4 files changed, 480 insertions, 67 deletions

diff --git a/sys/alpha/linux/linux.h b/sys/alpha/linux/linux.h
index c0fbc0a20fe2..f6bab97e92bb 100644
--- a/sys/alpha/linux/linux.h
+++ b/sys/alpha/linux/linux.h
@@ -25,7 +25,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- *	$Id: linux.h,v 1.3 1995/12/29 22:12:10 sos Exp $
+ *	$Id: linux.h,v 1.4 1996/01/30 22:56:29 mpp Exp $
  */
 
 #ifndef _I386_LINUX_LINUX_H_
@@ -55,9 +55,56 @@ typedef struct {
 } linux_sigaction_t;
 typedef int linux_key_t;
 
+/*
+ * The Linux sigcontext, pretty much a standard 386 trapframe.
+ */
+
+struct linux_sigcontext {
+	int	sc_gs;
+	int	sc_fs;
+	int     sc_es;
+	int     sc_ds;
+	int     sc_edi;
+	int     sc_esi;
+	int     sc_ebp;
+	int	sc_esp;
+	int     sc_ebx;
+	int     sc_edx;
+	int     sc_ecx;
+	int     sc_eax;
+	int     sc_trapno;
+	int     sc_err;
+	int     sc_eip;
+	int     sc_cs;
+	int     sc_eflags;
+	int     sc_esp_at_signal;
+	int     sc_ss;
+	int	sc_387;
+	int	sc_mask;
+	int	sc_cr2;
+};
+
+/*
+ * We make the stack look like Linux expects it when calling a signal
+ * handler, but use the BSD way of calling the handler and sigreturn().
+ * This means that we need to pass the pointer to the handler too.
+ * It is appended to the frame to not interfere with the rest of it.
+ */
+
+struct linux_sigframe {
+	int	sf_sig;
+	struct	linux_sigcontext sf_sc;
+	sig_t	sf_handler;
+};
+
 extern int bsd_to_linux_signal[];
 extern int linux_to_bsd_signal[];
 
+extern struct sysentvec linux_sysvec;
+
+struct image_params;
+int	linux_fixup __P((int **stack_base, struct image_params *iparams));
+
 /* misc defines */
 #define LINUX_NAME_MAX		255
 
@@ -421,9 +468,14 @@ extern int linux_to_bsd_signal[];
 #define LINUX_SNDCTL_DSP_GETISPACE	0x500D
 #define LINUX_SNDCTL_DSP_NONBLOCK	0x500E
 
-#ifdef KERNEL
-caddr_t	ua_alloc_init __P((int len));
-caddr_t	ua_alloc __P((int len));
-#endif
+/* Socket system defines */
+#define LINUX_SIOCGIFCONF		0x8912
+#define LINUX_SIOCGIFFLAGS		0x8913
+#define LINUX_SIOCGIFADDR		0x8915
+#define LINUX_SIOCGIFDSTADDR		0x8917
+#define LINUX_SIOCGIFBRDADDR		0x8919
+#define LINUX_SIOCGIFNETMASK		0x891b
+#define LINUX_SIOCADDMULTI		0x8931
+#define LINUX_SIOCDELMULTI		0x8932
 
 #endif /* !_I386_LINUX_LINUX_H_ */
diff --git a/sys/alpha/linux/linux_dummy.c b/sys/alpha/linux/linux_dummy.c
index 6c55613e6abc..2fcab4616a39 100644
--- a/sys/alpha/linux/linux_dummy.c
+++ b/sys/alpha/linux/linux_dummy.c
@@ -25,7 +25,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- *  $Id: linux_dummy.c,v 1.1 1995/06/25 17:32:33 sos Exp $
+ *  $Id: linux_dummy.c,v 1.2 1995/11/22 07:43:44 bde Exp $
  */
 
 #include <sys/param.h>
@@ -34,283 +34,264 @@
 #include <sys/proc.h>
 #include <sys/resourcevar.h>
 
