9p: Add fscache support to 9p

This patch adds a persistent, read-only caching facility for
9p clients using the FS-Cache caching backend.

When the fscache facility is enabled, each inode is associated
with a corresponding vcookie which is an index into the FS-Cache
indexing tree. The FS-Cache indexing tree is indexed at 3 levels:
- session object associated with each mount.
- inode/vcookie
- actual data (pages)

A cache tag is chosen randomly for each session. These tags can
be read off /sys/fs/9p/caches and can be passed as a mount-time
parameter to re-attach to the specified caching session.

Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/9p/Makefile b/fs/9p/Makefile
index bc7f0d1551e6..1a940ec7af61 100644
--- a/fs/9p/Makefile
+++ b/fs/9p/Makefile
@@ -8,5 +8,6 @@ obj-$(CONFIG_9P_FS) := 9p.o
         vfs_dir.o \
         vfs_dentry.o \
         v9fs.o \
-        fid.o \
+        fid.o
 
+9p-$(CONFIG_9P_FSCACHE) += cache.o