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         bool deleting;
  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 (unlikely(!head))
  33                 return -1;
  34
  35         if (tc_skip_sw(head->flags))
  36                 return -1;
  37
  38         *res = head->res;
  39         __this_cpu_inc(head->pf->rhit);
  40         return tcf_exts_exec(skb, &head->exts, res);
  41 }
  42
  43 static int mall_init(struct tcf_proto *tp)
  44 {
  45         return 0;
  46 }
  47
  48 static void __mall_destroy(struct cls_mall_head *head)
  49 {
  50         tcf_exts_destroy(&head->exts);
  51         tcf_exts_put_net(&head->exts);
  52         free_percpu(head->pf);
  53         kfree(head);
  54 }
  55
  56 static void mall_destroy_work(struct work_struct *work)
  57 {
  58         struct cls_mall_head *head = container_of(to_rcu_work(work),
  59                                                   struct cls_mall_head,
  60                                                   rwork);
  61         rtnl_lock();
  62         __mall_destroy(head);
  63         rtnl_unlock();
  64 }
  65
  66 static void mall_destroy_hw_filter(struct tcf_proto *tp,
  67                                    struct cls_mall_head *head,
  68                                    unsigned long cookie,
  69                                    struct netlink_ext_ack *extack)
  70 {
  71         struct tc_cls_matchall_offload cls_mall = {};
  72         struct tcf_block *block = tp->chain->block;
  73
  74         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  75         cls_mall.command = TC_CLSMATCHALL_DESTROY;
  76         cls_mall.cookie = cookie;
  77
  78         tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
  79         tcf_block_offload_dec(block, &head->flags);
  80 }
  81
  82 static int mall_replace_hw_filter(struct tcf_proto *tp,
  83                                   struct cls_mall_head *head,
  84                                   unsigned long cookie,
  85                                   struct netlink_ext_ack *extack)
  86 {
  87         struct tc_cls_matchall_offload cls_mall = {};
  88         struct tcf_block *block = tp->chain->block;
  89         bool skip_sw = tc_skip_sw(head->flags);
  90         int err;
  91
  92         cls_mall.rule = flow_rule_alloc(tcf_exts_num_actions(&head->exts));
  93         if (!cls_mall.rule)
  94                 return -ENOMEM;
  95
  96         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  97         cls_mall.command = TC_CLSMATCHALL_REPLACE;
  98         cls_mall.cookie = cookie;
  99
 100         err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts);
 101         if (err) {
 102                 kfree(cls_mall.rule);
 103                 mall_destroy_hw_filter(tp, head, cookie, NULL);
 104                 if (skip_sw)
 105                         NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
 106                 else
 107                         err = 0;
 108
 109                 return err;
 110         }
 111
 112         err = tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, skip_sw);
 113         kfree(cls_mall.rule);
 114
 115         if (err < 0) {
 116                 mall_destroy_hw_filter(tp, head, cookie, NULL);
 117                 return err;
 118         } else if (err > 0) {
 119                 head->in_hw_count = err;
 120                 tcf_block_offload_inc(block, &head->flags);
 121         }
 122
 123         if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
 124                 return -EINVAL;
 125
 126         return 0;
 127 }
 128
 129 static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
 130                          struct netlink_ext_ack *extack)
 131 {
 132         struct cls_mall_head *head = rtnl_dereference(tp->root);
 133
 134         if (!head)
 135                 return;
 136
 137         tcf_unbind_filter(tp, &head->res);
 138
 139         if (!tc_skip_hw(head->flags))
 140                 mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
 141
 142         if (tcf_exts_get_net(&head->exts))
 143                 tcf_queue_work(&head->rwork, mall_destroy_work);
 144         else
 145                 __mall_destroy(head);
 146 }
 147
 148 static void *mall_get(struct tcf_proto *tp, u32 handle)
 149 {
 150         struct cls_mall_head *head = rtnl_dereference(tp->root);
 151
 152         if (head && head->handle == handle)
 153                 return head;
 154
 155         return NULL;
 156 }
 157
 158 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 159         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 160         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 161 };
 162
 163 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 164                           struct cls_mall_head *head,
