Add an initial console device and open fd's 0/1/2 for initproc. This is

again useful in standalone-type environments such as Xen, where all
printf/etc calls go through the rump kernel.

sys/rump/librump/rumpkern/Makefile.rumpkern

@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile.rumpkern,v 1.131 2013/09/03 21:32:21 pooka Exp $
+#	$NetBSD: Makefile.rumpkern,v 1.132 2013/09/07 17:58:00 pooka Exp $
 #
 
 .include "${RUMPTOP}/Makefile.rump"
@@ -19,7 +19,7 @@ LIB=		rump
 #
 # Source modules, first the ones specifically implemented for librump.
 # 
-SRCS+=	rump.c rumpcopy.c emul.c intr.c lwproc.c klock.c	\
+SRCS+=	rump.c rumpcopy.c cons.c emul.c intr.c lwproc.c klock.c	\
 	kobj_rename.c ltsleep.c scheduler.c			\
 	signals.c sleepq.c threads.c vm.c cprng_stub.c
 

sys/rump/librump/rumpkern/cons.c

@@ -0,0 +1,133 @@
+/*	$NetBSD: cons.c,v 1.1 2013/09/07 17:58:00 pooka Exp $	*/
+
+/*
+ * Copyright (c) 2013 Antti Kantee.  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.
+ * 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 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 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.
+ */
+
+/*
+ * rumpcons, a (very) simple console-type device which relays output
+ * to the rumpuser_putchar() hypercall.  This is most useful in
+ * environments where there is no Unix-like host (e.g. Xen DomU).
+ * It's currently a truly half duplex console since there is support
+ * only for writing to the console (there is no hypercall for reading
+ * the host console).
+ */
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: cons.c,v 1.1 2013/09/07 17:58:00 pooka Exp $");
+
+#include <sys/param.h>
+#include <sys/file.h>
+#include <sys/filedesc.h>
+#include <sys/kernel.h>
+#include <sys/kmem.h>
+#include <sys/proc.h>
+#include <sys/stat.h>
+
+#include <rump/rumpuser.h>
+
+#include "rump_private.h"
+
+static int rumpcons_write(struct file *, off_t *, struct uio *,
+			  kauth_cred_t, int);
+static int rumpcons_stat(struct file *, struct stat *);
+
+static const struct fileops rumpcons_fileops = {
+	.fo_read = (void *)nullop,
+	.fo_write = rumpcons_write,
+	.fo_ioctl = fbadop_ioctl,
+	.fo_fcntl = fnullop_fcntl,
+	.fo_poll = fnullop_poll,
+	.fo_stat = rumpcons_stat,
+	.fo_close = (void *)nullop,
+	.fo_kqfilter = fnullop_kqfilter,
+	.fo_restart = fnullop_restart,
+};
+
+void
+rump_consdev_init(void)
+{
+	struct file *fp;
+	int fd, error;
+
+	/*
+	 * We want to open the descriptors for the implicit proc
+	 * so that they get inherited by default to all processes.
+	 */
+	KASSERT(curproc->p_pid == 1);
+	KASSERT(fd_getfile(0) == NULL);
+
+	/* then, map a file descriptor to the device */
+	if ((error = fd_allocfile(&fp, &fd)) != 0)
+		panic("cons fd_allocfile failed: %d", error);
+
+	fp->f_flag = FWRITE;
+	fp->f_type = DTYPE_MISC;
+	fp->f_ops = &rumpcons_fileops;
+	fp->f_data = NULL;
+	fd_affix(curproc, fp, fd);
+
+	KASSERT(fd == 0);
+	error += fd_dup2(fp, 1, 0);
+	error += fd_dup2(fp, 2, 0);
+
+	if (error)
+		panic("failed to dup fd 0/1/2");
+}
+
+static int
+rumpcons_write(struct file *fp, off_t *off, struct uio *uio,
+	kauth_cred_t cred, int flags)
+{
+	char *buf;
+	size_t len, n;
+	int error;
+
+	buf = kmem_alloc(PAGE_SIZE, KM_SLEEP);
+	while (uio->uio_resid > 0) {
+		len = min(PAGE_SIZE, uio->uio_resid);
+		error = uiomove(buf, len, uio);
+		if (error)
+			break;
+
+		for (n = 0; n < len; n++) {
+			rumpuser_putchar(*(buf+n));
+		}
+	}
+	kmem_free(buf, PAGE_SIZE);
+
+	return error;
+}
+
+static int
+rumpcons_stat(struct file *fp, struct stat *sb)
+{
+
+	memset(sb, 0, sizeof(*sb));
+	sb->st_mode = 0600;
+	sb->st_atimespec = sb->st_mtimespec = sb->st_ctimespec = boottime;
+	sb->st_birthtimespec = boottime;
+
+	return 0;
+}

sys/rump/librump/rumpkern/rump.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: rump.c,v 1.273 2013/09/04 17:56:08 pooka Exp $	*/
+/*	$NetBSD: rump.c,v 1.274 2013/09/07 17:58:00 pooka Exp $	*/
 
 /*
  * Copyright (c) 2007-2011 Antti Kantee.  All Rights Reserved.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rump.c,v 1.273 2013/09/04 17:56:08 pooka Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rump.c,v 1.274 2013/09/07 17:58:00 pooka Exp $");
 
 #include <sys/systm.h>
 #define ELFSIZE ARCH_ELFSIZE
@@ -251,7 +251,7 @@ rump_init(void)
 	struct timespec ts;
 	int64_t sec;
 	long nsec;
-	struct lwp *l;
+	struct lwp *l, *initlwp;
 	int i, numcpu;
 
 	/* not reentrant */
@@ -471,10 +471,10 @@ rump_init(void)
 		vmem_rehash_start();
 
 	/*
-	 * Create init, used to attach implicit threads in rump.
+	 * Create init (proc 1), used to attach implicit threads in rump.
 	 * (note: must be done after vfsinit to get cwdi)
 	 */
-	(void)rump__lwproc_alloclwp(NULL); /* dummy thread for initproc */
+	initlwp = rump__lwproc_alloclwp(NULL);
 	mutex_enter(proc_lock);
 	initproc = proc_find_raw(1);
 	mutex_exit(proc_lock);
@@ -542,8 +542,14 @@ rump_init(void)
 
 	rump_component_init(RUMP_COMPONENT_POSTINIT);
 
-	/* release cpu */
+	/* component inits done */
 	bootlwp = NULL;
+
+	/* open 0/1/2 for init */
+	rump_lwproc_switch(initlwp);
+	rump_consdev_init();
+
+	/* release cpu */
 	rump_unschedule();
 
 	return 0;

sys/rump/librump/rumpkern/rump_private.h

@@ -1,4 +1,4 @@
-/*	$NetBSD: rump_private.h,v 1.75 2013/09/03 19:55:13 pooka Exp $	*/
+/*	$NetBSD: rump_private.h,v 1.76 2013/09/07 17:58:00 pooka Exp $	*/
 
 /*
  * Copyright (c) 2007-2011 Antti Kantee.  All Rights Reserved.
@@ -145,4 +145,6 @@ void	rump_xc_highpri(struct cpu_info *);
 void	rump_thread_init(void);
 void	rump_thread_allow(void);
 
+void	rump_consdev_init(void);
+
 #endif /* _SYS_RUMP_PRIVATE_H_ */