2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/etherdevice.h>
11 #include <linux/list.h>
12 #include <linux/random.h>
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15 #include <linux/string.h>
16 #include <net/mac80211.h>
18 #include "ieee80211_i.h"
21 #ifdef CONFIG_MAC80211_VERBOSE_MPATH_DEBUG
22 #define mpath_dbg(fmt, args...) printk(KERN_DEBUG fmt, ##args)
24 #define mpath_dbg(fmt, args...) do { (void)(0); } while (0)
27 /* There will be initially 2^INIT_PATHS_SIZE_ORDER buckets */
28 #define INIT_PATHS_SIZE_ORDER 2
30 /* Keep the mean chain length below this constant */
31 #define MEAN_CHAIN_LEN 2
33 #define MPATH_EXPIRED(mpath) ((mpath->flags & MESH_PATH_ACTIVE) && \
34 time_after(jiffies, mpath->exp_time) && \
35 !(mpath->flags & MESH_PATH_FIXED))
38 struct hlist_node list
;
40 /* This indirection allows two different tables to point to the same
41 * mesh_path structure, useful when resizing
43 struct mesh_path
*mpath
;
46 static struct mesh_table __rcu
*mesh_paths
;
47 static struct mesh_table __rcu
*mpp_paths
; /* Store paths for MPP&MAP */
49 int mesh_paths_generation
;
51 /* This lock will have the grow table function as writer and add / delete nodes
52 * as readers. RCU provides sufficient protection only when reading the table
53 * (i.e. doing lookups). Adding or adding or removing nodes requires we take
54 * the read lock or we risk operating on an old table. The write lock is only
55 * needed when modifying the number of buckets a table.
57 static DEFINE_RWLOCK(pathtbl_resize_lock
);
60 static inline struct mesh_table
*resize_dereference_mesh_paths(void)
62 return rcu_dereference_protected(mesh_paths
,
63 lockdep_is_held(&pathtbl_resize_lock
));
66 static inline struct mesh_table
*resize_dereference_mpp_paths(void)
68 return rcu_dereference_protected(mpp_paths
,
69 lockdep_is_held(&pathtbl_resize_lock
));
73 * CAREFUL -- "tbl" must not be an expression,
74 * in particular not an rcu_dereference(), since
75 * it's used twice. So it is illegal to do
76 * for_each_mesh_entry(rcu_dereference(...), ...)
78 #define for_each_mesh_entry(tbl, p, node, i) \
79 for (i = 0; i <= tbl->hash_mask; i++) \
80 hlist_for_each_entry_rcu(node, p, &tbl->hash_buckets[i], list)
83 static struct mesh_table
*mesh_table_alloc(int size_order
)
86 struct mesh_table
*newtbl
;
88 newtbl
= kmalloc(sizeof(struct mesh_table
), GFP_ATOMIC
);
92 newtbl
->hash_buckets
= kzalloc(sizeof(struct hlist_head
) *
93 (1 << size_order
), GFP_ATOMIC
);
95 if (!newtbl
->hash_buckets
) {
100 newtbl
->hashwlock
= kmalloc(sizeof(spinlock_t
) *
101 (1 << size_order
), GFP_ATOMIC
);
102 if (!newtbl
->hashwlock
) {
103 kfree(newtbl
->hash_buckets
);
108 newtbl
->size_order
= size_order
;
109 newtbl
->hash_mask
= (1 << size_order
) - 1;
110 atomic_set(&newtbl
->entries
, 0);
111 get_random_bytes(&newtbl
->hash_rnd
,
112 sizeof(newtbl
->hash_rnd
));
113 for (i
= 0; i
<= newtbl
->hash_mask
; i
++)
114 spin_lock_init(&newtbl
->hashwlock
[i
]);
115 spin_lock_init(&newtbl
->gates_lock
);
120 static void __mesh_table_free(struct mesh_table
*tbl
)
122 kfree(tbl
->hash_buckets
);
123 kfree(tbl
->hashwlock
);
127 static void mesh_table_free(struct mesh_table
*tbl
, bool free_leafs
)
129 struct hlist_head
*mesh_hash
;
130 struct hlist_node
*p
, *q
;
131 struct mpath_node
*gate
;
134 mesh_hash
= tbl
->hash_buckets
;
135 for (i
= 0; i
<= tbl
->hash_mask
; i
++) {
136 spin_lock_bh(&tbl
->hashwlock
[i
]);
137 hlist_for_each_safe(p
, q
, &mesh_hash
[i
]) {
138 tbl
->free_node(p
, free_leafs
);
139 atomic_dec(&tbl
->entries
);
141 spin_unlock_bh(&tbl
->hashwlock
[i
]);
144 spin_lock_bh(&tbl
->gates_lock
);
145 hlist_for_each_entry_safe(gate
