qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
To: Jason Wang <jasowang@redhat.com>, qemu devel <qemu-devel@nongnu.org>
Cc: Li Zhijian <lizhijian@cn.fujitsu.com>,
	Wen Congyang <wency@cn.fujitsu.com>,
	"eddie . dong" <eddie.dong@intel.com>,
	"Dr . David Alan Gilbert" <dgilbert@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] net/net: Add ReadState for reuse codes
Date: Wed, 11 May 2016 19:20:23 +0800	[thread overview]
Message-ID: <57331577.2090206@cn.fujitsu.com> (raw)
In-Reply-To: <5732F4FF.5060206@redhat.com>



On 05/11/2016 05:01 PM, Jason Wang wrote:
>
>
> On 2016年05月06日 18:56, Zhang Chen wrote:
>> 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>
>
> Looks good, just few nits.
>
> It's better to have a commit log.

OK, I will add this log:

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.

>
>> ---
>>   include/net/net.h   |  8 ++++++
>>   net/filter-mirror.c | 60 ++++++++------------------------------------
>>   net/net.c           | 56 ++++++++++++++++++++++++++++++++++++++++++
>>   net/socket.c        | 71 
>> +++++++++++++----------------------------------------
>>   4 files changed, 91 insertions(+), 104 deletions(-)
>>
>> diff --git a/include/net/net.h b/include/net/net.h
>> index 73e4c46..1439cf9 100644
>> --- a/include/net/net.h
>> +++ b/include/net/net.h
>> @@ -102,6 +102,14 @@ typedef struct NICState {
>>       bool peer_deleted;
>>   } NICState;
>>   +typedef struct ReadState {
>> +    int state; /* 0 = getting length, 1 = getting data */
>> +    uint32_t index;
>> +    uint32_t packet_len;
>> +    uint8_t buf[NET_BUFSIZE];
>> +} ReadState;
>
> I think SocketReadState is better here.
>

I will rename it in next version.

>> +
>> +int net_fill_rstate(ReadState *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,
>> diff --git a/net/filter-mirror.c b/net/filter-mirror.c
>> index c0c4dc6..bcec509 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];
>> +    ReadState rs;
>>   } MirrorState;
>>     static int filter_mirror_send(CharDriverState *chr_out,
>> @@ -108,51 +105,14 @@ 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) {
>> +        redirector_to_filter(nf, s->rs.buf, s->rs.packet_len);
>>       }
>>   }
>>   @@ -274,7 +234,7 @@ static void 
>> filter_redirector_setup(NetFilterState *nf, Error **errp)
>>           }
>>       }
>>   -    s->state = s->index = 0;
>> +    s->rs.state = s->rs.index = 0;
>>         if (s->indev) {
>>           s->chr_in = qemu_chr_find(s->indev);
>> diff --git a/net/net.c b/net/net.c
>> index 0ad6217..926457e 100644
>> --- a/net/net.c
>> +++ b/net/net.c
>> @@ -1573,3 +1573,59 @@ QemuOptsList qemu_net_opts = {
>>           { /* end of list */ }
>>       },
>>   };
>> +
>> +/*
>> + * Returns
>> + * 0: readstate is not ready
>> + * 1: readstate is ready
>> + * otherwise error occurs
>> + */
>> +int net_fill_rstate(ReadState *rs, const uint8_t *buf, int size)
>> +{
>> +    unsigned int l;
>> +    while (size > 0) {
>> +        /* reassemble a packet from the network */
>> +        switch (rs->state) { /* 0 = getting length, 1 = getting data */
>> +        case 0:
>> +            l = 4 - rs->index;
>> +            if (l > size) {
>> +                l = size;
>> +            }
>> +            memcpy(rs->buf + rs->index, buf, l);
>> +            buf += l;
>> +            size -= l;
>> +            rs->index += l;
>> +            if (rs->index == 4) {
>> +                /* got length */
>> +                rs->packet_len = ntohl(*(uint32_t *)rs->buf);
>> +                rs->index = 0;
>> +                rs->state = 1;
>> +            }
>> +            break;
>> +        case 1:
>> +            l = rs->packet_len - rs->index;
>> +            if (l > size) {
>> +                l = size;
>> +            }
>> +            if (rs->index + l <= sizeof(rs->buf)) {
>> +                memcpy(rs->buf + rs->index, buf, l);
>> +            } else {
>> +                fprintf(stderr, "serious error: oversized packet 
>> received,"
>> +                    "connection terminated.\n");
>> +                rs->index = rs->state = 0;
>> +                return -1;
>> +            }
>> +
>> +            rs->index += l;
>> +            buf += l;
>> +            size -= l;
>> +            if (rs->index >= rs->packet_len) {
>> +                rs->index = 0;
>> +                rs->state = 0;
>> +                return 1;
>> +            }
>> +            break;
>> +        }
>> +    }
>> +    return 0;
>> +}
>> diff --git a/net/socket.c b/net/socket.c
>> index 9fa2cd8..9ecdd3b 100644
>> --- a/net/socket.c
>> +++ b/net/socket.c
>> @@ -38,11 +38,8 @@ typedef struct NetSocketState {
>>       NetClientState nc;
>>       int listen_fd;
>>       int fd;
>> -    int state; /* 0 = getting length, 1 = getting data */
>> -    unsigned int index;
>> -    unsigned int packet_len;
>> +    ReadState rs;
>>       unsigned int send_index;      /* number of bytes sent (only 
>> SOCK_STREAM) */
>> -    uint8_t buf[NET_BUFSIZE];
>>       struct sockaddr_in dgram_dst; /* contains inet host and port 
>> destination iff connectionless (SOCK_DGRAM) */
>>       IOHandler *send_fn;           /* differs between 
>> SOCK_STREAM/SOCK_DGRAM */
>>       bool read_poll;               /* waiting to receive data? */
>> @@ -147,7 +144,7 @@ static void net_socket_send(void *opaque)
>>   {
>>       NetSocketState *s = opaque;
>>       int size;
>> -    unsigned l;
>> +    int ret;
>>       uint8_t buf1[NET_BUFSIZE];
>>       const uint8_t *buf;
>>   @@ -166,60 +163,26 @@ static void net_socket_send(void *opaque)
>>           closesocket(s->fd);
>>             s->fd = -1;
>> -        s->state = 0;
>> -        s->index = 0;
>> -        s->packet_len = 0;
>> +        s->rs.state = 0;
>> +        s->rs.index = 0;
>> +        s->rs.packet_len = 0;
>>           s->nc.link_down = true;
>> -        memset(s->buf, 0, sizeof(s->buf));
>> +        memset(s->rs.buf, 0, sizeof(s->rs.buf));
>
> How about introduce a helper to do the initialization?

