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         *res = head->res;
  36         return tcf_exts_exec(skb, &head->exts, res);
  37 }
  38
  39 static int mall_init(struct tcf_proto *tp)
  40 {
  41         return 0;
  42 }
  43
  44 static void mall_destroy_rcu(struct rcu_head *rcu)
  45 {
  46         struct cls_mall_head *head = container_of(rcu, struct cls_mall_head,
  47                                                   rcu);
  48
  49         tcf_exts_destroy(&head->exts);
  50         kfree(head);
  51 }
  52
  53 static int mall_replace_hw_filter(struct tcf_proto *tp,
  54                                   struct cls_mall_head *head,
  55                                   unsigned long cookie)
  56 {
  57         struct net_device *dev = tp->q->dev_queue->dev;
  58         struct tc_to_netdev offload;
  59         struct tc_cls_matchall_offload mall_offload = {0};
  60         int err;
  61
  62         offload.type = TC_SETUP_MATCHALL;
  63         offload.cls_mall = &mall_offload;
  64         offload.cls_mall->command = TC_CLSMATCHALL_REPLACE;
  65         offload.cls_mall->exts = &head->exts;
  66         offload.cls_mall->cookie = cookie;
  67
  68         err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
  69                                             tp->chain->index,
  70                                             tp->protocol, &offload);
  71         if (!err)
  72                 head->flags |= TCA_CLS_FLAGS_IN_HW;
  73
  74         return err;
  75 }
  76
  77 static void mall_destroy_hw_filter(struct tcf_proto *tp,
  78                                    struct cls_mall_head *head,
  79                                    unsigned long cookie)
  80 {
  81         struct net_device *dev = tp->q->dev_queue->dev;
  82         struct tc_to_netdev offload;
  83         struct tc_cls_matchall_offload mall_offload = {0};
  84
  85         offload.type = TC_SETUP_MATCHALL;
  86         offload.cls_mall = &mall_offload;
  87         offload.cls_mall->command = TC_CLSMATCHALL_DESTROY;
  88         offload.cls_mall->exts = NULL;
  89         offload.cls_mall->cookie = cookie;
  90
  91         dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->chain->index,
  92                                       tp->protocol, &offload);
  93 }
  94
  95 static void mall_destroy(struct tcf_proto *tp)
  96 {
  97         struct cls_mall_head *head = rtnl_dereference(tp->root);
  98         struct net_device *dev = tp->q->dev_queue->dev;
  99
 100         if (!head)
 101                 return;
 102
 103         if (tc_should_offload(dev, tp, head->flags))
 104                 mall_destroy_hw_filter(tp, head, (unsigned long) head);
 105
 106         call_rcu(&head->rcu, mall_destroy_rcu);
 107 }
 108
 109 static unsigned long mall_get(struct tcf_proto *tp, u32 handle)
 110 {
 111         return 0UL;
 112 }
 113
 114 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 115         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 116         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 117 };
 118
 119 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 120                           struct cls_mall_head *head,
 121                           unsigned long base, struct nlattr **tb,
 122                           struct nlattr *est, bool ovr)
 123 {
 124         struct tcf_exts e;
 125         int err;
 126
 127         err = tcf_exts_init(&e, TCA_MATCHALL_ACT, 0);
 128         if (err)
 129                 return err;
 130         err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
 131         if (err < 0)
 132                 goto errout;
 133
 134         if (tb[TCA_MATCHALL_CLASSID]) {
 135                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 136                 tcf_bind_filter(tp, &head->res, base);
 137         }
 138
 139         tcf_exts_change(tp, &head->exts, &e);
 140
 141         return 0;
 142 errout:
 143         tcf_exts_destroy(&e);
 144         return err;
 145 }
 146
 147 static int mall_change(struct net *net, struct sk_buff *in_skb,
 148                        struct tcf_proto *tp, unsigned long base,
 149                        u32 handle, struct nlattr **tca,
 150                        unsigned long *arg, bool ovr)
 151 {
 152         struct cls_mall_head *head = rtnl_dereference(tp->root);
 153         struct net_device *dev = tp->q->dev_queue->dev;
 154         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 155         struct cls_mall_head *new;
 156         u32 flags = 0;
