From ba9e0afc5ab0d0ff26880e37ac71c281b644ce00 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Thu, 16 Feb 2012 23:16:34 -0500 Subject: [PATCH] mke2fs: allow file systems w/ uninit_bg to be recovered with mke2fs -S The command mke2fs -S is used as a last ditch recovery command to write new superblock and block group descriptors, but _not_ to destroy the inode table in hopes of recovering from a badly corrupted file system. If the uninit_bg feature is enabled, we need to make sure to clear the unused inodes count field in the block group descriptors or else e2fsck -fy will leave the file system completely empty. Thanks to Akira Fujita for reporting this problem. Signed-off-by: "Theodore Ts'o" --- misc/mke2fs.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/misc/mke2fs.c b/misc/mke2fs.c index 08789c4..c70c1b4 100644 --- a/misc/mke2fs.c +++ b/misc/mke2fs.c @@ -2434,6 +2434,17 @@ int main (int argc, char *argv[]) if (super_only) { fs->super->s_state |= EXT2_ERROR_FS; fs->flags &= ~(EXT2_FLAG_IB_DIRTY|EXT2_FLAG_BB_DIRTY); + /* + * The command "mke2fs -S" is used to recover + * corrupted file systems, so do not mark any of the + * inodes as unused; we want e2fsck to consider all + * inodes as potentially containing recoverable data. + */ + if (fs->super->s_feature_ro_compat & + EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { + for (i = 1; i < fs->group_desc_count; i++) + ext2fs_bg_itable_unused_set(fs, i, 0); + } } else { /* rsv must be a power of two (64kB is MD RAID sb alignment) */ blk64_t rsv = 65536 / fs->blocksize; -- 1.8.3.1