-#include <i386/linux/sysproto.h>
+#include <i386/linux/linux.h>
+#include <i386/linux/linux_proto.h>
 
 int
-linux_setup(struct proc *p, void *args, int *retval)
+linux_setup(struct proc *p, struct linux_setup_args *args, int *retval)
 {
     printf("Linux-emul(%d): setup() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_break(struct proc *p, void *args, int *retval)
+linux_break(struct proc *p, struct linux_break_args *args, int *retval)
 {
     printf("Linux-emul(%d): break() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_stat(struct proc *p, void *args, int *retval)
+linux_stat(struct proc *p, struct linux_stat_args *args, int *retval)
 {
     printf("Linux-emul(%d): stat() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_fstat(struct proc *p, void *args, int *retval)
+linux_fstat(struct proc *p, struct linux_fstat_args *args, int *retval)
 {
     printf("Linux-emul(%d): fstat() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_mount(struct proc *p, void *args, int *retval)
+linux_mount(struct proc *p, struct linux_mount_args *args, int *retval)
 {
     printf("Linux-emul(%d): mount() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_umount(struct proc *p, void *args, int *retval)
+linux_umount(struct proc *p, struct linux_umount_args *args, int *retval)
 {
     printf("Linux-emul(%d): umount() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_stime(struct proc *p, void *args, int *retval)
+linux_stime(struct proc *p, struct linux_stime_args *args, int *retval)
 {
     printf("Linux-emul(%d): stime() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_ptrace(struct proc *p, void *args, int *retval)
+linux_ptrace(struct proc *p, struct linux_ptrace_args *args, int *retval)
 {
     printf("Linux-emul(%d): ptrace() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_pause(struct proc *p, void *args, int *retval)
-{
-    printf("Linux-emul(%d): pause() not supported\n", p->p_pid);
-    return ENOSYS;
-}
-
-int
-linux_stty(struct proc *p, void *args, int *retval)
+linux_stty(struct proc *p, struct linux_stty_args *args, int *retval)
 {
     printf("Linux-emul(%d): stty() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_gtty(struct proc *p, void *args, int *retval)
+linux_gtty(struct proc *p, struct linux_gtty_args *args, int *retval)
 {
     printf("Linux-emul(%d): gtty() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_nice(struct proc *p, void *args, int *retval)
+linux_nice(struct proc *p, struct linux_nice_args *args, int *retval)
 {
     printf("Linux-emul(%d): nice() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_ftime(struct proc *p, void *args, int *retval)
+linux_ftime(struct proc *p, struct linux_ftime_args *args, int *retval)
 {
     printf("Linux-emul(%d): ftime() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_prof(struct proc *p, void *args, int *retval)
+linux_prof(struct proc *p, struct linux_prof_args *args, int *retval)
 {
     printf("Linux-emul(%d): prof() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_signal(struct proc *p, void *args, int *retval)
-{
-    printf("Linux-emul(%d): signal() not supported\n", p->p_pid);
-    return ENOSYS;
-}
-
-int
-linux_phys(struct proc *p, void *args, int *retval)
+linux_phys(struct proc *p, struct linux_phys_args *args, int *retval)
 {
     printf("Linux-emul(%d): phys() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_lock(struct proc *p, void *args, int *retval)
+linux_lock(struct proc *p, struct linux_lock_args *args, int *retval)
 {
     printf("Linux-emul(%d): lock() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_mpx(struct proc *p, void *args, int *retval)
+linux_mpx(struct proc *p, struct linux_mpx_args *args, int *retval)
 {
     printf("Linux-emul(%d): mpx() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_ulimit(struct proc *p, void *args, int *retval)
+linux_ulimit(struct proc *p, struct linux_ulimit_args *args, int *retval)
 {
     printf("Linux-emul(%d): ulimit() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_olduname(struct proc *p, void *args, int *retval)
+linux_olduname(struct proc *p, struct linux_olduname_args *args, int *retval)
 {
     printf("Linux-emul(%d): olduname() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_ustat(struct proc *p, void *args, int *retval)
+linux_ustat(struct proc *p, struct linux_ustat_args *args, int *retval)
 {
     printf("Linux-emul(%d): ustat() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_ioperm(struct proc *p, void *args, int *retval)
+linux_ioperm(struct proc *p, struct linux_ioperm_args *args, int *retval)
 {
     printf("Linux-emul(%d): ioperm() not supported\n", p->p_pid);
     return 0; /* EINVAL SOS XXX */
 }
 
