xref: /openbmc/linux/net/sched/cls_u32.c (revision c4d49196)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/sched/cls_u32.c	Ugly (or Universal) 32bit key Packet Classifier.
4  *
5  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6  *
7  *	The filters are packed to hash tables of key nodes
8  *	with a set of 32bit key/mask pairs at every node.
9  *	Nodes reference next level hash tables etc.
10  *
11  *	This scheme is the best universal classifier I managed to
12  *	invent; it is not super-fast, but it is not slow (provided you
13  *	program it correctly), and general enough.  And its relative
14  *	speed grows as the number of rules becomes larger.
15  *
16  *	It seems that it represents the best middle point between
17  *	speed and manageability both by human and by machine.
18  *
19  *	It is especially useful for link sharing combined with QoS;
20  *	pure RSVP doesn't need such a general approach and can use
21  *	much simpler (and faster) schemes, sort of cls_rsvp.c.
22  *
23  *	nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
24  */
25 
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/types.h>
29 #include <linux/kernel.h>
30 #include <linux/string.h>
31 #include <linux/errno.h>
32 #include <linux/percpu.h>
33 #include <linux/rtnetlink.h>
34 #include <linux/skbuff.h>
35 #include <linux/bitmap.h>
36 #include <linux/netdevice.h>
37 #include <linux/hash.h>
38 #include <net/netlink.h>
39 #include <net/act_api.h>
40 #include <net/pkt_cls.h>
41 #include <linux/idr.h>
42 #include <net/tc_wrapper.h>
43 
44 struct tc_u_knode {
45 	struct tc_u_knode __rcu	*next;
46 	u32			handle;
47 	struct tc_u_hnode __rcu	*ht_up;
48 	struct tcf_exts		exts;
49 	int			ifindex;
50 	u8			fshift;
51 	struct tcf_result	res;
52 	struct tc_u_hnode __rcu	*ht_down;
53 #ifdef CONFIG_CLS_U32_PERF
54 	struct tc_u32_pcnt __percpu *pf;
55 #endif
56 	u32			flags;
57 	unsigned int		in_hw_count;
58 #ifdef CONFIG_CLS_U32_MARK
59 	u32			val;
60 	u32			mask;
61 	u32 __percpu		*pcpu_success;
62 #endif
63 	struct rcu_work		rwork;
64 	/* The 'sel' field MUST be the last field in structure to allow for
65 	 * tc_u32_keys allocated at end of structure.
66 	 */
67 	struct tc_u32_sel	sel;
68 };
69 
70 struct tc_u_hnode {
71 	struct tc_u_hnode __rcu	*next;
72 	u32			handle;
73 	u32			prio;
74 	int			refcnt;
75 	unsigned int		divisor;
76 	struct idr		handle_idr;
77 	bool			is_root;
78 	struct rcu_head		rcu;
79 	u32			flags;
80 	/* The 'ht' field MUST be the last field in structure to allow for
81 	 * more entries allocated at end of structure.
82 	 */
83 	struct tc_u_knode __rcu	*ht[];
84 };
85 
86 struct tc_u_common {
87 	struct tc_u_hnode __rcu	*hlist;
88 	void			*ptr;
89 	int			refcnt;
90 	struct idr		handle_idr;
91 	struct hlist_node	hnode;
92 	long			knodes;
93 };
94 
u32_hash_fold(__be32 key,const struct tc_u32_sel * sel,u8 fshift)95 static inline unsigned int u32_hash_fold(__be32 key,
96 					 const struct tc_u32_sel *sel,
97 					 u8 fshift)
98 {
99 	unsigned int h = ntohl(key & sel->hmask) >> fshift;
100 
101 	return h;
102 }
103 
u32_classify(struct sk_buff * skb,const struct tcf_proto * tp,struct tcf_result * res)104 TC_INDIRECT_SCOPE int u32_classify(struct sk_buff *skb,
105 				   const struct tcf_proto *tp,
106 				   struct tcf_result *res)
107 {
108 	struct {
109 		struct tc_u_knode *knode;
110 		unsigned int	  off;
111 	} stack[TC_U32_MAXDEPTH];
112 
113 	struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
114 	unsigned int off = skb_network_offset(skb);
115 	struct tc_u_knode *n;
116 	int sdepth = 0;
117 	int off2 = 0;
118 	int sel = 0;
119 #ifdef CONFIG_CLS_U32_PERF
120 	int j;
121 #endif
122 	int i, r;
123 
124 next_ht:
125 	n = rcu_dereference_bh(ht->ht[sel]);
126 
127 next_knode:
128 	if (n) {
129 		struct tc_u32_key *key = n->sel.keys;
130 
131 #ifdef CONFIG_CLS_U32_PERF
132 		__this_cpu_inc(n->pf->rcnt);
133 		j = 0;
134 #endif
135 
136 		if (tc_skip_sw(n->flags)) {
137 			n = rcu_dereference_bh(n->next);
138 			goto next_knode;
139 		}
140 
141 #ifdef CONFIG_CLS_U32_MARK
142 		if ((skb->mark & n->mask) != n->val) {
143 			n = rcu_dereference_bh(n->next);
144 			goto next_knode;
145 		} else {
146 			__this_cpu_inc(*n->pcpu_success);
147 		}
148 #endif
149 
150 		for (i = n->sel.nkeys; i > 0; i--, key++) {
151 			int toff = off + key->off + (off2 & key->offmask);
152 			__be32 *data, hdata;
153 
154 			if (skb_headroom(skb) + toff > INT_MAX)
155 				goto out;
156 
157 			data = skb_header_pointer(skb, toff, 4, &hdata);
158 			if (!data)
159 				goto out;
160 			if ((*data ^ key->val) & key->mask) {
161 				n = rcu_dereference_bh(n->next);
162 				goto next_knode;
163 			}
164 #ifdef CONFIG_CLS_U32_PERF
165 			__this_cpu_inc(n->pf->kcnts[j]);
166 			j++;
167 #endif
168 		}
169 
170 		ht = rcu_dereference_bh(n->ht_down);
171 		if (!ht) {
172 check_terminal:
173 			if (n->sel.flags & TC_U32_TERMINAL) {
174 
175 				*res = n->res;
176 				if (!tcf_match_indev(skb, n->ifindex)) {
177 					n = rcu_dereference_bh(n->next);
178 					goto next_knode;
179 				}
180 #ifdef CONFIG_CLS_U32_PERF
181 				__this_cpu_inc(n->pf->rhit);
182 #endif
183 				r = tcf_exts_exec(skb, &n->exts, res);
184 				if (r < 0) {
185 					n = rcu_dereference_bh(n->next);
186 					goto next_knode;
187 				}
188 
189 				return r;
190 			}
191 			n = rcu_dereference_bh(n->next);
192 			goto next_knode;
193 		}
194 
195 		/* PUSH */
196 		if (sdepth >= TC_U32_MAXDEPTH)
197 			goto deadloop;
198 		stack[sdepth].knode = n;
199 		stack[sdepth].off = off;
200 		sdepth++;
201 
202 		ht = rcu_dereference_bh(n->ht_down);
203 		sel = 0;
204 		if (ht->divisor) {
205 			__be32 *data, hdata;
206 
207 			data = skb_header_pointer(skb, off + n->sel.hoff, 4,
208 						  &hdata);
209 			if (!data)
210 				goto out;
211 			sel = ht->divisor & u32_hash_fold(*data, &n->sel,
212 							  n->fshift);
