[TIPC] Initial merge

TIPC (Transparent Inter Process Communication) is a protocol designed for
intra cluster communication. For more information see
http://tipc.sourceforge.net

Signed-off-by: Per Liden <per.liden@nospam.ericsson.com>

1 files changed, 522 insertions, 0 deletions

diff --git a/net/tipc/subscr.c b/net/tipc/subscr.c
new file mode 100644
index 0000000..6f651a2
--- /dev/null
+++ b/net/tipc/subscr.c
@@ -0,0 +1,522 @@
+/*
+ * net/tipc/subscr.c: TIPC subscription service
+ * 
+ * Copyright (c) 2003-2005, Ericsson Research Canada
+ * Copyright (c) 2005, Wind River Systems
+ * Copyright (c) 2005-2006, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this 
+ * list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, 
+ * this list of conditions and the following disclaimer in the documentation 
+ * and/or other materials provided with the distribution.
+ * Neither the names of the copyright holders nor the names of its 
+ * contributors may be used to endorse or promote products derived from this 
+ * software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "dbg.h"
+#include "subscr.h"
+#include "name_table.h"
+#include "ref.h"
+
+/**
+ * struct subscriber - TIPC network topology subscriber
+ * @ref: object reference to subscriber object itself
+ * @lock: pointer to spinlock controlling access to subscriber object
+ * @subscriber_list: adjacent subscribers in top. server's list of subscribers
+ * @subscription_list: list of subscription objects for this subscriber
+ * @port_ref: object reference to port used to communicate with subscriber
+ * @swap: indicates if subscriber uses opposite endianness in its messages
+ */
+ 
+struct subscriber {
+	u32 ref;
+        spinlock_t *lock;
+	struct list_head subscriber_list;
+	struct list_head subscription_list;
+	u32 port_ref;
+	int swap;
+};
+
+/**
+ * struct top_srv - TIPC network topology subscription service
+ * @user_ref: TIPC userid of subscription service
+ * @setup_port: reference to TIPC port that handles subscription requests
+ * @subscription_count: number of active subscriptions (not subscribers!)
+ * @subscriber_list: list of ports subscribing to service
+ * @lock: spinlock govering access to subscriber list
+ */
+
+struct top_srv {
+	u32 user_ref;
+	u32 setup_port;
+	atomic_t subscription_count;
+	struct list_head subscriber_list;
+	spinlock_t lock;
+};
+
+static struct top_srv topsrv = { 0 };
+
+/**
+ * htohl - convert value to endianness used by destination
+ * @in: value to convert
+ * @swap: non-zero if endianness must be reversed
+ * 
+ * Returns converted value
+ */
+
+static inline u32 htohl(u32 in, int swap)
+{
+	char *c = (char *)∈
+
+	return swap ? ((c[3] << 3) + (c[2] << 2) + (c[1] << 1) + c[0]) : in;
+}
+
+/**
+ * subscr_send_event - send a message containing a tipc_event to the subscriber
+ */
+
+static void subscr_send_event(struct subscription *sub, 
+			      u32 found_lower, 
+			      u32 found_upper,
+			      u32 event, 
+			      u32 port_ref, 
+			      u32 node)
+{
+	struct iovec msg_sect;
+
+	msg_sect.iov_base = (void *)&sub->evt;
+	msg_sect.iov_len = sizeof(struct tipc_event);
+
+	sub->evt.event = htohl(event, sub->owner->swap);
+	sub->evt.found_lower = htohl(found_lower, sub->owner->swap);
+	sub->evt.found_upper = htohl(found_upper, sub->owner->swap);
+	sub->evt.port.ref = htohl(port_ref, sub->owner->swap);
+	sub->evt.port.node = htohl(node, sub->owner->swap);
+	tipc_send(sub->owner->port_ref, 1, &msg_sect);
+}
+
+/**
+ * subscr_overlap - test for subscription overlap with the given values
+ *
+ * Returns 1 if there is overlap, otherwise 0.
