[RFC v2 2/5] virtio/vsock: add support for virtio datagram

Jiang Wang
2021-09-14T05:55:35Z

This patch add support for virtio dgram for the driver.
Implemented related functions for tx and rx, enqueue
and dequeue. Send packets synchronously to give sender
indication when the virtqueue is full.
Refactored virtio_transport_send_pkt_work() a little bit but
no functions changes for it.

Support for the host/device side is in another
patch.

Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
---
include/net/af_vsock.h | 1 +
.../events/vsock_virtio_transport_common.h | 2 +
include/uapi/linux/virtio_vsock.h | 1 +
net/vmw_vsock/af_vsock.c | 12 +
net/vmw_vsock/virtio_transport.c | 344 +++++++++++++++---
net/vmw_vsock/virtio_transport_common.c | 181 ++++++++-
6 files changed, 467 insertions(+), 74 deletions(-)

diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index ab207677e0a8..58c46c694670 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -208,6 +208,7 @@ void vsock_remove_sock(struct vsock_sock *vsk);
void vsock_for_each_connected_socket(void (*fn)(struct sock *sk));
int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk);
bool vsock_find_cid(unsigned int cid);
+int vsock_bind_stream(struct vsock_sock *vsk, struct sockaddr_vm *addr);

/**** TAP ****/

diff --git a/include/trace/events/vsock_virtio_transport_common.h b/include/trace/events/vsock_virtio_transport_common.h
index d0b3f0ea9ba1..1d8647a6b476 100644
--- a/include/trace/events/vsock_virtio_transport_common.h
+++ b/include/trace/events/vsock_virtio_transport_common.h
@@ -10,10 +10,12 @@

TRACE_DEFINE_ENUM(VIRTIO_VSOCK_TYPE_STREAM);
TRACE_DEFINE_ENUM(VIRTIO_VSOCK_TYPE_SEQPACKET);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_TYPE_DGRAM);

#define show_type(val) \
__print_symbolic(val, \
{ VIRTIO_VSOCK_TYPE_STREAM, "STREAM" }, \
+ { VIRTIO_VSOCK_TYPE_DGRAM, "DGRAM" }, \
{ VIRTIO_VSOCK_TYPE_SEQPACKET, "SEQPACKET" })

TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_INVALID);
diff --git a/include/uapi/linux/virtio_vsock.h b/include/uapi/linux/virtio_vsock.h
index cff54ba9b924..3e93b75f2707 100644
--- a/include/uapi/linux/virtio_vsock.h
+++ b/include/uapi/linux/virtio_vsock.h
@@ -71,6 +71,7 @@ struct virtio_vsock_hdr {
enum virtio_vsock_type {
VIRTIO_VSOCK_TYPE_STREAM = 1,
VIRTIO_VSOCK_TYPE_SEQPACKET = 2,
+ VIRTIO_VSOCK_TYPE_DGRAM = 3,
};

enum virtio_vsock_op {
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 3e02cc3b24f8..adf11db32506 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -669,6 +669,18 @@ static int __vsock_bind_connectible(struct vsock_sock *vsk,
return 0;
}

+int vsock_bind_stream(struct vsock_sock *vsk,
+ struct sockaddr_vm *addr)
+{
+ int retval;
+
+ spin_lock_bh(&vsock_table_lock);
+ retval = __vsock_bind_connectible(vsk, addr);
+ spin_unlock_bh(&vsock_table_lock);
+ return retval;
+}
+EXPORT_SYMBOL(vsock_bind_stream);
+
static int __vsock_bind_dgram(struct vsock_sock *vsk,
struct sockaddr_vm *addr)
{
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index bb89f538f5f3..8d5bfcd79555 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -20,21 +20,29 @@
#include <net/sock.h>
#include <linux/mutex.h>
#include <net/af_vsock.h>
+#include<linux/kobject.h>
+#include<linux/sysfs.h>
+#include <linux/refcount.h>

static struct workqueue_struct *virtio_vsock_workqueue;
static struct virtio_vsock __rcu *the_virtio_vsock;
+static struct virtio_vsock *the_virtio_vsock_dgram;
static DEFINE_MUTEX(the_virtio_vsock_mutex); /* protects the_virtio_vsock */

struct virtio_vsock {
struct virtio_device *vdev;
struct virtqueue **vqs;
bool has_dgram;
+ refcount_t active;

