NFS client bugfixes for Linux 5.1

Highlights include:
 
 Stable fixes:
 - Fix nfs4_lock_state refcounting in nfs4_alloc_{lock,unlock}data()
 - fix mount/umount race in nlmclnt.
 - NFSv4.1 don't free interrupted slot on open
 
 Bugfixes:
 - Don't let RPC_SOFTCONN tasks time out if the transport is connected
 - Fix a typo in nfs_init_timeout_values()
 - Fix layoutstats handling during read failovers
 - fix uninitialized variable warning
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Merge tag 'nfs-for-5.1-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - Fix nfs4_lock_state refcounting in nfs4_alloc_{lock,unlock}data()
   - fix mount/umount race in nlmclnt.
   - NFSv4.1 don't free interrupted slot on open

  Bugfixes:
   - Don't let RPC_SOFTCONN tasks time out if the transport is connected
   - Fix a typo in nfs_init_timeout_values()
   - Fix layoutstats handling during read failovers
   - fix uninitialized variable warning"

* tag 'nfs-for-5.1-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: fix uninitialized variable warning
  pNFS/flexfiles: Fix layoutstats handling during read failovers
  NFS: Fix a typo in nfs_init_timeout_values()
  SUNRPC: Don't let RPC_SOFTCONN tasks time out if the transport is connected
  NFSv4.1 don't free interrupted slot on open
  NFS: fix mount/umount race in nlmclnt.
  NFS: Fix nfs4_lock_state refcounting in nfs4_alloc_{lock,unlock}data()

fs/lockd/host.c

@@ -290,12 +290,11 @@ void nlmclnt_release_host(struct nlm_host *host)
 
 	WARN_ON_ONCE(host->h_server);
 
-	if (refcount_dec_and_test(&host->h_count)) {
+	if (refcount_dec_and_mutex_lock(&host->h_count, &nlm_host_mutex)) {
 		WARN_ON_ONCE(!list_empty(&host->h_lockowners));
 		WARN_ON_ONCE(!list_empty(&host->h_granted));
 		WARN_ON_ONCE(!list_empty(&host->h_reclaim));
 
-		mutex_lock(&nlm_host_mutex);
 		nlm_destroy_host_locked(host);
 		mutex_unlock(&nlm_host_mutex);
 	}

fs/nfs/client.c

@@ -453,7 +453,7 @@ void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 	case XPRT_TRANSPORT_RDMA:
 		if (retrans == NFS_UNSPEC_RETRANS)
 			to->to_retries = NFS_DEF_TCP_RETRANS;
-		if (timeo == NFS_UNSPEC_TIMEO || to->to_retries == 0)
+		if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
 			to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
 		if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
 			to->to_initval = NFS_MAX_TCP_TIMEOUT;

fs/nfs/flexfilelayout/flexfilelayout.c

@@ -1289,6 +1289,7 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 static int ff_layout_read_done_cb(struct rpc_task *task,
 				struct nfs_pgio_header *hdr)
 {
+	int new_idx = hdr->pgio_mirror_idx;
 	int err;
 
 	trace_nfs4_pnfs_read(hdr, task->tk_status);
@@ -1307,7 +1308,7 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 	case -NFS4ERR_RESET_TO_PNFS:
 		if (ff_layout_choose_best_ds_for_read(hdr->lseg,
 					hdr->pgio_mirror_idx + 1,
-					&hdr->pgio_mirror_idx))
+					&new_idx))
 			goto out_layouterror;
 		set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
 		return task->tk_status;
@@ -1320,7 +1321,9 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 
 	return 0;
 out_layouterror:
+	ff_layout_read_record_layoutstats_done(task, hdr);
 	ff_layout_send_layouterror(hdr->lseg);
+	hdr->pgio_mirror_idx = new_idx;
 out_eagain:
 	rpc_restart_call_prepare(task);
 	return -EAGAIN;

fs/nfs/nfs4proc.c

@@ -2933,7 +2933,8 @@ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
 	}
 
 out:
-	nfs4_sequence_free_slot(&opendata->o_res.seq_res);
+	if (!opendata->cancelled)
+		nfs4_sequence_free_slot(&opendata->o_res.seq_res);
 	return ret;
 }
 
@@ -6301,7 +6302,6 @@ static struct nfs4_unlockdata *nfs4_alloc_unlockdata(struct file_lock *fl,
 	p->arg.seqid = seqid;
 	p->res.seqid = seqid;
 	p->lsp = lsp;
-	refcount_inc(&lsp->ls_count);
 	/* Ensure we don't close file until we're done freeing locks! */
 	p->ctx = get_nfs_open_context(ctx);
 	p->l_ctx = nfs_get_lock_context(ctx);
@@ -6526,7 +6526,6 @@ static struct nfs4_lockdata *nfs4_alloc_lockdata(struct file_lock *fl,
 	p->res.lock_seqid = p->arg.lock_seqid;
 	p->lsp = lsp;
 	p->server = server;
-	refcount_inc(&lsp->ls_count);
 	p->ctx = get_nfs_open_context(ctx);
 	locks_init_lock(&p->fl);
 	locks_copy_lock(&p->fl, fl);

net/sunrpc/clnt.c

@@ -2311,6 +2311,15 @@ out_exit:
 	rpc_exit(task, status);
 }
 
+static bool
+rpc_check_connected(const struct rpc_rqst *req)
+{
+	/* No allocated request or transport? return true */
+	if (!req || !req->rq_xprt)
+		return true;
+	return xprt_connected(req->rq_xprt);
+}
+
 static void
 rpc_check_timeout(struct rpc_task *task)
 {
@@ -2322,10 +2331,11 @@ rpc_check_timeout(struct rpc_task *task)
 	dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
 	task->tk_timeouts++;
 
-	if (RPC_IS_SOFTCONN(task)) {
+	if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
 		rpc_exit(task, -ETIMEDOUT);
 		return;
 	}
+
 	if (RPC_IS_SOFT(task)) {
 		if (clnt->cl_chatty) {
 			printk(KERN_NOTICE "%s: server %s not responding, timed out\n",

net/sunrpc/xprtsock.c

@@ -495,8 +495,8 @@ xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 		int flags, struct rpc_rqst *req)
 {
 	struct xdr_buf *buf = &req->rq_private_buf;
-	size_t want, read;
-	ssize_t ret;
+	size_t want, uninitialized_var(read);
+	ssize_t uninitialized_var(ret);
 
 	xs_read_header(transport, buf);