+ */
+
+int subscr_overlap(struct subscription *sub, 
+		   u32 found_lower, 
+		   u32 found_upper)
+
+{
+	if (found_lower < sub->seq.lower)
+		found_lower = sub->seq.lower;
+	if (found_upper > sub->seq.upper)
+		found_upper = sub->seq.upper;
+	if (found_lower > found_upper)
+		return 0;
+	return 1;
+}
+
+/**
+ * subscr_report_overlap - issue event if there is subscription overlap
+ * 
+ * Protected by nameseq.lock in name_table.c
+ */
+
+void subscr_report_overlap(struct subscription *sub, 
+			   u32 found_lower, 
+			   u32 found_upper,
+			   u32 event, 
+			   u32 port_ref, 
+			   u32 node,
+			   int must)
+{
+	dbg("Rep overlap %u:%u,%u<->%u,%u\n", sub->seq.type, sub->seq.lower,
+	    sub->seq.upper, found_lower, found_upper);
+	if (!subscr_overlap(sub, found_lower, found_upper))
+		return;
+	if (!must && (sub->filter != TIPC_SUB_PORTS))
+		return;
+	subscr_send_event(sub, found_lower, found_upper, event, port_ref, node);
+}
+
+/**
+ * subscr_timeout - subscription timeout has occurred
+ */
+
+static void subscr_timeout(struct subscription *sub)
+{
+	struct subscriber *subscriber;
+	u32 subscriber_ref;
+
+	/* Validate subscriber reference (in case subscriber is terminating) */
+
+	subscriber_ref = sub->owner->ref;
+	subscriber = (struct subscriber *)ref_lock(subscriber_ref);
+	if (subscriber == NULL)
+		return;
+
+	/* Unlink subscription from name table */
+
+	nametbl_unsubscribe(sub);
+
+	/* Notify subscriber of timeout, then unlink subscription */
+
+	subscr_send_event(sub, 
+			  sub->evt.s.seq.lower, 
+			  sub->evt.s.seq.upper,
+			  TIPC_SUBSCR_TIMEOUT, 
+			  0, 
+			  0);
+	list_del(&sub->subscription_list);
+
+	/* Now destroy subscription */
+
+	ref_unlock(subscriber_ref);
+	k_term_timer(&sub->timer);
+	kfree(sub);
+	atomic_dec(&topsrv.subscription_count);
+}
+
+/**
+ * subscr_terminate - terminate communication with a subscriber
+ * 
+ * Called with subscriber locked.  Routine must temporarily release this lock
+ * to enable subscription timeout routine(s) to finish without deadlocking; 
+ * the lock is then reclaimed to allow caller to release it upon return.
+ * (This should work even in the unlikely event some other thread creates 
+ * a new object reference in the interim that uses this lock; this routine will
+ * simply wait for it to be released, then claim it.)
+ */
+
+static void subscr_terminate(struct subscriber *subscriber)
+{
+	struct subscription *sub;
+	struct subscription *sub_temp;
+
+	/* Invalidate subscriber reference */
+
+	ref_discard(subscriber->ref);
+	spin_unlock_bh(subscriber->lock);
+
+	/* Destroy any existing subscriptions for subscriber */
+	
+	list_for_each_entry_safe(sub, sub_temp, &subscriber->subscription_list,
+				 subscription_list) {
+		if (sub->timeout != TIPC_WAIT_FOREVER) {
+			k_cancel_timer(&sub->timer);
+			k_term_timer(&sub->timer);
+		}
+		nametbl_unsubscribe(sub);
+		list_del(&sub->subscription_list);
+		dbg("Term: Removed sub %u,%u,%u from subscriber %x list\n",
+		    sub->seq.type, sub->seq.lower, sub->seq.upper, subscriber);
+		kfree(sub);
+		atomic_dec(&topsrv.subscription_count);
+	}
+
+	/* Sever connection to subscriber */
+
+	tipc_shutdown(subscriber->port_ref);
+	tipc_deleteport(subscriber->port_ref);
+
+	/* Remove subscriber from topology server's subscriber list */
+
+	spin_lock_bh(&topsrv.lock);
+	list_del(&subscriber->subscriber_list);
+	spin_unlock_bh(&topsrv.lock);
+
+	/* Now destroy subscriber */
+
+	spin_lock_bh(subscriber->lock);
+	kfree(subscriber);
+}
+
+/**
