[PATCH-e2fsprogs] Allow tune2fs -I if only one group per flex

[Peng Tao <bergwolf@gmail.com>]

This can be caused by tune2fs -O flex_bg.
And tune2fs -I should work okay for such partitions.

Signed-off-by: Peng Tao <bergwolf@gmail.com>
---
 misc/tune2fs.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/misc/tune2fs.c b/misc/tune2fs.c
index 887a702..ee982e5 100644
--- a/misc/tune2fs.c
+++ b/misc/tune2fs.c
@@ -1715,7 +1715,8 @@ retry_open:
 			exit(1);
 		}
 		if (fs->super->s_feature_incompat &
-		    EXT4_FEATURE_INCOMPAT_FLEX_BG) {
+		    EXT4_FEATURE_INCOMPAT_FLEX_BG &&
+		    fs->super->s_log_groups_per_flex) {
 			fputs(_("Changing the inode size not supported for "
 				"filesystems with the flex_bg\n"
 				"feature enabled.\n"),
-- 
1.6.1.3