// SPDX-License-Identifier: GPL-2.0-or-later

  /* net/sched/sch_ingress.c - Ingress and clsact qdisc
   *

   * Authors:     Jamal Hadi Salim 1999
   */

  #include <linux/module.h>
  #include <linux/types.h>

  #include <linux/list.h>

  #include <linux/skbuff.h>

  #include <linux/rtnetlink.h>

  #include <net/netlink.h>

  #include <net/pkt_sched.h>

  #include <net/pkt_cls.h>

  struct ingress_sched_data {
  	struct tcf_block *block;

  	struct tcf_block_ext_info block_info;

  	struct mini_Qdisc_pair miniqp;

  };

  static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg)
  {
  	return NULL;
  }

  static unsigned long ingress_find(struct Qdisc *sch, u32 classid)

  {

  	return TC_H_MIN(classid) + 1;
  }

  static unsigned long ingress_bind_filter(struct Qdisc *sch,

  					 unsigned long parent, u32 classid)

  {

  	return ingress_find(sch, classid);

  }

  static void ingress_unbind_filter(struct Qdisc *sch, unsigned long cl)

  {
  }

  static void ingress_walk(struct Qdisc *sch, struct qdisc_walker *walker)

  {

  }

  static struct tcf_block *ingress_tcf_block(struct Qdisc *sch, unsigned long cl,
  					   struct netlink_ext_ack *extack)

  {

  	struct ingress_sched_data *q = qdisc_priv(sch);

  	return q->block;

  }

  static void clsact_chain_head_change(struct tcf_proto *tp_head, void *priv)
  {

  	struct mini_Qdisc_pair *miniqp = priv;

  	mini_qdisc_pair_swap(miniqp, tp_head);

  };
  
  static void ingress_ingress_block_set(struct Qdisc *sch, u32 block_index)
  {
  	struct ingress_sched_data *q = qdisc_priv(sch);
  
  	q->block_info.block_index = block_index;
  }
  
  static u32 ingress_ingress_block_get(struct Qdisc *sch)
  {
  	struct ingress_sched_data *q = qdisc_priv(sch);
  
  	return q->block_info.block_index;

  }

  static int ingress_init(struct Qdisc *sch, struct nlattr *opt,
  			struct netlink_ext_ack *extack)

  {

  	struct ingress_sched_data *q = qdisc_priv(sch);
  	struct net_device *dev = qdisc_dev(sch);

  	int err;

  	net_inc_ingress_queue();

  	mini_qdisc_pair_init(&q->miniqp, sch, &dev->miniq_ingress);

  	q->block_info.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;

  	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, extack);
  	if (err)
  		return err;
  
  	mini_qdisc_pair_block_init(&q->miniqp, q->block);
  
  	return 0;

  }

  static void ingress_destroy(struct Qdisc *sch)
  {

  	struct ingress_sched_data *q = qdisc_priv(sch);

  	tcf_block_put_ext(q->block, sch, &q->block_info);

  	net_dec_ingress_queue();

  }

  static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
  {

  	struct nlattr *nest;

  	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);

  	if (nest == NULL)
  		goto nla_put_failure;

  	return nla_nest_end(skb, nest);

  nla_put_failure:

  	nla_nest_cancel(skb, nest);

  	return -1;
  }

  static const struct Qdisc_class_ops ingress_class_ops = {

  	.flags		=	QDISC_CLASS_OPS_DOIT_UNLOCKED,

  	.leaf		=	ingress_leaf,

  	.find		=	ingress_find,

  	.walk		=	ingress_walk,

  	.tcf_block	=	ingress_tcf_block,

  	.bind_tcf	=	ingress_bind_filter,

  	.unbind_tcf	=	ingress_unbind_filter,

  };

  static struct Qdisc_ops ingress_qdisc_ops __read_mostly = {

  	.cl_ops			=	&ingress_class_ops,
  	.id			=	"ingress",
  	.priv_size		=	sizeof(struct ingress_sched_data),
  	.static_flags		=	TCQ_F_CPUSTATS,
  	.init			=	ingress_init,
  	.destroy		=	ingress_destroy,
  	.dump			=	ingress_dump,
  	.ingress_block_set	=	ingress_ingress_block_set,
  	.ingress_block_get	=	ingress_ingress_block_get,
  	.owner			=	THIS_MODULE,

  };

  struct clsact_sched_data {
  	struct tcf_block *ingress_block;
  	struct tcf_block *egress_block;

  	struct tcf_block_ext_info ingress_block_info;
  	struct tcf_block_ext_info egress_block_info;

  	struct mini_Qdisc_pair miniqp_ingress;
  	struct mini_Qdisc_pair miniqp_egress;

  };

  static unsigned long clsact_find(struct Qdisc *sch, u32 classid)