213 		}
214 		if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
215 			goto next_ht;
216 
217 		if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
218 			off2 = n->sel.off + 3;
219 			if (n->sel.flags & TC_U32_VAROFFSET) {
220 				__be16 *data, hdata;
221 
222 				data = skb_header_pointer(skb,
223 							  off + n->sel.offoff,
224 							  2, &hdata);
225 				if (!data)
226 					goto out;
227 				off2 += ntohs(n->sel.offmask & *data) >>
228 					n->sel.offshift;
229 			}
230 			off2 &= ~3;
231 		}
232 		if (n->sel.flags & TC_U32_EAT) {
233 			off += off2;
234 			off2 = 0;
235 		}
236 
237 		if (off < skb->len)
238 			goto next_ht;
239 	}
240 
241 	/* POP */
242 	if (sdepth--) {
243 		n = stack[sdepth].knode;
244 		ht = rcu_dereference_bh(n->ht_up);
245 		off = stack[sdepth].off;
246 		goto check_terminal;
247 	}
248 out:
249 	return -1;
250 
251 deadloop:
252 	net_warn_ratelimited("cls_u32: dead loop\n");
253 	return -1;
254 }
255 
u32_lookup_ht(struct tc_u_common * tp_c,u32 handle)256 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
257 {
258 	struct tc_u_hnode *ht;
259 
260 	for (ht = rtnl_dereference(tp_c->hlist);
261 	     ht;
262 	     ht = rtnl_dereference(ht->next))
263 		if (ht->handle == handle)
264 			break;
265 
266 	return ht;
267 }
268 
u32_lookup_key(struct tc_u_hnode * ht,u32 handle)269 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
270 {
271 	unsigned int sel;
272 	struct tc_u_knode *n = NULL;
273 
274 	sel = TC_U32_HASH(handle);
275 	if (sel > ht->divisor)
276 		goto out;
277 
278 	for (n = rtnl_dereference(ht->ht[sel]);
279 	     n;
280 	     n = rtnl_dereference(n->next))
281 		if (n->handle == handle)
282 			break;
283 out:
284 	return n;
285 }
286 
287 
u32_get(struct tcf_proto * tp,u32 handle)288 static void *u32_get(struct tcf_proto *tp, u32 handle)
289 {
290 	struct tc_u_hnode *ht;
291 	struct tc_u_common *tp_c = tp->data;
292 
293 	if (TC_U32_HTID(handle) == TC_U32_ROOT)
294 		ht = rtnl_dereference(tp->root);
295 	else
296 		ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
297 
298 	if (!ht)
299 		return NULL;
300 
301 	if (TC_U32_KEY(handle) == 0)
302 		return ht;
303 
304 	return u32_lookup_key(ht, handle);
305 }
306 
307 /* Protected by rtnl lock */
gen_new_htid(struct tc_u_common * tp_c,struct tc_u_hnode * ptr)308 static u32 gen_new_htid(struct tc_u_common *tp_c, struct tc_u_hnode *ptr)
309 {
310 	int id = idr_alloc_cyclic(&tp_c->handle_idr, ptr, 1, 0x7FF, GFP_KERNEL);
311 	if (id < 0)
312 		return 0;
313 	return (id | 0x800U) << 20;
314 }
315 
316 static struct hlist_head *tc_u_common_hash;
317 
318 #define U32_HASH_SHIFT 10
319 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT)
320 
tc_u_common_ptr(const struct tcf_proto * tp)321 static void *tc_u_common_ptr(const struct tcf_proto *tp)
322 {
323 	struct tcf_block *block = tp->chain->block;
324 
325 	/* The block sharing is currently supported only
326 	 * for classless qdiscs. In that case we use block
327 	 * for tc_u_common identification. In case the
328 	 * block is not shared, block->q is a valid pointer
329 	 * and we can use that. That works for classful qdiscs.
330 	 */
331 	if (tcf_block_shared(block))
332 		return block;
333 	else
334 		return block->q;
335 }
336 
tc_u_hash(void * key)337 static struct hlist_head *tc_u_hash(void *key)
338 {
339 	return tc_u_common_hash + hash_ptr(key, U32_HASH_SHIFT);
340 }
341 
tc_u_common_find(void * key)342 static struct tc_u_common *tc_u_common_find(void *key)
343 {
344 	struct tc_u_common *tc;
345 	hlist_for_each_entry(tc, tc_u_hash(key), hnode) {
346 		if (tc->ptr == key)
347 			return tc;
348 	}
349 	return NULL;
350 }
351 
u32_init(struct tcf_proto * tp)352 static int u32_init(struct tcf_proto *tp)
353 {
354 	struct tc_u_hnode *root_ht;
355 	void *key = tc_u_common_ptr(tp);
356 	struct tc_u_common *tp_c = tc_u_common_find(key);
357 
358 	root_ht = kzalloc(struct_size(root_ht, ht, 1), GFP_KERNEL);
359 	if (root_ht == NULL)
360 		return -ENOBUFS;
361 
362 	root_ht->refcnt++;
363 	root_ht->handle = tp_c ? gen_new_htid(tp_c, root_ht) : 0x80000000;
364 	root_ht->prio = tp->prio;
365 	root_ht->is_root = true;
366 	idr_init(&root_ht->handle_idr);
367 
368 	if (tp_c == NULL) {
369 		tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
370 		if (tp_c == NULL) {
371 			kfree(root_ht);
372 			return -ENOBUFS;
373 		}
374 		tp_c->ptr = key;
375 		INIT_HLIST_NODE(&tp_c->hnode);
376 		idr_init(&tp_c->handle_idr);
377 
378 		hlist_add_head(&tp_c->hnode, tc_u_hash(key));
379 	}
380 
381 	tp_c->refcnt++;
382 	RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
383 	rcu_assign_pointer(tp_c->hlist, root_ht);
384 
385 	root_ht->refcnt++;
386 	rcu_assign_pointer(tp->root, root_ht);
387 	tp->data = tp_c;
388 	return 0;
389 }
390 
__u32_destroy_key(struct tc_u_knode * n)391 static void __u32_destroy_key(struct tc_u_knode *n)
392 {
393 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
394 
395 	tcf_exts_destroy(&n->exts);
396 	if (ht && --ht->refcnt == 0)
397 		kfree(ht);
398 	kfree(n);
399 }
400 
u32_destroy_key(struct tc_u_knode * n,bool free_pf)401 static void u32_destroy_key(struct tc_u_knode *n, bool free_pf)
402 {
403 	tcf_exts_put_net(&n->exts);
404 #ifdef CONFIG_CLS_U32_PERF
405 	if (free_pf)
406 		free_percpu(n->pf);
407 #endif
408 #ifdef CONFIG_CLS_U32_MARK
409 	if (free_pf)
410 		free_percpu(n->pcpu_success);
411 #endif
412 	__u32_destroy_key(n);
413 }
414 
415 /* u32_delete_key_rcu should be called when free'ing a copied
416  * version of a tc_u_knode obtained from u32_init_knode(). When
417  * copies are obtained from u32_init_knode() the statistics are
418  * shared between the old and new copies to allow readers to
419  * continue to update the statistics during the copy. To support
420  * this the u32_delete_key_rcu variant does not free the percpu
421  * statistics.
