Only attach to a GPT partition if it has the GPT_ENT_TYPE_FREEBSD type.

XXX: This only works currently with GEOM_GPT which only exists in 6.x.
XXX: I didn't add 'mbroffset' support for a GPT partition holding a BSD
label as I'm not sure if they use relative or absolute offsets.

MFC after:	3 days

1 files changed, 13 insertions, 0 deletions

diff --git a/sys/geom/geom_bsd.c b/sys/geom/geom_bsd.c
index 26252ab..1a0bf20 100644
--- a/sys/geom/geom_bsd.c
+++ b/sys/geom/geom_bsd.c
@@ -55,6 +55,8 @@ __FBSDID("$FreeBSD$");
 #include <sys/md5.h>
 #include <sys/errno.h>
 #include <sys/disklabel.h>
+#include <sys/gpt.h>
+#include <sys/uuid.h>
 #include <geom/geom.h>
 #include <geom/geom_slice.h>
 
@@ -461,6 +463,8 @@ g_bsd_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_
  * not implemented here.
  */
 
+static struct uuid freebsd_slice = GPT_ENT_TYPE_FREEBSD;
+
 static struct g_geom *
 g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags)
 {
@@ -472,6 +476,7 @@ g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags)
 	struct g_slicer *gsp;
 	u_char hash[16];
 	MD5_CTX md5sum;
+	struct uuid uuid;
 
 	g_trace(G_T_TOPOLOGY, "bsd_taste(%s,%s)", mp->name, pp->name);
 	g_topology_assert();
@@ -527,6 +532,14 @@ g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags)
 				break;
 		}
 
+		/* Same thing if we are inside a GPT */
+		error = g_getattr("GPT::type", cp, &uuid);
+		if (!error) {
+			if (memcmp(&uuid, &freebsd_slice, sizeof(uuid)) != 0 &&
+			    flags == G_TF_NORMAL)
+				break;
+		}
+
 		/* Get sector size, we need it to read data. */
 		secsize = cp->provider->sectorsize;
 		if (secsize < 512)