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 #include <linux/percpu.h>
  16
  17 #include <net/sch_generic.h>
  18 #include <net/pkt_cls.h>
  19
  20 struct cls_mall_head {
  21         struct tcf_exts exts;
  22         struct tcf_result res;
  23         u32 handle;
  24         u32 flags;
  25         unsigned int in_hw_count;
  26         struct tc_matchall_pcnt __percpu *pf;
  27         struct rcu_work rwork;
  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 (unlikely(!head))
  36                 return -1;
  37
  38         if (tc_skip_sw(head->flags))
  39                 return -1;
  40
  41         *res = head->res;
  42         __this_cpu_inc(head->pf->rhit);
  43         return tcf_exts_exec(skb, &head->exts, res);
  44 }
  45
  46 static int mall_init(struct tcf_proto *tp)
  47 {
  48         return 0;
  49 }
  50
  51 static void __mall_destroy(struct cls_mall_head *head)
  52 {
  53         tcf_exts_destroy(&head->exts);
  54         tcf_exts_put_net(&head->exts);
  55         free_percpu(head->pf);
  56         kfree(head);
  57 }
  58
  59 static void mall_destroy_work(struct work_struct *work)
  60 {
  61         struct cls_mall_head *head = container_of(to_rcu_work(work),
  62                                                   struct cls_mall_head,
  63                                                   rwork);
  64         rtnl_lock();
  65         __mall_destroy(head);
  66         rtnl_unlock();
  67 }
  68
  69 static void mall_destroy_hw_filter(struct tcf_proto *tp,
  70                                    struct cls_mall_head *head,
  71                                    unsigned long cookie,
  72                                    struct netlink_ext_ack *extack)
  73 {
  74         struct tc_cls_matchall_offload cls_mall = {};
  75         struct tcf_block *block = tp->chain->block;
  76
  77         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  78         cls_mall.command = TC_CLSMATCHALL_DESTROY;
  79         cls_mall.cookie = cookie;
  80
  81         tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
  82         tcf_block_offload_dec(block, &head->flags);
  83 }
  84
  85 static int mall_replace_hw_filter(struct tcf_proto *tp,
  86                                   struct cls_mall_head *head,
  87                                   unsigned long cookie,
  88                                   struct netlink_ext_ack *extack)
  89 {
  90         struct tc_cls_matchall_offload cls_mall = {};
  91         struct tcf_block *block = tp->chain->block;
  92         bool skip_sw = tc_skip_sw(head->flags);
  93         int err;
  94
  95         cls_mall.rule = flow_rule_alloc(tcf_exts_num_actions(&head->exts));
  96         if (!cls_mall.rule)
  97                 return -ENOMEM;
  98
  99         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
 100         cls_mall.command = TC_CLSMATCHALL_REPLACE;
 101         cls_mall.cookie = cookie;
 102
 103         err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts);
 104         if (err) {
 105                 kfree(cls_mall.rule);
 106                 mall_destroy_hw_filter(tp, head, cookie, NULL);
 107                 if (skip_sw)
 108                         NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
 109                 else
 110                         err = 0;
 111
 112                 return err;
 113         }
 114
 115         err = tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, skip_sw);
 116         kfree(cls_mall.rule);
 117
 118         if (err < 0) {
 119                 mall_destroy_hw_filter(tp, head, cookie, NULL);
 120                 return err;
 121         } else if (err > 0) {
 122                 head->in_hw_count = err;
 123                 tcf_block_offload_inc(block, &head->flags);
 124         }
 125
 126         if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
 127                 return -EINVAL;
 128
 129         return 0;
 130 }
 131
 132 static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
 133                          struct netlink_ext_ack *extack)
 134 {
 135         struct cls_mall_head *head = rtnl_dereference(tp->root);
 136
 137         if (!head)
 138                 return;
 139
 140         tcf_unbind_filter(tp, &head->res);
 141
 142         if (!tc_skip_hw(head->flags))
 143                 mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
 144
 145         if (tcf_exts_get_net(&head->exts))
 146                 tcf_queue_work(&head->rwork, mall_destroy_work);
 147         else
 148                 __mall_destroy(head);
 149 }
 150
 151 static void *mall_get(struct tcf_proto *tp, u32 handle)
 152 {
 153         struct cls_mall_head *head = rtnl_dereference(tp->root);
 154
 155         if (head && head->handle == handle)
 156                 return head;
 157
 158         return NULL;
 159 }
 160
