[take2 2/4] kevent: network AIO, socket notifications.

Evgeniy Polyakov
2006-08-01T09:11:06Z

This patchset includes socket notifications and network asynchronous IO.
Network AIO is based on kevent and works as usual kevent storage on top
of inode.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>

diff --git a/include/asm-i386/socket.h b/include/asm-i386/socket.h
index 5755d57..d4d2f5c 100644
--- a/include/asm-i386/socket.h
+++ b/include/asm-i386/socket.h
@@ -50,4 +50,6 @@ #define SO_ACCEPTCONN 30
#define SO_PEERSEC 31
#define SO_PASSSEC 34

+#define SO_ASYNC_SOCK 35
+
#endif /* _ASM_SOCKET_H */

diff --git a/include/asm-x86_64/socket.h b/include/asm-x86_64/socket.h
index b467026..fc2b49d 100644
--- a/include/asm-x86_64/socket.h
+++ b/include/asm-x86_64/socket.h
@@ -50,4 +50,6 @@ #define SO_ACCEPTCONN 30
#define SO_PEERSEC 31
#define SO_PASSSEC 34

+#define SO_ASYNC_SOCK 35
+
#endif /* _ASM_SOCKET_H */
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 4307e76..9267873 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1283,6 +1283,8 @@ extern struct sk_buff *skb_recv_datagram
int noblock, int *err);
extern unsigned int datagram_poll(struct file *file, struct socket *sock,
struct poll_table_struct *wait);
+extern int skb_copy_datagram(const struct sk_buff *from,
+ int offset, void *dst, int size);
extern int skb_copy_datagram_iovec(const struct sk_buff *from,
int offset, struct iovec *to,
int size);
diff --git a/include/net/sock.h b/include/net/sock.h
index 324b3ea..c43a153 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -48,6 +48,7 @@ #include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h> /* struct sk_buff */
#include <linux/security.h>
+#include <linux/kevent.h>

#include <linux/filter.h>

@@ -391,6 +392,8 @@ enum sock_flags {
SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
+ SOCK_ASYNC,
+ SOCK_ASYNC_INUSE,
};

static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
@@ -450,6 +453,21 @@ static inline int sk_stream_memory_free(

extern void sk_stream_rfree(struct sk_buff *skb);

+struct socket_alloc {
+ struct socket socket;
+ struct inode vfs_inode;
+};
+
+static inline struct socket *SOCKET_I(struct inode *inode)
+{
+ return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
+}
+
+static inline struct inode *SOCK_INODE(struct socket *socket)
+{
+ return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
+}
+
static inline void sk_stream_set_owner_r(struct sk_buff *skb, struct sock *sk)
{
skb->sk = sk;
@@ -477,6 +495,7 @@ static inline void sk_add_backlog(struct
sk->sk_backlog.tail = skb;
}
skb->next = NULL;
+ kevent_socket_notify(sk, KEVENT_SOCKET_RECV);
}

#define sk_wait_event(__sk, __timeo, __condition) \
@@ -548,6 +567,12 @@ struct proto {

int (*backlog_rcv) (struct sock *sk,
struct sk_buff *skb);
+
+ int (*async_recv) (struct sock *sk,
+ void *dst, size_t size);
+ int (*async_send) (struct sock *sk,
+ struct page **pages, unsigned int poffset,
+ size_t size);

/* Keeping track of sk's, looking them up, and port selection methods. */
void (*hash)(struct sock *sk);
@@ -679,21 +704,6 @@ static inline struct kiocb *siocb_to_kio
return si->kiocb;
}

-struct socket_alloc {
- struct socket socket;
- struct inode vfs_inode;
-};
-
-static inline struct socket *SOCKET_I(struct inode *inode)
-{
- return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
-}
-
-static inline struct inode *SOCK_INODE(struct socket *socket)
-{
- return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
-}
-
extern void __sk_stream_mem_reclaim(struct sock *sk);
extern int sk_stream_mem_schedule(struct sock *sk, int size, int kind);

