Functions to encode and decode Sun Microsystems disk partitioning data

structures.

Mostly by:	jake

1 files changed, 131 insertions, 0 deletions

diff --git a/sys/geom/geom_sunlabel_enc.c b/sys/geom/geom_sunlabel_enc.c
new file mode 100644
index 0000000..afa3e0b
--- /dev/null
+++ b/sys/geom/geom_sunlabel_enc.c
@@ -0,0 +1,131 @@
+/*-
+ * Copyright (c) 2003 Jake Burkholder
+ * Copyright (c) 2003 Poul-Henning Kamp
+ * 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 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.
+ *
+ * $FreeBSD$
+ *
+ * Functions to encode or decode struct sun_disklabel into a bytestream
+ * of correct endianess and packing.
+ *
+ * NB!  This file must be usable both in kernel and userland.
+ *
+ */
+
+#include <sys/types.h>
+#include <sys/endian.h>
+#include <sys/errno.h>
+#include <sys/sun_disklabel.h>
+
+#define	SL_TEXT		0x0
+#define	SL_TEXT_SIZEOF	0x80
+#define	SL_RPM		0x1a4
+#define	SL_PCYLINDERS	0x1a6
+#define	SL_SPARESPERCYL	0x1a8
+#define	SL_INTERLEAVE	0x1ae
+#define	SL_NCYLINDERS	0x1b0
+#define	SL_ACYLINDERS	0x1b2
+#define	SL_NTRACKS	0x1b4
+#define	SL_NSECTORS	0x1b6
+#define	SL_PART		0x1bc
+#define	SL_MAGIC	0x1fc
+#define	SL_CKSUM	0x1fe
+
+#define	SL_LENGTH	0x200
+
+#define	SL_NPART	0x8
+
+#define	SDKP_CYLOFFSET	0
+#define	SDKP_NSECTORS	0x4
+#define	SDKP_SIZEOF	0x8
+
+/*
+ * Decode the relevant fields of a sun disk label, and return zero if the
+ * magic and checksum works out OK.
+ */
+int
+sunlabel_dec(void const *pp, struct sun_disklabel *sl)
+{
+	const uint8_t *p;
+	size_t i;
+	u_int u;
+
+	p = pp;
+	for (i = 0; i < sizeof(sl->sl_text); i++)
+		sl->sl_text[i] = p[SL_TEXT + i];
+	sl->sl_rpm = be16dec(p + SL_RPM);
+	sl->sl_pcylinders = be16dec(p + SL_PCYLINDERS);
+	sl->sl_sparespercyl = be16dec(p + SL_SPARESPERCYL);
+	sl->sl_interleave = be16dec(p + SL_INTERLEAVE);
+	sl->sl_ncylinders = be16dec(p + SL_NCYLINDERS);
+	sl->sl_acylinders = be16dec(p + SL_ACYLINDERS);
+	sl->sl_ntracks = be16dec(p + SL_NTRACKS);
+	sl->sl_nsectors = be16dec(p + SL_NSECTORS);
+	for (i = 0; i < SL_NPART; i++) {
+		sl->sl_part[i].sdkp_cyloffset = be32dec(p + SL_PART +
+		    (i * SDKP_SIZEOF) + SDKP_CYLOFFSET);
+		sl->sl_part[i].sdkp_nsectors = be32dec(p + SL_PART +
+		    (i * SDKP_SIZEOF) + SDKP_NSECTORS);
+	}
+	sl->sl_magic = be16dec(p + SL_MAGIC);
+	for (i = u = 0; i < SL_LENGTH; i += 2)
+		u ^= be16dec(p + i);
+	if (u == 0 && sl->sl_magic == SUN_DKMAGIC)
+		return (0);
+	else
+		return (EINVAL);
+}
+
+/*
+ * Encode the relevant fields into a sun disklabel, compute new checksum.
+ */
+void
+sunlabel_enc(void *pp, struct sun_disklabel *sl)
+{
+	uint8_t *p;
+	size_t i;
+	u_int u;
+
+	p = pp;
+	for (i = 0; i < SL_TEXT_SIZEOF; i++)
+		p[SL_TEXT + i] = sl->sl_text[i];
+	be16enc(p + SL_RPM, sl->sl_rpm);
+	be16enc(p + SL_PCYLINDERS, sl->sl_pcylinders);
+	be16enc(p + SL_SPARESPERCYL, sl->sl_sparespercyl);
+	be16enc(p + SL_INTERLEAVE, sl->sl_interleave);
+	be16enc(p + SL_NCYLINDERS, sl->sl_ncylinders);
+	be16enc(p + SL_ACYLINDERS, sl->sl_acylinders);
+	be16enc(p + SL_NTRACKS, sl->sl_ntracks);
+	be16enc(p + SL_NSECTORS, sl->sl_nsectors);
+	for (i = 0; i < SL_NPART; i++) {
+		be32enc(p + SL_PART + (i * SDKP_SIZEOF) + SDKP_CYLOFFSET,
+		    sl->sl_part[i].sdkp_cyloffset);
+		be32enc(p + SL_PART + (i * SDKP_SIZEOF) + SDKP_NSECTORS,
+		    sl->sl_part[i].sdkp_nsectors);
+	}
+	be16enc(p + SL_MAGIC, sl->sl_magic);
+	for (i = u = 0; i < SL_LENGTH; i += 2)
+		u ^= be16dec(p + i);
+	be16enc(p + SL_CKSUM, u);
+}