, p
, q
,
146 tbl
->known_gates
, list
) {
147 hlist_del(&gate
->list
);
150 kfree(tbl
->known_gates
);
151 spin_unlock_bh(&tbl
->gates_lock
);
154 __mesh_table_free(tbl
);
157 static int mesh_table_grow(struct mesh_table
*oldtbl
,
158 struct mesh_table
*newtbl
)
160 struct hlist_head
*oldhash
;
161 struct hlist_node
*p
, *q
;
164 if (atomic_read(&oldtbl
->entries
)
165 < oldtbl
->mean_chain_len
* (oldtbl
->hash_mask
+ 1))
168 newtbl
->free_node
= oldtbl
->free_node
;
169 newtbl
->mean_chain_len
= oldtbl
->mean_chain_len
;
170 newtbl
->copy_node
= oldtbl
->copy_node
;
171 newtbl
->known_gates
= oldtbl
->known_gates
;
172 atomic_set(&newtbl
->entries
, atomic_read(&oldtbl
->entries
));
174 oldhash
= oldtbl
->hash_buckets
;
175 for (i
= 0; i
<= oldtbl
->hash_mask
; i
++)
176 hlist_for_each(p
, &oldhash
[i
])
177 if (oldtbl
->copy_node(p
, newtbl
) < 0)
183 for (i
= 0; i
<= newtbl
->hash_mask
; i
++) {
184 hlist_for_each_safe(p
, q
, &newtbl
->hash_buckets
[i
])
185 oldtbl
->free_node(p
, 0);
190 static u32
mesh_table_hash(u8
*addr
, struct ieee80211_sub_if_data
*sdata
,
191 struct mesh_table
*tbl
)
193 /* Use last four bytes of hw addr and interface index as hash index */
194 return jhash_2words(*(u32
*)(addr
+2), sdata
->dev
->ifindex
, tbl
->hash_rnd
)
201 * mesh_path_assign_nexthop - update mesh path next hop
203 * @mpath: mesh path to update
204 * @sta: next hop to assign
206 * Locking: mpath->state_lock must be held when calling this function
208 void mesh_path_assign_nexthop(struct mesh_path
*mpath
, struct sta_info
*sta
)
211 struct ieee80211_hdr
*hdr
;
212 struct sk_buff_head tmpq
;
215 rcu_assign_pointer(mpath
->next_hop
, sta
);
217 __skb_queue_head_init(&tmpq
);
219 spin_lock_irqsave(&mpath
->frame_queue
.lock
, flags
);
221 while ((skb
= __skb_dequeue(&mpath
->frame_queue
)) != NULL
) {
222 hdr
= (struct ieee80211_hdr
*) skb
->data
;
223 memcpy(hdr
->addr1
, sta
->sta
.addr
, ETH_ALEN
);
224 memcpy(hdr
->addr2
, mpath
->sdata
->vif
.addr
, ETH_ALEN
);
225 __skb_queue_tail(&tmpq
, skb
);
228 skb_queue_splice(&tmpq
, &mpath
->frame_queue
);
229 spin_unlock_irqrestore(&mpath
->frame_queue
.lock
, flags
);
232 static void prepare_for_gate(struct sk_buff
*skb
, char *dst_addr
,
233 struct mesh_path
*gate_mpath
)
235 struct ieee80211_hdr
*hdr
;
236 struct ieee80211s_hdr
*mshdr
;
237 int mesh_hdrlen
, hdrlen
;
240 hdr
= (struct ieee80211_hdr
*) skb
->data
;
241 hdrlen
= ieee80211_hdrlen(hdr
->frame_control
);
242 mshdr
= (struct ieee80211s_hdr
*) (skb
->data
+ hdrlen
);
244 if (!(mshdr
->flags
& MESH_FLAGS_AE
)) {
245 /* size of the fixed part of the mesh header */
248 /* make room for the two extended addresses */
249 skb_push(skb
, 2 * ETH_ALEN
);
250 memmove(skb
->data
, hdr
, hdrlen
+ mesh_hdrlen
);
252 hdr
= (struct ieee80211_hdr
*) skb
->data
;
254 /* we preserve the previous mesh header and only add
255 * the new addreses */
256 mshdr
= (struct ieee80211s_hdr
*) (skb
->data
+ hdrlen
);
257 mshdr
->flags
= MESH_FLAGS_AE_A5_A6
;
258 memcpy(mshdr
->eaddr1
, hdr
->addr3
, ETH_ALEN
);
259 memcpy(mshdr
->eaddr2
, hdr
->addr4
, ETH_ALEN
);
262 /* update next hop */
263 hdr
= (struct ieee80211_hdr
*) skb
->data
;
265 next_hop
= rcu_dereference(gate_mpath
->next_hop
)->sta
.addr
;
266 memcpy(hdr
->addr1
, next_hop
, ETH_ALEN
);
268 memcpy(hdr
->addr2
, gate_mpath
->sdata
->vif
.addr
, ETH_ALEN
);
269 memcpy(hdr
->addr3
, dst_addr
, ETH_ALEN
);
274 * mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
276 * This function is used to transfer or copy frames from an unresolved mpath to
277 * a gate mpath. The function also adds the Address Extension field and
278 * updates the next hop.
