[PATCH] ext3: external journal device as a mount option

The patch below adds a new mount option to allow the external journal
device to be specified.

The syntax is as follows:
# mount -t ext3 -o journal_dev=0x0820 ...
where 0x0820 means major=8 and minor=32.

Signed-off-by: Johann Lombardi <johann.lombardi@bull.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt
index 9840d5b8d5b9..22e4040564d5 100644
--- a/Documentation/filesystems/ext3.txt
+++ b/Documentation/filesystems/ext3.txt
@@ -22,6 +22,11 @@ journal=inum		When a journal already exists, this option is
                         the inode which will represent the ext3 file
                         system's journal file.
 
+journal_dev=devnum      When the external journal device's major/minor numbers
+                        have changed, this option allows to specify the new
+                        journal location. The journal device is identified
+                        through its new major/minor numbers encoded in devnum.
+
 noload                  Don't load the journal on mounting.
 
 data=journal            All data are committed into the journal prior