net/sched/cls_tcindex.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
tcindex_filter_is_set
tcindex_data_get
tcindex_data_put
tcindex_lookup
tcindex_classify
tcindex_get
tcindex_init
__tcindex_destroy_rexts
tcindex_destroy_rexts_work
__tcindex_destroy_fexts
tcindex_destroy_fexts_work
tcindex_delete
tcindex_destroy_work
valid_perfect_hash
tcindex_filter_result_init
tcindex_partial_destroy_work
tcindex_free_perfect_hash
tcindex_alloc_perfect_hash
tcindex_set_parms
tcindex_change
tcindex_walk
tcindex_destroy
tcindex_dump
tcindex_bind_class
init_tcindex
exit_tcindex
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * net/sched/cls_tcindex.c      Packet classifier for skb->tc_index
   4  *
   5  * Written 1998,1999 by Werner Almesberger, EPFL ICA
   6  */
   7 
   8 #include <linux/module.h>
   9 #include <linux/types.h>
  10 #include <linux/kernel.h>
  11 #include <linux/skbuff.h>
  12 #include <linux/errno.h>
  13 #include <linux/slab.h>
  14 #include <linux/refcount.h>
  15 #include <net/act_api.h>
  16 #include <net/netlink.h>
  17 #include <net/pkt_cls.h>
  18 #include <net/sch_generic.h>
  19 
  20 /*
  21  * Passing parameters to the root seems to be done more awkwardly than really
  22  * necessary. At least, u32 doesn't seem to use such dirty hacks. To be
  23  * verified. FIXME.
  24  */
  25 
  26 #define PERFECT_HASH_THRESHOLD  64      /* use perfect hash if not bigger */
  27 #define DEFAULT_HASH_SIZE       64      /* optimized for diffserv */
  28 
  29 
  30 struct tcindex_data;
  31 
  32 struct tcindex_filter_result {
  33         struct tcf_exts         exts;
  34         struct tcf_result       res;
  35         struct tcindex_data     *p;
  36         struct rcu_work         rwork;
  37 };
  38 
  39 struct tcindex_filter {
  40         u16 key;
  41         struct tcindex_filter_result result;
  42         struct tcindex_filter __rcu *next;
  43         struct rcu_work rwork;
  44 };
  45 
  46 
  47 struct tcindex_data {
  48         struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
  49         struct tcindex_filter __rcu **h; /* imperfect hash; */
  50         struct tcf_proto *tp;
  51         u16 mask;               /* AND key with mask */
  52         u32 shift;              /* shift ANDed key to the right */
  53         u32 hash;               /* hash table size; 0 if undefined */
  54         u32 alloc_hash;         /* allocated size */
  55         u32 fall_through;       /* 0: only classify if explicit match */
  56         refcount_t refcnt;      /* a temporary refcnt for perfect hash */
  57         struct rcu_work rwork;
  58 };
  59 
  60 static inline int tcindex_filter_is_set(struct tcindex_filter_result *r)
  61 {
  62         return tcf_exts_has_actions(&r->exts) || r->res.classid;
  63 }
  64 
  65 static void tcindex_data_get(struct tcindex_data *p)
  66 {
  67         refcount_inc(&p->refcnt);
  68 }
  69 
  70 static void tcindex_data_put(struct tcindex_data *p)
  71 {
  72         if (refcount_dec_and_test(&p->refcnt)) {
  73                 kfree(p->perfect);
  74                 kfree(p->h);
  75                 kfree(p);
  76         }
  77 }
  78 
  79 static struct tcindex_filter_result *tcindex_lookup(struct tcindex_data *p,
  80                                                     u16 key)
  81 {
  82         if (p->perfect) {
  83                 struct tcindex_filter_result *f = p->perfect + key;
  84 
  85                 return tcindex_filter_is_set(f) ? f : NULL;
  86         } else if (p->h) {
  87                 struct tcindex_filter __rcu **fp;
  88                 struct tcindex_filter *f;
  89 
  90                 fp = &p->h[key % p->hash];
  91                 for (f = rcu_dereference_bh_rtnl(*fp);
  92                      f;
  93                      fp = &f->next, f = rcu_dereference_bh_rtnl(*fp))
