X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lnet%2Flnet%2Fapi-ni.c;h=63eeacae7cf311be91662ae5f1456df65e045fee;hb=ed052504713d1db49531454a87055b2ee54399f0;hp=2db2d7a9955e221f58bb4cbbd6e85462fcc5ca22;hpb=756abb9cf00b936b3d9149f50925b0e02ca0e4fd;p=fs%2Flustre-release.git

diff --git a/lnet/lnet/api-ni.c b/lnet/lnet/api-ni.c
index 2db2d7a..63eeaca 100644
--- a/lnet/lnet/api-ni.c
+++ b/lnet/lnet/api-ni.c
@@ -39,7 +39,14 @@
 
 #define D_LNI D_CONSOLE
 
-struct lnet the_lnet;		/* THE state of the network */
+/*
+ * initialize ln_api_mutex statically, since it needs to be used in
+ * discovery_set callback. That module parameter callback can be called
+ * before module init completes. The mutex needs to be ready for use then.
+ */
+struct lnet the_lnet = {
+	.ln_api_mutex = __MUTEX_INITIALIZER(the_lnet.ln_api_mutex),
+};		/* THE state of the network */
 EXPORT_SYMBOL(the_lnet);
 
 static char *ip2nets = "";
@@ -75,6 +82,13 @@ module_param_call(lnet_interfaces_max, intf_max_set, param_get_int,
 MODULE_PARM_DESC(lnet_interfaces_max,
 		"Maximum number of interfaces in a node.");
 
+unsigned lnet_peer_discovery_disabled = 0;
+static int discovery_set(const char *val, struct kernel_param *kp);
+module_param_call(lnet_peer_discovery_disabled, discovery_set, param_get_int,
+		  &lnet_peer_discovery_disabled, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(lnet_peer_discovery_disabled,
+		"Set to 1 to disable peer discovery on this node.");
+
 /*
  * This sequence number keeps track of how many times DLC was used to
  * update the local NIs. It is incremented when a NI is added or
@@ -87,6 +101,59 @@ static atomic_t lnet_dlc_seq_no = ATOMIC_INIT(0);
 static int lnet_ping(struct lnet_process_id id, signed long timeout,
 		     struct lnet_process_id __user *ids, int n_ids);
 
+static int lnet_discover(lnet_process_id_t id, __u32 force,
+			 lnet_process_id_t __user *ids, int n_ids);
+
+static int
+discovery_set(const char *val, struct kernel_param *kp)
+{
+	int rc;
+	unsigned *discovery = (unsigned *)kp->arg;
+	unsigned long value;
+	struct lnet_ping_buffer *pbuf;
+
+	rc = kstrtoul(val, 0, &value);
+	if (rc) {
+		CERROR("Invalid module parameter value for 'lnet_peer_discovery_disabled'\n");
+		return rc;
+	}
+
+	value = (value) ? 1 : 0;
+
+	/*
+	 * The purpose of locking the api_mutex here is to ensure that
+	 * the correct value ends up stored properly.
+	 */
+	mutex_lock(&the_lnet.ln_api_mutex);
+
+	if (value == *discovery) {
+		mutex_unlock(&the_lnet.ln_api_mutex);
+		return 0;
+	}
+
+	*discovery = value;
+
+	if (the_lnet.ln_state != LNET_STATE_RUNNING) {
+		mutex_unlock(&the_lnet.ln_api_mutex);
+		return 0;
+	}
+
+	/* tell peers that discovery setting has changed */
+	lnet_net_lock(LNET_LOCK_EX);
+	pbuf = the_lnet.ln_ping_target;
+	if (value)
+		pbuf->pb_info.pi_features &= ~LNET_PING_FEAT_DISCOVERY;
+	else
+		pbuf->pb_info.pi_features |= LNET_PING_FEAT_DISCOVERY;
+	lnet_net_unlock(LNET_LOCK_EX);
+
+	lnet_push_update_to_peers(1);
+
+	mutex_unlock(&the_lnet.ln_api_mutex);
+
+	return 0;
+}
+
 static int
 intf_max_set(const char *val, struct kernel_param *kp)
 {
@@ -145,7 +212,6 @@ lnet_init_locks(void)
 	init_waitqueue_head(&the_lnet.ln_eq_waitq);
 	init_waitqueue_head(&the_lnet.ln_rc_waitq);
 	mutex_init(&the_lnet.ln_lnd_mutex);
-	mutex_init(&the_lnet.ln_api_mutex);
 }
 
 static void
@@ -356,6 +422,43 @@ static void lnet_assert_wire_constants(void)
 	CLASSERT((int)sizeof(((struct lnet_hdr *)0)->msg.hello.incarnation) == 8);
 	CLASSERT((int)offsetof(struct lnet_hdr, msg.hello.type) == 40);
 	CLASSERT((int)sizeof(((struct lnet_hdr *)0)->msg.hello.type) == 4);
+
+	/* Checks for struct lnet_ni_status and related constants */
+	CLASSERT(LNET_NI_STATUS_INVALID == 0x00000000);
+	CLASSERT(LNET_NI_STATUS_UP == 0x15aac0de);
+	CLASSERT(LNET_NI_STATUS_DOWN == 0xdeadface);
+
+	/* Checks for struct lnet_ni_status */
+	CLASSERT((int)sizeof(struct lnet_ni_status) == 16);
+	CLASSERT((int)offsetof(struct lnet_ni_status, ns_nid) == 0);
+	CLASSERT((int)sizeof(((struct lnet_ni_status *)0)->ns_nid) == 8);
+	CLASSERT((int)offsetof(struct lnet_ni_status, ns_status) == 8);
+	CLASSERT((int)sizeof(((struct lnet_ni_status *)0)->ns_status) == 4);
+	CLASSERT((int)offsetof(struct lnet_ni_status, ns_unused) == 12);
+	CLASSERT((int)sizeof(((struct lnet_ni_status *)0)->ns_unused) == 4);
+
+	/* Checks for struct lnet_ping_info and related constants */
+	CLASSERT(LNET_PROTO_PING_MAGIC == 0x70696E67);
+	CLASSERT(LNET_PING_FEAT_INVAL == 0);
+	CLASSERT(LNET_PING_FEAT_BASE == 1);
+	CLASSERT(LNET_PING_FEAT_NI_STATUS == 2);
+	CLASSERT(LNET_PING_FEAT_RTE_DISABLED == 4);
+	CLASSERT(LNET_PING_FEAT_MULTI_RAIL == 8);
+	CLASSERT(LNET_PING_FEAT_DISCOVERY == 16);
+	CLASSERT(LNET_PING_FEAT_BITS == 31);
+
+	/* Checks for struct lnet_ping_info */
+	CLASSERT((int)sizeof(struct lnet_ping_info) == 16);
+	CLASSERT((int)offsetof(struct lnet_ping_info, pi_magic) == 0);
+	CLASSERT((int)sizeof(((struct lnet_ping_info *)0)->pi_magic) == 4);
+	CLASSERT((int)offsetof(struct lnet_ping_info, pi_features) == 4);
+	CLASSERT((int)sizeof(((struct lnet_ping_info *)0)->pi_features) == 4);
+	CLASSERT((int)offsetof(struct lnet_ping_info, pi_pid) == 8);
+	CLASSERT((int)sizeof(((struct lnet_ping_info *)0)->pi_pid) == 4);
+	CLASSERT((int)offsetof(struct lnet_ping_info, pi_nnis) == 12);
+	CLASSERT((int)sizeof(((struct lnet_ping_info *)0)->pi_nnis) == 4);
+	CLASSERT((int)offsetof(struct lnet_ping_info, pi_ni) == 16);
+	CLASSERT((int)sizeof(((struct lnet_ping_info *)0)->pi_ni) == 0);
 }
 
 static struct lnet_lnd *lnet_find_lnd_by_type(__u32 type)
@@ -634,12 +737,15 @@ lnet_prepare(lnet_pid_t requested_pid)
 	the_lnet.ln_pid = requested_pid;
 
