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         union {
  25                 struct work_struct work;
  26                 struct rcu_head rcu;
  27         };
  28 };
  29
  30 static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
  31                          struct tcf_result *res)
  32 {
  33         struct cls_mall_head *head = rcu_dereference_bh(tp->root);
  34
  35         if (tc_skip_sw(head->flags))
  36                 return -1;
  37
  38         *res = head->res;
  39         return tcf_exts_exec(skb, &head->exts, res);
  40 }
  41
  42 static int mall_init(struct tcf_proto *tp)
  43 {
  44         return 0;
  45 }
  46
  47 static void mall_destroy_work(struct work_struct *work)
  48 {
  49         struct cls_mall_head *head = container_of(work, struct cls_mall_head,
  50                                                   work);
  51         rtnl_lock();
  52         tcf_exts_destroy(&head->exts);
  53         kfree(head);
  54         rtnl_unlock();
  55 }
  56
  57 static void mall_destroy_rcu(struct rcu_head *rcu)
  58 {
  59         struct cls_mall_head *head = container_of(rcu, struct cls_mall_head,
  60                                                   rcu);
  61
  62         INIT_WORK(&head->work, mall_destroy_work);
  63         tcf_queue_work(&head->work);
  64 }
  65
  66 static int mall_replace_hw_filter(struct tcf_proto *tp,
  67                                   struct cls_mall_head *head,
  68                                   unsigned long cookie)
  69 {
  70         struct net_device *dev = tp->q->dev_queue->dev;
  71         struct tc_cls_matchall_offload cls_mall = {};
  72         int err;
  73
  74         tc_cls_common_offload_init(&cls_mall.common, tp);
  75         cls_mall.command = TC_CLSMATCHALL_REPLACE;
  76         cls_mall.exts = &head->exts;
  77         cls_mall.cookie = cookie;
  78
  79         err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSMATCHALL,
  80                                             &cls_mall);
  81         if (!err)
  82                 head->flags |= TCA_CLS_FLAGS_IN_HW;
  83
  84         return err;
  85 }
  86
  87 static void mall_destroy_hw_filter(struct tcf_proto *tp,
  88                                    struct cls_mall_head *head,
  89                                    unsigned long cookie)
  90 {
  91         struct net_device *dev = tp->q->dev_queue->dev;
  92         struct tc_cls_matchall_offload cls_mall = {};
  93
  94         tc_cls_common_offload_init(&cls_mall.common, tp);
  95         cls_mall.command = TC_CLSMATCHALL_DESTROY;
  96         cls_mall.cookie = cookie;
  97
  98         dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSMATCHALL, &cls_mall);
  99 }
 100
 101 static void mall_destroy(struct tcf_proto *tp)
 102 {
 103         struct cls_mall_head *head = rtnl_dereference(tp->root);
 104         struct net_device *dev = tp->q->dev_queue->dev;
 105
 106         if (!head)
 107                 return;
 108
 109         if (tc_should_offload(dev, head->flags))
 110                 mall_destroy_hw_filter(tp, head, (unsigned long) head);
 111
 112         call_rcu(&head->rcu, mall_destroy_rcu);
 113 }
 114
 115 static void *mall_get(struct tcf_proto *tp, u32 handle)
 116 {
 117         return NULL;
 118 }
 119
 120 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 121         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 122         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 123 };
 124
 125 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 126                           struct cls_mall_head *head,
 127                           unsigned long base, struct nlattr **tb,
 128                           struct nlattr *est, bool ovr)
 129 {
 130         int err;
 131
 132         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr);
 133         if (err < 0)
 134                 return err;
 135
 136         if (tb[TCA_MATCHALL_CLASSID]) {
 137                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 138                 tcf_bind_filter(tp, &head->res, base);
 139         }
 140         return 0;
 141 }
 142
 143 static int mall_change(struct net *net, struct sk_buff *in_skb,
 144                        struct tcf_proto *tp, unsigned long base,
 145                        u32 handle, struct nlattr **tca,
 146                        void **arg, bool ovr)
 147 {
 148         struct cls_mall_head *head = rtnl_dereference(tp->root);
 149         struct net_device *dev = tp->q->dev_queue->dev;
 150         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 151         struct cls_mall_head *new;
 152         u32 flags = 0;
 153         int err;
 154
