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 (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         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  93         cls_mall.command = TC_CLSMATCHALL_REPLACE;
  94         cls_mall.exts = &head->exts;
  95         cls_mall.cookie = cookie;
  96
  97         err = tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, skip_sw);
  98         if (err < 0) {
  99                 mall_destroy_hw_filter(tp, head, cookie, NULL);
 100                 return err;
 101         } else if (err > 0) {
 102                 head->in_hw_count = err;
 103                 tcf_block_offload_inc(block, &head->flags);
 104         }
 105
 106         if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
 107                 return -EINVAL;
 108
 109         return 0;
 110 }
 111
 112 static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
 113                          struct netlink_ext_ack *extack)
 114 {
 115         struct cls_mall_head *head = rtnl_dereference(tp->root);
 116
 117         if (!head)
 118                 return;
 119
 120         tcf_unbind_filter(tp, &head->res);
 121
 122         if (!tc_skip_hw(head->flags))
 123                 mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
 124
 125         if (tcf_exts_get_net(&head->exts))
 126                 tcf_queue_work(&head->rwork, mall_destroy_work);
 127         else
 128                 __mall_destroy(head);
 129 }
 130
 131 static void *mall_get(struct tcf_proto *tp, u32 handle)
 132 {
 133         struct cls_mall_head *head = rtnl_dereference(tp->root);
 134
 135         if (head && head->handle == handle)
 136                 return head;
 137
 138         return NULL;
 139 }
 140
 141 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 142         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 143         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 144 };
 145
 146 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 147                           struct cls_mall_head *head,
 148                           unsigned long base, struct nlattr **tb,
 149                           struct nlattr *est, bool ovr,
 150                           struct netlink_ext_ack *extack)
 151 {
 152         int err;
 153
 154         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, true,
 155                                 extack);
 156         if (err < 0)
 157                 return err;
 158
 159         if (tb[TCA_MATCHALL_CLASSID]) {
 160                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 161                 tcf_bind_filter(tp, &head->res, base);
 162         }
 163         return 0;
 164 }
 165
 166 static int mall_change(struct net *net, struct sk_buff *in_skb,
 167                        struct tcf_proto *tp, unsigned long base,
 168                        u32 handle, struct nlattr **tca,
 169                        void **arg, bool ovr, bool rtnl_held,
 170                        struct netlink_ext_ack *extack)
 171 {
 172         struct cls_mall_head *head = rtnl_dereference(tp->root);
 173         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 174         struct cls_mall_head *new;
 175         u32 flags = 0;
 176         int err;
 177
 178         if (!tca[TCA_OPTIONS])
 179                 return -EINVAL;
 180
 181         if (head)
 182                 return -EEXIST;
 183
 184         err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
 185                                mall_policy, NULL);
 186         if (err < 0)
 187                 return err;
 188
 189         if (tb[TCA_MATCHALL_FLAGS]) {
 190                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 191                 if (!tc_flags_valid(flags))
 192                         return -EINVAL;
 193         }
 194
 195         new = kzalloc(sizeof(*new), GFP_KERNEL);
 196         if (!new)
 197                 return -ENOBUFS;
 198
 199         err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
 200         if (err)
 201                 goto err_exts_init;
 202
 203         if (!handle)
 204                 handle = 1;
 205         new->handle = handle;
 206         new->flags = flags;
 207         new->pf = alloc_percpu(struct tc_matchall_pcnt);
 208         if (!new->pf) {
 209                 err = -ENOMEM;
 210                 goto err_alloc_percpu;
 211         }
 212
 213         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
 214                              extack);
 215         if (err)
 216                 goto err_set_parms;
 217
 218         if (!tc_skip_hw(new->flags)) {
 219                 err = mall_replace_hw_filter(tp, new, (unsigned long)new,
 220                                              extack);
 221                 if (err)
 222                         goto err_replace_hw_filter;
 223         }
 224
 225         if (!tc_in_hw(new->flags))
 226                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 227
