[B.A.T.M.A.N.] [PATCH] batman-adv: Prepare vis packets directly inside a skb

The vis information structure is used in a way that it can be transfered directly as packet. It still had to be copied into an skb because of an extra buffer used for the actual preparation of the data. This is unnecessary and can be replaced by a simple clone instead of an full copy before each send.

This makes also the send_raw_packet function obsolete.

Signed-off-by: Sven Eckelmann sven.eckelmann@gmx.de --- batman-adv/send.c | 17 ----- batman-adv/send.h | 2 - batman-adv/vis.c | 206 ++++++++++++++++++++++++++++++++++------------------- batman-adv/vis.h | 2 +- 4 files changed, 133 insertions(+), 94 deletions(-)

diff --git a/batman-adv/send.c b/batman-adv/send.c index 09a87c6..19b1962 100644 --- a/batman-adv/send.c +++ b/batman-adv/send.c @@ -105,23 +105,6 @@ send_skb_err: return NET_XMIT_DROP; }

-/* sends a raw packet. */ -void send_raw_packet(unsigned char *pack_buff, int pack_buff_len, - struct batman_if *batman_if, uint8_t *dst_addr) -{ - struct sk_buff *skb; - char *data; - - skb = dev_alloc_skb(pack_buff_len + sizeof(struct ethhdr)); - if (!skb) - return; - data = skb_put(skb, pack_buff_len + sizeof(struct ethhdr)); - memcpy(data + sizeof(struct ethhdr), pack_buff, pack_buff_len); - /* pull back to the batman "network header" */ - skb_pull(skb, sizeof(struct ethhdr)); - send_skb_packet(skb, batman_if, dst_addr); -} - /* Send a packet to a given interface */ static void send_packet_to_if(struct forw_packet *forw_packet, struct batman_if *batman_if) diff --git a/batman-adv/send.h b/batman-adv/send.h index b64c627..0cfe027 100644 --- a/batman-adv/send.h +++ b/batman-adv/send.h @@ -27,8 +27,6 @@ int send_skb_packet(struct sk_buff *skb, struct batman_if *batman_if, uint8_t *dst_addr); -void send_raw_packet(unsigned char *pack_buff, int pack_buff_len, - struct batman_if *batman_if, uint8_t *dst_addr); void schedule_own_packet(struct batman_if *batman_if); void schedule_forward_packet(struct orig_node *orig_node, struct ethhdr *ethhdr, diff --git a/batman-adv/vis.c b/batman-adv/vis.c index 5c825b5..c225e27 100644 --- a/batman-adv/vis.c +++ b/batman-adv/vis.c @@ -44,6 +44,8 @@ _dummy > smallest_signed_int(_dummy); }) #define seq_after(x, y) seq_before(y, x)

+#define MAX_VIS_PACKET_SIZE 1000 + static struct hashtable_t *vis_hash; static DEFINE_SPINLOCK(vis_hash_lock); static DEFINE_SPINLOCK(recv_list_lock); @@ -66,6 +68,7 @@ static void free_info(struct kref *ref) kfree(entry); } spin_unlock_irqrestore(&recv_list_lock, flags); + kfree_skb(info->skb_packet); kfree(info); }

@@ -73,9 +76,12 @@ static void free_info(struct kref *ref) static int vis_info_cmp(void *data1, void *data2) { struct vis_info *d1, *d2; + struct vis_packet *p1, *p2; d1 = data1; d2 = data2; - return compare_orig(d1->packet.vis_orig, d2->packet.vis_orig); + p1 = (struct vis_packet *)d1->skb_packet->data; + p2 = (struct vis_packet *)d2->skb_packet->data; + return compare_orig(p1->vis_orig, p2->vis_orig); }

/* hash function to choose an entry in a hash table of given size */ @@ -83,11 +89,13 @@ static int vis_info_cmp(void *data1, void *data2) static int vis_info_choose(void *data, int size) { struct vis_info *vis_info = data; + struct vis_packet *packet; unsigned char *key; uint32_t hash = 0; size_t i;