  94                         if (f->key == key)
  95                                 return &f->result;
  96         }
  97 
  98         return NULL;
  99 }
 100 
 101 
 102 static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 103                             struct tcf_result *res)
 104 {
 105         struct tcindex_data *p = rcu_dereference_bh(tp->root);
 106         struct tcindex_filter_result *f;
 107         int key = (skb->tc_index & p->mask) >> p->shift;
 108 
 109         pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
 110                  skb, tp, res, p);
 111 
 112         f = tcindex_lookup(p, key);
 113         if (!f) {
 114                 struct Qdisc *q = tcf_block_q(tp->chain->block);
 115 
 116                 if (!p->fall_through)
 117                         return -1;
 118                 res->classid = TC_H_MAKE(TC_H_MAJ(q->handle), key);
 119                 res->class = 0;
 120                 pr_debug("alg 0x%x\n", res->classid);
 121                 return 0;
 122         }
 123         *res = f->res;
 124         pr_debug("map 0x%x\n", res->classid);
 125 
 126         return tcf_exts_exec(skb, &f->exts, res);
 127 }
 128 
 129 
 130 static void *tcindex_get(struct tcf_proto *tp, u32 handle)
 131 {
 132         struct tcindex_data *p = rtnl_dereference(tp->root);
 133         struct tcindex_filter_result *r;
 134 
 135         pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
 136         if (p->perfect && handle >= p->alloc_hash)
 137                 return NULL;
 138         r = tcindex_lookup(p, handle);
 139         return r && tcindex_filter_is_set(r) ? r : NULL;
 140 }
 141 
 142 static int tcindex_init(struct tcf_proto *tp)
 143 {
 144         struct tcindex_data *p;
 145 
 146         pr_debug("tcindex_init(tp %p)\n", tp);
 147         p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
 148         if (!p)
 149                 return -ENOMEM;
 150 
 151         p->mask = 0xffff;
 152         p->hash = DEFAULT_HASH_SIZE;
 153         p->fall_through = 1;
 154         refcount_set(&p->refcnt, 1); /* Paired with tcindex_destroy_work() */
 155 
 156         rcu_assign_pointer(tp->root, p);
 157         return 0;
 158 }
 159 
 160 static void __tcindex_destroy_rexts(struct tcindex_filter_result *r)
 161 {
 162         tcf_exts_destroy(&r->exts);
 163         tcf_exts_put_net(&r->exts);
 164         tcindex_data_put(r->p);
 165 }
 166 
 167 static void tcindex_destroy_rexts_work(struct work_struct *work)
 168 {
 169         struct tcindex_filter_result *r;
 170 
 171         r = container_of(to_rcu_work(work),
 172                          struct tcindex_filter_result,
 173                          rwork);
 174         rtnl_lock();
 175         __tcindex_destroy_rexts(r);
 176         rtnl_unlock();
 177 }
 178 
 179 static void __tcindex_destroy_fexts(struct tcindex_filter *f)
 180 {
 181         tcf_exts_destroy(&f->result.exts);
 182         tcf_exts_put_net(&f->result.exts);
 183         kfree(f);
 184 }
 185 
 186 static void tcindex_destroy_fexts_work(struct work_struct *work)
 187 {
 188         struct tcindex_filter *f = container_of(to_rcu_work(work),
 189                                                 struct tcindex_filter,
 190                                                 rwork);
 191 
 192         rtnl_lock();
 193         __tcindex_destroy_fexts(f);
 194         rtnl_unlock();
 195 }
 196 
 197 static int tcindex_delete(struct tcf_proto *tp, void *arg, bool *last,
 198                           bool rtnl_held, struct netlink_ext_ack *extack)
 199 {
 200         struct tcindex_data *p = rtnl_dereference(tp->root);
 201         struct tcindex_filter_result *r = arg;
 202         struct tcindex_filter __rcu **walk;
 203         struct tcindex_filter *f = NULL;
 204 
