IB/hfi1: Send MAD traps until repressed

A trap should be sent to the FM until the FM sends a repress message.
This is in line with the IBTA 13.4.9.

Add the ability to resend traps until a repress message is received.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Michael N. Henry <michael.n.henry@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hfi1/mad.c

@@ -59,6 +59,16 @@
 #define OPA_LINK_WIDTH_RESET_OLD 0x0fff
 #define OPA_LINK_WIDTH_RESET 0xffff
 
+struct trap_node {
+	struct list_head list;
+	struct opa_mad_notice_attr data;
+	__be64 tid;
+	int len;
+	u32 retry;
+	u8 in_use;
+	u8 repress;
+};
+
 static int smp_length_check(u32 data_size, u32 request_len)
 {
 	if (unlikely(request_len < data_size))
@@ -97,28 +107,156 @@ void hfi1_event_pkey_change(struct hfi1_devdata *dd, u8 port)
 	ib_dispatch_event(&event);
 }
 
-static void send_trap(struct hfi1_ibport *ibp, void *data, unsigned len)
+/*
+ * If the port is down, clean up all pending traps.  We need to be careful
+ * with the given trap, because it may be queued.
+ */
+static void cleanup_traps(struct hfi1_ibport *ibp, struct trap_node *trap)
+{
+	struct trap_node *node, *q;
+	unsigned long flags;
+	struct list_head trap_list;
+	int i;
+
+	for (i = 0; i < RVT_MAX_TRAP_LISTS; i++) {
+		spin_lock_irqsave(&ibp->rvp.lock, flags);
+		list_replace_init(&ibp->rvp.trap_lists[i].list, &trap_list);
+		ibp->rvp.trap_lists[i].list_len = 0;
+		spin_unlock_irqrestore(&ibp->rvp.lock, flags);
+
+		/*
+		 * Remove all items from the list, freeing all the non-given
+		 * traps.
+		 */
+		list_for_each_entry_safe(node, q, &trap_list, list) {
+			list_del(&node->list);
+			if (node != trap)
+				kfree(node);
+		}
+	}
+
+	/*
+	 * If this wasn't on one of the lists it would not be freed.  If it
+	 * was on the list, it is now safe to free.
+	 */
+	kfree(trap);
+}
+
+static struct trap_node *check_and_add_trap(struct hfi1_ibport *ibp,
+					    struct trap_node *trap)
+{
+	struct trap_node *node;
+	struct trap_list *trap_list;
+	unsigned long flags;
+	unsigned long timeout;
+	int found = 0;
+
+	/*
+	 * Since the retry (handle timeout) does not remove a trap request
+	 * from the list, all we have to do is compare the node.
+	 */
+	spin_lock_irqsave(&ibp->rvp.lock, flags);
+	trap_list = &ibp->rvp.trap_lists[trap->data.generic_type & 0x0F];
+
+	list_for_each_entry(node, &trap_list->list, list) {
+		if (node == trap) {
+			node->retry++;
+			found = 1;
+			break;
+		}
+	}
+
+	/* If it is not on the list, add it, limited to RVT-MAX_TRAP_LEN. */
+	if (!found) {
+		if (trap_list->list_len < RVT_MAX_TRAP_LEN) {
+			trap_list->list_len++;
+			list_add_tail(&trap->list, &trap_list->list);
+		} else {
+			pr_warn_ratelimited("hfi1: Maximim trap limit reached for 0x%0x traps\n",
+					    trap->data.generic_type);
+			kfree(trap);
+		}
+	}
+
+	/*
+	 * Next check to see if there is a timer pending.  If not, set it up
+	 * and get the first trap from the list.
+	 */
+	node = NULL;
+	if (!timer_pending(&ibp->rvp.trap_timer)) {
+		/*
+		 * o14-2
+		 * If the time out is set we have to wait until it expires
+		 * before the trap can be sent.
+		 * This should be > RVT_TRAP_TIMEOUT
+		 */
+		timeout = (RVT_TRAP_TIMEOUT *
+			   (1UL << ibp->rvp.subnet_timeout)) / 1000;
+		mod_timer(&ibp->rvp.trap_timer,
+			  jiffies + usecs_to_jiffies(timeout));
+		node = list_first_entry(&trap_list->list, struct trap_node,
+					list);
+		node->in_use = 1;
+	}
+	spin_unlock_irqrestore(&ibp->rvp.lock, flags);
+
+	return node;
+}
+
+static void subn_handle_opa_trap_repress(struct hfi1_ibport *ibp,
+					 struct opa_smp *smp)
+{
+	struct trap_list *trap_list;
+	struct trap_node *trap;
+	unsigned long flags;
+	int i;
+
+	if (smp->attr_id != IB_SMP_ATTR_NOTICE)
+		return;
+
+	spin_lock_irqsave(&ibp->rvp.lock, flags);
+	for (i = 0; i < RVT_MAX_TRAP_LISTS; i++) {
+		trap_list = &ibp->rvp.trap_lists[i];
+		trap = list_first_entry_or_null(&trap_list->list,
+						struct trap_node, list);
+		if (trap && trap->tid == smp->tid) {
+			if (trap->in_use) {
+				trap->repress = 1;
+			} else {
+				trap_list->list_len--;
+				list_del(&trap->list);
+				kfree(trap);
+			}
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&ibp->rvp.lock, flags);
+}
+
+static void send_trap(struct hfi1_ibport *ibp, struct trap_node *trap)
 {
 	struct ib_mad_send_buf *send_buf;
 	struct ib_mad_agent *agent;
 	struct opa_smp *smp;
-	int ret;
 	unsigned long flags;
-	unsigned long timeout;
 	int pkey_idx;
 	u32 qpn = ppd_from_ibp(ibp)->sm_trap_qp;
 