 161 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 162         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 163         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 164 };
 165
 166 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 167                           struct cls_mall_head *head,
 168                           unsigned long base, struct nlattr **tb,
 169                           struct nlattr *est, bool ovr,
 170                           struct netlink_ext_ack *extack)
 171 {
 172         int err;
 173
 174         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, true,
 175                                 extack);
 176         if (err < 0)
 177                 return err;
 178
 179         if (tb[TCA_MATCHALL_CLASSID]) {
 180                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 181                 tcf_bind_filter(tp, &head->res, base);
 182         }
 183         return 0;
 184 }
 185
 186 static int mall_change(struct net *net, struct sk_buff *in_skb,
 187                        struct tcf_proto *tp, unsigned long base,
 188                        u32 handle, struct nlattr **tca,
 189                        void **arg, bool ovr, bool rtnl_held,
 190                        struct netlink_ext_ack *extack)
 191 {
 192         struct cls_mall_head *head = rtnl_dereference(tp->root);
 193         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 194         struct cls_mall_head *new;
 195         u32 flags = 0;
 196         int err;
 197
 198         if (!tca[TCA_OPTIONS])
 199                 return -EINVAL;
 200
 201         if (head)
 202                 return -EEXIST;
 203
 204         err = nla_parse_nested_deprecated(tb, TCA_MATCHALL_MAX,
 205                                           tca[TCA_OPTIONS], mall_policy, NULL);
 206         if (err < 0)
 207                 return err;
 208
 209         if (tb[TCA_MATCHALL_FLAGS]) {
 210                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 211                 if (!tc_flags_valid(flags))
 212                         return -EINVAL;
 213         }
 214
 215         new = kzalloc(sizeof(*new), GFP_KERNEL);
 216         if (!new)
 217                 return -ENOBUFS;
 218
 219         err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
 220         if (err)
 221                 goto err_exts_init;
 222
 223         if (!handle)
 224                 handle = 1;
 225         new->handle = handle;
 226         new->flags = flags;
 227         new->pf = alloc_percpu(struct tc_matchall_pcnt);
 228         if (!new->pf) {
 229                 err = -ENOMEM;
 230                 goto err_alloc_percpu;
 231         }
 232
 233         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
 234                              extack);
 235         if (err)
 236                 goto err_set_parms;
 237
 238         if (!tc_skip_hw(new->flags)) {
 239                 err = mall_replace_hw_filter(tp, new, (unsigned long)new,
 240                                              extack);
 241                 if (err)
 242                         goto err_replace_hw_filter;
 243         }
 244
 245         if (!tc_in_hw(new->flags))
 246                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 247
 248         *arg = head;
 249         rcu_assign_pointer(tp->root, new);
 250         return 0;
 251
 252 err_replace_hw_filter:
 253 err_set_parms:
 254         free_percpu(new->pf);
 255 err_alloc_percpu:
 256         tcf_exts_destroy(&new->exts);
 257 err_exts_init:
 258         kfree(new);
 259         return err;
 260 }
 261
 262 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
 263                        bool rtnl_held, struct netlink_ext_ack *extack)
 264 {
 265         return -EOPNOTSUPP;
 266 }
 267
 268 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 269                       bool rtnl_held)
 270 {
 271         struct cls_mall_head *head = rtnl_dereference(tp->root);
 272
 273         if (arg->count < arg->skip)
 274                 goto skip;
 275
 276         if (!head)
 277                 return;
 278         if (arg->fn(tp, head, arg) < 0)
 279                 arg->stop = 1;
 280 skip:
 281         arg->count++;
 282 }
 283
 284 static int mall_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
 285                           void *cb_priv, struct netlink_ext_ack *extack)
 286 {
 287         struct cls_mall_head *head = rtnl_dereference(tp->root);
 288         struct tc_cls_matchall_offload cls_mall = {};
 289         struct tcf_block *block = tp->chain->block;
 290         int err;
 291
 292         if (tc_skip_hw(head->flags))
 293                 return 0;
 294
 295         cls_mall.rule = flow_rule_alloc(tcf_exts_num_actions(&head->exts));
 296         if (!cls_mall.rule)
 297                 return -ENOMEM;
 298
 299         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
 300         cls_mall.command = add ?
