Re: [Qemu-devel] [RFC PATCH 3/9] colo-proxy: add colo-proxy framework

[Wen Congyang]

On 11/27/2015 08:27 PM, Zhang Chen wrote:
> From: zhangchen <address@hidden>
> 
> Colo-proxy is a plugin of qemu netfilter
> like filter-buffer and dump
> 
> Signed-off-by: zhangchen <address@hidden>
> ---
>  net/Makefile.objs |   1 +
>  net/colo-proxy.c  | 139 
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  net/colo-proxy.h  |  63 +++++++++++++++++++++++++
>  3 files changed, 203 insertions(+)
>  create mode 100644 net/colo-proxy.c
>  create mode 100644 net/colo-proxy.h
> 
> diff --git a/net/Makefile.objs b/net/Makefile.objs
> index 5fa2f97..95670f2 100644
> --- a/net/Makefile.objs
> +++ b/net/Makefile.objs
> @@ -15,3 +15,4 @@ common-obj-$(CONFIG_VDE) += vde.o
>  common-obj-$(CONFIG_NETMAP) += netmap.o
>  common-obj-y += filter.o
>  common-obj-y += filter-buffer.o
> +common-obj-y += colo-proxy.o
> diff --git a/net/colo-proxy.c b/net/colo-proxy.c
> new file mode 100644
> index 0000000..98c2699
> --- /dev/null
> +++ b/net/colo-proxy.c
> @@ -0,0 +1,139 @@
> +/*
> + * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
> + * (a.k.a. Fault Tolerance or Continuous Replication)
> + *
> + * Copyright (c) 2015 HUAWEI TECHNOLOGIES CO., LTD.
> + * Copyright (c) 2015 FUJITSU LIMITED
> + * Copyright (c) 2015 Intel Corporation
> + *
> + * Author: Zhang Chen <address@hidden>
> + *
> + * 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 "colo-proxy.h"
> +
> +#define __DEBUG__
> +
> +#ifdef __DEBUG__
> +#define DEBUG(format, ...) printf(format, ##__VA_ARGS__)
> +#else
> +#define DEBUG(format, ...)
> +#endif
> +
> +
> +static ssize_t colo_proxy_receive_iov(NetFilterState *nf,
> +                                         NetClientState *sender,
> +                                         unsigned flags,
> +                                         const struct iovec *iov,
> +                                         int iovcnt,
> +                                         NetPacketSent *sent_cb)
> +{
> +    /*
> +     * 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.
> +     *
> +     */
> +    ColoProxyState *s = FILTER_COLO_PROXY(nf);
> +    if (s->colo_mode == COLO_PRIMARY_MODE) {
> +         /* colo_proxy_primary_handler */
> +    } else {
> +         /* colo_proxy_primary_handler */
> +    }
> +    return iov_size(iov, iovcnt);
> +}
> +
> +static void colo_proxy_cleanup(NetFilterState *nf)
> +{
> +     /* cleanup */
> +}
> +
> +
> +static void colo_proxy_setup(NetFilterState *nf, Error **errp)
> +{
> +    ColoProxyState *s = FILTER_COLO_PROXY(nf);
> +    if (!s->addr) {
> +        error_setg(errp, "filter colo_proxy needs 'addr' \
> +                     property set!");
> +        return;
> +    }
> +
> +    if (nf->direction != NET_FILTER_DIRECTION_ALL) {
> +        printf("colo need queue all packet,\

s/need/needs/

> +                    please startup colo-proxy with queue=all\n");
> +        return;
> +    }
> +
> +    s->sockfd = -1;
> +    s->has_failover = false;
> +    colo_do_checkpoint = false;
> +    g_queue_init(&s->unprocessed_connections);
> +
> +    if (!strcmp(mode, PRIMARY_MODE)) {
> +        s->colo_mode = COLO_PRIMARY_MODE;
> +    } else if (!strcmp(mode, SECONDARY_MODE)) {
> +        s->colo_mode = COLO_SECONDARY_MODE;
> +    } else {
> +        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "mode",
> +                    "primary or secondary");
> +        return;
> +    }
> +}
> +
> +static void colo_proxy_class_init(ObjectClass *oc, void *data)
> +{
> +    NetFilterClass *nfc = NETFILTER_CLASS(oc);
> +
> +    nfc->setup = colo_proxy_setup;
> +    nfc->cleanup = colo_proxy_cleanup;
> +    nfc->receive_iov = colo_proxy_receive_iov;
> +}
> +
> +static char *colo_proxy_get_mode(Object *obj, Error **errp)
> +{
> +    return g_strdup(mode);
> +}
> +
> +static void colo_proxy_set_mode(Object *obj, const char *value, Error **errp)
> +{
> +    g_free(mode);
> +    mode = g_strdup(value);
> +}
> +
> +static char *colo_proxy_get_addr(Object *obj, Error **errp)
> +{
> +    ColoProxyState *s = FILTER_COLO_PROXY(obj);
> +
> +    return g_strdup(s->addr);
> +}
> +
> +static void colo_proxy_set_addr(Object *obj, const char *value, Error **errp)
> +{
> +    ColoProxyState *s = FILTER_COLO_PROXY(obj);
> +    g_free(s->addr);
> +    s->addr = g_strdup(value);