280 * If a frame already has an Address Extension field, only the next hop and
281 * destination addresses are updated.
283 * The gate mpath must be an active mpath with a valid mpath->next_hop.
285 * @mpath: An active mpath the frames will be sent to (i.e. the gate)
286 * @from_mpath: The failed mpath
287 * @copy: When true, copy all the frames to the new mpath queue. When false,
290 static void mesh_path_move_to_queue(struct mesh_path
*gate_mpath
,
291 struct mesh_path
*from_mpath
,
294 struct sk_buff
*skb
, *cp_skb
= NULL
;
295 struct sk_buff_head gateq
, failq
;
299 BUG_ON(gate_mpath
== from_mpath
);
300 BUG_ON(!gate_mpath
->next_hop
);
302 __skb_queue_head_init(&gateq
);
303 __skb_queue_head_init(&failq
);
305 spin_lock_irqsave(&from_mpath
->frame_queue
.lock
, flags
);
306 skb_queue_splice_init(&from_mpath
->frame_queue
, &failq
);
307 spin_unlock_irqrestore(&from_mpath
->frame_queue
.lock
, flags
);
309 num_skbs
= skb_queue_len(&failq
);
312 skb
= __skb_dequeue(&failq
);
314 cp_skb
= skb_copy(skb
, GFP_ATOMIC
);
316 __skb_queue_tail(&failq
, cp_skb
);
319 prepare_for_gate(skb
, gate_mpath
->dst
, gate_mpath
);
320 __skb_queue_tail(&gateq
, skb
);
323 spin_lock_irqsave(&gate_mpath
->frame_queue
.lock
, flags
);
324 skb_queue_splice(&gateq
, &gate_mpath
->frame_queue
);
325 mpath_dbg("Mpath queue for gate %pM has %d frames\n",
327 skb_queue_len(&gate_mpath
->frame_queue
));
328 spin_unlock_irqrestore(&gate_mpath
->frame_queue
.lock
, flags
);
333 spin_lock_irqsave(&from_mpath
->frame_queue
.lock
, flags
);
334 skb_queue_splice(&failq
, &from_mpath
->frame_queue
);
335 spin_unlock_irqrestore(&from_mpath
->frame_queue
.lock
, flags
);
339 static struct mesh_path
*mpath_lookup(struct mesh_table
*tbl
, u8
*dst
,
340 struct ieee80211_sub_if_data
*sdata
)
342 struct mesh_path
*mpath
;
343 struct hlist_node
*n
;
344 struct hlist_head
*bucket
;
345 struct mpath_node
*node
;
347 bucket
= &tbl
->hash_buckets
[mesh_table_hash(dst
, sdata
, tbl
)];
348 hlist_for_each_entry_rcu(node
, n
, bucket
, list
) {
350 if (mpath
->sdata
== sdata
&&
351 compare_ether_addr(dst
, mpath
->dst
) == 0) {
352 if (MPATH_EXPIRED(mpath
)) {
353 spin_lock_bh(&mpath
->state_lock
);
354 mpath
->flags
&= ~MESH_PATH_ACTIVE
;
355 spin_unlock_bh(&mpath
->state_lock
);
364 * mesh_path_lookup - look up a path in the mesh path table
365 * @dst: hardware address (ETH_ALEN length) of destination
366 * @sdata: local subif
368 * Returns: pointer to the mesh path structure, or NULL if not found
370 * Locking: must be called within a read rcu section.
372 struct mesh_path
*mesh_path_lookup(u8
*dst
, struct ieee80211_sub_if_data
*sdata
)
374 return mpath_lookup(rcu_dereference(mesh_paths
), dst
, sdata
);
377 struct mesh_path
*mpp_path_lookup(u8
*dst
, struct ieee80211_sub_if_data
*sdata
)
379 return mpath_lookup(rcu_dereference(mpp_paths
), dst
, sdata
);
384 * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
386 * @sdata: local subif, or NULL for all entries
388 * Returns: pointer to the mesh path structure, or NULL if not found.
390 * Locking: must be called within a read rcu section.
