net/sched/cls_matchall.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * net/sched/cls_matchll.c              Match-all classifier
   4  *
   5  * Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com>
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11 #include <linux/percpu.h>
  12
  13 #include <net/sch_generic.h>
  14 #include <net/pkt_cls.h>
  15
  16 struct cls_mall_head {
  17         struct tcf_exts exts;
  18         struct tcf_result res;
  19         u32 handle;
  20         u32 flags;
  21         unsigned int in_hw_count;
  22         struct tc_matchall_pcnt __percpu *pf;
  23         struct rcu_work rwork;
  24 };
  25
  26 static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
  27                          struct tcf_result *res)
  28 {
  29         struct cls_mall_head *head = rcu_dereference_bh(tp->root);
  30
  31         if (unlikely(!head))
  32                 return -1;
  33
  34         if (tc_skip_sw(head->flags))
  35                 return -1;
  36
  37         *res = head->res;
  38         __this_cpu_inc(head->pf->rhit);
  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(struct cls_mall_head *head)
  48 {
  49         tcf_exts_destroy(&head->exts);
  50         tcf_exts_put_net(&head->exts);
  51         free_percpu(head->pf);
  52         kfree(head);
  53 }
  54
  55 static void mall_destroy_work(struct work_struct *work)
  56 {
  57         struct cls_mall_head *head = container_of(to_rcu_work(work),
  58                                                   struct cls_mall_head,
  59                                                   rwork);
  60         rtnl_lock();
  61         __mall_destroy(head);
  62         rtnl_unlock();
  63 }
  64
  65 static void mall_destroy_hw_filter(struct tcf_proto *tp,
  66                                    struct cls_mall_head *head,
  67                                    unsigned long cookie,
  68                                    struct netlink_ext_ack *extack)
  69 {
  70         struct tc_cls_matchall_offload cls_mall = {};
  71         struct tcf_block *block = tp->chain->block;
  72
  73         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  74         cls_mall.command = TC_CLSMATCHALL_DESTROY;
  75         cls_mall.cookie = cookie;
  76
  77         tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
  78         tcf_block_offload_dec(block, &head->flags);
  79 }
  80
  81 static int mall_replace_hw_filter(struct tcf_proto *tp,
  82                                   struct cls_mall_head *head,
  83                                   unsigned long cookie,
  84                                   struct netlink_ext_ack *extack)
  85 {
  86         struct tc_cls_matchall_offload cls_mall = {};
  87         struct tcf_block *block = tp->chain->block;
  88         bool skip_sw = tc_skip_sw(head->flags);
  89         int err;
  90
  91         cls_mall.rule = flow_rule_alloc(tcf_exts_num_actions(&head->exts));
  92         if (!cls_mall.rule)
  93                 return -ENOMEM;
  94
  95         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  96         cls_mall.command = TC_CLSMATCHALL_REPLACE;
  97         cls_mall.cookie = cookie;
  98
  99         err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts);
 100         if (err) {
 101                 kfree(cls_mall.rule);
 102                 mall_destroy_hw_filter(tp, head, cookie, NULL);
 103                 if (skip_sw)
 104                         NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
 105                 else
 106                         err = 0;
 107
 108                 return err;
 109         }
 110
 111         err = tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, skip_sw);
 112         kfree(cls_mall.rule);
 113
 114         if (err < 0) {
 115                 mall_destroy_hw_filter(tp, head, cookie, NULL);
 116                 return err;
 117         } else if (err > 0) {
 118                 head->in_hw_count = err;
 119                 tcf_block_offload_inc(block, &head->flags);
 120         }
 121
 122         if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
 123                 return -EINVAL;
 124
 125         return 0;
 126 }
 127
 128 static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
 129                          struct netlink_ext_ack *extack)
 130 {
 131         struct cls_mall_head *head = rtnl_dereference(tp->root);
 132
 133         if (!head)
 134                 return;
 135
 136         tcf_unbind_filter(tp, &head->res);
 137
 138         if (!tc_skip_hw(head->flags))
 139                 mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
 140
 141         if (tcf_exts_get_net(&head->exts))
 142                 tcf_queue_work(&head->rwork, mall_destroy_work);
 143         else
 144                 __mall_destroy(head);
 145 }
 146
 147 static void *mall_get(struct tcf_proto *tp, u32 handle)
 148 {
 149         struct cls_mall_head *head = rtnl_dereference(tp->root);
 150
 151         if (head && head->handle == handle)