422  */
u32_delete_key_work(struct work_struct * work)423 static void u32_delete_key_work(struct work_struct *work)
424 {
425 	struct tc_u_knode *key = container_of(to_rcu_work(work),
426 					      struct tc_u_knode,
427 					      rwork);
428 	rtnl_lock();
429 	u32_destroy_key(key, false);
430 	rtnl_unlock();
431 }
432 
433 /* u32_delete_key_freepf_rcu is the rcu callback variant
434  * that free's the entire structure including the statistics
435  * percpu variables. Only use this if the key is not a copy
436  * returned by u32_init_knode(). See u32_delete_key_rcu()
437  * for the variant that should be used with keys return from
438  * u32_init_knode()
439  */
u32_delete_key_freepf_work(struct work_struct * work)440 static void u32_delete_key_freepf_work(struct work_struct *work)
441 {
442 	struct tc_u_knode *key = container_of(to_rcu_work(work),
443 					      struct tc_u_knode,
444 					      rwork);
445 	rtnl_lock();
446 	u32_destroy_key(key, true);
447 	rtnl_unlock();
448 }
449 
u32_delete_key(struct tcf_proto * tp,struct tc_u_knode * key)450 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
451 {
452 	struct tc_u_common *tp_c = tp->data;
453 	struct tc_u_knode __rcu **kp;
454 	struct tc_u_knode *pkp;
455 	struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
456 
457 	if (ht) {
458 		kp = &ht->ht[TC_U32_HASH(key->handle)];
459 		for (pkp = rtnl_dereference(*kp); pkp;
460 		     kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
461 			if (pkp == key) {
462 				RCU_INIT_POINTER(*kp, key->next);
463 				tp_c->knodes--;
464 
465 				tcf_unbind_filter(tp, &key->res);
466 				idr_remove(&ht->handle_idr, key->handle);
467 				tcf_exts_get_net(&key->exts);
468 				tcf_queue_work(&key->rwork, u32_delete_key_freepf_work);
469 				return 0;
470 			}
471 		}
472 	}
473 	WARN_ON(1);
474 	return 0;
475 }
476 
u32_clear_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h,struct netlink_ext_ack * extack)477 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
478 			       struct netlink_ext_ack *extack)
479 {
480 	struct tcf_block *block = tp->chain->block;
481 	struct tc_cls_u32_offload cls_u32 = {};
482 
483 	tc_cls_common_offload_init(&cls_u32.common, tp, h->flags, extack);
484 	cls_u32.command = TC_CLSU32_DELETE_HNODE;
485 	cls_u32.hnode.divisor = h->divisor;
486 	cls_u32.hnode.handle = h->handle;
487 	cls_u32.hnode.prio = h->prio;
488 
489 	tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, false, true);
490 }
491 
u32_replace_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h,u32 flags,struct netlink_ext_ack * extack)492 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
493 				u32 flags, struct netlink_ext_ack *extack)
494 {
495 	struct tcf_block *block = tp->chain->block;
496 	struct tc_cls_u32_offload cls_u32 = {};
497 	bool skip_sw = tc_skip_sw(flags);
498 	bool offloaded = false;
499 	int err;
500 
501 	tc_cls_common_offload_init(&cls_u32.common, tp, flags, extack);
502 	cls_u32.command = TC_CLSU32_NEW_HNODE;
503 	cls_u32.hnode.divisor = h->divisor;
504 	cls_u32.hnode.handle = h->handle;
505 	cls_u32.hnode.prio = h->prio;
506 
507 	err = tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, skip_sw, true);
508 	if (err < 0) {
509 		u32_clear_hw_hnode(tp, h, NULL);
510 		return err;
511 	} else if (err > 0) {
512 		offloaded = true;
513 	}
514 
515 	if (skip_sw && !offloaded)
516 		return -EINVAL;
517 
518 	return 0;
519 }
520 
u32_remove_hw_knode(struct tcf_proto * tp,struct tc_u_knode * n,struct netlink_ext_ack * extack)521 static void u32_remove_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
522 				struct netlink_ext_ack *extack)
523 {
524 	struct tcf_block *block = tp->chain->block;
525 	struct tc_cls_u32_offload cls_u32 = {};
526 
527 	tc_cls_common_offload_init(&cls_u32.common, tp, n->flags, extack);
528 	cls_u32.command = TC_CLSU32_DELETE_KNODE;
529 	cls_u32.knode.handle = n->handle;
530 
531 	tc_setup_cb_destroy(block, tp, TC_SETUP_CLSU32, &cls_u32, false,
532 			    &n->flags, &n->in_hw_count, true);
533 }
534 
u32_replace_hw_knode(struct tcf_proto * tp,struct tc_u_knode * n,u32 flags,struct netlink_ext_ack * extack)535 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
536 				u32 flags, struct netlink_ext_ack *extack)
537 {
538 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
539 	struct tcf_block *block = tp->chain->block;
540 	struct tc_cls_u32_offload cls_u32 = {};
541 	bool skip_sw = tc_skip_sw(flags);
542 	int err;
543 
544 	tc_cls_common_offload_init(&cls_u32.common, tp, flags, extack);
545 	cls_u32.command = TC_CLSU32_REPLACE_KNODE;
546 	cls_u32.knode.handle = n->handle;
547 	cls_u32.knode.fshift = n->fshift;
548 #ifdef CONFIG_CLS_U32_MARK
549 	cls_u32.knode.val = n->val;
550 	cls_u32.knode.mask = n->mask;
551 #else
552 	cls_u32.knode.val = 0;
553 	cls_u32.knode.mask = 0;
554 #endif
555 	cls_u32.knode.sel = &n->sel;
556 	cls_u32.knode.res = &n->res;
557 	cls_u32.knode.exts = &n->exts;
558 	if (n->ht_down)
559 		cls_u32.knode.link_handle = ht->handle;
560 
561 	err = tc_setup_cb_add(block, tp, TC_SETUP_CLSU32, &cls_u32, skip_sw,
562 			      &n->flags, &n->in_hw_count, true);
563 	if (err) {
564 		u32_remove_hw_knode(tp, n, NULL);
565 		return err;
566 	}
567 
568 	if (skip_sw && !(n->flags & TCA_CLS_FLAGS_IN_HW))
569 		return -EINVAL;
570 
571 	return 0;
572 }
573 
u32_clear_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht,struct netlink_ext_ack * extack)574 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
575 			    struct netlink_ext_ack *extack)
576 {
577 	struct tc_u_common *tp_c = tp->data;
578 	struct tc_u_knode *n;
579 	unsigned int h;
580 
581 	for (h = 0; h <= ht->divisor; h++) {
582 		while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
583 			RCU_INIT_POINTER(ht->ht[h],
584 					 rtnl_dereference(n->next));
585 			tp_c->knodes--;
586 			tcf_unbind_filter(tp, &n->res);
587 			u32_remove_hw_knode(tp, n, extack);
588 			idr_remove(&ht->handle_idr, n->handle);
589 			if (tcf_exts_get_net(&n->exts))
590 				tcf_queue_work(&n->rwork, u32_delete_key_freepf_work);
591 			else
592 				u32_destroy_key(n, true);
593 		}
594 	}
595 }
596 
u32_destroy_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht,struct netlink_ext_ack * extack)597 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
598 			     struct netlink_ext_ack *extack)