 301                 TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
 302         cls_mall.cookie = (unsigned long)head;
 303
 304         err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts);
 305         if (err) {
 306                 kfree(cls_mall.rule);
 307                 if (add && tc_skip_sw(head->flags)) {
 308                         NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
 309                         return err;
 310                 }
 311                 return 0;
 312         }
 313
 314         err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
 315         kfree(cls_mall.rule);
 316
 317         if (err) {
 318                 if (add && tc_skip_sw(head->flags))
 319                         return err;
 320                 return 0;
 321         }
 322
 323         tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
 324
 325         return 0;
 326 }
 327
 328 static void mall_stats_hw_filter(struct tcf_proto *tp,
 329                                  struct cls_mall_head *head,
 330                                  unsigned long cookie)
 331 {
 332         struct tc_cls_matchall_offload cls_mall = {};
 333         struct tcf_block *block = tp->chain->block;
 334
 335         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, NULL);
 336         cls_mall.command = TC_CLSMATCHALL_STATS;
 337         cls_mall.cookie = cookie;
 338
 339         tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
 340
 341         tcf_exts_stats_update(&head->exts, cls_mall.stats.bytes,
 342                               cls_mall.stats.pkts, cls_mall.stats.lastused);
 343 }
 344
 345 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
 346                      struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
 347 {
 348         struct tc_matchall_pcnt gpf = {};
 349         struct cls_mall_head *head = fh;
 350         struct nlattr *nest;
 351         int cpu;
 352
 353         if (!head)
 354                 return skb->len;
 355
 356         if (!tc_skip_hw(head->flags))
 357                 mall_stats_hw_filter(tp, head, (unsigned long)head);
 358
 359         t->tcm_handle = head->handle;
 360
 361         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 362         if (!nest)
 363                 goto nla_put_failure;
 364
 365         if (head->res.classid &&
 366             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 367                 goto nla_put_failure;
 368
 369         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 370                 goto nla_put_failure;
 371
 372         for_each_possible_cpu(cpu) {
 373                 struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
 374
 375                 gpf.rhit += pf->rhit;
 376         }
 377
 378         if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
 379                           sizeof(struct tc_matchall_pcnt),
 380                           &gpf, TCA_MATCHALL_PAD))
 381                 goto nla_put_failure;
 382
 383         if (tcf_exts_dump(skb, &head->exts))
 384                 goto nla_put_failure;
 385
 386         nla_nest_end(skb, nest);
 387
 388         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 389                 goto nla_put_failure;
 390
 391         return skb->len;
 392
 393 nla_put_failure:
 394         nla_nest_cancel(skb, nest);
 395         return -1;
 396 }
 397
 398 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
 399 {
 400         struct cls_mall_head *head = fh;
 401
 402         if (head && head->res.classid == classid)
 403                 head->res.class = cl;
 404 }
 405
 406 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 407         .kind           = "matchall",
 408         .classify       = mall_classify,
 409         .init           = mall_init,
 410         .destroy        = mall_destroy,
 411         .get            = mall_get,
 412         .change         = mall_change,
 413         .delete         = mall_delete,
 414         .walk           = mall_walk,
 415         .reoffload      = mall_reoffload,
 416         .dump           = mall_dump,
 417         .bind_class     = mall_bind_class,
 418         .owner          = THIS_MODULE,
 419 };
 420
 421 static int __init cls_mall_init(void)
 422 {
 423         return register_tcf_proto_ops(&cls_mall_ops);
 424 }
 425
 426 static void __exit cls_mall_exit(void)
 427 {
 428         unregister_tcf_proto_ops(&cls_mall_ops);
 429 }
 430
 431 module_init(cls_mall_init);
 432 module_exit(cls_mall_exit);
 433
 434 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 435 MODULE_DESCRIPTION("Match-all classifier");
 436 MODULE_LICENSE("GPL v2");