--- /dev/null
+/*
+ * Copyright (c) 2015 FUJITSU LIMITED
+ * Author: Yang Hongyang <yanghy@cn.fujitsu.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "net/filter.h"
+#include "net/queue.h"
+#include "qapi/error.h"
+#include "qemu-common.h"
+#include "qemu/timer.h"
+#include "qemu/iov.h"
+#include "qapi/qmp/qerror.h"
+#include "qapi-visit.h"
+#include "qom/object.h"
+
+#define TYPE_FILTER_BUFFER "filter-buffer"
+
+#define FILTER_BUFFER(obj) \
+ OBJECT_CHECK(FilterBufferState, (obj), TYPE_FILTER_BUFFER)
+
+typedef struct FilterBufferState {
+ NetFilterState parent_obj;
+
+ NetQueue *incoming_queue;
+ uint32_t interval;
+ QEMUTimer release_timer;
+} FilterBufferState;
+
+static void filter_buffer_flush(NetFilterState *nf)
+{
+ FilterBufferState *s = FILTER_BUFFER(nf);
+
+ if (!qemu_net_queue_flush(s->incoming_queue)) {
+ /* Unable to empty the queue, purge remaining packets */
+ qemu_net_queue_purge(s->incoming_queue, nf->netdev);
+ }
+}
+
+static void filter_buffer_release_timer(void *opaque)
+{
+ NetFilterState *nf = opaque;
+ FilterBufferState *s = FILTER_BUFFER(nf);
+
+ /*
+ * Note: filter_buffer_flush() drops packets that can't be sent
+ * TODO: We should leave them queued. But currently there's no way
+ * for the next filter or receiver to notify us that it can receive
+ * more packets.
+ */
+ filter_buffer_flush(nf);
+ /* Timer rearmed to fire again in s->interval microseconds. */
+ timer_mod(&s->release_timer,
+ qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + s->interval);
+}
+
+/* filter APIs */
+static ssize_t filter_buffer_receive_iov(NetFilterState *nf,
+ NetClientState *sender,
+ unsigned flags,
+ const struct iovec *iov,
+ int iovcnt,
+ NetPacketSent *sent_cb)
+{
+ FilterBufferState *s = FILTER_BUFFER(nf);
+
+ /*
+ * We return size when buffer a packet, the sender will take it as
+ * a already sent packet, so sent_cb should not be called later.
+ *
+ * FIXME: Even if the guest can't receive packets for some reasons,
+ * the filter can still accept packets until its internal queue is full.
+ * For example:
+ * For some reason, receiver could not receive more packets
+ * (.can_receive() returns zero). Without a filter, at most one packet
+ * will be queued in incoming queue and sender's poll will be disabled
+ * unit its sent_cb() was called. With a filter, it will keep receiving
+ * the packets without caring about the receiver. This is suboptimal.
+ * May need more thoughts (e.g keeping sent_cb).
+ */
+ qemu_net_queue_append_iov(s->incoming_queue, sender, flags,
+ iov, iovcnt, NULL);
+ return iov_size(iov, iovcnt);
+}
+
+static void filter_buffer_cleanup(NetFilterState *nf)
+{
+ FilterBufferState *s = FILTER_BUFFER(nf);
+
+ if (s->interval) {
+ timer_del(&s->release_timer);
+ }
+
+ /* flush packets */
+ if (s->incoming_queue) {
+ filter_buffer_flush(nf);
+ g_free(s->incoming_queue);
+ }
+}
+
+static void filter_buffer_setup_timer(NetFilterState *nf)
+{
+ FilterBufferState *s = FILTER_BUFFER(nf);
+
+ if (s->interval) {
+ timer_init_us(&s->release_timer, QEMU_CLOCK_VIRTUAL,
+ filter_buffer_release_timer, nf);
+ /* Timer armed to fire in s->interval microseconds. */
+ timer_mod(&s->release_timer,
+ qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + s->interval);
+ }
+}
+
+static void filter_buffer_setup(NetFilterState *nf, Error **errp)
+{
+ FilterBufferState *s = FILTER_BUFFER(nf);
+
+ /*
+ * We may want to accept zero interval when VM FT solutions like MC
+ * or COLO use this filter to release packets on demand.
+ */
+ if (!s->interval) {
+ error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "interval",
+ "a non-zero interval");
+ return;
+ }
+
+ s->incoming_queue = qemu_new_net_queue(qemu_netfilter_pass_to_next, nf);
+ filter_buffer_setup_timer(nf);
+}
+
+static void filter_buffer_status_changed(NetFilterState *nf, Error **errp)
+{
+ FilterBufferState *s = FILTER_BUFFER(nf);
+
+ if (!nf->on) {
+ if (s->interval) {
+ timer_del(&s->release_timer);
+ }
+ filter_buffer_flush(nf);
+ } else {
+ filter_buffer_setup_timer(nf);
+ }
+}
+
+static void filter_buffer_class_init(ObjectClass *oc, void *data)
+{
+ NetFilterClass *nfc = NETFILTER_CLASS(oc);
+
+ nfc->setup = filter_buffer_setup;
+ nfc->cleanup = filter_buffer_cleanup;
+ nfc->receive_iov = filter_buffer_receive_iov;
+ nfc->status_changed = filter_buffer_status_changed;
+}
+
+static void filter_buffer_get_interval(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ FilterBufferState *s = FILTER_BUFFER(obj);
+ uint32_t value = s->interval;
+
+ visit_type_uint32(v, name, &value, errp);
+}
+
+static void filter_buffer_set_interval(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ FilterBufferState *s = FILTER_BUFFER(obj);
+ Error *local_err = NULL;
+ uint32_t value;
+
+ visit_type_uint32(v, name, &value, &local_err);
+ if (local_err) {
+ goto out;
+ }
+ if (!value) {
+ error_setg(&local_err, "Property '%s.%s' requires a positive value",
+ object_get_typename(obj), name);
+ goto out;
+ }
+ s->interval = value;
+
+out:
+ error_propagate(errp, local_err);
+}
+
+static void filter_buffer_init(Object *obj)
+{
+ object_property_add(obj, "interval", "int",
+ filter_buffer_get_interval,
+ filter_buffer_set_interval, NULL, NULL, NULL);
+}
+
+static const TypeInfo filter_buffer_info = {
+ .name = TYPE_FILTER_BUFFER,
+ .parent = TYPE_NETFILTER,
+ .class_init = filter_buffer_class_init,
+ .instance_init = filter_buffer_init,
+ .instance_size = sizeof(FilterBufferState),
+};
+
+static void register_types(void)
+{
+ type_register_static(&filter_buffer_info);
+}
+
+type_init(register_types);
Code Review / kvmfornfv.git / blobdiff