 205         pr_debug("tcindex_delete(tp %p,arg %p),p %p\n", tp, arg, p);
 206         if (p->perfect) {
 207                 if (!r->res.class)
 208                         return -ENOENT;
 209         } else {
 210                 int i;
 211 
 212                 for (i = 0; i < p->hash; i++) {
 213                         walk = p->h + i;
 214                         for (f = rtnl_dereference(*walk); f;
 215                              walk = &f->next, f = rtnl_dereference(*walk)) {
 216                                 if (&f->result == r)
 217                                         goto found;
 218                         }
 219                 }
 220                 return -ENOENT;
 221 
 222 found:
 223                 rcu_assign_pointer(*walk, rtnl_dereference(f->next));
 224         }
 225         tcf_unbind_filter(tp, &r->res);
 226         /* all classifiers are required to call tcf_exts_destroy() after rcu
 227          * grace period, since converted-to-rcu actions are relying on that
 228          * in cleanup() callback
 229          */
 230         if (f) {
 231                 if (tcf_exts_get_net(&f->result.exts))
 232                         tcf_queue_work(&f->rwork, tcindex_destroy_fexts_work);
 233                 else
 234                         __tcindex_destroy_fexts(f);
 235         } else {
 236                 tcindex_data_get(p);
 237 
 238                 if (tcf_exts_get_net(&r->exts))
 239                         tcf_queue_work(&r->rwork, tcindex_destroy_rexts_work);
 240                 else
 241                         __tcindex_destroy_rexts(r);
 242         }
 243 
 244         *last = false;
 245         return 0;
 246 }
 247 
 248 static void tcindex_destroy_work(struct work_struct *work)
 249 {
 250         struct tcindex_data *p = container_of(to_rcu_work(work),
 251                                               struct tcindex_data,
 252                                               rwork);
 253 
 254         tcindex_data_put(p);
 255 }
 256 
 257 static inline int
 258 valid_perfect_hash(struct tcindex_data *p)
 259 {
 260         return  p->hash > (p->mask >> p->shift);
 261 }
 262 
 263 static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
 264         [TCA_TCINDEX_HASH]              = { .type = NLA_U32 },
 265         [TCA_TCINDEX_MASK]              = { .type = NLA_U16 },
 266         [TCA_TCINDEX_SHIFT]             = { .type = NLA_U32 },
 267         [TCA_TCINDEX_FALL_THROUGH]      = { .type = NLA_U32 },
 268         [TCA_TCINDEX_CLASSID]           = { .type = NLA_U32 },
 269 };
 270 
 271 static int tcindex_filter_result_init(struct tcindex_filter_result *r,
 272                                       struct tcindex_data *p,
 273                                       struct net *net)
 274 {
 275         memset(r, 0, sizeof(*r));
 276         r->p = p;
 277         return tcf_exts_init(&r->exts, net, TCA_TCINDEX_ACT,
 278                              TCA_TCINDEX_POLICE);
 279 }
 280 
 281 static void tcindex_partial_destroy_work(struct work_struct *work)
 282 {
 283         struct tcindex_data *p = container_of(to_rcu_work(work),
 284                                               struct tcindex_data,
 285                                               rwork);
 286 
 287         rtnl_lock();
 288         kfree(p->perfect);
 289         kfree(p);
 290         rtnl_unlock();
 291 }
 292 
 293 static void tcindex_free_perfect_hash(struct tcindex_data *cp)
 294 {
 295         int i;
 296 
 297         for (i = 0; i < cp->hash; i++)
 298                 tcf_exts_destroy(&cp->perfect[i].exts);
 299         kfree(cp->perfect);
 300 }
 301 
 302 static int tcindex_alloc_perfect_hash(struct net *net, struct tcindex_data *cp)
 303 {
 304         int i, err = 0;
 305 
 306         cp->perfect = kcalloc(cp->hash, sizeof(struct tcindex_filter_result),
