Add support for the test_fs flag

The test_fs flag is an "ok to be used with test kernel code" flag.  It
makes it easier for us to determine whether a filesystem should be
mounted using ext4 or not.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

4 files changed, 93 insertions, 6 deletions

diff --git a/misc/mke2fs.8.in b/misc/mke2fs.8.in
index a3dc4a1c..9afd7f43 100644
--- a/misc/mke2fs.8.in
+++ b/misc/mke2fs.8.in
@@ -187,6 +187,10 @@ filesystem blocks per stripe.
 .BI resize= max-online-resize
 Reserve enough space so that the block group descriptor table can grow
 to support a filesystem that has max-online-resize blocks.
+.TP
+.B test_fs
+Set a flag in the filesystem superblock indicating that it may be
+mounted using experimental kernel code, such as the ext4dev filesystem.
 .RE
 .TP
 .BI \-f " fragment-size"
diff --git a/misc/mke2fs.c b/misc/mke2fs.c
index 7a360eab..e754d6b4 100644
--- a/misc/mke2fs.c
+++ b/misc/mke2fs.c
@@ -849,6 +849,8 @@ static void parse_extended_opts(struct ext2_super_block *param,
 
 				param->s_reserved_gdt_blocks = rsv_gdb;
 			}
+		} else if (!strcmp(token, "test_fs")) {
+			param->s_flags |= EXT2_FLAGS_TEST_FILESYS;
 		} else
 			r_usage++;
 	}
@@ -859,7 +861,8 @@ static void parse_extended_opts(struct ext2_super_block *param,
 			"\tis set off by an equals ('=') sign.\n\n"
 			"Valid extended options are:\n"
 			"\tstride=<stride length in blocks>\n"
-			"\tresize=<resize maximum size in blocks>\n\n"));
+			"\tresize=<resize maximum size in blocks>\n"
+			"\ttest_fs\n"));
 		free(buf);
 		exit(1);
 	}
@@ -1556,6 +1559,9 @@ int main (int argc, char *argv[])
 		exit(1);
 	}
 
+	if (fs_param.s_flags & EXT2_FLAGS_TEST_FILESYS)
+		fs->super->s_flags |= EXT2_FLAGS_TEST_FILESYS;
+
 	/*
 	 * Wipe out the old on-disk superblock
 	 */
diff --git a/misc/tune2fs.8.in b/misc/tune2fs.8.in
index 2e617db8..d1edbd99 100644
--- a/misc/tune2fs.8.in
+++ b/misc/tune2fs.8.in
@@ -61,6 +61,10 @@ tune2fs \- adjust tunable filesystem parameters on ext2/ext3 filesystems
 .I mount-count
 ]
 [
+.B \-E
+.I extended-options
+]
+[
 .B \-L
 .I volume-name
 ]
@@ -144,6 +148,21 @@ Remount filesystem read-only.
 Cause a kernel panic.
 .RE
 .TP
+.BI \-E " extended-options"
+Set extended options for the filesystem.  Extended options are comma
+separated, and may take an argument using the equals ('=') sign.  The 
+following extended options are supported:
+.RS 1.2i
+.TP
+.B test_fs
+Set a flag in the filesystem superblock indicating that it may be
+mounted using experimental kernel code, such as the ext4dev filesystem.
+.TP
+.B ^test_fs
+Clear the test_fs flag, indicating the filesystem should only be mounted
+using production-level filesystem code.
+.RE
+.TP
 .B \-f
 Force the tune2fs operation to complete even in the face of errors.  This 
 option is useful when removing the 
diff --git a/misc/tune2fs.c b/misc/tune2fs.c
index 833b9943..fce27e2c 100644
--- a/misc/tune2fs.c
+++ b/misc/tune2fs.c
@@ -71,6 +71,7 @@ static unsigned short errors;
 static int open_flag;
 static char *features_cmd;
 static char *mntopts_cmd;
+static char *extended_cmd;
 