/* Virtqueue processing is deferred to a workqueue */
struct work_struct tx_work;
struct work_struct rx_work;
struct work_struct event_work;

+ struct work_struct dgram_tx_work;
+ struct work_struct dgram_rx_work;
+
/* The following fields are protected by tx_lock. vqs[VSOCK_VQ_TX]
* must be accessed with tx_lock held.
*/
@@ -55,6 +63,22 @@ struct virtio_vsock {
int rx_buf_nr;
int rx_buf_max_nr;

+ /* The following fields are protected by dgram_tx_lock. vqs[VSOCK_VQ_DGRAM_TX]
+ * must be accessed with dgram_tx_lock held.
+ */
+ struct mutex dgram_tx_lock;
+ bool dgram_tx_run;
+
+ atomic_t dgram_queued_replies;
+
+ /* The following fields are protected by dgram_rx_lock. vqs[VSOCK_VQ_DGRAM_RX]
+ * must be accessed with dgram_rx_lock held.
+ */
+ struct mutex dgram_rx_lock;
+ bool dgram_rx_run;
+ int dgram_rx_buf_nr;
+ int dgram_rx_buf_max_nr;
+
/* The following fields are protected by event_lock.
* vqs[VSOCK_VQ_EVENT] must be accessed with event_lock held.
*/
@@ -84,21 +108,12 @@ static u32 virtio_transport_get_local_cid(void)
return ret;
}

-static void
-virtio_transport_send_pkt_work(struct work_struct *work)
+static void virtio_transport_do_send_pkt(struct virtio_vsock *vsock,
+ struct virtqueue *vq, spinlock_t *lock,
+ struct list_head *send_pkt_list,
+ bool *restart_rx)
{
- struct virtio_vsock *vsock =
- container_of(work, struct virtio_vsock, send_pkt_work);
- struct virtqueue *vq;
bool added = false;
- bool restart_rx = false;
-
- mutex_lock(&vsock->tx_lock);
-
- if (!vsock->tx_run)
- goto out;
-
- vq = vsock->vqs[VSOCK_VQ_TX];

for (;;) {
struct virtio_vsock_pkt *pkt;
@@ -106,16 +121,16 @@ virtio_transport_send_pkt_work(struct work_struct *work)
int ret, in_sg = 0, out_sg = 0;
bool reply;

- spin_lock_bh(&vsock->send_pkt_list_lock);
- if (list_empty(&vsock->send_pkt_list)) {
- spin_unlock_bh(&vsock->send_pkt_list_lock);
+ spin_lock_bh(lock);
+ if (list_empty(send_pkt_list)) {
+ spin_unlock_bh(lock);
break;
}

- pkt = list_first_entry(&vsock->send_pkt_list,
+ pkt = list_first_entry(send_pkt_list,
struct virtio_vsock_pkt, list);
list_del_init(&pkt->list);
- spin_unlock_bh(&vsock->send_pkt_list_lock);
+ spin_unlock_bh(lock);

virtio_transport_deliver_tap_pkt(pkt);

@@ -133,9 +148,9 @@ virtio_transport_send_pkt_work(struct work_struct *work)
* the vq
*/
if (ret < 0) {
- spin_lock_bh(&vsock->send_pkt_list_lock);
- list_add(&pkt->list, &vsock->send_pkt_list);
- spin_unlock_bh(&vsock->send_pkt_list_lock);
+ spin_lock_bh(lock);
+ list_add(&pkt->list, send_pkt_list);
+ spin_unlock_bh(lock);
break;
}

@@ -147,7 +162,7 @@ virtio_transport_send_pkt_work(struct work_struct *work)

