Change the way in which zero stripesize is handled. Instead of reporting

zero stripeoffset in such case (as if device has no stripes), report offset
from the beginning of the media (as if device has single infinite stripe).

This gives partitioning tools information, required to guess better
partition alignment, in case if hardware doesn't report it's stripe size.
For example, it should give disklabel info about odd offset made by fdisk.

3 files changed, 10 insertions, 13 deletions

diff --git a/sys/geom/geom_slice.c b/sys/geom/geom_slice.c
index 0bdb10c..8a49018 100644
--- a/sys/geom/geom_slice.c
+++ b/sys/geom/geom_slice.c
@@ -393,10 +393,10 @@ g_slice_config(struct g_geom *gp, u_int idx, int how, off_t offset, off_t length
 	pp = g_new_providerf(gp, sbuf_data(sb));
 	pp2 = LIST_FIRST(&gp->consumer)->provider;
 	pp->flags = pp2->flags & G_PF_CANDELETE;
-	if (pp2->stripesize > 0) {
-		pp->stripesize = pp2->stripesize;
-		pp->stripeoffset = (pp2->stripeoffset + offset) % pp->stripesize;
-	}
+	pp->stripesize = pp2->stripesize;
+	pp->stripeoffset = pp2->stripeoffset + offset;
+	if (pp->stripesize > 0)
+		pp->stripeoffset %= pp->stripesize;
 	if (0 && bootverbose)
 		printf("GEOM: Configure %s, start %jd length %jd end %jd\n",
 		    pp->name, (intmax_t)offset, (intmax_t)length,
diff --git a/sys/geom/part/g_part.c b/sys/geom/part/g_part.c
index 2b57a26..0434ace 100644
--- a/sys/geom/part/g_part.c
+++ b/sys/geom/part/g_part.c
@@ -288,11 +288,10 @@ g_part_new_provider(struct g_geom *gp, struct g_part_table *table,
 	entry->gpe_pp->mediasize -= entry->gpe_offset - offset;
 	entry->gpe_pp->sectorsize = pp->sectorsize;
 	entry->gpe_pp->flags = pp->flags & G_PF_CANDELETE;
-	if (pp->stripesize > 0) {
-		entry->gpe_pp->stripesize = pp->stripesize;
-		entry->gpe_pp->stripeoffset = (pp->stripeoffset +
-		    entry->gpe_offset) % pp->stripesize;
-	}
+	entry->gpe_pp->stripesize = pp->stripesize;
+	entry->gpe_pp->stripeoffset = pp->stripeoffset + entry->gpe_offset;
+	if (pp->stripesize > 0)
+		entry->gpe_pp->stripeoffset %= pp->stripesize;
 	g_error_provider(entry->gpe_pp, 0);
 }
 
diff --git a/sys/geom/uzip/g_uzip.c b/sys/geom/uzip/g_uzip.c
index 90eee02..2301efb 100644
--- a/sys/geom/uzip/g_uzip.c
+++ b/sys/geom/uzip/g_uzip.c
@@ -467,10 +467,8 @@ g_uzip_taste(struct g_class *mp, struct g_provider *pp, int flags)
 	pp2->sectorsize = 512;
 	pp2->mediasize = (off_t)sc->nblocks * sc->blksz;
         pp2->flags = pp->flags & G_PF_CANDELETE;
-        if (pp->stripesize > 0) {
-                pp2->stripesize = pp->stripesize;
-                pp2->stripeoffset = pp->stripeoffset;
-        }
+        pp2->stripesize = pp->stripesize;
+        pp2->stripeoffset = pp->stripeoffset;
 	g_error_provider(pp2, 0);
 	g_access(cp, -1, 0, 0);