net/sched/cls_matchall.c

   1 /*
   2  * net/sched/cls_matchll.c              Match-all classifier
   3  *
   4  * Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15
  16 #include <net/sch_generic.h>
  17 #include <net/pkt_cls.h>
  18
  19 struct cls_mall_head {
  20         struct tcf_exts exts;
  21         struct tcf_result res;
  22         u32 handle;
  23         u32 flags;
  24         struct rcu_head rcu;
  25 };
  26
  27 static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
  28                          struct tcf_result *res)
  29 {
  30         struct cls_mall_head *head = rcu_dereference_bh(tp->root);
  31
  32         if (tc_skip_sw(head->flags))
  33                 return -1;
  34
  35         return tcf_exts_exec(skb, &head->exts, res);
  36 }
  37
  38 static int mall_init(struct tcf_proto *tp)
  39 {
  40         return 0;
  41 }
  42
  43 static void mall_destroy_rcu(struct rcu_head *rcu)
  44 {
  45         struct cls_mall_head *head = container_of(rcu, struct cls_mall_head,
  46                                                   rcu);
  47
  48         tcf_exts_destroy(&head->exts);
  49         kfree(head);
  50 }
  51
  52 static int mall_replace_hw_filter(struct tcf_proto *tp,
  53                                   struct cls_mall_head *head,
  54                                   unsigned long cookie)
  55 {
  56         struct net_device *dev = tp->q->dev_queue->dev;
  57         struct tc_to_netdev offload;
  58         struct tc_cls_matchall_offload mall_offload = {0};
  59         int err;
  60
  61         offload.cls_mall = &mall_offload;
  62         offload.cls_mall->command = TC_CLSMATCHALL_REPLACE;
  63         offload.cls_mall->exts = &head->exts;
  64         offload.cls_mall->cookie = cookie;
  65
  66         err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSMATCHALL,
  67                                             tp->q->handle, tp->chain->index,
  68                                             tp->protocol, &offload);
  69         if (!err)
  70                 head->flags |= TCA_CLS_FLAGS_IN_HW;
  71
  72         return err;
  73 }
  74
  75 static void mall_destroy_hw_filter(struct tcf_proto *tp,
  76                                    struct cls_mall_head *head,
  77                                    unsigned long cookie)
  78 {
  79         struct net_device *dev = tp->q->dev_queue->dev;
  80         struct tc_to_netdev offload;
  81         struct tc_cls_matchall_offload mall_offload = {0};
  82
  83         offload.cls_mall = &mall_offload;
  84         offload.cls_mall->command = TC_CLSMATCHALL_DESTROY;
  85         offload.cls_mall->exts = NULL;
  86         offload.cls_mall->cookie = cookie;
  87
  88         dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSMATCHALL, tp->q->handle,
  89                                       tp->chain->index, tp->protocol, &offload);
  90 }
  91
  92 static void mall_destroy(struct tcf_proto *tp)
  93 {
  94         struct cls_mall_head *head = rtnl_dereference(tp->root);
  95         struct net_device *dev = tp->q->dev_queue->dev;
  96
  97         if (!head)
  98                 return;
  99
 100         if (tc_should_offload(dev, tp, head->flags))
 101                 mall_destroy_hw_filter(tp, head, (unsigned long) head);
 102
 103         call_rcu(&head->rcu, mall_destroy_rcu);
 104 }
 105
 106 static unsigned long mall_get(struct tcf_proto *tp, u32 handle)
 107 {
 108         return 0UL;
 109 }
 110
 111 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 112         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 113         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 114 };
 115
 116 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 117                           struct cls_mall_head *head,
 118                           unsigned long base, struct nlattr **tb,
 119                           struct nlattr *est, bool ovr)
 120 {
 121         int err;
 122
 123         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr);
 124         if (err < 0)
 125                 return err;
 126
 127         if (tb[TCA_MATCHALL_CLASSID]) {
 128                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 129                 tcf_bind_filter(tp, &head->res, base);
 130         }
 131         return 0;
 132 }
 133
 134 static int mall_change(struct net *net, struct sk_buff *in_skb,
 135                        struct tcf_proto *tp, unsigned long base,
 136                        u32 handle, struct nlattr **tca,
 137                        unsigned long *arg, bool ovr)
 138 {
 139         struct cls_mall_head *head = rtnl_dereference(tp->root);
 140         struct net_device *dev = tp->q->dev_queue->dev;
