mke2fs: Add support for the undo I/O manager.
When running mke2fs, if a file system is detected
on the device, we use Undo I/O manager as the io manager.
This helps in reverting the changes made to the filesystem
in case we wrongly selected the device.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/misc/mke2fs.conf.5.in b/misc/mke2fs.conf.5.in
index 6734bf3..06592f2 100644
--- a/misc/mke2fs.conf.5.in
+++ b/misc/mke2fs.conf.5.in
@@ -107,6 +107,13 @@
to
.BR mke2fs (8).
.TP
+.I force_undo
+This relation, if set to a boolean value of true, forces
+.B mke2fs
+to always try to create an undo file, even if the undo file might be
+huge and it might extend the time to create the filesystem image
+because the inode table isn't being initialized lazily.
+.TP
.I fs_type
This relation specifies the default filesystem type if the user does not
specify it via the
@@ -140,6 +147,15 @@
specify one on the command line, and the filesystem-type
specific section of the configuration file does not specify a default
inode size.
+.TP
+.I undo_dir
+This relation specifies the directory where the undo file should be
+stored. It can be overriden via the
+.B E2FSPROGS_UNDO_DIR
+environemnt variable. If the directory location is set to the value
+.IR none ,
+.B mke2fs
+will not create an undo file.
.SH THE [fs_types] STANZA
Each tag in the
.I [fs_types]