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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 00:40:03 +00:00
![Tom Herbert](/assets/img/avatar_default.png)
Most callers of rhashtable_walk_start don't care about a resize event which is indicated by a return value of -EAGAIN. So calls to rhashtable_walk_start are wrapped wih code to ignore -EAGAIN. Something like this is common: ret = rhashtable_walk_start(rhiter); if (ret && ret != -EAGAIN) goto out; Since zero and -EAGAIN are the only possible return values from the function this check is pointless. The condition never evaluates to true. This patch changes rhashtable_walk_start to return void. This simplifies code for the callers that ignore -EAGAIN. For the few cases where the caller cares about the resize event, particularly where the table can be walked in mulitple parts for netlink or seq file dump, the function rhashtable_walk_start_check has been added that returns -EAGAIN on a resize event. Signed-off-by: Tom Herbert <tom@quantonium.net> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
891 lines
22 KiB
C
891 lines
22 KiB
C
/*
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* Copyright (c) 2008, 2009 open80211s Ltd.
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* Author: Luis Carlos Cobo <luisca@cozybit.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/etherdevice.h>
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#include <linux/list.h>
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#include <linux/random.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/string.h>
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#include <net/mac80211.h>
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#include "wme.h"
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#include "ieee80211_i.h"
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#include "mesh.h"
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static void mesh_path_free_rcu(struct mesh_table *tbl, struct mesh_path *mpath);
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static u32 mesh_table_hash(const void *addr, u32 len, u32 seed)
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{
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/* Use last four bytes of hw addr as hash index */
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return jhash_1word(*(u32 *)(addr+2), seed);
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}
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static const struct rhashtable_params mesh_rht_params = {
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.nelem_hint = 2,
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.automatic_shrinking = true,
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.key_len = ETH_ALEN,
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.key_offset = offsetof(struct mesh_path, dst),
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.head_offset = offsetof(struct mesh_path, rhash),
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.hashfn = mesh_table_hash,
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};
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static inline bool mpath_expired(struct mesh_path *mpath)
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{
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return (mpath->flags & MESH_PATH_ACTIVE) &&
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time_after(jiffies, mpath->exp_time) &&
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!(mpath->flags & MESH_PATH_FIXED);
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}
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static void mesh_path_rht_free(void *ptr, void *tblptr)
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{
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struct mesh_path *mpath = ptr;
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struct mesh_table *tbl = tblptr;
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mesh_path_free_rcu(tbl, mpath);
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}
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static struct mesh_table *mesh_table_alloc(void)
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{
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struct mesh_table *newtbl;
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newtbl = kmalloc(sizeof(struct mesh_table), GFP_ATOMIC);
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if (!newtbl)
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return NULL;
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INIT_HLIST_HEAD(&newtbl->known_gates);
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atomic_set(&newtbl->entries, 0);
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spin_lock_init(&newtbl->gates_lock);
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return newtbl;
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}
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static void mesh_table_free(struct mesh_table *tbl)
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{
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rhashtable_free_and_destroy(&tbl->rhead,
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mesh_path_rht_free, tbl);
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kfree(tbl);
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}
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/**
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*
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* mesh_path_assign_nexthop - update mesh path next hop
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*
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* @mpath: mesh path to update
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* @sta: next hop to assign
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*
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* Locking: mpath->state_lock must be held when calling this function
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*/
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void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
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{
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struct sk_buff *skb;
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struct ieee80211_hdr *hdr;
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unsigned long flags;
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rcu_assign_pointer(mpath->next_hop, sta);
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spin_lock_irqsave(&mpath->frame_queue.lock, flags);
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skb_queue_walk(&mpath->frame_queue, skb) {
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hdr = (struct ieee80211_hdr *) skb->data;
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memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
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memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
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ieee80211_mps_set_frame_flags(sta->sdata, sta, hdr);
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}
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spin_unlock_irqrestore(&mpath->frame_queue.lock, flags);
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}
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static void prepare_for_gate(struct sk_buff *skb, char *dst_addr,
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struct mesh_path *gate_mpath)
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{
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struct ieee80211_hdr *hdr;
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struct ieee80211s_hdr *mshdr;
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int mesh_hdrlen, hdrlen;
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char *next_hop;
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hdr = (struct ieee80211_hdr *) skb->data;
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hdrlen = ieee80211_hdrlen(hdr->frame_control);
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mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
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if (!(mshdr->flags & MESH_FLAGS_AE)) {
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/* size of the fixed part of the mesh header */
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mesh_hdrlen = 6;
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/* make room for the two extended addresses */
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skb_push(skb, 2 * ETH_ALEN);
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memmove(skb->data, hdr, hdrlen + mesh_hdrlen);
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hdr = (struct ieee80211_hdr *) skb->data;
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/* we preserve the previous mesh header and only add
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* the new addreses */
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mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
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mshdr->flags = MESH_FLAGS_AE_A5_A6;
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memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN);
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memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN);
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}
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/* update next hop */
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hdr = (struct ieee80211_hdr *) skb->data;
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rcu_read_lock();
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next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr;
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memcpy(hdr->addr1, next_hop, ETH_ALEN);
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rcu_read_unlock();
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memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN);
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memcpy(hdr->addr3, dst_addr, ETH_ALEN);
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}
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/**
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*
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* mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
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*
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* This function is used to transfer or copy frames from an unresolved mpath to
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* a gate mpath. The function also adds the Address Extension field and
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* updates the next hop.