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 0720bdd..5a1899b 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -364,6 +364,8 @@ extern int compat_tcp_setsockopt(struc
int level, int optname,
char __user *optval, int optlen);
extern void tcp_set_keepalive(struct sock *sk, int val);
+extern int tcp_async_recv(struct sock *sk, void *dst, size_t size);
+extern int tcp_async_send(struct sock *sk, struct page **pages, unsigned int poffset, size_t size);
extern int tcp_recvmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg,
size_t len, int nonblock,
@@ -857,6 +859,7 @@ static inline int tcp_prequeue(struct so
tp->ucopy.memory = 0;
} else if (skb_queue_len(&tp->ucopy.prequeue) == 1) {
wake_up_interruptible(sk->sk_sleep);
+ kevent_socket_notify(sk, KEVENT_SOCKET_RECV|KEVENT_SOCKET_SEND);
if (!inet_csk_ack_scheduled(sk))
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
(3 * TCP_RTO_MIN) / 4,
diff --git a/kernel/kevent/kevent_naio.c b/kernel/kevent/kevent_naio.c
new file mode 100644
index 0000000..1c71021
--- /dev/null
+++ b/kernel/kevent/kevent_naio.c
@@ -0,0 +1,239 @@
+/*
+ * kevent_naio.c
+ *
+ * 2006 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/kevent.h>
+
+#include <net/sock.h>
+#include <net/tcp_states.h>
+
+static int kevent_naio_enqueue(struct kevent *k);
+static int kevent_naio_dequeue(struct kevent *k);
+static int kevent_naio_callback(struct kevent *k);
+
+static int kevent_naio_setup_aio(int ctl_fd, int s, void __user *buf,
+ size_t size, u32 event)
+{
+ struct kevent_user *u;
+ struct file *file;
+ int err, fput_needed;
+ struct ukevent uk;
+
+ file = fget_light(ctl_fd, &fput_needed);
+ if (!file)
+ return -ENODEV;
+
+ u = file->private_data;
+ if (!u) {
+ err = -EINVAL;
+ goto err_out_fput;
+ }
+
+ memset(&uk, 0, sizeof(struct ukevent));
+ uk.type = KEVENT_NAIO;
+ uk.ptr = buf;
+ uk.req_flags = KEVENT_REQ_ONESHOT;
+ uk.event = event;
+ uk.id.raw[0] = s;
+ uk.id.raw[1] = size;
+
+ err = kevent_user_add_ukevent(&uk, u);
+
+err_out_fput:
+ fput_light(file, fput_needed);
+ return err;
+}
+
+asmlinkage long sys_aio_recv(int ctl_fd, int s, void __user *buf,
+ size_t size, unsigned flags)
+{
+ return kevent_naio_setup_aio(ctl_fd, s, buf, size, KEVENT_SOCKET_RECV);
+}
+
+asmlinkage long sys_aio_send(int ctl_fd, int s, void __user *buf,
+ size_t size, unsigned flags)
+{
+ return kevent_naio_setup_aio(ctl_fd, s, buf, size, KEVENT_SOCKET_SEND);
+}
+
+static int kevent_naio_enqueue(struct kevent *k)
+{
+ int err, i;
+ struct page **page;
+ void *addr;
+ unsigned int size = k->event.id.raw[1];
+ int num = size/PAGE_SIZE;
+ struct file *file;
+ struct sock *sk = NULL;
+ int fput_needed;
+
+ file = fget_light(k->event.id.raw[0], &fput_needed);
+ if (!file)
+ return -ENODEV;
+
+ err = -EINVAL;
+ if (!file->f_dentry || !file->f_dentry->d_inode)
+ goto err_out_fput;
+
+ sk = SOCKET_I(file->f_dentry->d_inode)->sk;
+
+ err = -ESOCKTNOSUPPORT;
+ if (!sk || !sk->sk_prot->async_recv || !sk->sk_prot->async_send ||
+ !sock_flag(sk, SOCK_ASYNC))
+ goto err_out_fput;
+
+ addr = k->event.ptr;
+ if (((unsigned long)addr & PAGE_MASK) != (unsigned long)addr)
+ num++;
+
+ page = kmalloc(sizeof(struct page *) * num, GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+
+ down_read(&current->mm->mmap_sem);
+ err = get_user_pages(current, current->mm, (unsigned long)addr,
+ num, 1, 0, page, NULL);
+ up_read(&current->mm->mmap_sem);
+ if (err <= 0)
+ goto err_out_free;
+ num = err;
+
+ k->event.ret_data[0] = num;
+ k->event.ret_data[1] = offset_in_page(k->event.ptr);
+ k->priv = page;
+
+ sk->sk_allocation = GFP_ATOMIC;
+
+ spin_lock_bh(&sk->sk_lock.slock);
+ err = kevent_socket_enqueue(k);
+ spin_unlock_bh(&sk->sk_lock.slock);
+ if (err)
+ goto err_out_put_pages;
+
+ fput_light(file, fput_needed);
+
+ return err;
+
+err_out_put_pages:
+ for (i=0; i<num; ++i)
+ page_cache_release(page[i]);
+err_out_free:
+ kfree(page);
+err_out_fput:
+ fput_light(file, fput_needed);
+
+ return err;
+}
+
+static int kevent_naio_dequeue(struct kevent *k)
+{
+ int err, i, num;
+ struct page **page = k->priv;
+
+ num = k->event.ret_data[0];
+
+ err = kevent_socket_dequeue(k);
+
+ for (i=0; i<num; ++i)
+ page_cache_release(page[i]);
+
+ kfree(k->priv);
+ k->priv = NULL;
+
+ return err;
+}
+