392 struct mesh_path
*mesh_path_lookup_by_idx(int idx
, struct ieee80211_sub_if_data
*sdata
)
394 struct mesh_table
*tbl
= rcu_dereference(mesh_paths
);
395 struct mpath_node
*node
;
396 struct hlist_node
*p
;
400 for_each_mesh_entry(tbl
, p
, node
, i
) {
401 if (sdata
&& node
->mpath
->sdata
!= sdata
)
404 if (MPATH_EXPIRED(node
->mpath
)) {
405 spin_lock_bh(&node
->mpath
->state_lock
);
406 node
->mpath
->flags
&= ~MESH_PATH_ACTIVE
;
407 spin_unlock_bh(&node
->mpath
->state_lock
);
417 * mesh_path_add_gate - add the given mpath to a mesh gate to our path table
418 * @mpath: gate path to add to table
420 int mesh_path_add_gate(struct mesh_path
*mpath
)
422 struct mesh_table
*tbl
;
423 struct mpath_node
*gate
, *new_gate
;
424 struct hlist_node
*n
;
428 tbl
= rcu_dereference(mesh_paths
);
430 hlist_for_each_entry_rcu(gate
, n
, tbl
->known_gates
, list
)
431 if (gate
->mpath
== mpath
) {
436 new_gate
= kzalloc(sizeof(struct mpath_node
), GFP_ATOMIC
);
442 mpath
->is_gate
= true;
443 mpath
->sdata
->u
.mesh
.num_gates
++;
444 new_gate
->mpath
= mpath
;
445 spin_lock_bh(&tbl
->gates_lock
);
446 hlist_add_head_rcu(&new_gate
->list
, tbl
->known_gates
);
447 spin_unlock_bh(&tbl
->gates_lock
);
449 mpath_dbg("Mesh path (%s): Recorded new gate: %pM. %d known gates\n",
450 mpath
->sdata
->name
, mpath
->dst
,
451 mpath
->sdata
->u
.mesh
.num_gates
);
459 * mesh_gate_del - remove a mesh gate from the list of known gates
460 * @tbl: table which holds our list of known gates
463 * Returns: 0 on success
465 * Locking: must be called inside rcu_read_lock() section
467 static int mesh_gate_del(struct mesh_table
*tbl
, struct mesh_path
*mpath
)
469 struct mpath_node
*gate
;
470 struct hlist_node
*p
, *q
;
472 hlist_for_each_entry_safe(gate
, p
, q
, tbl
->known_gates
, list
)
473 if (gate
->mpath
== mpath
) {
474 spin_lock_bh(&tbl
->gates_lock
);
475 hlist_del_rcu(&gate
->list
);
476 kfree_rcu(gate
, rcu
);
477 spin_unlock_bh(&tbl
->gates_lock
);
478 mpath
->sdata
->u
.mesh
.num_gates
--;
479 mpath
->is_gate
= false;
480 mpath_dbg("Mesh path (%s): Deleted gate: %pM. "
481 "%d known gates\n", mpath
->sdata
->name
,
482 mpath
->dst
, mpath
->sdata
->u
.mesh
.num_gates
);
490 * mesh_gate_num - number of gates known to this interface
493 int mesh_gate_num(struct ieee80211_sub_if_data
*sdata
)
495 return sdata
->u
.mesh
.num_gates
;
499 * mesh_path_add - allocate and add a new path to the mesh path table
500 * @addr: destination address of the path (ETH_ALEN length)
501 * @sdata: local subif
503 * Returns: 0 on success
505 * State: the initial state of the new path is set to 0
507 int mesh_path_add(u8
*dst
, struct ieee80211_sub_if_data
*sdata
)
509 struct ieee80211_if_mesh
*ifmsh
= &sdata
->u
.mesh
;
510 struct ieee80211_local
*local
= sdata
->local
;
511 struct mesh_table
*tbl
;
512 struct mesh_path
*mpath
, *new_mpath
;
513 struct mpath_node
*node
, *new_node
;
514 struct hlist_head
*bucket
;
515 struct hlist_node
*n
;
520 if (compare_ether_addr(dst
, sdata
->vif
.addr
) == 0)
521 /* never add ourselves as neighbours */
524 if (is_multicast_ether_addr(dst
))
527 if (atomic_add_unless(&sdata
->u
.mesh
.mpaths
, 1, MESH_MAX_MPATHS
) == 0)
531 new_mpath
= kzalloc(sizeof(struct mesh_path
), GFP_ATOMIC
);
535 new_node
= kmalloc(sizeof(struct mpath_node
), GFP_ATOMIC
);
539 read_lock_bh(&pathtbl_resize_lock
);
540 memcpy(new_mpath
->dst
, dst
, ETH_ALEN
);
541 memset(new_mpath
->rann_snd_addr
, 0xff, ETH_ALEN
);
542 new_mpath
->is_root
= false;
543 new_mpath
->sdata
= sdata
;
544 new_mpath
->flags
= 0;
545 skb_queue_head_init(&new_mpath
->frame_queue
);
546 new_node
->mpath
= new_mpath
;
547 new_mpath
->timer
.data
= (unsigned long) new_mpath
;
548 new_mpath
->timer
.function
= mesh_path_timer
;
549 new_mpath
->exp_time
= jiffies
;
550 spin_lock_init(&new_mpath
->state_lock
);
551 init_timer(&new_mpath
->timer
);
553 tbl
= resize_dereference_mesh_paths();
555 hash_idx
