cifs: update README to include details about 'fsc' option

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>

diff --git a/fs/cifs/README b/fs/cifs/README
index a7081ee..7099a52 100644 (file)
--- a/fs/cifs/README
+++ b/fs/cifs/README
@@ -301,6 +301,16 @@ A partial list of the supported mount options follows:
   gid          Set the default gid for inodes (similar to above).
   file_mode     If CIFS Unix extensions are not supported by the server
                this overrides the default mode for file inodes.
+  fsc          Enable local disk caching using FS-Cache (off by default). This
+               option could be useful to improve performance on a slow link,
+               heavily loaded server and/or network where reading from the
+               disk is faster than reading from the server (over the network).
+               This could also impact scalability positively as the
+               number of calls to the server are reduced. However, local
+               caching is not suitable for all workloads for e.g. read-once
+               type workloads. So, you need to consider carefully your
+               workload/scenario before using this option. Currently, local
+               disk caching is functional for CIFS files opened as read-only.
   dir_mode      If CIFS Unix extensions are not supported by the server 
                this overrides the default mode for directory inodes.
   port         attempt to contact the server on this tcp port, before