/* Do we now have resources to resume rx processing? */
if (val + 1 == virtqueue_get_vring_size(rx_vq))
- restart_rx = true;
+ *restart_rx = true;
}

added = true;
@@ -155,7 +170,55 @@ virtio_transport_send_pkt_work(struct work_struct *work)

if (added)
virtqueue_kick(vq);
+}
+
+static int virtio_transport_do_send_dgram_pkt(struct virtio_vsock *vsock,
+ struct virtqueue *vq,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct scatterlist hdr, buf, *sgs[2];
+ int ret, in_sg = 0, out_sg = 0;
+
+ virtio_transport_deliver_tap_pkt(pkt);
+
+ sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr));
+ sgs[out_sg++] = &hdr;
+ if (pkt->buf) {
+ sg_init_one(&buf, pkt->buf, pkt->len);
+ sgs[out_sg++] = &buf;
+ }
+
+ ret = virtqueue_add_sgs(vq, sgs, out_sg, in_sg, pkt, GFP_KERNEL);
+ /* Usually this means that there is no more space available in
+ * the vq
+ */
+ if (ret < 0) {
+ virtio_transport_free_pkt(pkt);
+ return -ENOMEM;
+ }
+
+ virtqueue_kick(vq);
+
+ return pkt->len;
+}
+
+static void
+virtio_transport_send_pkt_work(struct work_struct *work)
+{
+ struct virtio_vsock *vsock =
+ container_of(work, struct virtio_vsock, send_pkt_work);
+ struct virtqueue *vq;
+ bool restart_rx = false;

+ mutex_lock(&vsock->tx_lock);
+
+ if (!vsock->tx_run)
+ goto out;
+
+ vq = vsock->vqs[VSOCK_VQ_TX];
+
+ virtio_transport_do_send_pkt(vsock, vq, &vsock->send_pkt_list_lock,
+ &vsock->send_pkt_list, &restart_rx);
out:
mutex_unlock(&vsock->tx_lock);

@@ -163,12 +226,65 @@ virtio_transport_send_pkt_work(struct work_struct *work)
queue_work(virtio_vsock_workqueue, &vsock->rx_work);
}

+static int
+virtio_transport_send_dgram_pkt(struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_vsock *vsock;
+ int len = pkt->len;
+ struct virtqueue *vq;
+
+ vsock = the_virtio_vsock_dgram;
+
+ if (!vsock) {
+ virtio_transport_free_pkt(pkt);
+ return -ENODEV;
+ }
+
+ if (!vsock->dgram_tx_run) {
+ virtio_transport_free_pkt(pkt);
+ return -ENODEV;
+ }
+
+ if (!refcount_inc_not_zero(&vsock->active)) {
+ virtio_transport_free_pkt(pkt);
+ return -ENODEV;
+ }
+
+ if (le64_to_cpu(pkt->hdr.dst_cid) == vsock->guest_cid) {
+ virtio_transport_free_pkt(pkt);
+ len = -ENODEV;
+ goto out_ref;
+ }
+
+ /* send the pkt */
+ mutex_lock(&vsock->dgram_tx_lock);
+
+ if (!vsock->dgram_tx_run)
+ goto out_mutex;
+
+ vq = vsock->vqs[VSOCK_VQ_DGRAM_TX];
+
+ len = virtio_transport_do_send_dgram_pkt(vsock, vq, pkt);
+
+out_mutex:
+ mutex_unlock(&vsock->dgram_tx_lock);
+
+out_ref:
+ if (!refcount_dec_not_one(&vsock->active))
+ return -EFAULT;
+
+ return len;
+}
+
static int
virtio_transport_send_pkt(struct virtio_vsock_pkt *pkt)
{
struct virtio_vsock *vsock;
int len = pkt->len;

+ if (pkt->hdr.type == VIRTIO_VSOCK_TYPE_DGRAM)
+ return virtio_transport_send_dgram_pkt(pkt);
+
rcu_read_lock();
vsock = rcu_dereference(the_virtio_vsock);
if (!vsock) {
@@ -244,7 +360,7 @@ virtio_transport_cancel_pkt(struct vsock_sock *vsk)
return ret;
}

-static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
+static void virtio_vsock_rx_fill(struct virtio_vsock *vsock, bool is_dgram)
{
int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
struct virtio_vsock_pkt *pkt;
@@ -252,7 +368,10 @@ static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
struct virtqueue *vq;
int ret;