 307                               GFP_KERNEL);
 308         if (!cp->perfect)
 309                 return -ENOMEM;
 310 
 311         for (i = 0; i < cp->hash; i++) {
 312                 err = tcf_exts_init(&cp->perfect[i].exts, net,
 313                                     TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 314                 if (err < 0)
 315                         goto errout;
 316                 cp->perfect[i].p = cp;
 317         }
 318 
 319         return 0;
 320 
 321 errout:
 322         tcindex_free_perfect_hash(cp);
 323         return err;
 324 }
 325 
 326 static int
 327 tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 328                   u32 handle, struct tcindex_data *p,
 329                   struct tcindex_filter_result *r, struct nlattr **tb,
 330                   struct nlattr *est, bool ovr, struct netlink_ext_ack *extack)
 331 {
 332         struct tcindex_filter_result new_filter_result, *old_r = r;
 333         struct tcindex_data *cp = NULL, *oldp;
 334         struct tcindex_filter *f = NULL; /* make gcc behave */
 335         struct tcf_result cr = {};
 336         int err, balloc = 0;
 337         struct tcf_exts e;
 338 
 339         err = tcf_exts_init(&e, net, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 340         if (err < 0)
 341                 return err;
 342         err = tcf_exts_validate(net, tp, tb, est, &e, ovr, true, extack);
 343         if (err < 0)
 344                 goto errout;
 345 
 346         err = -ENOMEM;
 347         /* tcindex_data attributes must look atomic to classifier/lookup so
 348          * allocate new tcindex data and RCU assign it onto root. Keeping
 349          * perfect hash and hash pointers from old data.
 350          */
 351         cp = kzalloc(sizeof(*cp), GFP_KERNEL);
 352         if (!cp)
 353                 goto errout;
 354 
 355         cp->mask = p->mask;
 356         cp->shift = p->shift;
 357         cp->hash = p->hash;
 358         cp->alloc_hash = p->alloc_hash;
 359         cp->fall_through = p->fall_through;
 360         cp->tp = tp;
 361         refcount_set(&cp->refcnt, 1); /* Paired with tcindex_destroy_work() */
 362 
 363         if (tb[TCA_TCINDEX_HASH])
 364                 cp->hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
 365 
 366         if (tb[TCA_TCINDEX_MASK])
 367                 cp->mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
 368 
 369         if (tb[TCA_TCINDEX_SHIFT])
 370                 cp->shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
 371 
 372         if (!cp->hash) {
 373                 /* Hash not specified, use perfect hash if the upper limit
 374                  * of the hashing index is below the threshold.
 375                  */
 376                 if ((cp->mask >> cp->shift) < PERFECT_HASH_THRESHOLD)
 377                         cp->hash = (cp->mask >> cp->shift) + 1;
 378                 else
 379                         cp->hash = DEFAULT_HASH_SIZE;
 380         }
 381 
 382         if (p->perfect) {
 383                 int i;
 384 
 385                 if (tcindex_alloc_perfect_hash(net, cp) < 0)
 386                         goto errout;
 387                 cp->alloc_hash = cp->hash;
 388                 for (i = 0; i < min(cp->hash, p->hash); i++)
 389                         cp->perfect[i].res = p->perfect[i].res;
 390                 balloc = 1;
 391         }
 392         cp->h = p->h;
 393 
 394         err = tcindex_filter_result_init(&new_filter_result, cp, net);
 395         if (err < 0)
 396                 goto errout_alloc;
 397         if (old_r)
 398                 cr = r->res;
 399 
 400         err = -EBUSY;
 401 
 402         /* Hash already allocated, make sure that we still meet the
 403          * requirements for the allocated hash.
