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Diffstat (limited to 'net/ipv4/tcp.c')
-rw-r--r--net/ipv4/tcp.c344
1 files changed, 28 insertions, 316 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index ab450c099aa4..15cbfa94bd8e 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -279,6 +279,7 @@
#include <asm/uaccess.h>
#include <asm/ioctls.h>
+#include <net/ll_poll.h>
int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT;
@@ -436,6 +437,8 @@ unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
struct sock *sk = sock->sk;
const struct tcp_sock *tp = tcp_sk(sk);
+ sock_rps_record_flow(sk);
+
sock_poll_wait(file, sk_sleep(sk), wait);
if (sk->sk_state == TCP_LISTEN)
return inet_csk_listen_poll(sk);
@@ -1551,6 +1554,10 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
struct sk_buff *skb;
u32 urg_hole = 0;
+ if (sk_can_busy_loop(sk) && skb_queue_empty(&sk->sk_receive_queue) &&
+ (sk->sk_state == TCP_ESTABLISHED))
+ sk_busy_loop(sk, nonblock);
+
lock_sock(sk);
err = -ENOTCONN;
@@ -2875,249 +2882,9 @@ int compat_tcp_getsockopt(struct sock *sk, int level, int optname,
EXPORT_SYMBOL(compat_tcp_getsockopt);
#endif
-struct sk_buff *tcp_tso_segment(struct sk_buff *skb,
- netdev_features_t features)
-{
- struct sk_buff *segs = ERR_PTR(-EINVAL);
- struct tcphdr *th;
- unsigned int thlen;
- unsigned int seq;
- __be32 delta;
- unsigned int oldlen;
- unsigned int mss;
- struct sk_buff *gso_skb = skb;
- __sum16 newcheck;
- bool ooo_okay, copy_destructor;
-
- if (!pskb_may_pull(skb, sizeof(*th)))
- goto out;
-
- th = tcp_hdr(skb);
- thlen = th->doff * 4;
- if (thlen < sizeof(*th))
- goto out;
-
- if (!pskb_may_pull(skb, thlen))
- goto out;
-
- oldlen = (u16)~skb->len;
- __skb_pull(skb, thlen);
-
- mss = skb_shinfo(skb)->gso_size;
- if (unlikely(skb->len <= mss))
- goto out;
-
- if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
- /* Packet is from an untrusted source, reset gso_segs. */
- int type = skb_shinfo(skb)->gso_type;
-
- if (unlikely(type &
- ~(SKB_GSO_TCPV4 |
- SKB_GSO_DODGY |
- SKB_GSO_TCP_ECN |
- SKB_GSO_TCPV6 |
- SKB_GSO_GRE |
- SKB_GSO_UDP_TUNNEL |
- 0) ||
- !(type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))))
- goto out;
-
- skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
-
- segs = NULL;
- goto out;
- }
-
- copy_destructor = gso_skb->destructor == tcp_wfree;
- ooo_okay = gso_skb->ooo_okay;
- /* All segments but the first should have ooo_okay cleared */
- skb->ooo_okay = 0;
-
- segs = skb_segment(skb, features);
- if (IS_ERR(segs))
- goto out;
-
- /* Only first segment might have ooo_okay set */
- segs->ooo_okay = ooo_okay;
-
- delta = htonl(oldlen + (thlen + mss));
-
- skb = segs;
- th = tcp_hdr(skb);
- seq = ntohl(th->seq);
-
- newcheck = ~csum_fold((__force __wsum)((__force u32)th->check +
- (__force u32)delta));
-
- do {
- th->fin = th->psh = 0;
- th->check = newcheck;
-
- if (skb->ip_summed != CHECKSUM_PARTIAL)
- th->check =
- csum_fold(csum_partial(skb_transport_header(skb),
- thlen, skb->csum));
-
- seq += mss;
- if (copy_destructor) {
- skb->destructor = gso_skb->destructor;
- skb->sk = gso_skb->sk;
- /* {tcp|sock}_wfree() use exact truesize accounting :
- * sum(skb->truesize) MUST be exactly be gso_skb->truesize
- * So we account mss bytes of 'true size' for each segment.
- * The last segment will contain the remaining.