- vq = vsock->vqs[VSOCK_VQ_RX];
+ if (is_dgram)
+ vq = vsock->vqs[VSOCK_VQ_DGRAM_RX];
+ else
+ vq = vsock->vqs[VSOCK_VQ_RX];

do {
pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
@@ -278,26 +397,26 @@ static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
virtio_transport_free_pkt(pkt);
break;
}
- vsock->rx_buf_nr++;
+ if (is_dgram)
+ vsock->dgram_rx_buf_nr++;
+ else
+ vsock->rx_buf_nr++;
} while (vq->num_free);
- if (vsock->rx_buf_nr > vsock->rx_buf_max_nr)
- vsock->rx_buf_max_nr = vsock->rx_buf_nr;
+ if (is_dgram) {
+ if (vsock->dgram_rx_buf_nr > vsock->dgram_rx_buf_max_nr)
+ vsock->dgram_rx_buf_max_nr = vsock->dgram_rx_buf_nr;
+ } else {
+ if (vsock->rx_buf_nr > vsock->rx_buf_max_nr)
+ vsock->rx_buf_max_nr = vsock->rx_buf_nr;
+ }
+
virtqueue_kick(vq);
}

-static void virtio_transport_tx_work(struct work_struct *work)
+static bool virtio_transport_free_pkt_batch(struct virtqueue *vq)
{
- struct virtio_vsock *vsock =
- container_of(work, struct virtio_vsock, tx_work);
- struct virtqueue *vq;
bool added = false;

- vq = vsock->vqs[VSOCK_VQ_TX];
- mutex_lock(&vsock->tx_lock);
-
- if (!vsock->tx_run)
- goto out;
-
do {
struct virtio_vsock_pkt *pkt;
unsigned int len;
@@ -309,13 +428,43 @@ static void virtio_transport_tx_work(struct work_struct *work)
}
} while (!virtqueue_enable_cb(vq));

-out:
+ return added;
+}
+
+static void virtio_transport_tx_work(struct work_struct *work)
+{
+ struct virtio_vsock *vsock =
+ container_of(work, struct virtio_vsock, tx_work);
+ struct virtqueue *vq;
+ bool added = false;
+
+ vq = vsock->vqs[VSOCK_VQ_TX];
+ mutex_lock(&vsock->tx_lock);
+
+ if (vsock->tx_run)
+ added = virtio_transport_free_pkt_batch(vq);
+
mutex_unlock(&vsock->tx_lock);

if (added)
queue_work(virtio_vsock_workqueue, &vsock->send_pkt_work);
}

+static void virtio_transport_dgram_tx_work(struct work_struct *work)
+{
+ struct virtio_vsock *vsock =
+ container_of(work, struct virtio_vsock, dgram_tx_work);
+ struct virtqueue *vq;
+
+ vq = vsock->vqs[VSOCK_VQ_DGRAM_TX];
+ mutex_lock(&vsock->dgram_tx_lock);
+
+ if (vsock->dgram_tx_run)
+ virtio_transport_free_pkt_batch(vq);
+
+ mutex_unlock(&vsock->dgram_tx_lock);
+}
+
/* Is there space left for replies to rx packets? */
static bool virtio_transport_more_replies(struct virtio_vsock *vsock)
{
@@ -453,6 +602,11 @@ static void virtio_vsock_tx_done(struct virtqueue *vq)

static void virtio_vsock_dgram_tx_done(struct virtqueue *vq)
{
+ struct virtio_vsock *vsock = vq->vdev->priv;
+
+ if (!vsock)
+ return;
+ queue_work(virtio_vsock_workqueue, &vsock->dgram_tx_work);
}

static void virtio_vsock_rx_done(struct virtqueue *vq)
@@ -468,8 +622,12 @@ static bool virtio_transport_seqpacket_allow(u32 remote_cid);

static void virtio_vsock_dgram_rx_done(struct virtqueue *vq)
{
-}
+ struct virtio_vsock *vsock = vq->vdev->priv;

+ if (!vsock)
+ return;
+ queue_work(virtio_vsock_workqueue, &vsock->dgram_rx_work);
+}
static struct virtio_transport virtio_transport = {
.transport = {
.module = THIS_MODULE,
@@ -532,19 +690,9 @@ static bool virtio_transport_seqpacket_allow(u32 remote_cid)
return seqpacket_allow;
}

-static void virtio_transport_rx_work(struct work_struct *work)
+static void virtio_transport_do_rx_work(struct virtio_vsock *vsock,
+ struct virtqueue *vq, bool is_dgram)
{
- struct virtio_vsock *vsock =
- container_of(work, struct virtio_vsock, rx_work);
- struct virtqueue *vq;
-
- vq = vsock->vqs[VSOCK_VQ_RX];
-
- mutex_lock(&vsock->rx_lock);
-
- if (!vsock->rx_run)
- goto out;
-
do {
virtqueue_disable_cb(vq);
for (;;) {
@@ -564,7 +712,10 @@ static void virtio_transport_rx_work(struct work_struct *work)
break;
}