 155         if (!tca[TCA_OPTIONS])
 156                 return -EINVAL;
 157
 158         if (head)
 159                 return -EEXIST;
 160
 161         err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
 162                                mall_policy, NULL);
 163         if (err < 0)
 164                 return err;
 165
 166         if (tb[TCA_MATCHALL_FLAGS]) {
 167                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 168                 if (!tc_flags_valid(flags))
 169                         return -EINVAL;
 170         }
 171
 172         new = kzalloc(sizeof(*new), GFP_KERNEL);
 173         if (!new)
 174                 return -ENOBUFS;
 175
 176         err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
 177         if (err)
 178                 goto err_exts_init;
 179
 180         if (!handle)
 181                 handle = 1;
 182         new->handle = handle;
 183         new->flags = flags;
 184
 185         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
 186         if (err)
 187                 goto err_set_parms;
 188
 189         if (tc_should_offload(dev, flags)) {
 190                 err = mall_replace_hw_filter(tp, new, (unsigned long) new);
 191                 if (err) {
 192                         if (tc_skip_sw(flags))
 193                                 goto err_replace_hw_filter;
 194                         else
 195                                 err = 0;
 196                 }
 197         }
 198
 199         if (!tc_in_hw(new->flags))
 200                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 201
 202         *arg = head;
 203         rcu_assign_pointer(tp->root, new);
 204         return 0;
 205
 206 err_replace_hw_filter:
 207 err_set_parms:
 208         tcf_exts_destroy(&new->exts);
 209 err_exts_init:
 210         kfree(new);
 211         return err;
 212 }
 213
 214 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last)
 215 {
 216         return -EOPNOTSUPP;
 217 }
 218
 219 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 220 {
 221         struct cls_mall_head *head = rtnl_dereference(tp->root);
 222
 223         if (arg->count < arg->skip)
 224                 goto skip;
 225         if (arg->fn(tp, head, arg) < 0)
 226                 arg->stop = 1;
 227 skip:
 228         arg->count++;
 229 }
 230
 231 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
 232                      struct sk_buff *skb, struct tcmsg *t)
 233 {
 234         struct cls_mall_head *head = fh;
 235         struct nlattr *nest;
 236
 237         if (!head)
 238                 return skb->len;
 239
 240         t->tcm_handle = head->handle;
 241
 242         nest = nla_nest_start(skb, TCA_OPTIONS);
 243         if (!nest)
 244                 goto nla_put_failure;
 245
 246         if (head->res.classid &&
 247             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 248                 goto nla_put_failure;
 249
 250         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 251                 goto nla_put_failure;
 252
 253         if (tcf_exts_dump(skb, &head->exts))
 254                 goto nla_put_failure;
 255
 256         nla_nest_end(skb, nest);
 257
 258         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 259                 goto nla_put_failure;
 260
 261         return skb->len;
 262
 263 nla_put_failure:
 264         nla_nest_cancel(skb, nest);
 265         return -1;
 266 }
 267
 268 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
 269 {
 270         struct cls_mall_head *head = fh;
 271
 272         if (head && head->res.classid == classid)
 273                 head->res.class = cl;
 274 }
 275
 276 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 277         .kind           = "matchall",
 278         .classify       = mall_classify,
 279         .init           = mall_init,
 280         .destroy        = mall_destroy,
 281         .get            = mall_get,
 282         .change         = mall_change,
 283         .delete         = mall_delete,
 284         .walk           = mall_walk,
 285         .dump           = mall_dump,
 286         .bind_class     = mall_bind_class,
 287         .owner          = THIS_MODULE,
 288 };
 289
 290 static int __init cls_mall_init(void)
 291 {
 292         return register_tcf_proto_ops(&cls_mall_ops);
 293 }
 294
 295 static void __exit cls_mall_exit(void)
 296 {
 297         unregister_tcf_proto_ops(&cls_mall_ops);
 298 }
 299
 300 module_init(cls_mall_init);
 301 module_exit(cls_mall_exit);
 302
 303 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 304 MODULE_DESCRIPTION("Match-all classifier");
 305 MODULE_LICENSE("GPL v2");