net/netfilter/nft_set_rbtree.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
   4  *
   5  * Development of this code funded by Astaro AG (http://www.astaro.com/)
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11 #include <linux/list.h>
  12 #include <linux/rbtree.h>
  13 #include <linux/netlink.h>
  14 #include <linux/netfilter.h>
  15 #include <linux/netfilter/nf_tables.h>
  16 #include <net/netfilter/nf_tables_core.h>
  17
  18 struct nft_rbtree {
  19         struct rb_root          root;
  20         rwlock_t                lock;
  21         seqcount_rwlock_t       count;
  22         struct delayed_work     gc_work;
  23 };
  24
  25 struct nft_rbtree_elem {
  26         struct rb_node          node;
  27         struct nft_set_ext      ext;
  28 };
  29
  30 static bool nft_rbtree_interval_end(const struct nft_rbtree_elem *rbe)
  31 {
  32         return nft_set_ext_exists(&rbe->ext, NFT_SET_EXT_FLAGS) &&
  33                (*nft_set_ext_flags(&rbe->ext) & NFT_SET_ELEM_INTERVAL_END);
  34 }
  35
  36 static bool nft_rbtree_interval_start(const struct nft_rbtree_elem *rbe)
  37 {
  38         return !nft_rbtree_interval_end(rbe);
  39 }
  40
  41 static int nft_rbtree_cmp(const struct nft_set *set,
  42                           const struct nft_rbtree_elem *e1,
  43                           const struct nft_rbtree_elem *e2)
  44 {
  45         return memcmp(nft_set_ext_key(&e1->ext), nft_set_ext_key(&e2->ext),
  46                       set->klen);
  47 }
  48
  49 static bool __nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
  50                                 const u32 *key, const struct nft_set_ext **ext,
  51                                 unsigned int seq)
  52 {
  53         struct nft_rbtree *priv = nft_set_priv(set);
  54         const struct nft_rbtree_elem *rbe, *interval = NULL;
  55         u8 genmask = nft_genmask_cur(net);
  56         const struct rb_node *parent;
  57         int d;
  58
  59         parent = rcu_dereference_raw(priv->root.rb_node);
  60         while (parent != NULL) {
  61                 if (read_seqcount_retry(&priv->count, seq))
  62                         return false;
  63
  64                 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
  65
  66                 d = memcmp(nft_set_ext_key(&rbe->ext), key, set->klen);
  67                 if (d < 0) {
  68                         parent = rcu_dereference_raw(parent->rb_left);
  69                         if (interval &&
  70                             !nft_rbtree_cmp(set, rbe, interval) &&
  71                             nft_rbtree_interval_end(rbe) &&
  72                             nft_rbtree_interval_start(interval))
  73                                 continue;
  74                         interval = rbe;
  75                 } else if (d > 0)
  76                         parent = rcu_dereference_raw(parent->rb_right);
  77                 else {
  78                         if (!nft_set_elem_active(&rbe->ext, genmask)) {
  79                                 parent = rcu_dereference_raw(parent->rb_left);
  80                                 continue;
  81                         }
  82
  83                         if (nft_set_elem_expired(&rbe->ext))
  84                                 return false;
  85
  86                         if (nft_rbtree_interval_end(rbe)) {
  87                                 if (nft_set_is_anonymous(set))
  88                                         return false;
  89                                 parent = rcu_dereference_raw(parent->rb_left);
  90                                 interval = NULL;
  91                                 continue;
  92                         }
  93
  94                         *ext = &rbe->ext;
  95                         return true;
  96                 }
  97         }
  98
  99         if (set->flags & NFT_SET_INTERVAL && interval != NULL &&
 100             nft_set_elem_active(&interval->ext, genmask) &&
 101             !nft_set_elem_expired(&interval->ext) &&
 102             nft_rbtree_interval_start(interval)) {
 103                 *ext = &interval->ext;
 104                 return true;
 105         }
 106
 107         return false;
