Merge tag 'nfsd-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:
 "The bulk of the patches for this release are clean-ups and minor bug
  fixes.

  There is one significant revert to mention: support for RDMA Read
  operations in the server's RPC-over-RDMA transport implementation has
  been fixed so it waits for Read completion in a way that avoids tying
  up an nfsd thread. This prevents a possible DoS vector if an
  RPC-over-RDMA client should become unresponsive during RDMA Read
  operations.

  As always I am grateful to NFSD contributors, reviewers, and testers"

* tag 'nfsd-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (56 commits)
  nfsd: rename nfsd_last_thread() to nfsd_destroy_serv()
  SUNRPC: discard sv_refcnt, and svc_get/svc_put
  svc: don't hold reference for poolstats, only mutex.
  SUNRPC: remove printk when back channel request not found
  svcrdma: Implement multi-stage Read completion again
  svcrdma: Copy construction of svc_rqst::rq_arg to rdma_read_complete()
  svcrdma: Add back svcxprt_rdma::sc_read_complete_q
  svcrdma: Add back svc_rdma_recv_ctxt::rc_pages
  svcrdma: Clean up comment in svc_rdma_accept()
  svcrdma: Remove queue-shortening warnings
  svcrdma: Remove pointer addresses shown in dprintk()
  svcrdma: Optimize svc_rdma_cc_init()
  svcrdma: De-duplicate completion ID initialization helpers
  svcrdma: Move the svc_rdma_cc_init() call
  svcrdma: Remove struct svc_rdma_read_info
  svcrdma: Update the synopsis of svc_rdma_read_special()
  svcrdma: Update the synopsis of svc_rdma_read_call_chunk()
  svcrdma: Update synopsis of svc_rdma_read_multiple_chunks()
  svcrdma: Update synopsis of svc_rdma_copy_inline_range()
  svcrdma: Update the synopsis of svc_rdma_read_data_item()
  ...

Author: torvalds

fs/lockd/svc.c

@@ -345,10 +345,10 @@ static int lockd_get(void)
 
 	serv->sv_maxconn = nlm_max_connections;
 	error = svc_set_num_threads(serv, NULL, 1);
-	/* The thread now holds the only reference */
-	svc_put(serv);
-	if (error < 0)
+	if (error < 0) {
+		svc_destroy(&serv);
 		return error;
+	}
 
 	nlmsvc_serv = serv;
 	register_inetaddr_notifier(&lockd_inetaddr_notifier);
@@ -372,11 +372,9 @@ static void lockd_put(void)
 	unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
 #endif
 
-	svc_get(nlmsvc_serv);
 	svc_set_num_threads(nlmsvc_serv, NULL, 0);
-	svc_put(nlmsvc_serv);
 	timer_delete_sync(&nlmsvc_retry);
-	nlmsvc_serv = NULL;
+	svc_destroy(&nlmsvc_serv);
 	dprintk("lockd_down: service destroyed\n");
 }
 

fs/nfs/callback.c

@@ -187,7 +187,7 @@ static struct svc_serv *nfs_callback_create_svc(int minorversion)
 	 * Check whether we're already up and running.
 	 */
 	if (cb_info->serv)
-		return svc_get(cb_info->serv);
+		return cb_info->serv;
 
 	/*
 	 * Sanity check: if there's no task,
@@ -245,9 +245,10 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 
 	cb_info->users++;
 err_net:
-	if (!cb_info->users)
-		cb_info->serv = NULL;
-	svc_put(serv);
+	if (!cb_info->users) {
+		svc_set_num_threads(cb_info->serv, NULL, 0);
+		svc_destroy(&cb_info->serv);
+	}
 err_create:
 	mutex_unlock(&nfs_callback_mutex);
 	return ret;
@@ -271,11 +272,9 @@ void nfs_callback_down(int minorversion, struct net *net)
 	nfs_callback_down_net(minorversion, serv, net);
 	cb_info->users--;
 	if (cb_info->users == 0) {
-		svc_get(serv);
 		svc_set_num_threads(serv, NULL, 0);
-		svc_put(serv);
 		dprintk("nfs_callback_down: service destroyed\n");
-		cb_info->serv = NULL;
+		svc_destroy(&cb_info->serv);
 	}
 	mutex_unlock(&nfs_callback_mutex);
 }

fs/nfs/callback.h

@@ -19,25 +19,6 @@ enum nfs4_callback_procnum {
 	CB_COMPOUND = 1,
 };
 