 165                           unsigned long base, struct nlattr **tb,
 166                           struct nlattr *est, bool ovr,
 167                           struct netlink_ext_ack *extack)
 168 {
 169         int err;
 170
 171         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, true,
 172                                 extack);
 173         if (err < 0)
 174                 return err;
 175
 176         if (tb[TCA_MATCHALL_CLASSID]) {
 177                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 178                 tcf_bind_filter(tp, &head->res, base);
 179         }
 180         return 0;
 181 }
 182
 183 static int mall_change(struct net *net, struct sk_buff *in_skb,
 184                        struct tcf_proto *tp, unsigned long base,
 185                        u32 handle, struct nlattr **tca,
 186                        void **arg, bool ovr, bool rtnl_held,
 187                        struct netlink_ext_ack *extack)
 188 {
 189         struct cls_mall_head *head = rtnl_dereference(tp->root);
 190         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 191         struct cls_mall_head *new;
 192         u32 flags = 0;
 193         int err;
 194
 195         if (!tca[TCA_OPTIONS])
 196                 return -EINVAL;
 197
 198         if (head)
 199                 return -EEXIST;
 200
 201         err = nla_parse_nested_deprecated(tb, TCA_MATCHALL_MAX,
 202                                           tca[TCA_OPTIONS], mall_policy, NULL);
 203         if (err < 0)
 204                 return err;
 205
 206         if (tb[TCA_MATCHALL_FLAGS]) {
 207                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 208                 if (!tc_flags_valid(flags))
 209                         return -EINVAL;
 210         }
 211
 212         new = kzalloc(sizeof(*new), GFP_KERNEL);
 213         if (!new)
 214                 return -ENOBUFS;
 215
 216         err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
 217         if (err)
 218                 goto err_exts_init;
 219
 220         if (!handle)
 221                 handle = 1;
 222         new->handle = handle;
 223         new->flags = flags;
 224         new->pf = alloc_percpu(struct tc_matchall_pcnt);
 225         if (!new->pf) {
 226                 err = -ENOMEM;
 227                 goto err_alloc_percpu;
 228         }
 229
 230         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
 231                              extack);
 232         if (err)
 233                 goto err_set_parms;
 234
 235         if (!tc_skip_hw(new->flags)) {
 236                 err = mall_replace_hw_filter(tp, new, (unsigned long)new,
 237                                              extack);
 238                 if (err)
 239                         goto err_replace_hw_filter;
 240         }
 241
 242         if (!tc_in_hw(new->flags))
 243                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 244
 245         *arg = head;
 246         rcu_assign_pointer(tp->root, new);
 247         return 0;
 248
 249 err_replace_hw_filter:
 250 err_set_parms:
 251         free_percpu(new->pf);
 252 err_alloc_percpu:
 253         tcf_exts_destroy(&new->exts);
 254 err_exts_init:
 255         kfree(new);
 256         return err;
 257 }
 258
 259 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
 260                        bool rtnl_held, struct netlink_ext_ack *extack)
 261 {
 262         struct cls_mall_head *head = rtnl_dereference(tp->root);
 263
 264         head->deleting = true;
 265         *last = true;
 266         return 0;
 267 }
 268
 269 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 270                       bool rtnl_held)
 271 {
 272         struct cls_mall_head *head = rtnl_dereference(tp->root);
 273
 274         if (arg->count < arg->skip)
 275                 goto skip;
 276
 277         if (!head || head->deleting)
 278                 return;
 279         if (arg->fn(tp, head, arg) < 0)
 280                 arg->stop = 1;
 281 skip:
 282         arg->count++;
 283 }
 284
 285 static int mall_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
 286                           void *cb_priv, struct netlink_ext_ack *extack)
 287 {
 288         struct cls_mall_head *head = rtnl_dereference(tp->root);
 289         struct tc_cls_matchall_offload cls_mall = {};
 290         struct tcf_block *block = tp->chain->block;
 291         int err;
 292
 293         if (tc_skip_hw(head->flags))
 294                 return 0;
 295
 296         cls_mall.rule = flow_rule_alloc(tcf_exts_num_actions(&head->exts));
 297         if (!cls_mall.rule)
 298                 return -ENOMEM;
 299
 300         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
 301         cls_mall.command = add ?
