/*      $NetBSD: sys_syscall.c,v 1.16 2025/06/01 23:30:36 bad Exp $     */

/*-
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by David Laight.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: sys_syscall.c,v 1.16 2025/06/01 23:30:36 bad Exp $");

#include <sys/syscall_stats.h>
#include <sys/syscallvar.h>

/*
* MI indirect system call support.
* Included from sys_scdebug.c and compat/netbsd32/netbsd32_indirect.c
*
* SYS_SYSCALL is set to the required function name.
*/

#define CONCAT(a,b) __CONCAT(a,b)

static void
CONCAT(SYS_SYSCALL, _biglockcheck)(struct proc *p, int code)
{

#ifdef DIAGNOSTIC
      kpreempt_disable();     /* make curcpu() stable */
      KASSERTMSG(curcpu()->ci_biglock_count == 0,
          "syscall %ld of emul %s leaked %d kernel locks",
          (long)code, p->p_emul->e_name, curcpu()->ci_biglock_count);
      kpreempt_enable();
#endif
}

int
SYS_SYSCALL(struct lwp *l, const struct CONCAT(SYS_SYSCALL, _args) *uap,
   register_t *rval)
{
       /* {
               syscallarg(int) code;
               syscallarg(register_t) args[SYS_MAXSYSARGS];
       } */
       const struct sysent *callp;
       struct proc *p = l->l_proc;
       int code;
       int error;
#ifdef NETBSD32_SYSCALL
       register_t args64[SYS_MAXSYSARGS];
       int i, narg;
       #define TRACE_ARGS args64
#else
       #define TRACE_ARGS &SCARG(uap, args[0])
#endif

       callp = p->p_emul->e_sysent;

       code = SCARG(uap, code) & (SYS_NSYSENT - 1);
       SYSCALL_COUNT(syscall_counts, code);
       callp += code;

       if (__predict_false(callp->sy_flags & SYCALL_INDIRECT))
               return ENOSYS;

       if (__predict_true(!p->p_trace_enabled)) {
               error = sy_call(callp, l, &uap->args, rval);
               CONCAT(SYS_SYSCALL, _biglockcheck)(p, code);
               return error;
       }

#ifdef NETBSD32_SYSCALL
       narg = callp->sy_narg;
       for (i = 0; i < narg; i++)
               args64[i] = SCARG(uap, args[i]);
#endif

       error = trace_enter(code, callp, TRACE_ARGS);
       if (__predict_true(error == 0))
               error = sy_call(callp, l, &uap->args, rval);
       trace_exit(code, callp, &uap->args, rval, error);
       CONCAT(SYS_SYSCALL, _biglockcheck)(p, code);
       return error;

       #undef TRACE_ARGS
}