Revert "mke2fs: prevent creation of unmountable ext4 with large flex_bg count"
This reverts commit d988201ef9cb6f7b521e544061976ab4270a3f89.
The problem with this commit is that causes common small file system
configurations to fail. For example:
mke2fs -O flex_bg -b 4096 -I 1024 -F /tmp/tt 79106
mke2fs 1.42.11 (09-Jul-2014)
/tmp/tt: Invalid argument passed to ext2 library while setting
up superblock
This check in ext2fs_initialize() was added to prevent the metadata
from being allocated beyond the end of the filesystem, but it is
also causing a wide range of failures for small filesystems.
We'll address this in a different way, by using a smarter algorithm
for deciding the layout of metadata blocks for the last flex block
group.
Reported-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c
index de358fd..36c94a9 100644
--- a/lib/ext2fs/initialize.c
+++ b/lib/ext2fs/initialize.c
@@ -91,10 +91,8 @@
unsigned int rem;
unsigned int overhead = 0;
unsigned int ipg;
- unsigned int flexbg_size;
dgrp_t i;
blk64_t free_blocks;
- blk64_t flexbg_overhead;
blk_t numblocks;
int rsv_gdt;
int csum_flag;
@@ -421,28 +419,6 @@
}
/*
- * Calculate the flex_bg related metadata blocks count.
- * It includes the boot block, the super block,
- * the block group descriptors, the reserved gdt blocks,
- * the block bitmaps, the inode bitmaps and the inode tables.
- * This is a simple check, so that the backup superblock and
- * other feature related blocks are not considered.
- */
- flexbg_size = 1 << fs->super->s_log_groups_per_flex;
- flexbg_overhead = super->s_first_data_block + 1 +
- fs->desc_blocks + super->s_reserved_gdt_blocks +
- (__u64)flexbg_size * (2 + fs->inode_blocks_per_group);
-
- /*
- * Disallow creating ext4 which breaks flex_bg metadata layout
- * obviously.
- */
- if (flexbg_overhead > ext2fs_blocks_count(fs->super)) {
- retval = EXT2_ET_INVALID_ARGUMENT;
- goto cleanup;
- }
-
- /*
* At this point we know how big the filesystem will be. So
* we can do any and all allocations that depend on the block
* count.