+ * subscr_subscribe - create subscription for subscriber
+ * 
+ * Called with subscriber locked
+ */
+
+static void subscr_subscribe(struct tipc_subscr *s,
+			     struct subscriber *subscriber)
+{
+	struct subscription *sub;
+
+	/* Refuse subscription if global limit exceeded */
+
+	if (atomic_read(&topsrv.subscription_count) >= tipc_max_subscriptions) {
+		warn("Failed: max %u subscriptions\n", tipc_max_subscriptions);
+		subscr_terminate(subscriber);
+		return;
+	}
+
+	/* Allocate subscription object */
+
+	sub = kmalloc(sizeof(*sub), GFP_ATOMIC);
+	if (sub == NULL) {
+		warn("Memory squeeze; ignoring subscription\n");
+		subscr_terminate(subscriber);
+		return;
+	}
+
+	/* Determine/update subscriber's endianness */
+
+	if ((s->filter == TIPC_SUB_PORTS) || (s->filter == TIPC_SUB_SERVICE))
+		subscriber->swap = 0;
+	else
+		subscriber->swap = 1;
+
+	/* Initialize subscription object */
+
+	memset(sub, 0, sizeof(*sub));
+	sub->seq.type = htohl(s->seq.type, subscriber->swap);
+	sub->seq.lower = htohl(s->seq.lower, subscriber->swap);
+	sub->seq.upper = htohl(s->seq.upper, subscriber->swap);
+	sub->timeout = htohl(s->timeout, subscriber->swap);
+	sub->filter = htohl(s->filter, subscriber->swap);
+	if ((((sub->filter != TIPC_SUB_PORTS) 
+	      && (sub->filter != TIPC_SUB_SERVICE)))
+	    || (sub->seq.lower > sub->seq.upper)) {
+		warn("Rejecting illegal subscription %u,%u,%u\n",
+		     sub->seq.type, sub->seq.lower, sub->seq.upper);
+		kfree(sub);
+		subscr_terminate(subscriber);
+		return;
+	}
+	memcpy(&sub->evt.s, s, sizeof(struct tipc_subscr));
+	INIT_LIST_HEAD(&sub->subscription_list);
+	INIT_LIST_HEAD(&sub->nameseq_list);
+	list_add(&sub->subscription_list, &subscriber->subscription_list);
+	atomic_inc(&topsrv.subscription_count);
+	if (sub->timeout != TIPC_WAIT_FOREVER) {
+		k_init_timer(&sub->timer,
+			     (Handler)subscr_timeout, (unsigned long)sub);
+		k_start_timer(&sub->timer, sub->timeout);
+	}
+	sub->owner = subscriber;
+	nametbl_subscribe(sub);
+}
+
+/**
+ * subscr_conn_shutdown_event - handle termination request from subscriber
+ */
+
+static void subscr_conn_shutdown_event(void *usr_handle,
+				       u32 portref,
+				       struct sk_buff **buf,
+				       unsigned char const *data,
+				       unsigned int size,
+				       int reason)
+{
+	struct subscriber *subscriber = ref_lock((u32)usr_handle);
+	spinlock_t *subscriber_lock;
+
+	if (subscriber == NULL)
+		return;
+
+	subscriber_lock = subscriber->lock;
+	subscr_terminate(subscriber);
+	spin_unlock_bh(subscriber_lock);
+}
+
+/**
+ * subscr_conn_msg_event - handle new subscription request from subscriber
+ */
+
+static void subscr_conn_msg_event(void *usr_handle,
+				  u32 port_ref,
+				  struct sk_buff **buf,
+				  const unchar *data,
+				  u32 size)
+{
+	struct subscriber *subscriber = ref_lock((u32)usr_handle);
+	spinlock_t *subscriber_lock;
+
+	if (subscriber == NULL)
+		return;
+
+	subscriber_lock = subscriber->lock;
+	if (size != sizeof(struct tipc_subscr))
+		subscr_terminate(subscriber);
+	else
+		subscr_subscribe((struct tipc_subscr *)data, subscriber);
+	
+	spin_unlock_bh(subscriber_lock);
+}
+
+/**
+ * subscr_named_msg_event - handle request to establish a new subscriber
+ */
+
+static void subscr_named_msg_event(void *usr_handle,
+				   u32 port_ref,
+				   struct sk_buff **buf,
+				   const unchar *data,
+				   u32 size,
+				   u32 importance, 
+				   struct tipc_portid const *orig,
+				   struct tipc_name_seq const *dest)
+{
+	struct subscriber *subscriber;