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*
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* If a frame already has an Address Extension field, only the next hop and
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* destination addresses are updated.
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*
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* The gate mpath must be an active mpath with a valid mpath->next_hop.
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*
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* @mpath: An active mpath the frames will be sent to (i.e. the gate)
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* @from_mpath: The failed mpath
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* @copy: When true, copy all the frames to the new mpath queue. When false,
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* move them.
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*/
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static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
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struct mesh_path *from_mpath,
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bool copy)
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{
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struct sk_buff *skb, *fskb, *tmp;
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struct sk_buff_head failq;
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unsigned long flags;
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if (WARN_ON(gate_mpath == from_mpath))
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return;
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if (WARN_ON(!gate_mpath->next_hop))
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return;
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__skb_queue_head_init(&failq);
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spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
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skb_queue_splice_init(&from_mpath->frame_queue, &failq);
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spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
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skb_queue_walk_safe(&failq, fskb, tmp) {
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if (skb_queue_len(&gate_mpath->frame_queue) >=
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MESH_FRAME_QUEUE_LEN) {
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mpath_dbg(gate_mpath->sdata, "mpath queue full!\n");
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break;
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}
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skb = skb_copy(fskb, GFP_ATOMIC);
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if (WARN_ON(!skb))
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break;
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prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
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skb_queue_tail(&gate_mpath->frame_queue, skb);
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if (copy)
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continue;
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__skb_unlink(fskb, &failq);
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kfree_skb(fskb);
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}
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mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n",
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gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue));
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if (!copy)
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return;
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spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
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skb_queue_splice(&failq, &from_mpath->frame_queue);
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spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
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}
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static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
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struct ieee80211_sub_if_data *sdata)
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{
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struct mesh_path *mpath;
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mpath = rhashtable_lookup_fast(&tbl->rhead, dst, mesh_rht_params);
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if (mpath && mpath_expired(mpath)) {
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spin_lock_bh(&mpath->state_lock);
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mpath->flags &= ~MESH_PATH_ACTIVE;
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spin_unlock_bh(&mpath->state_lock);
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}
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return mpath;
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}
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/**
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* mesh_path_lookup - look up a path in the mesh path table
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* @sdata: local subif
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* @dst: hardware address (ETH_ALEN length) of destination
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*
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* Returns: pointer to the mesh path structure, or NULL if not found
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*
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* Locking: must be called within a read rcu section.
