From 0c8fd0c8aceb9eefe954ce864679cf6c386d7b1a Mon Sep 17 00:00:00 2001
From: Alexander Motin <mav@FreeBSD.org>
Date: Wed, 6 Jan 2010 13:14:37 +0000
Subject: [PATCH] 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.
---
 sys/geom/geom_slice.c  | 8 ++++----
 sys/geom/part/g_part.c | 9 ++++-----
 sys/geom/uzip/g_uzip.c | 6 ++----
 3 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/sys/geom/geom_slice.c b/sys/geom/geom_slice.c
index 0bdb10c8222f..8a490180a68a 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 2b57a262edc8..0434ace0cfe1 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 90eee02f248f..2301efbe0e19 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);