 	INIT_LIST_HEAD(&the_lnet.ln_test_peers);
-	INIT_LIST_HEAD(&the_lnet.ln_peers);
 	INIT_LIST_HEAD(&the_lnet.ln_remote_peer_ni_list);
 	INIT_LIST_HEAD(&the_lnet.ln_nets);
 	INIT_LIST_HEAD(&the_lnet.ln_routers);
 	INIT_LIST_HEAD(&the_lnet.ln_drop_rules);
 	INIT_LIST_HEAD(&the_lnet.ln_delay_rules);
+	INIT_LIST_HEAD(&the_lnet.ln_dc_request);
+	INIT_LIST_HEAD(&the_lnet.ln_dc_working);
+	INIT_LIST_HEAD(&the_lnet.ln_dc_expired);
+	init_waitqueue_head(&the_lnet.ln_dc_waitq);
 
 	rc = lnet_descriptor_setup();
 	if (rc != 0)
@@ -961,25 +1067,45 @@ lnet_count_acceptor_nets(void)
 	return count;
 }
 
-static struct lnet_ping_info *
-lnet_ping_info_create(int num_ni)
+struct lnet_ping_buffer *
+lnet_ping_buffer_alloc(int nnis, gfp_t gfp)
+{
+	struct lnet_ping_buffer *pbuf;
+
+	LIBCFS_ALLOC_GFP(pbuf, LNET_PING_BUFFER_SIZE(nnis), gfp);
+	if (pbuf) {
+		pbuf->pb_nnis = nnis;
+		atomic_set(&pbuf->pb_refcnt, 1);
+	}
+
+	return pbuf;
+}
+
+void
+lnet_ping_buffer_free(struct lnet_ping_buffer *pbuf)
+{
+	LASSERT(lnet_ping_buffer_numref(pbuf) == 0);
+	LIBCFS_FREE(pbuf, LNET_PING_BUFFER_SIZE(pbuf->pb_nnis));
+}
+
+static struct lnet_ping_buffer *
+lnet_ping_target_create(int nnis)
 {
-	struct lnet_ping_info *ping_info;
-	unsigned int	 infosz;
+	struct lnet_ping_buffer *pbuf;
 
-	infosz = offsetof(struct lnet_ping_info, pi_ni[num_ni]);
-	LIBCFS_ALLOC(ping_info, infosz);
-	if (ping_info == NULL) {
-		CERROR("Can't allocate ping info[%d]\n", num_ni);
+	pbuf = lnet_ping_buffer_alloc(nnis, GFP_NOFS);
+	if (pbuf == NULL) {
+		CERROR("Can't allocate ping source [%d]\n", nnis);
 		return NULL;
 	}
 
-	ping_info->pi_nnis = num_ni;
-	ping_info->pi_pid = the_lnet.ln_pid;
-	ping_info->pi_magic = LNET_PROTO_PING_MAGIC;
-	ping_info->pi_features = LNET_PING_FEAT_NI_STATUS;
+	pbuf->pb_info.pi_nnis = nnis;
+	pbuf->pb_info.pi_pid = the_lnet.ln_pid;
+	pbuf->pb_info.pi_magic = LNET_PROTO_PING_MAGIC;
+	pbuf->pb_info.pi_features =
+		LNET_PING_FEAT_NI_STATUS | LNET_PING_FEAT_MULTI_RAIL;
 
-	return ping_info;
+	return pbuf;
 }
 
 static inline int
@@ -1025,16 +1151,25 @@ lnet_get_ni_count(void)
 	return count;
 }
 
-static inline void
-lnet_ping_info_free(struct lnet_ping_info *pinfo)
+int
+lnet_ping_info_validate(struct lnet_ping_info *pinfo)
 {
-	LIBCFS_FREE(pinfo,
-		    offsetof(struct lnet_ping_info,
-			     pi_ni[pinfo->pi_nnis]));
+	if (!pinfo)
+		return -EINVAL;
+	if (pinfo->pi_magic != LNET_PROTO_PING_MAGIC)
+		return -EPROTO;
+	if (!(pinfo->pi_features & LNET_PING_FEAT_NI_STATUS))
+		return -EPROTO;
+	/* Loopback is guaranteed to be present */
+	if (pinfo->pi_nnis < 1 || pinfo->pi_nnis > lnet_interfaces_max)
+		return -ERANGE;
+	if (LNET_NETTYP(LNET_NIDNET(LNET_PING_INFO_LONI(pinfo))) != LOLND)
+		return -EPROTO;
+	return 0;
 }
 
 static void
-lnet_ping_info_destroy(void)
+lnet_ping_target_destroy(void)
 {
 	struct lnet_net *net;
 	struct lnet_ni	*ni;
@@ -1049,25 +1184,25 @@ lnet_ping_info_destroy(void)
 		}
 	}
 
-	lnet_ping_info_free(the_lnet.ln_ping_info);
-	the_lnet.ln_ping_info = NULL;
+	lnet_ping_buffer_decref(the_lnet.ln_ping_target);
+	the_lnet.ln_ping_target = NULL;
 
 	lnet_net_unlock(LNET_LOCK_EX);
 }
 
 static void
-lnet_ping_event_handler(struct lnet_event *event)
+lnet_ping_target_event_handler(struct lnet_event *event)
 {
-	struct lnet_ping_info *pinfo = event->md.user_ptr;
+	struct lnet_ping_buffer *pbuf = event->md.user_ptr;
 
 	if (event->unlinked)
-		pinfo->pi_features = LNET_PING_FEAT_INVAL;
+		lnet_ping_buffer_decref(pbuf);
 }
 
 static int
-lnet_ping_info_setup(struct lnet_ping_info **ppinfo,
-		     struct lnet_handle_md *md_handle,
-		     int ni_count, bool set_eq)
+lnet_ping_target_setup(struct lnet_ping_buffer **ppbuf,
+		       struct lnet_handle_md *ping_mdh,
+		       int ni_count, bool set_eq)
 {
 	struct lnet_process_id id = {
 		.nid = LNET_NID_ANY,
@@ -1078,72 +1213,76 @@ lnet_ping_info_setup(struct lnet_ping_info **ppinfo,
 	int rc, rc2;
 
 	if (set_eq) {
-		rc = LNetEQAlloc(0, lnet_ping_event_handler,
+		rc = LNetEQAlloc(0, lnet_ping_target_event_handler,
 				 &the_lnet.ln_ping_target_eq);
 		if (rc != 0) {
-			CERROR("Can't allocate ping EQ: %d\n", rc);
+			CERROR("Can't allocate ping buffer EQ: %d\n", rc);
 			return rc;
 		}
 	}
 
-	*ppinfo = lnet_ping_info_create(ni_count);
-	if (*ppinfo == NULL) {
+	*ppbuf = lnet_ping_target_create(ni_count);
+	if (*ppbuf == NULL) {
 		rc = -ENOMEM;
-		goto failed_0;
+		goto fail_free_eq;
 	}
 
+	/* Ping target ME/MD */
 	rc = LNetMEAttach(LNET_RESERVED_PORTAL, id,
 			  LNET_PROTO_PING_MATCHBITS, 0,
 			  LNET_UNLINK, LNET_INS_AFTER,
 			  &me_handle);
 	if (rc != 0) {
-		CERROR("Can't create ping ME: %d\n", rc);
-		goto failed_1;
+		CERROR("Can't create ping target ME: %d\n", rc);
+		goto fail_decref_ping_buffer;
 	}
 