= mesh_table_hash(dst
, sdata
, tbl
);
556 bucket
= &tbl
->hash_buckets
[hash_idx
];
558 spin_lock(&tbl
->hashwlock
[hash_idx
]);
561 hlist_for_each_entry(node
, n
, bucket
, list
) {
563 if (mpath
->sdata
== sdata
&&
564 compare_ether_addr(dst
, mpath
->dst
) == 0)
568 hlist_add_head_rcu(&new_node
->list
, bucket
);
569 if (atomic_inc_return(&tbl
->entries
) >=
570 tbl
->mean_chain_len
* (tbl
->hash_mask
+ 1))
573 mesh_paths_generation
++;
575 spin_unlock(&tbl
->hashwlock
[hash_idx
]);
576 read_unlock_bh(&pathtbl_resize_lock
);
578 set_bit(MESH_WORK_GROW_MPATH_TABLE
, &ifmsh
->wrkq_flags
);
579 ieee80211_queue_work(&local
->hw
, &sdata
->work
);
584 spin_unlock(&tbl
->hashwlock
[hash_idx
]);
585 read_unlock_bh(&pathtbl_resize_lock
);
590 atomic_dec(&sdata
->u
.mesh
.mpaths
);
594 static void mesh_table_free_rcu(struct rcu_head
*rcu
)
596 struct mesh_table
*tbl
= container_of(rcu
, struct mesh_table
, rcu_head
);
598 mesh_table_free(tbl
, false);
601 void mesh_mpath_table_grow(void)
603 struct mesh_table
*oldtbl
, *newtbl
;
605 write_lock_bh(&pathtbl_resize_lock
);
606 oldtbl
= resize_dereference_mesh_paths();
607 newtbl
= mesh_table_alloc(oldtbl
->size_order
+ 1);
610 if (mesh_table_grow(oldtbl
, newtbl
) < 0) {
611 __mesh_table_free(newtbl
);
614 rcu_assign_pointer(mesh_paths
, newtbl
);
616 call_rcu(&oldtbl
->rcu_head
, mesh_table_free_rcu
);
619 write_unlock_bh(&pathtbl_resize_lock
);
622 void mesh_mpp_table_grow(void)
624 struct mesh_table
*oldtbl
, *newtbl
;
626 write_lock_bh(&pathtbl_resize_lock
);
627 oldtbl
= resize_dereference_mpp_paths();
628 newtbl
= mesh_table_alloc(oldtbl
->size_order
+ 1);
631 if (mesh_table_grow(oldtbl
, newtbl
) < 0) {
632 __mesh_table_free(newtbl
);
635 rcu_assign_pointer(mpp_paths
, newtbl
);
636 call_rcu(&oldtbl
->rcu_head
, mesh_table_free_rcu
);
639 write_unlock_bh(&pathtbl_resize_lock
);
642 int mpp_path_add(u8
*dst
, u8
*mpp
, struct ieee80211_sub_if_data
*sdata
)
644 struct ieee80211_if_mesh
*ifmsh
= &sdata
->u
.mesh
;
645 struct ieee80211_local
*local
= sdata
->local
;
646 struct mesh_table
*tbl
;
647 struct mesh_path
*mpath
, *new_mpath
;
648 struct mpath_node
*node
, *new_node
;
649 struct hlist_head
*bucket
;
650 struct hlist_node
*n
;
655 if (compare_ether_addr(dst
, sdata
->vif
.addr
) == 0)
656 /* never add ourselves as neighbours */
659 if (is_multicast_ether_addr(dst
))
663 new_mpath
= kzalloc(sizeof(struct mesh_path
), GFP_ATOMIC
);
667 new_node
= kmalloc(sizeof(struct mpath_node
), GFP_ATOMIC
);
671 read_lock_bh(&pathtbl_resize_lock
);
672 memcpy(new_mpath
->dst
, dst
, ETH_ALEN
);
673 memcpy(new_mpath
->mpp
, mpp
, ETH_ALEN
);
674 new_mpath
->sdata
= sdata
;
675 new_mpath
->flags
= 0;
676 skb_queue_head_init(&new_mpath
->frame_queue
);
677 new_node
->mpath
= new_mpath
;
678 init_timer(&new_mpath
->timer
);
679 new_mpath
->exp_time
= jiffies
;
680 spin_lock_init(&new_mpath
->state_lock
);
682 tbl
= resize_dereference_mpp_paths();
684 hash_idx
= mesh_table_hash(dst
, sdata
, tbl
);
685 bucket
= &tbl
->hash_buckets
[hash_idx
];
687 spin_lock(&tbl
->hashwlock
[hash_idx
]);
690 hlist_for_each_entry(node
, n
, bucket
, list
) {
692 if (mpath
->sdata
== sdata
&&
693 compare_ether_addr(dst
, mpath
->dst
) == 0)
697 hlist_add_head_rcu(&new_node
->list
, bucket
);
698 if (atomic_inc_return(&tbl
->entries
) >=
699 tbl
->mean_chain_len
* (tbl
->hash_mask
+ 1))
702 spin_unlock(&tbl
->hashwlock
[hash_idx
]);
703 read_unlock_bh(&pathtbl_resize_lock
);
705 set_bit(MESH_WORK_GROW_MPP_TABLE
, &ifmsh
->wrkq_flags
);
706 ieee80211_queue_work(&local
->hw
, &sdata
->work
);
711 spin_unlock(&tbl
->hashwlock
[hash_idx
]);
712 read_unlock_bh(&pathtbl_resize_lock
);
722 * mesh_plink_broken - deactivates paths and sends perr when a link breaks
724 * @sta: broken peer link
726 * This function must be called from the rate control algorithm if enough
727 * delivery errors suggest that a peer link is no longer usable.
