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.type = TC_SETUP_MATCHALL;
  62         offload.cls_mall = &mall_offload;
  63         offload.cls_mall->command = TC_CLSMATCHALL_REPLACE;
  64         offload.cls_mall->exts = &head->exts;
  65         offload.cls_mall->cookie = cookie;
  66
  67         err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol,
  68                                             &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.type = TC_SETUP_MATCHALL;
  84         offload.cls_mall = &mall_offload;
  85         offload.cls_mall->command = TC_CLSMATCHALL_DESTROY;
  86         offload.cls_mall->exts = NULL;
  87         offload.cls_mall->cookie = cookie;
  88
  89         dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol,
  90                                              &offload);
  91 }
  92
  93 static bool mall_destroy(struct tcf_proto *tp, bool force)
  94 {
  95         struct cls_mall_head *head = rtnl_dereference(tp->root);
  96         struct net_device *dev = tp->q->dev_queue->dev;
  97
  98         if (!head)
  99                 return true;
 100
 101         if (tc_should_offload(dev, tp, head->flags))
 102                 mall_destroy_hw_filter(tp, head, (unsigned long) head);
 103
 104         call_rcu(&head->rcu, mall_destroy_rcu);
 105         return true;
 106 }
 107
 108 static unsigned long mall_get(struct tcf_proto *tp, u32 handle)
 109 {
 110         return 0UL;
 111 }
 112
 113 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 114         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 115         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 116 };
 117
 118 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 119                           struct cls_mall_head *head,
 120                           unsigned long base, struct nlattr **tb,
 121                           struct nlattr *est, bool ovr)
 122 {
 123         struct tcf_exts e;
 124         int err;
 125
 126         err = tcf_exts_init(&e, TCA_MATCHALL_ACT, 0);
 127         if (err)
 128                 return err;
 129         err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
 130         if (err < 0)
 131                 goto errout;
 132
 133         if (tb[TCA_MATCHALL_CLASSID]) {
 134                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 135                 tcf_bind_filter(tp, &head->res, base);
 136         }
 137
 138         tcf_exts_change(tp, &head->exts, &e);
 139
 140         return 0;
 141 errout:
 142         tcf_exts_destroy(&e);
 143         return err;
 144 }
 145
 146 static int mall_change(struct net *net, struct sk_buff *in_skb,
 147                        struct tcf_proto *tp, unsigned long base,
 148                        u32 handle, struct nlattr **tca,
 149                        unsigned long *arg, bool ovr)
 150 {
 151         struct cls_mall_head *head = rtnl_dereference(tp->root);
 152         struct net_device *dev = tp->q->dev_queue->dev;
 153         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 154         struct cls_mall_head *new;
 155         u32 flags = 0;
 156         int err;
 157
 158         if (!tca[TCA_OPTIONS])
 159                 return -EINVAL;
 160
 161         if (head)
 162                 return -EEXIST;
 163
 164         err = nla_parse_nested(tb, TCA_MATCHALL_MAX,
 165                                tca[TCA_OPTIONS], mall_policy);
 166         if (err < 0)
 167                 return err;
 168
 169         if (tb[TCA_MATCHALL_FLAGS]) {
 170                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 171                 if (!tc_flags_valid(flags))
 172                         return -EINVAL;
 173         }
 174
 175         new = kzalloc(sizeof(*new), GFP_KERNEL);
 176         if (!new)
 177                 return -ENOBUFS;
 178
 179         err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
 180         if (err)
 181                 goto err_exts_init;
 182
 183         if (!handle)
 184                 handle = 1;
 185         new->handle = handle;
 186         new->flags = flags;
 187
 188         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
 189         if (err)
 190                 goto err_set_parms;
 191
 192         if (tc_should_offload(dev, tp, flags)) {
 193                 err = mall_replace_hw_filter(tp, new, (unsigned long) new);
 194                 if (err) {
 195                         if (tc_skip_sw(flags))
 196                                 goto err_replace_hw_filter;
 197                         else
 198                                 err = 0;
 199                 }
 200         }
 201
 202         if (!tc_in_hw(new->flags))
 203                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 204
 205         *arg = (unsigned long) head;
 206         rcu_assign_pointer(tp->root, new);
 207         if (head)
 208                 call_rcu(&head->rcu, mall_destroy_rcu);
 209         return 0;
 210
 211 err_replace_hw_filter:
 212 err_set_parms:
 213         tcf_exts_destroy(&new->exts);
 214 err_exts_init:
 215         kfree(new);
 216         return err;
 217 }
 218
 219 static int mall_delete(struct tcf_proto *tp, unsigned long arg)
 220 {
 221         return -EOPNOTSUPP;
 222 }
 223
 224 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 225 {
 226         struct cls_mall_head *head = rtnl_dereference(tp->root);
 227
 228         if (arg->count < arg->skip)
 229                 goto skip;
 230         if (arg->fn(tp, (unsigned long) head, arg) < 0)
 231                 arg->stop = 1;
 232 skip:
 233         arg->count++;
 234 }
 235
 236 static int mall_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 237                      struct sk_buff *skb, struct tcmsg *t)
 238 {
 239         struct cls_mall_head *head = (struct cls_mall_head *) fh;
 240         struct nlattr *nest;
 241
 242         if (!head)
 243                 return skb->len;
 244
 245         t->tcm_handle = head->handle;
 246
 247         nest = nla_nest_start(skb, TCA_OPTIONS);
 248         if (!nest)
 249                 goto nla_put_failure;
 250
 251         if (head->res.classid &&
 252             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 253                 goto nla_put_failure;
 254
 255         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 256                 goto nla_put_failure;
 257
 258         if (tcf_exts_dump(skb, &head->exts))
 259                 goto nla_put_failure;
 260
 261         nla_nest_end(skb, nest);
 262
 263         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 264                 goto nla_put_failure;
 265
 266         return skb->len;
 267
 268 nla_put_failure:
 269         nla_nest_cancel(skb, nest);
 270         return -1;
 271 }
 272
 273 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 274         .kind           = "matchall",
 275         .classify       = mall_classify,
 276         .init           = mall_init,
 277         .destroy        = mall_destroy,
 278         .get            = mall_get,
 279         .change         = mall_change,
 280         .delete         = mall_delete,
 281         .walk           = mall_walk,
 282         .dump           = mall_dump,
 283         .owner          = THIS_MODULE,
 284 };
 285
 286 static int __init cls_mall_init(void)
 287 {
 288         return register_tcf_proto_ops(&cls_mall_ops);
 289 }
 290
 291 static void __exit cls_mall_exit(void)
 292 {
 293         unregister_tcf_proto_ops(&cls_mall_ops);
 294 }
 295
 296 module_init(cls_mall_init);
 297 module_exit(cls_mall_exit);
 298
 299 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 300 MODULE_DESCRIPTION("Match-all classifier");
 301 MODULE_LICENSE("GPL v2");