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         tcf_unbind_filter(tp, &head->res);
 112
 113         if (!tc_skip_hw(head->flags))
 114                 mall_destroy_hw_filter(tp, head, (unsigned long) head);
 115
 116         if (tcf_exts_get_net(&head->exts))
 117                 tcf_queue_work(&head->rwork, mall_destroy_work);
 118         else
 119                 __mall_destroy(head);
 120 }
 121
 122 static void *mall_get(struct tcf_proto *tp, u32 handle)
 123 {
 124         struct cls_mall_head *head = rtnl_dereference(tp->root);
 125
 126         if (head && head->handle == handle)
 127                 return head;
 128
 129         return NULL;
 130 }
 131
 132 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
 133         [TCA_MATCHALL_UNSPEC]           = { .type = NLA_UNSPEC },
 134         [TCA_MATCHALL_CLASSID]          = { .type = NLA_U32 },
 135 };
 136
 137 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
 138                           struct cls_mall_head *head,
 139                           unsigned long base, struct nlattr **tb,
 140                           struct nlattr *est, bool ovr)
 141 {
 142         int err;
 143
 144         err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr);
 145         if (err < 0)
 146                 return err;
 147
 148         if (tb[TCA_MATCHALL_CLASSID]) {
 149                 head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
 150                 tcf_bind_filter(tp, &head->res, base);
 151         }
 152         return 0;
 153 }
 154
 155 static int mall_change(struct net *net, struct sk_buff *in_skb,
 156                        struct tcf_proto *tp, unsigned long base,
 157                        u32 handle, struct nlattr **tca,
 158                        void **arg, bool ovr)
 159 {
 160         struct cls_mall_head *head = rtnl_dereference(tp->root);
 161         struct nlattr *tb[TCA_MATCHALL_MAX + 1];
 162         struct cls_mall_head *new;
 163         u32 flags = 0;
 164         int err;
 165
 166         if (!tca[TCA_OPTIONS])
 167                 return -EINVAL;
 168
 169         if (head)
 170                 return -EEXIST;
 171
 172         err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
 173                                mall_policy, NULL);
 174         if (err < 0)
 175                 return err;
 176
 177         if (tb[TCA_MATCHALL_FLAGS]) {
 178                 flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
 179                 if (!tc_flags_valid(flags))
 180                         return -EINVAL;
 181         }
 182
 183         new = kzalloc(sizeof(*new), GFP_KERNEL);
 184         if (!new)
 185                 return -ENOBUFS;
 186
 187         err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
 188         if (err)
 189                 goto err_exts_init;
 190
 191         if (!handle)
 192                 handle = 1;
 193         new->handle = handle;
 194         new->flags = flags;
 195
 196         err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
 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                 if (err)
 203                         goto err_replace_hw_filter;
 204         }
 205
 206         if (!tc_in_hw(new->flags))
 207                 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 208
 209         *arg = head;
 210         rcu_assign_pointer(tp->root, new);
 211         return 0;
 212
 213 err_replace_hw_filter:
 214 err_set_parms:
 215         tcf_exts_destroy(&new->exts);
 216 err_exts_init:
 217         kfree(new);
 218         return err;
 219 }
 220
 221 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last)
 222 {
 223         return -EOPNOTSUPP;
 224 }
 225
 226 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 227 {
 228         struct cls_mall_head *head = rtnl_dereference(tp->root);
 229
 230         if (arg->count < arg->skip)
 231                 goto skip;
 232         if (arg->fn(tp, head, arg) < 0)
 233                 arg->stop = 1;
 234 skip:
 235         arg->count++;
 236 }
 237
 238 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
 239                      struct sk_buff *skb, struct tcmsg *t)
 240 {
 241         struct cls_mall_head *head = fh;
 242         struct nlattr *nest;
 243
 244         if (!head)
 245                 return skb->len;
 246
 247         t->tcm_handle = head->handle;
 248
 249         nest = nla_nest_start(skb, TCA_OPTIONS);
 250         if (!nest)
 251                 goto nla_put_failure;
 252
 253         if (head->res.classid &&
 254             nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
 255                 goto nla_put_failure;
 256
 257         if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
 258                 goto nla_put_failure;
 259
 260         if (tcf_exts_dump(skb, &head->exts))
 261                 goto nla_put_failure;
 262
 263         nla_nest_end(skb, nest);
 264
 265         if (tcf_exts_dump_stats(skb, &head->exts) < 0)
 266                 goto nla_put_failure;
 267
 268         return skb->len;
 269
 270 nla_put_failure:
 271         nla_nest_cancel(skb, nest);
 272         return -1;
 273 }
 274
 275 static void mall_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
 276                             unsigned long base)
 277 {
 278         struct cls_mall_head *head = fh;
 279
 280         if (head && head->res.classid == classid) {
 281                 if (cl)
 282                         __tcf_bind_filter(q, &head->res, base);
 283                 else
 284                         __tcf_unbind_filter(q, &head->res);
 285         }
 286 }
 287
 288 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
 289         .kind           = "matchall",
 290         .classify       = mall_classify,
 291         .init           = mall_init,
 292         .destroy        = mall_destroy,
 293         .get            = mall_get,
 294         .change         = mall_change,
 295         .delete         = mall_delete,
 296         .walk           = mall_walk,
 297         .dump           = mall_dump,
 298         .bind_class     = mall_bind_class,
 299         .owner          = THIS_MODULE,
 300 };
 301
 302 static int __init cls_mall_init(void)
 303 {
 304         return register_tcf_proto_ops(&cls_mall_ops);
 305 }
 306
 307 static void __exit cls_mall_exit(void)
 308 {
 309         unregister_tcf_proto_ops(&cls_mall_ops);
 310 }
 311
 312 module_init(cls_mall_init);
 313 module_exit(cls_mall_exit);
 314
 315 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
 316 MODULE_DESCRIPTION("Match-all classifier");
 317 MODULE_LICENSE("GPL v2");