| From 4198ce4de86d2144ce127bba0d263a005926acf2 Mon Sep 17 00:00:00 2001 |
| From: "Darrick J. Wong" <darrick.wong@oracle.com> |
| Date: Sat, 24 Oct 2015 00:30:02 -0400 |
| Subject: [PATCH 03/16] libext2fs: automatically enable meta_bg to avoid |
| filling up BG 0 |
| |
| commit 03940aac5492879ef365b07e69105a98f4dbabf9 |
| |
| If during formatting we'd lose more than 75% 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@oracle.com> |
| Signed-off-by: Theodore Ts'o <tytso@mit.edu> |
| |
| lib/ext2fs/initialize.c | 5 +++++ |
| 1 file changed, 5 insertions(+) |
| |
| diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c |
| index 3548c56c..0b8355d8 100644 |
| |
| |
| @@ -379,6 +379,11 @@ 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 |
| -- |
| 2.20.1 |
| |