First commit of the GEOM subsystem to make it easier for people to

test and play with this.

This is not yet production quality and should be run only on dedicated
test boxes.

For people who want to develop transformations for GEOM there exist a
set of shims to run geom in userland (ask phk@freebsd.org).

Reports of all kinds to: phk@freebsd.org
Please include in report:
        dmesg
        sysctl debug.geomdot
        sysctl debug.geomconf

Known significant limitations:
        no kernel dump facility.
        ioctls severely restricted.

Sponsored by:   DARPA, NAI Labs

1 files changed, 278 insertions, 0 deletions

diff --git a/sys/geom/geom_slice.c b/sys/geom/geom_slice.c
new file mode 100644
index 0000000..36b0bd4
--- /dev/null
+++ b/sys/geom/geom_slice.c
@@ -0,0 +1,278 @@
+/*-
+ * 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 <sys/param.h>
+#ifndef _KERNEL
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <err.h>
+#else
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/bio.h>
+#include <sys/sysctl.h>
+#include <sys/proc.h>
+#include <sys/kthread.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#endif
+#include <sys/errno.h>
+#include <sys/sbuf.h>
+#include <geom/geom.h>
+#include <geom/geom_slice.h>
+#include <machine/stdarg.h>
+
+struct g_slicer *
+g_slice_init(unsigned nslice, unsigned scsize)
+{
+	struct g_slicer *gsp;
+
+	gsp = g_malloc(sizeof *gsp + nslice * sizeof(struct g_slice) + scsize,
+	    M_WAITOK | M_ZERO);
+	gsp->softc = gsp + 1;
+	gsp->slices = (struct g_slice *)((u_char *)gsp->softc + scsize);
+	gsp->nslice = nslice;
+	return (gsp);
+}
+
+int
+g_slice_access(struct g_provider *pp, int dr, int dw, int de)
+{
+	int error, i;
+	struct g_geom *gp;
+	struct g_consumer *cp;
+	struct g_provider *pp2;
+	struct g_slicer *gsp;
+	struct g_slice *gsl, *gsl2;
+
+	gp = pp->geom;
+	cp = LIST_FIRST(&gp->consumer);
+	KASSERT (cp != NULL, ("g_slice_access but no consumer"));
+	gsp = gp->softc;
+	gsl = &gsp->slices[pp->index];
+	for (i = 0; i < gsp->nslice; i++) {
+		gsl2 = &gsp->slices[i];
+		if (gsl2->length == 0)
+			continue;
+		if (i == pp->index)
+			continue;
+		if (gsl->offset + gsl->length <= gsl2->offset)
+			continue;
+		if (gsl2->offset + gsl2->length <= gsl->offset)
+			continue;
+		/* overlap */
+		pp2 = gsl2->provider;
+		if ((pp->acw + dw) > 0 && pp2->ace > 0)
+			return (EPERM);
+		if ((pp->ace + de) > 0 && pp2->acw > 0)
+			return (EPERM);
+	}
+	/* On first open, grab an extra "exclusive" bit */
+	if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
+		de++;
+	/* ... and let go of it on last close */
+	if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1)
+		de--;
+	error = g_access_rel(cp, dr, dw, de);
+	return (error);
+}
+
+void
+g_slice_start(struct bio *bp)
+{
+	struct bio *bp2;
+	struct g_provider *pp;
+	struct g_geom *gp;
+	struct g_consumer *cp;
+	struct g_slicer *gsp;
+	struct g_slice *gsl;
+	int index;
+
+	pp = bp->bio_to;
+	gp = pp->geom;
+	gsp = gp->softc;
+	cp = LIST_FIRST(&gp->consumer);
+	index = pp->index;
+	switch(bp->bio_cmd) {
+	case BIO_READ:
+	case BIO_WRITE:
+	case BIO_DELETE:
+		gsl = &gsp->slices[index];
+		if (bp->bio_offset > gsl->length) {
+			bp->bio_error = EINVAL; /* XXX: EWHAT ? */
+			g_io_deliver(bp);
+			return;
+		}
+		bp2 = g_clone_bio(bp);
+		if (bp2->bio_offset + bp2->bio_length > gsl->length)
