4 files changed, 56 insertions, 58 deletions

diff --git a/sys/i386/isa/diskslice_machdep.c b/sys/i386/isa/diskslice_machdep.c
index 6c788a60eada..943ef5a27f2e 100644
--- a/sys/i386/isa/diskslice_machdep.c
+++ b/sys/i386/isa/diskslice_machdep.c
@@ -35,10 +35,9 @@
  *
  *	from: @(#)ufs_disksubr.c	7.16 (Berkeley) 5/4/91
  *	from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $
- *	$Id: diskslice_machdep.c,v 1.27 1997/12/02 21:06:20 phk Exp $
+ *	$Id: diskslice_machdep.c,v 1.28 1998/07/11 07:45:35 bde Exp $
  */
 
-#include <stddef.h>
 #include <sys/param.h>
 #include <sys/buf.h>
 #include <sys/conf.h>
@@ -174,21 +173,6 @@ dsinit(dname, dev, strat, lp, sspp)
 	struct diskslice *sp;
 	struct diskslices *ssp;
 
-	/*
-	 * Allocate a dummy slices "struct" and initialize it to contain
-	 * only an empty compatibility slice (pointing to itself) and a
-	 * whole disk slice (covering the disk as described by the label).
-	 * If there is an error, then the dummy struct becomes final.
-	 */
-	ssp = malloc(offsetof(struct diskslices, dss_slices)
-		     + BASE_SLICE * sizeof *sp, M_DEVBUF, M_WAITOK);
-	*sspp = ssp;
-	ssp->dss_first_bsd_slice = COMPATIBILITY_SLICE;
-	ssp->dss_nslices = BASE_SLICE;
-	sp = &ssp->dss_slices[0];
-	bzero(sp, BASE_SLICE * sizeof *sp);
-	sp[WHOLE_DISK_SLICE].ds_size = lp->d_secperunit;
-
 	mbr_offset = DOSBBSECTOR;
 reread_mbr:
 	/* Read master boot record. */
@@ -315,21 +299,18 @@ reread_mbr:
 	}
 
 	/*
-	 * Free the dummy slices "struct" and allocate a real new one.
-	 * Initialize special slices as above.
+	 * We are passed a pointer to a suitably initialized minimal
+	 * slices "struct" with no dangling pointers in it.  Replace it
+	 * by a maximal one.  This usually oversizes the "struct", but
+	 * enlarging it while searching for logical drives would be
+	 * inconvenient.
 	 */
-	free(ssp, M_DEVBUF);
-	ssp = malloc(offsetof(struct diskslices, dss_slices)
-#define	MAX_SLICES_SUPPORTED	MAX_SLICES  /* was (BASE_SLICE + NDOSPART) */
-		     + MAX_SLICES_SUPPORTED * sizeof *sp, M_DEVBUF, M_WAITOK);
+	free(*sspp, M_DEVBUF);
+	ssp = dsmakeslicestruct(MAX_SLICES, lp);
 	*sspp = ssp;
-	ssp->dss_first_bsd_slice = COMPATIBILITY_SLICE;
-	sp = &ssp->dss_slices[0];
-	bzero(sp, MAX_SLICES_SUPPORTED * sizeof *sp);
-	sp[WHOLE_DISK_SLICE].ds_size = lp->d_secperunit;
 
 	/* Initialize normal slices. */
-	sp += BASE_SLICE;
+	sp = &ssp->dss_slices[BASE_SLICE];
 	for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) {
 		sp->ds_offset = mbr_offset + dp->dp_start;
 		sp->ds_size = dp->dp_size;
diff --git a/sys/kern/subr_diskmbr.c b/sys/kern/subr_diskmbr.c
index 6c788a60eada..943ef5a27f2e 100644
--- a/sys/kern/subr_diskmbr.c
+++ b/sys/kern/subr_diskmbr.c
@@ -35,10 +35,9 @@
  *
  *	from: @(#)ufs_disksubr.c	7.16 (Berkeley) 5/4/91
  *	from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $
- *	$Id: diskslice_machdep.c,v 1.27 1997/12/02 21:06:20 phk Exp $
+ *	$Id: diskslice_machdep.c,v 1.28 1998/07/11 07:45:35 bde Exp $
  */
 
-#include <stddef.h>
 #include <sys/param.h>
 #include <sys/buf.h>
 #include <sys/conf.h>
@@ -174,21 +173,6 @@ dsinit(dname, dev, strat, lp, sspp)
 	struct diskslice *sp;
 	struct diskslices *ssp;
 
-	/*
-	 * Allocate a dummy slices "struct" and initialize it to contain
-	 * only an empty compatibility slice (pointing to itself) and a
-	 * whole disk slice (covering the disk as described by the label).
-	 * If there is an error, then the dummy struct becomes final.
-	 */
-	ssp = malloc(offsetof(struct diskslices, dss_slices)
-		     + BASE_SLICE * sizeof *sp, M_DEVBUF, M_WAITOK);
-	*sspp = ssp;
-	ssp->dss_first_bsd_slice = COMPATIBILITY_SLICE;
-	ssp->dss_nslices = BASE_SLICE;
-	sp = &ssp->dss_slices[0];
-	bzero(sp, BASE_SLICE * sizeof *sp);
-	sp[WHOLE_DISK_SLICE].ds_size = lp->d_secperunit;
-
 	mbr_offset = DOSBBSECTOR;
 reread_mbr:
 	/* Read master boot record. */
@@ -315,21 +299,18 @@ reread_mbr:
 	}
 