- vsock->rx_buf_nr--;
+ if (is_dgram)
+ vsock->dgram_rx_buf_nr--;
+ else
+ vsock->rx_buf_nr--;

/* Drop short/long packets */
if (unlikely(len < sizeof(pkt->hdr) ||
@@ -580,11 +731,45 @@ static void virtio_transport_rx_work(struct work_struct *work)
} while (!virtqueue_enable_cb(vq));

out:
+ return;
+}
+
+static void virtio_transport_rx_work(struct work_struct *work)
+{
+ struct virtio_vsock *vsock =
+ container_of(work, struct virtio_vsock, rx_work);
+ struct virtqueue *vq;
+
+ vq = vsock->vqs[VSOCK_VQ_RX];
+
+ mutex_lock(&vsock->rx_lock);
+
+ if (vsock->rx_run)
+ virtio_transport_do_rx_work(vsock, vq, false);
+
if (vsock->rx_buf_nr < vsock->rx_buf_max_nr / 2)
- virtio_vsock_rx_fill(vsock);
+ virtio_vsock_rx_fill(vsock, false);
mutex_unlock(&vsock->rx_lock);
}

+static void virtio_transport_dgram_rx_work(struct work_struct *work)
+{
+ struct virtio_vsock *vsock =
+ container_of(work, struct virtio_vsock, dgram_rx_work);
+ struct virtqueue *vq;
+
+ vq = vsock->vqs[VSOCK_VQ_DGRAM_RX];
+
+ mutex_lock(&vsock->dgram_rx_lock);
+
+ if (vsock->dgram_rx_run)
+ virtio_transport_do_rx_work(vsock, vq, true);
+
+ if (vsock->dgram_rx_buf_nr < vsock->dgram_rx_buf_max_nr / 2)
+ virtio_vsock_rx_fill(vsock, true);
+ mutex_unlock(&vsock->dgram_rx_lock);
+}
+
static int virtio_vsock_probe(struct virtio_device *vdev)
{
vq_callback_t *callbacks[] = {
@@ -592,7 +777,7 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
virtio_vsock_tx_done,
virtio_vsock_event_done,
};
- vq_callback_t *ex_callbacks[] = {
+ vq_callback_t *dgram_callbacks[] = {
virtio_vsock_rx_done,
virtio_vsock_tx_done,
virtio_vsock_dgram_rx_done,
@@ -651,7 +836,7 @@ static int virtio_vsock_probe(struct virtio_device *vdev)

if (vsock->has_dgram) {
ret = virtio_find_vqs(vsock->vdev, max_vq,
- vsock->vqs, ex_callbacks, ex_names,
+ vsock->vqs, dgram_callbacks, ex_names,
NULL);
} else {
ret = virtio_find_vqs(vsock->vdev, max_vq,
@@ -668,8 +853,14 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
vsock->rx_buf_max_nr = 0;
atomic_set(&vsock->queued_replies, 0);

+ vsock->dgram_rx_buf_nr = 0;
+ vsock->dgram_rx_buf_max_nr = 0;
+ atomic_set(&vsock->dgram_queued_replies, 0);
+
mutex_init(&vsock->tx_lock);
mutex_init(&vsock->rx_lock);
+ mutex_init(&vsock->dgram_tx_lock);
+ mutex_init(&vsock->dgram_rx_lock);
mutex_init(&vsock->event_lock);
spin_lock_init(&vsock->send_pkt_list_lock);
INIT_LIST_HEAD(&vsock->send_pkt_list);
@@ -677,16 +868,27 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
INIT_WORK(&vsock->tx_work, virtio_transport_tx_work);
INIT_WORK(&vsock->event_work, virtio_transport_event_work);
INIT_WORK(&vsock->send_pkt_work, virtio_transport_send_pkt_work);
+ INIT_WORK(&vsock->dgram_rx_work, virtio_transport_dgram_rx_work);
+ INIT_WORK(&vsock->dgram_tx_work, virtio_transport_dgram_tx_work);

mutex_lock(&vsock->tx_lock);
vsock->tx_run = true;
mutex_unlock(&vsock->tx_lock);