 	agent = ibp->rvp.send_agent;
-	if (!agent)
+	if (!agent) {
+		cleanup_traps(ibp, trap);
 		return;
+	}
 
 	/* o14-3.2.1 */
-	if (driver_lstate(ppd_from_ibp(ibp)) != IB_PORT_ACTIVE)
+	if (driver_lstate(ppd_from_ibp(ibp)) != IB_PORT_ACTIVE) {
+		cleanup_traps(ibp, trap);
 		return;
+	}
 
-	/* o14-2 */
-	if (ibp->rvp.trap_timeout && time_before(jiffies,
-						 ibp->rvp.trap_timeout))
+	/* Add the trap to the list if necessary and see if we can send it */
+	trap = check_and_add_trap(ibp, trap);
+	if (!trap)
 		return;
 
 	pkey_idx = hfi1_lookup_pkey_idx(ibp, LIM_MGMT_P_KEY);
@@ -139,11 +277,21 @@ static void send_trap(struct hfi1_ibport *ibp, void *data, unsigned len)
 	smp->mgmt_class = IB_MGMT_CLASS_SUBN_LID_ROUTED;
 	smp->class_version = OPA_SM_CLASS_VERSION;
 	smp->method = IB_MGMT_METHOD_TRAP;
-	ibp->rvp.tid++;
-	smp->tid = cpu_to_be64(ibp->rvp.tid);
+
+	/* Only update the transaction ID for new traps (o13-5). */
+	if (trap->tid == 0) {
+		ibp->rvp.tid++;
+		/* make sure that tid != 0 */
+		if (ibp->rvp.tid == 0)
+			ibp->rvp.tid++;
+		trap->tid = cpu_to_be64(ibp->rvp.tid);
+	}
+	smp->tid = trap->tid;
+
 	smp->attr_id = IB_SMP_ATTR_NOTICE;
 	/* o14-1: smp->mkey = 0; */
-	memcpy(smp->route.lid.data, data, len);
+
+	memcpy(smp->route.lid.data, &trap->data, trap->len);
 
 	spin_lock_irqsave(&ibp->rvp.lock, flags);
 	if (!ibp->rvp.sm_ah) {
@@ -152,31 +300,72 @@ static void send_trap(struct hfi1_ibport *ibp, void *data, unsigned len)
 