 108 }
 109
 110 INDIRECT_CALLABLE_SCOPE
 111 bool nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
 112                        const u32 *key, const struct nft_set_ext **ext)
 113 {
 114         struct nft_rbtree *priv = nft_set_priv(set);
 115         unsigned int seq = read_seqcount_begin(&priv->count);
 116         bool ret;
 117
 118         ret = __nft_rbtree_lookup(net, set, key, ext, seq);
 119         if (ret || !read_seqcount_retry(&priv->count, seq))
 120                 return ret;
 121
 122         read_lock_bh(&priv->lock);
 123         seq = read_seqcount_begin(&priv->count);
 124         ret = __nft_rbtree_lookup(net, set, key, ext, seq);
 125         read_unlock_bh(&priv->lock);
 126
 127         return ret;
 128 }
 129
 130 static bool __nft_rbtree_get(const struct net *net, const struct nft_set *set,
 131                              const u32 *key, struct nft_rbtree_elem **elem,
 132                              unsigned int seq, unsigned int flags, u8 genmask)
 133 {
 134         struct nft_rbtree_elem *rbe, *interval = NULL;
 135         struct nft_rbtree *priv = nft_set_priv(set);
 136         const struct rb_node *parent;
 137         const void *this;
 138         int d;
 139
 140         parent = rcu_dereference_raw(priv->root.rb_node);
 141         while (parent != NULL) {
 142                 if (read_seqcount_retry(&priv->count, seq))
 143                         return false;
 144
 145                 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
 146
 147                 this = nft_set_ext_key(&rbe->ext);
 148                 d = memcmp(this, key, set->klen);
 149                 if (d < 0) {
 150                         parent = rcu_dereference_raw(parent->rb_left);
 151                         if (!(flags & NFT_SET_ELEM_INTERVAL_END))
 152                                 interval = rbe;
 153                 } else if (d > 0) {
 154                         parent = rcu_dereference_raw(parent->rb_right);
 155                         if (flags & NFT_SET_ELEM_INTERVAL_END)
 156                                 interval = rbe;
 157                 } else {
 158                         if (!nft_set_elem_active(&rbe->ext, genmask)) {
 159                                 parent = rcu_dereference_raw(parent->rb_left);
 160                                 continue;
 161                         }
 162
 163                         if (nft_set_elem_expired(&rbe->ext))
 164                                 return false;
 165
 166                         if (!nft_set_ext_exists(&rbe->ext, NFT_SET_EXT_FLAGS) ||
 167                             (*nft_set_ext_flags(&rbe->ext) & NFT_SET_ELEM_INTERVAL_END) ==
 168                             (flags & NFT_SET_ELEM_INTERVAL_END)) {
 169                                 *elem = rbe;
 170                                 return true;
 171                         }
 172
 173                         if (nft_rbtree_interval_end(rbe))
 174                                 interval = NULL;
 175
 176                         parent = rcu_dereference_raw(parent->rb_left);
 177                 }
 178         }
 179
 180         if (set->flags & NFT_SET_INTERVAL && interval != NULL &&
 181             nft_set_elem_active(&interval->ext, genmask) &&
 182             !nft_set_elem_expired(&interval->ext) &&
 183             ((!nft_rbtree_interval_end(interval) &&
 184               !(flags & NFT_SET_ELEM_INTERVAL_END)) ||
 185              (nft_rbtree_interval_end(interval) &&
 186               (flags & NFT_SET_ELEM_INTERVAL_END)))) {
 187                 *elem = interval;
 188                 return true;
 189         }
 190
 191         return false;
 192 }
 193
 194 static void *nft_rbtree_get(const struct net *net, const struct nft_set *set,
 195                             const struct nft_set_elem *elem, unsigned int flags)
 196 {
 197         struct nft_rbtree *priv = nft_set_priv(set);
 198         unsigned int seq = read_seqcount_begin(&priv->count);
 199         struct nft_rbtree_elem *rbe = ERR_PTR(-ENOENT);
 200         const u32 *key = (const u32 *)&elem->key.val;
 201         u8 genmask = nft_genmask_cur(net);
 202         bool ret;
 203
