SVR5

mdi_valid_mca(D3mdi)

mdi_valid_mca -- Verify that the specified multicast address has been set for this adapter

Synopsis

   #include <sys/types.h>
   #include <sys/stream.h>
   #include <sys/stropt.h>
   #include <sys/mdi.h>
   #include <sys/ddi.h>
   
   int mdi_valid_mca (void *mac_cookie, macaddr_t addr);

Description

mdi_valid_mca( ) verifies that the specified multicast address has been set for this adapter.

Arguments

mac_cookie: The mac_cookie value passed in the mac_bind_req structure returned by the MAC_BIND_REQ(D7mdi) primitive.
addr: multicast address being checked

Return values

mdi_valid_mca( ) returns TRUE if the specified multicast address is valid for this adapter. If not, it returns FALSE.

Usage

The mdi_valid_mca( ) function does a quick hash lookup, with no address comparison, of the same multicast address table that the mdi_get_mctable(D3mdi) function searches. It is used during packet reception, to avoid the overhead of searching through what could be a very large hash table. Specifically, it is used in the following situations:

To determine if a transmit packet sent to multicast destination addresses needs to be looped back with the mdi_do_loopback(D3mdi) function.
To determine if a received packet sent to multicast destination addresses should be sent to the MDI user. This is especially useful for hardware with imperfect multicast address matching, such as those that use some type of address mask or a hashing function.

Drivers should use the mdi_get_mctable(D3mdi) function to check if the given multicast address exists for the adapter when processing the MACIOC_SETMCA and MACIOC_DELMCA ioctls.

Context and synchronization

Any context

Hardware applicability

All

Version applicability

mdi: 2, 2.1

Differences between versions

This function is not supported in MDI on SCO OpenServer systems.

References

mdi_do_loopback(D3mdi), mdi_get_mctable(D3mdi), Intro(MDI) (on OpenServer 6), Intro(7mdi) (on UnixWare 7.1.4)

``Multicast addresses and failover'' in HDK Technical Reference