 	/* initialize md content */
-	md.start     = *ppinfo;
-	md.length    = offsetof(struct lnet_ping_info,
-				pi_ni[(*ppinfo)->pi_nnis]);
+	md.start     = &(*ppbuf)->pb_info;
+	md.length    = LNET_PING_INFO_SIZE((*ppbuf)->pb_nnis);
 	md.threshold = LNET_MD_THRESH_INF;
 	md.max_size  = 0;
 	md.options   = LNET_MD_OP_GET | LNET_MD_TRUNCATE |
 		       LNET_MD_MANAGE_REMOTE;
-	md.user_ptr  = NULL;
 	md.eq_handle = the_lnet.ln_ping_target_eq;
-	md.user_ptr = *ppinfo;
+	md.user_ptr  = *ppbuf;
 
-	rc = LNetMDAttach(me_handle, md, LNET_RETAIN, md_handle);
+	rc = LNetMDAttach(me_handle, md, LNET_RETAIN, ping_mdh);
 	if (rc != 0) {
-		CERROR("Can't attach ping MD: %d\n", rc);
-		goto failed_2;
+		CERROR("Can't attach ping target MD: %d\n", rc);
+		goto fail_unlink_ping_me;
 	}
+	lnet_ping_buffer_addref(*ppbuf);
 
 	return 0;
 
-failed_2:
+fail_unlink_ping_me:
 	rc2 = LNetMEUnlink(me_handle);
 	LASSERT(rc2 == 0);
-failed_1:
-	lnet_ping_info_free(*ppinfo);
-	*ppinfo = NULL;
-failed_0:
-	if (set_eq)
-		LNetEQFree(the_lnet.ln_ping_target_eq);
+fail_decref_ping_buffer:
+	LASSERT(lnet_ping_buffer_numref(*ppbuf) == 1);
+	lnet_ping_buffer_decref(*ppbuf);
+	*ppbuf = NULL;
+fail_free_eq:
+	if (set_eq) {
+		rc2 = LNetEQFree(the_lnet.ln_ping_target_eq);
+		LASSERT(rc2 == 0);
+	}
 	return rc;
 }
 
 static void
-lnet_ping_md_unlink(struct lnet_ping_info *pinfo, struct lnet_handle_md *md_handle)
+lnet_ping_md_unlink(struct lnet_ping_buffer *pbuf,
+		    struct lnet_handle_md *ping_mdh)
 {
 	sigset_t	blocked = cfs_block_allsigs();
 
-	LNetMDUnlink(*md_handle);
-	LNetInvalidateMDHandle(md_handle);
+	LNetMDUnlink(*ping_mdh);
+	LNetInvalidateMDHandle(ping_mdh);
 
-	/* NB md could be busy; this just starts the unlink */
-	while (pinfo->pi_features != LNET_PING_FEAT_INVAL) {
-		CDEBUG(D_NET, "Still waiting for ping MD to unlink\n");
+	/* NB the MD could be busy; this just starts the unlink */
+	while (lnet_ping_buffer_numref(pbuf) > 1) {
+		CDEBUG(D_NET, "Still waiting for ping data MD to unlink\n");
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		schedule_timeout(cfs_time_seconds(1));
 	}
@@ -1152,63 +1291,84 @@ lnet_ping_md_unlink(struct lnet_ping_info *pinfo, struct lnet_handle_md *md_hand
 }
 
 static void
-lnet_ping_info_install_locked(struct lnet_ping_info *ping_info)
+lnet_ping_target_install_locked(struct lnet_ping_buffer *pbuf)
 {
-	int			i;
 	struct lnet_ni		*ni;
 	struct lnet_net		*net;
 	struct lnet_ni_status *ns;
+	int			i;
+	int			rc;
 
 	i = 0;
 	list_for_each_entry(net, &the_lnet.ln_nets, net_list) {
 		list_for_each_entry(ni, &net->net_ni_list, ni_netlist) {
-			LASSERT(i < ping_info->pi_nnis);
+			LASSERT(i < pbuf->pb_nnis);
 
-			ns = &ping_info->pi_ni[i];
+			ns = &pbuf->pb_info.pi_ni[i];
 
 			ns->ns_nid = ni->ni_nid;
 
 			lnet_ni_lock(ni);
 			ns->ns_status = (ni->ni_status != NULL) ?
-					ni->ni_status->ns_status :
+					 ni->ni_status->ns_status :
 						LNET_NI_STATUS_UP;
 			ni->ni_status = ns;
 			lnet_ni_unlock(ni);
 
 			i++;
 		}
-
 	}
+	/*
+	 * We (ab)use the ns_status of the loopback interface to
+	 * transmit the sequence number. The first interface listed
+	 * must be the loopback interface.
+	 */
+	rc = lnet_ping_info_validate(&pbuf->pb_info);
+	if (rc) {
+		LCONSOLE_EMERG("Invalid ping target: %d\n", rc);
+		LBUG();
+	}
+	LNET_PING_BUFFER_SEQNO(pbuf) =
+		atomic_inc_return(&the_lnet.ln_ping_target_seqno);
 }
 
 static void
-lnet_ping_target_update(struct lnet_ping_info *pinfo,
-			struct lnet_handle_md md_handle)
+lnet_ping_target_update(struct lnet_ping_buffer *pbuf,
+			struct lnet_handle_md ping_mdh)
 {
-	struct lnet_ping_info *old_pinfo = NULL;
-	struct lnet_handle_md old_md;
+	struct lnet_ping_buffer *old_pbuf = NULL;
+	struct lnet_handle_md old_ping_md;
 
 	/* switch the NIs to point to the new ping info created */
 	lnet_net_lock(LNET_LOCK_EX);
 
 	if (!the_lnet.ln_routing)
-		pinfo->pi_features |= LNET_PING_FEAT_RTE_DISABLED;
-	lnet_ping_info_install_locked(pinfo);
+		pbuf->pb_info.pi_features |= LNET_PING_FEAT_RTE_DISABLED;
+	if (!lnet_peer_discovery_disabled)
+		pbuf->pb_info.pi_features |= LNET_PING_FEAT_DISCOVERY;
+
+	/* Ensure only known feature bits have been set. */
+	LASSERT(pbuf->pb_info.pi_features & LNET_PING_FEAT_BITS);
+	LASSERT(!(pbuf->pb_info.pi_features & ~LNET_PING_FEAT_BITS));
+
+	lnet_ping_target_install_locked(pbuf);
 
-	if (the_lnet.ln_ping_info != NULL) {
-		old_pinfo = the_lnet.ln_ping_info;
-		old_md = the_lnet.ln_ping_target_md;
+	if (the_lnet.ln_ping_target) {
+		old_pbuf = the_lnet.ln_ping_target;
+		old_ping_md = the_lnet.ln_ping_target_md;
 	}
-	the_lnet.ln_ping_target_md = md_handle;
-	the_lnet.ln_ping_info = pinfo;
+	the_lnet.ln_ping_target_md = ping_mdh;
+	the_lnet.ln_ping_target = pbuf;
 
 	lnet_net_unlock(LNET_LOCK_EX);
 
-	if (old_pinfo != NULL) {
-		/* unlink the old ping info */
-		lnet_ping_md_unlink(old_pinfo, &old_md);
-		lnet_ping_info_free(old_pinfo);
+	if (old_pbuf) {
+		/* unlink and free the old ping info */
+		lnet_ping_md_unlink(old_pbuf, &old_ping_md);
+		lnet_ping_buffer_decref(old_pbuf);
 	}
+
+	lnet_push_update_to_peers(0);
 }
 
 static void
@@ -1216,13 +1376,156 @@ lnet_ping_target_fini(void)
 {
 	int		rc;
 