  {
  	switch (TC_H_MIN(classid)) {
  	case TC_H_MIN(TC_H_MIN_INGRESS):
  	case TC_H_MIN(TC_H_MIN_EGRESS):
  		return TC_H_MIN(classid);
  	default:
  		return 0;
  	}
  }
  
  static unsigned long clsact_bind_filter(struct Qdisc *sch,
  					unsigned long parent, u32 classid)
  {

  	return clsact_find(sch, classid);

  }

  static struct tcf_block *clsact_tcf_block(struct Qdisc *sch, unsigned long cl,
  					  struct netlink_ext_ack *extack)

  {

  	struct clsact_sched_data *q = qdisc_priv(sch);

  
  	switch (cl) {
  	case TC_H_MIN(TC_H_MIN_INGRESS):

  		return q->ingress_block;

  	case TC_H_MIN(TC_H_MIN_EGRESS):

  		return q->egress_block;

  	default:
  		return NULL;
  	}
  }

  static void clsact_ingress_block_set(struct Qdisc *sch, u32 block_index)
  {
  	struct clsact_sched_data *q = qdisc_priv(sch);
  
  	q->ingress_block_info.block_index = block_index;
  }
  
  static void clsact_egress_block_set(struct Qdisc *sch, u32 block_index)
  {
  	struct clsact_sched_data *q = qdisc_priv(sch);
  
  	q->egress_block_info.block_index = block_index;
  }
  
  static u32 clsact_ingress_block_get(struct Qdisc *sch)
  {
  	struct clsact_sched_data *q = qdisc_priv(sch);
  
  	return q->ingress_block_info.block_index;
  }
  
  static u32 clsact_egress_block_get(struct Qdisc *sch)
  {
  	struct clsact_sched_data *q = qdisc_priv(sch);
  
  	return q->egress_block_info.block_index;
  }

  static int clsact_init(struct Qdisc *sch, struct nlattr *opt,
  		       struct netlink_ext_ack *extack)

  {

  	struct clsact_sched_data *q = qdisc_priv(sch);
  	struct net_device *dev = qdisc_dev(sch);
  	int err;

  	net_inc_ingress_queue();
  	net_inc_egress_queue();

  	mini_qdisc_pair_init(&q->miniqp_ingress, sch, &dev->miniq_ingress);

  	q->ingress_block_info.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;

  	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,
  				extack);

  	if (err)
  		return err;

  	mini_qdisc_pair_block_init(&q->miniqp_ingress, q->ingress_block);

  	mini_qdisc_pair_init(&q->miniqp_egress, sch, &dev->miniq_egress);

  	q->egress_block_info.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS;

  	q->egress_block_info.chain_head_change = clsact_chain_head_change;

  	q->egress_block_info.chain_head_change_priv = &q->miniqp_egress;

  	return tcf_block_get_ext(&q->egress_block, sch, &q->egress_block_info, extack);

  }
  
  static void clsact_destroy(struct Qdisc *sch)
  {

  	struct clsact_sched_data *q = qdisc_priv(sch);

  	tcf_block_put_ext(q->egress_block, sch, &q->egress_block_info);
  	tcf_block_put_ext(q->ingress_block, sch, &q->ingress_block_info);

  
  	net_dec_ingress_queue();
  	net_dec_egress_queue();
  }
  
  static const struct Qdisc_class_ops clsact_class_ops = {

  	.flags		=	QDISC_CLASS_OPS_DOIT_UNLOCKED,

  	.leaf		=	ingress_leaf,

  	.find		=	clsact_find,

  	.walk		=	ingress_walk,

  	.tcf_block	=	clsact_tcf_block,

  	.bind_tcf	=	clsact_bind_filter,

  	.unbind_tcf	=	ingress_unbind_filter,

  };
  
  static struct Qdisc_ops clsact_qdisc_ops __read_mostly = {

  	.cl_ops			=	&clsact_class_ops,
  	.id			=	"clsact",
  	.priv_size		=	sizeof(struct clsact_sched_data),
  	.static_flags		=	TCQ_F_CPUSTATS,
  	.init			=	clsact_init,
  	.destroy		=	clsact_destroy,
  	.dump			=	ingress_dump,
  	.ingress_block_set	=	clsact_ingress_block_set,
  	.egress_block_set	=	clsact_egress_block_set,
  	.ingress_block_get	=	clsact_ingress_block_get,
  	.egress_block_get	=	clsact_egress_block_get,
  	.owner			=	THIS_MODULE,

  };

  static int __init ingress_module_init(void)
  {

  	int ret;
  
  	ret = register_qdisc(&ingress_qdisc_ops);
  	if (!ret) {
  		ret = register_qdisc(&clsact_qdisc_ops);
  		if (ret)
  			unregister_qdisc(&ingress_qdisc_ops);
  	}
  
  	return ret;

  }

  static void __exit ingress_module_exit(void)

  {
  	unregister_qdisc(&ingress_qdisc_ops);

  	unregister_qdisc(&clsact_qdisc_ops);

  }

  module_init(ingress_module_init);
  module_exit(ingress_module_exit);

  MODULE_ALIAS("sch_clsact");

  MODULE_LICENSE("GPL");