Do you mean

remove
+        s->rs.state = 0;
+        s->rs.index = 0;
+        s->rs.packet_len = 0;
+        memset(s->rs.buf, 0, sizeof(s->rs.buf));

add
            s->rs->cb = xxx_cb;
            s->rs->opxx = xxx;

void xxx_cb(void *opaque)
{
     NetSocketState *s = opaque;

     s->rs.state = 0;
     s->rs.index = 0;
     s->rs.packet_len = 0;
     memset(s->rs.buf, 0, sizeof(s->rs.buf));
}


>
>>           memset(s->nc.info_str, 0, sizeof(s->nc.info_str));
>>             return;
>>       }
>>       buf = buf1;
>> -    while (size > 0) {
>> -        /* reassemble a packet from the network */
>> -        switch(s->state) {
>> -        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 {
>> -                fprintf(stderr, "serious error: oversized packet 
>> received,"
>> -                    "connection terminated.\n");
>> -                s->state = 0;
>> -                goto eoc;
>> -            }
>>   -            s->index += l;
>> -            buf += l;
>> -            size -= l;
>> -            if (s->index >= s->packet_len) {
>> -                s->index = 0;
>> -                s->state = 0;
>> -                if (qemu_send_packet_async(&s->nc, s->buf, 
>> s->packet_len,
>> - net_socket_send_completed) == 0) {
>> -                    net_socket_read_poll(s, false);
>> -                    break;
>> -                }
>> -            }
>> -            break;
>> +    ret = net_fill_rstate(&s->rs, buf, size);
>> +
>> +    if (ret == -1) {
>> +        goto eoc;
>> +    } else if (ret == 1) {
>> +        if (qemu_send_packet_async(&s->nc, s->rs.buf,
>> +                                   s->rs.packet_len,
>> +                                   net_socket_send_completed) == 0) {
>> +            net_socket_read_poll(s, false);
>
> This looks not elegant, maybe we could use callback (which was 
> initialized by the helper I mention above) to do this. Any thoughts on 
> this?

Do you mean:

remove
+        if (qemu_send_packet_async(&s->nc, s->rs.buf,
+                                   s->rs.packet_len,
+                                   net_socket_send_completed) == 0) {
+            net_socket_read_poll(s, false);

add

s->rs->done

void socket_fill_rsstate_done_cb(SocketReadState *srs, void *opaque)
{
     NetSocketState *s = opaque;

     if (qemu_send_packet_async(&s->nc, srs->buf,
                                srs->packet_len,
                                net_socket_send_completed) == 0) {
         net_socket_read_poll(s, false);
     }
}

>
>>           }
>>       }
>>   }
>> @@ -229,7 +192,7 @@ static void net_socket_send_dgram(void *opaque)
>>       NetSocketState *s = opaque;
>>       int size;
>>   -    size = qemu_recv(s->fd, s->buf, sizeof(s->buf), 0);
>> +    size = qemu_recv(s->fd, s->rs.buf, sizeof(s->rs.buf), 0);
>>       if (size < 0)
>>           return;
>>       if (size == 0) {
>> @@ -238,7 +201,7 @@ static void net_socket_send_dgram(void *opaque)
>>           net_socket_write_poll(s, false);
>>           return;
>>       }
>> -    if (qemu_send_packet_async(&s->nc, s->buf, size,
>> +    if (qemu_send_packet_async(&s->nc, s->rs.buf, size,
>>                                  net_socket_send_completed) == 0) {
>>           net_socket_read_poll(s, false);
>>       }
>
>
>
> .
>

-- 
Thanks
zhangchen

  reply	other threads:[~2016-05-11 11:20 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-06 10:56 [Qemu-devel] [PATCH] net/net: Add ReadState for reuse codes Zhang Chen
2016-05-10  2:57 ` Li Zhijian
2016-05-10  5:33   ` Zhang Chen
2016-05-11  7:01   ` Zhang Chen
2016-05-11  9:01 ` Jason Wang
2016-05-11 11:20   ` Zhang Chen [this message]
2016-05-12  1:11     ` Jason Wang
2016-05-12  6:33       ` Zhang Chen
2016-05-12  8:07         ` Jason Wang
2016-05-12  8:23           ` Zhang Chen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=57331577.2090206@cn.fujitsu.com \
    --to=zhangchen.fnst@cn.fujitsu.com \
    --cc=dgilbert@redhat.com \
    --cc=eddie.dong@intel.com \
    --cc=jasowang@redhat.com \
    --cc=lizhijian@cn.fujitsu.com \
    --cc=qemu-devel@nongnu.org \
    --cc=wency@cn.fujitsu.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).