Commit 537ed567 authored by Horatiu Vultur's avatar Horatiu Vultur Committed by David S. Miller
Browse files

bridge: mrp: Implement the MRP Interconnect API 



Thie patch adds support for MRP Interconnect. Similar with the MRP ring,
if the HW can't generate MRP_InTest frames, then the SW will try to
generate them. And if also the SW fails to generate the frames then an
error is return to userspace.

The forwarding/termination of MRP_In frames is happening in the kernel
and is done by MRP instances.

Signed-off-by: default avatarHoratiu Vultur <horatiu.vultur@microchip.com>
Acked-by: default avatarNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f23f0db3

net/bridge/br_mrp.c

+539 −31
Original line number Diff line number Diff line
@@ -4,6 +4,27 @@ 
#include "br_private_mrp.h"



static const u8 mrp_test_dmac[ETH_ALEN] = { 0x1, 0x15, 0x4e, 0x0, 0x0, 0x1 };

static const u8 mrp_in_test_dmac[ETH_ALEN] = { 0x1, 0x15, 0x4e, 0x0, 0x0, 0x3 };



static bool br_mrp_is_ring_port(struct net_bridge_port *p_port,

				struct net_bridge_port *s_port,

				struct net_bridge_port *port)

{

	if (port == p_port ||

	    port == s_port)

		return true;



	return false;

}



static bool br_mrp_is_in_port(struct net_bridge_port *i_port,

			      struct net_bridge_port *port)

{

	if (port == i_port)

		return true;



	return false;

}



static struct net_bridge_port *br_mrp_get_port(struct net_bridge *br,

					       u32 ifindex)
@@ -37,6 +58,22 @@ static struct br_mrp *br_mrp_find_id(struct net_bridge *br, u32 ring_id) 
	return res;

}



static struct br_mrp *br_mrp_find_in_id(struct net_bridge *br, u32 in_id)

{

	struct br_mrp *res = NULL;

	struct br_mrp *mrp;



	list_for_each_entry_rcu(mrp, &br->mrp_list, list,

				lockdep_rtnl_is_held()) {

		if (mrp->in_id == in_id) {

			res = mrp;

			break;

		}

	}



	return res;

}



static bool br_mrp_unique_ifindex(struct net_bridge *br, u32 ifindex)

{

	struct br_mrp *mrp;
@@ -52,6 +89,10 @@ static bool br_mrp_unique_ifindex(struct net_bridge *br, u32 ifindex) 
		p = rtnl_dereference(mrp->s_port);

		if (p && p->dev->ifindex == ifindex)

			return false;



		p = rtnl_dereference(mrp->i_port);

		if (p && p->dev->ifindex == ifindex)

			return false;

	}



	return true;
@@ -66,7 +107,8 @@ static struct br_mrp *br_mrp_find_port(struct net_bridge *br, 
	list_for_each_entry_rcu(mrp, &br->mrp_list, list,

				lockdep_rtnl_is_held()) {

		if (rcu_access_pointer(mrp->p_port) == p ||

		    rcu_access_pointer(mrp->s_port) == p) {

		    rcu_access_pointer(mrp->s_port) == p ||

		    rcu_access_pointer(mrp->i_port) == p) {

			res = mrp;

			break;

		}
@@ -160,6 +202,36 @@ static struct sk_buff *br_mrp_alloc_test_skb(struct br_mrp *mrp, 
	return skb;

}



static struct sk_buff *br_mrp_alloc_in_test_skb(struct br_mrp *mrp,

						struct net_bridge_port *p,

						enum br_mrp_port_role_type port_role)

{

	struct br_mrp_in_test_hdr *hdr = NULL;

	struct sk_buff *skb = NULL;



	if (!p)

		return NULL;



	skb = br_mrp_skb_alloc(p, p->dev->dev_addr, mrp_in_test_dmac);

	if (!skb)

		return NULL;



	br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_IN_TEST, sizeof(*hdr));

	hdr = skb_put(skb, sizeof(*hdr));



	hdr->id = cpu_to_be16(mrp->in_id);

	ether_addr_copy(hdr->sa, p->br->dev->dev_addr);

	hdr->port_role = cpu_to_be16(port_role);

	hdr->state = cpu_to_be16(mrp->in_state);

	hdr->transitions = cpu_to_be16(mrp->in_transitions);

	hdr->timestamp = cpu_to_be32(jiffies_to_msecs(jiffies));



	br_mrp_skb_common(skb, mrp);

	br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_END, 0x0);



	return skb;

