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