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*/
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struct mesh_path *
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mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
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{
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return mpath_lookup(sdata->u.mesh.mesh_paths, dst, sdata);
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}
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struct mesh_path *
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mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
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{
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return mpath_lookup(sdata->u.mesh.mpp_paths, dst, sdata);
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}
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static struct mesh_path *
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__mesh_path_lookup_by_idx(struct mesh_table *tbl, int idx)
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{
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int i = 0, ret;
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struct mesh_path *mpath = NULL;
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struct rhashtable_iter iter;
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ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
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if (ret)
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return NULL;
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rhashtable_walk_start(&iter);
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while ((mpath = rhashtable_walk_next(&iter))) {
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if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
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continue;
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if (IS_ERR(mpath))
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break;
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if (i++ == idx)
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break;
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}
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rhashtable_walk_stop(&iter);
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rhashtable_walk_exit(&iter);
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if (IS_ERR(mpath) || !mpath)
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return NULL;
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if (mpath_expired(mpath)) {
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spin_lock_bh(&mpath->state_lock);
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mpath->flags &= ~MESH_PATH_ACTIVE;
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spin_unlock_bh(&mpath->state_lock);
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}
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return mpath;
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}
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/**
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* mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
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* @idx: index
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* @sdata: local subif, or NULL for all entries
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*
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* Returns: pointer to the mesh path structure, or NULL if not found.
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*
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* Locking: must be called within a read rcu section.
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*/
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struct mesh_path *
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mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
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{
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return __mesh_path_lookup_by_idx(sdata->u.mesh.mesh_paths, idx);
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}
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/**
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* mpp_path_lookup_by_idx - look up a path in the proxy path table by its index
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* @idx: index
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* @sdata: local subif, or NULL for all entries
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*
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* Returns: pointer to the proxy path structure, or NULL if not found.
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*
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* Locking: must be called within a read rcu section.
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*/
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struct mesh_path *
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mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
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{
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return __mesh_path_lookup_by_idx(sdata->u.mesh.mpp_paths, idx);
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}
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/**
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* mesh_path_add_gate - add the given mpath to a mesh gate to our path table
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* @mpath: gate path to add to table
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*/
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int mesh_path_add_gate(struct mesh_path *mpath)
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{
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struct mesh_table *tbl;
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int err;
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rcu_read_lock();
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tbl = mpath->sdata->u.mesh.mesh_paths;
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spin_lock_bh(&mpath->state_lock);
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if (mpath->is_gate) {
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err = -EEXIST;
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spin_unlock_bh(&mpath->state_lock);
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goto err_rcu;
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}
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mpath->is_gate = true;
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mpath->sdata->u.mesh.num_gates++;
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spin_lock(&tbl->gates_lock);
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hlist_add_head_rcu(&mpath->gate_list, &tbl->known_gates);
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spin_unlock(&tbl->gates_lock);
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spin_unlock_bh(&mpath->state_lock);
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mpath_dbg(mpath->sdata,
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"Mesh path: Recorded new gate: %pM. %d known gates\n",
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mpath->dst, mpath->sdata->u.mesh.num_gates);
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err = 0;
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err_rcu:
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rcu_read_unlock();
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return err;
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}
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/**
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* mesh_gate_del - remove a mesh gate from the list of known gates
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* @tbl: table which holds our list of known gates
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* @mpath: gate mpath
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*/
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static void mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
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{
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lockdep_assert_held(&mpath->state_lock);
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if (!mpath->is_gate)
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return;
