[PATCH] nfsd: add a spinlock to nfs4_stid

[Jeff Layton <jlayton@poochiereds.net>]

...to allow seqid morphing to be serialized wrt to its copying.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
---
 fs/nfsd/nfs4state.c |  1 +
 fs/nfsd/state.h     | 13 +++++++------
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index bec2cc7eac78..156fc9183728 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -577,6 +577,7 @@ struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl,
 	stid->sc_stateid.si_opaque.so_clid = cl->cl_clientid;
 	/* Will be incremented before return to client: */
 	atomic_set(&stid->sc_count, 1);
+	spin_lock_init(&stid->sc_lock);
 
 	/*
 	 * It shouldn't be a problem to reuse an opaque stateid value.
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 6f35fec88517..e3a191ea771c 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -84,7 +84,7 @@ struct nfsd4_callback_ops {
  * fields that are of general use to any stateid.
  */
 struct nfs4_stid {
-	atomic_t sc_count;
+	atomic_t		sc_count;
 #define NFS4_OPEN_STID 1
 #define NFS4_LOCK_STID 2
 #define NFS4_DELEG_STID 4
@@ -94,11 +94,12 @@ struct nfs4_stid {
 #define NFS4_REVOKED_DELEG_STID 16
 #define NFS4_CLOSED_DELEG_STID 32
 #define NFS4_LAYOUT_STID 64
-	unsigned char sc_type;
-	stateid_t sc_stateid;
-	struct nfs4_client *sc_client;
-	struct nfs4_file *sc_file;
-	void (*sc_free)(struct nfs4_stid *);
+	unsigned char		sc_type;
+	stateid_t		sc_stateid;
+	spinlock_t		sc_lock;
+	struct nfs4_client	*sc_client;
+	struct nfs4_file	*sc_file;
+	void			(*sc_free)(struct nfs4_stid *);
 };
 
 /*
-- 
2.4.3