Merge branch 'Fixes-for-SJA1105-DSA-tc-gate-action'

Vladimir Oltean says:

====================
Fixes for SJA1105 DSA tc-gate action

This small series fixes 2 bugs in the tc-gate implementation:
1. The TAS state machine keeps getting rescheduled even after removing
   tc-gate actions on all ports.
2. tc-gate actions with only one gate control list entry are installed
   to hardware with an incorrect interval of zero, which makes the
   switch erroneously drop those packets (since the configuration is
   invalid).

To keep the code palatable, a forward-declaration was avoided by moving
some code around in patch 1/4. I hope that isn't too much of an issue.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/sja1105/sja1105_vl.c

@@ -7,6 +7,165 @@
 
 #define SJA1105_SIZE_VL_STATUS			8
 
+/* Insert into the global gate list, sorted by gate action time. */
+static int sja1105_insert_gate_entry(struct sja1105_gating_config *gating_cfg,
+				     struct sja1105_rule *rule,
+				     u8 gate_state, s64 entry_time,
+				     struct netlink_ext_ack *extack)
+{
+	struct sja1105_gate_entry *e;
+	int rc;
+
+	e = kzalloc(sizeof(*e), GFP_KERNEL);
+	if (!e)
+		return -ENOMEM;
+
+	e->rule = rule;
+	e->gate_state = gate_state;
+	e->interval = entry_time;
+
+	if (list_empty(&gating_cfg->entries)) {
+		list_add(&e->list, &gating_cfg->entries);
+	} else {
+		struct sja1105_gate_entry *p;
+
+		list_for_each_entry(p, &gating_cfg->entries, list) {
+			if (p->interval == e->interval) {
+				NL_SET_ERR_MSG_MOD(extack,
+						   "Gate conflict");
+				rc = -EBUSY;
+				goto err;
+			}
+
+			if (e->interval < p->interval)
+				break;
+		}
+		list_add(&e->list, p->list.prev);
+	}
+
+	gating_cfg->num_entries++;
+
+	return 0;
+err:
+	kfree(e);
+	return rc;
+}
+
+/* The gate entries contain absolute times in their e->interval field. Convert
+ * that to proper intervals (i.e. "0, 5, 10, 15" to "5, 5, 5, 5").
+ */
+static void
+sja1105_gating_cfg_time_to_interval(struct sja1105_gating_config *gating_cfg,
+				    u64 cycle_time)
+{
+	struct sja1105_gate_entry *last_e;
+	struct sja1105_gate_entry *e;
+	struct list_head *prev;
+
+	list_for_each_entry(e, &gating_cfg->entries, list) {
+		struct sja1105_gate_entry *p;
+
+		prev = e->list.prev;
+
+		if (prev == &gating_cfg->entries)
+			continue;
+
+		p = list_entry(prev, struct sja1105_gate_entry, list);
+		p->interval = e->interval - p->interval;
+	}
+	last_e = list_last_entry(&gating_cfg->entries,
+				 struct sja1105_gate_entry, list);
+	last_e->interval = cycle_time - last_e->interval;
+}
+