 152                 return head;
 153
 154         return NULL;
 155 }
 156
 157 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 158         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 159         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 160 };
 161
 162 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 163                           struct cls_mall_head *head,
 164                           unsigned long base, struct nlattr **tb,
 165                           struct nlattr *est, bool ovr,
 166                           struct netlink_ext_ack *extack)
 167 {
 168         int err;
 169
 170         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, true,
 171                                 extack);
 172         if (err < 0)
 173                 return err;
 174
 175         if (tb[TCA_MATCHALL_CLASSID]) {
 176                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 177                 tcf_bind_filter(tp, &head->res, base);
 178         }
 179         return 0;
 180 }
 181
 182 static int mall_change(struct net *net, struct sk_buff *in_skb,
 183                        struct tcf_proto *tp, unsigned long base,
 184                        u32 handle, struct nlattr **tca,
 185                        void **arg, bool ovr, bool rtnl_held,
 186                        struct netlink_ext_ack *extack)
 187 {
 188         struct cls_mall_head *head = rtnl_dereference(tp->root);
 189         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 190         struct cls_mall_head *new;
 191         u32 flags = 0;
 192         int err;
 193
 194         if (!tca[TCA_OPTIONS])
 195                 return -EINVAL;
 196
 197         if (head)
 198                 return -EEXIST;
 199
 200         err = nla_parse_nested_deprecated(tb, TCA_MATCHALL_MAX,
 201                                           tca[TCA_OPTIONS], mall_policy, NULL);
 202         if (err < 0)
 203                 return err;
 204
 205         if (tb[TCA_MATCHALL_FLAGS]) {
 206                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 207                 if (!tc_flags_valid(flags))
 208                         return -EINVAL;
 209         }
 210
 211         new = kzalloc(sizeof(*new), GFP_KERNEL);
 212         if (!new)
 213                 return -ENOBUFS;
 214
 215         err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
 216         if (err)
 217                 goto err_exts_init;
 218
 219         if (!handle)
 220                 handle = 1;
 221         new->handle = handle;
 222         new->flags = flags;
 223         new->pf = alloc_percpu(struct tc_matchall_pcnt);
 224         if (!new->pf) {
 225                 err = -ENOMEM;
 226                 goto err_alloc_percpu;
 227         }
 228
 229         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
 230                              extack);
 231         if (err)
 232                 goto err_set_parms;
 233
 234         if (!tc_skip_hw(new->flags)) {
 235                 err = mall_replace_hw_filter(tp, new, (unsigned long)new,
 236                                              extack);
 237                 if (err)
 238                         goto err_replace_hw_filter;
 239         }
 240
 241         if (!tc_in_hw(new->flags))
 242                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 243
 244         *arg = head;
 245         rcu_assign_pointer(tp->root, new);
 246         return 0;
 247
 248 err_replace_hw_filter:
 249 err_set_parms:
 250         free_percpu(new->pf);
 251 err_alloc_percpu:
 252         tcf_exts_destroy(&new->exts);
 253 err_exts_init:
 254         kfree(new);
 255         return err;
 256 }
 257
 258 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
 259                        bool rtnl_held, struct netlink_ext_ack *extack)
 260 {
 261         return -EOPNOTSUPP;
 262 }
 263
 264 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 265                       bool rtnl_held)
 266 {
 267         struct cls_mall_head *head = rtnl_dereference(tp->root);
 268
 269         if (arg->count < arg->skip)
 270                 goto skip;
 271
 272         if (!head)
 273                 return;
 274         if (arg->fn(tp, head, arg) < 0)
 275                 arg->stop = 1;
 276 skip:
 277         arg->count++;
 278 }
 279
 280 static int mall_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
 281                           void *cb_priv, struct netlink_ext_ack *extack)
 282 {
 283         struct cls_mall_head *head = rtnl_dereference(tp->root);
 284         struct tc_cls_matchall_offload cls_mall = {};
 285         struct tcf_block *block = tp->chain->block;
 286         int err;
 287
 288         if (tc_skip_hw(head->flags))
 289                 return 0;
 290
 291         cls_mall.rule = flow_rule_alloc(tcf_exts_num_actions(&head->exts));
 292         if (!cls_mall.rule)
 293                 return -ENOMEM;
 294
 295         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
 296         cls_mall.command = add ?