+static int kevent_naio_callback(struct kevent *k)
+{
+ struct inode *inode = k->st->origin;
+ struct sock *sk = SOCKET_I(inode)->sk;
+ unsigned int size = k->event.id.raw[1];
+ unsigned int off = k->event.ret_data[1];
+ struct page **pages = k->priv, *page;
+ int ready = 0, num = off/PAGE_SIZE, err = 0, send = 0;
+ void *ptr, *optr;
+ unsigned int len;
+
+ if (!sock_flag(sk, SOCK_ASYNC))
+ return -1;
+
+ if (k->event.event & KEVENT_SOCKET_SEND)
+ send = 1;
+ else if (!(k->event.event & KEVENT_SOCKET_RECV))
+ return -EINVAL;
+
+ /*
+ * sk_prot->async_*() can return either number of bytes processed,
+ * or negative error value, or zero if socket is closed.
+ */
+
+ if (!send) {
+ page = pages[num];
+
+ optr = ptr = kmap_atomic(page, KM_IRQ0);
+ if (!ptr)
+ return -ENOMEM;
+
+ ptr += off % PAGE_SIZE;
+ len = min_t(unsigned int, PAGE_SIZE - (ptr - optr), size);
+
+ err = sk->sk_prot->async_recv(sk, ptr, len);
+
+ kunmap_atomic(optr, KM_IRQ0);
+ } else {
+ len = size;
+ err = sk->sk_prot->async_send(sk, pages, off, size);
+ }
+
+ if (err > 0) {
+ num++;
+ size -= err;
+ off += err;
+ }
+
+ k->event.ret_data[1] = off;
+ k->event.id.raw[1] = size;
+
+ if (err == 0 || (err < 0 && err != -EAGAIN))
+ ready = -1;
+
+ if (!size)
+ ready = 1;
+#if 0
+ printk("%s: sk=%p, k=%p, size=%4u, off=%4u, err=%3d, ready=%1d.\n",
+ __func__, sk, k, size, off, err, ready);
+#endif
+
+ return ready;
+}
+
+int kevent_init_naio(struct kevent *k)
+{
+ k->enqueue = &kevent_naio_enqueue;
+ k->dequeue = &kevent_naio_dequeue;
+ k->callback = &kevent_naio_callback;
+ return 0;
+}
diff --git a/kernel/kevent/kevent_socket.c b/kernel/kevent/kevent_socket.c
new file mode 100644
index 0000000..c230aaa
--- /dev/null
+++ b/kernel/kevent/kevent_socket.c
@@ -0,0 +1,125 @@
+/*
+ * kevent_socket.c
+ *
+ * 2006 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/file.h>
+#include <linux/tcp.h>
+#include <linux/kevent.h>
+
+#include <net/sock.h>
+#include <net/request_sock.h>
+#include <net/inet_connection_sock.h>
+
+static int kevent_socket_callback(struct kevent *k)
+{
+ struct inode *inode = k->st->origin;
+ struct sock *sk = SOCKET_I(inode)->sk;
+ int rmem;
+
+ if (k->event.event & KEVENT_SOCKET_RECV) {
+ int ret = 0;
+
+ if ((rmem = atomic_read(&sk->sk_rmem_alloc)) > 0 ||
+ !skb_queue_empty(&sk->sk_receive_queue))
+ ret = 1;
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ ret = 1;
+ if (ret)
+ return ret;
+ }
+ if ((k->event.event & KEVENT_SOCKET_ACCEPT) &&
+ (!reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ||
+ reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue))) {
+ k->event.ret_data[1] = reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue);
+ return 1;
+ }
+
+ return 0;
+}
+
+int kevent_socket_enqueue(struct kevent *k)
+{
+ struct file *file;
+ struct inode *inode;
+ int err, fput_needed;
+
+ file = fget_light(k->event.id.raw[0], &fput_needed);
+ if (!file)
+ return -ENODEV;
+
+ err = -EINVAL;
+ if (!file->f_dentry || !file->f_dentry->d_inode)
+ goto err_out_fput;
+
+ inode = igrab(file->f_dentry->d_inode);
+ if (!inode)
+ goto err_out_fput;
+
+ err = kevent_storage_enqueue(&inode->st, k);
+ if (err)
+ goto err_out_iput;
+
+ err = k->callback(k);
+ if (err)
+ goto err_out_dequeue;
+
+ fput_light(file, fput_needed);
+ return err;
+
+err_out_dequeue:
+ kevent_storage_dequeue(k->st, k);
+err_out_iput:
+ iput(inode);
+err_out_fput:
+ fput_light(file, fput_needed);
+ return err;
+}
+
+int kevent_socket_dequeue(struct kevent *k)
+{
+ struct inode *inode = k->st->origin;
+
+ kevent_storage_dequeue(k->st, k);
+ iput(inode);
+
+ return 0;
+}
+
+int kevent_init_socket(struct kevent *k)
+{
+ k->enqueue = &kevent_socket_enqueue;
+ k->dequeue = &kevent_socket_dequeue;
+ k->callback = &kevent_socket_callback;
+ return 0;
+}
+
+void kevent_socket_notify(struct sock *sk, u32 event)
+{
+ if (sk->sk_socket && !test_and_set_bit(SOCK_ASYNC_INUSE, &sk->sk_flags)) {
+ kevent_storage_ready(&SOCK_INODE(sk->sk_socket)->st, NULL, event);
+ sock_reset_flag(sk, SOCK_ASYNC_INUSE);
+ }
+}
diff --git a/net/core/datagram.c b/net/core/datagram.c
index aecddcc..493245b 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -236,6 +236,60 @@ void skb_kill_datagram(struct sock *sk,
EXPORT_SYMBOL(skb_kill_datagram);

