net: sch: api: add extack support in tcf_block_get

This patch adds extack support for the function tcf_block_get which is
a common used function in the tc subsystem. Callers which are interested
in the receiving error can assign extack to get a more detailed
information why tcf_block_get failed.

Cc: David Ahern <[email protected]>
Acked-by: Jamal Hadi Salim <[email protected]>
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: Alexander Aring

include/net/pkt_cls.h

@@ -39,9 +39,11 @@ struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 				bool create);
 void tcf_chain_put(struct tcf_chain *chain);
 int tcf_block_get(struct tcf_block **p_block,
-		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q);
+		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		  struct netlink_ext_ack *extack);
 int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
-		      struct tcf_block_ext_info *ei);
+		      struct tcf_block_ext_info *ei,
+		      struct netlink_ext_ack *extack);
 void tcf_block_put(struct tcf_block *block);
 void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
 		       struct tcf_block_ext_info *ei);

net/sched/cls_api.c

@@ -281,20 +281,24 @@ static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 }
 
 int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
-		      struct tcf_block_ext_info *ei)
+		      struct tcf_block_ext_info *ei,
+		      struct netlink_ext_ack *extack)
 {
 	struct tcf_block *block = kzalloc(sizeof(*block), GFP_KERNEL);
 	struct tcf_chain *chain;
 	int err;
 
-	if (!block)
+	if (!block) {
+		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 		return -ENOMEM;
+	}
 	INIT_LIST_HEAD(&block->chain_list);
 	INIT_LIST_HEAD(&block->cb_list);
 
 	/* Create chain 0 by default, it has to be always present. */
 	chain = tcf_chain_create(block, 0);
 	if (!chain) {
+		NL_SET_ERR_MSG(extack, "Failed to create new tcf chain");
 		err = -ENOMEM;
 		goto err_chain_create;
 	}
@@ -321,15 +325,16 @@ static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
 }
 
 int tcf_block_get(struct tcf_block **p_block,
-		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q)
+		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		  struct netlink_ext_ack *extack)
 {
 	struct tcf_block_ext_info ei = {
 		.chain_head_change = tcf_chain_head_change_dflt,
 		.chain_head_change_priv = p_filter_chain,
 	};
 
 	WARN_ON(!p_filter_chain);
-	return tcf_block_get_ext(p_block, q, &ei);
+	return tcf_block_get_ext(p_block, q, &ei, extack);
 }
 EXPORT_SYMBOL(tcf_block_get);
 

net/sched/sch_atm.c

@@ -283,7 +283,8 @@ static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
 		goto err_out;
 	}
 
-	error = tcf_block_get(&flow->block, &flow->filter_list, sch);
+	error = tcf_block_get(&flow->block, &flow->filter_list, sch,
+			      extack);
 	if (error) {
 		kfree(flow);
 		goto err_out;
@@ -550,7 +551,8 @@ static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt,
 		p->link.q = &noop_qdisc;
 	pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
 
-	err = tcf_block_get(&p->link.block, &p->link.filter_list, sch);
+	err = tcf_block_get(&p->link.block, &p->link.filter_list, sch,
+			    extack);
 	if (err)
 		return err;
 

net/sched/sch_cbq.c

@@ -1160,7 +1160,7 @@ static int cbq_init(struct Qdisc *sch, struct nlattr *opt,
 	if (!q->link.R_tab)
 		return -EINVAL;
 
-	err = tcf_block_get(&q->link.block, &q->link.filter_list, sch);
+	err = tcf_block_get(&q->link.block, &q->link.filter_list, sch, extack);
 	if (err)
 		goto put_rtab;
 
@@ -1576,7 +1576,7 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
 	if (cl == NULL)
 		goto failure;
 
-	err = tcf_block_get(&cl->block, &cl->filter_list, sch);
+	err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack);
 	if (err) {
 		kfree(cl);
 		return err;

net/sched/sch_drr.c

@@ -417,7 +417,7 @@ static int drr_init_qdisc(struct Qdisc *sch, struct nlattr *opt,
 	struct drr_sched *q = qdisc_priv(sch);
 	int err;
 
-	err = tcf_block_get(&q->block, &q->filter_list, sch);
+	err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
 	if (err)
 		return err;
 	err = qdisc_class_hash_init(&q->clhash);

net/sched/sch_dsmark.c

@@ -348,7 +348,7 @@ static int dsmark_init(struct Qdisc *sch, struct nlattr *opt,
 	if (!opt)
 		goto errout;
 
-	err = tcf_block_get(&p->block, &p->filter_list, sch);
+	err = tcf_block_get(&p->block, &p->filter_list, sch, extack);
 	if (err)
 		return err;
 

net/sched/sch_fq_codel.c

@@ -484,7 +484,7 @@ static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt,
 			return err;
 	}
 
-	err = tcf_block_get(&q->block, &q->filter_list, sch);
+	err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
 	if (err)
 		return err;
 

net/sched/sch_hfsc.c

@@ -1034,7 +1034,7 @@ hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
 	if (cl == NULL)
 		return -ENOBUFS;
 
-	err = tcf_block_get(&cl->block, &cl->filter_list, sch);
+	err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack);
 	if (err) {
 		kfree(cl);
 		return err;
@@ -1409,7 +1409,7 @@ hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt,
 		return err;
 	q->eligible = RB_ROOT;
 
-	err = tcf_block_get(&q->root.block, &q->root.filter_list, sch);
+	err = tcf_block_get(&q->root.block, &q->root.filter_list, sch, extack);
 	if (err)
 		return err;
 

net/sched/sch_htb.c

@@ -1032,7 +1032,7 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt,
 	if (!opt)
 		return -EINVAL;
 
-	err = tcf_block_get(&q->block, &q->filter_list, sch);
+	err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
 	if (err)
 		return err;
 
@@ -1397,7 +1397,7 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
 		if (!cl)
 			goto failure;
 
-		err = tcf_block_get(&cl->block, &cl->filter_list, sch);
+		err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack);
 		if (err) {
 			kfree(cl);
 			goto failure;

net/sched/sch_ingress.c

@@ -78,7 +78,7 @@ static int ingress_init(struct Qdisc *sch, struct nlattr *opt,
 	q->block_info.chain_head_change = clsact_chain_head_change;
 	q->block_info.chain_head_change_priv = &q->miniqp;
 
-	err = tcf_block_get_ext(&q->block, sch, &q->block_info);
+	err = tcf_block_get_ext(&q->block, sch, &q->block_info, extack);
 	if (err)
 		return err;
 
@@ -186,7 +186,8 @@ static int clsact_init(struct Qdisc *sch, struct nlattr *opt,
 	q->ingress_block_info.chain_head_change = clsact_chain_head_change;
 	q->ingress_block_info.chain_head_change_priv = &q->miniqp_ingress;
 
-	err = tcf_block_get_ext(&q->ingress_block, sch, &q->ingress_block_info);
+	err = tcf_block_get_ext(&q->ingress_block, sch, &q->ingress_block_info,
+				extack);
 	if (err)
 		return err;
 
@@ -196,7 +197,8 @@ static int clsact_init(struct Qdisc *sch, struct nlattr *opt,
 	q->egress_block_info.chain_head_change = clsact_chain_head_change;
 	q->egress_block_info.chain_head_change_priv = &q->miniqp_egress;
 
-	err = tcf_block_get_ext(&q->egress_block, sch, &q->egress_block_info);
+	err = tcf_block_get_ext(&q->egress_block, sch, &q->egress_block_info,
+				extack);
 	if (err)
 		return err;