- key = vis_info->packet.vis_orig; + packet = (struct vis_packet *)vis_info->skb_packet->data; + key = packet->vis_orig; for (i = 0; i < ETH_ALEN; i++) { hash += key[i]; hash += (hash << 10); @@ -180,6 +188,7 @@ int vis_seq_print_text(struct seq_file *seq, void *offset) HASHIT(hashit); HASHIT(hashit_count); struct vis_info *info; + struct vis_packet *packet; struct vis_info_entry *entries; struct net_device *net_dev = (struct net_device *)seq->private; struct bat_priv *bat_priv = netdev_priv(net_dev); @@ -202,22 +211,22 @@ int vis_seq_print_text(struct seq_file *seq, void *offset) spin_lock_irqsave(&vis_hash_lock, flags); while (hash_iterate(vis_hash, &hashit_count)) { info = hashit_count.bucket->data; + packet = (struct vis_packet *)info->skb_packet->data; entries = (struct vis_info_entry *) - ((char *)info + sizeof(struct vis_info)); + ((char *)packet + sizeof(struct vis_packet));

- for (i = 0; i < info->packet.entries; i++) { + for (i = 0; i < packet->entries; i++) { if (entries[i].quality == 0) continue; vis_data_insert_interface(entries[i].src, &vis_if_list, - compare_orig(entries[i].src, - info->packet.vis_orig)); + compare_orig(entries[i].src, packet->vis_orig)); }

hlist_for_each_entry(entry, pos, &vis_if_list, list) { - buf_size += 18 + 26 * info->packet.entries; + buf_size += 18 + 26 * packet->entries;

/* add primary/secondary records */ - if (compare_orig(entry->addr, info->packet.vis_orig)) + if (compare_orig(entry->addr, packet->vis_orig)) buf_size += vis_data_count_prim_sec(&vis_if_list);

@@ -240,15 +249,15 @@ int vis_seq_print_text(struct seq_file *seq, void *offset)

while (hash_iterate(vis_hash, &hashit)) { info = hashit.bucket->data; + packet = (struct vis_packet *)info->skb_packet->data; entries = (struct vis_info_entry *) - ((char *)info + sizeof(struct vis_info)); + ((char *)packet + sizeof(struct vis_packet));

- for (i = 0; i < info->packet.entries; i++) { + for (i = 0; i < packet->entries; i++) { if (entries[i].quality == 0) continue; vis_data_insert_interface(entries[i].src, &vis_if_list, - compare_orig(entries[i].src, - info->packet.vis_orig)); + compare_orig(entries[i].src, packet->vis_orig)); }

hlist_for_each_entry(entry, pos, &vis_if_list, list) { @@ -256,14 +265,14 @@ int vis_seq_print_text(struct seq_file *seq, void *offset) buff_pos += sprintf(buff + buff_pos, "%s,", tmp_addr_str);

- for (i = 0; i < info->packet.entries; i++) + for (i = 0; i < packet->entries; i++) buff_pos += vis_data_read_entry(buff + buff_pos, &entries[i], entry->addr, entry->primary);

/* add primary/secondary records */ - if (compare_orig(entry->addr, info->packet.vis_orig)) + if (compare_orig(entry->addr, packet->vis_orig)) buff_pos += vis_data_read_prim_sec(buff + buff_pos, &vis_if_list); @@ -346,7 +355,9 @@ static struct vis_info *add_packet(struct vis_packet *vis_packet, int make_broadcast) { struct vis_info *info, *old_info; + struct vis_packet *search_packet, *old_packet; struct vis_info search_elem; + struct vis_packet *packet;

*is_new = 0; /* sanity check */ @@ -354,13 +365,21 @@ static struct vis_info *add_packet(struct vis_packet *vis_packet, return NULL;