+ mutex_lock(&vsock->dgram_tx_lock);
+ vsock->dgram_tx_run = true;
+ mutex_unlock(&vsock->dgram_tx_lock);
+
mutex_lock(&vsock->rx_lock);
- virtio_vsock_rx_fill(vsock);
+ virtio_vsock_rx_fill(vsock, false);
vsock->rx_run = true;
mutex_unlock(&vsock->rx_lock);

+ mutex_lock(&vsock->dgram_rx_lock);
+ virtio_vsock_rx_fill(vsock, true);
+ vsock->dgram_rx_run = true;
+ mutex_unlock(&vsock->dgram_rx_lock);
+
mutex_lock(&vsock->event_lock);
virtio_vsock_event_fill(vsock);
vsock->event_run = true;
@@ -698,6 +900,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
vdev->priv = vsock;
rcu_assign_pointer(the_virtio_vsock, vsock);

+ the_virtio_vsock_dgram = vsock;
+ refcount_set(&the_virtio_vsock_dgram->active, 1);
+
mutex_unlock(&the_virtio_vsock_mutex);

return 0;
@@ -729,14 +934,27 @@ static void virtio_vsock_remove(struct virtio_device *vdev)
vsock->rx_run = false;
mutex_unlock(&vsock->rx_lock);

+ mutex_lock(&vsock->dgram_rx_lock);
+ vsock->dgram_rx_run = false;
+ mutex_unlock(&vsock->dgram_rx_lock);
+
mutex_lock(&vsock->tx_lock);
vsock->tx_run = false;
mutex_unlock(&vsock->tx_lock);

+ mutex_lock(&vsock->dgram_tx_lock);
+ vsock->dgram_tx_run = false;
+ mutex_unlock(&vsock->dgram_tx_lock);
+
mutex_lock(&vsock->event_lock);
vsock->event_run = false;
mutex_unlock(&vsock->event_lock);

+ while (!refcount_dec_if_one(&the_virtio_vsock_dgram->active)) {
+ if (signal_pending(current))
+ break;
+ }
+
/* Flush all device writes and interrupts, device will not use any
* more buffers.
*/
@@ -747,11 +965,21 @@ static void virtio_vsock_remove(struct virtio_device *vdev)
virtio_transport_free_pkt(pkt);
mutex_unlock(&vsock->rx_lock);

+ mutex_lock(&vsock->dgram_rx_lock);
+ while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_DGRAM_RX])))
+ virtio_transport_free_pkt(pkt);
+ mutex_unlock(&vsock->dgram_rx_lock);
+
mutex_lock(&vsock->tx_lock);
while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_TX])))
virtio_transport_free_pkt(pkt);
mutex_unlock(&vsock->tx_lock);

+ mutex_lock(&vsock->dgram_tx_lock);
+ while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_DGRAM_TX])))
+ virtio_transport_free_pkt(pkt);
+ mutex_unlock(&vsock->dgram_tx_lock);
+
spin_lock_bh(&vsock->send_pkt_list_lock);
while (!list_empty(&vsock->send_pkt_list)) {
pkt = list_first_entry(&vsock->send_pkt_list,
@@ -769,6 +997,8 @@ static void virtio_vsock_remove(struct virtio_device *vdev)
*/
flush_work(&vsock->rx_work);
flush_work(&vsock->tx_work);
+ flush_work(&vsock->dgram_rx_work);
+ flush_work(&vsock->dgram_tx_work);
flush_work(&vsock->event_work);
flush_work(&vsock->send_pkt_work);

@@ -806,7 +1036,7 @@ static int __init virtio_vsock_init(void)
return -ENOMEM;

ret = vsock_core_register(&virtio_transport.transport,
- VSOCK_TRANSPORT_F_G2H);
+ VSOCK_TRANSPORT_F_G2H | VSOCK_TRANSPORT_F_DGRAM);
if (ret)
goto out_wq;

diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 081e7ae93cb1..034de35fe7c8 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -26,6 +26,8 @@
/* Threshold for detecting small packets to copy */
#define GOOD_COPY_LEN 128

+static s64 virtio_transport_dgram_has_data(struct vsock_sock *vsk);
+
static const struct virtio_transport *
virtio_transport_get_ops(struct vsock_sock *vsk)
{
@@ -210,21 +212,28 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
vvs = vsk->trans;

