xref: /openbmc/linux/net/sched/sch_ingress.c (revision 643d1f7f)
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 int ingress_graft(struct Qdisc *sch, unsigned long arg,
26 			 struct Qdisc *new, struct Qdisc **old)
27 {
28 	return -EOPNOTSUPP;
29 }
30 
31 static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg)
32 {
33 	return NULL;
34 }
35 
36 static unsigned long ingress_get(struct Qdisc *sch, u32 classid)
37 {
38 	return TC_H_MIN(classid) + 1;
39 }
40 
41 static unsigned long ingress_bind_filter(struct Qdisc *sch,
42 					 unsigned long parent, u32 classid)
43 {
44 	return ingress_get(sch, classid);
45 }
46 
47 static void ingress_put(struct Qdisc *sch, unsigned long cl)
48 {
49 }
50 
51 static int ingress_change(struct Qdisc *sch, u32 classid, u32 parent,
52 			  struct nlattr **tca, unsigned long *arg)
53 {
54 	return 0;
55 }
56 
57 static void ingress_walk(struct Qdisc *sch, struct qdisc_walker *walker)
58 {
59 	return;
60 }
61 
62 static struct tcf_proto **ingress_find_tcf(struct Qdisc *sch, unsigned long cl)
63 {
64 	struct ingress_qdisc_data *p = qdisc_priv(sch);
65 
66 	return &p->filter_list;
67 }
68 
69 /* --------------------------- Qdisc operations ---------------------------- */
70 
71 static int ingress_enqueue(struct sk_buff *skb, struct Qdisc *sch)
72 {
73 	struct ingress_qdisc_data *p = qdisc_priv(sch);
74 	struct tcf_result res;
75 	int result;
76 
77 	result = tc_classify(skb, p->filter_list, &res);
78 
79 	sch->bstats.packets++;
80 	sch->bstats.bytes += skb->len;
81 	switch (result) {
82 	case TC_ACT_SHOT:
83 		result = TC_ACT_SHOT;
84 		sch->qstats.drops++;
85 		break;
86 	case TC_ACT_STOLEN:
87 	case TC_ACT_QUEUED:
88 		result = TC_ACT_STOLEN;
89 		break;
90 	case TC_ACT_RECLASSIFY:
91 	case TC_ACT_OK:
92 		skb->tc_index = TC_H_MIN(res.classid);
93 	default:
94 		result = TC_ACT_OK;
95 		break;
96 	}
97 
98 	return result;
99 }
100 
101 /* ------------------------------------------------------------- */
102 
103 static void ingress_destroy(struct Qdisc *sch)
104 {
105 	struct ingress_qdisc_data *p = qdisc_priv(sch);
106 
107 	tcf_destroy_chain(p->filter_list);
108 }
109 
110 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
111 {
112 	struct nlattr *nest;
113 
114 	nest = nla_nest_start(skb, TCA_OPTIONS);
115 	if (nest == NULL)
116 		goto nla_put_failure;
117 	nla_nest_end(skb, nest);
118 	return skb->len;
119 
120 nla_put_failure:
121 	nla_nest_cancel(skb, nest);
122 	return -1;
123 }
124 
125 static const struct Qdisc_class_ops ingress_class_ops = {
126 	.graft		=	ingress_graft,
127 	.leaf		=	ingress_leaf,
128 	.get		=	ingress_get,
129 	.put		=	ingress_put,
130 	.change		=	ingress_change,
131 	.walk		=	ingress_walk,
132 	.tcf_chain	=	ingress_find_tcf,
133 	.bind_tcf	=	ingress_bind_filter,
134 	.unbind_tcf	=	ingress_put,
135 };
136 
137 static struct Qdisc_ops ingress_qdisc_ops __read_mostly = {
138 	.cl_ops		=	&ingress_class_ops,
139 	.id		=	"ingress",
140 	.priv_size	=	sizeof(struct ingress_qdisc_data),
141 	.enqueue	=	ingress_enqueue,
142 	.destroy	=	ingress_destroy,
143 	.dump		=	ingress_dump,
144 	.owner		=	THIS_MODULE,
145 };
146 
147 static int __init ingress_module_init(void)
148 {
149 	return register_qdisc(&ingress_qdisc_ops);
150 }
151 
152 static void __exit ingress_module_exit(void)
153 {
154 	unregister_qdisc(&ingress_qdisc_ops);
155 }
156 
157 module_init(ingress_module_init)
158 module_exit(ingress_module_exit)
159 MODULE_LICENSE("GPL");
160