+static void sja1105_free_gating_config(struct sja1105_gating_config *gating_cfg)
+{
+	struct sja1105_gate_entry *e, *n;
+
+	list_for_each_entry_safe(e, n, &gating_cfg->entries, list) {
+		list_del(&e->list);
+		kfree(e);
+	}
+}
+
+static int sja1105_compose_gating_subschedule(struct sja1105_private *priv,
+					      struct netlink_ext_ack *extack)
+{
+	struct sja1105_gating_config *gating_cfg = &priv->tas_data.gating_cfg;
+	struct sja1105_rule *rule;
+	s64 max_cycle_time = 0;
+	s64 its_base_time = 0;
+	int i, rc = 0;
+
+	sja1105_free_gating_config(gating_cfg);
+
+	list_for_each_entry(rule, &priv->flow_block.rules, list) {
+		if (rule->type != SJA1105_RULE_VL)
+			continue;
+		if (rule->vl.type != SJA1105_VL_TIME_TRIGGERED)
+			continue;
+
+		if (max_cycle_time < rule->vl.cycle_time) {
+			max_cycle_time = rule->vl.cycle_time;
+			its_base_time = rule->vl.base_time;
+		}
+	}
+
+	if (!max_cycle_time)
+		return 0;
+
+	dev_dbg(priv->ds->dev, "max_cycle_time %lld its_base_time %lld\n",
+		max_cycle_time, its_base_time);
+
+	gating_cfg->base_time = its_base_time;
+	gating_cfg->cycle_time = max_cycle_time;
+	gating_cfg->num_entries = 0;
+
+	list_for_each_entry(rule, &priv->flow_block.rules, list) {
+		s64 time;
+		s64 rbt;
+
+		if (rule->type != SJA1105_RULE_VL)
+			continue;
+		if (rule->vl.type != SJA1105_VL_TIME_TRIGGERED)
+			continue;
+
+		/* Calculate the difference between this gating schedule's
+		 * base time, and the base time of the gating schedule with the
+		 * longest cycle time. We call it the relative base time (rbt).
+		 */
+		rbt = future_base_time(rule->vl.base_time, rule->vl.cycle_time,
+				       its_base_time);
+		rbt -= its_base_time;
+
+		time = rbt;
+
+		for (i = 0; i < rule->vl.num_entries; i++) {
+			u8 gate_state = rule->vl.entries[i].gate_state;
+			s64 entry_time = time;
+
+			while (entry_time < max_cycle_time) {
+				rc = sja1105_insert_gate_entry(gating_cfg, rule,
+							       gate_state,
+							       entry_time,
+							       extack);
+				if (rc)
+					goto err;
+
+				entry_time += rule->vl.cycle_time;
+			}
+			time += rule->vl.entries[i].interval;
+		}
+	}
+
+	sja1105_gating_cfg_time_to_interval(gating_cfg, max_cycle_time);
+
+	return 0;
+err:
+	sja1105_free_gating_config(gating_cfg);
+	return rc;
+}
+
 /* The switch flow classification core implements TTEthernet, which 'thinks' in
  * terms of Virtual Links (VL), a concept borrowed from ARINC 664 part 7.
  * However it also has one other operating mode (VLLUPFORMAT=0) where it acts
@@ -390,171 +549,19 @@ int sja1105_vl_delete(struct sja1105_private *priv, int port,
 		kfree(rule);
 	}
 