 204         ret = __nft_rbtree_get(net, set, key, &rbe, seq, flags, genmask);
 205         if (ret || !read_seqcount_retry(&priv->count, seq))
 206                 return rbe;
 207
 208         read_lock_bh(&priv->lock);
 209         seq = read_seqcount_begin(&priv->count);
 210         ret = __nft_rbtree_get(net, set, key, &rbe, seq, flags, genmask);
 211         if (!ret)
 212                 rbe = ERR_PTR(-ENOENT);
 213         read_unlock_bh(&priv->lock);
 214
 215         return rbe;
 216 }
 217
 218 static int nft_rbtree_gc_elem(const struct nft_set *__set,
 219                               struct nft_rbtree *priv,
 220                               struct nft_rbtree_elem *rbe)
 221 {
 222         struct nft_set *set = (struct nft_set *)__set;
 223         struct rb_node *prev = rb_prev(&rbe->node);
 224         struct nft_rbtree_elem *rbe_prev = NULL;
 225         struct nft_set_gc_batch *gcb;
 226
 227         gcb = nft_set_gc_batch_check(set, NULL, GFP_ATOMIC);
 228         if (!gcb)
 229                 return -ENOMEM;
 230
 231         /* search for expired end interval coming before this element. */
 232         while (prev) {
 233                 rbe_prev = rb_entry(prev, struct nft_rbtree_elem, node);
 234                 if (nft_rbtree_interval_end(rbe_prev))
 235                         break;
 236
 237                 prev = rb_prev(prev);
 238         }
 239
 240         if (rbe_prev) {
 241                 rb_erase(&rbe_prev->node, &priv->root);
 242                 atomic_dec(&set->nelems);
 243         }
 244
 245         rb_erase(&rbe->node, &priv->root);
 246         atomic_dec(&set->nelems);
 247
 248         nft_set_gc_batch_add(gcb, rbe);
 249         nft_set_gc_batch_complete(gcb);
 250
 251         return 0;
 252 }
 253
 254 static bool nft_rbtree_update_first(const struct nft_set *set,
 255                                     struct nft_rbtree_elem *rbe,
 256                                     struct rb_node *first)
 257 {
 258         struct nft_rbtree_elem *first_elem;
 259
 260         first_elem = rb_entry(first, struct nft_rbtree_elem, node);
 261         /* this element is closest to where the new element is to be inserted:
 262          * update the first element for the node list path.
 263          */
 264         if (nft_rbtree_cmp(set, rbe, first_elem) < 0)
 265                 return true;
 266
 267         return false;
 268 }
 269
 270 static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 271                                struct nft_rbtree_elem *new,
 272                                struct nft_set_ext **ext)
 273 {
 274         struct nft_rbtree_elem *rbe, *rbe_le = NULL, *rbe_ge = NULL;
 275         struct rb_node *node, *next, *parent, **p, *first = NULL;
 276         struct nft_rbtree *priv = nft_set_priv(set);
 277         u8 genmask = nft_genmask_next(net);
 278         int d, err;
 279
 280         /* Descend the tree to search for an existing element greater than the
 281          * key value to insert that is greater than the new element. This is the
 282          * first element to walk the ordered elements to find possible overlap.
 283          */
 284         parent = NULL;
 285         p = &priv->root.rb_node;
 286         while (*p != NULL) {
 287                 parent = *p;
 288                 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
 289                 d = nft_rbtree_cmp(set, rbe, new);
 290
 291                 if (d < 0) {
 292                         p = &parent->rb_left;
 293                 } else if (d > 0) {
 294                         if (!first ||
 295                             nft_rbtree_update_first(set, rbe, first))
 296                                 first = &rbe->node;
 297
 298                         p = &parent->rb_right;
 299                 } else {
 300                         if (nft_rbtree_interval_end(rbe))
 301                                 p = &parent->rb_left;
 302                         else
 303                                 p = &parent->rb_right;
 304                 }
 305         }
 306
 307         if (!first)
 308                 first = rb_first(&priv->root);
 309
 310         /* Detect overlap by going through the list of valid tree nodes.