}



/* This function is continuously called in the following cases:

 * - when node role is MRM, in this case test_monitor is always set to false

 *   because it needs to notify the userspace that the ring is open and needs to
@@ -239,6 +311,83 @@ out: 
			   usecs_to_jiffies(mrp->test_interval));

}



/* This function is continuously called when the node has the interconnect role

 * MIM. It would generate interconnect test frames and will send them on all 3

 * ports. But will also check if it stop receiving interconnect test frames.

 */

static void br_mrp_in_test_work_expired(struct work_struct *work)

{

	struct delayed_work *del_work = to_delayed_work(work);

	struct br_mrp *mrp = container_of(del_work, struct br_mrp, in_test_work);

	struct net_bridge_port *p;

	bool notify_open = false;

	struct sk_buff *skb;



	if (time_before_eq(mrp->in_test_end, jiffies))

		return;



	if (mrp->in_test_count_miss < mrp->in_test_max_miss) {

		mrp->in_test_count_miss++;

	} else {

		/* Notify that the interconnect ring is open only if the

		 * interconnect ring state is closed, otherwise it would

		 * continue to notify at every interval.

		 */

		if (mrp->in_state == BR_MRP_IN_STATE_CLOSED)

			notify_open = true;

	}



	rcu_read_lock();



	p = rcu_dereference(mrp->p_port);

	if (p) {

		skb = br_mrp_alloc_in_test_skb(mrp, p,

					       BR_MRP_PORT_ROLE_PRIMARY);

		if (!skb)

			goto out;



		skb_reset_network_header(skb);

		dev_queue_xmit(skb);



		if (notify_open && !mrp->in_role_offloaded)

			br_mrp_in_port_open(p->dev, true);

	}



	p = rcu_dereference(mrp->s_port);

	if (p) {

		skb = br_mrp_alloc_in_test_skb(mrp, p,

					       BR_MRP_PORT_ROLE_SECONDARY);

		if (!skb)

			goto out;



		skb_reset_network_header(skb);

		dev_queue_xmit(skb);



		if (notify_open && !mrp->in_role_offloaded)

			br_mrp_in_port_open(p->dev, true);

	}



	p = rcu_dereference(mrp->i_port);

	if (p) {

		skb = br_mrp_alloc_in_test_skb(mrp, p,

					       BR_MRP_PORT_ROLE_INTER);

		if (!skb)

			goto out;



		skb_reset_network_header(skb);

		dev_queue_xmit(skb);



		if (notify_open && !mrp->in_role_offloaded)

			br_mrp_in_port_open(p->dev, true);

	}



out:

	rcu_read_unlock();



	queue_delayed_work(system_wq, &mrp->in_test_work,

			   usecs_to_jiffies(mrp->in_test_interval));

}



/* Deletes the MRP instance.

 * note: called under rtnl_lock

 */
@@ -251,6 +400,10 @@ static void br_mrp_del_impl(struct net_bridge *br, struct br_mrp *mrp) 
	cancel_delayed_work_sync(&mrp->test_work);

	br_mrp_switchdev_send_ring_test(br, mrp, 0, 0, 0, 0);



	/* Stop sending MRP_InTest frames if has an interconnect role */

	cancel_delayed_work_sync(&mrp->in_test_work);

	br_mrp_switchdev_send_in_test(br, mrp, 0, 0, 0);



	br_mrp_switchdev_del(br, mrp);



	/* Reset the ports */
@@ -278,6 +431,18 @@ static void br_mrp_del_impl(struct net_bridge *br, struct br_mrp *mrp) 
		rcu_assign_pointer(mrp->s_port, NULL);

	}



	p = rtnl_dereference(mrp->i_port);

	if (p) {

		spin_lock_bh(&br->lock);

		state = netif_running(br->dev) ?