/* see if the packet is already in vis_hash */ - memcpy(search_elem.packet.vis_orig, vis_packet->vis_orig, ETH_ALEN); + search_elem.skb_packet = dev_alloc_skb(sizeof(struct vis_packet)); + if (!search_elem.skb_packet) + return NULL; + search_packet = (struct vis_packet *)skb_put(search_elem.skb_packet, + sizeof(struct vis_packet)); + + memcpy(search_packet->vis_orig, vis_packet->vis_orig, ETH_ALEN); old_info = hash_find(vis_hash, &search_elem); + kfree_skb(search_elem.skb_packet);

if (old_info != NULL) { + old_packet = (struct vis_packet *)old_info->skb_packet->data; if (!seq_after(ntohl(vis_packet->seqno), - ntohl(old_info->packet.seqno))) { - if (old_info->packet.seqno == vis_packet->seqno) { + ntohl(old_packet->seqno))) { + if (old_packet->seqno == vis_packet->seqno) { recv_list_add(&old_info->recv_list, vis_packet->sender_orig); return old_info; @@ -375,30 +394,39 @@ static struct vis_info *add_packet(struct vis_packet *vis_packet, kref_put(&old_info->refcount, free_info); }

- info = kmalloc(sizeof(struct vis_info) + vis_info_len, GFP_ATOMIC); + info = kmalloc(sizeof(struct vis_info), GFP_ATOMIC); if (info == NULL) return NULL;

+ info->skb_packet = dev_alloc_skb(sizeof(struct vis_packet) + + vis_info_len + sizeof(struct ethhdr)); + if (!info->skb_packet) { + kfree(info); + return NULL; + } + skb_reserve(info->skb_packet, sizeof(struct ethhdr)); + packet = (struct vis_packet *)skb_put(info->skb_packet, + sizeof(struct vis_packet) + + vis_info_len); + kref_init(&info->refcount); INIT_LIST_HEAD(&info->send_list); INIT_LIST_HEAD(&info->recv_list); info->first_seen = jiffies; - memcpy(&info->packet, vis_packet, - sizeof(struct vis_packet) + vis_info_len); + memcpy(packet, vis_packet, sizeof(struct vis_packet) + vis_info_len);

/* initialize and add new packet. */ *is_new = 1;

/* Make it a broadcast packet, if required */ if (make_broadcast) - memcpy(info->packet.target_orig, broadcast_addr, ETH_ALEN); + memcpy(packet->target_orig, broadcast_addr, ETH_ALEN);

/* repair if entries is longer than packet. */ - if (info->packet.entries * sizeof(struct vis_info_entry) > vis_info_len) - info->packet.entries = vis_info_len / - sizeof(struct vis_info_entry); + if (packet->entries * sizeof(struct vis_info_entry) > vis_info_len) + packet->entries = vis_info_len / sizeof(struct vis_info_entry);

- recv_list_add(&info->recv_list, info->packet.sender_orig); + recv_list_add(&info->recv_list, packet->sender_orig);

/* try to add it */ if (hash_add(vis_hash, info) < 0) { @@ -441,6 +469,7 @@ void receive_client_update_packet(struct bat_priv *bat_priv, int vis_info_len) { struct vis_info *info; + struct vis_packet *packet; int is_new; unsigned long flags; int vis_server = atomic_read(&bat_priv->vis_mode); @@ -457,20 +486,23 @@ void receive_client_update_packet(struct bat_priv *bat_priv,

spin_lock_irqsave(&vis_hash_lock, flags); info = add_packet(vis_packet, vis_info_len, &is_new, are_target); + if (info == NULL) goto end; /* note that outdated packets will be dropped at this point. */

+ packet = (struct vis_packet *)info->skb_packet->data;

/* send only if we're the target server or ... */ if (are_target && is_new) { - info->packet.vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */ + packet->vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */ send_list_add(info);

