[iobuf] Increase minimum I/O buffer size to 128 bytes
authorMichael Brown <mcb30@ipxe.org>
Thu, 23 Mar 2017 16:15:24 +0000 (18:15 +0200)
committerMichael Brown <mcb30@ipxe.org>
Thu, 23 Mar 2017 16:29:46 +0000 (18:29 +0200)
commitb340971852912616de01b51848b224de23024177
treec4a951e718dac9c6feac42c3da867a04af7655da
parenta317e9a310d6ea5288edd39d9933e6c2fb2358aa
[iobuf] Increase minimum I/O buffer size to 128 bytes

The eIPoIB translation layer needs to translate outbound ARP packets
from Ethernet to IPoIB.  A 64-byte buffer (starting with the Ethernet
header) does not provide enough tailroom to expand to hold the two
20-byte IPoIB MAC addresses.  The result is that an UNDI API user will
be unable to send ARP packets.

We could potentially shuffle the packet contents to reuse the space
occupied by the stripped Ethernet link-layer header, but this would
add complexity.  Instead, fix by increasing the minimum allocation
size to 128 bytes.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
src/include/ipxe/iobuf.h