+	struct iovec msg_sect = {0, 0};
+	spinlock_t *subscriber_lock;
+
+	dbg("subscr_named_msg_event: orig = %x own = %x,\n",
+	    orig->node, tipc_own_addr);
+	if (size && (size != sizeof(struct tipc_subscr))) {
+		warn("Received tipc_subscr of invalid size\n");
+		return;
+	}
+
+	/* Create subscriber object */
+
+	subscriber = kmalloc(sizeof(struct subscriber), GFP_ATOMIC);
+	if (subscriber == NULL) {
+		warn("Memory squeeze; ignoring subscriber setup\n");
+		return;
+	}
+	memset(subscriber, 0, sizeof(struct subscriber));
+	INIT_LIST_HEAD(&subscriber->subscription_list);
+	INIT_LIST_HEAD(&subscriber->subscriber_list);
+	subscriber->ref = ref_acquire(subscriber, &subscriber->lock);
+	if (subscriber->ref == 0) {
+		warn("Failed to acquire subscriber reference\n");
+		kfree(subscriber);
+		return;
+	}
+
+	/* Establish a connection to subscriber */
+
+	tipc_createport(topsrv.user_ref,
+			(void *)subscriber->ref,
+			importance,
+			0,
+			0,
+			subscr_conn_shutdown_event,
+			0,
+			0,
+			subscr_conn_msg_event,
+			0,
+			&subscriber->port_ref);
+	if (subscriber->port_ref == 0) {
+		warn("Memory squeeze; failed to create subscription port\n");
+		ref_discard(subscriber->ref);
+		kfree(subscriber);
+		return;
+	}
+	tipc_connect2port(subscriber->port_ref, orig);
+
+
+	/* Add subscriber to topology server's subscriber list */
+
+	ref_lock(subscriber->ref);
+	spin_lock_bh(&topsrv.lock);
+	list_add(&subscriber->subscriber_list, &topsrv.subscriber_list);
+	spin_unlock_bh(&topsrv.lock);
+
+	/*
+	 * Subscribe now if message contains a subscription,
+	 * otherwise send an empty response to complete connection handshaking
+	 */
+
+	subscriber_lock = subscriber->lock;
+	if (size)
+		subscr_subscribe((struct tipc_subscr *)data, subscriber);
+	else
+		tipc_send(subscriber->port_ref, 1, &msg_sect);
+
+	spin_unlock_bh(subscriber_lock);
+}
+
+int subscr_start(void)
+{
+	struct tipc_name_seq seq = {TIPC_TOP_SRV, TIPC_TOP_SRV, TIPC_TOP_SRV};
+	int res = -1;
+
+	memset(&topsrv, 0, sizeof (topsrv));
+	topsrv.lock = SPIN_LOCK_UNLOCKED;
+	INIT_LIST_HEAD(&topsrv.subscriber_list);
+
+	spin_lock_bh(&topsrv.lock);
+	res = tipc_attach(&topsrv.user_ref, 0, 0);
+	if (res) {
+		spin_unlock_bh(&topsrv.lock);
+		return res;
+	}
+
+ 	res = tipc_createport(topsrv.user_ref,
+ 			      0,
+ 			      TIPC_CRITICAL_IMPORTANCE,
+ 			      0,
+ 			      0,
+ 			      0,
+ 			      0,
+ 			      subscr_named_msg_event,
+ 			      0,
+ 			      0,
+ 			      &topsrv.setup_port);
+ 	if (res)
+		goto failed;
+
+ 	res = nametbl_publish_rsv(topsrv.setup_port, TIPC_NODE_SCOPE, &seq);
+ 	if (res)
+		goto failed;
+
+	spin_unlock_bh(&topsrv.lock);
+	return 0;
+
+failed:
+	err("Unable to create subscription service\n");
+	tipc_detach(topsrv.user_ref);
+	topsrv.user_ref = 0;
+	spin_unlock_bh(&topsrv.lock);
+	return res;
+}
+
+void subscr_stop(void)
+{
+	struct subscriber *subscriber;
+	struct subscriber *subscriber_temp;
+	spinlock_t *subscriber_lock;
+
+	if (topsrv.user_ref) {
+		tipc_deleteport(topsrv.setup_port);
+		list_for_each_entry_safe(subscriber, subscriber_temp, 
+					 &topsrv.subscriber_list,
+					 subscriber_list) {
+			ref_lock(subscriber->ref);
+			subscriber_lock = subscriber->lock;
+			subscr_terminate(subscriber);
+			spin_unlock_bh(subscriber_lock);
+		}
+		tipc_detach(topsrv.user_ref);
+		topsrv.user_ref = 0;
+	}
+}
+
+
+int tipc_ispublished(struct tipc_name const *name)
+{
+	u32 domain = 0;
+
+	return(nametbl_translate(name->type, name->instance,&domain) != 0);
+}
+