1 files changed, 115 insertions, 92 deletions

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 0f39e08ee580..78af7518f263 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -58,6 +58,7 @@
 #include "sunrpc.h"
 
 static void xs_close(struct rpc_xprt *xprt);
+static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
 		struct socket *sock);
 
@@ -427,9 +428,9 @@ xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 		offset += want;
 	}
 
-	want = xs_alloc_sparse_pages(buf,
-			min_t(size_t, count - offset, buf->page_len),
-			GFP_KERNEL);
+	want = xs_alloc_sparse_pages(
+		buf, min_t(size_t, count - offset, buf->page_len),
+		GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
 	if (seek < want) {
 		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 				xdr_buf_pagecount(buf),
@@ -763,12 +764,12 @@ xs_stream_start_connect(struct sock_xprt *transport)
 /**
  * xs_nospace - handle transmit was incomplete
  * @req: pointer to RPC request
+ * @transport: pointer to struct sock_xprt
  *
  */
-static int xs_nospace(struct rpc_rqst *req)
+static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport)
 {
-	struct rpc_xprt *xprt = req->rq_xprt;
-	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
+	struct rpc_xprt *xprt = &transport->xprt;
 	struct sock *sk = transport->inet;
 	int ret = -EAGAIN;
 
@@ -780,24 +781,44 @@ static int xs_nospace(struct rpc_rqst *req)
 	/* Don't race with disconnect */
 	if (xprt_connected(xprt)) {
 		/* wait for more buffer space */
+		set_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
+		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
 		sk->sk_write_pending++;
 		xprt_wait_for_buffer_space(xprt);
 	} else
 		ret = -ENOTCONN;
 
 	spin_unlock(&xprt->transport_lock);
+	return ret;
+}
 
-	/* Race breaker in case memory is freed before above code is called */
-	if (ret == -EAGAIN) {
-		struct socket_wq *wq;
+static int xs_sock_nospace(struct rpc_rqst *req)
+{
+	struct sock_xprt *transport =
+		container_of(req->rq_xprt, struct sock_xprt, xprt);
+	struct sock *sk = transport->inet;
+	int ret = -EAGAIN;
 
-		rcu_read_lock();
-		wq = rcu_dereference(sk->sk_wq);
-		set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
-		rcu_read_unlock();
+	lock_sock(sk);
+	if (!sock_writeable(sk))
+		ret = xs_nospace(req, transport);
+	release_sock(sk);
+	return ret;
+}
 
-		sk->sk_write_space(sk);
-	}
+static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
+{
+	struct sock_xprt *transport =
+		container_of(req->rq_xprt, struct sock_xprt, xprt);
+	struct sock *sk = transport->inet;
+	int ret = -EAGAIN;
+
+	if (vm_wait)
+		return -ENOBUFS;
+	lock_sock(sk);
+	if (!sk_stream_memory_free(sk))
+		ret = xs_nospace(req, transport);
+	release_sock(sk);
 	return ret;
 }
 
@@ -805,7 +826,8 @@ static void
 xs_stream_prepare_request(struct rpc_rqst *req)
 {
 	xdr_free_bvec(&req->rq_rcv_buf);
-	req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
+	req->rq_task->tk_status = xdr_alloc_bvec(
+		&req->rq_rcv_buf, GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
 }
 
 /*
@@ -851,6 +873,7 @@ static int xs_local_send_request(struct rpc_rqst *req)
 	struct msghdr msg = {
 		.msg_flags	= XS_SENDMSG_FLAGS,
 	};
+	bool vm_wait;
 	unsigned int sent;
 	int status;
 
@@ -863,15 +886,14 @@ static int xs_local_send_request(struct rpc_rqst *req)
 	xs_pktdump("packet data:",
 			req->rq_svec->iov_base, req->rq_svec->iov_len);
 
+	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
+
 	req->rq_xtime = ktime_get();
 	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
 				   transport->xmit.offset, rm, &sent);
 	dprintk("RPC:       %s(%u) = %d\n",
 			__func__, xdr->len - transport->xmit.offset, status);
 
