Change the registration of magic spaces so it does its own memory management.

Sponsored by: DARPA & NAI Labs.

sys/geom/geom.h

@@ -197,6 +197,7 @@ struct g_magicspaces {
 	uintptr_t		geom_id;
 	char			class[8];
 	uint			nmagic;
+	uint			nspace;
 	struct g_magicspace	*magicspace;
 };
 
@@ -223,7 +224,7 @@ void g_silence(void);
 int g_access_abs(struct g_consumer *cp, int read, int write, int exclusive);
 int g_access_rel(struct g_consumer *cp, int read, int write, int exclusive);
 void g_add_class(struct g_class *mp);
-int g_add_magicspace(struct g_geom *gp, u_int index, const char *name, off_t start, u_int len, u_int flags);
+int g_add_magicspace(struct g_geom *gp, const char *name, off_t start, u_int len, u_int flags);
 int g_attach(struct g_consumer *cp, struct g_provider *pp);
 struct g_geom *g_create_geomf(char *class, struct g_provider *, char *fmt, ...);
 void g_destroy_consumer(struct g_consumer *cp);
@@ -239,7 +240,6 @@ int g_haveattr_off_t(struct bio *bp, char *attribute, off_t val);
 struct g_geom * g_insert_geom(char *class, struct g_consumer *cp);
 struct g_consumer * g_new_consumer(struct g_geom *gp);
 struct g_geom * g_new_geomf(struct g_class *mp, char *fmt, ...);
-int g_new_magicspaces(struct g_geom *gp, int nspaces);
 struct g_provider * g_new_providerf(struct g_geom *gp, char *fmt, ...);
 void g_sanity(void *ptr);
 void g_spoil(struct g_provider *pp, struct g_consumer *cp);

sys/geom/geom_bsd.c

@@ -339,19 +339,17 @@ g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags)
 		}
 		error = g_bsd_try(gsp, cp, secsize, ms, secsize);
 		if (!error) {
-			g_new_magicspaces(gp, 4);
+			g_add_magicspace(gp, "boot1",     0, 512, 0);
-			g_add_magicspace(gp, 0, "boot1",     0, 512, 0);
+			g_add_magicspace(gp, "label",   512, 276, 0);
-			g_add_magicspace(gp, 1, "label",   512, 276, 0);
+			g_add_magicspace(gp, "fill0",   748, 236, 0);
-			g_add_magicspace(gp, 2, "fill0",   748, 236, 0);
+			g_add_magicspace(gp, "boot2", 1024, 7168, 0);
-			g_add_magicspace(gp, 3, "boot2", 1024, 7168, 0);
 		}
 		if (error) {
 			error = g_bsd_try(gsp, cp, secsize, ms, 64);
 			if (!error) {
-				g_new_magicspaces(gp, 3);
+				g_add_magicspace(gp, "fill0",     0,  64, 0);
-				g_add_magicspace(gp, 0, "fill0",     0,  64, 0);
+				g_add_magicspace(gp, "label",    64, 276, 0);
-				g_add_magicspace(gp, 1, "label",    64, 276, 0);
+				g_add_magicspace(gp, "fill1",   340, 172, 0);
-				g_add_magicspace(gp, 2, "fill1",   340, 172, 0);
 			}
 		}
 		if (error)

sys/geom/geom_mbr.c

@@ -251,10 +251,9 @@ g_mbr_taste(struct g_class *mp, struct g_provider *pp, int insist)
 	g_topology_lock();
 	error = g_access_rel(cp, -1, 0, 0);
 	if (npart > 0) {
-		g_new_magicspaces(gp, 3);
+		g_add_magicspace(gp, "boot", 0, DOSPARTOFF, 0);
-		g_add_magicspace(gp, 0, "boot", 0, DOSPARTOFF, 0);
+		g_add_magicspace(gp, "mbr", DOSPARTOFF, 4 * 16, 0);
-		g_add_magicspace(gp, 1, "mbr", DOSPARTOFF, 4 * 16, 0);
+		g_add_magicspace(gp, "magic", 510, 2, 0);
-		g_add_magicspace(gp, 2, "signature", 510, 2, 0);
 		LIST_FOREACH(pp, &gp->provider, provider)
 			g_error_provider(pp, 0);
 		return (gp);

sys/geom/geom_subr.c

@@ -114,28 +114,39 @@ g_new_geomf(struct g_class *mp, char *fmt, ...)
 	return (gp);
 }
 
-int
+/*
-g_new_magicspaces(struct g_geom *gp, int nspaces)
+ * Add a magic space to a geom.  There is no locking here because nobody
-{
+ * should be modifying these except the geom itself during configuration,
-	gp->magicspaces = g_malloc(sizeof *gp->magicspaces, M_WAITOK | M_ZERO);
+ * so it cannot go away while we fiddling it.
-	gp->magicspaces->magicspace =
+ * For now, no provision exists for removing magic spaces or for changing
-	    g_malloc(sizeof *gp->magicspaces->magicspace * nspaces,
+ * them on the fly.
-	    M_WAITOK | M_ZERO);
+ */
-	gp->magicspaces->geom_id = (uintptr_t)gp;
-	strncpy(gp->magicspaces->class, gp->class->name,
-	    sizeof gp->magicspaces->class);
-	gp->magicspaces->nmagic = nspaces;
-	return (0);
-}
 
 int
-g_add_magicspace(struct g_geom *gp, u_int index, const char *name, off_t start, u_int len, u_int flags)
+g_add_magicspace(struct g_geom *gp, const char *name, off_t start, u_int len, u_int flags)
 {
-	struct g_magicspace *msp;
+	int i;
+	struct g_magicspaces *msps;
+	struct g_magicspace *msp, *msp2;
 
-	/* KASSERT gp->magicspaces != NULL */
+	if (gp->magicspaces == NULL) {
-	/* KASSERT index < gp->magicspaces->nmagic */
+		msps = g_malloc(sizeof *gp->magicspaces, M_WAITOK | M_ZERO);
-	msp = &gp->magicspaces->magicspace[index];
+		msps->geom_id = (uintptr_t)gp;
+		strncpy(msps->class, gp->class->name, sizeof msps->class);
+		gp->magicspaces = msps;
+	}
+	msps = gp->magicspaces;
+	if (msps->nmagic >= msps->nspace) {
+		i = msps->nspace + 1;
+		msp = g_malloc(sizeof(*msp) * i, M_WAITOK | M_ZERO);
+		bcopy(msps->magicspace, msp, sizeof(*msp) * msps->nmagic);
+		msp2 = msps->magicspace;
+		msps->magicspace = msp;
+		if (msp2 != NULL)
+			g_free(msp2);
+		msps->nspace = i;
+	}
+	msp = &msps->magicspace[msps->nmagic++];
 	strncpy(msp->name, name, sizeof msp->name);
 	msp->offset = start;
 	msp->len = len;

sys/geom/geom_sunlabel.c

@@ -180,8 +180,7 @@ g_sunlabel_taste(struct g_class *mp, struct g_provider *pp, int flags)
 	g_topology_lock();
 	error = g_access_rel(cp, -1, 0, 0);
 	if (npart > 0) {
-		g_new_magicspaces(gp, 1);
+		g_add_magicspace(gp, "label", 0, 512, 0);
-		g_add_magicspace(gp, 0, "label", 0, 512, 0);
 		return (gp);
 	}
 	g_std_spoiled(cp);