From 27cf10e133c393f39399137b028c7b24d64ca06e Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Mon, 29 Apr 2013 16:21:15 -0700 Subject: [PATCH] Documentation: update nfs option in filesystem/vfat.txt Add descriptions about 'stale_rw' and 'nostale_ro' nfs options in filesystem/vfat.txt Signed-off-by: Namjae Jeon Signed-off-by: Ravishankar N Signed-off-by: Amit Sahrawat Acked-by: OGAWA Hirofumi Acked-by: Rob Landley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/vfat.txt | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt index d230dd9c99b0..4a93e98b290a 100644 --- a/Documentation/filesystems/vfat.txt +++ b/Documentation/filesystems/vfat.txt @@ -150,12 +150,28 @@ discard -- If set, issues discard/TRIM commands to the block device when blocks are freed. This is useful for SSD devices and sparse/thinly-provisoned LUNs. -nfs -- This option maintains an index (cache) of directory - inodes by i_logstart which is used by the nfs-related code to - improve look-ups. +nfs=stale_rw|nostale_ro + Enable this only if you want to export the FAT filesystem + over NFS. + + stale_rw: This option maintains an index (cache) of directory + inodes by i_logstart which is used by the nfs-related code to + improve look-ups. Full file operations (read/write) over NFS is + supported but with cache eviction at NFS server, this could + result in ESTALE issues. + + nostale_ro: This option bases the inode number and filehandle + on the on-disk location of a file in the MS-DOS directory entry. + This ensures that ESTALE will not be returned after a file is + evicted from the inode cache. However, it means that operations + such as rename, create and unlink could cause filehandles that + previously pointed at one file to point at a different file, + potentially causing data corruption. For this reason, this + option also mounts the filesystem readonly. + + To maintain backward compatibility, '-o nfs' is also accepted, + defaulting to stale_rw - Enable this only if you want to export the FAT filesystem - over NFS : 0,1,yes,no,true,false -- 2.34.1