-	if (status == -EAGAIN && sock_writeable(transport->inet))
-		status = -ENOBUFS;
-
 	if (likely(sent > 0) || status == 0) {
 		transport->xmit.offset += sent;
 		req->rq_bytes_sent = transport->xmit.offset;
@@ -881,13 +903,12 @@ static int xs_local_send_request(struct rpc_rqst *req)
 			return 0;
 		}
 		status = -EAGAIN;
+		vm_wait = false;
 	}
 
 	switch (status) {
-	case -ENOBUFS:
-		break;
 	case -EAGAIN:
-		status = xs_nospace(req);
+		status = xs_stream_nospace(req, vm_wait);
 		break;
 	default:
 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
@@ -963,7 +984,7 @@ process_status:
 		/* Should we call xs_close() here? */
 		break;
 	case -EAGAIN:
-		status = xs_nospace(req);
+		status = xs_sock_nospace(req);
 		break;
 	case -ENETUNREACH:
 	case -ENOBUFS:
@@ -1005,7 +1026,7 @@ static int xs_tcp_send_request(struct rpc_rqst *req)
 	struct msghdr msg = {
 		.msg_flags	= XS_SENDMSG_FLAGS,
 	};
-	bool vm_wait = false;
+	bool vm_wait;
 	unsigned int sent;
 	int status;
 
@@ -1025,12 +1046,17 @@ static int xs_tcp_send_request(struct rpc_rqst *req)
 	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
 		xs_tcp_set_socket_timeouts(xprt, transport->sock);
 
+	xs_set_srcport(transport, transport->sock);
+
 	/* Continue transmitting the packet/record. We must be careful
 	 * to cope with writespace callbacks arriving _after_ we have
 	 * called sendmsg(). */
 	req->rq_xtime = ktime_get();
 	tcp_sock_set_cork(transport->inet, true);
-	while (1) {
+
+	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
+
+	do {
 		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
 					   transport->xmit.offset, rm, &sent);
 
@@ -1051,31 +1077,10 @@ static int xs_tcp_send_request(struct rpc_rqst *req)
 
 		WARN_ON_ONCE(sent == 0 && status == 0);
 
-		if (status == -EAGAIN ) {
-			/*
-			 * Return EAGAIN if we're sure we're hitting the
-			 * socket send buffer limits.
-			 */
-			if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
-				break;
-			/*
-			 * Did we hit a memory allocation failure?
-			 */
-			if (sent == 0) {
-				status = -ENOBUFS;
-				if (vm_wait)
-					break;
-				/* Retry, knowing now that we're below the
-				 * socket send buffer limit
-				 */
-				vm_wait = true;
-			}
-			continue;
-		}
-		if (status < 0)
-			break;
-		vm_wait = false;
-	}
+		if (sent > 0)
+			vm_wait = false;
+
+	} while (status == 0);
 
 	switch (status) {
 	case -ENOTSOCK:
@@ -1083,7 +1088,7 @@ static int xs_tcp_send_request(struct rpc_rqst *req)
 		/* Should we call xs_close() here? */
 		break;
 	case -EAGAIN:
-		status = xs_nospace(req);
+		status = xs_stream_nospace(req, vm_wait);
 		break;
 	case -ECONNRESET:
 	case -ECONNREFUSED:
@@ -1124,6 +1129,7 @@ static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
 	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
 	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
 	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
+	clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
 }
 
 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
@@ -1470,7 +1476,6 @@ static void xs_tcp_state_change(struct sock *sk)
 
 static void xs_write_space(struct sock *sk)
 {
-	struct socket_wq *wq;
 	struct sock_xprt *transport;
 	struct rpc_xprt *xprt;
 
@@ -1481,15 +1486,10 @@ static void xs_write_space(struct sock *sk)
 	if (unlikely(!(xprt = xprt_from_sock(sk))))
 		return;
 	transport = container_of(xprt, struct sock_xprt, xprt);
-	rcu_read_lock();
-	wq = rcu_dereference(sk->sk_wq);
-	if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
-		goto out;
-
+	if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
+		return;
 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
 	sk->sk_write_pending--;
-out:
-	rcu_read_unlock();
 }
 
