From 2bcf002159c2aedd5c0ab5a21c3ea73fec87ff8d Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Thu, 10 Mar 2011 16:26:32 +0200 Subject: [PATCH] UBIFS: do not check data crc by default Change the default UBIFS behavior WRT data CRC checking. Currently, UBIFS checks data CRC when reading, which slows it down quite a bit, and this is the default option. However, it looks like in average user does not need this feature and would prefer faster read speed over extra reliability. And this seems to be de-facto standard that file-systems do not check data CRC every time they read from the media. Thus, make UBIFS default behavior so that it does not check data CRC. This corresponds to the no_chk_data_crc mount option. Those users who need extra protection can always enable it using the chk_data_crc option. Please, read more information about this feature here: http://www.linux-mtd.infradead.org/doc/ubifs.html#L_checksumming Signed-off-by: Artem Bityutskiy --- Documentation/filesystems/ubifs.txt | 4 ++-- fs/ubifs/super.c | 1 + 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt index 12fedb7834c6..d7b13b01e980 100644 --- a/Documentation/filesystems/ubifs.txt +++ b/Documentation/filesystems/ubifs.txt @@ -82,12 +82,12 @@ Mount options bulk_read read more in one go to take advantage of flash media that read faster sequentially no_bulk_read (*) do not bulk-read -no_chk_data_crc skip checking of CRCs on data nodes in order to +no_chk_data_crc (*) skip checking of CRCs on data nodes in order to improve read performance. Use this option only if the flash media is highly reliable. The effect of this option is that corruption of the contents of a file can go unnoticed. -chk_data_crc (*) do not skip checking CRCs on data nodes +chk_data_crc do not skip checking CRCs on data nodes compr=none override default compressor and set it to "none" compr=lzo override default compressor and set it to "lzo" compr=zlib override default compressor and set it to "zlib" diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c index e9585ad90f5e..1da5155a1bea 100644 --- a/fs/ubifs/super.c +++ b/fs/ubifs/super.c @@ -1977,6 +1977,7 @@ static int ubifs_fill_super(struct super_block *sb, void *data, int silent) INIT_LIST_HEAD(&c->old_buds); INIT_LIST_HEAD(&c->orph_list); INIT_LIST_HEAD(&c->orph_new); + c->no_chk_data_crc = 1; c->vfs_sb = sb; c->highest_inum = UBIFS_FIRST_INO;