Re: [Qemu-devel] [PATCH] rdma: bugfix: make IPv6 support work

[Orit Wasserman <owasserm@redhat.com>]

On 07/31/2013 04:39 PM, Michael R. Hines wrote:
> On 07/30/2013 11:31 AM, Orit Wasserman wrote:
>> On 07/30/2013 05:57 PM, Michael R. Hines wrote:
>>> On 07/30/2013 04:14 AM, Orit Wasserman wrote:
>>>> On 07/27/2013 05:23 AM, mrhines@linux.vnet.ibm.com wrote:
>>>>> From: "Michael R. Hines" <mrhines@us.ibm.com>
>>>>>
>>>>> When testing with libvirt, a simple IPv6 migration test failed
>>>>> because we were not using getaddrinfo() properly.
>>>>> This makes IPv6 migration over RDMA work.
>>>>>
>>>>> Also, we forgot to turn the DPRINTF flag off =).
>>>>>
>>>>> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com>
>>>>> ---
>>>>>    migration-rdma.c |   35 ++++++++++++++++++++++-------------
>>>>>    1 file changed, 22 insertions(+), 13 deletions(-)
>>>>>
>>>>> diff --git a/migration-rdma.c b/migration-rdma.c
>>>>> index d044830..3256c9b 100644
>>>>> --- a/migration-rdma.c
>>>>> +++ b/migration-rdma.c
>>>>> @@ -27,7 +27,7 @@
>>>>>    #include <string.h>
>>>>>    #include <rdma/rdma_cma.h>
>>>>>    -#define DEBUG_RDMA
>>>>> +//#define DEBUG_RDMA
>>>> Can you put this in a separate patch?
>>> Acknowledged.
>>>
>>>>>    //#define DEBUG_RDMA_VERBOSE
>>>>>    //#define DEBUG_RDMA_REALLY_VERBOSE
>>>>>    @@ -392,6 +392,7 @@ typedef struct RDMAContext {
>>>>>        uint64_t unregistrations[RDMA_SIGNALED_SEND_MAX];
>>>>>          GHashTable *blockmap;
>>>>> +    bool ipv6;
>>>>>    } RDMAContext;
>>>>>      /*
>>>>> @@ -744,6 +745,7 @@ static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp)
>>>>>        char port_str[16];
>>>>>        struct rdma_cm_event *cm_event;
>>>>>        char ip[40] = "unknown";
>>>>> +    int af = rdma->ipv6 ? PF_INET6 : PF_INET;
>>>> We have code that handles ipv6 in utils/qemu-sockets.c, it also handle host
>>>> and port parsing please take a look at inet_parse_connect_opts.
>>>> I think it can be reused here and for the destination.
>>> RDMA cannot use that function - it creates a socket and RDMA does not use sockets.
>>>
>>> RDMA is *already*, however, using inet_parse() which does exactly what you said.
>>>
>> You can update the function so it can be used for RDMA also.
> 
> The inet_parse() function does everything that we need -
> it already understands IPv6 without opening an actual socket.
> 
> Any more than that would require CONFIG_RDMA to be
> conditionalized inside of the utils/ source code,
> and that seems like a lot of work for such a small reward.
> 

Agreed,
Orit

> - Michael
> 
>> Orit
>>
>>>> Regards,
>>>> Orit
>>>>>          if (rdma->host == NULL || !strcmp(rdma->host, "")) {
>>>>>            ERROR(errp, "RDMA hostname has not been set\n");
>>>>> @@ -773,7 +775,7 @@ static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp)
>>>>>            goto err_resolve_get_addr;
>>>>>        }
>>>>>    -    inet_ntop(AF_INET, &((struct sockaddr_in *) res->ai_addr)->sin_addr,
>>>>> +    inet_ntop(af, &((struct sockaddr_in *) res->ai_addr)->sin_addr,
>>>>>                                    ip, sizeof ip);
>>>>>        DPRINTF("%s => %s\n", rdma->host, ip);
>>>>>    @@ -2236,9 +2238,12 @@ err_rdma_source_connect:
>>>>>    static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp)
>>>>>    {
>>>>>        int ret = -EINVAL, idx;
>>>>> +    int af = rdma->ipv6 ? PF_INET6 : PF_INET;
>>>>>        struct sockaddr_in sin;
>>>>>        struct rdma_cm_id *listen_id;
>>>>>        char ip[40] = "unknown";
>>>>> +    struct addrinfo *res;
>>>>> +    char port_str[16];
>>>>>          for (idx = 0; idx <= RDMA_WRID_MAX; idx++) {
>>>>>            rdma->wr_data[idx].control_len = 0;
>>>>> @@ -2266,27 +2271,30 @@ static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp)
>>>>>        }
>>>>>          memset(&sin, 0, sizeof(sin));
>>>>> -    sin.sin_family = AF_INET;
>>>>> +    sin.sin_family = af;
>>>>>        sin.sin_port = htons(rdma->port);
>>>>> +    snprintf(port_str, 16, "%d", rdma->port);
>>>>> +    port_str[15] = '\0';
>>>>>          if (rdma->host && strcmp("", rdma->host)) {
>>>>> -        struct hostent *dest_addr;
>>>>> -        dest_addr = gethostbyname(rdma->host);
>>>>> -        if (!dest_addr) {
>>>>> -            ERROR(errp, "migration could not gethostbyname!\n");
>>>>> -            ret = -EINVAL;
>>>>> +        ret = getaddrinfo(rdma->host, port_str, NULL, &res);
>>>>> +        if (ret < 0) {
>>>>> +            ERROR(errp, "could not getaddrinfo address %s\n", rdma->host);
>>>>>                goto err_dest_init_bind_addr;
>>>>>            }
>>>>> -        memcpy(&sin.sin_addr.s_addr, dest_addr->h_addr,
>>>>> -                dest_addr->h_length);
>>>>> -        inet_ntop(AF_INET, dest_addr->h_addr, ip, sizeof ip);
>>>>> +
>>>>> +
>>>>> +        inet_ntop(af, &((struct sockaddr_in *) res->ai_addr)->sin_addr,
>>>>> +                                    ip, sizeof ip);
>>>>>        } else {
>>>>> -        sin.sin_addr.s_addr = INADDR_ANY;
>>>>> +        ERROR(errp, "migration host and port not specified!\n");
>>>>> +        ret = -EINVAL;
>>>>> +        goto err_dest_init_bind_addr;
>>>>>        }
>>>>>          DPRINTF("%s => %s\n", rdma->host, ip);
>>>>>    -    ret = rdma_bind_addr(listen_id, (struct sockaddr *)&sin);
>>>>> +    ret = rdma_bind_addr(listen_id, res->ai_addr);
>>>>>        if (ret) {
>>>>>            ERROR(errp, "Error: could not rdma_bind_addr!\n");
>>>>>            goto err_dest_init_bind_addr;
>>>>> @@ -2321,6 +2329,7 @@ static void *qemu_rdma_data_init(const char *host_port, Error **errp)
>>>>>            if (addr != NULL) {
>>>>>                rdma->port = atoi(addr->port);
>>>>>                rdma->host = g_strdup(addr->host);
>>>>> +            rdma->ipv6 = addr->ipv6;
>>>>>            } else {
>>>>>                ERROR(errp, "bad RDMA migration address '%s'", host_port);
>>>>>                g_free(rdma);
>>>>>
>