 int
-linux_syslog(struct proc *p, void *args, int *retval)
+linux_ksyslog(struct proc *p, struct linux_ksyslog_args *args, int *retval)
 {
-    printf("Linux-emul(%d): syslog() not supported (BSD sigreturn)\n",p->p_pid);
-    return sigreturn(p, args, retval);
+    printf("Linux-emul(%d): ksyslog(%x) not supported\n",
+	p->p_pid, args->what);
+    return ENOSYS;	/* EPERM - Peter - it's a root-only thing */
 }
 
 int
-linux_iopl(struct proc *p, void *args, int *retval)
+linux_iopl(struct proc *p, struct linux_iopl_args *args, int *retval)
 {
     printf("Linux-emul(%d): iopl() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_vhangup(struct proc *p, void *args, int *retval)
+linux_vhangup(struct proc *p, struct linux_vhangup_args *args, int *retval)
 {
     printf("Linux-emul(%d): vhangup() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_idle(struct proc *p, void *args, int *retval)
+linux_idle(struct proc *p, struct linux_idle_args *args, int *retval)
 {
     printf("Linux-emul(%d): idle() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_vm86(struct proc *p, void *args, int *retval)
+linux_vm86(struct proc *p, struct linux_vm86_args *args, int *retval)
 {
     printf("Linux-emul(%d): vm86() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_swapoff(struct proc *p, void *args, int *retval)
+linux_swapoff(struct proc *p, struct linux_swapoff_args *args, int *retval)
 {
     printf("Linux-emul(%d): swapoff() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_sysinfo(struct proc *p, void *args, int *retval)
+linux_sysinfo(struct proc *p, struct linux_sysinfo_args *args, int *retval)
 {
     printf("Linux-emul(%d): sysinfo() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_sigreturn(struct proc *p, void *args, int *retval)
-{
-    printf("Linux-emul(%d): sigreturn() not supported\n", p->p_pid);
-    return ENOSYS;
-}
-
-int
-linux_clone(struct proc *p, void *args, int *retval)
+linux_clone(struct proc *p, struct linux_clone_args *args, int *retval)
 {
     printf("Linux-emul(%d): clone() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_uname(struct proc *p, void *args, int *retval)
+linux_uname(struct proc *p, struct linux_uname_args *args, int *retval)
 {
     printf("Linux-emul(%d): uname() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_modify_ldt(struct proc *p, void *args, int *retval)
+linux_modify_ldt(struct proc *p, struct linux_modify_ldt_args *args, int *retval)
 {
     printf("Linux-emul(%d): modify_ldt() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_adjtimex(struct proc *p, void *args, int *retval)
+linux_adjtimex(struct proc *p, struct linux_adjtimex_args *args, int *retval)
 {
     printf("Linux-emul(%d): adjtimex() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_create_module(struct proc *p, void *args, int *retval)
+linux_create_module(struct proc *p, struct linux_create_module_args *args, int *retval)
 {
     printf("Linux-emul(%d): create_module() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_init_module(struct proc *p, void *args, int *retval)
+linux_init_module(struct proc *p, struct linux_init_module_args *args, int *retval)
 {
     printf("Linux-emul(%d): init_module() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_delete_module(struct proc *p, void *args, int *retval)
+linux_delete_module(struct proc *p, struct linux_delete_module_args *args, int *retval)
 {
     printf("Linux-emul(%d): delete_module() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_get_kernel_syms(struct proc *p, void *args, int *retval)
+linux_get_kernel_syms(struct proc *p, struct linux_get_kernel_syms_args *args, int *retval)
 {
     printf("Linux-emul(%d): get_kernel_syms() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_quotactl(struct proc *p, void *args, int *retval)
+linux_quotactl(struct proc *p, struct linux_quotactl_args *args, int *retval)
 {
     printf("Linux-emul(%d): quotactl() not supported\n", p->p_pid);
     return ENOSYS;
 }
 