599 {
600 	struct tc_u_common *tp_c = tp->data;
601 	struct tc_u_hnode __rcu **hn;
602 	struct tc_u_hnode *phn;
603 
604 	WARN_ON(--ht->refcnt);
605 
606 	u32_clear_hnode(tp, ht, extack);
607 
608 	hn = &tp_c->hlist;
609 	for (phn = rtnl_dereference(*hn);
610 	     phn;
611 	     hn = &phn->next, phn = rtnl_dereference(*hn)) {
612 		if (phn == ht) {
613 			u32_clear_hw_hnode(tp, ht, extack);
614 			idr_destroy(&ht->handle_idr);
615 			idr_remove(&tp_c->handle_idr, ht->handle);
616 			RCU_INIT_POINTER(*hn, ht->next);
617 			kfree_rcu(ht, rcu);
618 			return 0;
619 		}
620 	}
621 
622 	return -ENOENT;
623 }
624 
u32_destroy(struct tcf_proto * tp,bool rtnl_held,struct netlink_ext_ack * extack)625 static void u32_destroy(struct tcf_proto *tp, bool rtnl_held,
626 			struct netlink_ext_ack *extack)
627 {
628 	struct tc_u_common *tp_c = tp->data;
629 	struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
630 
631 	WARN_ON(root_ht == NULL);
632 
633 	if (root_ht && --root_ht->refcnt == 1)
634 		u32_destroy_hnode(tp, root_ht, extack);
635 
636 	if (--tp_c->refcnt == 0) {
637 		struct tc_u_hnode *ht;
638 
639 		hlist_del(&tp_c->hnode);
640 
641 		while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
642 			u32_clear_hnode(tp, ht, extack);
643 			RCU_INIT_POINTER(tp_c->hlist, ht->next);
644 
645 			/* u32_destroy_key() will later free ht for us, if it's
646 			 * still referenced by some knode
647 			 */
648 			if (--ht->refcnt == 0)
649 				kfree_rcu(ht, rcu);
650 		}
651 
652 		idr_destroy(&tp_c->handle_idr);
653 		kfree(tp_c);
654 	}
655 
656 	tp->data = NULL;
657 }
658 
u32_delete(struct tcf_proto * tp,void * arg,bool * last,bool rtnl_held,struct netlink_ext_ack * extack)659 static int u32_delete(struct tcf_proto *tp, void *arg, bool *last,
660 		      bool rtnl_held, struct netlink_ext_ack *extack)
661 {
662 	struct tc_u_hnode *ht = arg;
663 	struct tc_u_common *tp_c = tp->data;
664 	int ret = 0;
665 
666 	if (TC_U32_KEY(ht->handle)) {
667 		u32_remove_hw_knode(tp, (struct tc_u_knode *)ht, extack);
668 		ret = u32_delete_key(tp, (struct tc_u_knode *)ht);
669 		goto out;
670 	}
671 
672 	if (ht->is_root) {
673 		NL_SET_ERR_MSG_MOD(extack, "Not allowed to delete root node");
674 		return -EINVAL;
675 	}
676 
677 	if (ht->refcnt == 1) {
678 		u32_destroy_hnode(tp, ht, extack);
679 	} else {
680 		NL_SET_ERR_MSG_MOD(extack, "Can not delete in-use filter");
681 		return -EBUSY;
682 	}
683 
684 out:
685 	*last = tp_c->refcnt == 1 && tp_c->knodes == 0;
686 	return ret;
687 }
688 
gen_new_kid(struct tc_u_hnode * ht,u32 htid)689 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 htid)
690 {
691 	u32 index = htid | 0x800;
692 	u32 max = htid | 0xFFF;
693 
694 	if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max, GFP_KERNEL)) {
695 		index = htid + 1;
696 		if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max,
697 				 GFP_KERNEL))
698 			index = max;
699 	}
700 
701 	return index;
702 }
703 
704 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
705 	[TCA_U32_CLASSID]	= { .type = NLA_U32 },
706 	[TCA_U32_HASH]		= { .type = NLA_U32 },
707 	[TCA_U32_LINK]		= { .type = NLA_U32 },
708 	[TCA_U32_DIVISOR]	= { .type = NLA_U32 },
709 	[TCA_U32_SEL]		= { .len = sizeof(struct tc_u32_sel) },
710 	[TCA_U32_INDEV]		= { .type = NLA_STRING, .len = IFNAMSIZ },
711 	[TCA_U32_MARK]		= { .len = sizeof(struct tc_u32_mark) },
712 	[TCA_U32_FLAGS]		= { .type = NLA_U32 },
713 };
714 
u32_unbind_filter(struct tcf_proto * tp,struct tc_u_knode * n,struct nlattr ** tb)715 static void u32_unbind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
716 			      struct nlattr **tb)
717 {
718 	if (tb[TCA_U32_CLASSID])
719 		tcf_unbind_filter(tp, &n->res);
720 }
721 
u32_bind_filter(struct tcf_proto * tp,struct tc_u_knode * n,unsigned long base,struct nlattr ** tb)722 static void u32_bind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
723 			    unsigned long base, struct nlattr **tb)
724 {
725 	if (tb[TCA_U32_CLASSID]) {
726 		n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
727 		tcf_bind_filter(tp, &n->res, base);
728 	}
729 }
730 
u32_set_parms(struct net * net,struct tcf_proto * tp,struct tc_u_knode * n,struct nlattr ** tb,struct nlattr * est,u32 flags,u32 fl_flags,struct netlink_ext_ack * extack)731 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
732 			 struct tc_u_knode *n, struct nlattr **tb,
733 			 struct nlattr *est, u32 flags, u32 fl_flags,
734 			 struct netlink_ext_ack *extack)
735 {
736 	int err, ifindex = -1;
737 
738 	err = tcf_exts_validate_ex(net, tp, tb, est, &n->exts, flags,
739 				   fl_flags, extack);
740 	if (err < 0)
741 		return err;
742 
743 	if (tb[TCA_U32_INDEV]) {
744 		ifindex = tcf_change_indev(net, tb[TCA_U32_INDEV], extack);
745 		if (ifindex < 0)
746 			return -EINVAL;
747 	}
748 
749 	if (tb[TCA_U32_LINK]) {
750 		u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
751 		struct tc_u_hnode *ht_down = NULL, *ht_old;
752 
753 		if (TC_U32_KEY(handle)) {
754 			NL_SET_ERR_MSG_MOD(extack, "u32 Link handle must be a hash table");
755 			return -EINVAL;
756 		}
757 
758 		if (handle) {
759 			ht_down = u32_lookup_ht(tp->data, handle);
760 
761 			if (!ht_down) {
762 				NL_SET_ERR_MSG_MOD(extack, "Link hash table not found");
763 				return -EINVAL;
764 			}
765 			if (ht_down->is_root) {
766 				NL_SET_ERR_MSG_MOD(extack, "Not linking to root node");
767 				return -EINVAL;
768 			}
769 			ht_down->refcnt++;
770 		}
771 
772 		ht_old = rtnl_dereference(n->ht_down);
773 		rcu_assign_pointer(n->ht_down, ht_down);
774 
775 		if (ht_old)
776 			ht_old->refcnt--;
777 	}
778 
779 	if (ifindex >= 0)
780 		n->ifindex = ifindex;
781 
782 	return 0;
783 }
784 
u32_replace_knode(struct tcf_proto * tp,struct tc_u_common * tp_c,struct tc_u_knode * n)785 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
786 			      struct tc_u_knode *n)
787 {
788 	struct tc_u_knode __rcu **ins;
789 	struct tc_u_knode *pins;
790 	struct tc_u_hnode *ht;
791 
792 	if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
793 		ht = rtnl_dereference(tp->root);
794 	else
795 		ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
796 
797 	ins = &ht->ht[TC_U32_HASH(n->handle)];
798 
799 	/* The node must always exist for it to be replaced if this is not the
800 	 * case then something went very wrong elsewhere.
