MFC r258357:

  Add "resize" verb to gmirror(8) and such functionality to geom_mirror(4).
  Now it is easy to expand the size of the mirror when all its components
  are replaced. Also add g_resize method to geom_mirror class. It will write
  updated metadata to new last sector, when parent provider is resized.

2 files changed, 118 insertions, 1 deletions

diff --git a/sbin/geom/class/mirror/geom_mirror.c b/sbin/geom/class/mirror/geom_mirror.c
index 9f0acc6..17cfccb 100644
--- a/sbin/geom/class/mirror/geom_mirror.c
+++ b/sbin/geom/class/mirror/geom_mirror.c
@@ -28,6 +28,7 @@
 __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
+#include <err.h>
 #include <errno.h>
 #include <paths.h>
 #include <stdio.h>
@@ -53,6 +54,7 @@ static void mirror_activate(struct gctl_req *req);
 static void mirror_clear(struct gctl_req *req);
 static void mirror_dump(struct gctl_req *req);
 static void mirror_label(struct gctl_req *req);
+static void mirror_resize(struct gctl_req *req, unsigned flags);
 
 struct g_command class_commands[] = {
 	{ "activate", G_FLAG_VERBOSE, mirror_main, G_NULL_OPTS,
@@ -112,6 +114,13 @@ struct g_command class_commands[] = {
 	{ "remove", G_FLAG_VERBOSE, NULL, G_NULL_OPTS,
 	    "[-v] name prov ..."
 	},
+	{ "resize", G_FLAG_VERBOSE, mirror_resize,
+	    {
+		{ 's', "size", "*", G_TYPE_STRING },
+		G_OPT_SENTINEL
+	    },
+	    "[-s size] [-v] name"
+	},
 	{ "stop", G_FLAG_VERBOSE, NULL,
 	    {
 		{ 'f', "force", NULL, G_TYPE_BOOL },
@@ -376,3 +385,96 @@ mirror_activate(struct gctl_req *req)
 			printf("Provider %s activated.\n", path);
 	}
 }
+
+static struct gclass *
+find_class(struct gmesh *mesh, const char *name)
+{
+	struct gclass *classp;
+
+	LIST_FOREACH(classp, &mesh->lg_class, lg_class) {
+		if (strcmp(classp->lg_name, name) == 0)
+			return (classp);
+	}
+	return (NULL);
+}
+
+static struct ggeom *
+find_geom(struct gclass *classp, const char *name)
+{
+	struct ggeom *gp;
+
+	LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
+		if (strcmp(gp->lg_name, name) == 0)
+			return (gp);
+	}
+	return (NULL);
+}
+
+static void
+mirror_resize(struct gctl_req *req, unsigned flags __unused)
+{
+	struct gmesh mesh;
+	struct gclass *classp;
+	struct ggeom *gp;
+	struct gprovider *pp;
+	struct gconsumer *cp;
+	off_t size;
+	int error, nargs;
+	const char *name;
+	char ssize[30];
+
+	nargs = gctl_get_int(req, "nargs");
+	if (nargs < 1) {
+		gctl_error(req, "Too few arguments.");
+		return;
+	}
+	error = geom_gettree(&mesh);
+	if (error)
+		errc(EXIT_FAILURE, error, "Cannot get GEOM tree");
+	name = gctl_get_ascii(req, "class");
+	if (name == NULL)
+		abort();
+	classp = find_class(&mesh, name);
+	if (classp == NULL)
+		errx(EXIT_FAILURE, "Class %s not found.", name);
+	name = gctl_get_ascii(req, "arg0");
+	if (name == NULL)
+		abort();
+	gp = find_geom(classp, name);
+	if (gp == NULL)
+		errx(EXIT_FAILURE, "No such geom: %s.", name);
+	pp = LIST_FIRST(&gp->lg_provider);
+	if (pp == NULL)
+		errx(EXIT_FAILURE, "Provider of geom %s not found.", name);
+	size = pp->lg_mediasize;
+	name = gctl_get_ascii(req, "size");
+	if (name == NULL)
+		errx(EXIT_FAILURE, "The size is not specified.");
+	if (*name == '*') {
+#define	CSZ(c)	((c)->lg_provider->lg_mediasize - \
+    (c)->lg_provider->lg_sectorsize)
+		/* Find the maximum possible size */
+		LIST_FOREACH(cp, &gp->lg_consumer, lg_consumer) {
+			if (CSZ(cp) > size)
+				size = CSZ(cp);
+		}
+		LIST_FOREACH(cp, &gp->lg_consumer, lg_consumer) {
+			if (CSZ(cp) < size)
+				size = CSZ(cp);
+		}
+#undef CSZ
+		if (size == pp->lg_mediasize)
+			errx(EXIT_FAILURE,
+			    "Cannot expand provider %s\n",
+			    pp->lg_name);
+	} else {
+		error = g_parse_lba(name, pp->lg_sectorsize, &size);
+		if (error)
+			errc(EXIT_FAILURE, error, "Invalid size param");
+		size *= pp->lg_sectorsize;
+	}
+	snprintf(ssize, sizeof(ssize), "%ju", (uintmax_t)size);
+	gctl_change_param(req, "size", -1, ssize);
+	geom_deletetree(&mesh);
+	gctl_issue(req);
+}
diff --git a/sbin/geom/class/mirror/gmirror.8 b/sbin/geom/class/mirror/gmirror.8
index 58ff8af..cabeac6 100644
--- a/sbin/geom/class/mirror/gmirror.8
+++ b/sbin/geom/class/mirror/gmirror.8
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd December 8, 2009
+.Dd November 20, 2013
 .Dt GMIRROR 8
 .Os
 .Sh NAME
@@ -60,6 +60,11 @@
 .Ar name
 .Ar prov ...
 .Nm
+.Cm resize
+.Op Fl v
+.Op Fl s Ar size
+.Ar name
+.Nm
 .Cm insert
 .Op Fl hiv
 .Op Fl p Ar priority
@@ -193,6 +198,16 @@ balance algorithm.
 Rebuild the given mirror components forcibly.
 If autosynchronization was not turned off for the given device, this command
 should be unnecessary.
+.It Cm resize
+Change the size of the given mirror.
+.Pp
+Additional options include:
+.Bl -tag -width ".Fl s Ar size"
+.It Fl s Ar size
+New size of the mirror is expressed in logical block numbers.
+This option can be omitted, then it will be automatically calculated to
+maximum available size.
+.El
 .It Cm insert
 Add the given component(s) to the existing mirror.
 .Pp