nfsd: add an operation for unhashing a stateowner

Allow stateowners to be unhashed and destroyed when the last reference
is put. The unhashing must be idempotent. In a future patch, we'll add
some locking around it, but for now it's only protected by the
client_mutex.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 9cba295..2322460 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -335,6 +335,7 @@ struct nfs4_replay {
 struct nfs4_stateowner;
 
 struct nfs4_stateowner_operations {
+	void (*so_unhash)(struct nfs4_stateowner *);
 	void (*so_free)(struct nfs4_stateowner *);
 };