/**
+ * skb_copy_datagram - Copy a datagram.
+ * @skb: buffer to copy
+ * @offset: offset in the buffer to start copying from
+ * @to: pointer to copy to
+ * @len: amount of data to copy from buffer to iovec
+ */
+int skb_copy_datagram(const struct sk_buff *skb, int offset,
+ void *to, int len)
+{
+ int i, fraglen, end = 0;
+ struct sk_buff *next = skb_shinfo(skb)->frag_list;
+
+ if (!len)
+ return 0;
+
+next_skb:
+ fraglen = skb_headlen(skb);
+ i = -1;
+
+ while (1) {
+ int start = end;
+
+ if ((end += fraglen) > offset) {
+ int copy = end - offset, o = offset - start;
+
+ if (copy > len)
+ copy = len;
+ if (i == -1)
+ memcpy(to, skb->data + o, copy);
+ else {
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+ struct page *page = frag->page;
+ void *p = kmap(page) + frag->page_offset + o;
+ memcpy(to, p, copy);
+ kunmap(page);
+ }
+ if (!(len -= copy))
+ return 0;
+ offset += copy;
+ }
+ if (++i >= skb_shinfo(skb)->nr_frags)
+ break;
+ fraglen = skb_shinfo(skb)->frags[i].size;
+ }
+ if (next) {
+ skb = next;
+ BUG_ON(skb_shinfo(skb)->frag_list);
+ next = skb->next;
+ goto next_skb;
+ }
+ return -EFAULT;
+}
+
+/**
* skb_copy_datagram_iovec - Copy a datagram to an iovec.
* @skb: buffer to copy
* @offset: offset in the buffer to start copying from
@@ -530,6 +584,7 @@ unsigned int datagram_poll(struct file *