801 	 */
802 	for (pins = rtnl_dereference(*ins); ;
803 	     ins = &pins->next, pins = rtnl_dereference(*ins))
804 		if (pins->handle == n->handle)
805 			break;
806 
807 	idr_replace(&ht->handle_idr, n, n->handle);
808 	RCU_INIT_POINTER(n->next, pins->next);
809 	rcu_assign_pointer(*ins, n);
810 }
811 
u32_init_knode(struct net * net,struct tcf_proto * tp,struct tc_u_knode * n)812 static struct tc_u_knode *u32_init_knode(struct net *net, struct tcf_proto *tp,
813 					 struct tc_u_knode *n)
814 {
815 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
816 	struct tc_u32_sel *s = &n->sel;
817 	struct tc_u_knode *new;
818 
819 	new = kzalloc(struct_size(new, sel.keys, s->nkeys), GFP_KERNEL);
820 	if (!new)
821 		return NULL;
822 
823 	RCU_INIT_POINTER(new->next, n->next);
824 	new->handle = n->handle;
825 	RCU_INIT_POINTER(new->ht_up, n->ht_up);
826 
827 	new->ifindex = n->ifindex;
828 	new->fshift = n->fshift;
829 	new->flags = n->flags;
830 	RCU_INIT_POINTER(new->ht_down, ht);
831 
832 #ifdef CONFIG_CLS_U32_PERF
833 	/* Statistics may be incremented by readers during update
834 	 * so we must keep them in tact. When the node is later destroyed
835 	 * a special destroy call must be made to not free the pf memory.
836 	 */
837 	new->pf = n->pf;
838 #endif
839 
840 #ifdef CONFIG_CLS_U32_MARK
841 	new->val = n->val;
842 	new->mask = n->mask;
843 	/* Similarly success statistics must be moved as pointers */
844 	new->pcpu_success = n->pcpu_success;
845 #endif
846 	memcpy(&new->sel, s, struct_size(s, keys, s->nkeys));
847 
848 	if (tcf_exts_init(&new->exts, net, TCA_U32_ACT, TCA_U32_POLICE)) {
849 		kfree(new);
850 		return NULL;
851 	}
852 
853 	/* bump reference count as long as we hold pointer to structure */
854 	if (ht)
855 		ht->refcnt++;
856 
857 	return new;
858 }
859 
u32_change(struct net * net,struct sk_buff * in_skb,struct tcf_proto * tp,unsigned long base,u32 handle,struct nlattr ** tca,void ** arg,u32 flags,struct netlink_ext_ack * extack)860 static int u32_change(struct net *net, struct sk_buff *in_skb,
861 		      struct tcf_proto *tp, unsigned long base, u32 handle,
862 		      struct nlattr **tca, void **arg, u32 flags,
863 		      struct netlink_ext_ack *extack)
864 {
865 	struct tc_u_common *tp_c = tp->data;
866 	struct tc_u_hnode *ht;
867 	struct tc_u_knode *n;
868 	struct tc_u32_sel *s;
869 	struct nlattr *opt = tca[TCA_OPTIONS];
870 	struct nlattr *tb[TCA_U32_MAX + 1];
871 	u32 htid, userflags = 0;
872 	size_t sel_size;
873 	int err;
874 
875 	if (!opt) {
876 		if (handle) {
877 			NL_SET_ERR_MSG_MOD(extack, "Filter handle requires options");
878 			return -EINVAL;
879 		} else {
880 			return 0;
881 		}
882 	}
883 
884 	err = nla_parse_nested_deprecated(tb, TCA_U32_MAX, opt, u32_policy,
885 					  extack);
886 	if (err < 0)
887 		return err;
888 
889 	if (tb[TCA_U32_FLAGS]) {
890 		userflags = nla_get_u32(tb[TCA_U32_FLAGS]);
891 		if (!tc_flags_valid(userflags)) {
892 			NL_SET_ERR_MSG_MOD(extack, "Invalid filter flags");
893 			return -EINVAL;
894 		}
895 	}
896 
897 	n = *arg;
898 	if (n) {
899 		struct tc_u_knode *new;
900 
901 		if (TC_U32_KEY(n->handle) == 0) {
902 			NL_SET_ERR_MSG_MOD(extack, "Key node id cannot be zero");
903 			return -EINVAL;
904 		}
905 
906 		if ((n->flags ^ userflags) &
907 		    ~(TCA_CLS_FLAGS_IN_HW | TCA_CLS_FLAGS_NOT_IN_HW)) {
908 			NL_SET_ERR_MSG_MOD(extack, "Key node flags do not match passed flags");
909 			return -EINVAL;
910 		}
911 
912 		new = u32_init_knode(net, tp, n);
913 		if (!new)
914 			return -ENOMEM;
915 
916 		err = u32_set_parms(net, tp, new, tb, tca[TCA_RATE],
917 				    flags, new->flags, extack);
918 
919 		if (err) {
920 			__u32_destroy_key(new);
921 			return err;
922 		}
923 
924 		u32_bind_filter(tp, new, base, tb);
925 
926 		err = u32_replace_hw_knode(tp, new, flags, extack);
927 		if (err) {
928 			u32_unbind_filter(tp, new, tb);
929 
930 			if (tb[TCA_U32_LINK]) {
931 				struct tc_u_hnode *ht_old;
932 
933 				ht_old = rtnl_dereference(n->ht_down);
934 				if (ht_old)
935 					ht_old->refcnt++;
936 			}
937 			__u32_destroy_key(new);
938 			return err;
939 		}
940 
941 		if (!tc_in_hw(new->flags))
942 			new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
943 
944 		u32_replace_knode(tp, tp_c, new);
945 		tcf_unbind_filter(tp, &n->res);
946 		tcf_exts_get_net(&n->exts);
947 		tcf_queue_work(&n->rwork, u32_delete_key_work);
948 		return 0;
949 	}
950 
951 	if (tb[TCA_U32_DIVISOR]) {
952 		unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
953 
954 		if (!is_power_of_2(divisor)) {
955 			NL_SET_ERR_MSG_MOD(extack, "Divisor is not a power of 2");
956 			return -EINVAL;
957 		}
958 		if (divisor-- > 0x100) {