729 void mesh_plink_broken(struct sta_info
*sta
)
731 struct mesh_table
*tbl
;
732 static const u8 bcast
[ETH_ALEN
] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
733 struct mesh_path
*mpath
;
734 struct mpath_node
*node
;
735 struct hlist_node
*p
;
736 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
738 __le16 reason
= cpu_to_le16(WLAN_REASON_MESH_PATH_DEST_UNREACHABLE
);
741 tbl
= rcu_dereference(mesh_paths
);
742 for_each_mesh_entry(tbl
, p
, node
, i
) {
744 if (rcu_dereference(mpath
->next_hop
) == sta
&&
745 mpath
->flags
& MESH_PATH_ACTIVE
&&
746 !(mpath
->flags
& MESH_PATH_FIXED
)) {
747 spin_lock_bh(&mpath
->state_lock
);
748 mpath
->flags
&= ~MESH_PATH_ACTIVE
;
750 spin_unlock_bh(&mpath
->state_lock
);
751 mesh_path_error_tx(sdata
->u
.mesh
.mshcfg
.element_ttl
,
752 mpath
->dst
, cpu_to_le32(mpath
->sn
),
753 reason
, bcast
, sdata
);
759 static void mesh_path_node_reclaim(struct rcu_head
*rp
)
761 struct mpath_node
*node
= container_of(rp
, struct mpath_node
, rcu
);
762 struct ieee80211_sub_if_data
*sdata
= node
->mpath
->sdata
;
764 del_timer_sync(&node
->mpath
->timer
);
765 atomic_dec(&sdata
->u
.mesh
.mpaths
);
770 /* needs to be called with the corresponding hashwlock taken */
771 static void __mesh_path_del(struct mesh_table
*tbl
, struct mpath_node
*node
)
773 struct mesh_path
*mpath
;
775 spin_lock(&mpath
->state_lock
);
776 mpath
->flags
|= MESH_PATH_RESOLVING
;
778 mesh_gate_del(tbl
, mpath
);
779 hlist_del_rcu(&node
->list
);
780 call_rcu(&node
->rcu
, mesh_path_node_reclaim
);
781 spin_unlock(&mpath
->state_lock
);
782 atomic_dec(&tbl
->entries
);
786 * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
788 * @sta - mesh peer to match
790 * RCU notes: this function is called when a mesh plink transitions from
791 * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
792 * allows path creation. This will happen before the sta can be freed (because
793 * sta_info_destroy() calls this) so any reader in a rcu read block will be
794 * protected against the plink disappearing.
796 void mesh_path_flush_by_nexthop(struct sta_info
*sta
)
798 struct mesh_table
*tbl
;
799 struct mesh_path
*mpath
;
800 struct mpath_node
*node
;
801 struct hlist_node
*p
;
805 read_lock_bh(&pathtbl_resize_lock
);
806 tbl
= resize_dereference_mesh_paths();
807 for_each_mesh_entry(tbl
, p
, node
, i
) {
809 if (rcu_dereference(mpath
->next_hop
) == sta
) {
810 spin_lock(&tbl
->hashwlock
[i
]);
811 __mesh_path_del(tbl
, node
);
812 spin_unlock(&tbl
->hashwlock
[i
]);
815 read_unlock_bh(&pathtbl_resize_lock
);
819 static void table_flush_by_iface(struct mesh_table
*tbl
,
820 struct ieee80211_sub_if_data
*sdata
)
822 struct mesh_path
*mpath
;
823 struct mpath_node
*node
;
824 struct hlist_node
*p
;
827 WARN_ON(!rcu_read_lock_held());
828 for_each_mesh_entry(tbl
, p
, node
, i
) {
830 if (mpath
->sdata
!= sdata
)
832 spin_lock_bh(&tbl
->hashwlock
[i
]);
833 __mesh_path_del(tbl
, node
);
834 spin_unlock_bh(&tbl
->hashwlock
[i
]);
839 * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
841 * This function deletes both mesh paths as well as mesh portal paths.