 228         *arg = head;
 229         rcu_assign_pointer(tp->root, new);
 230         return 0;
 231
 232 err_replace_hw_filter:
 233 err_set_parms:
 234         free_percpu(new->pf);
 235 err_alloc_percpu:
 236         tcf_exts_destroy(&new->exts);
 237 err_exts_init:
 238         kfree(new);
 239         return err;
 240 }
 241
 242 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
 243                        bool rtnl_held, struct netlink_ext_ack *extack)
 244 {
 245         return -EOPNOTSUPP;
 246 }
 247
 248 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 249                       bool rtnl_held)
 250 {
 251         struct cls_mall_head *head = rtnl_dereference(tp->root);
 252
 253         if (arg->count < arg->skip)
 254                 goto skip;
 255
 256         if (!head)
 257                 return;
 258         if (arg->fn(tp, head, arg) < 0)
 259                 arg->stop = 1;
 260 skip:
 261         arg->count++;
 262 }
 263
 264 static int mall_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
 265                           void *cb_priv, struct netlink_ext_ack *extack)
 266 {
 267         struct cls_mall_head *head = rtnl_dereference(tp->root);
 268         struct tc_cls_matchall_offload cls_mall = {};
 269         struct tcf_block *block = tp->chain->block;
 270         int err;
 271
 272         if (tc_skip_hw(head->flags))
 273                 return 0;
 274
 275         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
 276         cls_mall.command = add ?
 277                 TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
 278         cls_mall.exts = &head->exts;
 279         cls_mall.cookie = (unsigned long)head;
 280
 281         err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
 282         if (err) {
 283                 if (add && tc_skip_sw(head->flags))
 284                         return err;
 285                 return 0;
 286         }
 287
 288         tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
 289
 290         return 0;
 291 }
 292
 293 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
 294                      struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
 295 {
 296         struct tc_matchall_pcnt gpf = {};
 297         struct cls_mall_head *head = fh;
 298         struct nlattr *nest;
 299         int cpu;
 300
 301         if (!head)
 302                 return skb->len;
 303
 304         t->tcm_handle = head->handle;
 305
 306         nest = nla_nest_start(skb, TCA_OPTIONS);
 307         if (!nest)
 308                 goto nla_put_failure;
 309
 310         if (head->res.classid &&
 311             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 312                 goto nla_put_failure;
 313
 314         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 315                 goto nla_put_failure;
 316
 317         for_each_possible_cpu(cpu) {
 318                 struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
 319
 320                 gpf.rhit += pf->rhit;
 321         }
 322
 323         if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
 324                           sizeof(struct tc_matchall_pcnt),
 325                           &gpf, TCA_MATCHALL_PAD))
 326                 goto nla_put_failure;
 327
 328         if (tcf_exts_dump(skb, &head->exts))
 329                 goto nla_put_failure;
 330
 331         nla_nest_end(skb, nest);
 332
 333         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 334                 goto nla_put_failure;
 335
 336         return skb->len;
 337
 338 nla_put_failure:
 339         nla_nest_cancel(skb, nest);
 340         return -1;
 341 }
 342
 343 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
 344 {
 345         struct cls_mall_head *head = fh;
 346
 347         if (head && head->res.classid == classid)
 348                 head->res.class = cl;
 349 }
 350
 351 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 352         .kind           = "matchall",
 353         .classify       = mall_classify,
 354         .init           = mall_init,
 355         .destroy        = mall_destroy,
 356         .get            = mall_get,
 357         .change         = mall_change,
 358         .delete         = mall_delete,
 359         .walk           = mall_walk,
 360         .reoffload      = mall_reoffload,
 361         .dump           = mall_dump,
 362         .bind_class     = mall_bind_class,
 363         .owner          = THIS_MODULE,
 364 };
 365
 366 static int __init cls_mall_init(void)
 367 {
 368         return register_tcf_proto_ops(&cls_mall_ops);
 369 }
 370
 371 static void __exit cls_mall_exit(void)
 372 {
 373         unregister_tcf_proto_ops(&cls_mall_ops);
 374 }
 375
 376 module_init(cls_mall_init);
 377 module_exit(cls_mall_exit);
 378
 379 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 380 MODULE_DESCRIPTION("Match-all classifier");
 381 MODULE_LICENSE("GPL v2");