 int
-linux_bdflush(struct proc *p, void *args, int *retval)
+linux_bdflush(struct proc *p, struct linux_bdflush_args *args, int *retval)
 {
     printf("Linux-emul(%d): bdflush() not supported\n", p->p_pid);
     return ENOSYS;
diff --git a/sys/alpha/linux/linux_genassym.c b/sys/alpha/linux/linux_genassym.c
new file mode 100644
index 000000000000..c52294880775
--- /dev/null
+++ b/sys/alpha/linux/linux_genassym.c
@@ -0,0 +1,22 @@
+#include <stdio.h>
+#include <sys/param.h>
+#include <sys/buf.h>
+#include <sys/proc.h>
+#include <i386/linux/linux.h>
+
+extern int	main __P((void));
+
+int
+main()
+{
+	struct linux_sigframe *linux_sigf = (struct linux_sigframe *)0;
+	struct linux_sigcontext *linux_sc = (struct linux_sigcontext *)0;
+
+	printf("#define\tLINUX_SIGF_HANDLER %d\n", &linux_sigf->sf_handler);
+	printf("#define\tLINUX_SIGF_SC %d\n", &linux_sigf->sf_sc);
+	printf("#define\tLINUX_SC_FS %d\n", &linux_sc->sc_fs);
+	printf("#define\tLINUX_SC_GS %d\n", &linux_sc->sc_gs);
+	printf("#define\tLINUX_SC_EFLAGS %d\n", &linux_sc->sc_eflags);
+
+	return (0);
+}
diff --git a/sys/alpha/linux/linux_sysvec.c b/sys/alpha/linux/linux_sysvec.c
new file mode 100644
index 000000000000..92781027d986
--- /dev/null
+++ b/sys/alpha/linux/linux_sysvec.c
@@ -0,0 +1,358 @@
+/*-
+ * Copyright (c) 1994-1995 Søren Schmidt
+ * All rights reserved.
+ *
+ * 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 
+ *    in this position and unchanged.
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software withough specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ *
+ *  $Id: linux_sysent.c,v 1.4 1996/01/14 10:59:57 sos Exp $
+ */
+
+/* XXX we use functions that might not exist. */
+#define	COMPAT_43	1
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/sysproto.h>
+#include <sys/sysent.h>
+#include <sys/imgact.h>
+#include <sys/signalvar.h>
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+#include <vm/vm_prot.h>
+#include <vm/lock.h>
+#include <vm/vm_kern.h>
+#include <vm/vm_object.h>
+#include <vm/vm_page.h>
+#include <vm/vm_map.h>
+#include <vm/vm_pager.h>
+#include <vm/vm_extern.h>
+#include <sys/user.h>
+#include <sys/exec.h>
+#include <machine/cpu.h>
+#include <machine/frame.h>
+#include <machine/reg.h>
+#include <machine/specialreg.h>
+#include <machine/psl.h>
+#include <machine/sysarch.h>
+#include <machine/md_var.h>
+
+#include <i386/linux/linux.h>
+#include <i386/linux/linux_proto.h>
+#include <i386/linux/linux_syscall.h>
+
+/*
+ * Linux syscalls return negative errno's, we do positive and map them
+ */
+int bsd_to_linux_errno[ELAST] = {
+      -0,  -1,  -2,  -3,  -4,  -5,  -6,  -7,  -8,  -9,
+     -10, -35, -12, -13, -14, -15, -16, -17, -18, -19,
+     -20, -21, -22, -23, -24, -25, -26, -27, -28, -29,
+     -30, -31, -32, -33, -34, -11,-115,-114, -88, -89,
