NAME¶
rdma_create_ep - Allocate a communication identifier and optional QP.
SYNOPSIS¶
#include <rdma/rdma_cma.h>
int rdma_create_ep (struct rdma_cm_id **id,
struct rdma_addrinfo *res, struct ibv_pd
*pd, struct ibv_qp_init_attr
*qp_init_attr);
ARGUMENTS¶
- id
- A reference where the allocated communication identifier
will be returned.
- res
- Address information associated with the rdma_cm_id returned
from rdma_getaddrinfo.
- pd
- Optional protection domain if a QP is associated with the
rdma_cm_id.
- qp_init_attr
- Optional initial QP attributes.
DESCRIPTION¶
Creates an identifier that is used to track communication information.
RETURN VALUE¶
Returns 0 on success, or -1 on error. If an error occurs, errno will be set to
indicate the failure reason.
NOTES¶
After resolving address information using rdma_getaddrinfo, a user may use this
call to allocate an rdma_cm_id based on the results.
If the rdma_cm_id will be used on the active side of a connection, meaning that
res->ai_flag does not have RAI_PASSIVE set, rdma_create_ep will
automatically create a QP on the rdma_cm_id if qp_init_attr is not NULL. The
QP will be associated with the specified protection domain, if provided, or a
default protection domain if not. Users should see rdma_create_qp for details
on the use of the pd and qp_init_attr parameters. After calling
rdma_create_ep, the returned rdma_cm_id may be connected by calling
rdma_connect. The active side calls rdma_resolve_addr and rdma_resolve_route
are not necessary.
If the rdma_cm_id will be used on the passive side of a connection, indicated by
having res->ai_flag RAI_PASSIVE set, this call will save the provided pd
and qp_init_attr parameters. When a new connection request is retrieved by
calling rdma_get_request, the rdma_cm_id associated with the new connection
will automatically be associated with a QP using the pd and qp_init_attr
parameters. After calling rdma_create_ep, the returned rdma_cm_id may be
placed into a listening state by immediately calling rdma_listen. The passive
side call rdma_bind_addr is not necessary. Connection requests may then be
retrieved by calling rdma_get_request.
The newly created rdma_cm_id will be set to use synchronous operation. Users
that wish asynchronous operation must migrate the rdma_cm_id to a user created
event channel using rdma_migrate_id.
Users must release the created rdma_cm_id by calling rdma_destroy_ep.
SEE ALSO¶
rdma_cm(7),
rdma_getaddrinfo(3),
rdma_create_event_channel(3),
rdma_connect(3),
rdma_listen(3),
rdma_destroy_ep(3),
rdma_migrate_id(3)