--- /dev/null
+/*
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ * Copyright (c) 2009 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "net/queue.h"
+#include "qemu/queue.h"
+#include "net/net.h"
+
+/* The delivery handler may only return zero if it will call
+ * qemu_net_queue_flush() when it determines that it is once again able
+ * to deliver packets. It must also call qemu_net_queue_purge() in its
+ * cleanup path.
+ *
+ * If a sent callback is provided to send(), the caller must handle a
+ * zero return from the delivery handler by not sending any more packets
+ * until we have invoked the callback. Only in that case will we queue
+ * the packet.
+ *
+ * If a sent callback isn't provided, we just drop the packet to avoid
+ * unbounded queueing.
+ */
+
+struct NetPacket {
+ QTAILQ_ENTRY(NetPacket) entry;
+ NetClientState *sender;
+ unsigned flags;
+ int size;
+ NetPacketSent *sent_cb;
+ uint8_t data[0];
+};
+
+struct NetQueue {
+ void *opaque;
+ uint32_t nq_maxlen;
+ uint32_t nq_count;
+
+ QTAILQ_HEAD(packets, NetPacket) packets;
+
+ unsigned delivering : 1;
+};
+
+NetQueue *qemu_new_net_queue(void *opaque)
+{
+ NetQueue *queue;
+
+ queue = g_new0(NetQueue, 1);
+
+ queue->opaque = opaque;
+ queue->nq_maxlen = 10000;
+ queue->nq_count = 0;
+
+ QTAILQ_INIT(&queue->packets);
+
+ queue->delivering = 0;
+
+ return queue;
+}
+
+void qemu_del_net_queue(NetQueue *queue)
+{
+ NetPacket *packet, *next;
+
+ QTAILQ_FOREACH_SAFE(packet, &queue->packets, entry, next) {
+ QTAILQ_REMOVE(&queue->packets, packet, entry);
+ g_free(packet);
+ }
+
+ g_free(queue);
+}
+
+static void qemu_net_queue_append(NetQueue *queue,
+ NetClientState *sender,
+ unsigned flags,
+ const uint8_t *buf,
+ size_t size,
+ NetPacketSent *sent_cb)
+{
+ NetPacket *packet;
+
+ if (queue->nq_count >= queue->nq_maxlen && !sent_cb) {
+ return; /* drop if queue full and no callback */
+ }
+ packet = g_malloc(sizeof(NetPacket) + size);
+ packet->sender = sender;
+ packet->flags = flags;
+ packet->size = size;
+ packet->sent_cb = sent_cb;
+ memcpy(packet->data, buf, size);
+
+ queue->nq_count++;
+ QTAILQ_INSERT_TAIL(&queue->packets, packet, entry);
+}
+
+static void qemu_net_queue_append_iov(NetQueue *queue,
+ NetClientState *sender,
+ unsigned flags,
+ const struct iovec *iov,
+ int iovcnt,
+ NetPacketSent *sent_cb)
+{
+ NetPacket *packet;
+ size_t max_len = 0;
+ int i;
+
+ if (queue->nq_count >= queue->nq_maxlen && !sent_cb) {
+ return; /* drop if queue full and no callback */
+ }
+ for (i = 0; i < iovcnt; i++) {
+ max_len += iov[i].iov_len;
+ }
+
+ packet = g_malloc(sizeof(NetPacket) + max_len);
+ packet->sender = sender;
+ packet->sent_cb = sent_cb;
+ packet->flags = flags;
+ packet->size = 0;
+
+ for (i = 0; i < iovcnt; i++) {
+ size_t len = iov[i].iov_len;
+
+ memcpy(packet->data + packet->size, iov[i].iov_base, len);
+ packet->size += len;
+ }
+
+ queue->nq_count++;
+ QTAILQ_INSERT_TAIL(&queue->packets, packet, entry);
+}
+
+static ssize_t qemu_net_queue_deliver(NetQueue *queue,
+ NetClientState *sender,
+ unsigned flags,
+ const uint8_t *data,
+ size_t size)
+{
+ ssize_t ret = -1;
+
+ queue->delivering = 1;
+ ret = qemu_deliver_packet(sender, flags, data, size, queue->opaque);
+ queue->delivering = 0;
+
+ return ret;
+}
+
+static ssize_t qemu_net_queue_deliver_iov(NetQueue *queue,
+ NetClientState *sender,
+ unsigned flags,
+ const struct iovec *iov,
+ int iovcnt)
+{
+ ssize_t ret = -1;
+
+ queue->delivering = 1;
+ ret = qemu_deliver_packet_iov(sender, flags, iov, iovcnt, queue->opaque);
+ queue->delivering = 0;
+
+ return ret;
+}
+
+ssize_t qemu_net_queue_send(NetQueue *queue,
+ NetClientState *sender,
+ unsigned flags,
+ const uint8_t *data,
+ size_t size,
+ NetPacketSent *sent_cb)
+{
+ ssize_t ret;
+
+ if (queue->delivering || !qemu_can_send_packet(sender)) {
+ qemu_net_queue_append(queue, sender, flags, data, size, sent_cb);
+ return 0;
+ }
+
+ ret = qemu_net_queue_deliver(queue, sender, flags, data, size);
+ if (ret == 0) {
+ qemu_net_queue_append(queue, sender, flags, data, size, sent_cb);
+ return 0;
+ }
+
+ qemu_net_queue_flush(queue);
+
+ return ret;
+}
+
+ssize_t qemu_net_queue_send_iov(NetQueue *queue,
+ NetClientState *sender,
+ unsigned flags,
+ const struct iovec *iov,
+ int iovcnt,
+ NetPacketSent *sent_cb)
+{
+ ssize_t ret;
+
+ if (queue->delivering || !qemu_can_send_packet(sender)) {
+ qemu_net_queue_append_iov(queue, sender, flags, iov, iovcnt, sent_cb);
+ return 0;
+ }
+
+ ret = qemu_net_queue_deliver_iov(queue, sender, flags, iov, iovcnt);
+ if (ret == 0) {
+ qemu_net_queue_append_iov(queue, sender, flags, iov, iovcnt, sent_cb);
+ return 0;
+ }
+
+ qemu_net_queue_flush(queue);
+
+ return ret;
+}
+
+void qemu_net_queue_purge(NetQueue *queue, NetClientState *from)
+{
+ NetPacket *packet, *next;
+
+ QTAILQ_FOREACH_SAFE(packet, &queue->packets, entry, next) {
+ if (packet->sender == from) {
+ QTAILQ_REMOVE(&queue->packets, packet, entry);
+ queue->nq_count--;
+ if (packet->sent_cb) {
+ packet->sent_cb(packet->sender, 0);
+ }
+ g_free(packet);
+ }
+ }
+}
+
+bool qemu_net_queue_flush(NetQueue *queue)
+{
+ while (!QTAILQ_EMPTY(&queue->packets)) {
+ NetPacket *packet;
+ int ret;
+
+ packet = QTAILQ_FIRST(&queue->packets);
+ QTAILQ_REMOVE(&queue->packets, packet, entry);
+ queue->nq_count--;
+
+ ret = qemu_net_queue_deliver(queue,
+ packet->sender,
+ packet->flags,
+ packet->data,
+ packet->size);
+ if (ret == 0) {
+ queue->nq_count++;
+ QTAILQ_INSERT_HEAD(&queue->packets, packet, entry);
+ return false;
+ }
+
+ if (packet->sent_cb) {
+ packet->sent_cb(packet->sender, ret);
+ }
+
+ g_free(packet);
+ }
+ return true;
+}
Code Review / kvmfornfv.git / blobdiff