+			bp2->bio_length = gsl->length - bp2->bio_offset;
+		bp2->bio_done = g_std_done;
+		bp2->bio_offset += gsl->offset;
+		g_io_request(bp2, cp);
+		return;
+	case BIO_GETATTR:
+	case BIO_SETATTR:
+		if (g_haveattr_off_t(bp, "GEOM::mediasize",
+		    gsp->slices[index].length))
+			return;
+		if (gsp->start(bp))
+			return;
+		bp2 = g_clone_bio(bp);
+		bp2->bio_done = g_std_done;
+		g_io_request(bp2, cp);
+		break;
+	default:
+		bp->bio_error = EOPNOTSUPP;
+		g_io_deliver(bp);
+		return;
+	}
+}
+
+void
+g_slice_dumpconf(struct sbuf *sb, char *indent, struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp)
+{
+	struct g_mbr_softc *mp;
+	struct g_slicer *gsp;
+
+	gsp = gp->softc;
+	mp = gsp->softc;
+	if (pp != NULL) {
+		sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index);
+		sbuf_printf(sb, "%s<length>%llu</length>\n",
+		    indent, gsp->slices[pp->index].length);
+		sbuf_printf(sb, "%s<seclength>%llu</seclength>\n",
+		    indent, gsp->slices[pp->index].length / 512);
+		sbuf_printf(sb, "%s<offset>%llu</offset>\n",
+		    indent, gsp->slices[pp->index].offset);
+		sbuf_printf(sb, "%s<secoffset>%llu</secoffset>\n",
+		    indent, gsp->slices[pp->index].offset / 512);
+	}
+}
+
+struct g_provider *
+g_slice_addslice(struct g_geom *gp, int index, off_t offset, off_t length, char *fmt, ...)
+{
+	struct g_provider *pp;
+	struct g_slicer *gsp;
+	va_list ap;
+	struct sbuf *sb;
+
+	g_trace(G_T_TOPOLOGY, "g_slice_addslice()");
+	g_topology_lock();
+	gsp = gp->softc;
+	va_start(ap, fmt);
+	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
+	sbuf_vprintf(sb, fmt, ap);
+	sbuf_finish(sb);
+	pp = g_new_providerf(gp, sbuf_data(sb));
+
+	pp->index = index;
+	gsp->slices[index].length = length;
+	gsp->slices[index].offset = offset;
+	gsp->slices[index].provider = pp;
+	sbuf_delete(sb);
+	g_topology_unlock();
+	return(pp);
+}
+
+struct g_geom *
+g_slice_new(struct g_method *mp, int slices, struct g_provider *pp, struct g_consumer **cpp, void *extrap, int extra, g_slice_start_t *start)
+{
+	struct g_geom *gp;
+	struct g_slicer *gsp;
+	struct g_consumer *cp;
+	void **vp;
+	int error;
+
+	g_topology_assert();
+	vp = (void **)extrap;
+	gp = g_new_geomf(mp, "%s", pp->name);
+	gsp = g_slice_init(slices, extra);
+	gsp->start = start;
+	gp->softc = gsp;
+	gp->start = g_slice_start;
+	gp->spoiled = g_std_spoiled;
+	gp->dumpconf = g_slice_dumpconf;
+	cp = g_new_consumer(gp);
+	g_attach(cp, pp);
+	error = g_access_rel(cp, 1, 0, 0);
+	if (error) {
+		g_dettach(cp);
+		g_destroy_consumer(cp);
+		g_free(gp->softc);
+		g_destroy_geom(gp);
+		return (NULL);
+	}
+	*vp = gsp->softc;
+	*cpp = cp;
+	return (gp);
+}
+
+void
+g_slice_orphan(struct g_consumer *cp, struct thread *tp __unused)
+{
+	struct g_geom *gp;
+	struct g_provider *pp;
+	int error;
+
+	g_trace(G_T_TOPOLOGY, "g_slice_orphan(%p/%s)", cp, cp->provider->name);
+	g_topology_assert();
+	KASSERT(cp->provider->error != 0,
+	    ("g_slice_orphan with error == 0"));
+
+	gp = cp->geom;
+	gp->flags |= G_GEOM_WITHER;
+	/* First prevent any new requests */
+	error = cp->provider->error;
+	LIST_FOREACH(pp, &gp->provider, provider)
+		g_orphan_provider(pp, error);
+
+	return;
+	if (cp->biocount > 0)
+		return;
+
+	/* Then selfdestruct */
+	if (cp->acr != 0 || cp->acw != 0 || cp->ace != 0)
+		g_access_abs(cp, 0, 0, 0);
+	g_dettach(cp);
+	g_destroy_consumer(cp);
+	return;
+}