959 			NL_SET_ERR_MSG_MOD(extack, "Exceeded maximum 256 hash buckets");
960 			return -EINVAL;
961 		}
962 		if (TC_U32_KEY(handle)) {
963 			NL_SET_ERR_MSG_MOD(extack, "Divisor can only be used on a hash table");
964 			return -EINVAL;
965 		}
966 		ht = kzalloc(struct_size(ht, ht, divisor + 1), GFP_KERNEL);
967 		if (ht == NULL)
968 			return -ENOBUFS;
969 		if (handle == 0) {
970 			handle = gen_new_htid(tp->data, ht);
971 			if (handle == 0) {
972 				kfree(ht);
973 				return -ENOMEM;
974 			}
975 		} else {
976 			err = idr_alloc_u32(&tp_c->handle_idr, ht, &handle,
977 					    handle, GFP_KERNEL);
978 			if (err) {
979 				kfree(ht);
980 				return err;
981 			}
982 		}
983 		ht->refcnt = 1;
984 		ht->divisor = divisor;
985 		ht->handle = handle;
986 		ht->prio = tp->prio;
987 		idr_init(&ht->handle_idr);
988 		ht->flags = userflags;
989 
990 		err = u32_replace_hw_hnode(tp, ht, userflags, extack);
991 		if (err) {
992 			idr_remove(&tp_c->handle_idr, handle);
993 			kfree(ht);
994 			return err;
995 		}
996 
997 		RCU_INIT_POINTER(ht->next, tp_c->hlist);
998 		rcu_assign_pointer(tp_c->hlist, ht);
999 		*arg = ht;
1000 
1001 		return 0;
1002 	}
1003 
1004 	if (tb[TCA_U32_HASH]) {
1005 		htid = nla_get_u32(tb[TCA_U32_HASH]);
1006 		if (TC_U32_HTID(htid) == TC_U32_ROOT) {
1007 			ht = rtnl_dereference(tp->root);
1008 			htid = ht->handle;
1009 		} else {
1010 			ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
1011 			if (!ht) {
1012 				NL_SET_ERR_MSG_MOD(extack, "Specified hash table not found");
1013 				return -EINVAL;
1014 			}
1015 		}
1016 	} else {
1017 		ht = rtnl_dereference(tp->root);
1018 		htid = ht->handle;
1019 	}
1020 
1021 	if (ht->divisor < TC_U32_HASH(htid)) {
1022 		NL_SET_ERR_MSG_MOD(extack, "Specified hash table buckets exceed configured value");
1023 		return -EINVAL;
1024 	}
1025 
1026 	/* At this point, we need to derive the new handle that will be used to
1027 	 * uniquely map the identity of this table match entry. The
1028 	 * identity of the entry that we need to construct is 32 bits made of:
1029 	 *     htid(12b):bucketid(8b):node/entryid(12b)
1030 	 *
1031 	 * At this point _we have the table(ht)_ in which we will insert this
1032 	 * entry. We carry the table's id in variable "htid".
1033 	 * Note that earlier code picked the ht selection either by a) the user
1034 	 * providing the htid specified via TCA_U32_HASH attribute or b) when
1035 	 * no such attribute is passed then the root ht, is default to at ID
1036 	 * 0x[800][00][000]. Rule: the root table has a single bucket with ID 0.
1037 	 * If OTOH the user passed us the htid, they may also pass a bucketid of
1038 	 * choice. 0 is fine. For example a user htid is 0x[600][01][000] it is
1039 	 * indicating hash bucketid of 1. Rule: the entry/node ID _cannot_ be
1040 	 * passed via the htid, so even if it was non-zero it will be ignored.
1041 	 *
1042 	 * We may also have a handle, if the user passed one. The handle also
1043 	 * carries the same addressing of htid(12b):bucketid(8b):node/entryid(12b).
1044 	 * Rule: the bucketid on the handle is ignored even if one was passed;
1045 	 * rather the value on "htid" is always assumed to be the bucketid.
1046 	 */
1047 	if (handle) {
1048 		/* Rule: The htid from handle and tableid from htid must match */
1049 		if (TC_U32_HTID(handle) && TC_U32_HTID(handle ^ htid)) {
1050 			NL_SET_ERR_MSG_MOD(extack, "Handle specified hash table address mismatch");
1051 			return -EINVAL;
1052 		}
1053 		/* Ok, so far we have a valid htid(12b):bucketid(8b) but we
1054 		 * need to finalize the table entry identification with the last
1055 		 * part - the node/entryid(12b)). Rule: Nodeid _cannot be 0_ for
1056 		 * entries. Rule: nodeid of 0 is reserved only for tables(see
1057 		 * earlier code which processes TC_U32_DIVISOR attribute).
1058 		 * Rule: The nodeid can only be derived from the handle (and not
1059 		 * htid).
1060 		 * Rule: if the handle specified zero for the node id example
1061 		 * 0x60000000, then pick a new nodeid from the pool of IDs
1062 		 * this hash table has been allocating from.
1063 		 * If OTOH it is specified (i.e for example the user passed a
1064 		 * handle such as 0x60000123), then we use it generate our final
1065 		 * handle which is used to uniquely identify the match entry.
1066 		 */
1067 		if (!TC_U32_NODE(handle)) {
1068 			handle = gen_new_kid(ht, htid);
1069 		} else {
1070 			handle = htid | TC_U32_NODE(handle);
1071 			err = idr_alloc_u32(&ht->handle_idr, NULL, &handle,
1072 					    handle, GFP_KERNEL);
1073 			if (err)
1074 				return err;
1075 		}
1076 	} else {
1077 		/* The user did not give us a handle; lets just generate one
1078 		 * from the table's pool of nodeids.