 404          */
 405         if (cp->perfect) {
 406                 if (!valid_perfect_hash(cp) ||
 407                     cp->hash > cp->alloc_hash)
 408                         goto errout_alloc;
 409         } else if (cp->h && cp->hash != cp->alloc_hash) {
 410                 goto errout_alloc;
 411         }
 412 
 413         err = -EINVAL;
 414         if (tb[TCA_TCINDEX_FALL_THROUGH])
 415                 cp->fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
 416 
 417         if (!cp->perfect && !cp->h)
 418                 cp->alloc_hash = cp->hash;
 419 
 420         /* Note: this could be as restrictive as if (handle & ~(mask >> shift))
 421          * but then, we'd fail handles that may become valid after some future
 422          * mask change. While this is extremely unlikely to ever matter,
 423          * the check below is safer (and also more backwards-compatible).
 424          */
 425         if (cp->perfect || valid_perfect_hash(cp))
 426                 if (handle >= cp->alloc_hash)
 427                         goto errout_alloc;
 428 
 429 
 430         err = -ENOMEM;
 431         if (!cp->perfect && !cp->h) {
 432                 if (valid_perfect_hash(cp)) {
 433                         if (tcindex_alloc_perfect_hash(net, cp) < 0)
 434                                 goto errout_alloc;
 435                         balloc = 1;
 436                 } else {
 437                         struct tcindex_filter __rcu **hash;
 438 
 439                         hash = kcalloc(cp->hash,
 440                                        sizeof(struct tcindex_filter *),
 441                                        GFP_KERNEL);
 442 
 443                         if (!hash)
 444                                 goto errout_alloc;
 445 
 446                         cp->h = hash;
 447                         balloc = 2;
 448                 }
 449         }
 450 
 451         if (cp->perfect)
 452                 r = cp->perfect + handle;
 453         else
 454                 r = tcindex_lookup(cp, handle) ? : &new_filter_result;
 455 
 456         if (r == &new_filter_result) {
 457                 f = kzalloc(sizeof(*f), GFP_KERNEL);
 458                 if (!f)
 459                         goto errout_alloc;
 460                 f->key = handle;
 461                 f->next = NULL;
 462                 err = tcindex_filter_result_init(&f->result, cp, net);
 463                 if (err < 0) {
 464                         kfree(f);
 465                         goto errout_alloc;
 466                 }
 467         }
 468 
 469         if (tb[TCA_TCINDEX_CLASSID]) {
 470                 cr.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
 471                 tcf_bind_filter(tp, &cr, base);
 472         }
 473 
 474         if (old_r && old_r != r) {
 475                 err = tcindex_filter_result_init(old_r, cp, net);
 476                 if (err < 0) {
 477                         kfree(f);
 478                         goto errout_alloc;
 479                 }
 480         }
 481 
 482         oldp = p;
 483         r->res = cr;
 484         tcf_exts_change(&r->exts, &e);
 485 
 486         rcu_assign_pointer(tp->root, cp);
 487 
 488         if (r == &new_filter_result) {
 489                 struct tcindex_filter *nfp;
 490                 struct tcindex_filter __rcu **fp;
 491 
 492                 f->result.res = r->res;
 493                 tcf_exts_change(&f->result.exts, &r->exts);
 494 
 495                 fp = cp->h + (handle % cp->hash);
 496                 for (nfp = rtnl_dereference(*fp);
 497                      nfp;
 498                      fp = &nfp->next, nfp = rtnl_dereference(*fp))
 499                                 ; /* nothing */
 500 
 501                 rcu_assign_pointer(*fp, f);
 502         } else {
 503                 tcf_exts_destroy(&new_filter_result.exts);
 504         }
 505 
 506         if (oldp)
 507                 tcf_queue_work(&oldp->rwork, tcindex_partial_destroy_work);