 /**
@@ -1638,7 +1638,7 @@ static int xs_get_srcport(struct sock_xprt *transport)
 	return port;
 }
 
-unsigned short get_srcport(struct rpc_xprt *xprt)
+static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
 {
 	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
 	unsigned short ret = 0;
@@ -1648,7 +1648,25 @@ unsigned short get_srcport(struct rpc_xprt *xprt)
 	mutex_unlock(&sock->recv_mutex);
 	return ret;
 }
-EXPORT_SYMBOL(get_srcport);
+
+static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
+{
+	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
+	union {
+		struct sockaddr sa;
+		struct sockaddr_storage st;
+	} saddr;
+	int ret = -ENOTCONN;
+
+	mutex_lock(&sock->recv_mutex);
+	if (sock->sock) {
+		ret = kernel_getsockname(sock->sock, &saddr.sa);
+		if (ret >= 0)
+			ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
+	}
+	mutex_unlock(&sock->recv_mutex);
+	return ret;
+}
 
 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
 {
@@ -1830,7 +1848,6 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,
 		sk->sk_user_data = xprt;
 		sk->sk_data_ready = xs_data_ready;
 		sk->sk_write_space = xs_udp_write_space;
-		sock_set_flag(sk, SOCK_FASYNC);
 		sk->sk_error_report = xs_error_report;
 
 		xprt_clear_connected(xprt);
@@ -1936,9 +1953,9 @@ static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
 
 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
 /*
- * Note that this should be called with XPRT_LOCKED held (or when we otherwise
- * know that we have exclusive access to the socket), to guard against
- * races with xs_reset_transport.
+ * Note that this should be called with XPRT_LOCKED held, or recv_mutex
+ * held, or when we otherwise know that we have exclusive access to the
+ * socket, to guard against races with xs_reset_transport.
  */
 static void xs_set_memalloc(struct rpc_xprt *xprt)
 {
@@ -1967,13 +1984,11 @@ xs_enable_swap(struct rpc_xprt *xprt)
 {
 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
 
-	if (atomic_inc_return(&xprt->swapper) != 1)
-		return 0;
-	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
-		return -ERESTARTSYS;
-	if (xs->inet)
+	mutex_lock(&xs->recv_mutex);
+	if (atomic_inc_return(&xprt->swapper) == 1 &&
+	    xs->inet)
 		sk_set_memalloc(xs->inet);
-	xprt_release_xprt(xprt, NULL);
+	mutex_unlock(&xs->recv_mutex);
 	return 0;
 }
 
@@ -1989,13 +2004,11 @@ xs_disable_swap(struct rpc_xprt *xprt)
 {
 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
 
-	if (!atomic_dec_and_test(&xprt->swapper))
-		return;
-	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
-		return;
-	if (xs->inet)
+	mutex_lock(&xs->recv_mutex);
+	if (atomic_dec_and_test(&xprt->swapper) &&
+	    xs->inet)
 		sk_clear_memalloc(xs->inet);
-	xprt_release_xprt(xprt, NULL);
+	mutex_unlock(&xs->recv_mutex);
 }
 #else
 static void xs_set_memalloc(struct rpc_xprt *xprt)
@@ -2028,7 +2041,6 @@ static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
 		sk->sk_user_data = xprt;
 		sk->sk_data_ready = xs_data_ready;
 		sk->sk_write_space = xs_udp_write_space;
-		sock_set_flag(sk, SOCK_FASYNC);
 
 		xprt_set_connected(xprt);
 
@@ -2052,7 +2064,10 @@ static void xs_udp_setup_socket(struct work_struct *work)
 	struct rpc_xprt *xprt = &transport->xprt;
 	struct socket *sock;
 	int status = -EIO;
+	unsigned int pflags = current->flags;
 
