Add the outline of the "/dev/geom.ctl" handling code.

Sponsored by:	DARPA & NAI Labs.

sys/geom/geom.h

@@ -302,7 +302,14 @@ extern struct sx topology_lock;
 
 #endif /* _KERNEL */
 
-#define GEOMGETCONF _IOWR('G',  0, struct sbuf)
+/*
+ * IOCTLS for talking to the geom.ctl device.
+ */
+struct geomgetconf {
+	char	*ptr;
+	u_int	len;
+};
+#define GEOMGETCONF _IOW('G',  0, struct geomgetconf)
 
 /* geom_enc.c */
 uint16_t g_dec_be2(u_char *p);

sys/geom/geom_ctl.c

@@ -0,0 +1,193 @@
+/*-
+ * Copyright (c) 2002 Poul-Henning Kamp
+ * Copyright (c) 2002 Networks Associates Technology, Inc.
+ * All rights reserved.
+ *
+ * This software was developed for the FreeBSD Project by Poul-Henning Kamp
+ * and NAI Labs, the Security Research Division of Network Associates, Inc.
+ * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
+ * DARPA CHATS research program.
+ *
+ * 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.
+ * 3. The names of the authors may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 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.
+ *
+ * $FreeBSD$
+ */
+
+#include "opt_geom.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/sysctl.h>
+#include <sys/bio.h>
+#include <sys/conf.h>
+#include <sys/disk.h>
+#include <sys/malloc.h>
+#include <sys/sysctl.h>
+#include <sys/stdint.h>
+
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <geom/geom.h>
+#include <geom/geom_int.h>
+
+static g_access_t g_ctl_access;
+static g_start_t g_ctl_start;
+static void g_ctl_init(void);
+static d_ioctl_t g_ctl_ioctl;
+
+struct g_class g_ctl_class = {
+	"GEOMCTL",
+	NULL,
+	NULL,
+	G_CLASS_INITIALIZER
+};
+
+DECLARE_GEOM_CLASS_INIT(g_ctl_class, g_ctl, g_ctl_init);
+
+/*
+ * We cannot do create our geom.ctl geom/provider in g_ctl_init() because
+ * the event thread has to finish adding our class first and that doesn't
+ * happen until later.  We know however, that the events are processed in
+ * FIFO order, so scheduling g_ctl_init2() with g_call_me() is safe.
+ */
+
+static void
+g_ctl_init2(void *p __unused)
+{
+	struct g_geom *gp;
+	struct g_provider *pp;
+
+	g_topology_assert();
+	gp = g_new_geomf(&g_ctl_class, "geom.ctl");
+	gp->start = g_ctl_start;
+	gp->access = g_ctl_access;
+	pp = g_new_providerf(gp, "%s", gp->name);
+	g_error_provider(pp, 0);
+}
+
+static void
+g_ctl_init(void)
+{
+	mtx_unlock(&Giant);
+	g_add_class(&g_ctl_class);
+	g_call_me(g_ctl_init2, NULL);
+	mtx_lock(&Giant);
+}
+
+/*
+ * We allow any kind of access.  Access control is handled at the devfs
+ * level.
+ */
+
+static int
+g_ctl_access(struct g_provider *pp, int r, int w, int e)
+{
+	int error;
+
+	g_trace(G_T_ACCESS, "g_ctl_access(%s, %d, %d, %d)",
+	    pp->name, r, w, e);
+
+	g_topology_assert();
+	error = 0;
+	return (error);
+}
+
+static void
+g_ctl_start(struct bio *bp)
+{
+	struct g_ioctl *gio;
+	int error;
+
+	switch(bp->bio_cmd) {
+	case BIO_DELETE:
+	case BIO_READ:
+	case BIO_WRITE:
+		error = EOPNOTSUPP;
+		break;
+	case BIO_GETATTR:
+	case BIO_SETATTR:
+		if (strcmp(bp->bio_attribute, "GEOM::ioctl") ||
+		    bp->bio_length != sizeof *gio) {
+			error = EOPNOTSUPP;
+			break;
+		}
+		gio = (struct g_ioctl *)bp->bio_data;
+		gio->func = g_ctl_ioctl;
+		error = EDIRIOCTL;
+		break;
+	default:
+		error = EOPNOTSUPP;
+		break;
+	}
+	g_io_deliver(bp, error);
+	return;
+}
+
+/*
+ * All the stuff above is really just needed to get to this one.
+ */
+
+static int
+g_ctl_ioctl_getconf(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
+{
+	struct geomgetconf *gcp;
+	struct sbuf *sb;
+	int error;
+	u_int l;
+
+	gcp = (struct geomgetconf *)data;
+	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
+	sbuf_clear(sb);
+	g_confxml(sb);
+	l = sbuf_len(sb) + 1;
+	if (l > gcp->len)
+		error = ENOMEM;
+	else
+		error = copyout(sbuf_data(sb), gcp->ptr, l);
+	sbuf_delete(sb);
+	return(error);
+}
+
+static int
+g_ctl_ioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
+{
+	int error;
+
+	DROP_GIANT();
+	g_topology_lock();
+	switch(cmd) {
+	case GEOMGETCONF:
+		error = g_ctl_ioctl_getconf(dev, cmd, data, fflag, td);
+		break;
+	default:
+		error = ENOTTY;
+		break;
+	}
+	g_topology_unlock();
+	PICKUP_GIANT();
+	return (error);
+
+}