Re: [Qemu-devel] [PATCH V2] net/net: Add SocketReadState for reuse codes

[Zhang Chen <zhangchen.fnst@cn.fujitsu.com>]

On 05/13/2016 12:02 PM, Jason Wang wrote:
>
>
> On 2016年05月12日 17:19, Zhang Chen wrote:
>> This function is from net/socket.c, move it to net.c and net.h.
>> Add SocketReadState to make others reuse net_fill_rstate().
>> suggestion from jason.
>>
>> v2:
>>   - rename ReadState to SocketReadState
>>   - add SocketReadState init and finalize callback
>>
>> v1:
>>   - init patch
>>
>> Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
>> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
>> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
>> ---
>>   include/net/net.h   | 14 +++++++++
>>   net/filter-mirror.c | 72 ++++++++++++++-----------------------------
>>   net/net.c           | 65 ++++++++++++++++++++++++++++++++++++++
>>   net/socket.c        | 89 
>> +++++++++++++++++++++--------------------------------
>>   4 files changed, 137 insertions(+), 103 deletions(-)
>>
>> diff --git a/include/net/net.h b/include/net/net.h
>> index 73e4c46..4f6b6bf 100644
>> --- a/include/net/net.h
>> +++ b/include/net/net.h
>> @@ -57,6 +57,9 @@ typedef void (SetOffload)(NetClientState *, int, 
>> int, int, int, int);
>>   typedef void (SetVnetHdrLen)(NetClientState *, int);
>>   typedef int (SetVnetLE)(NetClientState *, bool);
>>   typedef int (SetVnetBE)(NetClientState *, bool);
>> +typedef struct SocketReadState SocketReadState;
>> +typedef void (SocketReadStateInit)(SocketReadState *rs);
>> +typedef void (SocketReadStateFinalize)(SocketReadState *rs);
>>     typedef struct NetClientInfo {
>>       NetClientOptionsKind type;
>> @@ -102,6 +105,16 @@ typedef struct NICState {
>>       bool peer_deleted;
>>   } NICState;
>>   +struct SocketReadState {
>> +    int state; /* 0 = getting length, 1 = getting data */
>> +    uint32_t index;
>> +    uint32_t packet_len;
>> +    uint8_t buf[NET_BUFSIZE];
>> +    SocketReadStateInit *init;
>> +    SocketReadStateFinalize *finalize;
>> +};
>> +
>> +int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size);
>>   char *qemu_mac_strdup_printf(const uint8_t *macaddr);
>>   NetClientState *qemu_find_netdev(const char *id);
>>   int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
>> @@ -160,6 +173,7 @@ ssize_t qemu_deliver_packet_iov(NetClientState 
>> *sender,
>>     void print_net_client(Monitor *mon, NetClientState *nc);
>>   void hmp_info_network(Monitor *mon, const QDict *qdict);
>> +void net_socket_rs_init(SocketReadState *rs);
>>     /* NIC info */
>>   diff --git a/net/filter-mirror.c b/net/filter-mirror.c
>> index c0c4dc6..4e55924 100644
>> --- a/net/filter-mirror.c
>> +++ b/net/filter-mirror.c
>> @@ -40,10 +40,7 @@ typedef struct MirrorState {
>>       char *outdev;
>>       CharDriverState *chr_in;
>>       CharDriverState *chr_out;
>> -    int state; /* 0 = getting length, 1 = getting data */
>> -    unsigned int index;
>> -    unsigned int packet_len;
>> -    uint8_t buf[REDIRECTOR_MAX_LEN];
>> +    SocketReadState rs;
>>   } MirrorState;
>>     static int filter_mirror_send(CharDriverState *chr_out,
>> @@ -108,50 +105,15 @@ static void redirector_chr_read(void *opaque, 
>> const uint8_t *buf, int size)
>>   {
>>       NetFilterState *nf = opaque;
>>       MirrorState *s = FILTER_REDIRECTOR(nf);
>> -    unsigned int l;
>> -
>> -    while (size > 0) {
>> -        /* reassemble a packet from the network */
>> -        switch (s->state) { /* 0 = getting length, 1 = getting data */
>> -        case 0:
>> -            l = 4 - s->index;
>> -            if (l > size) {
>> -                l = size;
>> -            }
>> -            memcpy(s->buf + s->index, buf, l);
>> -            buf += l;
>> -            size -= l;
>> -            s->index += l;
>> -            if (s->index == 4) {
>> -                /* got length */
>> -                s->packet_len = ntohl(*(uint32_t *)s->buf);
>> -                s->index = 0;
>> -                s->state = 1;
>> -            }
>> -            break;
>> -        case 1:
>> -            l = s->packet_len - s->index;
>> -            if (l > size) {
>> -                l = size;
>> -            }
>> -            if (s->index + l <= sizeof(s->buf)) {
>> -                memcpy(s->buf + s->index, buf, l);
>> -            } else {
>> -                error_report("serious error: oversized packet 
>> received.");
>> -                s->index = s->state = 0;
>> -                qemu_chr_add_handlers(s->chr_in, NULL, NULL, NULL, 
>> NULL);
>> -                return;
>> -            }
>> -
>> -            s->index += l;
>> -            buf += l;
>> -            size -= l;
>> -            if (s->index >= s->packet_len) {
>> -                s->index = 0;
>> -                s->state = 0;
>> -                redirector_to_filter(nf, s->buf, s->packet_len);
>> -            }
>> -            break;
>> +    int ret;
>> +
>> +    ret = net_fill_rstate(&s->rs, buf, size);
>> +
>> +    if (ret == -1) {
>> +        qemu_chr_add_handlers(s->chr_in, NULL, NULL, NULL, NULL);
>> +    } else if (ret == 1) {
>> +        if (s->rs.finalize) {
>> +            s->rs.finalize(&s->rs);
>
> Why not simply call this in net_fill_rstate()?

Good idea.
I will move it in next version.


>
>>           }
>>       }
>>   }
>> @@ -258,6 +220,14 @@ static void filter_mirror_setup(NetFilterState 
>> *nf, Error **errp)
>>       }
>>   }
>>   +static void redirector_rs_finalize(SocketReadState *rs)
>> +{
>> +    MirrorState *s = container_of(rs, MirrorState, rs);
>> +    NetFilterState *nf = NETFILTER(s);
>> +
>> +    redirector_to_filter(nf, rs->buf, rs->packet_len);
>> +}
>> +
>>   static void filter_redirector_setup(NetFilterState *nf, Error **errp)
>>   {
>>       MirrorState *s = FILTER_REDIRECTOR(nf);
>> @@ -274,7 +244,11 @@ static void 
>> filter_redirector_setup(NetFilterState *nf, Error **errp)
>>           }
>>       }
>>   -    s->state = s->index = 0;
>> +    s->rs.init = net_socket_rs_init;
>> +    s->rs.finalize = redirector_rs_finalize;
>> +    if (s->rs.init) {
>> +        s->rs.init(&s->rs);
>> +    }
>
> This looks odd, you can call net_socket_rs_init() directly here and 
> pass redirector_rs_finalize to it. Then there's no need to do the open 
> code here.
>
>

OK

Thanks
Zhang Chen

>
> .
>

-- 
Thanks
zhangchen