 302                 TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
 303         cls_mall.cookie = (unsigned long)head;
 304
 305         err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts);
 306         if (err) {
 307                 kfree(cls_mall.rule);
 308                 if (add && tc_skip_sw(head->flags)) {
 309                         NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
 310                         return err;
 311                 }
 312                 return 0;
 313         }
 314
 315         err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
 316         kfree(cls_mall.rule);
 317
 318         if (err) {
 319                 if (add && tc_skip_sw(head->flags))
 320                         return err;
 321                 return 0;
 322         }
 323
 324         tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
 325
 326         return 0;
 327 }
 328
 329 static void mall_stats_hw_filter(struct tcf_proto *tp,
 330                                  struct cls_mall_head *head,
 331                                  unsigned long cookie)
 332 {
 333         struct tc_cls_matchall_offload cls_mall = {};
 334         struct tcf_block *block = tp->chain->block;
 335
 336         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, NULL);
 337         cls_mall.command = TC_CLSMATCHALL_STATS;
 338         cls_mall.cookie = cookie;
 339
 340         tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
 341
 342         tcf_exts_stats_update(&head->exts, cls_mall.stats.bytes,
 343                               cls_mall.stats.pkts, cls_mall.stats.lastused);
 344 }
 345
 346 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
 347                      struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
 348 {
 349         struct tc_matchall_pcnt gpf = {};
 350         struct cls_mall_head *head = fh;
 351         struct nlattr *nest;
 352         int cpu;
 353
 354         if (!head)
 355                 return skb->len;
 356
 357         if (!tc_skip_hw(head->flags))
 358                 mall_stats_hw_filter(tp, head, (unsigned long)head);
 359
 360         t->tcm_handle = head->handle;
 361
 362         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 363         if (!nest)
 364                 goto nla_put_failure;
 365
 366         if (head->res.classid &&
 367             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 368                 goto nla_put_failure;
 369
 370         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 371                 goto nla_put_failure;
 372
 373         for_each_possible_cpu(cpu) {
 374                 struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
 375
 376                 gpf.rhit += pf->rhit;
 377         }
 378
 379         if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
 380                           sizeof(struct tc_matchall_pcnt),
 381                           &gpf, TCA_MATCHALL_PAD))
 382                 goto nla_put_failure;
 383
 384         if (tcf_exts_dump(skb, &head->exts))
 385                 goto nla_put_failure;
 386
 387         nla_nest_end(skb, nest);
 388
 389         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 390                 goto nla_put_failure;
 391
 392         return skb->len;
 393
 394 nla_put_failure:
 395         nla_nest_cancel(skb, nest);
 396         return -1;
 397 }
 398
 399 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
 400 {
 401         struct cls_mall_head *head = fh;
 402
 403         if (head && head->res.classid == classid)
 404                 head->res.class = cl;
 405 }
 406
 407 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 408         .kind           = "matchall",
 409         .classify       = mall_classify,
 410         .init           = mall_init,
 411         .destroy        = mall_destroy,
 412         .get            = mall_get,
 413         .change         = mall_change,
 414         .delete         = mall_delete,
 415         .walk           = mall_walk,
 416         .reoffload      = mall_reoffload,
 417         .dump           = mall_dump,
 418         .bind_class     = mall_bind_class,
 419         .owner          = THIS_MODULE,
 420 };
 421
 422 static int __init cls_mall_init(void)
 423 {
 424         return register_tcf_proto_ops(&cls_mall_ops);
 425 }
 426
 427 static void __exit cls_mall_exit(void)
 428 {
 429         unregister_tcf_proto_ops(&cls_mall_ops);
 430 }
 431
 432 module_init(cls_mall_init);
 433 module_exit(cls_mall_exit);
 434
 435 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 436 MODULE_DESCRIPTION("Match-all classifier");
 437 MODULE_LICENSE("GPL v2");