[00/14] RDMA: Improve use of umem in DMA drivers

Message

Jason Gunthorpe Sept. 2, 2020, 12:43 a.m. UTC

Most RDMA drivers rely on a linear table of DMA addresses organized in
some device specific page size.

For a while now the core code has had the rdma_for_each_block() SG
iterator to help break a umem into DMA blocks for use in the device lists.

Improve on this by adding rdma_umem_for_each_dma_block(),
ib_umem_dma_offset() and ib_umem_num_dma_blocks().

Replace open codings, or calls to fixed PAGE_SIZE APIs, in most of the
drivers with one of the above APIs.

Get rid of the really weird and duplicative ib_umem_page_count().

Fix two problems with ib_umem_find_best_pgsz().

At this point many of the driver have a clear path to call
ib_umem_find_best_pgsz() and replace hardcoded PAGE_SIZE or PAGE_SHIFT
values when constructing their DMA lists.

This is the first series in an effort to modernize the umem usage in all
the DMA drivers.

Jason Gunthorpe (14):
  RDMA/umem: Fix ib_umem_find_best_pgsz() for mappings that cross a page
    boundary
  RDMA/umem: Prevent small pages from being returned by
    ib_umem_find_best_pgsz()
  RDMA/umem: Use simpler logic for ib_umem_find_best_pgsz()
  RDMA/umem: Add rdma_umem_for_each_dma_block()
  RDMA/umem: Replace for_each_sg_dma_page with
    rdma_umem_for_each_dma_block
  RDMA/umem: Split ib_umem_num_pages() into ib_umem_num_dma_blocks()
  RDMA/qedr: Use rdma_umem_for_each_dma_block() instead of open-coding
  RDMA/qedr: Use ib_umem_num_dma_blocks() instead of
    ib_umem_page_count()
  RDMA/bnxt: Do not use ib_umem_page_count() or ib_umem_num_pages()
  RDMA/hns: Use ib_umem_num_dma_blocks() instead of opencoding
  RDMA/ocrdma: Use ib_umem_num_dma_blocks() instead of
    ib_umem_page_count()
  RDMA/pvrdma: Use ib_umem_num_dma_blocks() instead of
    ib_umem_page_count()
  RDMA/mlx5: Use ib_umem_num_dma_blocks()
  RDMA/umem: Rename ib_umem_offset() to ib_umem_dma_offset()

 .clang-format                                 |  1 +
 drivers/infiniband/core/umem.c                | 41 ++++++-----
 drivers/infiniband/hw/bnxt_re/ib_verbs.c      | 72 +++++++------------
 drivers/infiniband/hw/cxgb4/mem.c             |  8 +--
 drivers/infiniband/hw/efa/efa_verbs.c         |  3 +-
 drivers/infiniband/hw/hns/hns_roce_alloc.c    |  3 +-
 drivers/infiniband/hw/hns/hns_roce_mr.c       | 49 +++++--------
 drivers/infiniband/hw/i40iw/i40iw_verbs.c     |  3 +-
 drivers/infiniband/hw/mlx4/cq.c               |  8 +--
 drivers/infiniband/hw/mlx4/mlx4_ib.h          |  3 +-
 drivers/infiniband/hw/mlx4/mr.c               | 14 ++--
 drivers/infiniband/hw/mlx4/qp.c               | 17 ++---
 drivers/infiniband/hw/mlx4/srq.c              |  5 +-
 drivers/infiniband/hw/mlx5/mem.c              |  5 +-
 drivers/infiniband/hw/mthca/mthca_provider.c  |  8 +--
 drivers/infiniband/hw/ocrdma/ocrdma_verbs.c   | 26 +++----
 drivers/infiniband/hw/qedr/verbs.c            | 50 ++++++-------
 drivers/infiniband/hw/vmw_pvrdma/pvrdma_cq.c  |  2 +-
 .../infiniband/hw/vmw_pvrdma/pvrdma_misc.c    |  9 ++-
 drivers/infiniband/hw/vmw_pvrdma/pvrdma_mr.c  |  2 +-
 drivers/infiniband/hw/vmw_pvrdma/pvrdma_qp.c  |  6 +-
 drivers/infiniband/hw/vmw_pvrdma/pvrdma_srq.c |  2 +-
 drivers/infiniband/sw/rdmavt/mr.c             |  2 +-
 drivers/infiniband/sw/rxe/rxe_mr.c            |  2 +-
 include/rdma/ib_umem.h                        | 45 +++++++++---
 include/rdma/ib_verbs.h                       | 24 -------
 26 files changed, 184 insertions(+), 226 deletions(-)

Comments

Gal Pressman Sept. 2, 2020, 9:09 a.m. UTC | #1

On 02/09/2020 3:43, Jason Gunthorpe wrote:
> This is the first series in an effort to modernize the umem usage in all
> the DMA drivers.

Can you please explain what are the next steps? What's the final goal?

Jason Gunthorpe Sept. 2, 2020, noon UTC | #2

On Wed, Sep 02, 2020 at 12:09:41PM +0300, Gal Pressman wrote:
> On 02/09/2020 3:43, Jason Gunthorpe wrote:
> > This is the first series in an effort to modernize the umem usage in all
> > the DMA drivers.
> 
> Can you please explain what are the next steps? What's the final goal?

DMA drivers should not touch the umem sgl directly

Jason