diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index 1c53c4c4d88fecc3e0b8e1632b9132f644fea403..568a87c5e0d0f95622bc153ecb9a39e803479ad7 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -78,6 +78,7 @@ struct vsock_sock {
s64 vsock_stream_has_data(struct vsock_sock *vsk);
s64 vsock_stream_has_space(struct vsock_sock *vsk);
struct sock *vsock_create_connected(struct sock *parent);
+void vsock_data_ready(struct sock *sk);
/**** TRANSPORT ****/
@@ -135,6 +136,7 @@ struct vsock_transport {
u64 (*stream_rcvhiwat)(struct vsock_sock *);
bool (*stream_is_active)(struct vsock_sock *);
bool (*stream_allow)(u32 cid, u32 port);
+ int (*set_rcvlowat)(struct vsock_sock *vsk, int val);
/* SEQ_PACKET. */
ssize_t (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg,
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index b4ee163154a683ef22568c6c05825fa2ad14a768..ee418701cdee902ee7fea08767f51be055b87ad6 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -882,6 +882,16 @@ s64 vsock_stream_has_space(struct vsock_sock *vsk)
}
EXPORT_SYMBOL_GPL(vsock_stream_has_space);
+void vsock_data_ready(struct sock *sk)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+
+ if (vsock_stream_has_data(vsk) >= sk->sk_rcvlowat ||
+ sock_flag(sk, SOCK_DONE))
+ sk->sk_data_ready(sk);
+}
+EXPORT_SYMBOL_GPL(vsock_data_ready);
+
static int vsock_release(struct socket *sock)
{
__vsock_release(sock->sk, 0);
@@ -1066,8 +1076,9 @@ static __poll_t vsock_poll(struct file *file, struct socket *sock,
if (transport && transport->stream_is_active(vsk) &&
!(sk->sk_shutdown & RCV_SHUTDOWN)) {
bool data_ready_now = false;
+ int target = sock_rcvlowat(sk, 0, INT_MAX);
int ret = transport->notify_poll_in(
- vsk, 1, &data_ready_now);
+ vsk, target, &data_ready_now);
if (ret < 0) {
mask |= EPOLLERR;
} else {
@@ -2137,6 +2148,25 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
return err;
}
+static int vsock_set_rcvlowat(struct sock *sk, int val)
+{
+ const struct vsock_transport *transport;
+ struct vsock_sock *vsk;
+
+ vsk = vsock_sk(sk);
+
+ if (val > vsk->buffer_size)
+ return -EINVAL;
+
+ transport = vsk->transport;
+
+ if (transport && transport->set_rcvlowat)
+ return transport->set_rcvlowat(vsk, val);
+
+ WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
+ return 0;
+}
+
static const struct proto_ops vsock_stream_ops = {
.family = PF_VSOCK,
.owner = THIS_MODULE,
@@ -2156,6 +2186,7 @@ static const struct proto_ops vsock_stream_ops = {
.recvmsg = vsock_connectible_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
+ .set_rcvlowat = vsock_set_rcvlowat,
};
static const struct proto_ops vsock_seqpacket_ops = {
diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
index fd98229e3db30988b983761b9c809ce059d6d9b2..59c3e2697069045ae1227f0ea1d1064823148517 100644
--- a/net/vmw_vsock/hyperv_transport.c
+++ b/net/vmw_vsock/hyperv_transport.c
@@ -815,6 +815,12 @@ int hvs_notify_send_post_enqueue(struct vsock_sock *vsk, ssize_t written,
return 0;
}
+static
+int hvs_set_rcvlowat(struct vsock_sock *vsk, int val)
+{
+ return -EOPNOTSUPP;
+}
+
static struct vsock_transport hvs_transport = {
.module = THIS_MODULE,
@@ -850,6 +856,7 @@ static struct vsock_transport hvs_transport = {
.notify_send_pre_enqueue = hvs_notify_send_pre_enqueue,
.notify_send_post_enqueue = hvs_notify_send_post_enqueue,
