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         unsigned int in_hw_count;
  25         struct rcu_work rwork;
  26 };
  27
  28 static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
  29                          struct tcf_result *res)
  30 {
  31         struct cls_mall_head *head = rcu_dereference_bh(tp->root);
  32
  33         if (tc_skip_sw(head->flags))
  34                 return -1;
  35
  36         *res = head->res;
  37         return tcf_exts_exec(skb, &head->exts, res);
  38 }
  39
  40 static int mall_init(struct tcf_proto *tp)
  41 {
  42         return 0;
  43 }
  44
  45 static void __mall_destroy(struct cls_mall_head *head)
  46 {
  47         tcf_exts_destroy(&head->exts);
  48         tcf_exts_put_net(&head->exts);
  49         kfree(head);
  50 }
  51
  52 static void mall_destroy_work(struct work_struct *work)
  53 {
  54         struct cls_mall_head *head = container_of(to_rcu_work(work),
  55                                                   struct cls_mall_head,
  56                                                   rwork);
  57         rtnl_lock();
  58         __mall_destroy(head);
  59         rtnl_unlock();
  60 }
  61
  62 static void mall_destroy_hw_filter(struct tcf_proto *tp,
  63                                    struct cls_mall_head *head,
  64                                    unsigned long cookie,
  65                                    struct netlink_ext_ack *extack)
  66 {
  67         struct tc_cls_matchall_offload cls_mall = {};
  68         struct tcf_block *block = tp->chain->block;
  69
  70         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  71         cls_mall.command = TC_CLSMATCHALL_DESTROY;
  72         cls_mall.cookie = cookie;
  73
  74         tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL, &cls_mall, false);
  75         tcf_block_offload_dec(block, &head->flags);
  76 }
  77
  78 static int mall_replace_hw_filter(struct tcf_proto *tp,
  79                                   struct cls_mall_head *head,
  80                                   unsigned long cookie,
  81                                   struct netlink_ext_ack *extack)
  82 {
  83         struct tc_cls_matchall_offload cls_mall = {};
  84         struct tcf_block *block = tp->chain->block;
  85         bool skip_sw = tc_skip_sw(head->flags);
  86         int err;
  87
  88         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
  89         cls_mall.command = TC_CLSMATCHALL_REPLACE;
  90         cls_mall.exts = &head->exts;
  91         cls_mall.cookie = cookie;
  92
  93         err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL,
  94                                &cls_mall, skip_sw);
  95         if (err < 0) {
  96                 mall_destroy_hw_filter(tp, head, cookie, NULL);
  97                 return err;
  98         } else if (err > 0) {
  99                 head->in_hw_count = err;
 100                 tcf_block_offload_inc(block, &head->flags);
 101         }
 102
 103         if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
 104                 return -EINVAL;
 105
 106         return 0;
 107 }
 108
 109 static void mall_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
 110 {
 111         struct cls_mall_head *head = rtnl_dereference(tp->root);
 112
 113         if (!head)
 114                 return;
 115
 116         if (!tc_skip_hw(head->flags))
 117                 mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
 118
 119         if (tcf_exts_get_net(&head->exts))
 120                 tcf_queue_work(&head->rwork, mall_destroy_work);
 121         else
 122                 __mall_destroy(head);
 123 }
 124
 125 static void *mall_get(struct tcf_proto *tp, u32 handle)
 126 {
 127         return NULL;
 128 }
 129
 130 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 131         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 132         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 133 };
 134
 135 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 136                           struct cls_mall_head *head,
 137                           unsigned long base, struct nlattr **tb,
 138                           struct nlattr *est, bool ovr,
 139                           struct netlink_ext_ack *extack)
 140 {
 141         int err;
 142
 143         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, extack);
 144         if (err < 0)
 145                 return err;
 146
 147         if (tb[TCA_MATCHALL_CLASSID]) {
 148                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 149                 tcf_bind_filter(tp, &head->res, base);
 150         }
 151         return 0;
 152 }
 153
 154 static int mall_change(struct net *net, struct sk_buff *in_skb,
 155                        struct tcf_proto *tp, unsigned long base,
 156                        u32 handle, struct nlattr **tca,
 157                        void **arg, bool ovr, struct netlink_ext_ack *extack)
 158 {
 159         struct cls_mall_head *head = rtnl_dereference(tp->root);
 160         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 161         struct cls_mall_head *new;
 162         u32 flags = 0;
 163         int err;
 164
 165         if (!tca[TCA_OPTIONS])
 166                 return -EINVAL;
 167
 168         if (head)
 169                 return -EEXIST;
 170
 171         err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
 172                                mall_policy, NULL);
 173         if (err < 0)
