From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60056) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZNGOq-0002t4-F1 for qemu-devel@nongnu.org; Thu, 06 Aug 2015 04:19:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZNGOn-000078-5c for qemu-devel@nongnu.org; Thu, 06 Aug 2015 04:19:40 -0400 Received: from [59.151.112.132] (port=64577 helo=heian.cn.fujitsu.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZNGOj-00005l-L4 for qemu-devel@nongnu.org; Thu, 06 Aug 2015 04:19:37 -0400 Message-ID: <55C3187C.2050503@cn.fujitsu.com> Date: Thu, 6 Aug 2015 16:19:08 +0800 From: Yang Hongyang MIME-Version: 1.0 References: <1438677044-13030-1-git-send-email-yanghy@cn.fujitsu.com> <1438677044-13030-10-git-send-email-yanghy@cn.fujitsu.com> <55C30AE6.8080909@redhat.com> In-Reply-To: <55C30AE6.8080909@redhat.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v4 09/11] netfilter: add a netbuffer filter List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Wang , qemu-devel@nongnu.org Cc: thuth@redhat.com, zhang.zhanghailiang@huawei.com, lizhijian@cn.fujitsu.com, eddie.dong@intel.com, mrhines@linux.vnet.ibm.com, stefanha@redhat.com On 08/06/2015 03:21 PM, Jason Wang wrote: > > > On 08/04/2015 04:30 PM, Yang Hongyang wrote: >> This filter is to buffer/release packets, this feature can be used >> when using MicroCheckpointing, or other Remus like VM FT solutions, you >> can also use it to simulate the network delay. >> It has an interval option, if supplied, this filter will release >> packets by interval. >> >> Usage: >> -netdev tap,id=bn0 >> -netfilter buffer,id=f0,netdev=bn0,chain=in,interval=1000 >> >> NOTE: >> the scale of interval is microsecond. >> >> Signed-off-by: Yang Hongyang >> --- >> v4: remove bh >> pass the packet to next filter instead of receiver >> v3: check packet's sender and sender->peer when flush it >> --- >> net/Makefile.objs | 1 + >> net/filter-buffer.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++ >> net/filter.c | 2 + >> net/filters.h | 17 ++++++++ >> qapi-schema.json | 18 +++++++- >> 5 files changed, 157 insertions(+), 1 deletion(-) >> create mode 100644 net/filter-buffer.c >> create mode 100644 net/filters.h >> >> diff --git a/net/Makefile.objs b/net/Makefile.objs >> index 914aec0..5fa2f97 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 0000000..fd467db >> --- /dev/null >> +++ b/net/filter-buffer.c >> @@ -0,0 +1,120 @@ >> +/* >> + * Copyright (c) 2015 FUJITSU LIMITED >> + * Author: Yang Hongyang >> + * >> + * 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 "filters.h" >> +#include "qemu-common.h" >> +#include "qemu/timer.h" >> +#include "qemu/iov.h" >> + >> +typedef struct FILTERBUFFERState { >> + NetFilterState nf; >> + NetQueue *incoming_queue; >> + int64_t interval; > > Can interval be negative? No. > If not please uint. And not sure you really > need a 64 bit integer, if not, please use uint32_t. Ok, will use uint32_t instead. > >> + QEMUTimer release_timer; >> +} FILTERBUFFERState; > > Filter buffer is not abbreviation. So better name it as FilterBufferState. Ok, thanks. > >> + >> +static void packet_send_completed(NetClientState *nc, ssize_t len) >> +{ >> + return; >> +} > > Why need a dummy sent cb? Need to work around with queue_append, if there's no sent_cb, queue_append will simply drop the packet...Even we provide a sent_cb param to receive_iov, this dummy might still be needed because sent_cb might be null. > >> + >> +static void filter_buffer_flush(NetFilterState *nf) >> +{ >> + FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf); >> + NetQueue *queue = s->incoming_queue; >> + NetPacket *packet; >> + >> + while (queue && !QTAILQ_EMPTY(&queue->packets)) { >> + packet = QTAILQ_FIRST(&queue->packets); >> + QTAILQ_REMOVE(&queue->packets, packet, entry); >> + queue->nq_count--; >> + >> + if (packet->sender && packet->sender->peer) { >> + qemu_netfilter_pass_to_next(nf, packet->sender, packet->flags, >> + packet->data, packet->size); >> + } >> + >> + /* >> + * now that we pass the packet to next filter, we don't care the >> + * reture value here, because the filter layer or other filter >> + * will take care of this packet >> + */ >> + g_free(packet); > > This seems wrong, since packet could be queued into incoming queue. > Doing this may cause use after free. The incoming queue will make a copy of packet data when queued a packet. So I think it's ok