				BR_STATE_FORWARDING : BR_STATE_DISABLED;

		p->state = state;

		p->flags &= ~BR_MRP_AWARE;

		spin_unlock_bh(&br->lock);

		br_mrp_port_switchdev_set_state(p, state);

		rcu_assign_pointer(mrp->i_port, NULL);

	}



	list_del_rcu(&mrp->list);

	kfree_rcu(mrp, rcu);

}
@@ -329,6 +494,7 @@ int br_mrp_add(struct net_bridge *br, struct br_mrp_instance *instance) 
	rcu_assign_pointer(mrp->s_port, p);



	INIT_DELAYED_WORK(&mrp->test_work, br_mrp_test_work_expired);

	INIT_DELAYED_WORK(&mrp->in_test_work, br_mrp_in_test_work_expired);

	list_add_tail_rcu(&mrp->list, &br->mrp_list);



	err = br_mrp_switchdev_add(br, mrp);
@@ -511,6 +677,180 @@ int br_mrp_start_test(struct net_bridge *br, 
	return 0;

}



/* Set in state, int state can be only Open or Closed

 * note: already called with rtnl_lock

 */

int br_mrp_set_in_state(struct net_bridge *br, struct br_mrp_in_state *state)

{

	struct br_mrp *mrp = br_mrp_find_in_id(br, state->in_id);



	if (!mrp)

		return -EINVAL;



	if (mrp->in_state == BR_MRP_IN_STATE_CLOSED &&

	    state->in_state != BR_MRP_IN_STATE_CLOSED)

		mrp->in_transitions++;



	mrp->in_state = state->in_state;



	br_mrp_switchdev_set_in_state(br, mrp, state->in_state);



	return 0;

}



/* Set in role, in role can be only MIM(Media Interconnection Manager) or

 * MIC(Media Interconnection Client).

 * note: already called with rtnl_lock

 */

int br_mrp_set_in_role(struct net_bridge *br, struct br_mrp_in_role *role)

{

	struct br_mrp *mrp = br_mrp_find_id(br, role->ring_id);

	struct net_bridge_port *p;

	int err;



	if (!mrp)

		return -EINVAL;



	if (!br_mrp_get_port(br, role->i_ifindex))

		return -EINVAL;



	if (role->in_role == BR_MRP_IN_ROLE_DISABLED) {

		u8 state;



		/* It is not allowed to disable a port that doesn't exist */

		p = rtnl_dereference(mrp->i_port);

		if (!p)

			return -EINVAL;



		/* Stop the generating MRP_InTest frames */

		cancel_delayed_work_sync(&mrp->in_test_work);

		br_mrp_switchdev_send_in_test(br, mrp, 0, 0, 0);



		/* Remove the port */

		spin_lock_bh(&br->lock);

		state = netif_running(br->dev) ?

				BR_STATE_FORWARDING : BR_STATE_DISABLED;

		p->state = state;

		p->flags &= ~BR_MRP_AWARE;

		spin_unlock_bh(&br->lock);

		br_mrp_port_switchdev_set_state(p, state);

		rcu_assign_pointer(mrp->i_port, NULL);



		mrp->in_role = role->in_role;

		mrp->in_id = 0;



		return 0;

	}



	/* It is not possible to have the same port part of multiple rings */

	if (!br_mrp_unique_ifindex(br, role->i_ifindex))

		return -EINVAL;



	/* It is not allowed to set a different interconnect port if the mrp

	 * instance has already one. First it needs to be disabled and after

	 * that set the new port

	 */

	if (rcu_access_pointer(mrp->i_port))

		return -EINVAL;



	p = br_mrp_get_port(br, role->i_ifindex);

	spin_lock_bh(&br->lock);

	p->state = BR_STATE_FORWARDING;

	p->flags |= BR_MRP_AWARE;

	spin_unlock_bh(&br->lock);

	rcu_assign_pointer(mrp->i_port, p);



	mrp->in_role = role->in_role;

	mrp->in_id = role->in_id;



	/* If there is an error just bailed out */

	err = br_mrp_switchdev_set_in_role(br, mrp, role->in_id,

					   role->ring_id, role->in_role);

	if (err && err != -EOPNOTSUPP)

		return err;



	/* Now detect if the HW actually applied the role or not. If the HW

	 * applied the role it means that the SW will not to do those operations

	 * anymore. For example if the role is MIM then the HW will notify the

	 * SW when interconnect ring is open, but if the is not pushed to the HW

	 * the SW will need to detect when the interconnect ring is open.

