proto_ops: Add locked held versions of sendmsg and sendpage
Add new proto_ops sendmsg_locked and sendpage_locked that can be
called when the socket lock is already held. Correspondingly, add
kernel_sendmsg_locked and kernel_sendpage_locked as front end
functions.
These functions will be used in zero proxy so that we can take
the socket lock in a ULP sendmsg/sendpage and then directly call the
backend transport proto_ops functions.
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/net.h b/include/linux/net.h
index dda2cc9..b5c15b3 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -190,8 +190,16 @@
struct pipe_inode_info *pipe, size_t len, unsigned int flags);
int (*set_peek_off)(struct sock *sk, int val);
int (*peek_len)(struct socket *sock);
+
+ /* The following functions are called internally by kernel with
+ * sock lock already held.
+ */
int (*read_sock)(struct sock *sk, read_descriptor_t *desc,
sk_read_actor_t recv_actor);
+ int (*sendpage_locked)(struct sock *sk, struct page *page,
+ int offset, size_t size, int flags);
+ int (*sendmsg_locked)(struct sock *sk, struct msghdr *msg,
+ size_t size);
};
#define DECLARE_SOCKADDR(type, dst, src) \
@@ -279,6 +287,8 @@
int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
size_t num, size_t len);
+int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
+ struct kvec *vec, size_t num, size_t len);
int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
size_t num, size_t len, int flags);
@@ -297,6 +307,8 @@
unsigned int optlen);
int kernel_sendpage(struct socket *sock, struct page *page, int offset,
size_t size, int flags);
+int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
+ size_t size, int flags);
int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how);
diff --git a/include/net/sock.h b/include/net/sock.h
index 7c0632c..393c38e 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1582,11 +1582,14 @@
int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
+int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
int sock_no_mmap(struct file *file, struct socket *sock,
struct vm_area_struct *vma);
ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
size_t size, int flags);
+ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
+ int offset, size_t size, int flags);
/*
* Functions to fill in entries in struct proto_ops when a protocol
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 3ecb628..bb1881b 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -350,8 +350,11 @@
int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw);
int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
+int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size);
int tcp_sendpage(struct sock *sk, struct page *page, int offset, size_t size,
int flags);
+int tcp_sendpage_locked(struct sock *sk, struct page *page, int offset,
+ size_t size, int flags);
ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset,
size_t size, int flags);
void tcp_release_cb(struct sock *sk);
diff --git a/net/core/sock.c b/net/core/sock.c
index ac2a404..742f68c 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2500,6 +2500,12 @@
}
EXPORT_SYMBOL(sock_no_sendmsg);
+int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
+{
+ return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(sock_no_sendmsg_locked);
+
int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
int flags)
{
@@ -2528,6 +2534,22 @@
}
EXPORT_SYMBOL(sock_no_sendpage);
+ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
+ int offset, size_t size, int flags)
+{
+ ssize_t res;
+ struct msghdr msg = {.msg_flags = flags};
+ struct kvec iov;
+ char *kaddr = kmap(page);
+
+ iov.iov_base = kaddr + offset;
+ iov.iov_len = size;
+ res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
+ kunmap(page);
+ return res;
+}
+EXPORT_SYMBOL(sock_no_sendpage_locked);
+
/*
* Default Socket Callbacks
*/
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 5ce44fb..f0103ff 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -944,6 +944,8 @@
.sendpage = inet_sendpage,
.splice_read = tcp_splice_read,
.read_sock = tcp_read_sock,
+ .sendmsg_locked = tcp_sendmsg_locked,
+ .sendpage_locked = tcp_sendpage_locked,
.peek_len = tcp_peek_len,
#ifdef CONFIG_COMPAT
.compat_setsockopt = compat_sock_common_setsockopt,
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 5326b50..9dd6f4d 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1046,23 +1046,29 @@
}
EXPORT_SYMBOL_GPL(do_tcp_sendpages);
-int tcp_sendpage(struct sock *sk, struct page *page, int offset,
- size_t size, int flags)
+int tcp_sendpage_locked(struct sock *sk, struct page *page, int offset,
+ size_t size, int flags)
{
- ssize_t res;
-
if (!(sk->sk_route_caps & NETIF_F_SG) ||
!sk_check_csum_caps(sk))
return sock_no_sendpage(sk->sk_socket, page, offset, size,
flags);
- lock_sock(sk);
-
tcp_rate_check_app_limited(sk); /* is sending application-limited? */
- res = do_tcp_sendpages(sk, page, offset, size, flags);
+ return do_tcp_sendpages(sk, page, offset, size, flags);
+}
+
+int tcp_sendpage(struct sock *sk, struct page *page, int offset,
+ size_t size, int flags)
+{
+ int ret;
+
+ lock_sock(sk);
+ ret = tcp_sendpage_locked(sk, page, offset, size, flags);
release_sock(sk);
- return res;
+
+ return ret;
}
EXPORT_SYMBOL(tcp_sendpage);
@@ -1156,7 +1162,7 @@
return err;
}
-int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
+int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
@@ -1167,8 +1173,6 @@
bool sg;
long timeo;
- lock_sock(sk);
-
flags = msg->msg_flags;
if (unlikely(flags & MSG_FASTOPEN || inet_sk(sk)->defer_connect)) {
err = tcp_sendmsg_fastopen(sk, msg, &copied_syn, size);
@@ -1377,7 +1381,6 @@
tcp_push(sk, flags, mss_now, tp->nonagle, size_goal);
}
out_nopush:
- release_sock(sk);
return copied + copied_syn;
do_fault:
@@ -1401,9 +1404,19 @@
sk->sk_write_space(sk);
tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED);
}
- release_sock(sk);
return err;
}
+
+int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
+{
+ int ret;
+
+ lock_sock(sk);
+ ret = tcp_sendmsg_locked(sk, msg, size);
+ release_sock(sk);
+
+ return ret;
+}
EXPORT_SYMBOL(tcp_sendmsg);
/*
diff --git a/net/socket.c b/net/socket.c
index cb0fdf7..b332d1e 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -652,6 +652,20 @@
}
EXPORT_SYMBOL(kernel_sendmsg);
+int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
+ struct kvec *vec, size_t num, size_t size)
+{
+ struct socket *sock = sk->sk_socket;
+
+ if (!sock->ops->sendmsg_locked)
+ sock_no_sendmsg_locked(sk, msg, size);
+
+ iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
+
+ return sock->ops->sendmsg_locked(sk, msg, msg_data_left(msg));
+}
+EXPORT_SYMBOL(kernel_sendmsg_locked);
+
static bool skb_is_err_queue(const struct sk_buff *skb)
{
/* pkt_type of skbs enqueued on the error queue are set to
@@ -3376,6 +3390,19 @@
}
EXPORT_SYMBOL(kernel_sendpage);
+int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
+ size_t size, int flags)
+{
+ struct socket *sock = sk->sk_socket;
+
+ if (sock->ops->sendpage_locked)
+ return sock->ops->sendpage_locked(sk, page, offset, size,
+ flags);
+
+ return sock_no_sendpage_locked(sk, page, offset, size, flags);
+}
+EXPORT_SYMBOL(kernel_sendpage_locked);
+
int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg)
{
mm_segment_t oldfs = get_fs();