Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 144ad2a6 authored by Eric Dumazet's avatar Eric Dumazet Committed by Patrick McHardy
Browse files

netfilter: ip6_queue: rwlock to spinlock conversion 



Converts queue_lock rwlock to a spinlock.

(readlocked part can be changed by reads of integer values)

One atomic operation instead of four per ipq_enqueue_packet() call.

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
parent 5756d346

net/ipv6/netfilter/ip6_queue.c

+25 −32
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ typedef int (*ipq_cmpfn)(struct nf_queue_entry *, unsigned long); 


static unsigned char copy_mode __read_mostly = IPQ_COPY_NONE;

static unsigned int queue_maxlen __read_mostly = IPQ_QMAX_DEFAULT;

static DEFINE_RWLOCK(queue_lock);

static DEFINE_SPINLOCK(queue_lock);

static int peer_pid __read_mostly;

static unsigned int copy_range __read_mostly;

static unsigned int queue_total;
@@ -73,10 +73,10 @@ __ipq_set_mode(unsigned char mode, unsigned int range) 
		break;



	case IPQ_COPY_PACKET:

		copy_mode = mode;

		if (range > 0xFFFF)

			range = 0xFFFF;

		copy_range = range;

		if (copy_range > 0xFFFF)

			copy_range = 0xFFFF;

		copy_mode = mode;

		break;



	default:
@@ -102,7 +102,7 @@ ipq_find_dequeue_entry(unsigned long id) 
{

	struct nf_queue_entry *entry = NULL, *i;



	write_lock_bh(&queue_lock);

	spin_lock_bh(&queue_lock);



	list_for_each_entry(i, &queue_list, list) {

		if ((unsigned long)i == id) {
@@ -116,7 +116,7 @@ ipq_find_dequeue_entry(unsigned long id) 
		queue_total--;

	}



	write_unlock_bh(&queue_lock);

	spin_unlock_bh(&queue_lock);

	return entry;

}
@@ -137,9 +137,9 @@ __ipq_flush(ipq_cmpfn cmpfn, unsigned long data) 
static void

ipq_flush(ipq_cmpfn cmpfn, unsigned long data)

{

	write_lock_bh(&queue_lock);

	spin_lock_bh(&queue_lock);

	__ipq_flush(cmpfn, data);

	write_unlock_bh(&queue_lock);

	spin_unlock_bh(&queue_lock);

}



static struct sk_buff *
@@ -153,9 +153,7 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp) 
	struct nlmsghdr *nlh;

	struct timeval tv;



	read_lock_bh(&queue_lock);



	switch (copy_mode) {

	switch (ACCESS_ONCE(copy_mode)) {

	case IPQ_COPY_META:

	case IPQ_COPY_NONE:

		size = NLMSG_SPACE(sizeof(*pmsg));
@@ -163,26 +161,21 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp) 


	case IPQ_COPY_PACKET:

		if (entry->skb->ip_summed == CHECKSUM_PARTIAL &&

		    (*errp = skb_checksum_help(entry->skb))) {

			read_unlock_bh(&queue_lock);

		    (*errp = skb_checksum_help(entry->skb)))

			return NULL;

		}

		if (copy_range == 0 || copy_range > entry->skb->len)



		data_len = ACCESS_ONCE(copy_range);

		if (data_len == 0 || data_len > entry->skb->len)

			data_len = entry->skb->len;

		else

			data_len = copy_range;



		size = NLMSG_SPACE(sizeof(*pmsg) + data_len);

		break;



	default:

		*errp = -EINVAL;

		read_unlock_bh(&queue_lock);

		return NULL;

	}



	read_unlock_bh(&queue_lock);



	skb = alloc_skb(size, GFP_ATOMIC);

	if (!skb)

		goto nlmsg_failure;
@@ -242,7 +235,7 @@ ipq_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) 
	if (nskb == NULL)

		return status;



	write_lock_bh(&queue_lock);

	spin_lock_bh(&queue_lock);



	if (!peer_pid)

		goto err_out_free_nskb;
@@ -266,14 +259,14 @@ ipq_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) 


	__ipq_enqueue_entry(entry);



	write_unlock_bh(&queue_lock);

	spin_unlock_bh(&queue_lock);

	return status;



err_out_free_nskb:

	kfree_skb(nskb);



err_out_unlock:

	write_unlock_bh(&queue_lock);

	spin_unlock_bh(&queue_lock);

	return status;

}
@@ -342,9 +335,9 @@ ipq_set_mode(unsigned char mode, unsigned int range) 
{

	int status;



	write_lock_bh(&queue_lock);

	spin_lock_bh(&queue_lock);

	status = __ipq_set_mode(mode, range);

	write_unlock_bh(&queue_lock);

	spin_unlock_bh(&queue_lock);

	return status;

}
@@ -441,11 +434,11 @@ __ipq_rcv_skb(struct sk_buff *skb) 
	if (security_netlink_recv(skb, CAP_NET_ADMIN))

		RCV_SKB_FAIL(-EPERM);



	write_lock_bh(&queue_lock);

	spin_lock_bh(&queue_lock);



	if (peer_pid) {

		if (peer_pid != pid) {

			write_unlock_bh(&queue_lock);

			spin_unlock_bh(&queue_lock);

			RCV_SKB_FAIL(-EBUSY);

		}

	} else {
@@ -453,7 +446,7 @@ __ipq_rcv_skb(struct sk_buff *skb) 
		peer_pid = pid;

	}



	write_unlock_bh(&queue_lock);

	spin_unlock_bh(&queue_lock);



	status = ipq_receive_peer(NLMSG_DATA(nlh), type,

				  nlmsglen - NLMSG_LENGTH(0));
@@ -498,10 +491,10 @@ ipq_rcv_nl_event(struct notifier_block *this, 
	struct netlink_notify *n = ptr;



	if (event == NETLINK_URELEASE && n->protocol == NETLINK_IP6_FW) {

		write_lock_bh(&queue_lock);

		spin_lock_bh(&queue_lock);

		if ((net_eq(n->net, &init_net)) && (n->pid == peer_pid))

			__ipq_reset();

		write_unlock_bh(&queue_lock);

		spin_unlock_bh(&queue_lock);

	}

	return NOTIFY_DONE;

}
@@ -528,7 +521,7 @@ static ctl_table ipq_table[] = { 
#ifdef CONFIG_PROC_FS

static int ip6_queue_show(struct seq_file *m, void *v)

{

	read_lock_bh(&queue_lock);

	spin_lock_bh(&queue_lock);



	seq_printf(m,

		      "Peer PID          : %d\n"
@@ -546,7 +539,7 @@ static int ip6_queue_show(struct seq_file *m, void *v) 
		      queue_dropped,

		      queue_user_dropped);



	read_unlock_bh(&queue_lock);

	spin_unlock_bh(&queue_lock);

	return 0;

}