 			ah = hfi1_create_qp0_ah(ibp, ibp->rvp.sm_lid);
 			if (IS_ERR(ah)) {
-				ret = PTR_ERR(ah);
-			} else {
-				send_buf->ah = ah;
-				ibp->rvp.sm_ah = ibah_to_rvtah(ah);
-				ret = 0;
+				spin_unlock_irqrestore(&ibp->rvp.lock, flags);
+				return;
 			}
+			send_buf->ah = ah;
+			ibp->rvp.sm_ah = ibah_to_rvtah(ah);
 		} else {
-			ret = -EINVAL;
+			spin_unlock_irqrestore(&ibp->rvp.lock, flags);
+			return;
 		}
 	} else {
 		send_buf->ah = &ibp->rvp.sm_ah->ibah;
-		ret = 0;
 	}
+
+	/*
+	 * If the trap was repressed while things were getting set up, don't
+	 * bother sending it. This could happen for a retry.
+	 */
+	if (trap->repress) {
+		list_del(&trap->list);
+		spin_unlock_irqrestore(&ibp->rvp.lock, flags);
+		kfree(trap);
+		ib_free_send_mad(send_buf);
+		return;
+	}
+
+	trap->in_use = 0;
 	spin_unlock_irqrestore(&ibp->rvp.lock, flags);
 
-	if (!ret)
-		ret = ib_post_send_mad(send_buf, NULL);
-	if (!ret) {
-		/* 4.096 usec. */
-		timeout = (4096 * (1UL << ibp->rvp.subnet_timeout)) / 1000;
-		ibp->rvp.trap_timeout = jiffies + usecs_to_jiffies(timeout);
-	} else {
+	if (ib_post_send_mad(send_buf, NULL))
 		ib_free_send_mad(send_buf);
-		ibp->rvp.trap_timeout = 0;
+}
+
+void hfi1_handle_trap_timer(unsigned long data)
+{
+	struct hfi1_ibport *ibp = (struct hfi1_ibport *)data;
+	struct trap_node *trap = NULL;
+	unsigned long flags;
+	int i;
+
+	/* Find the trap with the highest priority */
+	spin_lock_irqsave(&ibp->rvp.lock, flags);
+	for (i = 0; !trap && i < RVT_MAX_TRAP_LISTS; i++) {
+		trap = list_first_entry_or_null(&ibp->rvp.trap_lists[i].list,
+						struct trap_node, list);
 	}
+	spin_unlock_irqrestore(&ibp->rvp.lock, flags);
+
+	if (trap)
+		send_trap(ibp, trap);
+}
+
+static struct trap_node *create_trap_node(u8 type, __be16 trap_num, u32 lid)
+{
+	struct trap_node *trap;
+
+	trap = kzalloc(sizeof(*trap), GFP_ATOMIC);
+	if (!trap)
+		return NULL;
+
+	INIT_LIST_HEAD(&trap->list);
+	trap->data.generic_type = type;
+	trap->data.prod_type_lsb = IB_NOTICE_PROD_CA;
+	trap->data.trap_num = trap_num;
+	trap->data.issuer_lid = cpu_to_be32(lid);
+
+	return trap;
 }
 
 /*
@@ -185,28 +374,29 @@ static void send_trap(struct hfi1_ibport *ibp, void *data, unsigned len)
 void hfi1_bad_pkey(struct hfi1_ibport *ibp, u32 key, u32 sl,
 		   u32 qp1, u32 qp2, u16 lid1, u16 lid2)
 {
-	struct opa_mad_notice_attr data;
+	struct trap_node *trap;
 	u32 lid = ppd_from_ibp(ibp)->lid;
 	u32 _lid1 = lid1;
 	u32 _lid2 = lid2;
 
-	memset(&data, 0, sizeof(data));
 	ibp->rvp.n_pkt_drops++;
 	ibp->rvp.pkey_violations++;
 