-enum nfs4_callback_opnum {
-	OP_CB_GETATTR = 3,
-	OP_CB_RECALL  = 4,
-/* Callback operations new to NFSv4.1 */
-	OP_CB_LAYOUTRECALL  = 5,
-	OP_CB_NOTIFY        = 6,
-	OP_CB_PUSH_DELEG    = 7,
-	OP_CB_RECALL_ANY    = 8,
-	OP_CB_RECALLABLE_OBJ_AVAIL = 9,
-	OP_CB_RECALL_SLOT   = 10,
-	OP_CB_SEQUENCE      = 11,
-	OP_CB_WANTS_CANCELLED = 12,
-	OP_CB_NOTIFY_LOCK   = 13,
-	OP_CB_NOTIFY_DEVICEID = 14,
-/* Callback operations new to NFSv4.2 */
-	OP_CB_OFFLOAD = 15,
-	OP_CB_ILLEGAL = 10044,
-};
-
 struct nfs4_slot;
 struct cb_process_state {
 	__be32			drc_status;

fs/nfsd/Kconfig

@@ -158,3 +158,19 @@ config NFSD_V4_SECURITY_LABEL
 
 	If you do not wish to enable fine-grained security labels SELinux or
 	Smack policies on NFSv4 files, say N.
+
+config NFSD_LEGACY_CLIENT_TRACKING
+	bool "Support legacy NFSv4 client tracking methods (DEPRECATED)"
+	depends on NFSD_V4
+	default n
+	help
+	  The NFSv4 server needs to store a small amount of information on
+	  stable storage in order to handle state recovery after reboot. Most
+	  modern deployments upcall to a userland daemon for this (nfsdcld),
+	  but older NFS servers may store information directly in a
+	  recoverydir, or spawn a process directly using a usermodehelper
+	  upcall.
+
+	  These legacy client tracking methods have proven to be probelmatic
+	  and will be removed in the future. Say Y here if you need support
+	  for them in the interim.

fs/nfsd/filecache.c

@@ -717,7 +717,7 @@ nfsd_file_cache_init(void)
 		return ret;
 
 	ret = -ENOMEM;
-	nfsd_filecache_wq = alloc_workqueue("nfsd_filecache", 0, 0);
+	nfsd_filecache_wq = alloc_workqueue("nfsd_filecache", WQ_UNBOUND, 0);
 	if (!nfsd_filecache_wq)
 		goto out;
 

fs/nfsd/netns.h

@@ -123,14 +123,9 @@ struct nfsd_net {
 	u32 clientid_counter;
 	u32 clverifier_counter;
 
-	struct svc_serv *nfsd_serv;
-	/* When a listening socket is added to nfsd, keep_active is set
-	 * and this justifies a reference on nfsd_serv.  This stops
-	 * nfsd_serv from being freed.  When the number of threads is
-	 * set, keep_active is cleared and the reference is dropped.  So
-	 * when the last thread exits, the service will be destroyed.
-	 */
-	int keep_active;
+	struct svc_info nfsd_info;
+#define nfsd_serv nfsd_info.serv
+
 
 	/*
 	 * clientid and stateid data for construction of net unique COPY

fs/nfsd/nfs4callback.c

@@ -31,6 +31,7 @@
  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <linux/nfs4.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/xprt.h>
 #include <linux/sunrpc/svc_xprt.h>
@@ -87,31 +88,6 @@ static void encode_bitmap4(struct xdr_stream *xdr, const __u32 *bitmap,
 	WARN_ON_ONCE(xdr_stream_encode_uint32_array(xdr, bitmap, len) < 0);
 }
 
-/*
- *	nfs_cb_opnum4
- *
- *	enum nfs_cb_opnum4 {
- *		OP_CB_GETATTR		= 3,
- *		  ...
- *	};
- */
-enum nfs_cb_opnum4 {
-	OP_CB_GETATTR			= 3,
-	OP_CB_RECALL			= 4,
-	OP_CB_LAYOUTRECALL		= 5,
-	OP_CB_NOTIFY			= 6,
-	OP_CB_PUSH_DELEG		= 7,
-	OP_CB_RECALL_ANY		= 8,
-	OP_CB_RECALLABLE_OBJ_AVAIL	= 9,
-	OP_CB_RECALL_SLOT		= 10,
-	OP_CB_SEQUENCE			= 11,
-	OP_CB_WANTS_CANCELLED		= 12,
-	OP_CB_NOTIFY_LOCK		= 13,
-	OP_CB_NOTIFY_DEVICEID		= 14,
-	OP_CB_OFFLOAD			= 15,
-	OP_CB_ILLEGAL			= 10044
-};
-
 static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op)
 {
 	__be32 *p;

fs/nfsd/nfs4proc.c

@@ -970,8 +970,11 @@ nfsd4_read(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	 * To ensure proper ordering, we therefore turn off zero copy if
 	 * the client wants us to do more in this compound:
 	 */
-	if (!nfsd4_last_compound_op(rqstp))
-		clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
+	if (!nfsd4_last_compound_op(rqstp)) {
+		struct nfsd4_compoundargs *argp = rqstp->rq_argp;
+
+		argp->splice_ok = false;
+	}
 
 	/* check stateid */
 	status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->current_fh,