xref: /openbmc/linux/net/sched/sch_ingress.c (revision 70342287)
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 }
48 
49 static struct tcf_proto **ingress_find_tcf(struct Qdisc *sch, unsigned long cl)
50 {
51 	struct ingress_qdisc_data *p = qdisc_priv(sch);
52 
53 	return &p->filter_list;
54 }
55 
56 /* --------------------------- Qdisc operations ---------------------------- */
57 
58 static int ingress_enqueue(struct sk_buff *skb, struct Qdisc *sch)
59 {
60 	struct ingress_qdisc_data *p = qdisc_priv(sch);
61 	struct tcf_result res;
62 	int result;
63 
64 	result = tc_classify(skb, p->filter_list, &res);
65 
66 	qdisc_bstats_update(sch, skb);
67 	switch (result) {
68 	case TC_ACT_SHOT:
69 		result = TC_ACT_SHOT;
70 		sch->qstats.drops++;
71 		break;
72 	case TC_ACT_STOLEN:
73 	case TC_ACT_QUEUED:
74 		result = TC_ACT_STOLEN;
75 		break;
76 	case TC_ACT_RECLASSIFY:
77 	case TC_ACT_OK:
78 		skb->tc_index = TC_H_MIN(res.classid);
79 	default:
80 		result = TC_ACT_OK;
81 		break;
82 	}
83 
84 	return result;
85 }
86 
87 /* ------------------------------------------------------------- */
88 
89 static void ingress_destroy(struct Qdisc *sch)
90 {
91 	struct ingress_qdisc_data *p = qdisc_priv(sch);
92 
93 	tcf_destroy_chain(&p->filter_list);
94 }
95 
96 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
97 {
98 	struct nlattr *nest;
99 
100 	nest = nla_nest_start(skb, TCA_OPTIONS);
101 	if (nest == NULL)
102 		goto nla_put_failure;
103 	nla_nest_end(skb, nest);
104 	return skb->len;
105 
106 nla_put_failure:
107 	nla_nest_cancel(skb, nest);
108 	return -1;
109 }
110 
111 static const struct Qdisc_class_ops ingress_class_ops = {
112 	.leaf		=	ingress_leaf,
113 	.get		=	ingress_get,
114 	.put		=	ingress_put,
115 	.walk		=	ingress_walk,
116 	.tcf_chain	=	ingress_find_tcf,
117 	.bind_tcf	=	ingress_bind_filter,
118 	.unbind_tcf	=	ingress_put,
119 };
120 
121 static struct Qdisc_ops ingress_qdisc_ops __read_mostly = {
122 	.cl_ops		=	&ingress_class_ops,
123 	.id		=	"ingress",
124 	.priv_size	=	sizeof(struct ingress_qdisc_data),
125 	.enqueue	=	ingress_enqueue,
126 	.destroy	=	ingress_destroy,
127 	.dump		=	ingress_dump,
128 	.owner		=	THIS_MODULE,
129 };
130 
131 static int __init ingress_module_init(void)
132 {
133 	return register_qdisc(&ingress_qdisc_ops);
134 }
135 
136 static void __exit ingress_module_exit(void)
137 {
138 	unregister_qdisc(&ingress_qdisc_ops);
139 }
140 
141 module_init(ingress_module_init)
142 module_exit(ingress_module_exit)
143 MODULE_LICENSE("GPL");
144