+	trap = create_trap_node(IB_NOTICE_TYPE_SECURITY, OPA_TRAP_BAD_P_KEY,
+				lid);
+	if (!trap)
+		return;
+
 	/* Send violation trap */
-	data.generic_type = IB_NOTICE_TYPE_SECURITY;
-	data.prod_type_lsb = IB_NOTICE_PROD_CA;
-	data.trap_num = OPA_TRAP_BAD_P_KEY;
-	data.issuer_lid = cpu_to_be32(lid);
-	data.ntc_257_258.lid1 = cpu_to_be32(_lid1);
-	data.ntc_257_258.lid2 = cpu_to_be32(_lid2);
-	data.ntc_257_258.key = cpu_to_be32(key);
-	data.ntc_257_258.sl = sl << 3;
-	data.ntc_257_258.qp1 = cpu_to_be32(qp1);
-	data.ntc_257_258.qp2 = cpu_to_be32(qp2);
-
-	send_trap(ibp, &data, sizeof(data));
+	trap->data.ntc_257_258.lid1 = cpu_to_be32(_lid1);
+	trap->data.ntc_257_258.lid2 = cpu_to_be32(_lid2);
+	trap->data.ntc_257_258.key = cpu_to_be32(key);
+	trap->data.ntc_257_258.sl = sl << 3;
+	trap->data.ntc_257_258.qp1 = cpu_to_be32(qp1);
+	trap->data.ntc_257_258.qp2 = cpu_to_be32(qp2);
+
+	trap->len = sizeof(trap->data);
+	send_trap(ibp, trap);
 }
 
 /*
@@ -215,34 +405,36 @@ void hfi1_bad_pkey(struct hfi1_ibport *ibp, u32 key, u32 sl,
 static void bad_mkey(struct hfi1_ibport *ibp, struct ib_mad_hdr *mad,
 		     __be64 mkey, __be32 dr_slid, u8 return_path[], u8 hop_cnt)
 {
-	struct opa_mad_notice_attr data;
+	struct trap_node *trap;
 	u32 lid = ppd_from_ibp(ibp)->lid;
 
-	memset(&data, 0, sizeof(data));
+	trap = create_trap_node(IB_NOTICE_TYPE_SECURITY, OPA_TRAP_BAD_M_KEY,
+				lid);
+	if (!trap)
+		return;
+
 	/* Send violation trap */
-	data.generic_type = IB_NOTICE_TYPE_SECURITY;
-	data.prod_type_lsb = IB_NOTICE_PROD_CA;
-	data.trap_num = OPA_TRAP_BAD_M_KEY;
-	data.issuer_lid = cpu_to_be32(lid);
-	data.ntc_256.lid = data.issuer_lid;
-	data.ntc_256.method = mad->method;
-	data.ntc_256.attr_id = mad->attr_id;
-	data.ntc_256.attr_mod = mad->attr_mod;
-	data.ntc_256.mkey = mkey;
+	trap->data.ntc_256.lid = trap->data.issuer_lid;
+	trap->data.ntc_256.method = mad->method;
+	trap->data.ntc_256.attr_id = mad->attr_id;
+	trap->data.ntc_256.attr_mod = mad->attr_mod;
+	trap->data.ntc_256.mkey = mkey;
 	if (mad->mgmt_class == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) {
-		data.ntc_256.dr_slid = dr_slid;
-		data.ntc_256.dr_trunc_hop = IB_NOTICE_TRAP_DR_NOTICE;
-		if (hop_cnt > ARRAY_SIZE(data.ntc_256.dr_rtn_path)) {
-			data.ntc_256.dr_trunc_hop |=
+		trap->data.ntc_256.dr_slid = dr_slid;
+		trap->data.ntc_256.dr_trunc_hop = IB_NOTICE_TRAP_DR_NOTICE;
+		if (hop_cnt > ARRAY_SIZE(trap->data.ntc_256.dr_rtn_path)) {
+			trap->data.ntc_256.dr_trunc_hop |=
 				IB_NOTICE_TRAP_DR_TRUNC;
-			hop_cnt = ARRAY_SIZE(data.ntc_256.dr_rtn_path);
+			hop_cnt = ARRAY_SIZE(trap->data.ntc_256.dr_rtn_path);
 		}
-		data.ntc_256.dr_trunc_hop |= hop_cnt;
-		memcpy(data.ntc_256.dr_rtn_path, return_path,
+		trap->data.ntc_256.dr_trunc_hop |= hop_cnt;
+		memcpy(trap->data.ntc_256.dr_rtn_path, return_path,
 		       hop_cnt);
 	}
 