1079 		 */
1080 		handle = gen_new_kid(ht, htid);
1081 	}
1082 
1083 	if (tb[TCA_U32_SEL] == NULL) {
1084 		NL_SET_ERR_MSG_MOD(extack, "Selector not specified");
1085 		err = -EINVAL;
1086 		goto erridr;
1087 	}
1088 
1089 	s = nla_data(tb[TCA_U32_SEL]);
1090 	sel_size = struct_size(s, keys, s->nkeys);
1091 	if (nla_len(tb[TCA_U32_SEL]) < sel_size) {
1092 		err = -EINVAL;
1093 		goto erridr;
1094 	}
1095 
1096 	n = kzalloc(struct_size(n, sel.keys, s->nkeys), GFP_KERNEL);
1097 	if (n == NULL) {
1098 		err = -ENOBUFS;
1099 		goto erridr;
1100 	}
1101 
1102 #ifdef CONFIG_CLS_U32_PERF
1103 	n->pf = __alloc_percpu(struct_size(n->pf, kcnts, s->nkeys),
1104 			       __alignof__(struct tc_u32_pcnt));
1105 	if (!n->pf) {
1106 		err = -ENOBUFS;
1107 		goto errfree;
1108 	}
1109 #endif
1110 
1111 	unsafe_memcpy(&n->sel, s, sel_size,
1112 		      /* A composite flex-array structure destination,
1113 		       * which was correctly sized with struct_size(),
1114 		       * bounds-checked against nla_len(), and allocated
1115 		       * above. */);
1116 	RCU_INIT_POINTER(n->ht_up, ht);
1117 	n->handle = handle;
1118 	n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
1119 	n->flags = userflags;
1120 
1121 	err = tcf_exts_init(&n->exts, net, TCA_U32_ACT, TCA_U32_POLICE);
1122 	if (err < 0)
1123 		goto errout;
1124 
1125 #ifdef CONFIG_CLS_U32_MARK
1126 	n->pcpu_success = alloc_percpu(u32);
1127 	if (!n->pcpu_success) {
1128 		err = -ENOMEM;
1129 		goto errout;
1130 	}
1131 
1132 	if (tb[TCA_U32_MARK]) {
1133 		struct tc_u32_mark *mark;
1134 
1135 		mark = nla_data(tb[TCA_U32_MARK]);
1136 		n->val = mark->val;
1137 		n->mask = mark->mask;
1138 	}
1139 #endif
1140 
1141 	err = u32_set_parms(net, tp, n, tb, tca[TCA_RATE],
1142 			    flags, n->flags, extack);
1143 
1144 	u32_bind_filter(tp, n, base, tb);
1145 
1146 	if (err == 0) {
1147 		struct tc_u_knode __rcu **ins;
1148 		struct tc_u_knode *pins;
1149 
1150 		err = u32_replace_hw_knode(tp, n, flags, extack);
1151 		if (err)
1152 			goto errunbind;
1153 
1154 		if (!tc_in_hw(n->flags))
1155 			n->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
1156 
1157 		ins = &ht->ht[TC_U32_HASH(handle)];
1158 		for (pins = rtnl_dereference(*ins); pins;
1159 		     ins = &pins->next, pins = rtnl_dereference(*ins))
1160 			if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
1161 				break;
1162 
1163 		RCU_INIT_POINTER(n->next, pins);
1164 		rcu_assign_pointer(*ins, n);
1165 		tp_c->knodes++;
1166 		*arg = n;
1167 		return 0;
1168 	}
1169 
1170 errunbind:
1171 	u32_unbind_filter(tp, n, tb);
1172 
1173 #ifdef CONFIG_CLS_U32_MARK
1174 	free_percpu(n->pcpu_success);
1175 #endif
1176 
1177 errout:
1178 	tcf_exts_destroy(&n->exts);
1179 #ifdef CONFIG_CLS_U32_PERF
1180 errfree:
1181 	free_percpu(n->pf);
1182 #endif
1183 	kfree(n);
1184 erridr:
1185 	idr_remove(&ht->handle_idr, handle);
1186 	return err;
1187 }
1188 
u32_walk(struct tcf_proto * tp,struct tcf_walker * arg,bool rtnl_held)1189 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg,
1190 		     bool rtnl_held)
1191 {
1192 	struct tc_u_common *tp_c = tp->data;
1193 	struct tc_u_hnode *ht;
1194 	struct tc_u_knode *n;
1195 	unsigned int h;
1196 
1197 	if (arg->stop)
1198 		return;
1199 
1200 	for (ht = rtnl_dereference(tp_c->hlist);
1201 	     ht;
1202 	     ht = rtnl_dereference(ht->next)) {
1203 		if (ht->prio != tp->prio)
1204 			continue;
1205 
1206 		if (!tc_cls_stats_dump(tp, arg, ht))
1207 			return;
1208 
1209 		for (h = 0; h <= ht->divisor; h++) {
1210 			for (n = rtnl_dereference(ht->ht[h]);
1211 			     n;
1212 			     n = rtnl_dereference(n->next)) {
1213 				if (!tc_cls_stats_dump(tp, arg, n))
1214 					return;
1215 			}
1216 		}
1217 	}
1218 }
1219 
u32_reoffload_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht,bool add,flow_setup_cb_t * cb,void * cb_priv,struct netlink_ext_ack * extack)1220 static int u32_reoffload_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
1221 			       bool add, flow_setup_cb_t *cb, void *cb_priv,
1222 			       struct netlink_ext_ack *extack)
1223 {
1224 	struct tc_cls_u32_offload cls_u32 = {};
1225 	int err;
1226 
1227 	tc_cls_common_offload_init(&cls_u32.common, tp, ht->flags, extack);
1228 	cls_u32.command = add ? TC_CLSU32_NEW_HNODE : TC_CLSU32_DELETE_HNODE;
1229 	cls_u32.hnode.divisor = ht->divisor;
1230 	cls_u32.hnode.handle = ht->handle;
1231 	cls_u32.hnode.prio = ht->prio;
1232 
1233 	err = cb(TC_SETUP_CLSU32, &cls_u32, cb_priv);
1234 	if (err && add && tc_skip_sw(ht->flags))
1235 		return err;
1236 
1237 	return 0;
1238 }
1239 
u32_reoffload_knode(struct tcf_proto * tp,struct tc_u_knode * n,bool add,flow_setup_cb_t * cb,void * cb_priv,struct netlink_ext_ack * extack)1240 static int u32_reoffload_knode(struct tcf_proto *tp, struct tc_u_knode *n,
1241 			       bool add, flow_setup_cb_t *cb, void *cb_priv,
1242 			       struct netlink_ext_ack *extack)
1243 {
1244 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
1245 	struct tcf_block *block = tp->chain->block;
1246 	struct tc_cls_u32_offload cls_u32 = {};
1247 
1248 	tc_cls_common_offload_init(&cls_u32.common, tp, n->flags, extack);
1249 	cls_u32.command = add ?
1250 		TC_CLSU32_REPLACE_KNODE : TC_CLSU32_DELETE_KNODE;
1251 	cls_u32.knode.handle = n->handle;
1252 
1253 	if (add) {
1254 		cls_u32.knode.fshift = n->fshift;
1255 #ifdef CONFIG_CLS_U32_MARK
1256 		cls_u32.knode.val = n->val;
1257 		cls_u32.knode.mask = n->mask;
1258 #else
1259 		cls_u32.knode.val = 0;
1260 		cls_u32.knode.mask = 0;
1261 #endif
1262 		cls_u32.knode.sel = &n->sel;
1263 		cls_u32.knode.res = &n->res;
1264 		cls_u32.knode.exts = &n->exts;
1265 		if (n->ht_down)
1266 			cls_u32.knode.link_handle = ht->handle;
1267 	}
1268 
1269 	return tc_setup_cb_reoffload(block, tp, add, cb, TC_SETUP_CLSU32,
1270 				     &cls_u32, cb_priv, &n->flags,
1271 				     &n->in_hw_count);
1272 }
1273 
u32_reoffload(struct tcf_proto * tp,bool add,flow_setup_cb_t * cb,void * cb_priv,struct netlink_ext_ack * extack)1274 static int u32_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
1275 			 void *cb_priv, struct netlink_ext_ack *extack)
1276 {
1277 	struct tc_u_common *tp_c = tp->data;
1278 	struct tc_u_hnode *ht;
1279 	struct tc_u_knode *n;
1280 	unsigned int h;
1281 	int err;
1282 
1283 	for (ht = rtnl_dereference(tp_c->hlist);
1284 	     ht;
1285 	     ht = rtnl_dereference(ht->next)) {
1286 		if (ht->prio != tp->prio)
1287 			continue;
1288 
1289 		/* When adding filters to a new dev, try to offload the
1290 		 * hashtable first. When removing, do the filters before the
1291 		 * hashtable.