843 * @sdata - interface data to match
846 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data
*sdata
)
848 struct mesh_table
*tbl
;
851 read_lock_bh(&pathtbl_resize_lock
);
852 tbl
= resize_dereference_mesh_paths();
853 table_flush_by_iface(tbl
, sdata
);
854 tbl
= resize_dereference_mpp_paths();
855 table_flush_by_iface(tbl
, sdata
);
856 read_unlock_bh(&pathtbl_resize_lock
);
861 * mesh_path_del - delete a mesh path from the table
863 * @addr: dst address (ETH_ALEN length)
864 * @sdata: local subif
866 * Returns: 0 if successful
868 int mesh_path_del(u8
*addr
, struct ieee80211_sub_if_data
*sdata
)
870 struct mesh_table
*tbl
;
871 struct mesh_path
*mpath
;
872 struct mpath_node
*node
;
873 struct hlist_head
*bucket
;
874 struct hlist_node
*n
;
878 read_lock_bh(&pathtbl_resize_lock
);
879 tbl
= resize_dereference_mesh_paths();
880 hash_idx
= mesh_table_hash(addr
, sdata
, tbl
);
881 bucket
= &tbl
->hash_buckets
[hash_idx
];
883 spin_lock(&tbl
->hashwlock
[hash_idx
]);
884 hlist_for_each_entry(node
, n
, bucket
, list
) {
886 if (mpath
->sdata
== sdata
&&
887 compare_ether_addr(addr
, mpath
->dst
) == 0) {
888 __mesh_path_del(tbl
, node
);
895 mesh_paths_generation
++;
896 spin_unlock(&tbl
->hashwlock
[hash_idx
]);
897 read_unlock_bh(&pathtbl_resize_lock
);
902 * mesh_path_tx_pending - sends pending frames in a mesh path queue
904 * @mpath: mesh path to activate
906 * Locking: the state_lock of the mpath structure must NOT be held when calling
909 void mesh_path_tx_pending(struct mesh_path
*mpath
)
911 if (mpath
->flags
& MESH_PATH_ACTIVE
)
912 ieee80211_add_pending_skbs(mpath
->sdata
->local
,
913 &mpath
->frame_queue
);
917 * mesh_path_send_to_gates - sends pending frames to all known mesh gates
919 * @mpath: mesh path whose queue will be emptied
921 * If there is only one gate, the frames are transferred from the failed mpath
922 * queue to that gate's queue. If there are more than one gates, the frames
923 * are copied from each gate to the next. After frames are copied, the
924 * mpath queues are emptied onto the transmission queue.
926 int mesh_path_send_to_gates(struct mesh_path
*mpath
)
928 struct ieee80211_sub_if_data
*sdata
= mpath
->sdata
;
929 struct hlist_node
*n
;
930 struct mesh_table
*tbl
;
931 struct mesh_path
*from_mpath
= mpath
;
932 struct mpath_node
*gate
= NULL
;
934 struct hlist_head
*known_gates
;
937 tbl
= rcu_dereference(mesh_paths
);
938 known_gates
= tbl
->known_gates
;
942 return -EHOSTUNREACH
;
944 hlist_for_each_entry_rcu(gate
, n
, known_gates
, list
) {
945 if (gate
->mpath
->sdata
!= sdata
)
948 if (gate
->mpath
->flags
& MESH_PATH_ACTIVE
) {
949 mpath_dbg("Forwarding to %pM\n", gate
->mpath
->dst
);
950 mesh_path_move_to_queue(gate
->mpath
, from_mpath
, copy
);
951 from_mpath
= gate
->mpath
;
954 mpath_dbg("Not forwarding %p\n", gate
->mpath
);
955 mpath_dbg("flags %x\n", gate
->mpath
->flags
);
959 hlist_for_each_entry_rcu(gate
, n
, known_gates
, list
)
960 if (gate
->mpath
->sdata
== sdata
) {
961 mpath_dbg("Sending to %pM\n", gate
->mpath
->dst
);
962 mesh_path_tx_pending(gate
->mpath
);
965 return (from_mpath
== mpath
) ? -EHOSTUNREACH
: 0;
969 * mesh_path_discard_frame - discard a frame whose path could not be resolved
971 * @skb: frame to discard
972 * @sdata: network subif the frame was to be sent through
974 * Locking: the function must me called within a rcu_read_lock region
976 void mesh_path_discard_frame(struct sk_buff
*skb
,
977 struct ieee80211_sub_if_data
*sdata
)
980 sdata
->u
.mesh
.mshstats
.dropped_frames_no_route
++;
