NFS client bugfixes for Linux 4.10

Stable patches:
 - NFSv4.1: Fix a deadlock in layoutget
 - NFSv4 must not bump sequence ids on NFS4ERR_MOVED errors
 - NFSv4 Fix a regression with OPEN EXCLUSIVE4 mode
 - Fix a memory leak when removing the SUNRPC module
 
 Bugfixes:
 - Fix a reference leak in _pnfs_return_layout
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Merge tag 'nfs-for-4.10-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Stable patches:
   - NFSv4.1: Fix a deadlock in layoutget
   - NFSv4 must not bump sequence ids on NFS4ERR_MOVED errors
   - NFSv4 Fix a regression with OPEN EXCLUSIVE4 mode
   - Fix a memory leak when removing the SUNRPC module

  Bugfixes:
   - Fix a reference leak in _pnfs_return_layout"

* tag 'nfs-for-4.10-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  pNFS: Fix a reference leak in _pnfs_return_layout
  nfs: Fix "Don't increment lock sequence ID after NFS4ERR_MOVED"
  SUNRPC: cleanup ida information when removing sunrpc module
  NFSv4.0: always send mode in SETATTR after EXCLUSIVE4
  nfs: Don't increment lock sequence ID after NFS4ERR_MOVED
  NFSv4.1: Fix a deadlock in layoutget

fs/nfs/nfs4proc.c

@@ -2700,7 +2700,8 @@ static inline void nfs4_exclusive_attrset(struct nfs4_opendata *opendata,
 		sattr->ia_valid |= ATTR_MTIME;
 
 	/* Except MODE, it seems harmless of setting twice. */
-	if ((attrset[1] & FATTR4_WORD1_MODE))
+	if (opendata->o_arg.createmode != NFS4_CREATE_EXCLUSIVE &&
+		attrset[1] & FATTR4_WORD1_MODE)
 		sattr->ia_valid &= ~ATTR_MODE;
 
 	if (attrset[2] & FATTR4_WORD2_SECURITY_LABEL)
@@ -8490,6 +8491,7 @@ nfs4_layoutget_handle_exception(struct rpc_task *task,
 		goto out;
 	}
 
+	nfs4_sequence_free_slot(&lgp->res.seq_res);
 	err = nfs4_handle_exception(server, nfs4err, exception);
 	if (!status) {
 		if (exception->retry)

fs/nfs/nfs4state.c

@@ -1091,6 +1091,7 @@ static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 		case -NFS4ERR_BADXDR:
 		case -NFS4ERR_RESOURCE:
 		case -NFS4ERR_NOFILEHANDLE:
+		case -NFS4ERR_MOVED:
 			/* Non-seqid mutating errors */
 			return;
 	};

fs/nfs/pnfs.c

@@ -1200,10 +1200,10 @@ _pnfs_return_layout(struct inode *ino)
 
 	send = pnfs_prepare_layoutreturn(lo, &stateid, NULL);
 	spin_unlock(&ino->i_lock);
-	pnfs_free_lseg_list(&tmp_list);
 	if (send)
 		status = pnfs_send_layoutreturn(lo, &stateid, IOMODE_ANY, true);
 out_put_layout_hdr:
+	pnfs_free_lseg_list(&tmp_list);
 	pnfs_put_layout_hdr(lo);
 out:
 	dprintk("<-- %s status: %d\n", __func__, status);

include/linux/nfs4.h

@@ -282,7 +282,7 @@ enum nfsstat4 {
 
 static inline bool seqid_mutating_err(u32 err)
 {
-	/* rfc 3530 section 8.1.5: */
+	/* See RFC 7530, section 9.1.7 */
 	switch (err) {
 	case NFS4ERR_STALE_CLIENTID:
 	case NFS4ERR_STALE_STATEID:
@@ -291,6 +291,7 @@ static inline bool seqid_mutating_err(u32 err)
 	case NFS4ERR_BADXDR:
 	case NFS4ERR_RESOURCE:
 	case NFS4ERR_NOFILEHANDLE:
+	case NFS4ERR_MOVED:
 		return false;
 	};
 	return true;

include/linux/sunrpc/clnt.h

@@ -216,5 +216,6 @@ void rpc_clnt_xprt_switch_put(struct rpc_clnt *);
 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *, struct rpc_xprt *);
 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
 			const struct sockaddr *sap);
+void rpc_cleanup_clids(void);
 #endif /* __KERNEL__ */
 #endif /* _LINUX_SUNRPC_CLNT_H */

net/sunrpc/clnt.c

@@ -336,6 +336,11 @@ static int rpc_client_register(struct rpc_clnt *clnt,
 
 static DEFINE_IDA(rpc_clids);
 
+void rpc_cleanup_clids(void)
+{
+	ida_destroy(&rpc_clids);
+}
+
 static int rpc_alloc_clid(struct rpc_clnt *clnt)
 {
 	int clid;

net/sunrpc/sunrpc_syms.c

@@ -119,6 +119,7 @@ init_sunrpc(void)
 static void __exit
 cleanup_sunrpc(void)
 {
+	rpc_cleanup_clids();
 	rpcauth_remove_module();
 	cleanup_socket_xprt();
 	svc_cleanup_xprt_sock();