+     -90, -91, -92, -93, -94, -95, -96, -97, -98, -99,
+    -100,-101,-102,-103,-104,-105,-106,-107,-108,-109,
+    -110,-111, -40, -36,-112,-113, -39, -11, -87,-122,
+    -116, -66,  -6,  -6,  -6,  -6,  -6, -37, -38,  -9,
+      -6, 
+};
+
+int bsd_to_linux_signal[NSIG] = {
+    0, LINUX_SIGHUP, LINUX_SIGINT, LINUX_SIGQUIT,
+    LINUX_SIGILL, LINUX_SIGTRAP, LINUX_SIGABRT, 0,
+    LINUX_SIGFPE, LINUX_SIGKILL, LINUX_SIGBUS, LINUX_SIGSEGV, 
+    0, LINUX_SIGPIPE, LINUX_SIGALRM, LINUX_SIGTERM,
+    LINUX_SIGURG, LINUX_SIGSTOP, LINUX_SIGTSTP, LINUX_SIGCONT,	
+    LINUX_SIGCHLD, LINUX_SIGTTIN, LINUX_SIGTTOU, LINUX_SIGIO, 
+    LINUX_SIGXCPU, LINUX_SIGXFSZ, LINUX_SIGVTALRM, LINUX_SIGPROF, 
+    LINUX_SIGWINCH, 0, LINUX_SIGUSR1, LINUX_SIGUSR2
+};
+
+int linux_to_bsd_signal[LINUX_NSIG] = {
+    0, SIGHUP, SIGINT, SIGQUIT, SIGILL, SIGTRAP, SIGABRT, SIGEMT,
+    SIGFPE, SIGKILL, SIGUSR1, SIGSEGV, SIGUSR2, SIGPIPE, SIGALRM, SIGTERM, 
+    SIGBUS, SIGCHLD, SIGCONT, SIGSTOP, SIGTSTP, SIGTTIN, SIGTTOU, SIGIO,
+    SIGXCPU, SIGXFSZ, SIGVTALRM, SIGPROF, SIGWINCH, SIGURG, SIGURG, 0
+};
+
+int linux_fixup(int **stack_base, struct image_params *imgp)
+{
+    int *argv, *envp;
+
+    argv = *stack_base;
+    envp = *stack_base + (imgp->argc + 1);
+    (*stack_base)--;
+    **stack_base = (int)envp;
+    (*stack_base)--;
+    **stack_base = (int)argv;
+    (*stack_base)--;
+    **stack_base = (int)imgp->argc;
+    return 0;			/* XXX */
+}
+
+extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL];
+
+static void linux_sendsig(sig_t action,
+			  int sig,
+			  int returnmask,
+			  unsigned code);
+
+extern int _ucodesel, _udatasel;
+
+/*
+ * Send an interrupt to process.
+ *
+ * Stack is set up to allow sigcode stored
+ * in u. to call routine, followed by kcall
+ * to sigreturn routine below.  After sigreturn
+ * resets the signal mask, the stack, and the
+ * frame pointer, it returns to the user
+ * specified pc, psl.
+ */
+
+static void
+linux_sendsig(catcher, sig, mask, code)
+	sig_t catcher;
+	int sig;
+	int mask;
+	unsigned code;
+{
+	register struct proc *p = curproc;
+	register int *regs;
+	struct linux_sigframe *fp, frame;
+	struct sigacts *psp = p->p_sigacts;
+	int oonstack;
+
+	regs = p->p_md.md_regs;
+	oonstack = psp->ps_sigstk.ss_flags & SS_ONSTACK;
+
+#ifdef DEBUG
+	printf("Linux-emul(%d): linux_sendsig(%8x, %d, %d, %d)\n",
+		p->p_pid, catcher, sig, mask, code);
+#endif
+	/*
+	 * Allocate space for the signal handler context.
+	 */
+	if ((psp->ps_flags & SAS_ALTSTACK) && !oonstack &&
+	    (psp->ps_sigonstack & sigmask(sig))) {
+		fp = (struct linux_sigframe *)(psp->ps_sigstk.ss_sp +
+		    psp->ps_sigstk.ss_size - sizeof(struct linux_sigframe));
+		psp->ps_sigstk.ss_flags |= SS_ONSTACK;
+	} else {
+		fp = (struct linux_sigframe *)regs[tESP] - 1;
+	}
+