	 */

	mrp->in_role_offloaded = err == -EOPNOTSUPP ? 0 : 1;



	return 0;

}



/* Start to generate MRP_InTest frames, the frames are generated by

 * HW and if it fails, they are generated by the SW.

 * note: already called with rtnl_lock

 */

int br_mrp_start_in_test(struct net_bridge *br,

			 struct br_mrp_start_in_test *in_test)

{

	struct br_mrp *mrp = br_mrp_find_in_id(br, in_test->in_id);



	if (!mrp)

		return -EINVAL;



	if (mrp->in_role != BR_MRP_IN_ROLE_MIM)

		return -EINVAL;



	/* Try to push it to the HW and if it fails then continue with SW

	 * implementation and if that also fails then return error.

	 */

	if (!br_mrp_switchdev_send_in_test(br, mrp, in_test->interval,

					   in_test->max_miss, in_test->period))

		return 0;



	mrp->in_test_interval = in_test->interval;

	mrp->in_test_end = jiffies + usecs_to_jiffies(in_test->period);

	mrp->in_test_max_miss = in_test->max_miss;

	mrp->in_test_count_miss = 0;

	queue_delayed_work(system_wq, &mrp->in_test_work,

			   usecs_to_jiffies(in_test->interval));



	return 0;

}



/* Determin if the frame type is a ring frame */

static bool br_mrp_ring_frame(struct sk_buff *skb)

{

	const struct br_mrp_tlv_hdr *hdr;

	struct br_mrp_tlv_hdr _hdr;



	hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);

	if (!hdr)

		return false;



	if (hdr->type == BR_MRP_TLV_HEADER_RING_TEST ||

	    hdr->type == BR_MRP_TLV_HEADER_RING_TOPO ||

	    hdr->type == BR_MRP_TLV_HEADER_RING_LINK_DOWN ||

	    hdr->type == BR_MRP_TLV_HEADER_RING_LINK_UP ||

	    hdr->type == BR_MRP_TLV_HEADER_OPTION)

		return true;



	return false;

}



/* Determin if the frame type is an interconnect frame */

static bool br_mrp_in_frame(struct sk_buff *skb)

{

	const struct br_mrp_tlv_hdr *hdr;

	struct br_mrp_tlv_hdr _hdr;



	hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);

	if (!hdr)

		return false;



	if (hdr->type == BR_MRP_TLV_HEADER_IN_TEST ||

	    hdr->type == BR_MRP_TLV_HEADER_IN_TOPO ||

	    hdr->type == BR_MRP_TLV_HEADER_IN_LINK_DOWN ||

	    hdr->type == BR_MRP_TLV_HEADER_IN_LINK_UP)

		return true;



	return false;

}



/* Process only MRP Test frame. All the other MRP frames are processed by

 * userspace application

 * note: already called with rcu_read_lock
@@ -591,17 +931,92 @@ static void br_mrp_mra_process(struct br_mrp *mrp, struct net_bridge *br, 
		mrp->test_count_miss = 0;

}



/* This will just forward the frame to the other mrp ring port(MRC role) or will

 * not do anything.

/* Process only MRP InTest frame. All the other MRP frames are processed by

 * userspace application

 * note: already called with rcu_read_lock

 */

static bool br_mrp_mim_process(struct br_mrp *mrp, struct net_bridge_port *port,

			       struct sk_buff *skb)

{

	const struct br_mrp_in_test_hdr *in_hdr;

	struct br_mrp_in_test_hdr _in_hdr;

	const struct br_mrp_tlv_hdr *hdr;

	struct br_mrp_tlv_hdr _hdr;



	/* Each MRP header starts with a version field which is 16 bits.

	 * Therefore skip the version and get directly the TLV header.

