NFSv4: Place the GETATTR operation before the CLOSE

In order to benefit from the DENY share lock protection, we should
put the GETATTR operation before the CLOSE. Otherwise, we might race
with a Windows machine that thinks it is now safe to modify the file.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/nfs4proc.c

@@ -3147,7 +3147,7 @@ static void nfs4_close_done(struct rpc_task *task, void *data)
 			res_stateid, calldata->arg.fmode);
 out_release:
 	nfs_release_seqid(calldata->arg.seqid);
-	nfs_refresh_inode(calldata->inode, calldata->res.fattr);
+	nfs_refresh_inode(calldata->inode, &calldata->fattr);
 	dprintk("%s: done, ret = %d!\n", __func__, task->tk_status);
 }
 
@@ -3215,7 +3215,10 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data)
 		nfs4_map_atomic_open_share(NFS_SERVER(inode),
 				calldata->arg.fmode, 0);
 
-	nfs_fattr_init(calldata->res.fattr);
+	if (calldata->res.fattr == NULL)
+		calldata->arg.bitmask = NULL;
+	else if (calldata->arg.bitmask == NULL)
+		calldata->res.fattr = NULL;
 	calldata->timestamp = jiffies;
 	if (nfs4_setup_sequence(NFS_SERVER(inode),
 				&calldata->arg.seq_args,
@@ -3282,6 +3285,7 @@ int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait)
 	calldata->arg.seqid = alloc_seqid(&state->owner->so_seqid, gfp_mask);
 	if (IS_ERR(calldata->arg.seqid))
 		goto out_free_calldata;
+	nfs_fattr_init(&calldata->fattr);
 	calldata->arg.fmode = 0;
 	calldata->lr.arg.ld_private = &calldata->lr.ld_private;
 	calldata->res.fattr = &calldata->fattr;

fs/nfs/nfs4xdr.c

@@ -2279,9 +2279,9 @@ static void nfs4_xdr_enc_close(struct rpc_rqst *req, struct xdr_stream *xdr,
 	encode_putfh(xdr, args->fh, &hdr);
 	if (args->lr_args)
 		encode_layoutreturn(xdr, args->lr_args, &hdr);
-	encode_close(xdr, args, &hdr);
 	if (args->bitmask != NULL)
 		encode_getfattr(xdr, args->bitmask, &hdr);
+	encode_close(xdr, args, &hdr);
 	encode_nops(&hdr);
 }
 
@@ -6494,16 +6494,12 @@ static int nfs4_xdr_dec_close(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
 		if (status)
 			goto out;
 	}
+	if (res->fattr != NULL) {
+		status = decode_getfattr(xdr, res->fattr, res->server);
+		if (status != 0)
+			goto out;
+	}
 	status = decode_close(xdr, res);
-	if (status != 0)
-		goto out;
-	/*
-	 * Note: Server may do delete on close for this file
-	 * 	in which case the getattr call will fail with
-	 * 	an ESTALE error. Shouldn't be a problem,
-	 * 	though, since fattr->valid will remain unset.
-	 */
-	decode_getfattr(xdr, res->fattr, res->server);
 out:
 	return status;
 }