-	lnet_ping_md_unlink(the_lnet.ln_ping_info,
+	lnet_ping_md_unlink(the_lnet.ln_ping_target,
 			    &the_lnet.ln_ping_target_md);
 
 	rc = LNetEQFree(the_lnet.ln_ping_target_eq);
 	LASSERT(rc == 0);
 
-	lnet_ping_info_destroy();
+	lnet_ping_target_destroy();
+}
+
+/* Resize the push target. */
+int lnet_push_target_resize(void)
+{
+	lnet_process_id_t id = { LNET_NID_ANY, LNET_PID_ANY };
+	lnet_md_t md = { NULL };
+	lnet_handle_me_t meh;
+	lnet_handle_md_t mdh;
+	lnet_handle_md_t old_mdh;
+	struct lnet_ping_buffer *pbuf;
+	struct lnet_ping_buffer *old_pbuf;
+	int nnis = the_lnet.ln_push_target_nnis;
+	int rc;
+
+	if (nnis <= 0) {
+		rc = -EINVAL;
+		goto fail_return;
+	}
+again:
+	pbuf = lnet_ping_buffer_alloc(nnis, GFP_NOFS);
+	if (!pbuf) {
+		rc = -ENOMEM;
+		goto fail_return;
+	}
+
+	rc = LNetMEAttach(LNET_RESERVED_PORTAL, id,
+			  LNET_PROTO_PING_MATCHBITS, 0,
+			  LNET_UNLINK, LNET_INS_AFTER,
+			  &meh);
+	if (rc) {
+		CERROR("Can't create push target ME: %d\n", rc);
+		goto fail_decref_pbuf;
+	}
+
+	/* initialize md content */
+	md.start     = &pbuf->pb_info;
+	md.length    = LNET_PING_INFO_SIZE(nnis);
+	md.threshold = LNET_MD_THRESH_INF;
+	md.max_size  = 0;
+	md.options   = LNET_MD_OP_PUT | LNET_MD_TRUNCATE |
+		       LNET_MD_MANAGE_REMOTE;
+	md.user_ptr  = pbuf;
+	md.eq_handle = the_lnet.ln_push_target_eq;
+
+	rc = LNetMDAttach(meh, md, LNET_RETAIN, &mdh);
+	if (rc) {
+		CERROR("Can't attach push MD: %d\n", rc);
+		goto fail_unlink_meh;
+	}
+	lnet_ping_buffer_addref(pbuf);
+
+	lnet_net_lock(LNET_LOCK_EX);
+	old_pbuf = the_lnet.ln_push_target;
+	old_mdh = the_lnet.ln_push_target_md;
+	the_lnet.ln_push_target = pbuf;
+	the_lnet.ln_push_target_md = mdh;
+	lnet_net_unlock(LNET_LOCK_EX);
+
+	if (old_pbuf) {
+		LNetMDUnlink(old_mdh);
+		lnet_ping_buffer_decref(old_pbuf);
+	}
+
+	if (nnis < the_lnet.ln_push_target_nnis)
+		goto again;
+
+	CDEBUG(D_NET, "nnis %d success\n", nnis);
+
+	return 0;
+
+fail_unlink_meh:
+	LNetMEUnlink(meh);
+fail_decref_pbuf:
+	lnet_ping_buffer_decref(pbuf);
+fail_return:
+	CDEBUG(D_NET, "nnis %d error %d\n", nnis, rc);
+	return rc;
+}
+
+static void lnet_push_target_event_handler(struct lnet_event *ev)
+{
+	struct lnet_ping_buffer *pbuf = ev->md.user_ptr;
+
+	if (pbuf->pb_info.pi_magic == __swab32(LNET_PROTO_PING_MAGIC))
+		lnet_swap_pinginfo(pbuf);
+
+	lnet_peer_push_event(ev);
+	if (ev->unlinked)
+		lnet_ping_buffer_decref(pbuf);
+}
+
+/* Initialize the push target. */
+static int lnet_push_target_init(void)
+{
+	int rc;
+
+	if (the_lnet.ln_push_target)
+		return -EALREADY;
+
+	rc = LNetEQAlloc(0, lnet_push_target_event_handler,
+			 &the_lnet.ln_push_target_eq);
+	if (rc) {
+		CERROR("Can't allocated push target EQ: %d\n", rc);
+		return rc;
+	}
+
+	/* Start at the required minimum, we'll enlarge if required. */
+	the_lnet.ln_push_target_nnis = LNET_INTERFACES_MIN;
+
+	rc = lnet_push_target_resize();
+
+	if (rc) {
+		LNetEQFree(the_lnet.ln_push_target_eq);
+		LNetInvalidateEQHandle(&the_lnet.ln_push_target_eq);
+	}
+
+	return rc;
+}
+
+/* Clean up the push target. */
+static void lnet_push_target_fini(void)
+{
+	if (!the_lnet.ln_push_target)
+		return;
+
+	/* Unlink and invalidate to prevent new references. */
+	LNetMDUnlink(the_lnet.ln_push_target_md);
+	LNetInvalidateMDHandle(&the_lnet.ln_push_target_md);
+
+	/* Wait for the unlink to complete. */
+	while (lnet_ping_buffer_numref(the_lnet.ln_push_target) > 1) {
+		CDEBUG(D_NET, "Still waiting for ping data MD to unlink\n");
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(cfs_time_seconds(1));
+	}
+
+	lnet_ping_buffer_decref(the_lnet.ln_push_target);
+	the_lnet.ln_push_target = NULL;
+	the_lnet.ln_push_target_nnis = 0;
+
+	LNetEQFree(the_lnet.ln_push_target_eq);
+	LNetInvalidateEQHandle(&the_lnet.ln_push_target_eq);
 }
 
 static int
@@ -1731,8 +2034,6 @@ int lnet_lib_init(void)
 
 	lnet_assert_wire_constants();
 
-	memset(&the_lnet, 0, sizeof(the_lnet));
-
 	/* refer to global cfs_cpt_table for now */
 	the_lnet.ln_cpt_table	= cfs_cpt_table;
 	the_lnet.ln_cpt_number	= cfs_cpt_number(cfs_cpt_table);
@@ -1816,8 +2117,8 @@ LNetNIInit(lnet_pid_t requested_pid)
 	int			im_a_router = 0;
 	int			rc;
 	int			ni_count;
-	struct lnet_ping_info	*pinfo;
-	struct lnet_handle_md	md_handle;
+	struct lnet_ping_buffer	*pbuf;
+	struct lnet_handle_md	ping_mdh;
 	struct list_head	net_head;
 	struct lnet_net		*net;
 
@@ -1892,16 +2193,24 @@ LNetNIInit(lnet_pid_t requested_pid)
 	the_lnet.ln_refcount = 1;
 	/* Now I may use my own API functions... */
 
-	rc = lnet_ping_info_setup(&pinfo, &md_handle, ni_count, true);
+	rc = lnet_ping_target_setup(&pbuf, &ping_mdh, ni_count, true);
 	if (rc != 0)
 		goto err_acceptor_stop;
 
-	lnet_ping_target_update(pinfo, md_handle);
+	lnet_ping_target_update(pbuf, ping_mdh);
 
 	rc = lnet_router_checker_start();
 	if (rc != 0)
 		goto err_stop_ping;
 
