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

[Michael R. Hines]

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, address@hidden wrote:
> > > > From: "Michael R. Hines" <address@hidden>
> > > >
> > > > 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 <address@hidden>
> > > > ---
> > > >    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.

- 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);