 174                 return err;
 175
 176         if (tb[TCA_MATCHALL_FLAGS]) {
 177                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 178                 if (!tc_flags_valid(flags))
 179                         return -EINVAL;
 180         }
 181
 182         new = kzalloc(sizeof(*new), GFP_KERNEL);
 183         if (!new)
 184                 return -ENOBUFS;
 185
 186         err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
 187         if (err)
 188                 goto err_exts_init;
 189
 190         if (!handle)
 191                 handle = 1;
 192         new->handle = handle;
 193         new->flags = flags;
 194
 195         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
 196                              extack);
 197         if (err)
 198                 goto err_set_parms;
 199
 200         if (!tc_skip_hw(new->flags)) {
 201                 err = mall_replace_hw_filter(tp, new, (unsigned long)new,
 202                                              extack);
 203                 if (err)
 204                         goto err_replace_hw_filter;
 205         }
 206
 207         if (!tc_in_hw(new->flags))
 208                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 209
 210         *arg = head;
 211         rcu_assign_pointer(tp->root, new);
 212         return 0;
 213
 214 err_replace_hw_filter:
 215 err_set_parms:
 216         tcf_exts_destroy(&new->exts);
 217 err_exts_init:
 218         kfree(new);
 219         return err;
 220 }
 221
 222 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
 223                        struct netlink_ext_ack *extack)
 224 {
 225         return -EOPNOTSUPP;
 226 }
 227
 228 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 229 {
 230         struct cls_mall_head *head = rtnl_dereference(tp->root);
 231
 232         if (arg->count < arg->skip)
 233                 goto skip;
 234         if (arg->fn(tp, head, arg) < 0)
 235                 arg->stop = 1;
 236 skip:
 237         arg->count++;
 238 }
 239
 240 static int mall_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
 241                           void *cb_priv, struct netlink_ext_ack *extack)
 242 {
 243         struct cls_mall_head *head = rtnl_dereference(tp->root);
 244         struct tc_cls_matchall_offload cls_mall = {};
 245         struct tcf_block *block = tp->chain->block;
 246         int err;
 247
 248         if (tc_skip_hw(head->flags))
 249                 return 0;
 250
 251         tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
 252         cls_mall.command = add ?
 253                 TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
 254         cls_mall.exts = &head->exts;
 255         cls_mall.cookie = (unsigned long)head;
 256
 257         err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
 258         if (err) {
 259                 if (add && tc_skip_sw(head->flags))
 260                         return err;
 261                 return 0;
 262         }
 263
 264         tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
 265
 266         return 0;
 267 }
 268
 269 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
 270                      struct sk_buff *skb, struct tcmsg *t)
 271 {
 272         struct cls_mall_head *head = fh;
 273         struct nlattr *nest;
 274
 275         if (!head)
 276                 return skb->len;
 277
 278         t->tcm_handle = head->handle;
 279
 280         nest = nla_nest_start(skb, TCA_OPTIONS);
 281         if (!nest)
 282                 goto nla_put_failure;
 283
 284         if (head->res.classid &&
 285             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 286                 goto nla_put_failure;
 287
 288         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 289                 goto nla_put_failure;
 290
 291         if (tcf_exts_dump(skb, &head->exts))
 292                 goto nla_put_failure;
 293
 294         nla_nest_end(skb, nest);
 295
 296         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 297                 goto nla_put_failure;
 298
 299         return skb->len;
 300
 301 nla_put_failure:
 302         nla_nest_cancel(skb, nest);
 303         return -1;
 304 }
 305
 306 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
 307 {
 308         struct cls_mall_head *head = fh;
 309
 310         if (head && head->res.classid == classid)
 311                 head->res.class = cl;
 312 }
 313
 314 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 315         .kind           = "matchall",
 316         .classify       = mall_classify,
 317         .init           = mall_init,
 318         .destroy        = mall_destroy,
 319         .get            = mall_get,
 320         .change         = mall_change,
 321         .delete         = mall_delete,
 322         .walk           = mall_walk,
 323         .reoffload      = mall_reoffload,
 324         .dump           = mall_dump,
 325         .bind_class     = mall_bind_class,
 326         .owner          = THIS_MODULE,
 327 };
 328
 329 static int __init cls_mall_init(void)
 330 {
 331         return register_tcf_proto_ops(&cls_mall_ops);
 332 }
 333
 334 static void __exit cls_mall_exit(void)
 335 {
 336         unregister_tcf_proto_ops(&cls_mall_ops);
 337 }
 338
 339 module_init(cls_mall_init);
 340 module_exit(cls_mall_exit);
 341
 342 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 343 MODULE_DESCRIPTION("Match-all classifier");
 344 MODULE_LICENSE("GPL v2");