enic: add admin channel open and close for SR-IOV

The V2 SR-IOV design uses a dedicated admin channel (WQ/RQ/CQ
resources plus an MSI-X interrupt) for PF-VF mailbox communication rather
than firmware-proxied devcmds.

Introduce enic_admin_channel_open() and enic_admin_channel_close().
Open allocates and initialises the admin WQ, RQ, and two CQs (one per
direction), then issues CMD_QP_TYPE_SET to tell firmware the queues are
admin-type. Close reverses the sequence.

enic_admin_wq_buf_clean() unmaps and frees any WQ buffers still held
at close time, fixing a DMA mapping leak when a send times out.

Add CMD_QP_TYPE_SET (97), QP_TYPE_ADMIN/DATA, and QP_ENABLE/QP_DISABLE
defines to vnic_devcmd.h. Add VNIC_CQ_* named constants to vnic_cq.h
so CQ initialisation parameters are self-documenting from their first
introduction.

Signed-off-by: Satish Kharat <satishkh@cisco.com>
Link: https://patch.msgid.link/20260812-enic-sriov-v2-admin-channel-v2-v13-2-b3809e448aba@cisco.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Satish Kharat 2026-08-12 05:48:02 -07:00 • committed by Jakub Kicinski
commit 3258931d40
6 changed files with 269 additions and 1 deletions