NFSv4: Fix up the exception handling. Ensure we always handle

   NFS4ERR_DELAY properly.
Signed-off-by: Trond Myklebust <trond.myklebust@fys.uio.no>

fs/nfs/nfs4state.c

@@ -416,6 +416,7 @@ __nfs4_put_open_state(struct nfs4_state *state)
 {
 	struct inode *inode = state->inode;
 	struct nfs4_state_owner *owner = state->owner;
+	struct nfs4_exception exception = { };
 	int status = 0;
 
 	if (!atomic_dec_and_lock(&state->count, &inode->i_lock)) {
@@ -427,15 +428,17 @@ __nfs4_put_open_state(struct nfs4_state *state)
 	spin_unlock(&inode->i_lock);
 	list_del(&state->open_states);
 	if (state->state != 0) {
-		do {
-			status = nfs4_do_close(inode, state);
+		for (;;) {
+			status = _nfs4_do_close(inode, state);
+			up(&owner->so_sema);
 			if (!status)
 				break;
-			up(&owner->so_sema);
-			status = nfs4_handle_error(NFS_SERVER(inode), status);
+			status = nfs4_handle_exception(NFS_SERVER(inode), status, &exception);
+			if (!exception.retry)
+				break;
 			down(&owner->so_sema);
-		} while (!status);
 		}
+	} else
 		up(&owner->so_sema);
 	nfs4_free_open_state(state);
 	nfs4_put_state_owner(owner);
@@ -453,6 +456,7 @@ nfs4_close_state(struct nfs4_state *state, mode_t mode)
 {
 	struct inode *inode = state->inode;
 	struct nfs4_state_owner *owner = state->owner;
+	struct nfs4_exception exception = { };
 	int newstate;
 	int status = 0;
 
@@ -477,17 +481,17 @@ nfs4_close_state(struct nfs4_state *state, mode_t mode)
 		if (state->state == newstate)
 			break;
 		if (newstate != 0)
-			status = nfs4_do_downgrade(inode, state, newstate);
+			status = _nfs4_do_downgrade(inode, state, newstate);
 		else
-			status = nfs4_do_close(inode, state);
+			status = _nfs4_do_close(inode, state);
 		if (!status) {
 			state->state = newstate;
 			break;
 		}
 		up(&owner->so_sema);
-		status = nfs4_handle_error(NFS_SERVER(inode), status);
+		status = nfs4_handle_exception(NFS_SERVER(inode), status, &exception);
 		down(&owner->so_sema);
-	} while (!status);
+	} while (exception.retry);
 	__nfs4_put_open_state(state);
 }
 

include/linux/nfs_fs.h

@@ -629,6 +629,11 @@ struct nfs4_state {
 };
 
 
+struct nfs4_exception {
+	long timeout;
+	int retry;
+};
+
 extern struct dentry_operations nfs4_dentry_operations;
 extern struct inode_operations nfs4_dir_inode_operations;
 
@@ -638,11 +643,12 @@ extern int nfs4_proc_setclientid_confirm(struct nfs4_client *);
 extern int nfs4_open_reclaim(struct nfs4_state_owner *, struct nfs4_state *);
 extern int nfs4_proc_async_renew(struct nfs4_client *);
 extern int nfs4_proc_renew(struct nfs4_client *);
-extern int nfs4_do_close(struct inode *, struct nfs4_state *);
-int nfs4_do_downgrade(struct inode *inode, struct nfs4_state *state, mode_t mode);
+extern int _nfs4_do_close(struct inode *, struct nfs4_state *);
+extern int _nfs4_do_downgrade(struct inode *inode, struct nfs4_state *state, mode_t mode);
 extern int nfs4_wait_clnt_recover(struct rpc_clnt *, struct nfs4_client *);
 extern struct inode *nfs4_atomic_open(struct inode *, struct dentry *, struct nameidata *);
 extern int nfs4_open_revalidate(struct inode *, struct dentry *, int);
+extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
 
 /* nfs4renewd.c */
 extern void nfs4_schedule_state_renewal(struct nfs4_client *);
@@ -663,7 +669,6 @@ extern void nfs4_put_open_state(struct nfs4_state *);
 extern void nfs4_close_state(struct nfs4_state *, mode_t);
 extern struct nfs4_state *nfs4_find_state(struct inode *, struct rpc_cred *, mode_t mode);
 extern void nfs4_increment_seqid(int status, struct nfs4_state_owner *sp);
-extern int nfs4_handle_error(struct nfs_server *, int);
 extern void nfs4_schedule_state_recovery(struct nfs4_client *);
 extern struct nfs4_lock_state *nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t);
 extern struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t);