[PATCH net-next v9 0/6] net: mana: Per-vPort EQ and MSI-X interrupt management

[Long Li <longli@microsoft.com>]

This series moves EQ ownership from the shared mana_context to per-vPort
mana_port_context, enabling each vPort to have dedicated MSI-X vectors
when the hardware provides enough vectors. When vectors are limited, the
driver falls back to sharing MSI-X among vPorts.

The series introduces a GDMA IRQ Context (GIC) abstraction with reference
counting to manage interrupt context lifecycle. This allows both Ethernet
and RDMA EQs to dynamically acquire dedicated or shared MSI-X vectors at
vPort creation time rather than pre-allocating all vectors at probe time.

This series touches both the net and RDMA MANA drivers and is intended
to go through the net-next tree. The patches are available on a shared
branch for both netdev and RDMA maintainers to review.

The following changes since commit 73d587ae684d176fac9db94173f77d78a794ea4f:

  net: ethtool: fix missing closing paren in rings_reply_size() (2026-05-11 18:42:25 -0700)

are available in the Git repository at:

  https://github.com/longlimsft/linux.git tags/mana-eq-msi-v9

for you to fetch changes up to 8249f52c3a065d92d24f27ab12c0b4d197ba14c4:

  RDMA/mana_ib: Allocate interrupt contexts on EQs

Changes in v9:
- RSS QPs now take a vport reference via pd->vport_use_count to ensure
  EQs outlive all QP consumers. EQs are only destroyed when the last
  QP (raw or RSS) on the PD releases its reference (patch 1)
- Serialize mana_set_channels() against RDMA vport configuration via
  apc->vport_mutex when the port is down. When the port is up, Ethernet
  owns the vport exclusively so no locking is needed (patch 1)
- Change WARN_ON(apc->eqs) to bail out with -EEXIST to prevent
  leaking prior EQ array if invariant is violated (patch 1)
- Only commit pd->tx_shortform_allowed and pd->tx_vp_offset after
  mana_create_eq() succeeds (patch 1)
- Reset gc->msi_sharing at the top of mana_gd_query_max_resources()
  so it is recomputed from current hardware state on resume (patch 2)
- Fix reverse Christmas tree variable declaration ordering (patches
  1, 3, 5)

Changes in v8:
- Fix comment to reference per-vPort queue count instead of
  gc->max_num_queues (patch 2)
- Remove duplicate irq_update_affinity_hint() calls from error paths
  and mana_gd_remove_irqs(); the clearing is now centralized in
  mana_gd_put_gic() (patch 4)
- Note the IRQ name change (mana_q -> mana_msi) in the commit
  message (patch 4)
- Remove dead conditional write to spec.eq.msix_index (patch 5)
- Document GIC ownership contract and msix_index invariant change
  in commit message (patch 5)
- Populate eq.irq on RDMA EQs for consistency with the Ethernet
  path (patch 6)
- Document BIT(6) relocation and capability flag semantics in
  commit message (patch 6)
- Fix checkpatch --strict alignment and line length warnings

Changes in v7:
- Use rounddown_pow_of_two() instead of roundup_pow_of_two() when
  computing per-vPort queue count to avoid unnecessarily forcing shared
  MSI-X mode (patch 2)
- Call mana_gd_setup_remaining_irqs() unconditionally to ensure
  irq_contexts are populated in both dedicated and shared MSI-X modes,
  fixing bisectability between patches 2 and 5 (patch 2)
- Guard ibdev_dbg() in mana_ib_cfg_vport() with error check so the
  vport handle is not logged on the failure path (patch 1)
- Use cached gic->irq instead of pci_irq_vector() lookup in
  mana_gd_put_gic() for consistency with the allocation path (patch 3)
- Fix unsigned int* to int* pointer type mismatch when calling
  mana_gd_get_gic() by using a local int variable for the MSI index
  (patches 5, 6)

Changes in v6:
- Rebased on net-next/main (v7.1-rc1)

Changes in v5:
- Rebased on net-next/main

Changes in v4:
- Rebased on net-next/main 7.0-rc4
- Patch 2: Use MANA_DEF_NUM_QUEUES instead of hardcoded 16 for
  max_num_queues clamping
- Patch 3: Track dyn_msix in GIC context instead of re-checking
  pci_msix_can_alloc_dyn() on each call; improved remove_irqs iteration
  to skip unallocated entries

Changes in v3:
- Rebased on net-next/main
- Patch 1: Added NULL check for mpc->eqs in mana_ib_create_qp_rss() to
  prevent NULL pointer dereference when RSS QP is created before a raw QP
  has configured the vport and allocated EQs

Changes in v2:
- Rebased on net-next/main (adapted to kzalloc_objs/kzalloc_obj macros,
  new GDMA_DRV_CAP_FLAG definitions)
- Patch 2: Fixed misleading comment for max_num_queues vs
  max_num_queues_vport in gdma.h
- Patch 3: Fixed spelling typo in gdma_main.c ("difference" -> "different")

Long Li (6):
  net: mana: Create separate EQs for each vPort
  net: mana: Query device capabilities and configure MSI-X sharing for
    EQs
  net: mana: Introduce GIC context with refcounting for interrupt
    management
  net: mana: Use GIC functions to allocate global EQs
  net: mana: Allocate interrupt context for each EQ when creating vPort
  RDMA/mana_ib: Allocate interrupt contexts on EQs

 drivers/infiniband/hw/mana/main.c             |  67 +++-
 drivers/infiniband/hw/mana/qp.c               |  37 +-
 .../net/ethernet/microsoft/mana/gdma_main.c   | 323 +++++++++++++-----
 drivers/net/ethernet/microsoft/mana/mana_en.c | 170 +++++----
 .../ethernet/microsoft/mana/mana_ethtool.c    |  27 +-
 include/net/mana/gdma.h                       |  33 +-
 include/net/mana/mana.h                       |   7 +-
 7 files changed, 488 insertions(+), 176 deletions(-)

-- 
2.43.0