 	/*
-	 * Free the dummy slices "struct" and allocate a real new one.
-	 * Initialize special slices as above.
+	 * We are passed a pointer to a suitably initialized minimal
+	 * slices "struct" with no dangling pointers in it.  Replace it
+	 * by a maximal one.  This usually oversizes the "struct", but
+	 * enlarging it while searching for logical drives would be
+	 * inconvenient.
 	 */
-	free(ssp, M_DEVBUF);
-	ssp = malloc(offsetof(struct diskslices, dss_slices)
-#define	MAX_SLICES_SUPPORTED	MAX_SLICES  /* was (BASE_SLICE + NDOSPART) */
-		     + MAX_SLICES_SUPPORTED * sizeof *sp, M_DEVBUF, M_WAITOK);
+	free(*sspp, M_DEVBUF);
+	ssp = dsmakeslicestruct(MAX_SLICES, lp);
 	*sspp = ssp;
-	ssp->dss_first_bsd_slice = COMPATIBILITY_SLICE;
-	sp = &ssp->dss_slices[0];
-	bzero(sp, MAX_SLICES_SUPPORTED * sizeof *sp);
-	sp[WHOLE_DISK_SLICE].ds_size = lp->d_secperunit;
 
 	/* Initialize normal slices. */
-	sp += BASE_SLICE;
+	sp = &ssp->dss_slices[BASE_SLICE];
 	for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) {
 		sp->ds_offset = mbr_offset + dp->dp_start;
 		sp->ds_size = dp->dp_size;
diff --git a/sys/kern/subr_diskslice.c b/sys/kern/subr_diskslice.c
index 4dc234350eaa..a0e09cf43706 100644
--- a/sys/kern/subr_diskslice.c
+++ b/sys/kern/subr_diskslice.c
@@ -43,11 +43,13 @@
  *	from: wd.c,v 1.55 1994/10/22 01:57:12 phk Exp $
  *	from: @(#)ufs_disksubr.c	7.16 (Berkeley) 5/4/91
  *	from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $
- *	$Id: subr_diskslice.c,v 1.48 1998/07/11 07:45:42 bde Exp $
+ *	$Id: subr_diskslice.c,v 1.49 1998/07/20 12:37:59 bde Exp $
  */
 
 #include "opt_devfs.h"
 
+#include <stddef.h>
+
 #include <sys/param.h>
 #include <sys/buf.h>
 #include <sys/conf.h>
@@ -556,6 +558,32 @@ dsisopen(ssp)
 	return (0);
 }
 
+/*
+ * Allocate a slices "struct" and initialize it to contain only an empty
+ * compatibility slice (pointing to itself), a whole disk slice (covering
+ * the disk as described by the label), and (nslices - BASE_SLICES) empty
+ * slices beginning at BASE_SLICE.
+ */
+struct diskslices *
+dsmakeslicestruct(nslices, lp)
+	int nslices;
+	struct disklabel *lp;
+{
+	struct diskslice *sp;
+	struct diskslices *ssp;
+
+	ssp = malloc(offsetof(struct diskslices, dss_slices) +
+		     nslices * sizeof *sp, M_DEVBUF, M_WAITOK);
+	ssp->dss_bdevsw = NULL;
+	ssp->dss_cdevsw = NULL;
+	ssp->dss_first_bsd_slice = COMPATIBILITY_SLICE;
+	ssp->dss_nslices = nslices;
+	sp = &ssp->dss_slices[0];
+	bzero(sp, nslices * sizeof *sp);
+	sp[WHOLE_DISK_SLICE].ds_size = lp->d_secperunit;
+	return (ssp);
+}
+
 char *
 dsname(dname, unit, slice, part, partname)
 	char	*dname;
@@ -623,6 +651,13 @@ dsopen(dname, dev, mode, sspp, lp, strat, setgeom, bdevsw, cdevsw)
 	if (ssp != NULL && need_init)
 		dsgone(sspp);
 	if (need_init) {
+		/*
+		 * Allocate a minimal slices "struct".  This will become
+		 * the final slices "struct" if we don't want real slices
+		 * or if we can't find any real slices.
+		 */
+		*sspp = dsmakeslicestruct(BASE_SLICE, lp);
+
 		TRACE(("dsinit\n"));
 		error = dsinit(dname, dev, strat, lp, sspp);
 		if (error != 0) {
diff --git a/sys/sys/diskslice.h b/sys/sys/diskslice.h
index a7cac6cbb182..31b1219df1ea 100644
--- a/sys/sys/diskslice.h
+++ b/sys/sys/diskslice.h
@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: diskslice.h,v 1.22 1998/06/06 02:32:51 bde Exp $
+ *	$Id: diskslice.h,v 1.23 1998/07/04 22:30:26 julian Exp $
  */
 
 #ifndef	_SYS_DISKSLICE_H_
@@ -96,6 +96,7 @@ int	dsioctl __P((char *dname, dev_t dev, int cmd, caddr_t data, int flags,
 		     struct diskslices **sspp, void (*strat)(struct buf *bp),
 		     ds_setgeom_t *setgeom));
 int	dsisopen __P((struct diskslices *ssp));
+struct diskslices *dsmakeslicestruct __P((int nslices, struct disklabel *lp));
 char	*dsname __P((char *dname, int unit, int slice, int part,
 		     char *partname));
 int	dsopen __P((char *dname, dev_t dev, int mode, struct diskslices **sspp,