1292 		 */
1293 		if (add && !tc_skip_hw(ht->flags)) {
1294 			err = u32_reoffload_hnode(tp, ht, add, cb, cb_priv,
1295 						  extack);
1296 			if (err)
1297 				return err;
1298 		}
1299 
1300 		for (h = 0; h <= ht->divisor; h++) {
1301 			for (n = rtnl_dereference(ht->ht[h]);
1302 			     n;
1303 			     n = rtnl_dereference(n->next)) {
1304 				if (tc_skip_hw(n->flags))
1305 					continue;
1306 
1307 				err = u32_reoffload_knode(tp, n, add, cb,
1308 							  cb_priv, extack);
1309 				if (err)
1310 					return err;
1311 			}
1312 		}
1313 
1314 		if (!add && !tc_skip_hw(ht->flags))
1315 			u32_reoffload_hnode(tp, ht, add, cb, cb_priv, extack);
1316 	}
1317 
1318 	return 0;
1319 }
1320 
u32_bind_class(void * fh,u32 classid,unsigned long cl,void * q,unsigned long base)1321 static void u32_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
1322 			   unsigned long base)
1323 {
1324 	struct tc_u_knode *n = fh;
1325 
1326 	tc_cls_bind_class(classid, cl, q, &n->res, base);
1327 }
1328 
u32_dump(struct net * net,struct tcf_proto * tp,void * fh,struct sk_buff * skb,struct tcmsg * t,bool rtnl_held)1329 static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh,
1330 		    struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
1331 {
1332 	struct tc_u_knode *n = fh;
1333 	struct tc_u_hnode *ht_up, *ht_down;
1334 	struct nlattr *nest;
1335 
1336 	if (n == NULL)
1337 		return skb->len;
1338 
1339 	t->tcm_handle = n->handle;
1340 
1341 	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1342 	if (nest == NULL)
1343 		goto nla_put_failure;
1344 
1345 	if (TC_U32_KEY(n->handle) == 0) {
1346 		struct tc_u_hnode *ht = fh;
1347 		u32 divisor = ht->divisor + 1;
1348 
1349 		if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
1350 			goto nla_put_failure;
1351 	} else {
1352 #ifdef CONFIG_CLS_U32_PERF
1353 		struct tc_u32_pcnt *gpf;
1354 		int cpu;
1355 #endif
1356 
1357 		if (nla_put(skb, TCA_U32_SEL, struct_size(&n->sel, keys, n->sel.nkeys),
1358 			    &n->sel))
1359 			goto nla_put_failure;
1360 
1361 		ht_up = rtnl_dereference(n->ht_up);
1362 		if (ht_up) {
1363 			u32 htid = n->handle & 0xFFFFF000;
1364 			if (nla_put_u32(skb, TCA_U32_HASH, htid))
1365 				goto nla_put_failure;
1366 		}
1367 		if (n->res.classid &&
1368 		    nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
1369 			goto nla_put_failure;
1370 
1371 		ht_down = rtnl_dereference(n->ht_down);
1372 		if (ht_down &&
1373 		    nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
1374 			goto nla_put_failure;
1375 
1376 		if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
1377 			goto nla_put_failure;
1378 
1379 #ifdef CONFIG_CLS_U32_MARK
1380 		if ((n->val || n->mask)) {
1381 			struct tc_u32_mark mark = {.val = n->val,
1382 						   .mask = n->mask,
1383 						   .success = 0};
1384 			int cpum;
1385 
1386 			for_each_possible_cpu(cpum) {
1387 				__u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
1388 
1389 				mark.success += cnt;
1390 			}
1391 
1392 			if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
1393 				goto nla_put_failure;
1394 		}
1395 #endif
1396 
1397 		if (tcf_exts_dump(skb, &n->exts) < 0)
1398 			goto nla_put_failure;
1399 
1400 		if (n->ifindex) {
1401 			struct net_device *dev;
1402 			dev = __dev_get_by_index(net, n->ifindex);
1403 			if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1404 				goto nla_put_failure;
1405 		}
1406 #ifdef CONFIG_CLS_U32_PERF
1407 		gpf = kzalloc(struct_size(gpf, kcnts, n->sel.nkeys), GFP_KERNEL);
1408 		if (!gpf)
1409 			goto nla_put_failure;
1410 
1411 		for_each_possible_cpu(cpu) {
1412 			int i;
1413 			struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1414 
1415 			gpf->rcnt += pf->rcnt;
1416 			gpf->rhit += pf->rhit;
1417 			for (i = 0; i < n->sel.nkeys; i++)
1418 				gpf->kcnts[i] += pf->kcnts[i];
1419 		}
1420 
1421 		if (nla_put_64bit(skb, TCA_U32_PCNT, struct_size(gpf, kcnts, n->sel.nkeys),
1422 				  gpf, TCA_U32_PAD)) {
1423 			kfree(gpf);
1424 			goto nla_put_failure;
1425 		}
1426 		kfree(gpf);
1427 #endif
1428 	}
1429 
1430 	nla_nest_end(skb, nest);
1431 
1432 	if (TC_U32_KEY(n->handle))
1433 		if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1434 			goto nla_put_failure;
1435 	return skb->len;
1436 
1437 nla_put_failure:
1438 	nla_nest_cancel(skb, nest);
1439 	return -1;
1440 }
1441 
1442 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1443 	.kind		=	"u32",
1444 	.classify	=	u32_classify,
1445 	.init		=	u32_init,
1446 	.destroy	=	u32_destroy,
1447 	.get		=	u32_get,
1448 	.change		=	u32_change,
1449 	.delete		=	u32_delete,
1450 	.walk		=	u32_walk,
1451 	.reoffload	=	u32_reoffload,
1452 	.dump		=	u32_dump,
1453 	.bind_class	=	u32_bind_class,
1454 	.owner		=	THIS_MODULE,
1455 };
1456 
init_u32(void)1457 static int __init init_u32(void)
1458 {
1459 	int i, ret;
1460 
1461 	pr_info("u32 classifier\n");
1462 #ifdef CONFIG_CLS_U32_PERF
1463 	pr_info("    Performance counters on\n");
1464 #endif
1465 	pr_info("    input device check on\n");
1466 #ifdef CONFIG_NET_CLS_ACT
1467 	pr_info("    Actions configured\n");
1468 #endif
1469 	tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE,
1470 					  sizeof(struct hlist_head),
1471 					  GFP_KERNEL);
1472 	if (!tc_u_common_hash)
1473 		return -ENOMEM;
1474 
1475 	for (i = 0; i < U32_HASH_SIZE; i++)
1476 		INIT_HLIST_HEAD(&tc_u_common_hash[i]);
1477 
1478 	ret = register_tcf_proto_ops(&cls_u32_ops);
1479 	if (ret)
1480 		kvfree(tc_u_common_hash);
1481 	return ret;
1482 }
1483 
exit_u32(void)1484 static void __exit exit_u32(void)
1485 {
1486 	unregister_tcf_proto_ops(&cls_u32_ops);
1487 	kvfree(tc_u_common_hash);
1488 }
1489 
1490 module_init(init_u32)
1491 module_exit(exit_u32)
1492 MODULE_LICENSE("GPL");
1493