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mpath->is_gate = false;
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spin_lock_bh(&tbl->gates_lock);
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hlist_del_rcu(&mpath->gate_list);
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mpath->sdata->u.mesh.num_gates--;
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spin_unlock_bh(&tbl->gates_lock);
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mpath_dbg(mpath->sdata,
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"Mesh path: Deleted gate: %pM. %d known gates\n",
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mpath->dst, mpath->sdata->u.mesh.num_gates);
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}
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/**
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* mesh_gate_num - number of gates known to this interface
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* @sdata: subif data
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*/
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int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
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{
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return sdata->u.mesh.num_gates;
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}
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static
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struct mesh_path *mesh_path_new(struct ieee80211_sub_if_data *sdata,
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const u8 *dst, gfp_t gfp_flags)
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{
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struct mesh_path *new_mpath;
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new_mpath = kzalloc(sizeof(struct mesh_path), gfp_flags);
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if (!new_mpath)
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return NULL;
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memcpy(new_mpath->dst, dst, ETH_ALEN);
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eth_broadcast_addr(new_mpath->rann_snd_addr);
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new_mpath->is_root = false;
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new_mpath->sdata = sdata;
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new_mpath->flags = 0;
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skb_queue_head_init(&new_mpath->frame_queue);
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new_mpath->exp_time = jiffies;
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spin_lock_init(&new_mpath->state_lock);
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timer_setup(&new_mpath->timer, mesh_path_timer, 0);
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return new_mpath;
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}
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/**
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* mesh_path_add - allocate and add a new path to the mesh path table
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* @dst: destination address of the path (ETH_ALEN length)
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* @sdata: local subif
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*
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* Returns: 0 on success
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*
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* State: the initial state of the new path is set to 0
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*/
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struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
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const u8 *dst)
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{
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struct mesh_table *tbl;
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struct mesh_path *mpath, *new_mpath;
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int ret;
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if (ether_addr_equal(dst, sdata->vif.addr))
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/* never add ourselves as neighbours */
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return ERR_PTR(-ENOTSUPP);
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if (is_multicast_ether_addr(dst))
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return ERR_PTR(-ENOTSUPP);
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if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
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return ERR_PTR(-ENOSPC);
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new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
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if (!new_mpath)
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return ERR_PTR(-ENOMEM);
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tbl = sdata->u.mesh.mesh_paths;
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do {
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ret = rhashtable_lookup_insert_fast(&tbl->rhead,
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&new_mpath->rhash,
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mesh_rht_params);
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if (ret == -EEXIST)
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mpath = rhashtable_lookup_fast(&tbl->rhead,
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dst,
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mesh_rht_params);
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} while (unlikely(ret == -EEXIST && !mpath));
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if (ret && ret != -EEXIST)
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return ERR_PTR(ret);
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/* At this point either new_mpath was added, or we found a
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* matching entry already in the table; in the latter case
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* free the unnecessary new entry.
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*/
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if (ret == -EEXIST) {
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kfree(new_mpath);
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new_mpath = mpath;
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}
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sdata->u.mesh.mesh_paths_generation++;
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return new_mpath;
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}
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int mpp_path_add(struct ieee80211_sub_if_data *sdata,
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const u8 *dst, const u8 *mpp)
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{
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struct mesh_table *tbl;
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struct mesh_path *new_mpath;
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int ret;
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if (ether_addr_equal(dst, sdata->vif.addr))
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/* never add ourselves as neighbours */
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return -ENOTSUPP;
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if (is_multicast_ether_addr(dst))
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return -ENOTSUPP;
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new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
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if (!new_mpath)
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return -ENOMEM;
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memcpy(new_mpath->mpp, mpp, ETH_ALEN);
|
|
tbl = sdata->u.mesh.mpp_paths;
|
|
ret = rhashtable_lookup_insert_fast(&tbl->rhead,
|
|
&new_mpath->rhash,
|
|
mesh_rht_params);
|
|
|
|
sdata->u.mesh.mpp_paths_generation++;
|
|
return ret;
|
|
}
|
|
|
|
|
|
/**
|
|
* mesh_plink_broken - deactivates paths and sends perr when a link breaks
|
|
*
|
|
* @sta: broken peer link
|
|
*
|
|
* This function must be called from the rate control algorithm if enough
|
|
* delivery errors suggest that a peer link is no longer usable.