+ .set_rcvlowat = hvs_set_rcvlowat
};
static bool hvs_check_transport(struct vsock_sock *vsk)
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index ec2c2afbf0d060b4f6335a7616c8deba0a95fde6..35863132f4f117d3e2435cd3e9c9510814844b79 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -634,10 +634,7 @@ virtio_transport_notify_poll_in(struct vsock_sock *vsk,
size_t target,
bool *data_ready_now)
{
- if (vsock_stream_has_data(vsk))
- *data_ready_now = true;
- else
- *data_ready_now = false;
+ *data_ready_now = vsock_stream_has_data(vsk) >= target;
return 0;
}
@@ -1084,7 +1081,7 @@ virtio_transport_recv_connected(struct sock *sk,
switch (le16_to_cpu(pkt->hdr.op)) {
case VIRTIO_VSOCK_OP_RW:
virtio_transport_recv_enqueue(vsk, pkt);
- sk->sk_data_ready(sk);
+ vsock_data_ready(sk);
return err;
case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
virtio_transport_send_credit_update(vsk);
diff --git a/net/vmw_vsock/vmci_transport_notify.c b/net/vmw_vsock/vmci_transport_notify.c
index d69fc4b595ad42b2784698ea1e8e2b7b60632343..7c3a7db134b2820033c5d475731b0ab2b84382e5 100644
--- a/net/vmw_vsock/vmci_transport_notify.c
+++ b/net/vmw_vsock/vmci_transport_notify.c
@@ -307,7 +307,7 @@ vmci_transport_handle_wrote(struct sock *sk,
struct vsock_sock *vsk = vsock_sk(sk);
PKT_FIELD(vsk, sent_waiting_read) = false;
#endif
- sk->sk_data_ready(sk);
+ vsock_data_ready(sk);
}
static void vmci_transport_notify_pkt_socket_init(struct sock *sk)
@@ -340,12 +340,12 @@ vmci_transport_notify_pkt_poll_in(struct sock *sk,
{
struct vsock_sock *vsk = vsock_sk(sk);
- if (vsock_stream_has_data(vsk)) {
+ if (vsock_stream_has_data(vsk) >= target) {
*data_ready_now = true;
} else {
- /* We can't read right now because there is nothing in the
- * queue. Ask for notifications when there is something to
- * read.
+ /* We can't read right now because there is not enough data
+ * in the queue. Ask for notifications when there is something
+ * to read.
*/
if (sk->sk_state == TCP_ESTABLISHED) {
if (!send_waiting_read(sk, 1))
diff --git a/net/vmw_vsock/vmci_transport_notify_qstate.c b/net/vmw_vsock/vmci_transport_notify_qstate.c
index 0f36d7c45db3933f25add3a3e15f6f5fb8c242f7..e96a88d850a86a9ffbd422674b080ef324dc4799 100644
--- a/net/vmw_vsock/vmci_transport_notify_qstate.c
+++ b/net/vmw_vsock/vmci_transport_notify_qstate.c
@@ -84,7 +84,7 @@ vmci_transport_handle_wrote(struct sock *sk,
bool bottom_half,
struct sockaddr_vm *dst, struct sockaddr_vm *src)
{
- sk->sk_data_ready(sk);
+ vsock_data_ready(sk);
}
static void vsock_block_update_write_window(struct sock *sk)
@@ -161,12 +161,12 @@ vmci_transport_notify_pkt_poll_in(struct sock *sk,
{
struct vsock_sock *vsk = vsock_sk(sk);
- if (vsock_stream_has_data(vsk)) {
+ if (vsock_stream_has_data(vsk) >= target) {
*data_ready_now = true;
} else {
- /* We can't read right now because there is nothing in the
- * queue. Ask for notifications when there is something to
- * read.
+ /* We can't read right now because there is not enough data
+ * in the queue. Ask for notifications when there is something
+ * to read.
*/
if (sk->sk_state == TCP_ESTABLISHED)
vsock_block_update_write_window(sk);
@@ -282,7 +282,7 @@ vmci_transport_notify_pkt_recv_post_dequeue(
/* See the comment in
* vmci_transport_notify_pkt_send_post_enqueue().