+	/*
+	 * grow() will return FALSE if the fp will not fit inside the stack
+	 *	and the stack can not be grown. useracc will return FALSE
+	 *	if access is denied.
+	 */
+	if ((grow(p, (int)fp) == FALSE) ||
+	    (useracc((caddr_t)fp, sizeof (struct linux_sigframe), B_WRITE) == FALSE)) {
+		/*
+		 * Process has trashed its stack; give it an illegal
+		 * instruction to halt it in its tracks.
+		 */
+		SIGACTION(p, SIGILL) = SIG_DFL;
+		sig = sigmask(SIGILL);
+		p->p_sigignore &= ~sig;
+		p->p_sigcatch &= ~sig;
+		p->p_sigmask &= ~sig;
+		psignal(p, SIGILL);
+		return;
+	}
+
+	/*
+	 * Build the argument list for the signal handler.
+	 */
+	if (p->p_sysent->sv_sigtbl) {
+		if (sig < p->p_sysent->sv_sigsize)
+			sig = p->p_sysent->sv_sigtbl[sig];
+		else
+			sig = p->p_sysent->sv_sigsize + 1;
+	}
+
+	frame.sf_handler = catcher;
+	frame.sf_sig = sig;
+
+	/*
+	 * Build the signal context to be used by sigreturn.
+	 */
+	frame.sf_sc.sc_mask   = mask;
+	__asm("movl %%gs,%w0" : "=r" (frame.sf_sc.sc_gs));
+	__asm("movl %%fs,%w0" : "=r" (frame.sf_sc.sc_fs));
+	frame.sf_sc.sc_es     = regs[tES];
+	frame.sf_sc.sc_ds     = regs[tDS];
+	frame.sf_sc.sc_edi    = regs[tEDI];
+	frame.sf_sc.sc_esi    = regs[tESI];
+	frame.sf_sc.sc_ebp    = regs[tEBP];
+	frame.sf_sc.sc_ebx    = regs[tEBX];
+	frame.sf_sc.sc_edx    = regs[tEDX];
+	frame.sf_sc.sc_ecx    = regs[tECX];
+	frame.sf_sc.sc_eax    = regs[tEAX];
+	frame.sf_sc.sc_eip    = regs[tEIP];
+	frame.sf_sc.sc_cs     = regs[tCS];
+	frame.sf_sc.sc_eflags = regs[tEFLAGS];
+	frame.sf_sc.sc_esp_at_signal = regs[tESP];
+	frame.sf_sc.sc_ss     = regs[tSS];
+	frame.sf_sc.sc_err    = regs[tERR];
+	frame.sf_sc.sc_trapno = code;	/* XXX ???? */
+
+	if (copyout(&frame, fp, sizeof(frame)) != 0) {
+		/*
+		 * Process has trashed its stack; give it an illegal
+		 * instruction to halt it in its tracks.
+		 */
+		sigexit(p, SIGILL);
+		/* NOTREACHED */
+	}
+
+	/*
+	 * Build context to run handler in.
+	 */
+	regs[tESP] = (int)fp;
+	regs[tEIP] = (int)(((char *)PS_STRINGS) - *(p->p_sysent->sv_szsigcode));
+	regs[tEFLAGS] &= ~PSL_VM;
+	regs[tCS] = _ucodesel;
+	regs[tDS] = _udatasel;
+	regs[tES] = _udatasel;
+	regs[tSS] = _udatasel;
+}
+
+/*
+ * System call to cleanup state after a signal
+ * has been taken.  Reset signal mask and
+ * stack state from context left by sendsig (above).
+ * Return to previous pc and psl as specified by
+ * context left by sendsig. Check carefully to
+ * make sure that the user has not modified the
+ * psl to gain improper privileges or to cause
+ * a machine fault.
+ */
+int
+linux_sigreturn(p, args, retval)
+	struct proc *p;
+	struct linux_sigreturn_args *args;
+	int *retval;
+{
+	struct linux_sigcontext *scp, context;
+	register int *regs;
+	int eflags;
+
+	regs = p->p_md.md_regs;
+
+#ifdef DEBUG