-	send_trap(ibp, &data, sizeof(data));
+	trap->len = sizeof(trap->data);
+
+	send_trap(ibp, trap);
 }
 
 /*
@@ -250,23 +442,24 @@ static void bad_mkey(struct hfi1_ibport *ibp, struct ib_mad_hdr *mad,
  */
 void hfi1_cap_mask_chg(struct rvt_dev_info *rdi, u8 port_num)
 {
-	struct opa_mad_notice_attr data;
+	struct trap_node *trap;
 	struct hfi1_ibdev *verbs_dev = dev_from_rdi(rdi);
 	struct hfi1_devdata *dd = dd_from_dev(verbs_dev);
 	struct hfi1_ibport *ibp = &dd->pport[port_num - 1].ibport_data;
 	u32 lid = ppd_from_ibp(ibp)->lid;
 
-	memset(&data, 0, sizeof(data));
+	trap = create_trap_node(IB_NOTICE_TYPE_INFO,
+				OPA_TRAP_CHANGE_CAPABILITY,
+				lid);
+	if (!trap)
+		return;
 
-	data.generic_type = IB_NOTICE_TYPE_INFO;
-	data.prod_type_lsb = IB_NOTICE_PROD_CA;
-	data.trap_num = OPA_TRAP_CHANGE_CAPABILITY;
-	data.issuer_lid = cpu_to_be32(lid);
-	data.ntc_144.lid = data.issuer_lid;
-	data.ntc_144.new_cap_mask = cpu_to_be32(ibp->rvp.port_cap_flags);
-	data.ntc_144.cap_mask3 = cpu_to_be16(ibp->rvp.port_cap3_flags);
+	trap->data.ntc_144.lid = trap->data.issuer_lid;
+	trap->data.ntc_144.new_cap_mask = cpu_to_be32(ibp->rvp.port_cap_flags);
+	trap->data.ntc_144.cap_mask3 = cpu_to_be16(ibp->rvp.port_cap3_flags);
 
-	send_trap(ibp, &data, sizeof(data));
+	trap->len = sizeof(trap->data);
+	send_trap(ibp, trap);
 }
 
 /*
@@ -274,19 +467,19 @@ void hfi1_cap_mask_chg(struct rvt_dev_info *rdi, u8 port_num)
  */
 void hfi1_sys_guid_chg(struct hfi1_ibport *ibp)
 {
-	struct opa_mad_notice_attr data;
+	struct trap_node *trap;
 	u32 lid = ppd_from_ibp(ibp)->lid;
 
-	memset(&data, 0, sizeof(data));
+	trap = create_trap_node(IB_NOTICE_TYPE_INFO, OPA_TRAP_CHANGE_SYSGUID,
+				lid);
+	if (!trap)
+		return;
 
-	data.generic_type = IB_NOTICE_TYPE_INFO;
-	data.prod_type_lsb = IB_NOTICE_PROD_CA;
-	data.trap_num = OPA_TRAP_CHANGE_SYSGUID;
-	data.issuer_lid = cpu_to_be32(lid);
-	data.ntc_145.new_sys_guid = ib_hfi1_sys_image_guid;
-	data.ntc_145.lid = data.issuer_lid;
+	trap->data.ntc_145.new_sys_guid = ib_hfi1_sys_image_guid;
+	trap->data.ntc_145.lid = trap->data.issuer_lid;
 
-	send_trap(ibp, &data, sizeof(data));
+	trap->len = sizeof(trap->data);
+	send_trap(ibp, trap);
 }
 
 /*
@@ -294,20 +487,21 @@ void hfi1_sys_guid_chg(struct hfi1_ibport *ibp)
  */
 void hfi1_node_desc_chg(struct hfi1_ibport *ibp)
 {
-	struct opa_mad_notice_attr data;
+	struct trap_node *trap;
 	u32 lid = ppd_from_ibp(ibp)->lid;
 
-	memset(&data, 0, sizeof(data));
+	trap = create_trap_node(IB_NOTICE_TYPE_INFO,
+				OPA_TRAP_CHANGE_CAPABILITY,
+				lid);
+	if (!trap)
+		return;
 