+	rc = lnet_push_target_init();
+	if (rc != 0)
+		goto err_stop_router_checker;
+
+	rc = lnet_peer_discovery_start();
+	if (rc != 0)
+		goto err_destroy_push_target;
+
 	lnet_fault_init();
 	lnet_proc_init();
 
@@ -1909,6 +2218,10 @@ LNetNIInit(lnet_pid_t requested_pid)
 
 	return 0;
 
+err_destroy_push_target:
+	lnet_push_target_fini();
+err_stop_router_checker:
+	lnet_router_checker_stop();
 err_stop_ping:
 	lnet_ping_target_fini();
 err_acceptor_stop:
@@ -1958,6 +2271,8 @@ LNetNIFini()
 		lnet_fault_fini();
 
 		lnet_proc_fini();
+		lnet_peer_discovery_stop();
+		lnet_push_target_fini();
 		lnet_router_checker_stop();
 		lnet_ping_target_fini();
 
@@ -2006,15 +2321,22 @@ lnet_fill_ni_info(struct lnet_ni *ni, struct lnet_ioctl_config_ni *cfg_ni,
 	}
 
 	cfg_ni->lic_nid = ni->ni_nid;
-	cfg_ni->lic_status = ni->ni_status->ns_status;
+	if (LNET_NETTYP(LNET_NIDNET(ni->ni_nid)) == LOLND)
+		cfg_ni->lic_status = LNET_NI_STATUS_UP;
+	else
+		cfg_ni->lic_status = ni->ni_status->ns_status;
 	cfg_ni->lic_tcp_bonding = use_tcp_bonding;
 	cfg_ni->lic_dev_cpt = ni->ni_dev_cpt;
 
 	memcpy(&tun->lt_cmn, &ni->ni_net->net_tunables, sizeof(tun->lt_cmn));
 
 	if (stats) {
-		stats->iel_send_count = atomic_read(&ni->ni_stats.send_count);
-		stats->iel_recv_count = atomic_read(&ni->ni_stats.recv_count);
+		stats->iel_send_count = lnet_sum_stats(&ni->ni_stats,
+						       LNET_STATS_TYPE_SEND);
+		stats->iel_recv_count = lnet_sum_stats(&ni->ni_stats,
+						       LNET_STATS_TYPE_RECV);
+		stats->iel_drop_count = lnet_sum_stats(&ni->ni_stats,
+						       LNET_STATS_TYPE_DROP);
 	}
 
 	/*
@@ -2091,7 +2413,10 @@ lnet_fill_ni_info_legacy(struct lnet_ni *ni,
 	config->cfg_config_u.cfg_net.net_peer_rtr_credits =
 		ni->ni_net->net_tunables.lct_peer_rtr_credits;
 
-	net_config->ni_status = ni->ni_status->ns_status;
+	if (LNET_NETTYP(LNET_NIDNET(ni->ni_nid)) == LOLND)
+		net_config->ni_status = LNET_NI_STATUS_UP;
+	else
+		net_config->ni_status = ni->ni_status->ns_status;
 
 	if (ni->ni_cpts) {
 		int num_cpts = min(ni->ni_ncpts, LNET_MAX_SHOW_NUM_CPT);
@@ -2238,12 +2563,35 @@ lnet_get_ni_config(struct lnet_ioctl_config_ni *cfg_ni,
 	return rc;
 }
 
+int lnet_get_ni_stats(struct lnet_ioctl_element_msg_stats *msg_stats)
+{
+	struct lnet_ni *ni;
+	int cpt;
+	int rc = -ENOENT;
+
+	if (!msg_stats)
+		return -EINVAL;
+
+	cpt = lnet_net_lock_current();
+
+	ni = lnet_get_ni_idx_locked(msg_stats->im_idx);
+
+	if (ni) {
+		lnet_usr_translate_stats(msg_stats, &ni->ni_stats);
+		rc = 0;
+	}
+
+	lnet_net_unlock(cpt);
+
+	return rc;
+}
+
 static int lnet_add_net_common(struct lnet_net *net,
 			       struct lnet_ioctl_config_lnd_tunables *tun)
 {
 	__u32			net_id;
-	struct lnet_ping_info	*pinfo;
-	struct lnet_handle_md	md_handle;
+	struct lnet_ping_buffer *pbuf;
+	struct lnet_handle_md	ping_mdh;
 	int			rc;
 	struct lnet_remotenet *rnet;
 	int			net_ni_count;
@@ -2265,7 +2613,7 @@ static int lnet_add_net_common(struct lnet_net *net,
 
 	/*
 	 * make sure you calculate the correct number of slots in the ping
-	 * info. Since the ping info is a flattened list of all the NIs,
+	 * buffer. Since the ping info is a flattened list of all the NIs,
 	 * we should allocate enough slots to accomodate the number of NIs
 	 * which will be added.
 	 *
@@ -2274,9 +2622,9 @@ static int lnet_add_net_common(struct lnet_net *net,
 	 */
 	net_ni_count = lnet_get_net_ni_count_pre(net);
 
-	rc = lnet_ping_info_setup(&pinfo, &md_handle,
-				  net_ni_count + lnet_get_ni_count(),
-				  false);
+	rc = lnet_ping_target_setup(&pbuf, &ping_mdh,
+				    net_ni_count + lnet_get_ni_count(),
+				    false);
 	if (rc < 0) {
 		lnet_net_free(net);
 		return rc;
@@ -2327,13 +2675,13 @@ static int lnet_add_net_common(struct lnet_net *net,
 	lnet_peer_net_added(net);
 	lnet_net_unlock(LNET_LOCK_EX);
 
-	lnet_ping_target_update(pinfo, md_handle);
+	lnet_ping_target_update(pbuf, ping_mdh);
 
 	return 0;
 
 failed:
-	lnet_ping_md_unlink(pinfo, &md_handle);
-	lnet_ping_info_free(pinfo);
+	lnet_ping_md_unlink(pbuf, &ping_mdh);
+	lnet_ping_buffer_decref(pbuf);
 	return rc;
 }
 
@@ -2424,8 +2772,8 @@ int lnet_dyn_del_ni(struct lnet_ioctl_config_ni *conf)
 	struct lnet_net	 *net;
 	struct lnet_ni *ni;
 	__u32 net_id = LNET_NIDNET(conf->lic_nid);
-	struct lnet_ping_info *pinfo;
-	struct lnet_handle_md md_handle;
+	struct lnet_ping_buffer *pbuf;
+	struct lnet_handle_md  ping_mdh;
 	int		  rc;
 	int		  net_count;
 	__u32		  addr;
@@ -2443,7 +2791,7 @@ int lnet_dyn_del_ni(struct lnet_ioctl_config_ni *conf)
 		CERROR("net %s not found\n",
 		       libcfs_net2str(net_id));
 		rc = -ENOENT;
-		goto net_unlock;
+		goto unlock_net;
 	}
 
 	addr = LNET_NIDADDR(conf->lic_nid);
@@ -2454,28 +2802,28 @@ int lnet_dyn_del_ni(struct lnet_ioctl_config_ni *conf)
 		lnet_net_unlock(0);
 
 		/* create and link a new ping info, before removing the old one */
-		rc = lnet_ping_info_setup(&pinfo, &md_handle,
+		rc = lnet_ping_target_setup(&pbuf, &ping_mdh,
 					lnet_get_ni_count() - net_count,
 					false);
 		if (rc != 0)
-			goto out;
+			goto unlock_api_mutex;
 
 		lnet_shutdown_lndnet(net);
 
 		if (lnet_count_acceptor_nets() == 0)
 			lnet_acceptor_stop();
 
-		lnet_ping_target_update(pinfo, md_handle);
+		lnet_ping_target_update(pbuf, ping_mdh);
 