 297                 TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
 298         cls_mall.cookie = (unsigned long)head;
 299
 300         err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts);
 301         if (err) {
 302                 kfree(cls_mall.rule);
 303                 if (add && tc_skip_sw(head->flags)) {
 304                         NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
 305                         return err;
 306                 }
 307                 return 0;
 308         }
 309
 310         err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
 311         kfree(cls_mall.rule);
 312
 313         if (err) {
 314                 if (add && tc_skip_sw(head->flags))
 315                         return err;
 316                 return 0;
 317         }
 318
 319         tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
 320
 321         return 0;
 322 }
 323
 324 static void mall_stats_hw_filter(struct tcf_proto *tp,
 325                                  struct cls_mall_head *head,
 326                                  unsigned long cookie)
 327 {
 328         struct tc_cls_matchall_offload cls_mall = {};
 329         struct tcf_block *block = tp->chain->block;
 330
 331         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, NULL);
 332         cls_mall.command = TC_CLSMATCHALL_STATS;
 333         cls_mall.cookie = cookie;
 334
 335         tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
 336
 337         tcf_exts_stats_update(&head->exts, cls_mall.stats.bytes,
 338                               cls_mall.stats.pkts, cls_mall.stats.lastused);
 339 }
 340
 341 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
 342                      struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
 343 {
 344         struct tc_matchall_pcnt gpf = {};
 345         struct cls_mall_head *head = fh;
 346         struct nlattr *nest;
 347         int cpu;
 348
 349         if (!head)
 350                 return skb->len;
 351
 352         if (!tc_skip_hw(head->flags))
 353                 mall_stats_hw_filter(tp, head, (unsigned long)head);
 354
 355         t->tcm_handle = head->handle;
 356
 357         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 358         if (!nest)
 359                 goto nla_put_failure;
 360
 361         if (head->res.classid &&
 362             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 363                 goto nla_put_failure;
 364
 365         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 366                 goto nla_put_failure;
 367
 368         for_each_possible_cpu(cpu) {
 369                 struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
 370
 371                 gpf.rhit += pf->rhit;
 372         }
 373
 374         if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
 375                           sizeof(struct tc_matchall_pcnt),
 376                           &gpf, TCA_MATCHALL_PAD))
 377                 goto nla_put_failure;
 378
 379         if (tcf_exts_dump(skb, &head->exts))
 380                 goto nla_put_failure;
 381
 382         nla_nest_end(skb, nest);
 383
 384         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 385                 goto nla_put_failure;
 386
 387         return skb->len;
 388
 389 nla_put_failure:
 390         nla_nest_cancel(skb, nest);
 391         return -1;
 392 }
 393
 394 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
 395 {
 396         struct cls_mall_head *head = fh;
 397
 398         if (head && head->res.classid == classid)
 399                 head->res.class = cl;
 400 }
 401
 402 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 403         .kind           = "matchall",
 404         .classify       = mall_classify,
 405         .init           = mall_init,
 406         .destroy        = mall_destroy,
 407         .get            = mall_get,
 408         .change         = mall_change,
 409         .delete         = mall_delete,
 410         .walk           = mall_walk,
 411         .reoffload      = mall_reoffload,
 412         .dump           = mall_dump,
 413         .bind_class     = mall_bind_class,
 414         .owner          = THIS_MODULE,
 415 };
 416
 417 static int __init cls_mall_init(void)
 418 {
 419         return register_tcf_proto_ops(&cls_mall_ops);
 420 }
 421
 422 static void __exit cls_mall_exit(void)
 423 {
 424         unregister_tcf_proto_ops(&cls_mall_ops);
 425 }
 426
 427 module_init(cls_mall_init);
 428 module_exit(cls_mall_exit);
 429
 430 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 431 MODULE_DESCRIPTION("Match-all classifier");
 432 MODULE_LICENSE("GPL v2");