EXPORT_SYMBOL(datagram_poll);
EXPORT_SYMBOL(skb_copy_and_csum_datagram_iovec);
+EXPORT_SYMBOL(skb_copy_datagram);
EXPORT_SYMBOL(skb_copy_datagram_iovec);
EXPORT_SYMBOL(skb_free_datagram);
EXPORT_SYMBOL(skb_recv_datagram);
diff --git a/net/core/sock.c b/net/core/sock.c
index 51fcfbc..9922373 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -617,6 +617,16 @@ #endif
spin_unlock_bh(&sk->sk_lock.slock);
ret = -ENONET;
break;
+#ifdef CONFIG_KEVENT_SOCKET
+ case SO_ASYNC_SOCK:
+ spin_lock_bh(&sk->sk_lock.slock);
+ if (valbool)
+ sock_set_flag(sk, SOCK_ASYNC);
+ else
+ sock_reset_flag(sk, SOCK_ASYNC);
+ spin_unlock_bh(&sk->sk_lock.slock);
+ break;
+#endif

case SO_PASSSEC:
if (valbool)
@@ -1406,6 +1416,7 @@ static void sock_def_wakeup(struct sock
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible_all(sk->sk_sleep);
read_unlock(&sk->sk_callback_lock);
+ kevent_socket_notify(sk, KEVENT_SOCKET_RECV|KEVENT_SOCKET_SEND);
}

static void sock_def_error_report(struct sock *sk)
@@ -1415,6 +1426,7 @@ static void sock_def_error_report(struct
wake_up_interruptible(sk->sk_sleep);
sk_wake_async(sk,0,POLL_ERR);
read_unlock(&sk->sk_callback_lock);
+ kevent_socket_notify(sk, KEVENT_SOCKET_RECV|KEVENT_SOCKET_SEND);
}

static void sock_def_readable(struct sock *sk, int len)
@@ -1424,6 +1436,7 @@ static void sock_def_readable(struct soc
wake_up_interruptible(sk->sk_sleep);
sk_wake_async(sk,1,POLL_IN);
read_unlock(&sk->sk_callback_lock);
+ kevent_socket_notify(sk, KEVENT_SOCKET_RECV|KEVENT_SOCKET_SEND);
}

static void sock_def_write_space(struct sock *sk)
@@ -1443,6 +1456,7 @@ static void sock_def_write_space(struct
}

read_unlock(&sk->sk_callback_lock);
+ kevent_socket_notify(sk, KEVENT_SOCKET_SEND|KEVENT_SOCKET_RECV);
}

static void sock_def_destruct(struct sock *sk)
@@ -1559,8 +1573,10 @@ void fastcall release_sock(struct sock *
if (sk->sk_backlog.tail)
__release_sock(sk);
sk->sk_lock.owner = NULL;
- if (waitqueue_active(&sk->sk_lock.wq))
+ if (waitqueue_active(&sk->sk_lock.wq)) {
wake_up(&sk->sk_lock.wq);
+ kevent_socket_notify(sk, KEVENT_SOCKET_RECV|KEVENT_SOCKET_SEND);
+ }
spin_unlock_bh(&sk->sk_lock.slock);
}
EXPORT_SYMBOL(release_sock);
diff --git a/net/core/stream.c b/net/core/stream.c
index d1d7dec..2878c2a 100644
--- a/net/core/stream.c
+++ b/net/core/stream.c
@@ -36,6 +36,7 @@ void sk_stream_write_space(struct sock *
wake_up_interruptible(sk->sk_sleep);
if (sock->fasync_list && !(sk->sk_shutdown & SEND_SHUTDOWN))
sock_wake_async(sock, 2, POLL_OUT);
+ kevent_socket_notify(sk, KEVENT_SOCKET_SEND|KEVENT_SOCKET_RECV);
}
}

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index f6a2d92..e878a41 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -206,6 +206,7 @@
* lingertime == 0 (RFC 793 ABORT Call)
* Hirokazu Takahashi : Use copy_from_user() instead of
* csum_and_copy_from_user() if possible.
+ * Evgeniy Polyakov : Network asynchronous IO.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -1085,6 +1086,301 @@ int tcp_read_sock(struct sock *sk, read_
}

