Module Name: src
Committed By: hauke
Date: Tue Jan 24 15:24:55 UTC 2012
Modified Files:
src/sys/arch/macppc/macppc: disksubr.c
Log Message:
Add support for BSD disklabels, scanning the beginning of the disk
in four-byte strides, like disklabel(8) does it.
Since the netbsd-6 branch is around the corner, this is a
minimally-intrusive addition.
Note there is no write support, for good reasons.
Note also that disksubr.c is in dire need of re-structuring.
To generate a diff of this commit:
cvs rdiff -u -r1.47 -r1.48 src/sys/arch/macppc/macppc/disksubr.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/macppc/macppc/disksubr.c
diff -u src/sys/arch/macppc/macppc/disksubr.c:1.47 src/sys/arch/macppc/macppc/disksubr.c:1.48
--- src/sys/arch/macppc/macppc/disksubr.c:1.47 Mon Mar 16 23:11:12 2009
+++ src/sys/arch/macppc/macppc/disksubr.c Tue Jan 24 15:24:55 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: disksubr.c,v 1.47 2009/03/16 23:11:12 dsl Exp $ */
+/* $NetBSD: disksubr.c,v 1.48 2012/01/24 15:24:55 hauke Exp $ */
/*
* Copyright (c) 1982, 1986, 1988 Regents of the University of California.
@@ -106,7 +106,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: disksubr.c,v 1.47 2009/03/16 23:11:12 dsl Exp $");
+__KERNEL_RCSID(0, "$NetBSD: disksubr.c,v 1.48 2012/01/24 15:24:55 hauke Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -137,6 +137,8 @@ static const char *read_mac_label(dev_t,
struct disklabel *, struct cpu_disklabel *);
static const char *read_dos_label(dev_t, void (*)(struct buf *),
struct disklabel *, struct cpu_disklabel *);
+static const char *read_bsd_label(dev_t, void (*)(struct buf *),
+ struct disklabel *, struct cpu_disklabel *);
static int get_netbsd_label(dev_t, void (*)(struct buf *),
struct disklabel *, struct cpu_disklabel *);
@@ -387,6 +389,78 @@ done:
return msg;
}
+/*
+ * Scan the disk buffer in four byte strides for a native BSD
+ * disklabel (different ports have variably-sized bootcode before
+ * the label)
+ */
+static const char *
+read_bsd_label(dev_t dev, void (*strat)(struct buf *), struct disklabel *lp,
+ struct cpu_disklabel *osdep)
+{
+ struct disklabel *dlp;
+ struct buf *bp;
+ const char *msg;
+ struct disklabel *blk_start, *blk_end;
+ int size, match;
+
+ msg = NULL;
+
+ /*
+ * Read in the first #(NUM_PARTS + 1) blocks of the disk.
+ * The native Macintosh partition table starts at
+ * sector #1, but we want #0 too for the BSD label.
+ */
+ size = roundup((NUM_PARTS + 1) << DEV_BSHIFT, lp->d_secsize);
+ bp = geteblk(size);
+
+ bp->b_dev = dev;
+ bp->b_blkno = 0;
+ bp->b_resid = 0;
+ bp->b_bcount = size;
+ bp->b_flags |= B_READ;
+ bp->b_cylinder = 1 / lp->d_secpercyl;
+ (*strat)(bp);
+
+ match = 0;
+
+ if (biowait(bp)) {
+ msg = "I/O error reading BSD disklabel";
+ } else {
+ /*
+ * Hunt the label, starting at the beginning of the disk.
+ * When we find an inconsistent label, report and continue.
+ */
+ blk_start = (struct disklabel *)bp->b_data;
+ blk_end = (struct disklabel *)((char *)bp->b_data +
+ (NUM_PARTS << DEV_BSHIFT) - sizeof(struct disklabel));
+
+ for (dlp = blk_start; dlp <= blk_end;
+ dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
+ if (dlp->d_magic == DISKMAGIC &&
+ dlp->d_magic2 == DISKMAGIC) {
+ /* Sanity check */
+ if (dlp->d_npartitions <= MAXPARTITIONS &&
+ dkcksum(dlp) == 0) {
+ *lp = *dlp;
+ match = -1;
+ break;
+#ifdef DIAGNOSTIC
+ } else {
+ printf("read_bsd_label() found "
+ "damaged disklabel starting at "
+ "0x0%p, ignore\n", dlp);
+#endif /* DIAGNOSTIC */
+ }
+ }
+ }
+ if (!match)
+ msg = "BSD disklabel not found";
+ }
+ brelse(bp, 0);
+ return msg;
+}
+
/* Read MS-DOS partition table.
*
* XXX -
@@ -597,8 +671,9 @@ readdisklabel(dev_t dev, void (*strat)(s
if (!msg)
osdep->cd_start = 0;
} else {
- msg = "no disk label -- NetBSD or Macintosh";
- osdep->cd_start = 0; /* XXX for now */
+ msg = read_bsd_label(dev, strat, lp, osdep);
+ if (!msg)
+ osdep->cd_start = 0; /* XXX for now */
}
}