- */
- skb->truesize = mss;
- gso_skb->truesize -= mss;
- }
- skb = skb->next;
- th = tcp_hdr(skb);
-
- th->seq = htonl(seq);
- th->cwr = 0;
- } while (skb->next);
-
- /* Following permits TCP Small Queues to work well with GSO :
- * The callback to TCP stack will be called at the time last frag
- * is freed at TX completion, and not right now when gso_skb
- * is freed by GSO engine
- */
- if (copy_destructor) {
- swap(gso_skb->sk, skb->sk);
- swap(gso_skb->destructor, skb->destructor);
- swap(gso_skb->truesize, skb->truesize);
- }
-
- delta = htonl(oldlen + (skb->tail - skb->transport_header) +
- skb->data_len);
- th->check = ~csum_fold((__force __wsum)((__force u32)th->check +
- (__force u32)delta));
- if (skb->ip_summed != CHECKSUM_PARTIAL)
- th->check = csum_fold(csum_partial(skb_transport_header(skb),
- thlen, skb->csum));
-
-out:
- return segs;
-}
-EXPORT_SYMBOL(tcp_tso_segment);
-
-struct sk_buff **tcp_gro_receive(struct sk_buff **head, struct sk_buff *skb)
-{
- struct sk_buff **pp = NULL;
- struct sk_buff *p;
- struct tcphdr *th;
- struct tcphdr *th2;
- unsigned int len;
- unsigned int thlen;
- __be32 flags;
- unsigned int mss = 1;
- unsigned int hlen;
- unsigned int off;
- int flush = 1;
- int i;
-
- off = skb_gro_offset(skb);
- hlen = off + sizeof(*th);
- th = skb_gro_header_fast(skb, off);
- if (skb_gro_header_hard(skb, hlen)) {
- th = skb_gro_header_slow(skb, hlen, off);
- if (unlikely(!th))
- goto out;
- }
-
- thlen = th->doff * 4;
- if (thlen < sizeof(*th))
- goto out;
-
- hlen = off + thlen;
- if (skb_gro_header_hard(skb, hlen)) {
- th = skb_gro_header_slow(skb, hlen, off);
- if (unlikely(!th))
- goto out;
- }
-
- skb_gro_pull(skb, thlen);
-
- len = skb_gro_len(skb);
- flags = tcp_flag_word(th);
-
- for (; (p = *head); head = &p->next) {
- if (!NAPI_GRO_CB(p)->same_flow)
- continue;
-
- th2 = tcp_hdr(p);
-
- if (*(u32 *)&th->source ^ *(u32 *)&th2->source) {
- NAPI_GRO_CB(p)->same_flow = 0;
- continue;
- }
-
- goto found;
- }
-
- goto out_check_final;
-
-found:
- flush = NAPI_GRO_CB(p)->flush;
- flush |= (__force int)(flags & TCP_FLAG_CWR);
- flush |= (__force int)((flags ^ tcp_flag_word(th2)) &
- ~(TCP_FLAG_CWR | TCP_FLAG_FIN | TCP_FLAG_PSH));
- flush |= (__force int)(th->ack_seq ^ th2->ack_seq);
- for (i = sizeof(*th); i < thlen; i += 4)
- flush |= *(u32 *)((u8 *)th + i) ^
- *(u32 *)((u8 *)th2 + i);
-
- mss = skb_shinfo(p)->gso_size;
-
- flush |= (len - 1) >= mss;
- flush |= (ntohl(th2->seq) + skb_gro_len(p)) ^ ntohl(th->seq);
-
- if (flush || skb_gro_receive(head, skb)) {
- mss = 1;
- goto out_check_final;
- }
-
- p = *head;
- th2 = tcp_hdr(p);
- tcp_flag_word(th2) |= flags & (TCP_FLAG_FIN | TCP_FLAG_PSH);
-
-out_check_final:
- flush = len < mss;
- flush |= (__force int)(flags & (TCP_FLAG_URG | TCP_FLAG_PSH |
- TCP_FLAG_RST | TCP_FLAG_SYN |
- TCP_FLAG_FIN));
-
- if (p && (!NAPI_GRO_CB(skb)->same_flow || flush))
- pp = head;
-
-out:
- NAPI_GRO_CB(skb)->flush |= flush;
-
- return pp;
-}
-EXPORT_SYMBOL(tcp_gro_receive);
-
-int tcp_gro_complete(struct sk_buff *skb)
-{
- struct tcphdr *th = tcp_hdr(skb);
-
- skb->csum_start = skb_transport_header(skb) - skb->head;
- skb->csum_offset = offsetof(struct tcphdr, check);
- skb->ip_summed = CHECKSUM_PARTIAL;
-
- skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count;
-
- if (th->cwr)
- skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
-
- return 0;
-}
-EXPORT_SYMBOL(tcp_gro_complete);