	 */

	hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);

	if (!hdr)

		return false;



	/* The check for InTest frame type was already done */

	in_hdr = skb_header_pointer(skb, sizeof(uint16_t) + sizeof(_hdr),

				    sizeof(_in_hdr), &_in_hdr);

	if (!in_hdr)

		return false;



	/* It needs to process only it's own InTest frames. */

	if (mrp->in_id != ntohs(in_hdr->id))

		return false;



	mrp->in_test_count_miss = 0;



	/* Notify the userspace that the ring is closed only when the ring is

	 * not closed

	 */

	if (mrp->in_state != BR_MRP_IN_STATE_CLOSED)

		br_mrp_in_port_open(port->dev, false);



	return true;

}



/* Get the MRP frame type

 * note: already called with rcu_read_lock

 */

static u8 br_mrp_get_frame_type(struct sk_buff *skb)

{

	const struct br_mrp_tlv_hdr *hdr;

	struct br_mrp_tlv_hdr _hdr;



	/* Each MRP header starts with a version field which is 16 bits.

	 * Therefore skip the version and get directly the TLV header.

	 */

	hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr);

	if (!hdr)

		return 0xff;



	return hdr->type;

}



static bool br_mrp_mrm_behaviour(struct br_mrp *mrp)

{

	if (mrp->ring_role == BR_MRP_RING_ROLE_MRM ||

	    (mrp->ring_role == BR_MRP_RING_ROLE_MRA && !mrp->test_monitor))

		return true;



	return false;

}



static bool br_mrp_mrc_behaviour(struct br_mrp *mrp)

{

	if (mrp->ring_role == BR_MRP_RING_ROLE_MRC ||

	    (mrp->ring_role == BR_MRP_RING_ROLE_MRA && mrp->test_monitor))

		return true;



	return false;

}



/* This will just forward the frame to the other mrp ring ports, depending on

 * the frame type, ring role and interconnect role

 * note: already called with rcu_read_lock

 */

static int br_mrp_rcv(struct net_bridge_port *p,

		      struct sk_buff *skb, struct net_device *dev)

{

	struct net_device *s_dev, *p_dev, *d_dev;

	struct net_bridge_port *p_port, *s_port;

	struct net_bridge_port *p_port, *s_port, *i_port = NULL;

	struct net_bridge_port *p_dst, *s_dst, *i_dst = NULL;

	struct net_bridge *br;

	struct sk_buff *nskb;

	struct br_mrp *mrp;



	/* If port is disabled don't accept any frames */
@@ -616,46 +1031,139 @@ static int br_mrp_rcv(struct net_bridge_port *p, 
	p_port = rcu_dereference(mrp->p_port);

	if (!p_port)

		return 0;

	p_dst = p_port;



	s_port = rcu_dereference(mrp->s_port);

	if (!s_port)

		return 0;

	s_dst = s_port;



	/* If the frame is a ring frame then it is not required to check the

	 * interconnect role and ports to process or forward the frame

	 */

	if (br_mrp_ring_frame(skb)) {

		/* If the role is MRM then don't forward the frames */

		if (mrp->ring_role == BR_MRP_RING_ROLE_MRM) {

			br_mrp_mrm_process(mrp, p, skb);

		return 1;

			goto no_forward;

		}



	/* If the role is MRA then don't forward the frames if it behaves as

	 * MRM node

		/* If the role is MRA then don't forward the frames if it

		 * behaves as MRM node

		 */

		if (mrp->ring_role == BR_MRP_RING_ROLE_MRA) {

			if (!mrp->test_monitor) {

				br_mrp_mrm_process(mrp, p, skb);

			return 1;

				goto no_forward;

			}



			br_mrp_mra_process(mrp, br, p, skb);

		}



	/* Clone the frame and forward it on the other MRP port */

	nskb = skb_clone(skb, GFP_ATOMIC);

	if (!nskb)

		return 0;

		goto forward;

	}



	p_dev = p_port->dev;

	s_dev = s_port->dev;

	if (br_mrp_in_frame(skb)) {

		u8 in_type = br_mrp_get_frame_type(skb);



	if (p_dev == dev)

		d_dev = s_dev;

	else

		d_dev = p_dev;

		i_port = rcu_dereference(mrp->i_port);

		i_dst = i_port;



		/* If the ring port is in block state it should not forward

		 * In_Test frames

		 */

		if (br_mrp_is_ring_port(p_port, s_port, p) &&

		    p->state == BR_STATE_BLOCKING &&

		    in_type == BR_MRP_TLV_HEADER_IN_TEST)

			goto no_forward;



		/* Nodes that behaves as MRM needs to stop forwarding the

		 * frames in case the ring is closed, otherwise will be a loop.

