MAC_MAXSDU_UPDATE(9F) Kernel Functions for Drivers MAC_MAXSDU_UPDATE(9F)
- indicate that a device's maximum data size has changed
SYNOPSIS #include <sys/mac_provider.h> int mac_maxsdu_update
, uint_t sdu
illumos DDI specific
The MAC handle obtained from a call to mac_register(9F)
An integer representing the maximum size data payload.
() function is used to inform the MAC layer that the
device represented by the handle mh
has changed the largest size frame that
it can transmit, also known as its Send Data Unit (SDU). This should be
called when the device's MTU has been requested to be changed when a
entry point has been called with the property MAC_PROP_MTU
or some other device-related event occurring.
represents the size of the largest payload ignoring the size of its
own headers or any margin. For example, for an Ethernet-based device, this
size should not include the Ethernet header or any VLAN tags.
Through VNICs and other virtual data links, many different devices may be
using a single physical device and have their own MTUs. The system takes
care of those concerns and will not ask a device driver to update the MTU
without verifying this.
Upon successful completion, the mac_maxsdu_update
() function returns 0
Otherwise, a non-negative error is returned.
For an example of how a device driver should use the mac_maxsdu_update
function, see the EXAMPLES
section in mc_setprop(9E)
() function may fail if:
EINVAL The specified sdu
is lower than the minimum SDU of the
SEE ALSO mac(9E)
OmniOS June 2, 2016 OmniOS