/* we can send less than pkt_len bytes */
- if (pkt_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE)
- pkt_len = VIRTIO_VSOCK_MAX_PKT_BUF_SIZE;
+ if (pkt_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
+ if (info->type == VIRTIO_VSOCK_TYPE_STREAM)
+ pkt_len = VIRTIO_VSOCK_MAX_PKT_BUF_SIZE;
+ else
+ return 0;
+ }

- /* virtio_transport_get_credit might return less than pkt_len credit */
- pkt_len = virtio_transport_get_credit(vvs, pkt_len);
+ if (info->type == VIRTIO_VSOCK_TYPE_STREAM) {
+ /* virtio_transport_get_credit might return less than pkt_len credit */
+ pkt_len = virtio_transport_get_credit(vvs, pkt_len);

- /* Do not send zero length OP_RW pkt */
- if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
- return pkt_len;
+ /* Do not send zero length OP_RW pkt */
+ if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
+ return pkt_len;
+ }

pkt = virtio_transport_alloc_pkt(info, pkt_len,
src_cid, src_port,
dst_cid, dst_port);
if (!pkt) {
- virtio_transport_put_credit(vvs, pkt_len);
+ if (info->type == VIRTIO_VSOCK_TYPE_STREAM)
+ virtio_transport_put_credit(vvs, pkt_len);
return -ENOMEM;
}

@@ -474,6 +483,55 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk,
return dequeued_len;
}

+static ssize_t
+virtio_transport_dgram_do_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg, size_t len)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ struct virtio_vsock_pkt *pkt;
+ size_t total = 0;
+ int err = -EFAULT;
+
+ spin_lock_bh(&vvs->rx_lock);
+ if (total < len && !list_empty(&vvs->rx_queue)) {
+ pkt = list_first_entry(&vvs->rx_queue,
+ struct virtio_vsock_pkt, list);
+
+ total = len;
+ if (total > pkt->len - pkt->off)
+ total = pkt->len - pkt->off;
+ else if (total < pkt->len - pkt->off)
+ msg->msg_flags |= MSG_TRUNC;
+
+ /* sk_lock is held by caller so no one else can dequeue.
+ * Unlock rx_lock since memcpy_to_msg() may sleep.
+ */
+ spin_unlock_bh(&vvs->rx_lock);
+
+ err = memcpy_to_msg(msg, pkt->buf + pkt->off, total);
+ if (err)
+ return err;
+
+ spin_lock_bh(&vvs->rx_lock);
+
+ virtio_transport_dec_rx_pkt(vvs, pkt);
+ list_del(&pkt->list);
+ virtio_transport_free_pkt(pkt);
+ }
+
+ spin_unlock_bh(&vvs->rx_lock);
+
+ if (total > 0 && msg->msg_name) {
+ /* Provide the address of the sender. */
+ DECLARE_SOCKADDR(struct sockaddr_vm *, vm_addr, msg->msg_name);
+
+ vsock_addr_init(vm_addr, le64_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.src_port));
+ msg->msg_namelen = sizeof(*vm_addr);
+ }
+ return total;
+}
+
ssize_t
virtio_transport_stream_dequeue(struct vsock_sock *vsk,
struct msghdr *msg,
@@ -523,7 +581,66 @@ virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
struct msghdr *msg,
size_t len, int flags)
{
- return -EOPNOTSUPP;
+ struct sock *sk;
+ size_t err = 0;
+ long timeout;
+
+ DEFINE_WAIT(wait);
+
+ sk = &vsk->sk;
+ err = 0;
+
+ lock_sock(sk);
+
+ if (flags & MSG_OOB || flags & MSG_ERRQUEUE || flags & MSG_PEEK)
+ return -EOPNOTSUPP;
+
+ if (!len)
+ goto out;
+
+ timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+
+ while (1) {
+ s64 ready;
+
+ prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+ ready = virtio_transport_dgram_has_data(vsk);
+
+ if (ready == 0) {
+ if (timeout == 0) {
+ err = -EAGAIN;
+ finish_wait(sk_sleep(sk), &wait);
+ break;
+ }
+
+ release_sock(sk);
+ timeout = schedule_timeout(timeout);
+ lock_sock(sk);
+
+ if (signal_pending(current)) {
+ err = sock_intr_errno(timeout);
+ finish_wait(sk_sleep(sk), &wait);
+ break;
+ } else if (timeout == 0) {
+ err = -EAGAIN;
+ finish_wait(sk_sleep(sk), &wait);
+ break;
+ }
+ } else {
+ finish_wait(sk_sleep(sk), &wait);
+
+ if (ready < 0) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ err = virtio_transport_dgram_do_dequeue(vsk, msg, len);
+ break;
+ }
+ }
+out:
+ release_sock(sk);
+ return err;
}
EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue);

