Re: [Qemu-devel] [PATCH v3 For-1.6 1/7] rdma: bugfix: make IPv6 support work

[Michael R. Hines]

On 08/07/2013 04:39 AM, Orit Wasserman wrote:

On 08/04/2013 05:54 AM, mrhi...@linux.vnet.ibm.com wrote:

From: "Michael R. Hines" <mrhi...@us.ibm.com>

RDMA does not use sockets, so we cannot use many of the socket
helper functions, but we *do* use inet_parse() which gives
RDMA all the necessary details of the connection parameters.

However, when testing with libvirt, a simple IPv6 migration test failed
because we were not using getaddrinfo() properly.

This makes IPv6 migration over RDMA work.

Signed-off-by: Michael R. Hines <mrhi...@us.ibm.com>
---
  migration-rdma.c |   33 +++++++++++++++++++++------------
  1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/migration-rdma.c b/migration-rdma.c
index d044830..9cf73e3 100644
--- a/migration-rdma.c
+++ b/migration-rdma.c
@@ -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;

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);

Hi Michael,

getaddrinfo can return a list of addresses, you need to handle it.
Look at qemu-sockets.c for example.

Regards,
Orit

+        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);

Acknowledged.

- Michael