xref: /openbmc/linux/net/sched/sch_ingress.c (revision a09d2831)
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	*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 	return;
48 }
49 
50 static struct tcf_proto **ingress_find_tcf(struct Qdisc *sch, 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 	int result;
64 
65 	result = tc_classify(skb, p->filter_list, &res);
66 
67 	sch->bstats.packets++;
68 	sch->bstats.bytes += qdisc_pkt_len(skb);
69 	switch (result) {
70 	case TC_ACT_SHOT:
71 		result = TC_ACT_SHOT;
72 		sch->qstats.drops++;
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 void ingress_destroy(struct Qdisc *sch)
92 {
93 	struct ingress_qdisc_data *p = qdisc_priv(sch);
94 
95 	tcf_destroy_chain(&p->filter_list);
96 }
97 
98 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
99 {
100 	struct nlattr *nest;
101 
102 	nest = nla_nest_start(skb, TCA_OPTIONS);
103 	if (nest == NULL)
104 		goto nla_put_failure;
105 	nla_nest_end(skb, nest);
106 	return skb->len;
107 
108 nla_put_failure:
109 	nla_nest_cancel(skb, nest);
110 	return -1;
111 }
112 
113 static const struct Qdisc_class_ops ingress_class_ops = {
114 	.leaf		=	ingress_leaf,
115 	.get		=	ingress_get,
116 	.put		=	ingress_put,
117 	.walk		=	ingress_walk,
118 	.tcf_chain	=	ingress_find_tcf,
119 	.bind_tcf	=	ingress_bind_filter,
120 	.unbind_tcf	=	ingress_put,
121 };
122 
123 static struct Qdisc_ops ingress_qdisc_ops __read_mostly = {
124 	.cl_ops		=	&ingress_class_ops,
125 	.id		=	"ingress",
126 	.priv_size	=	sizeof(struct ingress_qdisc_data),
127 	.enqueue	=	ingress_enqueue,
128 	.destroy	=	ingress_destroy,
129 	.dump		=	ingress_dump,
130 	.owner		=	THIS_MODULE,
131 };
132 
133 static int __init ingress_module_init(void)
134 {
135 	return register_qdisc(&ingress_qdisc_ops);
136 }
137 
138 static void __exit ingress_module_exit(void)
139 {
140 	unregister_qdisc(&ingress_qdisc_ops);
141 }
142 
143 module_init(ingress_module_init)
144 module_exit(ingress_module_exit)
145 MODULE_LICENSE("GPL");
146