make_ext4fs: Modify ext4 filesystem setup to speed up fsck

1) Set EXT4_BG_INODE_UNINIT so fsck will skip scanning unused inodes
2) Use EXT4_FEATURE_RO_COMPAT_GDT_CSUM to enable group descriptor
checksums in filesystem which reduces overhead for fsck

BUG: 24747200
BUG: 28013112
Change-Id: I118ab26935442f452962b3a7c29c61acf76ad4d9
Signed-off-by: Mohamad Ayyash <[email protected]>

Author: mkayyash

ext4_utils/allocate.c

@@ -277,7 +277,7 @@ static void init_bg(struct block_group_info *bg, unsigned int i)
 	bg->free_blocks = info.blocks_per_group;
 	bg->free_inodes = info.inodes_per_group;
 	bg->first_free_inode = 1;
-	bg->flags = 0;
+	bg->flags = EXT4_BG_INODE_UNINIT;
 
 	bg->chunk_count = 0;
 	bg->max_chunk_count = 1;

ext4_utils/make_ext4fs.c

@@ -749,7 +749,8 @@ int make_ext4fs_internal(int fd, const char *_directory, const char *_target_out
 
 	info.feat_ro_compat |=
 			EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER |
-			EXT4_FEATURE_RO_COMPAT_LARGE_FILE;
+			EXT4_FEATURE_RO_COMPAT_LARGE_FILE |
+			EXT4_FEATURE_RO_COMPAT_GDT_CSUM;
 
 	info.feat_incompat |=
 			EXT4_FEATURE_INCOMPAT_EXTENTS |