 311          * Values stored in the tree are in reversed order, starting from
 312          * highest to lowest value.
 313          */
 314         for (node = first; node != NULL; node = next) {
 315                 next = rb_next(node);
 316
 317                 rbe = rb_entry(node, struct nft_rbtree_elem, node);
 318
 319                 if (!nft_set_elem_active(&rbe->ext, genmask))
 320                         continue;
 321
 322                 /* perform garbage collection to avoid bogus overlap reports. */
 323                 if (nft_set_elem_expired(&rbe->ext)) {
 324                         err = nft_rbtree_gc_elem(set, priv, rbe);
 325                         if (err < 0)
 326                                 return err;
 327
 328                         continue;
 329                 }
 330
 331                 d = nft_rbtree_cmp(set, rbe, new);
 332                 if (d == 0) {
 333                         /* Matching end element: no need to look for an
 334                          * overlapping greater or equal element.
 335                          */
 336                         if (nft_rbtree_interval_end(rbe)) {
 337                                 rbe_le = rbe;
 338                                 break;
 339                         }
 340
 341                         /* first element that is greater or equal to key value. */
 342                         if (!rbe_ge) {
 343                                 rbe_ge = rbe;
 344                                 continue;
 345                         }
 346
 347                         /* this is a closer more or equal element, update it. */
 348                         if (nft_rbtree_cmp(set, rbe_ge, new) != 0) {
 349                                 rbe_ge = rbe;
 350                                 continue;
 351                         }
 352
 353                         /* element is equal to key value, make sure flags are
 354                          * the same, an existing more or equal start element
 355                          * must not be replaced by more or equal end element.
 356                          */
 357                         if ((nft_rbtree_interval_start(new) &&
 358                              nft_rbtree_interval_start(rbe_ge)) ||
 359                             (nft_rbtree_interval_end(new) &&
 360                              nft_rbtree_interval_end(rbe_ge))) {
 361                                 rbe_ge = rbe;
 362                                 continue;
 363                         }
 364                 } else if (d > 0) {
 365                         /* annotate element greater than the new element. */
 366                         rbe_ge = rbe;
 367                         continue;
 368                 } else if (d < 0) {
 369                         /* annotate element less than the new element. */
 370                         rbe_le = rbe;
 371                         break;
 372                 }
 373         }
 374
 375         /* - new start element matching existing start element: full overlap
 376          *   reported as -EEXIST, cleared by caller if NLM_F_EXCL is not given.
 377          */
 378         if (rbe_ge && !nft_rbtree_cmp(set, new, rbe_ge) &&
 379             nft_rbtree_interval_start(rbe_ge) == nft_rbtree_interval_start(new)) {
 380                 *ext = &rbe_ge->ext;
 381                 return -EEXIST;
 382         }
 383
 384         /* - new end element matching existing end element: full overlap
 385          *   reported as -EEXIST, cleared by caller if NLM_F_EXCL is not given.
 386          */
 387         if (rbe_le && !nft_rbtree_cmp(set, new, rbe_le) &&
 388             nft_rbtree_interval_end(rbe_le) == nft_rbtree_interval_end(new)) {
 389                 *ext = &rbe_le->ext;
 390                 return -EEXIST;
 391         }
 392
 393         /* - new start element with existing closest, less or equal key value
 394          *   being a start element: partial overlap, reported as -ENOTEMPTY.
 395          *   Anonymous sets allow for two consecutive start element since they
 396          *   are constant, skip them to avoid bogus overlap reports.
 397          */
 398         if (!nft_set_is_anonymous(set) && rbe_le &&
 399             nft_rbtree_interval_start(rbe_le) && nft_rbtree_interval_start(new))
 400                 return -ENOTEMPTY;
 401
 402         /* - new end element with existing closest, less or equal key value
 403          *   being a end element: partial overlap, reported as -ENOTEMPTY.