/*
+ * Must be called with locked sock.
+ */
+int tcp_async_send(struct sock *sk, struct page **pages, unsigned int poffset, size_t len)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ int mss_now, size_goal;
+ int err = -EAGAIN;
+ ssize_t copied;
+
+ /* Wait for a connection to finish. */
+ if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT))
+ goto out_err;
+
+ clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
+
+ mss_now = tcp_current_mss(sk, 1);
+ size_goal = tp->xmit_size_goal;
+ copied = 0;
+
+ err = -EPIPE;
+ if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN) || sock_flag(sk, SOCK_DONE) ||
+ (sk->sk_state == TCP_CLOSE) || (atomic_read(&sk->sk_refcnt) == 1))
+ goto do_error;
+
+ while (len > 0) {
+ struct sk_buff *skb = sk->sk_write_queue.prev;
+ struct page *page = pages[poffset / PAGE_SIZE];
+ int copy, i, can_coalesce;
+ int offset = poffset % PAGE_SIZE;
+ int size = min_t(size_t, len, PAGE_SIZE - offset);
+
+ if (!sk->sk_send_head || (copy = size_goal - skb->len) <= 0) {
+new_segment:
+ if (!sk_stream_memory_free(sk))
+ goto wait_for_sndbuf;
+
+ skb = sk_stream_alloc_pskb(sk, 0, 0,
+ sk->sk_allocation);
+ if (!skb)
+ goto wait_for_memory;
+
+ skb_entail(sk, tp, skb);
+ copy = size_goal;
+ }
+
+ if (copy > size)
+ copy = size;
+
+ i = skb_shinfo(skb)->nr_frags;
+ can_coalesce = skb_can_coalesce(skb, i, page, offset);
+ if (!can_coalesce && i >= MAX_SKB_FRAGS) {
+ tcp_mark_push(tp, skb);
+ goto new_segment;
+ }
+ if (!sk_stream_wmem_schedule(sk, copy))
+ goto wait_for_memory;
+
+ if (can_coalesce) {
+ skb_shinfo(skb)->frags[i - 1].size += copy;
+ } else {
+ get_page(page);
+ skb_fill_page_desc(skb, i, page, offset, copy);
+ }
+
+ skb->len += copy;
+ skb->data_len += copy;
+ skb->truesize += copy;
+ sk->sk_wmem_queued += copy;
+ sk->sk_forward_alloc -= copy;
+ skb->ip_summed = CHECKSUM_HW;
+ tp->write_seq += copy;
+ TCP_SKB_CB(skb)->end_seq += copy;
+ skb_shinfo(skb)->gso_segs = 0;
+
+ if (!copied)
+ TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_PSH;
+
+ copied += copy;
+ poffset += copy;
+ if (!(len -= copy))
+ goto out;
+
+ if (skb->len < mss_now)
+ continue;
+
+ if (forced_push(tp)) {
+ tcp_mark_push(tp, skb);
+ __tcp_push_pending_frames(sk, tp, mss_now, TCP_NAGLE_PUSH);
+ } else if (skb == sk->sk_send_head)
+ tcp_push_one(sk, mss_now);
+ continue;
+
+wait_for_sndbuf:
+ set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+wait_for_memory:
+ if (copied)
+ tcp_push(sk, tp, 0, mss_now, TCP_NAGLE_PUSH);
+
+ err = -EAGAIN;
+ goto do_error;
+ }
+
+out:
+ if (copied)
+ tcp_push(sk, tp, 0, mss_now, tp->nonagle);
+ return copied;
+
+do_error:
+ if (copied)
+ goto out;
+out_err:
+ return sk_stream_error(sk, 0, err);
+}
+
+/*
+ * Must be called with locked sock.
+ */
+int tcp_async_recv(struct sock *sk, void *dst, size_t len)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ int copied = 0;
+ u32 *seq;
+ unsigned long used;
+ int err;
+ int target; /* Read at least this many bytes */
+ int copied_early = 0;
+
+ TCP_CHECK_TIMER(sk);
+
+ err = -ENOTCONN;
+ if (sk->sk_state == TCP_LISTEN)
+ goto out;
+
+ seq = &tp->copied_seq;
+
+ target = sock_rcvlowat(sk, 0, len);
+
+ do {
+ struct sk_buff *skb;
+ u32 offset;
+
+ /* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */
+ if (tp->urg_data && tp->urg_seq == *seq) {
+ if (copied)
+ break;