 157         int err;
 158
 159         if (!tca[TCA_OPTIONS])
 160                 return -EINVAL;
 161
 162         if (head)
 163                 return -EEXIST;
 164
 165         err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
 166                                mall_policy, NULL);
 167         if (err < 0)
 168                 return err;
 169
 170         if (tb[TCA_MATCHALL_FLAGS]) {
 171                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 172                 if (!tc_flags_valid(flags))
 173                         return -EINVAL;
 174         }
 175
 176         new = kzalloc(sizeof(*new), GFP_KERNEL);
 177         if (!new)
 178                 return -ENOBUFS;
 179
 180         err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
 181         if (err)
 182                 goto err_exts_init;
 183
 184         if (!handle)
 185                 handle = 1;
 186         new->handle = handle;
 187         new->flags = flags;
 188
 189         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
 190         if (err)
 191                 goto err_set_parms;
 192
 193         if (tc_should_offload(dev, tp, flags)) {
 194                 err = mall_replace_hw_filter(tp, new, (unsigned long) new);
 195                 if (err) {
 196                         if (tc_skip_sw(flags))
 197                                 goto err_replace_hw_filter;
 198                         else
 199                                 err = 0;
 200                 }
 201         }
 202
 203         if (!tc_in_hw(new->flags))
 204                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 205
 206         *arg = (unsigned long) head;
 207         rcu_assign_pointer(tp->root, new);
 208         return 0;
 209
 210 err_replace_hw_filter:
 211 err_set_parms:
 212         tcf_exts_destroy(&new->exts);
 213 err_exts_init:
 214         kfree(new);
 215         return err;
 216 }
 217
 218 static int mall_delete(struct tcf_proto *tp, unsigned long arg, bool *last)
 219 {
 220         return -EOPNOTSUPP;
 221 }
 222
 223 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 224 {
 225         struct cls_mall_head *head = rtnl_dereference(tp->root);
 226
 227         if (arg->count < arg->skip)
 228                 goto skip;
 229         if (arg->fn(tp, (unsigned long) head, arg) < 0)
 230                 arg->stop = 1;
 231 skip:
 232         arg->count++;
 233 }
 234
 235 static int mall_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 236                      struct sk_buff *skb, struct tcmsg *t)
 237 {
 238         struct cls_mall_head *head = (struct cls_mall_head *) fh;
 239         struct nlattr *nest;
 240
 241         if (!head)
 242                 return skb->len;
 243
 244         t->tcm_handle = head->handle;
 245
 246         nest = nla_nest_start(skb, TCA_OPTIONS);
 247         if (!nest)
 248                 goto nla_put_failure;
 249
 250         if (head->res.classid &&
 251             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 252                 goto nla_put_failure;
 253
 254         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 255                 goto nla_put_failure;
 256
 257         if (tcf_exts_dump(skb, &head->exts))
 258                 goto nla_put_failure;
 259
 260         nla_nest_end(skb, nest);
 261
 262         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 263                 goto nla_put_failure;
 264
 265         return skb->len;
 266
 267 nla_put_failure:
 268         nla_nest_cancel(skb, nest);
 269         return -1;
 270 }
 271
 272 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 273         .kind           = "matchall",
 274         .classify       = mall_classify,
 275         .init           = mall_init,
 276         .destroy        = mall_destroy,
 277         .get            = mall_get,
 278         .change         = mall_change,
 279         .delete         = mall_delete,
 280         .walk           = mall_walk,
 281         .dump           = mall_dump,
 282         .owner          = THIS_MODULE,
 283 };
 284
 285 static int __init cls_mall_init(void)
 286 {
 287         return register_tcf_proto_ops(&cls_mall_ops);
 288 }
 289
 290 static void __exit cls_mall_exit(void)
 291 {
 292         unregister_tcf_proto_ops(&cls_mall_ops);
 293 }
 294
 295 module_init(cls_mall_init);
 296 module_exit(cls_mall_exit);
 297
 298 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 299 MODULE_DESCRIPTION("Match-all classifier");
 300 MODULE_LICENSE("GPL v2");