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authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 09:41:05 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 09:41:05 -0800
commitb0f85fa11aefc4f3e03306b4cd47f113bd57dcba (patch)
tree1333d36d99fde3f97210795941fc246f0ad08a75 /net/ipv4/tcp_fastopen.c
parentccc9d4a6d640cbde05d519edeb727881646cf71b (diff)
parentf32bfb9a8ca083f8d148ea90ae5ba66f4831836e (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: Changes of note: 1) Allow to schedule ICMP packets in IPVS, from Alex Gartrell. 2) Provide FIB table ID in ipv4 route dumps just as ipv6 does, from David Ahern. 3) Allow the user to ask for the statistics to be filtered out of ipv4/ipv6 address netlink dumps. From Sowmini Varadhan. 4) More work to pass the network namespace context around deep into various packet path APIs, starting with the netfilter hooks. From Eric W Biederman. 5) Add layer 2 TX/RX checksum offloading to qeth driver, from Thomas Richter. 6) Use usec resolution for SYN/ACK RTTs in TCP, from Yuchung Cheng. 7) Support Very High Throughput in wireless MESH code, from Bob Copeland. 8) Allow setting the ageing_time in switchdev/rocker. From Scott Feldman. 9) Properly autoload L2TP type modules, from Stephen Hemminger. 10) Fix and enable offload features by default in 8139cp driver, from David Woodhouse. 11) Support both ipv4 and ipv6 sockets in a single vxlan device, from Jiri Benc. 12) Fix CWND limiting of thin streams in TCP, from Bendik Rønning Opstad. 13) Fix IPSEC flowcache overflows on large systems, from Steffen Klassert. 14) Convert bridging to track VLANs using rhashtable entries rather than a bitmap. From Nikolay Aleksandrov. 15) Make TCP listener handling completely lockless, this is a major accomplishment. Incoming request sockets now live in the established hash table just like any other socket too. From Eric Dumazet. 15) Provide more bridging attributes to netlink, from Nikolay Aleksandrov. 16) Use hash based algorithm for ipv4 multipath routing, this was very long overdue. From Peter Nørlund. 17) Several y2038 cures, mostly avoiding timespec. From Arnd Bergmann. 18) Allow non-root execution of EBPF programs, from Alexei Starovoitov. 19) Support SO_INCOMING_CPU as setsockopt, from Eric Dumazet. This influences the port binding selection logic used by SO_REUSEPORT. 20) Add ipv6 support to VRF, from David Ahern. 21) Add support for Mellanox Spectrum switch ASIC, from Jiri Pirko. 22) Add rtl8xxxu Realtek wireless driver, from Jes Sorensen. 23) Implement RACK loss recovery in TCP, from Yuchung Cheng. 24) Support multipath routes in MPLS, from Roopa Prabhu. 25) Fix POLLOUT notification for listening sockets in AF_UNIX, from Eric Dumazet. 26) Add new QED Qlogic river, from Yuval Mintz, Manish Chopra, and Sudarsana Kalluru. 27) Don't fetch timestamps on AF_UNIX sockets, from Hannes Frederic Sowa. 28) Support ipv6 geneve tunnels, from John W Linville. 29) Add flood control support to switchdev layer, from Ido Schimmel. 30) Fix CHECKSUM_PARTIAL handling of potentially fragmented frames, from Hannes Frederic Sowa. 31) Support persistent maps and progs in bpf, from Daniel Borkmann. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1790 commits) sh_eth: use DMA barriers switchdev: respect SKIP_EOPNOTSUPP flag in case there is no recursion net: sched: kill dead code in sch_choke.c irda: Delete an unnecessary check before the function call "irlmp_unregister_service" net: dsa: mv88e6xxx: include DSA ports in VLANs net: dsa: mv88e6xxx: disable SA learning for DSA and CPU ports net/core: fix for_each_netdev_feature vlan: Invoke driver vlan hooks only if device is present arcnet/com20020: add LEDS_CLASS dependency bpf, verifier: annotate verbose printer with __printf dp83640: Only wait for timestamps for packets with timestamping enabled. ptp: Change ptp_class to a proper bitmask dp83640: Prune rx timestamp list before reading from it dp83640: Delay scheduled work. dp83640: Include hash in timestamp/packet matching ipv6: fix tunnel error handling net/mlx5e: Fix LSO vlan insertion net/mlx5e: Re-eanble client vlan TX acceleration net/mlx5e: Return error in case mlx5e_set_features() fails net/mlx5e: Don't allow more than max supported channels ...
Diffstat (limited to 'net/ipv4/tcp_fastopen.c')
-rw-r--r--net/ipv4/tcp_fastopen.c75
1 files changed, 34 insertions, 41 deletions
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index f9c0fb84e435..55be6ac70cff 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -124,27 +124,29 @@ static bool tcp_fastopen_cookie_gen(struct request_sock *req,
return false;
}
-static bool tcp_fastopen_create_child(struct sock *sk,
- struct sk_buff *skb,
- struct dst_entry *dst,
- struct request_sock *req)
+static struct sock *tcp_fastopen_create_child(struct sock *sk,
+ struct sk_buff *skb,
+ struct dst_entry *dst,
+ struct request_sock *req)
{
struct tcp_sock *tp;
struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue;
struct sock *child;
u32 end_seq;
+ bool own_req;
req->num_retrans = 0;
req->num_timeout = 0;
req->sk = NULL;
- child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
+ child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL,
+ NULL, &own_req);
if (!child)
- return false;
+ return NULL;
- spin_lock(&queue->fastopenq->lock);
- queue->fastopenq->qlen++;
- spin_unlock(&queue->fastopenq->lock);
+ spin_lock(&queue->fastopenq.lock);
+ queue->fastopenq.qlen++;
+ spin_unlock(&queue->fastopenq.lock);
/* Initialize the child socket. Have to fix some values to take
* into account the child is a Fast Open socket and is created
@@ -161,15 +163,13 @@ static bool tcp_fastopen_create_child(struct sock *sk,
tp->snd_wnd = ntohs(tcp_hdr(skb)->window);
/* Activate the retrans timer so that SYNACK can be retransmitted.