+	printf("Linux-emul(%d): linux_sigreturn(%8x)\n", p->p_pid, args->scp);
+#endif
+	/*
+	 * The trampoline code hands us the context.
+	 * It is unsafe to keep track of it ourselves, in the event that a
+	 * program jumps out of a signal handler.
+	 */
+	scp = args->scp;
+	if (copyin((caddr_t)scp, &context, sizeof(*scp)) != 0)
+		return (EFAULT);
+
+	/*
+	 * Check for security violations.
+	 */
+#define	EFLAGS_SECURE(ef, oef)	((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0)
+	eflags = context.sc_eflags;
+	/*
+	 * XXX do allow users to change the privileged flag PSL_RF.  The
+	 * cpu sets PSL_RF in tf_eflags for faults.  Debuggers should
+	 * sometimes set it there too.  tf_eflags is kept in the signal
+	 * context during signal handling and there is no other place
+	 * to remember it, so the PSL_RF bit may be corrupted by the
+	 * signal handler without us knowing.  Corruption of the PSL_RF
+	 * bit at worst causes one more or one less debugger trap, so
+	 * allowing it is fairly harmless.
+	 */
+	if (!EFLAGS_SECURE(eflags & ~PSL_RF, regs[tEFLAGS] & ~PSL_RF)) {
+    		return(EINVAL);
+	}
+
+	/*
+	 * Don't allow users to load a valid privileged %cs.  Let the
+	 * hardware check for invalid selectors, excess privilege in
+	 * other selectors, invalid %eip's and invalid %esp's.
+	 */
+#define	CS_SECURE(cs)	(ISPL(cs) == SEL_UPL)
+	if (!CS_SECURE(context.sc_cs)) {
+		trapsignal(p, SIGBUS, T_PROTFLT);
+		return(EINVAL);
+	}
+
+	p->p_sigacts->ps_sigstk.ss_flags &= ~SS_ONSTACK;
+	p->p_sigmask = context.sc_mask &~
+		(sigmask(SIGKILL)|sigmask(SIGCONT)|sigmask(SIGSTOP));
+	/*
+	 * Restore signal context.
+	 */
+	/* %fs and %gs were restored by the trampoline. */
+	regs[tES]     = context.sc_es;
+	regs[tDS]     = context.sc_ds;
+	regs[tEDI]    = context.sc_edi;
+	regs[tESI]    = context.sc_esi;
+	regs[tEBP]    = context.sc_ebp;
+	regs[tEBX]    = context.sc_ebx;
+	regs[tEDX]    = context.sc_edx;
+	regs[tECX]    = context.sc_ecx;
+	regs[tEAX]    = context.sc_eax;
+	regs[tEIP]    = context.sc_eip;
+	regs[tCS]     = context.sc_cs;
+	regs[tEFLAGS] = eflags;
+	regs[tESP]    = context.sc_esp_at_signal;
+	regs[tSS]     = context.sc_ss;
+
+	return (EJUSTRETURN);
+}
+
+static void
+linux_prepsyscall(struct trapframe *tf, int *args, u_int *code, caddr_t *params)
+{
+	int i;
+	args[0] = tf->tf_ebx;
+	args[1] = tf->tf_ecx;
+	args[2] = tf->tf_edx;
+	args[3] = tf->tf_esi;
+	args[4] = tf->tf_edi;
+	*params = NULL;		/* no copyin */
+}
+
+extern char linux_sigcode[];
+extern int linux_szsigcode;
+
+struct sysentvec linux_sysvec = {
+    sizeof (linux_sysent) / sizeof(linux_sysent[0]),
+    linux_sysent,
+    0xff,
+    NSIG,
+    bsd_to_linux_signal,
+    ELAST, 
+    bsd_to_linux_errno,
+    linux_fixup,
+    linux_sendsig,
+    linux_sigcode,	
+    &linux_szsigcode,
+    linux_prepsyscall,
+};