RDMA/ucma: Add ability to query GID addresses

Part of address resolution is mapping IP addresses to IB GIDs.  With
the changes to support querying larger addresses and more path records,
also provide a way to query IB GIDs after resolution completes.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/core/ucma.c

@@ -48,6 +48,7 @@
 #include <rdma/rdma_cm.h>
 #include <rdma/rdma_cm_ib.h>
 #include <rdma/ib_addr.h>
+#include <rdma/ib.h>
 
 MODULE_AUTHOR("Sean Hefty");
 MODULE_DESCRIPTION("RDMA Userspace Connection Manager Access");
@@ -782,6 +783,52 @@ static ssize_t ucma_query_path(struct ucma_context *ctx,
 	return ret;
 }
 
+static ssize_t ucma_query_gid(struct ucma_context *ctx,
+			      void __user *response, int out_len)
+{
+	struct rdma_ucm_query_addr_resp resp;
+	struct sockaddr_ib *addr;
+	int ret = 0;
+
+	if (out_len < sizeof(resp))
+		return -ENOSPC;
+
+	memset(&resp, 0, sizeof resp);
+
+	ucma_query_device_addr(ctx->cm_id, &resp);
+
+	addr = (struct sockaddr_ib *) &resp.src_addr;
+	resp.src_size = sizeof(*addr);
+	if (ctx->cm_id->route.addr.src_addr.ss_family == AF_IB) {
+		memcpy(addr, &ctx->cm_id->route.addr.src_addr, resp.src_size);
+	} else {
+		addr->sib_family = AF_IB;
+		addr->sib_pkey = (__force __be16) resp.pkey;
+		rdma_addr_get_sgid(&ctx->cm_id->route.addr.dev_addr,
+				   (union ib_gid *) &addr->sib_addr);
+		addr->sib_sid = rdma_get_service_id(ctx->cm_id, (struct sockaddr *)
+						    &ctx->cm_id->route.addr.src_addr);
+	}
+
+	addr = (struct sockaddr_ib *) &resp.dst_addr;
+	resp.dst_size = sizeof(*addr);
+	if (ctx->cm_id->route.addr.dst_addr.ss_family == AF_IB) {
+		memcpy(addr, &ctx->cm_id->route.addr.dst_addr, resp.dst_size);
+	} else {
+		addr->sib_family = AF_IB;
+		addr->sib_pkey = (__force __be16) resp.pkey;
+		rdma_addr_get_dgid(&ctx->cm_id->route.addr.dev_addr,
+				   (union ib_gid *) &addr->sib_addr);
+		addr->sib_sid = rdma_get_service_id(ctx->cm_id, (struct sockaddr *)
+						    &ctx->cm_id->route.addr.dst_addr);
+	}
+
+	if (copy_to_user(response, &resp, sizeof(resp)))
+		ret = -EFAULT;
+
+	return ret;
+}
+
 static ssize_t ucma_query(struct ucma_file *file,
 			  const char __user *inbuf,
 			  int in_len, int out_len)
@@ -806,6 +853,9 @@ static ssize_t ucma_query(struct ucma_file *file,
 	case RDMA_USER_CM_QUERY_PATH:
 		ret = ucma_query_path(ctx, response, out_len);
 		break;
+	case RDMA_USER_CM_QUERY_GID:
+		ret = ucma_query_gid(ctx, response, out_len);
+		break;
 	default:
 		ret = -ENOSYS;
 		break;

include/uapi/rdma/rdma_user_cm.h

@@ -116,7 +116,8 @@ struct rdma_ucm_resolve_route {
 
 enum {
 	RDMA_USER_CM_QUERY_ADDR,
-	RDMA_USER_CM_QUERY_PATH
+	RDMA_USER_CM_QUERY_PATH,
+	RDMA_USER_CM_QUERY_GID
 };
 
 struct rdma_ucm_query {