-	data.generic_type = IB_NOTICE_TYPE_INFO;
-	data.prod_type_lsb = IB_NOTICE_PROD_CA;
-	data.trap_num = OPA_TRAP_CHANGE_CAPABILITY;
-	data.issuer_lid = cpu_to_be32(lid);
-	data.ntc_144.lid = data.issuer_lid;
-	data.ntc_144.change_flags =
+	trap->data.ntc_144.lid = trap->data.issuer_lid;
+	trap->data.ntc_144.change_flags =
 		cpu_to_be16(OPA_NOTICE_TRAP_NODE_DESC_CHG);
 
-	send_trap(ibp, &data, sizeof(data));
+	trap->len = sizeof(trap->data);
+	send_trap(ibp, trap);
 }
 
 static int __subn_get_opa_nodedesc(struct opa_smp *smp, u32 am,
@@ -4144,6 +4338,11 @@ static int process_subn_opa(struct ib_device *ibdev, int mad_flags,
 		 */
 		ret = IB_MAD_RESULT_SUCCESS;
 		break;
+	case IB_MGMT_METHOD_TRAP_REPRESS:
+		subn_handle_opa_trap_repress(ibp, smp);
+		/* Always successful */
+		ret = IB_MAD_RESULT_SUCCESS;
+		break;
 	default:
 		smp->status |= IB_SMP_UNSUP_METHOD;
 		ret = reply((struct ib_mad_hdr *)smp);

drivers/infiniband/hw/hfi1/mad.h

 /*
- * Copyright(c) 2015, 2016 Intel Corporation.
+ * Copyright(c) 2015 - 2017 Intel Corporation.
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
@@ -428,5 +428,6 @@ struct sc2vlnt {
 		    COUNTER_MASK(1, 4))
 
 void hfi1_event_pkey_change(struct hfi1_devdata *dd, u8 port);
+void hfi1_handle_trap_timer(unsigned long data);
 
 #endif				/* _HFI1_MAD_H */

drivers/infiniband/hw/hfi1/verbs.c

@@ -1535,6 +1535,11 @@ static void init_ibport(struct hfi1_pportdata *ppd)
 		ibp->sc_to_sl[i] = i;
 	}
 
+	for (i = 0; i < RVT_MAX_TRAP_LISTS ; i++)
+		INIT_LIST_HEAD(&ibp->rvp.trap_lists[i].list);
+	setup_timer(&ibp->rvp.trap_timer, hfi1_handle_trap_timer,
+		    (unsigned long)ibp);
+
 	spin_lock_init(&ibp->rvp.lock);
 	/* Set the prefix to the default value (see ch. 4.1.1) */
 	ibp->rvp.gid_prefix = IB_DEFAULT_GID_PREFIX;

include/rdma/rdma_vt.h

@@ -57,11 +57,21 @@
 #include <linux/list.h>
 #include <linux/hash.h>
 #include <rdma/ib_verbs.h>
+#include <rdma/ib_mad.h>
 #include <rdma/rdmavt_mr.h>
 #include <rdma/rdmavt_qp.h>
 
 #define RVT_MAX_PKEY_VALUES 16
 
+#define RVT_MAX_TRAP_LEN 100 /* Limit pending trap list */
+#define RVT_MAX_TRAP_LISTS ((IB_NOTICE_TYPE_INFO & 0x0F) + 1)
+#define RVT_TRAP_TIMEOUT 4096 /* 4.096 usec */
+
+struct trap_list {
+	u32 list_len;
+	struct list_head list;
+};
+
 struct rvt_ibport {
 	struct rvt_qp __rcu *qp[2];
 	struct ib_mad_agent *send_agent;	/* agent for SMI (traps) */
@@ -128,6 +138,13 @@ struct rvt_ibport {
 	u16 *pkey_table;
 
 	struct rvt_ah *sm_ah;
+
+	/*
+	 * Keep a list of traps that have not been repressed.  They will be
+	 * resent based on trap_timer.
+	 */
+	struct trap_list trap_lists[RVT_MAX_TRAP_LISTS];
+	struct timer_list trap_timer;
 };
 
 #define RVT_CQN_MAX 16 /* maximum length of cq name */