 404          */
 405         if (rbe_le &&
 406             nft_rbtree_interval_end(rbe_le) && nft_rbtree_interval_end(new))
 407                 return -ENOTEMPTY;
 408
 409         /* - new end element with existing closest, greater or equal key value
 410          *   being an end element: partial overlap, reported as -ENOTEMPTY
 411          */
 412         if (rbe_ge &&
 413             nft_rbtree_interval_end(rbe_ge) && nft_rbtree_interval_end(new))
 414                 return -ENOTEMPTY;
 415
 416         /* Accepted element: pick insertion point depending on key value */
 417         parent = NULL;
 418         p = &priv->root.rb_node;
 419         while (*p != NULL) {
 420                 parent = *p;
 421                 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
 422                 d = nft_rbtree_cmp(set, rbe, new);
 423
 424                 if (d < 0)
 425                         p = &parent->rb_left;
 426                 else if (d > 0)
 427                         p = &parent->rb_right;
 428                 else if (nft_rbtree_interval_end(rbe))
 429                         p = &parent->rb_left;
 430                 else
 431                         p = &parent->rb_right;
 432         }
 433
 434         rb_link_node_rcu(&new->node, parent, p);
 435         rb_insert_color(&new->node, &priv->root);
 436         return 0;
 437 }
 438
 439 static int nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 440                              const struct nft_set_elem *elem,
 441                              struct nft_set_ext **ext)
 442 {
 443         struct nft_rbtree *priv = nft_set_priv(set);
 444         struct nft_rbtree_elem *rbe = elem->priv;
 445         int err;
 446
 447         write_lock_bh(&priv->lock);
 448         write_seqcount_begin(&priv->count);
 449         err = __nft_rbtree_insert(net, set, rbe, ext);
 450         write_seqcount_end(&priv->count);
 451         write_unlock_bh(&priv->lock);
 452
 453         return err;
 454 }
 455
 456 static void nft_rbtree_remove(const struct net *net,
 457                               const struct nft_set *set,
 458                               const struct nft_set_elem *elem)
 459 {
 460         struct nft_rbtree *priv = nft_set_priv(set);
 461         struct nft_rbtree_elem *rbe = elem->priv;
 462
 463         write_lock_bh(&priv->lock);
 464         write_seqcount_begin(&priv->count);
 465         rb_erase(&rbe->node, &priv->root);
 466         write_seqcount_end(&priv->count);
 467         write_unlock_bh(&priv->lock);
 468 }
 469
 470 static void nft_rbtree_activate(const struct net *net,
 471                                 const struct nft_set *set,
 472                                 const struct nft_set_elem *elem)
 473 {
 474         struct nft_rbtree_elem *rbe = elem->priv;
 475
 476         nft_set_elem_change_active(net, set, &rbe->ext);
 477         nft_set_elem_clear_busy(&rbe->ext);
 478 }
 479
 480 static bool nft_rbtree_flush(const struct net *net,
 481                              const struct nft_set *set, void *priv)
 482 {
 483         struct nft_rbtree_elem *rbe = priv;
 484
 485         if (!nft_set_elem_mark_busy(&rbe->ext) ||
 486             !nft_is_active(net, &rbe->ext)) {
 487                 nft_set_elem_change_active(net, set, &rbe->ext);
 488                 return true;
 489         }
 490         return false;
 491 }
 492
 493 static void *nft_rbtree_deactivate(const struct net *net,
 494                                    const struct nft_set *set,
 495                                    const struct nft_set_elem *elem)
 496 {
 497         const struct nft_rbtree *priv = nft_set_priv(set);
 498         const struct rb_node *parent = priv->root.rb_node;
 499         struct nft_rbtree_elem *rbe, *this = elem->priv;
 500         u8 genmask = nft_genmask_next(net);