 508         return 0;
 509 
 510 errout_alloc:
 511         if (balloc == 1)
 512                 tcindex_free_perfect_hash(cp);
 513         else if (balloc == 2)
 514                 kfree(cp->h);
 515         tcf_exts_destroy(&new_filter_result.exts);
 516 errout:
 517         kfree(cp);
 518         tcf_exts_destroy(&e);
 519         return err;
 520 }
 521 
 522 static int
 523 tcindex_change(struct net *net, struct sk_buff *in_skb,
 524                struct tcf_proto *tp, unsigned long base, u32 handle,
 525                struct nlattr **tca, void **arg, bool ovr,
 526                bool rtnl_held, struct netlink_ext_ack *extack)
 527 {
 528         struct nlattr *opt = tca[TCA_OPTIONS];
 529         struct nlattr *tb[TCA_TCINDEX_MAX + 1];
 530         struct tcindex_data *p = rtnl_dereference(tp->root);
 531         struct tcindex_filter_result *r = *arg;
 532         int err;
 533 
 534         pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
 535             "p %p,r %p,*arg %p\n",
 536             tp, handle, tca, arg, opt, p, r, arg ? *arg : NULL);
 537 
 538         if (!opt)
 539                 return 0;
 540 
 541         err = nla_parse_nested_deprecated(tb, TCA_TCINDEX_MAX, opt,
 542                                           tcindex_policy, NULL);
 543         if (err < 0)
 544                 return err;
 545 
 546         return tcindex_set_parms(net, tp, base, handle, p, r, tb,
 547                                  tca[TCA_RATE], ovr, extack);
 548 }
 549 
 550 static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker,
 551                          bool rtnl_held)
 552 {
 553         struct tcindex_data *p = rtnl_dereference(tp->root);
 554         struct tcindex_filter *f, *next;
 555         int i;
 556 
 557         pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
 558         if (p->perfect) {
 559                 for (i = 0; i < p->hash; i++) {
 560                         if (!p->perfect[i].res.class)
 561                                 continue;
 562                         if (walker->count >= walker->skip) {
 563                                 if (walker->fn(tp, p->perfect + i, walker) < 0) {
 564                                         walker->stop = 1;
 565                                         return;
 566                                 }
 567                         }
 568                         walker->count++;
 569                 }
 570         }
 571         if (!p->h)
 572                 return;
 573         for (i = 0; i < p->hash; i++) {
 574                 for (f = rtnl_dereference(p->h[i]); f; f = next) {
 575                         next = rtnl_dereference(f->next);
 576                         if (walker->count >= walker->skip) {
 577                                 if (walker->fn(tp, &f->result, walker) < 0) {
 578                                         walker->stop = 1;
 579                                         return;
 580                                 }
 581                         }
 582                         walker->count++;
 583                 }
 584         }
 585 }
 586 
 587 static void tcindex_destroy(struct tcf_proto *tp, bool rtnl_held,
 588                             struct netlink_ext_ack *extack)
 589 {
 590         struct tcindex_data *p = rtnl_dereference(tp->root);
 591         int i;
 592 
 593         pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
 594 
 595         if (p->perfect) {
 596                 for (i = 0; i < p->hash; i++) {
 597                         struct tcindex_filter_result *r = p->perfect + i;
 598 
 599                         /* tcf_queue_work() does not guarantee the ordering we
 600                          * want, so we have to take this refcnt temporarily to
 601                          * ensure 'p' is freed after all tcindex_filter_result
 602                          * here. Imperfect hash does not need this, because it
 603                          * uses linked lists rather than an array.