-		goto out;
+		goto unlock_api_mutex;
 	}
 
 	ni = lnet_nid2ni_locked(conf->lic_nid, 0);
 	if (!ni) {
-		CERROR("nid %s not found \n",
+		CERROR("nid %s not found\n",
 		       libcfs_nid2str(conf->lic_nid));
 		rc = -ENOENT;
-		goto net_unlock;
+		goto unlock_net;
 	}
 
 	net_count = lnet_get_net_ni_count_locked(net);
@@ -2483,27 +2831,27 @@ int lnet_dyn_del_ni(struct lnet_ioctl_config_ni *conf)
 	lnet_net_unlock(0);
 
 	/* create and link a new ping info, before removing the old one */
-	rc = lnet_ping_info_setup(&pinfo, &md_handle,
+	rc = lnet_ping_target_setup(&pbuf, &ping_mdh,
 				  lnet_get_ni_count() - 1, false);
 	if (rc != 0)
-		goto out;
+		goto unlock_api_mutex;
 
 	lnet_shutdown_lndni(ni);
 
 	if (lnet_count_acceptor_nets() == 0)
 		lnet_acceptor_stop();
 
-	lnet_ping_target_update(pinfo, md_handle);
+	lnet_ping_target_update(pbuf, ping_mdh);
 
 	/* check if the net is empty and remove it if it is */
 	if (net_count == 1)
 		lnet_shutdown_lndnet(net);
 
-	goto out;
+	goto unlock_api_mutex;
 
-net_unlock:
+unlock_net:
 	lnet_net_unlock(0);
-out:
+unlock_api_mutex:
 	mutex_unlock(&the_lnet.ln_api_mutex);
 
 	return rc;
@@ -2571,8 +2919,8 @@ int
 lnet_dyn_del_net(__u32 net_id)
 {
 	struct lnet_net	 *net;
-	struct lnet_ping_info *pinfo;
-	struct lnet_handle_md md_handle;
+	struct lnet_ping_buffer *pbuf;
+	struct lnet_handle_md ping_mdh;
 	int		  rc;
 	int		  net_ni_count;
 
@@ -2596,8 +2944,8 @@ lnet_dyn_del_net(__u32 net_id)
 	lnet_net_unlock(0);
 
 	/* create and link a new ping info, before removing the old one */
-	rc = lnet_ping_info_setup(&pinfo, &md_handle,
-				  lnet_get_ni_count() - net_ni_count, false);
+	rc = lnet_ping_target_setup(&pbuf, &ping_mdh,
+				    lnet_get_ni_count() - net_ni_count, false);
 	if (rc != 0)
 		goto out;
 
@@ -2606,7 +2954,7 @@ lnet_dyn_del_net(__u32 net_id)
 	if (lnet_count_acceptor_nets() == 0)
 		lnet_acceptor_stop();
 
-	lnet_ping_target_update(pinfo, md_handle);
+	lnet_ping_target_update(pbuf, ping_mdh);
 
 out:
 	mutex_unlock(&the_lnet.ln_api_mutex);
@@ -2705,9 +3053,10 @@ LNetCtl(unsigned int cmd, void *arg)
 		__u32 tun_size;
 
 		cfg_ni = arg;
+
 		/* get the tunables if they are available */
 		if (cfg_ni->lic_cfg_hdr.ioc_len <
-		    sizeof(*cfg_ni) + sizeof(*stats)+ sizeof(*tun))
+		    sizeof(*cfg_ni) + sizeof(*stats) + sizeof(*tun))
 			return -EINVAL;
 
 		stats = (struct lnet_ioctl_element_stats *)
@@ -2724,6 +3073,19 @@ LNetCtl(unsigned int cmd, void *arg)
 		return rc;
 	}
 
+	case IOC_LIBCFS_GET_LOCAL_NI_MSG_STATS: {
+		struct lnet_ioctl_element_msg_stats *msg_stats = arg;
+
+		if (msg_stats->im_hdr.ioc_len != sizeof(*msg_stats))
+			return -EINVAL;
+
+		mutex_lock(&the_lnet.ln_api_mutex);
+		rc = lnet_get_ni_stats(msg_stats);
+		mutex_unlock(&the_lnet.ln_api_mutex);
+
+		return rc;
+	}
+
 	case IOC_LIBCFS_GET_NET: {
 		size_t total = sizeof(*config) +
 			       sizeof(struct lnet_ioctl_net_config);
@@ -2784,22 +3146,22 @@ LNetCtl(unsigned int cmd, void *arg)
 		return rc;
 
 	case IOC_LIBCFS_SET_NUMA_RANGE: {
-		struct lnet_ioctl_numa_range *numa;
+		struct lnet_ioctl_set_value *numa;
 		numa = arg;
-		if (numa->nr_hdr.ioc_len != sizeof(*numa))
+		if (numa->sv_hdr.ioc_len != sizeof(*numa))
 			return -EINVAL;
-		mutex_lock(&the_lnet.ln_api_mutex);
-		lnet_numa_range = numa->nr_range;
-		mutex_unlock(&the_lnet.ln_api_mutex);
+		lnet_net_lock(LNET_LOCK_EX);
+		lnet_numa_range = numa->sv_value;
+		lnet_net_unlock(LNET_LOCK_EX);
 		return 0;
 	}
 
 	case IOC_LIBCFS_GET_NUMA_RANGE: {
-		struct lnet_ioctl_numa_range *numa;
+		struct lnet_ioctl_set_value *numa;
 		numa = arg;
-		if (numa->nr_hdr.ioc_len != sizeof(*numa))
+		if (numa->sv_hdr.ioc_len != sizeof(*numa))
 			return -EINVAL;
-		numa->nr_range = lnet_numa_range;
+		numa->sv_value = lnet_numa_range;
 		return 0;
 	}
 
@@ -2827,9 +3189,9 @@ LNetCtl(unsigned int cmd, void *arg)
 			return -EINVAL;
 
 		mutex_lock(&the_lnet.ln_api_mutex);
-		rc = lnet_add_peer_ni_to_peer(cfg->prcfg_prim_nid,
-					      cfg->prcfg_cfg_nid,
-					      cfg->prcfg_mr);
+		rc = lnet_add_peer_ni(cfg->prcfg_prim_nid,
+				      cfg->prcfg_cfg_nid,
+				      cfg->prcfg_mr);
 		mutex_unlock(&the_lnet.ln_api_mutex);
 		return rc;
 	}
@@ -2841,8 +3203,8 @@ LNetCtl(unsigned int cmd, void *arg)
 			return -EINVAL;
 
 		mutex_lock(&the_lnet.ln_api_mutex);
-		rc = lnet_del_peer_ni_from_peer(cfg->prcfg_prim_nid,
-						cfg->prcfg_cfg_nid);
+		rc = lnet_del_peer_ni(cfg->prcfg_prim_nid,
+				      cfg->prcfg_cfg_nid);
 		mutex_unlock(&the_lnet.ln_api_mutex);
 		return rc;
 	}
@@ -2871,21 +3233,30 @@ LNetCtl(unsigned int cmd, void *arg)
 
 	case IOC_LIBCFS_GET_PEER_NI: {
 		struct lnet_ioctl_peer_cfg *cfg = arg;
-		struct lnet_peer_ni_credit_info __user *lpni_cri;
-		struct lnet_ioctl_element_stats __user *lpni_stats;
-		size_t usr_size = sizeof(*lpni_cri) + sizeof(*lpni_stats);
 