+	if (atomic_read(&xprt->swapper))
+		current->flags |= PF_MEMALLOC;
 	sock = xs_create_sock(xprt, transport,
 			xs_addr(xprt)->sa_family, SOCK_DGRAM,
 			IPPROTO_UDP, false);
@@ -2072,6 +2087,7 @@ out:
 	xprt_clear_connecting(xprt);
 	xprt_unlock_connect(xprt, transport);
 	xprt_wake_pending_tasks(xprt, status);
+	current_restore_flags(pflags, PF_MEMALLOC);
 }
 
 /**
@@ -2191,7 +2207,6 @@ static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
 		sk->sk_data_ready = xs_data_ready;
 		sk->sk_state_change = xs_tcp_state_change;
 		sk->sk_write_space = xs_tcp_write_space;
-		sock_set_flag(sk, SOCK_FASYNC);
 		sk->sk_error_report = xs_error_report;
 
 		/* socket options */
@@ -2231,11 +2246,19 @@ static void xs_tcp_setup_socket(struct work_struct *work)
 	struct socket *sock = transport->sock;
 	struct rpc_xprt *xprt = &transport->xprt;
 	int status;
+	unsigned int pflags = current->flags;
 
-	if (!sock) {
-		sock = xs_create_sock(xprt, transport,
-				xs_addr(xprt)->sa_family, SOCK_STREAM,
-				IPPROTO_TCP, true);
+	if (atomic_read(&xprt->swapper))
+		current->flags |= PF_MEMALLOC;
+
+	if (xprt_connected(xprt))
+		goto out;
+	if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
+			       &transport->sock_state) ||
+	    !sock) {
+		xs_reset_transport(transport);
+		sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
+				      SOCK_STREAM, IPPROTO_TCP, true);
 		if (IS_ERR(sock)) {
 			xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
 			goto out;
@@ -2255,10 +2278,9 @@ static void xs_tcp_setup_socket(struct work_struct *work)
 			sock->sk->sk_state);
 	switch (status) {
 	case 0:
-		xs_set_srcport(transport, sock);
-		fallthrough;
 	case -EINPROGRESS:
 		/* SYN_SENT! */
+		set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
 		fallthrough;
@@ -2296,6 +2318,7 @@ out:
 	xprt_clear_connecting(xprt);
 out_unlock:
 	xprt_unlock_connect(xprt, transport);
+	current_restore_flags(pflags, PF_MEMALLOC);
 }
 
 /**
@@ -2319,13 +2342,9 @@ static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
 
 	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
 
-	if (transport->sock != NULL && !xprt_connecting(xprt)) {
+	if (transport->sock != NULL) {
 		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
-				"seconds\n",
-				xprt, xprt->reestablish_timeout / HZ);
-
-		/* Start by resetting any existing state */
-		xs_reset_transport(transport);
+			"seconds\n", xprt, xprt->reestablish_timeout / HZ);
 
 		delay = xprt_reconnect_delay(xprt);
 		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
@@ -2487,7 +2506,7 @@ static int bc_malloc(struct rpc_task *task)
 		return -EINVAL;
 	}
 
-	page = alloc_page(GFP_KERNEL);
+	page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
 	if (!page)
 		return -ENOMEM;
 
@@ -2621,6 +2640,8 @@ static const struct rpc_xprt_ops xs_udp_ops = {
 	.rpcbind		= rpcb_getport_async,
 	.set_port		= xs_set_port,
 	.connect		= xs_connect,
+	.get_srcaddr		= xs_sock_srcaddr,
+	.get_srcport		= xs_sock_srcport,
 	.buf_alloc		= rpc_malloc,
 	.buf_free		= rpc_free,
 	.send_request		= xs_udp_send_request,
@@ -2643,6 +2664,8 @@ static const struct rpc_xprt_ops xs_tcp_ops = {
 	.rpcbind		= rpcb_getport_async,
 	.set_port		= xs_set_port,
 	.connect		= xs_connect,
+	.get_srcaddr		= xs_sock_srcaddr,
+	.get_srcport		= xs_sock_srcport,
 	.buf_alloc		= rpc_malloc,
 	.buf_free		= rpc_free,
 	.prepare_request	= xs_stream_prepare_request,