1 /* net/sched/sch_ingress.c - Ingress qdisc 2 * This program is free software; you can redistribute it and/or 3 * modify it under the terms of the GNU General Public License 4 * as published by the Free Software Foundation; either version 5 * 2 of the License, or (at your option) any later version. 6 * 7 * Authors: Jamal Hadi Salim 1999 8 */ 9 10 #include <linux/module.h> 11 #include <linux/types.h> 12 #include <linux/list.h> 13 #include <linux/skbuff.h> 14 #include <linux/rtnetlink.h> 15 #include <net/netlink.h> 16 #include <net/pkt_sched.h> 17 18 19 struct ingress_qdisc_data { 20 struct tcf_proto __rcu *filter_list; 21 }; 22 23 /* ------------------------- Class/flow operations ------------------------- */ 24 25 static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg) 26 { 27 return NULL; 28 } 29 30 static unsigned long ingress_get(struct Qdisc *sch, u32 classid) 31 { 32 return TC_H_MIN(classid) + 1; 33 } 34 35 static unsigned long ingress_bind_filter(struct Qdisc *sch, 36 unsigned long parent, u32 classid) 37 { 38 return ingress_get(sch, classid); 39 } 40 41 static void ingress_put(struct Qdisc *sch, unsigned long cl) 42 { 43 } 44 45 static void ingress_walk(struct Qdisc *sch, struct qdisc_walker *walker) 46 { 47 } 48 49 static struct tcf_proto __rcu **ingress_find_tcf(struct Qdisc *sch, 50 unsigned long cl) 51 { 52 struct ingress_qdisc_data *p = qdisc_priv(sch); 53 54 return &p->filter_list; 55 } 56 57 /* --------------------------- Qdisc operations ---------------------------- */ 58 59 static int ingress_enqueue(struct sk_buff *skb, struct Qdisc *sch) 60 { 61 struct ingress_qdisc_data *p = qdisc_priv(sch); 62 struct tcf_result res; 63 struct tcf_proto *fl = rcu_dereference_bh(p->filter_list); 64 int result; 65 66 result = tc_classify(skb, fl, &res); 67 68 qdisc_bstats_update(sch, skb); 69 switch (result) { 70 case TC_ACT_SHOT: 71 result = TC_ACT_SHOT; 72 qdisc_qstats_drop(sch); 73 break; 74 case TC_ACT_STOLEN: 75 case TC_ACT_QUEUED: 76 result = TC_ACT_STOLEN; 77 break; 78 case TC_ACT_RECLASSIFY: 79 case TC_ACT_OK: 80 skb->tc_index = TC_H_MIN(res.classid); 81 default: 82 result = TC_ACT_OK; 83 break; 84 } 85 86 return result; 87 } 88 89 /* ------------------------------------------------------------- */ 90 91 static int ingress_init(struct Qdisc *sch, struct nlattr *opt) 92 { 93 net_inc_ingress_queue(); 94 95 return 0; 96 } 97 98 static void ingress_destroy(struct Qdisc *sch) 99 { 100 struct ingress_qdisc_data *p = qdisc_priv(sch); 101 102 tcf_destroy_chain(&p->filter_list); 103 net_dec_ingress_queue(); 104 } 105 106 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb) 107 { 108 struct nlattr *nest; 109 110 nest = nla_nest_start(skb, TCA_OPTIONS); 111 if (nest == NULL) 112 goto nla_put_failure; 113 return nla_nest_end(skb, nest); 114 115 nla_put_failure: 116 nla_nest_cancel(skb, nest); 117 return -1; 118 } 119 120 static const struct Qdisc_class_ops ingress_class_ops = { 121 .leaf = ingress_leaf, 122 .get = ingress_get, 123 .put = ingress_put, 124 .walk = ingress_walk, 125 .tcf_chain = ingress_find_tcf, 126 .bind_tcf = ingress_bind_filter, 127 .unbind_tcf = ingress_put, 128 }; 129 130 static struct Qdisc_ops ingress_qdisc_ops __read_mostly = { 131 .cl_ops = &ingress_class_ops, 132 .id = "ingress", 133 .priv_size = sizeof(struct ingress_qdisc_data), 134 .enqueue = ingress_enqueue, 135 .init = ingress_init, 136 .destroy = ingress_destroy, 137 .dump = ingress_dump, 138 .owner = THIS_MODULE, 139 }; 140 141 static int __init ingress_module_init(void) 142 { 143 return register_qdisc(&ingress_qdisc_ops); 144 } 145 146 static void __exit ingress_module_exit(void) 147 { 148 unregister_qdisc(&ingress_qdisc_ops); 149 } 150 151 module_init(ingress_module_init) 152 module_exit(ingress_module_exit) 153 MODULE_LICENSE("GPL"); 154