 501         int d;
 502
 503         while (parent != NULL) {
 504                 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
 505
 506                 d = memcmp(nft_set_ext_key(&rbe->ext), &elem->key.val,
 507                                            set->klen);
 508                 if (d < 0)
 509                         parent = parent->rb_left;
 510                 else if (d > 0)
 511                         parent = parent->rb_right;
 512                 else {
 513                         if (nft_rbtree_interval_end(rbe) &&
 514                             nft_rbtree_interval_start(this)) {
 515                                 parent = parent->rb_left;
 516                                 continue;
 517                         } else if (nft_rbtree_interval_start(rbe) &&
 518                                    nft_rbtree_interval_end(this)) {
 519                                 parent = parent->rb_right;
 520                                 continue;
 521                         } else if (!nft_set_elem_active(&rbe->ext, genmask)) {
 522                                 parent = parent->rb_left;
 523                                 continue;
 524                         }
 525                         nft_rbtree_flush(net, set, rbe);
 526                         return rbe;
 527                 }
 528         }
 529         return NULL;
 530 }
 531
 532 static void nft_rbtree_walk(const struct nft_ctx *ctx,
 533                             struct nft_set *set,
 534                             struct nft_set_iter *iter)
 535 {
 536         struct nft_rbtree *priv = nft_set_priv(set);
 537         struct nft_rbtree_elem *rbe;
 538         struct nft_set_elem elem;
 539         struct rb_node *node;
 540
 541         read_lock_bh(&priv->lock);
 542         for (node = rb_first(&priv->root); node != NULL; node = rb_next(node)) {
 543                 rbe = rb_entry(node, struct nft_rbtree_elem, node);
 544
 545                 if (iter->count < iter->skip)
 546                         goto cont;
 547                 if (nft_set_elem_expired(&rbe->ext))
 548                         goto cont;
 549                 if (!nft_set_elem_active(&rbe->ext, iter->genmask))
 550                         goto cont;
 551
 552                 elem.priv = rbe;
 553
 554                 iter->err = iter->fn(ctx, set, iter, &elem);
 555                 if (iter->err < 0) {
 556                         read_unlock_bh(&priv->lock);
 557                         return;
 558                 }
 559 cont:
 560                 iter->count++;
 561         }
 562         read_unlock_bh(&priv->lock);
 563 }
 564
 565 static void nft_rbtree_gc(struct work_struct *work)
 566 {
 567         struct nft_rbtree_elem *rbe, *rbe_end = NULL, *rbe_prev = NULL;
 568         struct nft_set_gc_batch *gcb = NULL;
 569         struct nft_rbtree *priv;
 570         struct rb_node *node;
 571         struct nft_set *set;
 572         struct net *net;
 573         u8 genmask;
 574
 575         priv = container_of(work, struct nft_rbtree, gc_work.work);
 576         set  = nft_set_container_of(priv);
 577         net  = read_pnet(&set->net);
 578         genmask = nft_genmask_cur(net);
 579
 580         write_lock_bh(&priv->lock);
 581         write_seqcount_begin(&priv->count);
 582         for (node = rb_first(&priv->root); node != NULL; node = rb_next(node)) {
 583                 rbe = rb_entry(node, struct nft_rbtree_elem, node);
 584
 585                 if (!nft_set_elem_active(&rbe->ext, genmask))
 586                         continue;
 587
 588                 /* elements are reversed in the rbtree for historical reasons,
 589                  * from highest to lowest value, that is why end element is
 590                  * always visited before the start element.