+ }
+
+ /* Next get a buffer. */
+
+ skb = skb_peek(&sk->sk_receive_queue);
+ do {
+ if (!skb)
+ break;
+
+ /* Now that we have two receive queues this
+ * shouldn't happen.
+ */
+ if (before(*seq, TCP_SKB_CB(skb)->seq)) {
+ printk(KERN_INFO "async_recv bug: copied %X "
+ "seq %X\n", *seq, TCP_SKB_CB(skb)->seq);
+ break;
+ }
+ offset = *seq - TCP_SKB_CB(skb)->seq;
+ if (skb->h.th->syn)
+ offset--;
+ if (offset < skb->len)
+ goto found_ok_skb;
+ if (skb->h.th->fin)
+ goto found_fin_ok;
+ skb = skb->next;
+ } while (skb != (struct sk_buff *)&sk->sk_receive_queue);
+
+ if (copied)
+ break;
+
+ if (sock_flag(sk, SOCK_DONE))
+ break;
+
+ if (sk->sk_err) {
+ copied = sock_error(sk);
+ break;
+ }
+
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ break;
+
+ if (sk->sk_state == TCP_CLOSE) {
+ if (!sock_flag(sk, SOCK_DONE)) {
+ /* This occurs when user tries to read
+ * from never connected socket.
+ */
+ copied = -ENOTCONN;
+ break;
+ }
+ break;
+ }
+
+ copied = -EAGAIN;
+ break;
+
+ found_ok_skb:
+ /* Ok so how much can we use? */
+ used = skb->len - offset;
+ if (len < used)
+ used = len;
+
+ /* Do we have urgent data here? */
+ if (tp->urg_data) {
+ u32 urg_offset = tp->urg_seq - *seq;
+ if (urg_offset < used) {
+ if (!urg_offset) {
+ if (!sock_flag(sk, SOCK_URGINLINE)) {
+ ++*seq;
+ offset++;
+ used--;
+ if (!used)
+ goto skip_copy;
+ }
+ } else
+ used = urg_offset;
+ }
+ }
+#ifdef CONFIG_NET_DMA
+ if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
+ tp->ucopy.dma_chan = get_softnet_dma();
+
+ if (tp->ucopy.dma_chan) {
+ tp->ucopy.dma_cookie = dma_skb_copy_datagram_iovec(
+ tp->ucopy.dma_chan, skb, offset,
+ msg->msg_iov, used,
+ tp->ucopy.pinned_list);
+
+ if (tp->ucopy.dma_cookie < 0) {
+
+ printk(KERN_ALERT "dma_cookie < 0\n");
+
+ /* Exception. Bailout! */
+ if (!copied)
+ copied = -EFAULT;
+ break;
+ }
+ if ((offset + used) == skb->len)
+ copied_early = 1;
+
+ } else
+#endif
+ {
+ err = skb_copy_datagram(skb, offset, dst, used);
+ if (err) {
+ /* Exception. Bailout! */
+ if (!copied)
+ copied = -EFAULT;
+ break;
+ }
+ }
+
+ *seq += used;
+ copied += used;
+ len -= used;
+ dst += used;
+
+ tcp_rcv_space_adjust(sk);
+
+skip_copy:
+ if (tp->urg_data && after(tp->copied_seq, tp->urg_seq)) {
+ tp->urg_data = 0;
+ tcp_fast_path_check(sk, tp);
+ }
+ if (used + offset < skb->len)
+ continue;
+
+ if (skb->h.th->fin)
+ goto found_fin_ok;
+ sk_eat_skb(sk, skb, copied_early);
+ continue;
+
+ found_fin_ok:
+ /* Process the FIN. */
+ ++*seq;
+ sk_eat_skb(sk, skb, copied_early);
+ break;
+ } while (len > 0);
+
+ /* Clean up data we have read: This will do ACK frames. */
+ tcp_cleanup_rbuf(sk, copied);
+
+ TCP_CHECK_TIMER(sk);
+ return copied;
+
+out:
+ TCP_CHECK_TIMER(sk);
+ return err;
+}
+
+/*
* This routine copies from a sock struct into the user buffer.
*
* Technical note: in 2.3 we work on _locked_ socket, so that
@@ -2342,6 +2638,8 @@ EXPORT_SYMBOL(tcp_getsockopt);
EXPORT_SYMBOL(tcp_ioctl);
EXPORT_SYMBOL(tcp_poll);
EXPORT_SYMBOL(tcp_read_sock);
+EXPORT_SYMBOL(tcp_async_recv);
+EXPORT_SYMBOL(tcp_async_send);
EXPORT_SYMBOL(tcp_recvmsg);
EXPORT_SYMBOL(tcp_sendmsg);
EXPORT_SYMBOL(tcp_sendpage);
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 738dad9..f70d045 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3112,6 +3112,7 @@ static void tcp_ofo_queue(struct sock *s

