[PATCH] ext3: Add "-o bh" option
This patch adds "-o bh" option to force use of buffer_heads. This option
is needed when we make "nobh" as default - and if we run into problems.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt
index afb1335..4aecc9b 100644
--- a/Documentation/filesystems/ext3.txt
+++ b/Documentation/filesystems/ext3.txt
@@ -113,6 +113,14 @@
grpquota
usrquota
+bh (*) ext3 associates buffer heads to data pages to
+nobh (a) cache disk block mapping information
+ (b) link pages into transaction to provide
+ ordering guarantees.
+ "bh" option forces use of buffer heads.
+ "nobh" option tries to avoid associating buffer
+ heads (supported only for "writeback" mode).
+
Specification
=============
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index b2891cc..b748336 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -630,7 +630,7 @@
Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
- Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh,
+ Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
@@ -666,6 +666,7 @@
{Opt_noreservation, "noreservation"},
{Opt_noload, "noload"},
{Opt_nobh, "nobh"},
+ {Opt_bh, "bh"},
{Opt_commit, "commit=%u"},
{Opt_journal_update, "journal=update"},
{Opt_journal_inum, "journal=%u"},
@@ -1014,6 +1015,9 @@
case Opt_nobh:
set_opt(sbi->s_mount_opt, NOBH);
break;
+ case Opt_bh:
+ clear_opt(sbi->s_mount_opt, NOBH);
+ break;
default:
printk (KERN_ERR
"EXT3-fs: Unrecognized mount option \"%s\" "