 141         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 142         struct cls_mall_head *new;
 143         u32 flags = 0;
 144         int err;
 145
 146         if (!tca[TCA_OPTIONS])
 147                 return -EINVAL;
 148
 149         if (head)
 150                 return -EEXIST;
 151
 152         err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
 153                                mall_policy, NULL);
 154         if (err < 0)
 155                 return err;
 156
 157         if (tb[TCA_MATCHALL_FLAGS]) {
 158                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 159                 if (!tc_flags_valid(flags))
 160                         return -EINVAL;
 161         }
 162
 163         new = kzalloc(sizeof(*new), GFP_KERNEL);
 164         if (!new)
 165                 return -ENOBUFS;
 166
 167         err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
 168         if (err)
 169                 goto err_exts_init;
 170
 171         if (!handle)
 172                 handle = 1;
 173         new->handle = handle;
 174         new->flags = flags;
 175
 176         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
 177         if (err)
 178                 goto err_set_parms;
 179
 180         if (tc_should_offload(dev, tp, flags)) {
 181                 err = mall_replace_hw_filter(tp, new, (unsigned long) new);
 182                 if (err) {
 183                         if (tc_skip_sw(flags))
 184                                 goto err_replace_hw_filter;
 185                         else
 186                                 err = 0;
 187                 }
 188         }
 189
 190         if (!tc_in_hw(new->flags))
 191                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 192
 193         *arg = (unsigned long) head;
 194         rcu_assign_pointer(tp->root, new);
 195         return 0;
 196
 197 err_replace_hw_filter:
 198 err_set_parms:
 199         tcf_exts_destroy(&new->exts);
 200 err_exts_init:
 201         kfree(new);
 202         return err;
 203 }
 204
 205 static int mall_delete(struct tcf_proto *tp, unsigned long arg, bool *last)
 206 {
 207         return -EOPNOTSUPP;
 208 }
 209
 210 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 211 {
 212         struct cls_mall_head *head = rtnl_dereference(tp->root);
 213
 214         if (arg->count < arg->skip)
 215                 goto skip;
 216         if (arg->fn(tp, (unsigned long) head, arg) < 0)
 217                 arg->stop = 1;
 218 skip:
 219         arg->count++;
 220 }
 221
 222 static int mall_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 223                      struct sk_buff *skb, struct tcmsg *t)
 224 {
 225         struct cls_mall_head *head = (struct cls_mall_head *) fh;
 226         struct nlattr *nest;
 227
 228         if (!head)
 229                 return skb->len;
 230
 231         t->tcm_handle = head->handle;
 232
 233         nest = nla_nest_start(skb, TCA_OPTIONS);
 234         if (!nest)
 235                 goto nla_put_failure;
 236
 237         if (head->res.classid &&
 238             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 239                 goto nla_put_failure;
 240
 241         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 242                 goto nla_put_failure;
 243
 244         if (tcf_exts_dump(skb, &head->exts))
 245                 goto nla_put_failure;
 246
 247         nla_nest_end(skb, nest);
 248
 249         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 250                 goto nla_put_failure;
 251
 252         return skb->len;
 253
 254 nla_put_failure:
 255         nla_nest_cancel(skb, nest);
 256         return -1;
 257 }
 258
 259 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 260         .kind           = "matchall",
 261         .classify       = mall_classify,
 262         .init           = mall_init,
 263         .destroy        = mall_destroy,
 264         .get            = mall_get,
 265         .change         = mall_change,
 266         .delete         = mall_delete,
 267         .walk           = mall_walk,
 268         .dump           = mall_dump,
 269         .owner          = THIS_MODULE,
 270 };
 271
 272 static int __init cls_mall_init(void)
 273 {
 274         return register_tcf_proto_ops(&cls_mall_ops);
 275 }
 276
 277 static void __exit cls_mall_exit(void)
 278 {
 279         unregister_tcf_proto_ops(&cls_mall_ops);
 280 }
 281
 282 module_init(cls_mall_init);
 283 module_exit(cls_mall_exit);
 284
 285 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 286 MODULE_DESCRIPTION("Match-all classifier");
 287 MODULE_LICENSE("GPL v2");