__skb_unlink(skb, &tp->out_of_order_queue);
__skb_queue_tail(&sk->sk_receive_queue, skb);
+ kevent_socket_notify(sk, KEVENT_SOCKET_RECV);
tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq;
if(skb->h.th->fin)
tcp_fin(skb, sk, skb->h.th);
@@ -3955,7 +3956,8 @@ int tcp_rcv_established(struct sock *sk,
int copied_early = 0;

if (tp->copied_seq == tp->rcv_nxt &&
- len - tcp_header_len <= tp->ucopy.len) {
+ len - tcp_header_len <= tp->ucopy.len &&
+ !sock_async(sk)) {
#ifdef CONFIG_NET_DMA
if (tcp_dma_try_early_copy(sk, skb, tcp_header_len)) {
copied_early = 1;
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index f6f39e8..ae4f23c 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -61,6 +61,7 @@ #include <linux/cache.h>
#include <linux/jhash.h>
#include <linux/init.h>
#include <linux/times.h>
+#include <linux/kevent.h>

#include <net/icmp.h>
#include <net/inet_hashtables.h>
@@ -868,6 +869,7 @@ #endif
reqsk_free(req);
} else {
inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
+ kevent_socket_notify(sk, KEVENT_SOCKET_ACCEPT);
}
return 0;

@@ -1108,24 +1110,30 @@ process:

skb->dev = NULL;

- bh_lock_sock_nested(sk);
ret = 0;
- if (!sock_owned_by_user(sk)) {
+ if (sock_async(sk)) {
+ spin_lock_bh(&sk->sk_lock.slock);
+ ret = tcp_v4_do_rcv(sk, skb);
+ spin_unlock_bh(&sk->sk_lock.slock);
+ } else {
+ bh_lock_sock_nested(sk);
+ if (!sock_owned_by_user(sk)) {
#ifdef CONFIG_NET_DMA
- struct tcp_sock *tp = tcp_sk(sk);
- if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
- tp->ucopy.dma_chan = get_softnet_dma();
- if (tp->ucopy.dma_chan)
- ret = tcp_v4_do_rcv(sk, skb);
- else
+ struct tcp_sock *tp = tcp_sk(sk);
+ if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
+ tp->ucopy.dma_chan = get_softnet_dma();
+ if (tp->ucopy.dma_chan)
+ ret = tcp_v4_do_rcv(sk, skb);
+ else
#endif
- {
- if (!tcp_prequeue(sk, skb))
- ret = tcp_v4_do_rcv(sk, skb);
- }
- } else
- sk_add_backlog(sk, skb);
- bh_unlock_sock(sk);
+ {
+ if (!tcp_prequeue(sk, skb))
+ ret = tcp_v4_do_rcv(sk, skb);
+ }
+ } else
+ sk_add_backlog(sk, skb);
+ bh_unlock_sock(sk);
+ }

sock_put(sk);

@@ -1849,6 +1857,8 @@ struct proto tcp_prot = {
.getsockopt = tcp_getsockopt,
.sendmsg = tcp_sendmsg,
.recvmsg = tcp_recvmsg,
+ .async_recv = tcp_async_recv,
+ .async_send = tcp_async_send,
.backlog_rcv = tcp_v4_do_rcv,
.hash = tcp_v4_hash,
.unhash = tcp_unhash,
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 923989d..a5d3ac8 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1230,22 +1230,28 @@ process:

skb->dev = NULL;

- bh_lock_sock(sk);
ret = 0;
- if (!sock_owned_by_user(sk)) {
+ if (sock_async(sk)) {
+ spin_lock_bh(&sk->sk_lock.slock);
+ ret = tcp_v4_do_rcv(sk, skb);
+ spin_unlock_bh(&sk->sk_lock.slock);
+ } else {
+ bh_lock_sock(sk);
+ if (!sock_owned_by_user(sk)) {
#ifdef CONFIG_NET_DMA
- struct tcp_sock *tp = tcp_sk(sk);
- if (tp->ucopy.dma_chan)
- ret = tcp_v6_do_rcv(sk, skb);
- else
-#endif
- {
- if (!tcp_prequeue(sk, skb))
+ struct tcp_sock *tp = tcp_sk(sk);
+ if (tp->ucopy.dma_chan)
ret = tcp_v6_do_rcv(sk, skb);
- }
- } else
- sk_add_backlog(sk, skb);
- bh_unlock_sock(sk);
+ else
+#endif
+ {
+ if (!tcp_prequeue(sk, skb))
+ ret = tcp_v6_do_rcv(sk, skb);
+ }
+ } else
+ sk_add_backlog(sk, skb);
+ bh_unlock_sock(sk);
+ }

sock_put(sk);
return ret ? -1 : 0;
@@ -1596,6 +1602,8 @@ struct proto tcpv6_prot = {
.getsockopt = tcp_getsockopt,
.sendmsg = tcp_sendmsg,
.recvmsg = tcp_recvmsg,
+ .async_recv = tcp_async_recv,
+ .async_send = tcp_async_send,
.backlog_rcv = tcp_v6_do_rcv,
.hash = tcp_v6_hash,
.unhash = tcp_unhash,