A method for providing remote access redirect in a host channel adapter of
a system area network are provided. The method provides a mechanism by
which a host channel adapter, in response to receiving a marker message,
places selected channel(s) of the host channel adapter in a remote access
redirect (RAR) mode of operation. During the RAR mode of operation,
memory access messages received by the host channel adapter that are
destined for portions of an application memory space marked as being
protected are converted to RAR receive messages and redirected to a queue
pair associated with an operating system rather than the queue pair for
the application. The operating system is responsible for serializing
access to application memory pages outside of the host channel adapter.
The mechanisms of the present invention may be used to perform a
checkpoint data integrity operation.