to free this packet here...because this packet is alloced by this filter when calling qemu_net_queue_append_iov. > >> + } >> +} >> + >> +static void filter_buffer_release_timer(void *opaque) >> +{ >> + FILTERBUFFERState *s = opaque; >> + filter_buffer_flush(&s->nf); >> + 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) >> +{ >> + FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf); >> + NetQueue *queue = s->incoming_queue; >> + >> + qemu_net_queue_append_iov(queue, sender, flags, iov, iovcnt, >> + packet_send_completed); >> + return iov_size(iov, iovcnt); > > So if interval is zero, packet will be blocked forever and memory will > be exhausted. Yes, but this supposed to be used by FT solutions, so it will be released periodically. Currently only used with interval makes sense. > >> +} >> + >> +static void filter_buffer_cleanup(NetFilterState *nf) >> +{ >> + FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf); >> + >> + if (s->interval) { >> + timer_del(&s->release_timer); >> + } >> + >> + /* flush packets */ >> + filter_buffer_flush(nf); >> + g_free(s->incoming_queue); >> + return; >> +} >> + >> +static NetFilterInfo net_filter_buffer_info = { >> + .type = NET_FILTER_OPTIONS_KIND_BUFFER, >> + .size = sizeof(FILTERBUFFERState), >> + .receive_iov = filter_buffer_receive_iov, >> + .cleanup = filter_buffer_cleanup, >> +}; >> + >> +int net_init_filter_buffer(const NetFilterOptions *opts, const char *name, >> + int chain, NetClientState *netdev, Error **errp) >> +{ >> + NetFilterState *nf; >> + FILTERBUFFERState *s; >> + const NetFilterBufferOptions *bufferopt; >> + >> + assert(opts->kind == NET_FILTER_OPTIONS_KIND_BUFFER); >> + bufferopt = opts->buffer; >> + >> + nf = qemu_new_net_filter(&net_filter_buffer_info, >> + netdev, "buffer", name, chain); >> + s = DO_UPCAST(FILTERBUFFERState, nf, nf); >> + s->incoming_queue = qemu_new_net_queue(nf); >> + s->interval = bufferopt->has_interval ? bufferopt->interval : 0; >> + if (s->interval) { >> + timer_init_us(&s->release_timer, QEMU_CLOCK_VIRTUAL, >> + filter_buffer_release_timer, s); >> + timer_mod(&s->release_timer, >> + qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + s->interval); >> + } >> + >> + return 0; >> +} >> diff --git a/net/filter.c b/net/filter.c >> index 166b851..02f3e76 100644 >> --- a/net/filter.c >> +++ b/net/filter.c >> @@ -19,6 +19,7 @@ >> #include "net/filter.h" >> #include "net/net.h" >> #include "net/queue.h" >> +#include "filters.h" >> >> static QTAILQ_HEAD(, NetFilterState) net_filters; >> >> @@ -179,6 +180,7 @@ typedef int (NetFilterInit)(const NetFilterOptions *opts, >> >> static >> NetFilterInit * const net_filter_init_fun[NET_FILTER_OPTIONS_KIND_MAX] = { >> + [NET_FILTER_OPTIONS_KIND_BUFFER] = net_init_filter_buffer, >> }; >> >> static int net_filter_init1(const NetFilter *netfilter, Error **errp) >> diff --git a/net/filters.h b/net/filters.h >> new file mode 100644 >> index 0000000..3b546db >> --- /dev/null >> +++ b/net/filters.h >> @@ -0,0 +1,17 @@ >> +/* >> + * Copyright (c) 2015 FUJITSU LIMITED >> + * >> + * This work is licensed under the terms of the GNU GPL, version 2 or >> + * later. See the COPYING file in the top-level directory. >> + */ >> + >> +#ifndef QEMU_NET_FILTERS_H >> +#define QEMU_NET_FILTERS_H >> + >> +#include "net/net.h" >> +#include "net/filter.h" >> + >> +int net_init_filter_buffer(const NetFilterOptions *opts, const char *name, >> + int chain, NetClientState *netdev, Error **errp); >> + >> +#endif /* QEMU_NET_FILTERS_H */ >> diff --git a/qapi-schema.json b/qapi-schema.json >> index 9d97c21..e51bb59 100644 >> --- a/qapi-schema.json >> +++ b/qapi-schema.json >> @@ -2584,6 +2584,21 @@ >> { 'command': 'netfilter_del', 'data': {'id': 'str'} } >> >> ## >> +# @NetFilterBufferOptions >> +# >> +# a netbuffer filter for network backend. >> +# >> +# @interval: #optional release packets by interval, if no interval supplied, >> +# will release packets when filter_buffer_release_all been called. >> +# scale: microsecond >> +# >> +# Since 2.5 >> +## >> +{ 'struct': 'NetFilterBufferOptions', >> + 'data': { >> + '*interval': 'int64' } } >> + >> +## >> # @NetFilterOptions >> # >> # A discriminated record of network filters. >> @@ -2592,7 +2607,8 @@ >> # >> ## >> { 'union': 'NetFilterOptions', >> - 'data': { } } >> + 'data': { >> + 'buffer': 'NetFilterBufferOptions'} } >> >> ## >> # @NetFilter > > . > -- Thanks, Yang.