qubes-linux-kernel/patches.suse/reiserfs-barrier-default
2011-04-19 22:09:59 +02:00

57 lines
2.1 KiB
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From: Jeff Mahoney <jeffm@suse.com>
Subject: Make reiserfs default to barrier=flush
Patch-mainline: not yet
Change the default reiserfs mount option to barrier=flush
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
fs/reiserfs/Kconfig | 22 ++++++++++++++++++++++
fs/reiserfs/super.c | 3 +++
2 files changed, 25 insertions(+)
--- a/fs/reiserfs/Kconfig
+++ b/fs/reiserfs/Kconfig
@@ -50,6 +50,28 @@ config REISERFS_PROC_INFO
Almost everyone but ReiserFS developers and people fine-tuning
reiserfs or tracing problems should say N.
+config REISERFS_DEFAULTS_TO_BARRIERS_ENABLED
+ bool "Default to 'barrier=flush' in reiserfs"
+ depends on REISERFS_FS
+ help
+ Modern disk drives support write caches that can speed up writeback.
+ Some devices, in order to improve their performance statistics,
+ report that the write has been completed even when it has only
+ been committed to volatile cache memory. This can result in
+ severe corruption in the event of power loss.
+
+ The -o barrier option enables the file system to direct the block
+ layer to issue a barrier, which ensures that the cache has been
+ flushed before proceeding. This can produce some slowdown in
+ certain environments, but allows higher end storage arrays with
+ battery-backed caches to report completes writes sooner than
+ would be otherwise possible.
+
+ Without this option, disk write caches should be disabled if
+ you value data integrity over writeback performance.
+
+ If unsure, say N.
+
config REISERFS_FS_XATTR
bool "ReiserFS extended attributes"
depends on REISERFS_FS
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -1637,6 +1637,9 @@ static int reiserfs_fill_super(struct su
/* Set default values for options: non-aggressive tails, RO on errors */
REISERFS_SB(s)->s_mount_opt |= (1 << REISERFS_SMALLTAIL);
REISERFS_SB(s)->s_mount_opt |= (1 << REISERFS_ERROR_RO);
+#ifdef CONFIG_REISERFS_DEFAULTS_TO_BARRIERS_ENABLED
+ REISERFS_SB(s)->s_mount_opt |= (1 << REISERFS_BARRIER_FLUSH);
+#endif
/* no preallocation minimum, be smart in
reiserfs_file_write instead */
REISERFS_SB(s)->s_alloc_options.preallocmin = 0;