- * The request socket is not added to the SYN table of the parent
+ * The request socket is not added to the ehash
* because it's been added to the accept queue directly.
*/
inet_csk_reset_xmit_timer(child, ICSK_TIME_RETRANS,
TCP_TIMEOUT_INIT, TCP_RTO_MAX);
- atomic_set(&req->rsk_refcnt, 1);
- /* Add the child socket directly into the accept queue */
- inet_csk_reqsk_queue_add(sk, req, child);
+ atomic_set(&req->rsk_refcnt, 2);
/* Now finish processing the fastopen child socket. */
inet_csk(child)->icsk_af_ops->rebuild_header(child);
@@ -178,12 +178,10 @@ static bool tcp_fastopen_create_child(struct sock *sk,
tcp_init_metrics(child);
tcp_init_buffer_space(child);
- /* Queue the data carried in the SYN packet. We need to first
- * bump skb's refcnt because the caller will attempt to free it.
- * Note that IPv6 might also have used skb_get() trick
- * in tcp_v6_conn_request() to keep this SYN around (treq->pktopts)
- * So we need to eventually get a clone of the packet,
- * before inserting it in sk_receive_queue.
+ /* Queue the data carried in the SYN packet.
+ * We used to play tricky games with skb_get().
+ * With lockless listener, it is a dead end.
+ * Do not think about it.
*
* XXX (TFO) - we honor a zero-payload TFO request for now,
* (any reason not to?) but no need to queue the skb since
@@ -191,12 +189,7 @@ static bool tcp_fastopen_create_child(struct sock *sk,
*/
end_seq = TCP_SKB_CB(skb)->end_seq;
if (end_seq != TCP_SKB_CB(skb)->seq + 1) {
- struct sk_buff *skb2;
-
- if (unlikely(skb_shared(skb)))
- skb2 = skb_clone(skb, GFP_ATOMIC);
- else
- skb2 = skb_get(skb);
+ struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
if (likely(skb2)) {
skb_dst_drop(skb2);
@@ -214,11 +207,10 @@ static bool tcp_fastopen_create_child(struct sock *sk,
}
}
tcp_rsk(req)->rcv_nxt = tp->rcv_nxt = end_seq;
- sk->sk_data_ready(sk);
- bh_unlock_sock(child);
- sock_put(child);
- WARN_ON(!req->sk);
- return true;
+ /* tcp_conn_request() is sending the SYNACK,
+ * and queues the child into listener accept queue.
+ */
+ return child;
}
static bool tcp_fastopen_queue_check(struct sock *sk)
@@ -235,8 +227,8 @@ static bool tcp_fastopen_queue_check(struct sock *sk)
* between qlen overflow causing Fast Open to be disabled
* temporarily vs a server not supporting Fast Open at all.
*/
- fastopenq = inet_csk(sk)->icsk_accept_queue.fastopenq;
- if (!fastopenq || fastopenq->max_qlen == 0)
+ fastopenq = &inet_csk(sk)->icsk_accept_queue.fastopenq;
+ if (fastopenq->max_qlen == 0)
return false;
if (fastopenq->qlen >= fastopenq->max_qlen) {
@@ -261,13 +253,14 @@ static bool tcp_fastopen_queue_check(struct sock *sk)
* may be updated and return the client in the SYN-ACK later. E.g., Fast Open
* cookie request (foc->len == 0).
*/
-bool tcp_try_fastopen(struct sock *sk, struct sk_buff *skb,
- struct request_sock *req,
- struct tcp_fastopen_cookie *foc,
- struct dst_entry *dst)
+struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb,
+ struct request_sock *req,
+ struct tcp_fastopen_cookie *foc,
+ struct dst_entry *dst)
{
struct tcp_fastopen_cookie valid_foc = { .len = -1 };
bool syn_data = TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1;
+ struct sock *child;
if (foc->len == 0) /* Client requests a cookie */
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPFASTOPENCOOKIEREQD);
@@ -276,7 +269,7 @@ bool tcp_try_fastopen(struct sock *sk, struct sk_buff *skb,
(syn_data || foc->len >= 0) &&
tcp_fastopen_queue_check(sk))) {
foc->len = -1;
- return false;
+ return NULL;
}
if (syn_data && (sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_REQD))
@@ -296,11 +289,12 @@ bool tcp_try_fastopen(struct sock *sk, struct sk_buff *skb,
* data in SYN_RECV state.
*/
fastopen:
- if (tcp_fastopen_create_child(sk, skb, dst, req)) {
+ child = tcp_fastopen_create_child(sk, skb, dst, req);
+ if (child) {
foc->len = -1;
NET_INC_STATS_BH(sock_net(sk),
LINUX_MIB_TCPFASTOPENPASSIVE);
- return true;
+ return child;
}
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVEFAIL);
} else if (foc->len > 0) /* Client presents an invalid cookie */
@@ -308,6 +302,5 @@ fastopen:
valid_foc.exp = foc->exp;
*foc = valid_foc;
- return false;
+ return NULL;
}
-EXPORT_SYMBOL(tcp_try_fastopen);