|
|
*/
|
|
void mesh_plink_broken(struct sta_info *sta)
|
|
{
|
|
struct ieee80211_sub_if_data *sdata = sta->sdata;
|
|
struct mesh_table *tbl = sdata->u.mesh.mesh_paths;
|
|
static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
|
|
struct mesh_path *mpath;
|
|
struct rhashtable_iter iter;
|
|
int ret;
|
|
|
|
ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
|
|
if (ret)
|
|
return;
|
|
|
|
rhashtable_walk_start(&iter);
|
|
|
|
while ((mpath = rhashtable_walk_next(&iter))) {
|
|
if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
|
|
continue;
|
|
if (IS_ERR(mpath))
|
|
break;
|
|
if (rcu_access_pointer(mpath->next_hop) == sta &&
|
|
mpath->flags & MESH_PATH_ACTIVE &&
|
|
!(mpath->flags & MESH_PATH_FIXED)) {
|
|
spin_lock_bh(&mpath->state_lock);
|
|
mpath->flags &= ~MESH_PATH_ACTIVE;
|
|
++mpath->sn;
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
mesh_path_error_tx(sdata,
|
|
sdata->u.mesh.mshcfg.element_ttl,
|
|
mpath->dst, mpath->sn,
|
|
WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, bcast);
|
|
}
|
|
}
|
|
rhashtable_walk_stop(&iter);
|
|
rhashtable_walk_exit(&iter);
|
|
}
|
|
|
|
static void mesh_path_free_rcu(struct mesh_table *tbl,
|
|
struct mesh_path *mpath)
|
|
{
|
|
struct ieee80211_sub_if_data *sdata = mpath->sdata;
|
|
|
|
spin_lock_bh(&mpath->state_lock);
|
|
mpath->flags |= MESH_PATH_RESOLVING | MESH_PATH_DELETED;
|
|
mesh_gate_del(tbl, mpath);
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
del_timer_sync(&mpath->timer);
|
|
atomic_dec(&sdata->u.mesh.mpaths);
|
|
atomic_dec(&tbl->entries);
|
|
kfree_rcu(mpath, rcu);
|
|
}
|
|
|
|
static void __mesh_path_del(struct mesh_table *tbl, struct mesh_path *mpath)
|
|
{
|
|
rhashtable_remove_fast(&tbl->rhead, &mpath->rhash, mesh_rht_params);
|
|
mesh_path_free_rcu(tbl, mpath);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
|
|
*
|
|
* @sta: mesh peer to match
|
|
*
|
|
* RCU notes: this function is called when a mesh plink transitions from
|
|
* PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
|
|
* allows path creation. This will happen before the sta can be freed (because
|
|
* sta_info_destroy() calls this) so any reader in a rcu read block will be
|
|
* protected against the plink disappearing.
|
|
*/
|
|
void mesh_path_flush_by_nexthop(struct sta_info *sta)
|
|
{
|
|
struct ieee80211_sub_if_data *sdata = sta->sdata;
|
|
struct mesh_table *tbl = sdata->u.mesh.mesh_paths;
|
|
struct mesh_path *mpath;
|
|
struct rhashtable_iter iter;
|
|
int ret;
|
|
|
|
ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
|
|
if (ret)
|
|
return;
|
|
|
|
rhashtable_walk_start(&iter);
|
|
|
|
while ((mpath = rhashtable_walk_next(&iter))) {
|
|
if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
|
|
continue;
|
|
if (IS_ERR(mpath))
|
|
break;
|
|
|
|
if (rcu_access_pointer(mpath->next_hop) == sta)
|
|
__mesh_path_del(tbl, mpath);
|
|
}
|
|
|
|
rhashtable_walk_stop(&iter);
|
|
rhashtable_walk_exit(&iter);
|
|
}
|
|
|
|
static void mpp_flush_by_proxy(struct ieee80211_sub_if_data *sdata,
|
|
const u8 *proxy)
|
|
{
|
|
struct mesh_table *tbl = sdata->u.mesh.mpp_paths;
|
|
struct mesh_path *mpath;
|
|
struct rhashtable_iter iter;
|
|
int ret;
|
|
|
|
ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
|
|
if (ret)
|
|
return;
|
|
|
|
rhashtable_walk_start(&iter);
|
|
|
|
while ((mpath = rhashtable_walk_next(&iter))) {
|
|
if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
|
|
continue;
|
|
if (IS_ERR(mpath))
|
|
break;
|
|
|
|
if (ether_addr_equal(mpath->mpp, proxy))
|
|
__mesh_path_del(tbl, mpath);
|
|
}
|
|
|
|
rhashtable_walk_stop(&iter);
|
|
rhashtable_walk_exit(&iter);
|
|
}
|
|
|
|
static void table_flush_by_iface(struct mesh_table *tbl)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct rhashtable_iter iter;
|
|
int ret;
|
|
|
|
ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_ATOMIC);
|
|
if (ret)
|
|
return;
|
|
|
|
rhashtable_walk_start(&iter);
|
|
|
|
while ((mpath = rhashtable_walk_next(&iter))) {
|
|
if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
|
|
continue;
|
|
if (IS_ERR(mpath))
|
|
break;
|
|
__mesh_path_del(tbl, mpath);
|
|
}
|
|
|
|
rhashtable_walk_stop(&iter);
|
|
rhashtable_walk_exit(&iter);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
|
|
*
|
|
* This function deletes both mesh paths as well as mesh portal paths.
