \ : "0"(_num), \ @@ -176,6 +176,31 @@ struct sys_stat_struct { _arg4 ? -_num : _num; \ })
+#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \ +({ \ + register long _num __asm__ ("v0") = (num); \ + register long _arg1 __asm__ ("a0") = (long)(arg1); \ + register long _arg2 __asm__ ("a1") = (long)(arg2); \ + register long _arg3 __asm__ ("a2") = (long)(arg3); \ + register long _arg4 __asm__ ("a3") = (long)(arg4); \ + register long _arg5 = (long)(arg5); \ + register long _arg6 = (long)(arg6); \ + \ + __asm__ volatile ( \ + "addiu $sp, $sp, -32\n" \ + "sw %7, 16($sp)\n" \ + "sw %8, 20($sp)\n" \ + "syscall\n" \ + "addiu $sp, $sp, 32\n" \ + : "=r" (_num), "=r"(_arg4) \ + : "0"(_num), \ + "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \ + "r"(_arg6) \ + : _NOLIBC_SYSCALL_CLOBBERLIST \ + ); \ + _arg4 ? -_num : _num; \ +}) + char **environ __attribute__((weak)); const unsigned long *_auxv __attribute__((weak));
diff --git a/tools/include/nolibc/nolibc.h b/tools/include/nolibc/nolibc.h index 05a228a6ee78..1f8d821000ac 100644 --- a/tools/include/nolibc/nolibc.h +++ b/tools/include/nolibc/nolibc.h @@ -13,11 +13,10 @@ * Syscalls are split into 3 levels: * - The lower level is the arch-specific syscall() definition, consisting in * assembly code in compound expressions. These are called my_syscall0() to - * my_syscall6() depending on the number of arguments. The MIPS - * implementation is limited to 5 arguments. All input arguments are cast - * to a long stored in a register. These expressions always return the - * syscall's return value as a signed long value which is often either a - * pointer or the negated errno value. + * my_syscall6() depending on the number of arguments. All input arguments + * are castto a long stored in a register. These expressions always return + * the syscall's return value as a signed long value which is often either + * a pointer or the negated errno value. * * - The second level is mostly architecture-independent. It is made of * static functions called sys_<name>() which rely on my_syscallN()