 604                          */
 605                         tcindex_data_get(p);
 606 
 607                         tcf_unbind_filter(tp, &r->res);
 608                         if (tcf_exts_get_net(&r->exts))
 609                                 tcf_queue_work(&r->rwork,
 610                                                tcindex_destroy_rexts_work);
 611                         else
 612                                 __tcindex_destroy_rexts(r);
 613                 }
 614         }
 615 
 616         for (i = 0; p->h && i < p->hash; i++) {
 617                 struct tcindex_filter *f, *next;
 618                 bool last;
 619 
 620                 for (f = rtnl_dereference(p->h[i]); f; f = next) {
 621                         next = rtnl_dereference(f->next);
 622                         tcindex_delete(tp, &f->result, &last, rtnl_held, NULL);
 623                 }
 624         }
 625 
 626         tcf_queue_work(&p->rwork, tcindex_destroy_work);
 627 }
 628 
 629 
 630 static int tcindex_dump(struct net *net, struct tcf_proto *tp, void *fh,
 631                         struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
 632 {
 633         struct tcindex_data *p = rtnl_dereference(tp->root);
 634         struct tcindex_filter_result *r = fh;
 635         struct nlattr *nest;
 636 
 637         pr_debug("tcindex_dump(tp %p,fh %p,skb %p,t %p),p %p,r %p\n",
 638                  tp, fh, skb, t, p, r);
 639         pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);
 640 
 641         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 642         if (nest == NULL)
 643                 goto nla_put_failure;
 644 
 645         if (!fh) {
 646                 t->tcm_handle = ~0; /* whatever ... */
 647                 if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) ||
 648                     nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) ||
 649                     nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) ||
 650                     nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through))
 651                         goto nla_put_failure;
 652                 nla_nest_end(skb, nest);
 653         } else {
 654                 if (p->perfect) {
 655                         t->tcm_handle = r - p->perfect;
 656                 } else {
 657                         struct tcindex_filter *f;
 658                         struct tcindex_filter __rcu **fp;
 659                         int i;
 660 
 661                         t->tcm_handle = 0;
 662                         for (i = 0; !t->tcm_handle && i < p->hash; i++) {
 663                                 fp = &p->h[i];
 664                                 for (f = rtnl_dereference(*fp);
 665                                      !t->tcm_handle && f;
 666                                      fp = &f->next, f = rtnl_dereference(*fp)) {
 667                                         if (&f->result == r)
 668                                                 t->tcm_handle = f->key;
 669                                 }
 670                         }
 671                 }
 672                 pr_debug("handle = %d\n", t->tcm_handle);
 673                 if (r->res.class &&
 674                     nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid))
 675                         goto nla_put_failure;
 676 
 677                 if (tcf_exts_dump(skb, &r->exts) < 0)
 678                         goto nla_put_failure;
 679                 nla_nest_end(skb, nest);
 680 
 681                 if (tcf_exts_dump_stats(skb, &r->exts) < 0)
 682                         goto nla_put_failure;
 683         }
 684 
 685         return skb->len;
 686 
 687 nla_put_failure:
 688         nla_nest_cancel(skb, nest);
 689         return -1;
 690 }
 691 
 692 static void tcindex_bind_class(void *fh, u32 classid, unsigned long cl,
 693                                void *q, unsigned long base)
 694 {
 695         struct tcindex_filter_result *r = fh;
 696 
 697         if (r && r->res.classid == classid) {
 698                 if (cl)
 699                         __tcf_bind_filter(q, &r->res, base);
 700                 else
 701                         __tcf_unbind_filter(q, &r->res);
 702         }
 703 }
 704 
 705 static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
 706         .kind           =       "tcindex",
 707         .classify       =       tcindex_classify,
 708         .init           =       tcindex_init,
 709         .destroy        =       tcindex_destroy,
 710         .get            =       tcindex_get,
 711         .change         =       tcindex_change,
 712         .delete         =       tcindex_delete,
 713         .walk           =       tcindex_walk,
 714         .dump           =       tcindex_dump,
 715         .bind_class     =       tcindex_bind_class,
 716         .owner          =       THIS_MODULE,
 717 };
 718 
 719 static int __init init_tcindex(void)
 720 {
 721         return register_tcf_proto_ops(&cls_tcindex_ops);
 722 }
 723 
 724 static void __exit exit_tcindex(void)
 725 {
 726         unregister_tcf_proto_ops(&cls_tcindex_ops);
 727 }
 728 
 729 module_init(init_tcindex)
 730 module_exit(exit_tcindex)
 731 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/net/sched/cls_tcindex.c

DEFINITIONS