/* ... we're not the recipient (and thus need to forward). */ - } else if (!is_my_mac(info->packet.target_orig)) { + } else if (!is_my_mac(packet->target_orig)) { send_list_add(info); } + end: spin_unlock_irqrestore(&vis_hash_lock, flags); } @@ -483,8 +515,11 @@ static int find_best_vis_server(struct vis_info *info) { HASHIT(hashit); struct orig_node *orig_node; + struct vis_packet *packet; int best_tq = -1;

+ packet = (struct vis_packet *)info->skb_packet->data; + while (hash_iterate(orig_hash, &hashit)) { orig_node = hashit.bucket->data; if ((orig_node != NULL) && @@ -492,8 +527,7 @@ static int find_best_vis_server(struct vis_info *info) (orig_node->flags & VIS_SERVER) && (orig_node->router->tq_avg > best_tq)) { best_tq = orig_node->router->tq_avg; - memcpy(info->packet.target_orig, orig_node->orig, - ETH_ALEN); + memcpy(packet->target_orig, orig_node->orig, ETH_ALEN); } } return best_tq; @@ -502,8 +536,11 @@ static int find_best_vis_server(struct vis_info *info) /* Return true if the vis packet is full. */ static bool vis_packet_full(struct vis_info *info) { - if (info->packet.entries + 1 > - (1000 - sizeof(struct vis_info)) / sizeof(struct vis_info_entry)) + struct vis_packet *packet; + packet = (struct vis_packet *)info->skb_packet->data; + + if (MAX_VIS_PACKET_SIZE / sizeof(struct vis_info_entry) + < packet->entries + 1) return true; return false; } @@ -516,21 +553,23 @@ static int generate_vis_packet(struct bat_priv *bat_priv) HASHIT(hashit_global); struct orig_node *orig_node; struct vis_info *info = (struct vis_info *)my_vis_info; - struct vis_info_entry *entry, *entry_array; + struct vis_packet *packet = (struct vis_packet *)info->skb_packet->data; + struct vis_info_entry *entry; struct hna_local_entry *hna_local_entry; int best_tq = -1; unsigned long flags;

info->first_seen = jiffies; - info->packet.vis_type = atomic_read(&bat_priv->vis_mode); + packet->vis_type = atomic_read(&bat_priv->vis_mode);

spin_lock_irqsave(&orig_hash_lock, flags); - memcpy(info->packet.target_orig, broadcast_addr, ETH_ALEN); - info->packet.ttl = TTL; - info->packet.seqno = htonl(ntohl(info->packet.seqno) + 1); - info->packet.entries = 0; + memcpy(packet->target_orig, broadcast_addr, ETH_ALEN); + packet->ttl = TTL; + packet->seqno = htonl(ntohl(packet->seqno) + 1); + packet->entries = 0; + skb_trim(info->skb_packet, sizeof(struct vis_packet));

- if (info->packet.vis_type == VIS_TYPE_CLIENT_UPDATE) { + if (packet->vis_type == VIS_TYPE_CLIENT_UPDATE) { best_tq = find_best_vis_server(info); if (best_tq < 0) { spin_unlock_irqrestore(&orig_hash_lock, flags); @@ -538,9 +577,6 @@ static int generate_vis_packet(struct bat_priv *bat_priv) } }

- entry_array = (struct vis_info_entry *) - ((char *)info + sizeof(struct vis_info)); - while (hash_iterate(orig_hash, &hashit_global)) { orig_node = hashit_global.bucket->data; if (orig_node->router != NULL @@ -551,13 +587,14 @@ static int generate_vis_packet(struct bat_priv *bat_priv) && orig_node->router->tq_avg > 0) {

