SUNRPC: pipefs per-net operations helper introduced

During per-net pipes creation and destruction we have to make sure, that pipefs
sb exists for the whole creation/destruction cycle. This is done by using
special mutex which controls pipefs sb reference on network namespace context.
Helper consists of two parts: first of them (rpc_get_dentry_net) searches for
dentry with specified name and returns with mutex taken on success. When pipe
creation or destructions is completed, caller should release this mutex by
rpc_put_dentry_net call.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/sunrpc/rpc_pipe_fs.h b/include/linux/sunrpc/rpc_pipe_fs.h
index 2f3382230141..c13fca34dc9c 100644
--- a/include/linux/sunrpc/rpc_pipe_fs.h
+++ b/include/linux/sunrpc/rpc_pipe_fs.h
@@ -53,6 +53,9 @@ enum {
 
 extern struct dentry *rpc_d_lookup_sb(const struct super_block *sb,
                                       const unsigned char *dir_name);
+extern void rpc_pipefs_init_net(struct net *net);
+extern struct super_block *rpc_get_sb_net(const struct net *net);
+extern void rpc_put_sb_net(const struct net *net);
 
 extern ssize_t rpc_pipe_generic_upcall(struct file *, struct rpc_pipe_msg *,
                                        char __user *, size_t);