|
|
*
|
|
* @sdata: interface data to match
|
|
*
|
|
*/
|
|
void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
table_flush_by_iface(sdata->u.mesh.mesh_paths);
|
|
table_flush_by_iface(sdata->u.mesh.mpp_paths);
|
|
}
|
|
|
|
/**
|
|
* table_path_del - delete a path from the mesh or mpp table
|
|
*
|
|
* @tbl: mesh or mpp path table
|
|
* @sdata: local subif
|
|
* @addr: dst address (ETH_ALEN length)
|
|
*
|
|
* Returns: 0 if successful
|
|
*/
|
|
static int table_path_del(struct mesh_table *tbl,
|
|
struct ieee80211_sub_if_data *sdata,
|
|
const u8 *addr)
|
|
{
|
|
struct mesh_path *mpath;
|
|
|
|
rcu_read_lock();
|
|
mpath = rhashtable_lookup_fast(&tbl->rhead, addr, mesh_rht_params);
|
|
if (!mpath) {
|
|
rcu_read_unlock();
|
|
return -ENXIO;
|
|
}
|
|
|
|
__mesh_path_del(tbl, mpath);
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* mesh_path_del - delete a mesh path from the table
|
|
*
|
|
* @addr: dst address (ETH_ALEN length)
|
|
* @sdata: local subif
|
|
*
|
|
* Returns: 0 if successful
|
|
*/
|
|
int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
|
|
{
|
|
int err;
|
|
|
|
/* flush relevant mpp entries first */
|
|
mpp_flush_by_proxy(sdata, addr);
|
|
|
|
err = table_path_del(sdata->u.mesh.mesh_paths, sdata, addr);
|
|
sdata->u.mesh.mesh_paths_generation++;
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* mesh_path_tx_pending - sends pending frames in a mesh path queue
|
|
*
|
|
* @mpath: mesh path to activate
|
|
*
|
|
* Locking: the state_lock of the mpath structure must NOT be held when calling
|
|
* this function.
|
|
*/
|
|
void mesh_path_tx_pending(struct mesh_path *mpath)
|
|
{
|
|
if (mpath->flags & MESH_PATH_ACTIVE)
|
|
ieee80211_add_pending_skbs(mpath->sdata->local,
|
|
&mpath->frame_queue);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_send_to_gates - sends pending frames to all known mesh gates
|
|
*
|
|
* @mpath: mesh path whose queue will be emptied
|
|
*
|
|
* If there is only one gate, the frames are transferred from the failed mpath
|
|
* queue to that gate's queue. If there are more than one gates, the frames
|
|
* are copied from each gate to the next. After frames are copied, the
|
|
* mpath queues are emptied onto the transmission queue.
|
|
*/
|
|
int mesh_path_send_to_gates(struct mesh_path *mpath)
|
|
{
|
|
struct ieee80211_sub_if_data *sdata = mpath->sdata;
|
|
struct mesh_table *tbl;
|
|
struct mesh_path *from_mpath = mpath;
|
|
struct mesh_path *gate;
|
|
bool copy = false;
|
|
|
|
tbl = sdata->u.mesh.mesh_paths;
|
|
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
|
|
if (gate->flags & MESH_PATH_ACTIVE) {
|
|
mpath_dbg(sdata, "Forwarding to %pM\n", gate->dst);
|
|
mesh_path_move_to_queue(gate, from_mpath, copy);
|
|
from_mpath = gate;
|
|
copy = true;
|
|
} else {
|
|
mpath_dbg(sdata,
|
|
"Not forwarding to %pM (flags %#x)\n",
|
|
gate->dst, gate->flags);
|
|
}
|
|
}
|
|
|
|
hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
|
|
mpath_dbg(sdata, "Sending to %pM\n", gate->dst);
|
|
mesh_path_tx_pending(gate);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
|
|
}
|
|
|
|
/**
|
|
* mesh_path_discard_frame - discard a frame whose path could not be resolved
|
|
*
|
|
* @skb: frame to discard
|
|
