diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/Makefile.objs | 1 | ||||
| -rw-r--r-- | net/filter-buffer.c | 186 |
2 files changed, 187 insertions, 0 deletions
diff --git a/net/Makefile.objs b/net/Makefile.objs index 914aec00a4..5fa2f9731d 100644 --- a/net/Makefile.objs +++ b/net/Makefile.objs @@ -14,3 +14,4 @@ common-obj-$(CONFIG_SLIRP) += slirp.o common-obj-$(CONFIG_VDE) += vde.o common-obj-$(CONFIG_NETMAP) += netmap.o common-obj-y += filter.o +common-obj-y += filter-buffer.o diff --git a/net/filter-buffer.c b/net/filter-buffer.c new file mode 100644 index 0000000000..57be149413 --- /dev/null +++ b/net/filter-buffer.c @@ -0,0 +1,186 @@ +/* + * 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 "net/filter.h" +#include "net/queue.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(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); + 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_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; +} + +static void filter_buffer_get_interval(Object *obj, Visitor *v, void *opaque, + const char *name, Error **errp) +{ + FilterBufferState *s = FILTER_BUFFER(obj); + uint32_t value = s->interval; + + visit_type_uint32(v, &value, name, errp); +} + +static void filter_buffer_set_interval(Object *obj, Visitor *v, void *opaque, + const char *name, Error **errp) +{ + FilterBufferState *s = FILTER_BUFFER(obj); + Error *local_err = NULL; + uint32_t value; + + visit_type_uint32(v, &value, name, &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); |