rdma_getaddrinfo

Translates the transport independent address to establish communication.

Syntax

#include <rdma/rdma_cma.h>
int rdma_getaddrinfo (char *node, char *service, struct rdma_addrinfo *hints, struct rdma_addrinfo **res);

Description

The rdma_getaddrinfo function resolves the destination node and service address and returns information that is required to establish communication. The function provides the RDMA functional equivalent to getaddrinfo.

Notes:

You must specify either node or service parameters for the translation. If hints are provided, the operation is controlled by the hints.ai_flags flag. If the RAI_PASSIVE flag is specified, the call resolves the address information that is used on the passive side of a connection.

Item	Description
ai_flags	Specifies the hint flags that control the operation. The following flags are supported: `RAI_PASSIVE`: Indicates that the results are used on the passive or listening side of a connection. `RAI_NUMERICHOST`: Indicates that if the flag is specified and if the node parameter is provided, the network address must be a numerical value. This flag suppresses any lengthy address resolution. `RAI_NOROUTE`: Indicates that if the flag is set, the flag suppresses any lengthy route resolution.
ai_family	Specifies the address family for the source and destination address. The supported families are `AF_IB`, `AF_INET`, and `AF_INET6`.
ai_qp_type	Indicates the type of RDMA QP used for communication. The types that are supported are `IBV_UD` (unreliable datagram) and `IBV_RC` (reliable connected).
ai_port_space	Indicates the RDMA port space that is in use. The supported values are `RDMA_PS_UDP` and `RDMA_PS_TCP`.
ai_src_len	Indicates the length of the source address that is referenced by the `ai_src_addr` flag. If an appropriate source address for a given destination is not discovered the value of the `ai_src_len` flag is 0.
ai_dst_len	Indicates the length of the destination address that is referenced by `ai_src_addr` flag. This flag is set to 0, if the `RAI_PASSIVE` flag was specified as part of the hints.
ai_src_addr	Specifies the address for the local RDMA device, if the RDMA device is provided.
ai_dst_addr	Specifies the destination address for the RDMA device, if the RDMA device is provided.
ai_src_canonname	Specifies the canonical for the source.
ai_dst_canonname	Specifies the canonical for the destination.
ai_route_len	Specifies the size of the routing information buffer that is referenced by the `ai_route` flag. If the transport does not require routing data or none of the address could be resolved, the `ai_route` flag is 0.
ai_connect_len	Specifies the routing information for RDMA transports that require routing data for establishing the connection. The format of the routing data depends on the underlying transport. If InfiniBand transports are used, the `ai_route` flag references an array of `ibv_path_data` structures.
ai_connect	Specifies the size of connection information referenced by `ai_route` flag. If the underlying transport does not require any additional information to establish connection, the `ai_connect` flag is set to 0.
ai_next	Specifies the pointer to the next `rdma_addrinfo` structure in the list. The `ai_next` flag is NULL if no structures exist.

Parameters

Item	Description
hints	Specifies a reference to a `rdma_addrinfo` structure containing hints about the type of service the caller supports.
node	Specifies the optional name, dotted-decimal IPv4 or IPv6 hexadecimal address that must be resolved.
res	Specifies a pointer to a linked list of `rdma_addrinfo` structures that contains the response information.
service	Specifies the service name or port number of the address.

Return Values

Returns 0 on success, or -1 on error. If an error occurs, then errno is set to indicate the reason for failure.