commit 60e7c2bfcb23ddfcf2f63d8d8a700e871071a574
Author: Andrew Price <anprice@redhat.com>
Date:   Thu Jul 14 13:20:39 2022 +0100

    mkfs.gfs2: Add -U UUID option
    
    Allow the user to specify the filesystem UUID, similar to mkfs.ext4's -U
    option.
    
    Resolves: rhbz#2180782
    
    Signed-off-by: Andrew Price <anprice@redhat.com>

diff --git a/gfs2/man/mkfs.gfs2.8 b/gfs2/man/mkfs.gfs2.8
index 35e355a5..f4fd33f3 100644
--- a/gfs2/man/mkfs.gfs2.8
+++ b/gfs2/man/mkfs.gfs2.8
@@ -120,6 +120,12 @@ unique file system name used to distinguish this gfs2 file system.  Valid
 \fIclustername\fRs and \fIlockspace\fRs may only contain alphanumeric
 characters, hyphens (-) and underscores (_).
 .TP
+\fB-U\fP \fIUUID\fR
+Specify the filesystem UUID. The argument must be string of hexadecimal digits
+separated by hyphens, of the form "1b4e28ba-2fa1-11d2-883f-b9a761bde3fb". If
+this option is omitted, the filesystem's UUID is randomly generated. Note that
+no attempt is made to prevent UUID clashes between filesystems.
+.TP
 \fB-V\fP
 Print program version information, then exit.
 .TP
diff --git a/gfs2/mkfs/main_mkfs.c b/gfs2/mkfs/main_mkfs.c
index 09e756fb..c661abae 100644
--- a/gfs2/mkfs/main_mkfs.c
+++ b/gfs2/mkfs/main_mkfs.c
@@ -55,6 +55,7 @@ static void print_usage(const char *prog_name)
 	    "-q", NULL,          _("Don't print anything"),
 	    "-r", _("<size>"),   _("Size of resource groups, in megabytes"),
 	    "-t", _("<name>"),   _("Name of the lock table"),
+	    "-U", _("<UUID>"),   _("The UUID of the file system"),
 	    "-V", NULL,          _("Display program version information, then exit"),
 	    NULL, NULL, NULL /* Must be kept at the end */
 	};
@@ -122,6 +123,7 @@ struct mkfs_opts {
 	uint32_t journals;
 	const char *lockproto;
 	const char *locktable;
+	const char *uuid;
 	struct mkfs_dev dev;
 	unsigned discard:1;
 
@@ -137,6 +139,7 @@ struct mkfs_opts {
 	unsigned got_locktable:1;
 	unsigned got_device:1;
 	unsigned got_topol:1;
+	unsigned got_uuid:1;
 
 	unsigned override:1;
 	unsigned quiet:1;
@@ -321,7 +324,7 @@ static void opts_get(int argc, char *argv[], struct mkfs_opts *opts)
 {
 	int c;
 	while (1) {
-		c = getopt(argc, argv, "-b:c:DhJ:j:KOo:p:qr:t:V");
+		c = getopt(argc, argv, "-b:c:DhJ:j:KOo:p:qr:t:U:V");
 		if (c == -1)
 			break;
 
@@ -373,6 +376,10 @@ static void opts_get(int argc, char *argv[], struct mkfs_opts *opts)
 		case 'o':
 			opt_parse_extended(optarg, opts);
 			break;
+		case 'U':
+			opts->uuid = optarg;
+			opts->got_uuid = 1;
+			break;
 		case 'V':
 			printf("mkfs.gfs2 %s (built %s %s)\n", VERSION,
 			       __DATE__, __TIME__);
@@ -1030,6 +1037,28 @@ static void open_dev(struct mkfs_dev *dev, int withprobe)
 		exit(1);
 }
 
+static void sb_init(struct gfs2_sb *sb, unsigned bsize, struct mkfs_opts *opts)
+{
+	memset(sb, 0, sizeof(struct gfs2_sb));
+	sb->sb_header.mh_magic = GFS2_MAGIC;
+	sb->sb_header.mh_type = GFS2_METATYPE_SB;
+	sb->sb_header.mh_format = GFS2_FORMAT_SB;
+	sb->sb_fs_format = GFS2_FORMAT_FS;
+	sb->sb_multihost_format = GFS2_FORMAT_MULTI;
+	sb->sb_bsize = bsize;
+	sb->sb_bsize_shift = ffs(bsize) - 1;
+#ifdef GFS2_HAS_UUID
+	if (opts->got_uuid) {
+		int err = uuid_parse(opts->uuid, sb->sb_uuid);
+		if (err != 0) {
+			fprintf(stderr, _("Failed to parse UUID option."));
+			exit(1);
+		}
+	} else
+		uuid_generate(sb->sb_uuid);
+#endif
+}
+
 int main(int argc, char *argv[])
 {
 	struct gfs2_sbd sbd;
@@ -1056,7 +1085,7 @@ int main(int argc, char *argv[])
 	}
 
 	sbd_init(&sbd, &opts, bsize);
-	lgfs2_sb_init(&sb, bsize);
+	sb_init(&sb, bsize, &opts);
 	if (opts.debug) {
 		printf(_("File system options:\n"));
 		printf("  bsize = %u\n", sbd.bsize);
diff --git a/tests/mkfs.at b/tests/mkfs.at
index e7ce8e80..95e1aed2 100644
--- a/tests/mkfs.at
+++ b/tests/mkfs.at
@@ -171,3 +171,13 @@ GFS_TGT_SIZE(64M)
 AT_CHECK([$GFS_MKFS -p lock_nolock -j2 $GFS_TGT], 0, [ignore], [ignore])
 AT_CHECK([fsck.gfs2 -n $GFS_TGT], 0, [ignore], [ignore])
 AT_CLEANUP
+
+AT_SETUP([UUID option])
+AT_KEYWORDS(mkfs.gfs2 mkfs)
+GFS_TGT_REGEN
+AT_CHECK([$GFS_MKFS -p lock_nolock $GFS_TGT -U], 1, [ignore], [ignore])
+AT_CHECK([$GFS_MKFS -p lock_nolock -U 42 $GFS_TGT], 1, [ignore], [ignore])
+AT_CHECK([$GFS_MKFS -p lock_nolock -U 1b4e28ba-2fa1-11d2-883f-b9a761bde3fb4 $GFS_TGT], 1, [ignore], [ignore])
+AT_CHECK([$GFS_MKFS -p lock_nolock -U 1b4e28ba-2fa1-11d2-883f-b9a761bde3f $GFS_TGT], 1, [ignore], [ignore])
+GFS_FSCK_CHECK([$GFS_MKFS -p lock_nolock -U 1b4e28ba-2fa1-11d2-883f-b9a761bde3fb $GFS_TGT])
+AT_CLEANUP