[PATCH for-next v4 0/5] RDMA/erdma: Support non-contiguous kernel queue buffers

[Cheng Xu <chengyou@linux.alibaba.com>]

Hi,

This small patchset introduces support for non-contiguous kernel queue
buffers. Kernel QP and CQ buffers currently use a single coherent DMA
allocation, which can fail for large queues when memory is fragmented.
To address this, we allocate page-sized coherent buffers and describe
them with the existing MTT.

- #1 unwinds kernel QP initialization failures explicitly.
- #2 adds support for non-contiguous kernel QP buffers.
- #3 adds support for non-contiguous kernel CQ buffers.
- #4 unifies userspace and kernel space queue buffer management.
- #5 moves kernel QP helpers after the shared memory helpers.

Changes from v3:
- Address Sashiko automated review findings:
  - Keep the CPU and DMA addresses returned by dma_alloc_coherent() instead
    of deriving a virtual address through scatterlist helpers.
  - Sync continuous MTTs after populating their entries.
  - Keep DMA MRs and MTT-only FRMRs outside queue buffer backing cleanup.

Changes from v2:
- Add explicit resource unwinding for kernel QP initialization.
- Use struct scatterlist for kernel queue buffer pages.
- Make memory cleanup operate only on initialized backing memory.
- Return -ENOMEM when a kernel QP doorbell record allocation fails.

Changes from v1:
- Fix formatting issues.

Thanks,
Cheng Xu

Cheng Xu (5):
  RDMA/erdma: Unwind kernel QP initialization failures
  RDMA/erdma: Support non-contiguous kernel QP buffers
  RDMA/erdma: Support non-contiguous kernel CQ buffers
  RDMA/erdma: Unify userspace and kernel queue buffer management
  RDMA/erdma: Move kernel QP helpers after memory helpers

 drivers/infiniband/hw/erdma/erdma_cq.c    |  18 +-
 drivers/infiniband/hw/erdma/erdma_qp.c    |  38 +-
 drivers/infiniband/hw/erdma/erdma_verbs.c | 569 ++++++++++++----------
 drivers/infiniband/hw/erdma/erdma_verbs.h |  65 ++-
 4 files changed, 404 insertions(+), 286 deletions(-)

-- 
2.31.1