 591                  */
 592                 if (nft_rbtree_interval_end(rbe)) {
 593                         rbe_end = rbe;
 594                         continue;
 595                 }
 596                 if (!nft_set_elem_expired(&rbe->ext))
 597                         continue;
 598
 599                 if (nft_set_elem_mark_busy(&rbe->ext)) {
 600                         rbe_end = NULL;
 601                         continue;
 602                 }
 603
 604                 if (rbe_prev) {
 605                         rb_erase(&rbe_prev->node, &priv->root);
 606                         rbe_prev = NULL;
 607                 }
 608                 gcb = nft_set_gc_batch_check(set, gcb, GFP_ATOMIC);
 609                 if (!gcb)
 610                         break;
 611
 612                 atomic_dec(&set->nelems);
 613                 nft_set_gc_batch_add(gcb, rbe);
 614                 rbe_prev = rbe;
 615
 616                 if (rbe_end) {
 617                         atomic_dec(&set->nelems);
 618                         nft_set_gc_batch_add(gcb, rbe_end);
 619                         rb_erase(&rbe_end->node, &priv->root);
 620                         rbe_end = NULL;
 621                 }
 622                 node = rb_next(node);
 623                 if (!node)
 624                         break;
 625         }
 626         if (rbe_prev)
 627                 rb_erase(&rbe_prev->node, &priv->root);
 628         write_seqcount_end(&priv->count);
 629         write_unlock_bh(&priv->lock);
 630
 631         rbe = nft_set_catchall_gc(set);
 632         if (rbe) {
 633                 gcb = nft_set_gc_batch_check(set, gcb, GFP_ATOMIC);
 634                 if (gcb)
 635                         nft_set_gc_batch_add(gcb, rbe);
 636         }
 637         nft_set_gc_batch_complete(gcb);
 638
 639         queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
 640                            nft_set_gc_interval(set));
 641 }
 642
 643 static u64 nft_rbtree_privsize(const struct nlattr * const nla[],
 644                                const struct nft_set_desc *desc)
 645 {
 646         return sizeof(struct nft_rbtree);
 647 }
 648
 649 static int nft_rbtree_init(const struct nft_set *set,
 650                            const struct nft_set_desc *desc,
 651                            const struct nlattr * const nla[])
 652 {
 653         struct nft_rbtree *priv = nft_set_priv(set);
 654
 655         rwlock_init(&priv->lock);
 656         seqcount_rwlock_init(&priv->count, &priv->lock);
 657         priv->root = RB_ROOT;
 658
 659         INIT_DEFERRABLE_WORK(&priv->gc_work, nft_rbtree_gc);
 660         if (set->flags & NFT_SET_TIMEOUT)
 661                 queue_delayed_work(system_power_efficient_wq, &priv->gc_work,
 662                                    nft_set_gc_interval(set));
 663
 664         return 0;
 665 }
 666
 667 static void nft_rbtree_destroy(const struct nft_set *set)
 668 {
 669         struct nft_rbtree *priv = nft_set_priv(set);
 670         struct nft_rbtree_elem *rbe;
 671         struct rb_node *node;
 672
 673         cancel_delayed_work_sync(&priv->gc_work);
 674         rcu_barrier();
 675         while ((node = priv->root.rb_node) != NULL) {
 676                 rb_erase(node, &priv->root);
 677                 rbe = rb_entry(node, struct nft_rbtree_elem, node);
 678                 nft_set_elem_destroy(set, rbe, true);
 679         }
 680 }
 681
 682 static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
 683                                 struct nft_set_estimate *est)
 684 {
 685         if (desc->field_count > 1)
 686                 return false;
 687
 688         if (desc->size)
 689                 est->size = sizeof(struct nft_rbtree) +
 690                             desc->size * sizeof(struct nft_rbtree_elem);
 691         else
 692                 est->size = ~0;
 693
 694         est->lookup = NFT_SET_CLASS_O_LOG_N;
 695         est->space  = NFT_SET_CLASS_O_N;
 696
 697         return true;
 698 }
 699
 700 const struct nft_set_type nft_set_rbtree_type = {
 701         .features       = NFT_SET_INTERVAL | NFT_SET_MAP | NFT_SET_OBJECT | NFT_SET_TIMEOUT,
 702         .ops            = {
 703                 .privsize       = nft_rbtree_privsize,
 704                 .elemsize       = offsetof(struct nft_rbtree_elem, ext),
 705                 .estimate       = nft_rbtree_estimate,
 706                 .init           = nft_rbtree_init,
 707                 .destroy        = nft_rbtree_destroy,
 708                 .insert         = nft_rbtree_insert,
 709                 .remove         = nft_rbtree_remove,
 710                 .deactivate     = nft_rbtree_deactivate,
 711                 .flush          = nft_rbtree_flush,
 712                 .activate       = nft_rbtree_activate,
 713                 .lookup         = nft_rbtree_lookup,
 714                 .walk           = nft_rbtree_walk,
 715                 .get            = nft_rbtree_get,
 716         },
 717 };