/* fill one entry into buffer. */ - entry = &entry_array[info->packet.entries]; + entry = (struct vis_info_entry *) + skb_put(info->skb_packet, sizeof(*entry)); memcpy(entry->src, orig_node->router->if_incoming->net_dev->dev_addr, ETH_ALEN); memcpy(entry->dest, orig_node->orig, ETH_ALEN); entry->quality = orig_node->router->tq_avg; - info->packet.entries++; + packet->entries++;

if (vis_packet_full(info)) { spin_unlock_irqrestore(&orig_hash_lock, flags); @@ -571,11 +608,12 @@ static int generate_vis_packet(struct bat_priv *bat_priv) spin_lock_irqsave(&hna_local_hash_lock, flags); while (hash_iterate(hna_local_hash, &hashit_local)) { hna_local_entry = hashit_local.bucket->data; - entry = &entry_array[info->packet.entries]; + entry = (struct vis_info_entry *)skb_put(info->skb_packet, + sizeof(*entry)); memset(entry->src, 0, ETH_ALEN); memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN); entry->quality = 0; /* 0 means HNA */ - info->packet.entries++; + packet->entries++;

if (vis_packet_full(info)) { spin_unlock_irqrestore(&hna_local_hash_lock, flags); @@ -606,15 +644,18 @@ static void purge_vis_packets(void) } }

-static void broadcast_vis_packet(struct vis_info *info, int packet_length) +static void broadcast_vis_packet(struct vis_info *info) { HASHIT(hashit); struct orig_node *orig_node; + struct vis_packet *packet; + struct sk_buff *skb; unsigned long flags; struct batman_if *batman_if; uint8_t dstaddr[ETH_ALEN];

spin_lock_irqsave(&orig_hash_lock, flags); + packet = (struct vis_packet *)info->skb_packet->data;

/* send to all routers in range. */ while (hash_iterate(orig_hash, &hashit)) { @@ -630,31 +671,35 @@ static void broadcast_vis_packet(struct vis_info *info, int packet_length) if (recv_list_is_in(&info->recv_list, orig_node->orig)) continue;

- memcpy(info->packet.target_orig, orig_node->orig, ETH_ALEN); + memcpy(packet->target_orig, orig_node->orig, ETH_ALEN); batman_if = orig_node->router->if_incoming; memcpy(dstaddr, orig_node->router->addr, ETH_ALEN); spin_unlock_irqrestore(&orig_hash_lock, flags);

- send_raw_packet((unsigned char *)&info->packet, - packet_length, batman_if, dstaddr); + skb = skb_clone(info->skb_packet, GFP_ATOMIC); + if (skb) + send_skb_packet(skb, batman_if, dstaddr);

spin_lock_irqsave(&orig_hash_lock, flags);

} spin_unlock_irqrestore(&orig_hash_lock, flags); - memcpy(info->packet.target_orig, broadcast_addr, ETH_ALEN); + memcpy(packet->target_orig, broadcast_addr, ETH_ALEN); }

-static void unicast_vis_packet(struct vis_info *info, int packet_length) +static void unicast_vis_packet(struct vis_info *info) { struct orig_node *orig_node; + struct sk_buff *skb; + struct vis_packet *packet; unsigned long flags; struct batman_if *batman_if; uint8_t dstaddr[ETH_ALEN];

spin_lock_irqsave(&orig_hash_lock, flags); - orig_node = ((struct orig_node *) - hash_find(orig_hash, info->packet.target_orig)); + packet = (struct vis_packet *)info->skb_packet->data; + orig_node = ((struct orig_node *)hash_find(orig_hash, + packet->target_orig));

if ((!orig_node) || (!orig_node->router)) goto out; @@ -665,8 +710,10 @@ static void unicast_vis_packet(struct vis_info *info, int packet_length) memcpy(dstaddr, orig_node->router->addr, ETH_ALEN); spin_unlock_irqrestore(&orig_hash_lock, flags);

- send_raw_packet((unsigned char *)&info->packet, - packet_length, batman_if, dstaddr); + skb = skb_clone(info->skb_packet, GFP_ATOMIC); + if (skb) + send_skb_packet(skb, batman_if, dstaddr); + return;

out: @@ -676,24 +723,22 @@ out: /* only send one vis packet. called from send_vis_packets() */ static void send_vis_packet(struct vis_info *info) { - int packet_length; + struct vis_packet *packet;