-		if ((cfg->prcfg_hdr.ioc_len != sizeof(*cfg)) ||
-		    (cfg->prcfg_size != usr_size))
+		if (cfg->prcfg_hdr.ioc_len < sizeof(*cfg))
 			return -EINVAL;
 
-		lpni_cri = cfg->prcfg_bulk;
-		lpni_stats = cfg->prcfg_bulk + sizeof(*lpni_cri);
+		mutex_lock(&the_lnet.ln_api_mutex);
+		rc = lnet_get_peer_info(&cfg->prcfg_prim_nid,
+					&cfg->prcfg_cfg_nid,
+					&cfg->prcfg_count,
+					&cfg->prcfg_mr,
+					&cfg->prcfg_size,
+					(void __user *)cfg->prcfg_bulk);
+		mutex_unlock(&the_lnet.ln_api_mutex);
+		return rc;
+	}
+
+	case IOC_LIBCFS_GET_PEER_LIST: {
+		struct lnet_ioctl_peer_cfg *cfg = arg;
+
+		if (cfg->prcfg_hdr.ioc_len < sizeof(*cfg))
+			return -EINVAL;
 
 		mutex_lock(&the_lnet.ln_api_mutex);
-		rc = lnet_get_peer_info(cfg->prcfg_count, &cfg->prcfg_prim_nid,
-					&cfg->prcfg_cfg_nid, &cfg->prcfg_mr,
-					lpni_cri, lpni_stats);
+		rc = lnet_get_peer_list(&cfg->prcfg_count, &cfg->prcfg_size,
+				(lnet_process_id_t __user *)cfg->prcfg_bulk);
 		mutex_unlock(&the_lnet.ln_api_mutex);
 		return rc;
 	}
@@ -2923,24 +3294,69 @@ LNetCtl(unsigned int cmd, void *arg)
 		id.nid = data->ioc_nid;
 		id.pid = data->ioc_u32[0];
 
-		/* Don't block longer than 2 minutes */
-		if (data->ioc_u32[1] > 120 * MSEC_PER_SEC)
-			return -EINVAL;
-
-		/* If timestamp is negative then disable timeout */
-		if ((s32)data->ioc_u32[1] < 0)
-			timeout = MAX_SCHEDULE_TIMEOUT;
+		/* If timeout is negative then set default of 3 minutes */
+		if (((s32)data->ioc_u32[1] <= 0) ||
+		    data->ioc_u32[1] > (DEFAULT_PEER_TIMEOUT * MSEC_PER_SEC))
+			timeout = msecs_to_jiffies(DEFAULT_PEER_TIMEOUT * MSEC_PER_SEC);
 		else
 			timeout = msecs_to_jiffies(data->ioc_u32[1]);
 
 		rc = lnet_ping(id, timeout, data->ioc_pbuf1,
 			       data->ioc_plen1 / sizeof(struct lnet_process_id));
+
 		if (rc < 0)
 			return rc;
+
 		data->ioc_count = rc;
 		return 0;
 	}
 
+	case IOC_LIBCFS_PING_PEER: {
+		struct lnet_ioctl_ping_data *ping = arg;
+		struct lnet_peer *lp;
+		signed long timeout;
+
+		/* If timeout is negative then set default of 3 minutes */
+		if (((s32)ping->op_param) <= 0 ||
+		    ping->op_param > (DEFAULT_PEER_TIMEOUT * MSEC_PER_SEC))
+			timeout = msecs_to_jiffies(DEFAULT_PEER_TIMEOUT * MSEC_PER_SEC);
+		else
+			timeout = msecs_to_jiffies(ping->op_param);
+
+		rc = lnet_ping(ping->ping_id, timeout,
+			       ping->ping_buf,
+			       ping->ping_count);
+		if (rc < 0)
+			return rc;
+
+		lp = lnet_find_peer(ping->ping_id.nid);
+		if (lp) {
+			ping->ping_id.nid = lp->lp_primary_nid;
+			ping->mr_info = lnet_peer_is_multi_rail(lp);
+		}
+		ping->ping_count = rc;
+		return 0;
+	}
+
+	case IOC_LIBCFS_DISCOVER: {
+		struct lnet_ioctl_ping_data *discover = arg;
+		struct lnet_peer *lp;
+
+		rc = lnet_discover(discover->ping_id, discover->op_param,
+				   discover->ping_buf,
+				   discover->ping_count);
+		if (rc < 0)
+			return rc;
+		lp = lnet_find_peer(discover->ping_id.nid);
+		if (lp) {
+			discover->ping_id.nid = lp->lp_primary_nid;
+			discover->mr_info = lnet_peer_is_multi_rail(lp);
+		}
+
+		discover->ping_count = rc;
+		return 0;
+	}
+
 	default:
 		ni = lnet_net2ni_addref(data->ioc_net);
 		if (ni == NULL)
@@ -3044,8 +3460,7 @@ static int lnet_ping(struct lnet_process_id id, signed long timeout,
 	int unlinked = 0;
 	int replied = 0;
 	const signed long a_long_time = msecs_to_jiffies(60 * MSEC_PER_SEC);
-	int infosz;
-	struct lnet_ping_info *info;
+	struct lnet_ping_buffer *pbuf;
 	struct lnet_process_id tmpid;
 	int i;
 	int nob;
@@ -3053,8 +3468,6 @@ static int lnet_ping(struct lnet_process_id id, signed long timeout,
 	int rc2;
 	sigset_t blocked;
 
-	infosz = offsetof(struct lnet_ping_info, pi_ni[n_ids]);
-
 	/* n_ids limit is arbitrary */
 	if (n_ids <= 0 || n_ids > lnet_interfaces_max || id.nid == LNET_NID_ANY)
 		return -EINVAL;
@@ -3062,21 +3475,21 @@ static int lnet_ping(struct lnet_process_id id, signed long timeout,
 	if (id.pid == LNET_PID_ANY)
 		id.pid = LNET_PID_LUSTRE;
 
-	LIBCFS_ALLOC(info, infosz);
-	if (info == NULL)
+	pbuf = lnet_ping_buffer_alloc(n_ids, GFP_NOFS);
+	if (!pbuf)
 		return -ENOMEM;
 
 	/* NB 2 events max (including any unlink event) */
 	rc = LNetEQAlloc(2, LNET_EQ_HANDLER_NONE, &eqh);
 	if (rc != 0) {
 		CERROR("Can't allocate EQ: %d\n", rc);
-		goto out_0;
+		goto fail_ping_buffer_decref;
 	}
 
 	/* initialize md content */
-	md.start     = info;
-	md.length    = infosz;
-	md.threshold = 2; /*GET/REPLY*/
+	md.start     = &pbuf->pb_info;
+	md.length    = LNET_PING_INFO_SIZE(n_ids);
+	md.threshold = 2; /* GET/REPLY */
 	md.max_size  = 0;
 	md.options   = LNET_MD_TRUNCATE;
 	md.user_ptr  = NULL;
@@ -3085,7 +3498,7 @@ static int lnet_ping(struct lnet_process_id id, signed long timeout,
 	rc = LNetMDBind(md, LNET_UNLINK, &mdh);
 	if (rc != 0) {
 		CERROR("Can't bind MD: %d\n", rc);
-		goto out_1;
+		goto fail_free_eq;
 	}
 
 	rc = LNetGet(LNET_NID_ANY, mdh, id,
@@ -3094,7 +3507,6 @@ static int lnet_ping(struct lnet_process_id id, signed long timeout,
 
 	if (rc != 0) {
 		/* Don't CERROR; this could be deliberate! */
-
 		rc2 = LNetMDUnlink(mdh);
 		LASSERT(rc2 == 0);
 