*/
- sk->sk_data_ready(sk);
+ vsock_data_ready(sk);
}
return err;
diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c
index dc577461afc20546e44f700ddd49b83b78ececb4..bb6d691cb30d0d2fccdd1ea53c824f83ebde11c7 100644
--- a/tools/testing/vsock/vsock_test.c
+++ b/tools/testing/vsock/vsock_test.c
@@ -18,6 +18,7 @@
#include <sys/socket.h>
#include <time.h>
#include <sys/mman.h>
+#include <poll.h>
#include "timeout.h"
#include "control.h"
@@ -596,6 +597,108 @@ static void test_seqpacket_invalid_rec_buffer_server(const struct test_opts *opt
close(fd);
}
+#define RCVLOWAT_BUF_SIZE 128
+
+static void test_stream_poll_rcvlowat_server(const struct test_opts *opts)
+{
+ int fd;
+ int i;
+
+ fd = vsock_stream_accept(VMADDR_CID_ANY, 1234, NULL);
+ if (fd < 0) {
+ perror("accept");
+ exit(EXIT_FAILURE);
+ }
+
+ /* Send 1 byte. */
+ send_byte(fd, 1, 0);
+
+ control_writeln("SRVSENT");
+
+ /* Wait until client is ready to receive rest of data. */
+ control_expectln("CLNSENT");
+
+ for (i = 0; i < RCVLOWAT_BUF_SIZE - 1; i++)
+ send_byte(fd, 1, 0);
+
+ /* Keep socket in active state. */
+ control_expectln("POLLDONE");
+
+ close(fd);
+}
+
+static void test_stream_poll_rcvlowat_client(const struct test_opts *opts)
+{
+ unsigned long lowat_val = RCVLOWAT_BUF_SIZE;
+ char buf[RCVLOWAT_BUF_SIZE];
+ struct pollfd fds;
+ ssize_t read_res;
+ short poll_flags;
+ int fd;
+
+ fd = vsock_stream_connect(opts->peer_cid, 1234);
+ if (fd < 0) {
+ perror("connect");
+ exit(EXIT_FAILURE);
+ }
+
+ if (setsockopt(fd, SOL_SOCKET, SO_RCVLOWAT,
+ &lowat_val, sizeof(lowat_val))) {
+ perror("setsockopt");
+ exit(EXIT_FAILURE);
+ }
+
+ control_expectln("SRVSENT");
+
+ /* At this point, server sent 1 byte. */
+ fds.fd = fd;
+ poll_flags = POLLIN | POLLRDNORM;
+ fds.events = poll_flags;
+
+ /* Try to wait for 1 sec. */
+ if (poll(&fds, 1, 1000) < 0) {
+ perror("poll");
+ exit(EXIT_FAILURE);
+ }
+
+ /* poll() must return nothing. */
+ if (fds.revents) {
+ fprintf(stderr, "Unexpected poll result %hx\n",
+ fds.revents);
+ exit(EXIT_FAILURE);
+ }
+
+ /* Tell server to send rest of data. */
+ control_writeln("CLNSENT");
+
+ /* Poll for data. */
+ if (poll(&fds, 1, 10000) < 0) {
+ perror("poll");
+ exit(EXIT_FAILURE);
+ }
+
+ /* Only these two bits are expected. */
+ if (fds.revents != poll_flags) {
+ fprintf(stderr, "Unexpected poll result %hx\n",
+ fds.revents);
+ exit(EXIT_FAILURE);
+ }
+
+ /* Use MSG_DONTWAIT, if call is going to wait, EAGAIN
+ * will be returned.
+ */
+ read_res = recv(fd, buf, sizeof(buf), MSG_DONTWAIT);
+ if (read_res != RCVLOWAT_BUF_SIZE) {
+ fprintf(stderr, "Unexpected recv result %zi\n",
+ read_res);
+ exit(EXIT_FAILURE);
+ }
+
+ control_writeln("POLLDONE");
+
+ close(fd);
+}
+
static struct test_case test_cases[] = {
{
.name = "SOCK_STREAM connection reset",
@@ -646,6 +749,11 @@ static struct test_case test_cases[] = {
.run_client = test_seqpacket_invalid_rec_buffer_client,
.run_server = test_seqpacket_invalid_rec_buffer_server,
},
+ {
+ .name = "SOCK_STREAM poll() + SO_RCVLOWAT",
+ .run_client = test_stream_poll_rcvlowat_client,
+ .run_server = test_stream_poll_rcvlowat_server,
+ },
{},
};