-	rc = sja1105_init_virtual_links(priv, extack);
+	rc = sja1105_compose_gating_subschedule(priv, extack);
 	if (rc)
 		return rc;
 
-	return sja1105_static_config_reload(priv, SJA1105_VIRTUAL_LINKS);
-}
-
-/* Insert into the global gate list, sorted by gate action time. */
-static int sja1105_insert_gate_entry(struct sja1105_gating_config *gating_cfg,
-				     struct sja1105_rule *rule,
-				     u8 gate_state, s64 entry_time,
-				     struct netlink_ext_ack *extack)
-{
-	struct sja1105_gate_entry *e;
-	int rc;
-
-	e = kzalloc(sizeof(*e), GFP_KERNEL);
-	if (!e)
-		return -ENOMEM;
-
-	e->rule = rule;
-	e->gate_state = gate_state;
-	e->interval = entry_time;
-
-	if (list_empty(&gating_cfg->entries)) {
-		list_add(&e->list, &gating_cfg->entries);
-	} else {
-		struct sja1105_gate_entry *p;
-
-		list_for_each_entry(p, &gating_cfg->entries, list) {
-			if (p->interval == e->interval) {
-				NL_SET_ERR_MSG_MOD(extack,
-						   "Gate conflict");
-				rc = -EBUSY;
-				goto err;
-			}
-
-			if (e->interval < p->interval)
-				break;
-		}
-		list_add(&e->list, p->list.prev);
-	}
-
-	gating_cfg->num_entries++;
-
-	return 0;
-err:
-	kfree(e);
-	return rc;
-}
-
-/* The gate entries contain absolute times in their e->interval field. Convert
- * that to proper intervals (i.e. "0, 5, 10, 15" to "5, 5, 5, 5").
- */
-static void
-sja1105_gating_cfg_time_to_interval(struct sja1105_gating_config *gating_cfg,
-				    u64 cycle_time)
-{
-	struct sja1105_gate_entry *last_e;
-	struct sja1105_gate_entry *e;
-	struct list_head *prev;
-
-	list_for_each_entry(e, &gating_cfg->entries, list) {
-		struct sja1105_gate_entry *p;
-
-		prev = e->list.prev;
-
-		if (prev == &gating_cfg->entries)
-			continue;
-
-		p = list_entry(prev, struct sja1105_gate_entry, list);
-		p->interval = e->interval - p->interval;
-	}
-	last_e = list_last_entry(&gating_cfg->entries,
-				 struct sja1105_gate_entry, list);
-	if (last_e->list.prev != &gating_cfg->entries)
-		last_e->interval = cycle_time - last_e->interval;
-}
-
-static void sja1105_free_gating_config(struct sja1105_gating_config *gating_cfg)
-{
-	struct sja1105_gate_entry *e, *n;
-
-	list_for_each_entry_safe(e, n, &gating_cfg->entries, list) {
-		list_del(&e->list);
-		kfree(e);
-	}
-}
-
-static int sja1105_compose_gating_subschedule(struct sja1105_private *priv,
-					      struct netlink_ext_ack *extack)
-{
-	struct sja1105_gating_config *gating_cfg = &priv->tas_data.gating_cfg;
-	struct sja1105_rule *rule;
-	s64 max_cycle_time = 0;
-	s64 its_base_time = 0;
-	int i, rc = 0;
-
-	list_for_each_entry(rule, &priv->flow_block.rules, list) {
-		if (rule->type != SJA1105_RULE_VL)
-			continue;
-		if (rule->vl.type != SJA1105_VL_TIME_TRIGGERED)
-			continue;
-
-		if (max_cycle_time < rule->vl.cycle_time) {
-			max_cycle_time = rule->vl.cycle_time;
-			its_base_time = rule->vl.base_time;
-		}
-	}
-
-	if (!max_cycle_time)
-		return 0;
-
-	dev_dbg(priv->ds->dev, "max_cycle_time %lld its_base_time %lld\n",
-		max_cycle_time, its_base_time);
-
-	sja1105_free_gating_config(gating_cfg);
-
-	gating_cfg->base_time = its_base_time;
-	gating_cfg->cycle_time = max_cycle_time;
-	gating_cfg->num_entries = 0;
-
-	list_for_each_entry(rule, &priv->flow_block.rules, list) {
-		s64 time;
-		s64 rbt;
-
-		if (rule->type != SJA1105_RULE_VL)
-			continue;
-		if (rule->vl.type != SJA1105_VL_TIME_TRIGGERED)
-			continue;
-
-		/* Calculate the difference between this gating schedule's
-		 * base time, and the base time of the gating schedule with the
-		 * longest cycle time. We call it the relative base time (rbt).
-		 */
-		rbt = future_base_time(rule->vl.base_time, rule->vl.cycle_time,
-				       its_base_time);
-		rbt -= its_base_time;
-
-		time = rbt;
-
-		for (i = 0; i < rule->vl.num_entries; i++) {
-			u8 gate_state = rule->vl.entries[i].gate_state;
-			s64 entry_time = time;
-
-			while (entry_time < max_cycle_time) {
-				rc = sja1105_insert_gate_entry(gating_cfg, rule,
-							       gate_state,
-							       entry_time,
-							       extack);
-				if (rc)
-					goto err;
-
-				entry_time += rule->vl.cycle_time;
-			}
-			time += rule->vl.entries[i].interval;
-		}
-	}
+	rc = sja1105_init_virtual_links(priv, extack);
+	if (rc)
+		return rc;
 
-	sja1105_gating_cfg_time_to_interval(gating_cfg, max_cycle_time);
+	rc = sja1105_init_scheduling(priv);
+	if (rc < 0)
+		return rc;
 
-	return 0;
-err:
-	sja1105_free_gating_config(gating_cfg);
-	return rc;
+	return sja1105_static_config_reload(priv, SJA1105_VIRTUAL_LINKS);
 }
 
 int sja1105_vl_gate(struct sja1105_private *priv, int port,