-
#ifdef CONFIG_TCP_MD5SIG
-static unsigned long tcp_md5sig_users;
-static struct tcp_md5sig_pool __percpu *tcp_md5sig_pool;
-static DEFINE_SPINLOCK(tcp_md5sig_pool_lock);
+static struct tcp_md5sig_pool __percpu *tcp_md5sig_pool __read_mostly;
+static DEFINE_MUTEX(tcp_md5sig_mutex);
static void __tcp_free_md5sig_pool(struct tcp_md5sig_pool __percpu *pool)
{
@@ -3132,30 +2899,14 @@ static void __tcp_free_md5sig_pool(struct tcp_md5sig_pool __percpu *pool)
free_percpu(pool);
}
-void tcp_free_md5sig_pool(void)
-{
- struct tcp_md5sig_pool __percpu *pool = NULL;
-
- spin_lock_bh(&tcp_md5sig_pool_lock);
- if (--tcp_md5sig_users == 0) {
- pool = tcp_md5sig_pool;
- tcp_md5sig_pool = NULL;
- }
- spin_unlock_bh(&tcp_md5sig_pool_lock);
- if (pool)
- __tcp_free_md5sig_pool(pool);
-}
-EXPORT_SYMBOL(tcp_free_md5sig_pool);
-
-static struct tcp_md5sig_pool __percpu *
-__tcp_alloc_md5sig_pool(struct sock *sk)
+static void __tcp_alloc_md5sig_pool(void)
{
int cpu;
struct tcp_md5sig_pool __percpu *pool;
pool = alloc_percpu(struct tcp_md5sig_pool);
if (!pool)
- return NULL;
+ return;
for_each_possible_cpu(cpu) {
struct crypto_hash *hash;
@@ -3166,53 +2917,27 @@ __tcp_alloc_md5sig_pool(struct sock *sk)
per_cpu_ptr(pool, cpu)->md5_desc.tfm = hash;
}
- return pool;
+ /* before setting tcp_md5sig_pool, we must commit all writes
+ * to memory. See ACCESS_ONCE() in tcp_get_md5sig_pool()
+ */
+ smp_wmb();
+ tcp_md5sig_pool = pool;
+ return;
out_free:
__tcp_free_md5sig_pool(pool);
- return NULL;
}
-struct tcp_md5sig_pool __percpu *tcp_alloc_md5sig_pool(struct sock *sk)
+bool tcp_alloc_md5sig_pool(void)
{
- struct tcp_md5sig_pool __percpu *pool;
- bool alloc = false;
-
-retry:
- spin_lock_bh(&tcp_md5sig_pool_lock);
- pool = tcp_md5sig_pool;
- if (tcp_md5sig_users++ == 0) {
- alloc = true;
- spin_unlock_bh(&tcp_md5sig_pool_lock);
- } else if (!pool) {
- tcp_md5sig_users--;
- spin_unlock_bh(&tcp_md5sig_pool_lock);
- cpu_relax();
- goto retry;
- } else
- spin_unlock_bh(&tcp_md5sig_pool_lock);
-
- if (alloc) {
- /* we cannot hold spinlock here because this may sleep. */
- struct tcp_md5sig_pool __percpu *p;
-
- p = __tcp_alloc_md5sig_pool(sk);
- spin_lock_bh(&tcp_md5sig_pool_lock);
- if (!p) {
- tcp_md5sig_users--;
- spin_unlock_bh(&tcp_md5sig_pool_lock);
- return NULL;
- }
- pool = tcp_md5sig_pool;
- if (pool) {
- /* oops, it has already been assigned. */
- spin_unlock_bh(&tcp_md5sig_pool_lock);
- __tcp_free_md5sig_pool(p);
- } else {
- tcp_md5sig_pool = pool = p;
- spin_unlock_bh(&tcp_md5sig_pool_lock);
- }
+ if (unlikely(!tcp_md5sig_pool)) {
+ mutex_lock(&tcp_md5sig_mutex);
+
+ if (!tcp_md5sig_pool)
+ __tcp_alloc_md5sig_pool();
+
+ mutex_unlock(&tcp_md5sig_mutex);
}
- return pool;
+ return tcp_md5sig_pool != NULL;
}
EXPORT_SYMBOL(tcp_alloc_md5sig_pool);
@@ -3229,28 +2954,15 @@ struct tcp_md5sig_pool *tcp_get_md5sig_pool(void)
struct tcp_md5sig_pool __percpu *p;
local_bh_disable();
-
- spin_lock(&tcp_md5sig_pool_lock);
- p = tcp_md5sig_pool;
+ p = ACCESS_ONCE(tcp_md5sig_pool);
if (p)
- tcp_md5sig_users++;
- spin_unlock(&tcp_md5sig_pool_lock);
-
- if (p)
- return this_cpu_ptr(p);
+ return __this_cpu_ptr(p);
local_bh_enable();
return NULL;
}
EXPORT_SYMBOL(tcp_get_md5sig_pool);
-void tcp_put_md5sig_pool(void)
-{
- local_bh_enable();
- tcp_free_md5sig_pool();
-}
-EXPORT_SYMBOL(tcp_put_md5sig_pool);
-
int tcp_md5_hash_header(struct tcp_md5sig_pool *hp,
const struct tcphdr *th)
{