From 146bca72c7e6ba52de82a63b1fce7934dc103dbc Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 16 Mar 2009 18:27:37 +0100 Subject: udf: Don't write integrity descriptor too often We update information in logical volume integrity descriptor after each allocation (as LVID contains free space, number of directories and files on disk etc.). If the filesystem is on some phase change media, this leads to its quick degradation as such media is able to handle only 10000 overwrites or so. We solve the problem by writing new information into LVID only on umount, remount-ro and sync. This solves the problem at the price of longer media inconsistency (previously media became consistent after pdflush flushed dirty LVID buffer) but that should be acceptable. Report by and patch written in cooperation with Rich Coe . Signed-off-by: Jan Kara --- fs/udf/udf_sb.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/udf/udf_sb.h') diff --git a/fs/udf/udf_sb.h b/fs/udf/udf_sb.h index 46fea3ea70a9..d113b72c2768 100644 --- a/fs/udf/udf_sb.h +++ b/fs/udf/udf_sb.h @@ -148,6 +148,8 @@ struct udf_sb_info { struct inode *s_vat_inode; struct mutex s_alloc_mutex; + /* Protected by s_alloc_mutex */ + unsigned int s_lvid_dirty; }; static inline struct udf_sb_info *UDF_SB(struct super_block *sb) -- cgit v1.2.3