* @sdata: network subif the frame was to be sent through
|
|
*
|
|
* Locking: the function must me called within a rcu_read_lock region
|
|
*/
|
|
void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
|
|
struct sk_buff *skb)
|
|
{
|
|
kfree_skb(skb);
|
|
sdata->u.mesh.mshstats.dropped_frames_no_route++;
|
|
}
|
|
|
|
/**
|
|
* mesh_path_flush_pending - free the pending queue of a mesh path
|
|
*
|
|
* @mpath: mesh path whose queue has to be freed
|
|
*
|
|
* Locking: the function must me called within a rcu_read_lock region
|
|
*/
|
|
void mesh_path_flush_pending(struct mesh_path *mpath)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL)
|
|
mesh_path_discard_frame(mpath->sdata, skb);
|
|
}
|
|
|
|
/**
|
|
* mesh_path_fix_nexthop - force a specific next hop for a mesh path
|
|
*
|
|
* @mpath: the mesh path to modify
|
|
* @next_hop: the next hop to force
|
|
*
|
|
* Locking: this function must be called holding mpath->state_lock
|
|
*/
|
|
void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
|
|
{
|
|
spin_lock_bh(&mpath->state_lock);
|
|
mesh_path_assign_nexthop(mpath, next_hop);
|
|
mpath->sn = 0xffff;
|
|
mpath->metric = 0;
|
|
mpath->hop_count = 0;
|
|
mpath->exp_time = 0;
|
|
mpath->flags = MESH_PATH_FIXED | MESH_PATH_SN_VALID;
|
|
mesh_path_activate(mpath);
|
|
spin_unlock_bh(&mpath->state_lock);
|
|
ewma_mesh_fail_avg_init(&next_hop->mesh->fail_avg);
|
|
/* init it at a low value - 0 start is tricky */
|
|
ewma_mesh_fail_avg_add(&next_hop->mesh->fail_avg, 1);
|
|
mesh_path_tx_pending(mpath);
|
|
}
|
|
|
|
int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
struct mesh_table *tbl_path, *tbl_mpp;
|
|
int ret;
|
|
|
|
tbl_path = mesh_table_alloc();
|
|
if (!tbl_path)
|
|
return -ENOMEM;
|
|
|
|
tbl_mpp = mesh_table_alloc();
|
|
if (!tbl_mpp) {
|
|
ret = -ENOMEM;
|
|
goto free_path;
|
|
}
|
|
|
|
rhashtable_init(&tbl_path->rhead, &mesh_rht_params);
|
|
rhashtable_init(&tbl_mpp->rhead, &mesh_rht_params);
|
|
|
|
sdata->u.mesh.mesh_paths = tbl_path;
|
|
sdata->u.mesh.mpp_paths = tbl_mpp;
|
|
|
|
return 0;
|
|
|
|
free_path:
|
|
mesh_table_free(tbl_path);
|
|
return ret;
|
|
}
|
|
|
|
static
|
|
void mesh_path_tbl_expire(struct ieee80211_sub_if_data *sdata,
|
|
struct mesh_table *tbl)
|
|
{
|
|
struct mesh_path *mpath;
|
|
struct rhashtable_iter iter;
|
|
int ret;
|
|
|
|
ret = rhashtable_walk_init(&tbl->rhead, &iter, GFP_KERNEL);
|
|
if (ret)
|
|
return;
|
|
|
|
rhashtable_walk_start(&iter);
|
|
|
|
while ((mpath = rhashtable_walk_next(&iter))) {
|
|
if (IS_ERR(mpath) && PTR_ERR(mpath) == -EAGAIN)
|
|
continue;
|
|
if (IS_ERR(mpath))
|
|
break;
|
|
if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
|
|
(!(mpath->flags & MESH_PATH_FIXED)) &&
|
|
time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
|
|
__mesh_path_del(tbl, mpath);
|
|
}
|
|
|
|
rhashtable_walk_stop(&iter);
|
|
rhashtable_walk_exit(&iter);
|
|
}
|
|
|
|
void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
mesh_path_tbl_expire(sdata, sdata->u.mesh.mesh_paths);
|
|
mesh_path_tbl_expire(sdata, sdata->u.mesh.mpp_paths);
|
|
}
|
|
|
|
void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata)
|
|
{
|
|
mesh_table_free(sdata->u.mesh.mesh_paths);
|
|
mesh_table_free(sdata->u.mesh.mpp_paths);
|
|
}
|