net: mctp: usblib: Add support for multi-packet transmit

Browse source

The MCTP over USB spec allows us to pack multiple packets in one
transfer. Given the packet max length is 255, and the transfer max
length is 512, we can typically include two full-size packets per
urb submission.

To do this, we allow a struct mctp_usb_tx to persist a tx_ctx,
representing the ongoing context for a transmit. If possible, a TX skb
will be queued to the context and the send deferred until the context is
full, or the device queue reports no more packets.

This typically requires a linear buffer for the 512-byte TX, which we
allocate along with the TX context.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://patch.msgid.link/20260724-dev-mctp-usb-1-1-v5-6-e66bbba0dbdc@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

...

This commit is contained in:

Jeremy Kerr 2026-07-24 13:15:27 +08:00 • committed by Jakub Kicinski

parent aadf5ed03e

commit 76a58ffd74

2 changed files with 210 additions and 50 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

262

drivers/net/mctp/mctp-usblib.c

View file

8

include/linux/usb/mctp-usb.h

View file