- if (info->packet.ttl < 2) { + packet = (struct vis_packet *)info->skb_packet->data; + if (packet->ttl < 2) { pr_warning("Error - can't send vis packet: ttl exceeded\n"); return; }

- memcpy(info->packet.sender_orig, main_if_addr, ETH_ALEN); - info->packet.ttl--; + memcpy(packet->sender_orig, main_if_addr, ETH_ALEN); + packet->ttl--;

- packet_length = sizeof(struct vis_packet) + - info->packet.entries * sizeof(struct vis_info_entry); - - if (is_bcast(info->packet.target_orig)) - broadcast_vis_packet(info, packet_length); + if (is_bcast(packet->target_orig)) + broadcast_vis_packet(info); else - unicast_vis_packet(info, packet_length); - info->packet.ttl++; /* restore TTL */ + unicast_vis_packet(info); + packet->ttl++; /* restore TTL */ }

/* called from timer; send (and maybe generate) vis packet. */ @@ -733,6 +778,7 @@ static DECLARE_DELAYED_WORK(vis_timer_wq, send_vis_packets); * initialized (e.g. bat0 is initialized, interfaces have been added) */ int vis_init(void) { + struct vis_packet *packet; unsigned long flags; if (vis_hash) return 1; @@ -745,27 +791,36 @@ int vis_init(void) goto err; }

- my_vis_info = kmalloc(1000, GFP_ATOMIC); + my_vis_info = kmalloc(MAX_VIS_PACKET_SIZE, GFP_ATOMIC); if (!my_vis_info) { pr_err("Can't initialize vis packet\n"); goto err; }

+ my_vis_info->skb_packet = dev_alloc_skb(sizeof(struct vis_packet) + + MAX_VIS_PACKET_SIZE + + sizeof(struct ethhdr)); + if (!my_vis_info->skb_packet) + goto free_info; + skb_reserve(my_vis_info->skb_packet, sizeof(struct ethhdr)); + packet = (struct vis_packet *)skb_put(my_vis_info->skb_packet, + sizeof(struct vis_packet)); + /* prefill the vis info */ my_vis_info->first_seen = jiffies - msecs_to_jiffies(VIS_INTERVAL); INIT_LIST_HEAD(&my_vis_info->recv_list); INIT_LIST_HEAD(&my_vis_info->send_list); kref_init(&my_vis_info->refcount); - my_vis_info->packet.version = COMPAT_VERSION; - my_vis_info->packet.packet_type = BAT_VIS; - my_vis_info->packet.ttl = TTL; - my_vis_info->packet.seqno = 0; - my_vis_info->packet.entries = 0; + packet->version = COMPAT_VERSION; + packet->packet_type = BAT_VIS; + packet->ttl = TTL; + packet->seqno = 0; + packet->entries = 0;

INIT_LIST_HEAD(&send_list);

- memcpy(my_vis_info->packet.vis_orig, main_if_addr, ETH_ALEN); - memcpy(my_vis_info->packet.sender_orig, main_if_addr, ETH_ALEN); + memcpy(packet->vis_orig, main_if_addr, ETH_ALEN); + memcpy(packet->sender_orig, main_if_addr, ETH_ALEN);

if (hash_add(vis_hash, my_vis_info) < 0) { pr_err("Can't add own vis packet into hash\n"); @@ -778,6 +833,9 @@ int vis_init(void) start_vis_timer(); return 1;

+free_info: + kfree(my_vis_info); + my_vis_info = NULL; err: spin_unlock_irqrestore(&vis_hash_lock, flags); vis_quit(); diff --git a/batman-adv/vis.h b/batman-adv/vis.h index bb13bf1..19dc325 100644 --- a/batman-adv/vis.h +++ b/batman-adv/vis.h @@ -32,7 +32,7 @@ struct vis_info { struct list_head send_list; struct kref refcount; /* this packet might be part of the vis send queue. */ - struct vis_packet packet; + struct sk_buff *skb_packet; /* vis_info may follow here*/ } __attribute__((packed));