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