		 * In this case the frame is no forward between the ring ports.

		 */

		if (br_mrp_mrm_behaviour(mrp) &&

		    br_mrp_is_ring_port(p_port, s_port, p) &&

		    (s_port->state != BR_STATE_FORWARDING ||

		     p_port->state != BR_STATE_FORWARDING)) {

			p_dst = NULL;

			s_dst = NULL;

		}



		/* A node that behaves as MRC and doesn't have a interconnect

		 * role then it should forward all frames between the ring ports

		 * because it doesn't have an interconnect port

		 */

		if (br_mrp_mrc_behaviour(mrp) &&

		    mrp->in_role == BR_MRP_IN_ROLE_DISABLED)

			goto forward;



		if (mrp->in_role == BR_MRP_IN_ROLE_MIM) {

			if (in_type == BR_MRP_TLV_HEADER_IN_TEST) {

				/* MIM should not forward it's own InTest

				 * frames

				 */

				if (br_mrp_mim_process(mrp, p, skb)) {

					goto no_forward;

				} else {

					if (br_mrp_is_ring_port(p_port, s_port,

								p))

						i_dst = NULL;



					if (br_mrp_is_in_port(i_port, p))

						goto no_forward;

				}

			} else {

				/* MIM should forward IntLinkChange and

				 * IntTopoChange between ring ports but MIM

				 * should not forward IntLinkChange and

				 * IntTopoChange if the frame was received at

				 * the interconnect port

				 */

				if (br_mrp_is_ring_port(p_port, s_port, p))

					i_dst = NULL;



				if (br_mrp_is_in_port(i_port, p))

					goto no_forward;

			}

		}



		if (mrp->in_role == BR_MRP_IN_ROLE_MIC) {

			/* MIC should forward InTest frames on all ports

			 * regardless of the received port

			 */

			if (in_type == BR_MRP_TLV_HEADER_IN_TEST)

				goto forward;



			/* MIC should forward IntLinkChange frames only if they

			 * are received on ring ports to all the ports

			 */

			if (br_mrp_is_ring_port(p_port, s_port, p) &&

			    (in_type == BR_MRP_TLV_HEADER_IN_LINK_UP ||

			     in_type == BR_MRP_TLV_HEADER_IN_LINK_DOWN))

				goto forward;



			/* Should forward the InTopo frames only between the

			 * ring ports

			 */

			if (in_type == BR_MRP_TLV_HEADER_IN_TOPO) {

				i_dst = NULL;

				goto forward;

			}



			/* In all the other cases don't forward the frames */

			goto no_forward;

		}

	}



	nskb->dev = d_dev;

	skb_push(nskb, ETH_HLEN);

	dev_queue_xmit(nskb);

forward:

	if (p_dst)

		br_forward(p_dst, skb, true, false);

	if (s_dst)

		br_forward(s_dst, skb, true, false);

	if (i_dst)

		br_forward(i_dst, skb, true, false);



no_forward:

	return 1;

}

net/bridge/br_private_mrp.h

+4 −0
Original line number Diff line number Diff line
@@ -57,6 +57,10 @@ int br_mrp_set_ring_state(struct net_bridge *br, 
			  struct br_mrp_ring_state *state);

int br_mrp_set_ring_role(struct net_bridge *br, struct br_mrp_ring_role *role);

int br_mrp_start_test(struct net_bridge *br, struct br_mrp_start_test *test);

int br_mrp_set_in_state(struct net_bridge *br, struct br_mrp_in_state *state);

int br_mrp_set_in_role(struct net_bridge *br, struct br_mrp_in_role *role);

int br_mrp_start_in_test(struct net_bridge *br,

			 struct br_mrp_start_in_test *test);



/* br_mrp_switchdev.c */

int br_mrp_switchdev_add(struct net_bridge *br, struct br_mrp *mrp);

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