@@ -3142,7 +3554,6 @@ static int lnet_ping(struct lnet_process_id id, signed long timeout,
 			replied = 1;
 			rc = event.mlength;
 		}
-
 	} while (rc2 <= 0 || !event.unlinked);
 
 	if (!replied) {
@@ -3150,68 +3561,146 @@ static int lnet_ping(struct lnet_process_id id, signed long timeout,
 			CWARN("%s: Unexpected rc >= 0 but no reply!\n",
 			      libcfs_id2str(id));
 		rc = -EIO;
-		goto out_1;
+		goto fail_free_eq;
 	}
 
 	nob = rc;
-	LASSERT(nob >= 0 && nob <= infosz);
+	LASSERT(nob >= 0 && nob <= LNET_PING_INFO_SIZE(n_ids));
 
-	rc = -EPROTO;				/* if I can't parse... */
+	rc = -EPROTO;		/* if I can't parse... */
 
 	if (nob < 8) {
-		/* can't check magic/version */
 		CERROR("%s: ping info too short %d\n",
 		       libcfs_id2str(id), nob);
-		goto out_1;
+		goto fail_free_eq;
 	}
 
-	if (info->pi_magic == __swab32(LNET_PROTO_PING_MAGIC)) {
-		lnet_swap_pinginfo(info);
-	} else if (info->pi_magic != LNET_PROTO_PING_MAGIC) {
+	if (pbuf->pb_info.pi_magic == __swab32(LNET_PROTO_PING_MAGIC)) {
+		lnet_swap_pinginfo(pbuf);
+	} else if (pbuf->pb_info.pi_magic != LNET_PROTO_PING_MAGIC) {
 		CERROR("%s: Unexpected magic %08x\n",
-		       libcfs_id2str(id), info->pi_magic);
-		goto out_1;
+		       libcfs_id2str(id), pbuf->pb_info.pi_magic);
+		goto fail_free_eq;
 	}
 
-	if ((info->pi_features & LNET_PING_FEAT_NI_STATUS) == 0) {
+	if ((pbuf->pb_info.pi_features & LNET_PING_FEAT_NI_STATUS) == 0) {
 		CERROR("%s: ping w/o NI status: 0x%x\n",
-		       libcfs_id2str(id), info->pi_features);
-		goto out_1;
+		       libcfs_id2str(id), pbuf->pb_info.pi_features);
+		goto fail_free_eq;
 	}
 
-	if (nob < offsetof(struct lnet_ping_info, pi_ni[0])) {
-		CERROR("%s: Short reply %d(%d min)\n", libcfs_id2str(id),
-		       nob, (int)offsetof(struct lnet_ping_info, pi_ni[0]));
-		goto out_1;
+	if (nob < LNET_PING_INFO_SIZE(0)) {
+		CERROR("%s: Short reply %d(%d min)\n",
+		       libcfs_id2str(id),
+		       nob, (int)LNET_PING_INFO_SIZE(0));
+		goto fail_free_eq;
 	}
 
-	if (info->pi_nnis < n_ids)
-		n_ids = info->pi_nnis;
+	if (pbuf->pb_info.pi_nnis < n_ids)
+		n_ids = pbuf->pb_info.pi_nnis;
 
-	if (nob < offsetof(struct lnet_ping_info, pi_ni[n_ids])) {
-		CERROR("%s: Short reply %d(%d expected)\n", libcfs_id2str(id),
-		       nob, (int)offsetof(struct lnet_ping_info, pi_ni[n_ids]));
-		goto out_1;
+	if (nob < LNET_PING_INFO_SIZE(n_ids)) {
+		CERROR("%s: Short reply %d(%d expected)\n",
+		       libcfs_id2str(id),
+		       nob, (int)LNET_PING_INFO_SIZE(n_ids));
+		goto fail_free_eq;
 	}
 
-	rc = -EFAULT;				/* If I SEGV... */
+	rc = -EFAULT;		/* if I segv in copy_to_user()... */
 
 	memset(&tmpid, 0, sizeof(tmpid));
 	for (i = 0; i < n_ids; i++) {
-		tmpid.pid = info->pi_pid;
-		tmpid.nid = info->pi_ni[i].ns_nid;
+		tmpid.pid = pbuf->pb_info.pi_pid;
+		tmpid.nid = pbuf->pb_info.pi_ni[i].ns_nid;
 		if (copy_to_user(&ids[i], &tmpid, sizeof(tmpid)))
-			goto out_1;
+			goto fail_free_eq;
 	}
-	rc = info->pi_nnis;
+	rc = pbuf->pb_info.pi_nnis;
 
- out_1:
+ fail_free_eq:
 	rc2 = LNetEQFree(eqh);
 	if (rc2 != 0)
 		CERROR("rc2 %d\n", rc2);
 	LASSERT(rc2 == 0);
 
- out_0:
-	LIBCFS_FREE(info, infosz);
+ fail_ping_buffer_decref:
+	lnet_ping_buffer_decref(pbuf);
+	return rc;
+}
+
+static int
+lnet_discover(lnet_process_id_t id, __u32 force, lnet_process_id_t __user *ids,
+	      int n_ids)
+{
+	struct lnet_peer_ni *lpni;
+	struct lnet_peer_ni *p;
+	struct lnet_peer *lp;
+	lnet_process_id_t *buf;
+	int cpt;
+	int i;
+	int rc;
+	int max_intf = lnet_interfaces_max;
+
+	if (n_ids <= 0 ||
+	    id.nid == LNET_NID_ANY ||
+	    n_ids > max_intf)
+		return -EINVAL;
+
+	if (id.pid == LNET_PID_ANY)
+		id.pid = LNET_PID_LUSTRE;
+
+	LIBCFS_ALLOC(buf, n_ids * sizeof(*buf));
+	if (!buf)
+		return -ENOMEM;
+
+	cpt = lnet_net_lock_current();
+	lpni = lnet_nid2peerni_locked(id.nid, LNET_NID_ANY, cpt);
+	if (IS_ERR(lpni)) {
+		rc = PTR_ERR(lpni);
+		goto out;
+	}
+
+	/*
+	 * Clearing the NIDS_UPTODATE flag ensures the peer will
+	 * be discovered, provided discovery has not been disabled.
+	 */
+	lp = lpni->lpni_peer_net->lpn_peer;
+	spin_lock(&lp->lp_lock);
+	lp->lp_state &= ~LNET_PEER_NIDS_UPTODATE;
+	/* If the force flag is set, force a PING and PUSH as well. */
+	if (force)
+		lp->lp_state |= LNET_PEER_FORCE_PING | LNET_PEER_FORCE_PUSH;
+	spin_unlock(&lp->lp_lock);
+	rc = lnet_discover_peer_locked(lpni, cpt, true);
+	if (rc)
+		goto out_decref;
+
+	/* Peer may have changed. */
+	lp = lpni->lpni_peer_net->lpn_peer;
+	if (lp->lp_nnis < n_ids)
+		n_ids = lp->lp_nnis;
+
+	i = 0;
+	p = NULL;
+	while ((p = lnet_get_next_peer_ni_locked(lp, NULL, p)) != NULL) {
+		buf[i].pid = id.pid;
+		buf[i].nid = p->lpni_nid;
+		if (++i >= n_ids)
+			break;
+	}
+
+	lnet_net_unlock(cpt);
+
+	rc = -EFAULT;
+	if (copy_to_user(ids, buf, n_ids * sizeof(*buf)))
+		goto out_relock;
+	rc = n_ids;
+out_relock:
+	lnet_net_lock(cpt);
+out_decref:
+	lnet_peer_ni_decref_locked(lpni);
+out:
+	lnet_net_unlock(cpt);
+
 	return rc;
 }