@@ -553,6 +670,11 @@ u32 virtio_transport_seqpacket_has_data(struct vsock_sock *vsk)
}
EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_has_data);

+static s64 virtio_transport_dgram_has_data(struct vsock_sock *vsk)
+{
+ return virtio_transport_stream_has_data(vsk);
+}
+
static s64 virtio_transport_has_space(struct vsock_sock *vsk)
{
struct virtio_vsock_sock *vvs = vsk->trans;
@@ -731,13 +853,15 @@ EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
int virtio_transport_dgram_bind(struct vsock_sock *vsk,
struct sockaddr_vm *addr)
{
- return -EOPNOTSUPP;
+ //use same stream bind for dgram
+ int ret = vsock_bind_stream(vsk, addr);
+ return ret;
}
EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);

bool virtio_transport_dgram_allow(u32 cid, u32 port)
{
- return false;
+ return true;
}
EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);

@@ -773,7 +897,17 @@ virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
struct msghdr *msg,
size_t dgram_len)
{
- return -EOPNOTSUPP;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RW,
+ .type = VIRTIO_VSOCK_TYPE_DGRAM,
+ .msg = msg,
+ .pkt_len = dgram_len,
+ .vsk = vsk,
+ .remote_cid = remote_addr->svm_cid,
+ .remote_port = remote_addr->svm_port,
+ };
+
+ return virtio_transport_send_pkt_info(vsk, &info);
}
EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue);

@@ -846,7 +980,6 @@ static int virtio_transport_reset_no_sock(const struct virtio_transport *t,
virtio_transport_free_pkt(reply);
return -ENOTCONN;
}
-
return t->send_pkt(reply);
}

@@ -1049,7 +1182,8 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk,
* of a new record.
*/
if ((pkt->len <= last_pkt->buf_len - last_pkt->len) &&
- !(le32_to_cpu(last_pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOR)) {
+ !(le32_to_cpu(last_pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOR) &&
+ (le32_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_DGRAM)) {
memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
pkt->len);
last_pkt->len += pkt->len;
@@ -1074,6 +1208,12 @@ virtio_transport_recv_connected(struct sock *sk,
struct vsock_sock *vsk = vsock_sk(sk);
int err = 0;

+ if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_DGRAM) {
+ virtio_transport_recv_enqueue(vsk, pkt);
+ sk->sk_data_ready(sk);
+ return err;
+ }
+
switch (le16_to_cpu(pkt->hdr.op)) {
case VIRTIO_VSOCK_OP_RW:
virtio_transport_recv_enqueue(vsk, pkt);
@@ -1226,7 +1366,8 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt,
static bool virtio_transport_valid_type(u16 type)
{
return (type == VIRTIO_VSOCK_TYPE_STREAM) ||
- (type == VIRTIO_VSOCK_TYPE_SEQPACKET);
+ (type == VIRTIO_VSOCK_TYPE_SEQPACKET) ||
+ (type == VIRTIO_VSOCK_TYPE_DGRAM);
}

/* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
@@ -1289,11 +1430,16 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
goto free_pkt;
}

- space_available = virtio_transport_space_update(sk, pkt);
-
/* Update CID in case it has changed after a transport reset event */
vsk->local_addr.svm_cid = dst.svm_cid;

+ if (sk->sk_type == SOCK_DGRAM) {
+ virtio_transport_recv_connected(sk, pkt);
+ goto out;
+ }
+
+ space_available = virtio_transport_space_update(sk, pkt);
+
if (space_available)
sk->sk_write_space(sk);

@@ -1319,6 +1465,7 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
break;
}

+out:
release_sock(sk);

/* Release refcnt obtained when we fetched this socket out of the
--
2.20.1