 int journal_size, journal_flags;
 char *journal_device;
@@ -87,10 +88,10 @@ static void usage(void)
 		  "\t[-i interval[d|m|w]] [-j] [-J journal_options]\n"
 		  "\t[-l] [-s sparse_flag] [-m reserved_blocks_percent]\n"
 		  "\t[-o [^]mount_options[,...]] [-r reserved_blocks_count]\n"
-		  "\t[-u user] [-C mount_count] [-L volume_label] "
-		  "[-M last_mounted_dir]\n"
-		  "\t[-O [^]feature[,...]] [-T last_check_time] [-U UUID]"
-		  " device\n"), program_name);
+		  "\t[-u user] [-C mount_count] [-L volume_label]\n"
+		  "\t[-M last_mounted_dir] [-O [^]feature[,...]]\n"
+		  "\t[-E extended-option[,...]] [-T last_check_time] "
+		  "[-U UUID] device\n"), program_name);
 	exit (1);
 }
 
@@ -505,7 +506,7 @@ static void parse_tune2fs_options(int argc, char **argv)
 	struct passwd * pw;
 
 	printf("tune2fs %s (%s)\n", E2FSPROGS_VERSION, E2FSPROGS_DATE);
-	while ((c = getopt(argc, argv, "c:e:fg:i:jlm:o:r:s:u:C:J:L:M:O:T:U:")) != EOF)
+	while ((c = getopt(argc, argv, "c:e:fg:i:jlm:o:r:s:u:C:E:J:L:M:O:T:U:")) != EOF)
 		switch (c)
 		{
 			case 'c':
@@ -548,6 +549,10 @@ static void parse_tune2fs_options(int argc, char **argv)
 				e_flag = 1;
 				open_flag = EXT2_FLAG_RW;
 				break;
+			case 'E':
+				extended_cmd = optarg;
+				open_flag = EXT2_FLAG_RW;
+				break;
 			case 'f': /* Force */
 				f_flag = 1;
 				break;
@@ -739,6 +744,57 @@ void do_findfs(int argc, char **argv)
 	exit(0);
 }
 
+static void parse_extended_opts(ext2_filsys fs, const char *opts)
+{
+	char	*buf, *token, *next, *p, *arg;
+	int	len;
+	int	r_usage = 0;
+
+	len = strlen(opts);
+	buf = malloc(len+1);
+	if (!buf) {
+		fprintf(stderr,
+			_("Couldn't allocate memory to parse options!\n"));
+		exit(1);
+	}
+	strcpy(buf, opts);
+	for (token = buf; token && *token; token = next) {
+		p = strchr(token, ',');
+		next = 0;
+		if (p) {
+			*p = 0;
+			next = p+1;
+		}
+		arg = strchr(token, '=');
+		if (arg) {
+			*arg = 0;
+			arg++;
+		}
+		if (!strcmp(token, "test_fs")) {
+			fs->super->s_flags |= EXT2_FLAGS_TEST_FILESYS;
+			printf("Setting test filesystem flag\n");
+			ext2fs_mark_super_dirty(fs);
+		} else if (!strcmp(token, "^test_fs")) {
+			fs->super->s_flags &= ~EXT2_FLAGS_TEST_FILESYS;
+			printf("Clearing test filesystem flag\n");
+			ext2fs_mark_super_dirty(fs);
+		} else
+			r_usage++;
+	}
+	if (r_usage) {
+		fprintf(stderr, _("\nBad options specified.\n\n"
+			"Extended options are separated by commas, "
+			"and may take an argument which\n"
+			"\tis set off by an equals ('=') sign.\n\n"
+			"Valid extended options are:\n"
+			"\ttest_fs\n"
+			"\t^test_fs\n"));
+		free(buf);
+		exit(1);
+	}
+	free(buf);
+}	
+
 
 int main (int argc, char ** argv)
 {
@@ -902,6 +958,8 @@ int main (int argc, char ** argv)
 		update_mntopts(fs, mntopts_cmd);
 	if (features_cmd)
 		update_feature_set(fs, features_cmd);
+	if (extended_cmd)
+		parse_extended_opts(fs, extended_cmd);
 	if (journal_size || journal_device)
 		add_journal(fs);