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