984 * mesh_path_flush_pending - free the pending queue of a mesh path
986 * @mpath: mesh path whose queue has to be freed
988 * Locking: the function must me called within a rcu_read_lock region
990 void mesh_path_flush_pending(struct mesh_path
*mpath
)
994 while ((skb
= skb_dequeue(&mpath
->frame_queue
)) != NULL
)
995 mesh_path_discard_frame(skb
, mpath
->sdata
);
999 * mesh_path_fix_nexthop - force a specific next hop for a mesh path
1001 * @mpath: the mesh path to modify
1002 * @next_hop: the next hop to force
1004 * Locking: this function must be called holding mpath->state_lock
1006 void mesh_path_fix_nexthop(struct mesh_path
*mpath
, struct sta_info
*next_hop
)
1008 spin_lock_bh(&mpath
->state_lock
);
1009 mesh_path_assign_nexthop(mpath
, next_hop
);
1012 mpath
->hop_count
= 0;
1013 mpath
->exp_time
= 0;
1014 mpath
->flags
|= MESH_PATH_FIXED
;
1015 mesh_path_activate(mpath
);
1016 spin_unlock_bh(&mpath
->state_lock
);
1017 mesh_path_tx_pending(mpath
);
1020 static void mesh_path_node_free(struct hlist_node
*p
, bool free_leafs
)
1022 struct mesh_path
*mpath
;
1023 struct mpath_node
*node
= hlist_entry(p
, struct mpath_node
, list
);
1024 mpath
= node
->mpath
;
1027 del_timer_sync(&mpath
->timer
);
1033 static int mesh_path_node_copy(struct hlist_node
*p
, struct mesh_table
*newtbl
)
1035 struct mesh_path
*mpath
;
1036 struct mpath_node
*node
, *new_node
;
1039 new_node
= kmalloc(sizeof(struct mpath_node
), GFP_ATOMIC
);
1040 if (new_node
== NULL
)
1043 node
= hlist_entry(p
, struct mpath_node
, list
);
1044 mpath
= node
->mpath
;
1045 new_node
->mpath
= mpath
;
1046 hash_idx
= mesh_table_hash(mpath
->dst
, mpath
->sdata
, newtbl
);
1047 hlist_add_head(&new_node
->list
,
1048 &newtbl
->hash_buckets
[hash_idx
]);
1052 int mesh_pathtbl_init(void)
1054 struct mesh_table
*tbl_path
, *tbl_mpp
;
1057 tbl_path
= mesh_table_alloc(INIT_PATHS_SIZE_ORDER
);
1060 tbl_path
->free_node
= &mesh_path_node_free
;
1061 tbl_path
->copy_node
= &mesh_path_node_copy
;
1062 tbl_path
->mean_chain_len
= MEAN_CHAIN_LEN
;
1063 tbl_path
->known_gates
= kzalloc(sizeof(struct hlist_head
), GFP_ATOMIC
);
1064 if (!tbl_path
->known_gates
) {
1068 INIT_HLIST_HEAD(tbl_path
->known_gates
);
1071 tbl_mpp
= mesh_table_alloc(INIT_PATHS_SIZE_ORDER
);
1076 tbl_mpp
->free_node
= &mesh_path_node_free
;
1077 tbl_mpp
->copy_node
= &mesh_path_node_copy
;
1078 tbl_mpp
->mean_chain_len
= MEAN_CHAIN_LEN
;
1079 tbl_mpp
->known_gates
= kzalloc(sizeof(struct hlist_head
), GFP_ATOMIC
);
1080 if (!tbl_mpp
->known_gates
) {
1084 INIT_HLIST_HEAD(tbl_mpp
->known_gates
);
1086 /* Need no locking since this is during init */
1087 RCU_INIT_POINTER(mesh_paths
, tbl_path
);
1088 RCU_INIT_POINTER(mpp_paths
, tbl_mpp
);
1093 mesh_table_free(tbl_mpp
, true);
1095 mesh_table_free(tbl_path
, true);
1099 void mesh_path_expire(struct ieee80211_sub_if_data
*sdata
)
1101 struct mesh_table
*tbl
;
1102 struct mesh_path
*mpath
;
1103 struct mpath_node
*node
;
1104 struct hlist_node
*p
;
1108 tbl
= rcu_dereference(mesh_paths
);
1109 for_each_mesh_entry(tbl
, p
, node
, i
) {
1110 if (node
->mpath
->sdata
!= sdata
)
1112 mpath
= node
->mpath
;
1113 if ((!(mpath
->flags
& MESH_PATH_RESOLVING
)) &&
1114 (!(mpath
->flags
& MESH_PATH_FIXED
)) &&
1115 time_after(jiffies
, mpath
->exp_time
+ MESH_PATH_EXPIRE
))
1116 mesh_path_del(mpath
->dst
, mpath
->sdata
);
1121 void mesh_pathtbl_unregister(void)
1123 /* no need for locking during exit path */
1124 mesh_table_free(rcu_dereference_protected(mesh_paths
, 1), true);
1125 mesh_table_free(rcu_dereference_protected(mpp_paths
, 1), true);