If during formatting we'd lose more than half of a block group to group descriptors and other metadata, enable the meta_bg feature. This enables us to create >500T filesystems with default options. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- lib/ext2fs/initialize.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c index f672a27..b5ca928 100644 --- a/lib/ext2fs/initialize.c +++ b/lib/ext2fs/initialize.c @@ -381,6 +381,11 @@ ipg_retry: overhead = (int) (3 + fs->inode_blocks_per_group + super->s_reserved_gdt_blocks); + /* Enable meta_bg if we'd lose more than 3/4 of a BG to GDT blocks. */ + if (super->s_reserved_gdt_blocks + fs->desc_blocks > + super->s_blocks_per_group * 3 / 4) + fs->super->s_feature_incompat |= EXT2_FEATURE_INCOMPAT_META_BG; + if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) overhead++; else -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
