9P: introduction of a new cache=mmap model.

 - Add cache=mmap option
 - Make mmap read-write while keeping it as synchronous as possible
 - Build writeback fid on mmap creation if it is writable

Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index a8e127c89627..099c7712631c 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -64,6 +64,7 @@ enum p9_session_flags {
 
 enum p9_cache_modes {
         CACHE_NONE,
+        CACHE_MMAP,
         CACHE_LOOSE,
         CACHE_FSCACHE,
 };