You can parse the address here, and can find the format error as early as 
possible.

> +}
> +
> +static void colo_proxy_init(Object *obj)
> +{
> +    object_property_add_str(obj, "mode", colo_proxy_get_mode,
> +                            colo_proxy_set_mode, NULL);
> +    object_property_add_str(obj, "addr", colo_proxy_get_addr,
> +                            colo_proxy_set_addr, NULL);
> +}
> +
> +static const TypeInfo colo_proxy_info = {
> +    .name = TYPE_FILTER_COLO_PROXY,
> +    .parent = TYPE_NETFILTER,
> +    .class_init = colo_proxy_class_init,
> +    .instance_init = colo_proxy_init,
> +    .instance_size = sizeof(ColoProxyState),
> +};
> +
> +static void register_types(void)
> +{
> +    type_register_static(&colo_proxy_info);
> +}
> +
> +type_init(register_types);
> diff --git a/net/colo-proxy.h b/net/colo-proxy.h
> new file mode 100644
> index 0000000..94afbc7
> --- /dev/null
> +++ b/net/colo-proxy.h
> @@ -0,0 +1,63 @@
> +/*
> + * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
> + * (a.k.a. Fault Tolerance or Continuous Replication)
> + *
> + * Copyright (c) 2015 HUAWEI TECHNOLOGIES CO., LTD.
> + * Copyright (c) 2015 FUJITSU LIMITED
> + * Copyright (c) 2015 Intel Corporation
> + *
> + * Author: Zhang Chen <address@hidden>
> + *
> + * 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_COLO_PROXY_H
> +#define QEMU_COLO_PROXY_H
> +
> +#include "net/filter.h"
> +#include "net/queue.h"
> +#include "qemu-common.h"
> +#include "qemu/iov.h"
> +#include "qapi/qmp/qerror.h"
> +#include "qapi-visit.h"
> +#include "qom/object.h"
> +#include "qemu/sockets.h"
> +#include "qemu/main-loop.h"
> +#include <netinet/if_ether.h>
> +#include "qemu/jhash.h"
> +#include "qemu/coroutine.h"

Don't include too many header files here. You should only include the header 
files
which will be used in this header file.

> +
> +#define FILTER_COLO_PROXY(obj) \
> +    OBJECT_CHECK(ColoProxyState, (obj), TYPE_FILTER_COLO_PROXY)
> +
> +#define TYPE_FILTER_COLO_PROXY "colo-proxy"
> +#define PRIMARY_MODE "primary"
> +#define SECONDARY_MODE "secondary"
> +
> +typedef enum {
> +    COLO_PRIMARY_MODE,               /* primary mode  */
> +    COLO_SECONDARY_MODE,             /* secondary mode */
> +} mode_type;
> +
> +typedef struct ColoProxyState {
> +    NetFilterState parent_obj;
> +    NetQueue *incoming_queue;        /* guest normal net queue */
> +    NetFilterDirection direction;    /* packet direction */
> +    mode_type colo_mode;             /* colo mode (primary or
> +                                      * secondary)
> +                                      */
> +    char *addr;                       /* primary colo connect addr
> +                                      * or secondary server addr
> +                                      */
> +    int sockfd;                      /* primary client socket fd or
> +                                      * secondary server socket fd
> +                                      */
> +    bool has_failover;               /* colo failover flag */
> +    GHashTable *unprocessed_packets; /* hashtable to save connection */
> +    GQueue unprocessed_connections;  /* to save unprocessed_connections */
> +    Coroutine *co;
> +} ColoProxyState;
> +
> +#endif /* QEMU_COLO_PROXY_H */
>