From: "Saleem, Shiraz" <shiraz.saleem@xxxxxxxxx> This patch set is aiming to allow drivers to leverage a new DMA block iterator to get contiguous aligned memory blocks within their HW supported page sizes. The motivation for this work comes from the discussion in [1]. The first patch introduces a new umem API that allows drivers to find a best supported page size to use for the MR, from a bitmap of HW supported page sizes. The second patch introduces a new DMA block iterator that returns allows drivers to get aligned DMA addresses within a supplied best page size. The third patch and fouth patch removes the dependency of i40iw and bnxt_re drivers on the hugetlb flag. The new core APIs are called in these drivers to get huge page size aligned addresses if the MR is backed by huge pages. The fifth patch removes the hugetlb flag from IB core. The sixth patch extends the DMA block itertaor for HW that can support mixed block sizes. This patch is untested. [1] https://patchwork.kernel.org/patch/10499753/ RFC-->v0: --------- * Add to scatter table by iterating a limited sized page list. * Updated driver call sites to use the for_each_sg_page iterator variant where applicable. * Tweaked algorithm in ib_umem_find_single_pg_size and ib_umem_next_phys_iter to ignore alignment of the start of first SGE and end of the last SGE. * Simplified ib_umem_find_single_pg_size on offset alignments checks for user-space virtual and physical buffer. * Updated ib_umem_start_phys_iter to do some pre-computation for the non-mixed page support case. * Updated bnxt_re driver to use the new core APIs and remove its dependency on the huge tlb flag. * Fixed a bug in computation of sg_phys_iter->phyaddr in ib_umem_next_phys_iter. * Drop hugetlb flag usage from RDMA subsystem. * Rebased on top of for-next. v0-->v1: -------- * Remove the patches that update driver to use for_each_sg_page variant to iterate in the SGE. This is sent as a seperate series using the for_each_sg_dma_page variant. * Tweak ib_umem_add_sg_table API defintion based on maintainer feedback. * Cache number of scatterlist entries in umem. * Update function headers for ib_umem_find_single_pg_size and ib_umem_next_phys_iter. * Add sanity check on supported_pgsz in ib_umem_find_single_pg_size. v1-->v2: -------- *Removed page combining patch as it was sent stand alone. *__fls on pgsz_bitmap as opposed to fls64 since it's an unsigned long. *rename ib_umem_find_pg_bit() --> rdma_find_pg_bit() and moved to ib_verbs.h *rename ib_umem_find_single_pg_size() --> ib_umem_find_best_pgsz() *New flag IB_UMEM_VA_BASED_OFFSET for ib_umem_find_best_pgsz API for HW that uses least significant bits of VA to indicate start offset into DMA list. *rdma_find_pg_bit() logic is re-written and simplified. It can support input of 0 or 1 dma addr cases. *ib_umem_find_best_pgsz() optimized to be less computationally expensive running rdma_find_pg_bit() only once. *rdma_for_each_block() is the new re-designed DMA block iterator which is more in line with for_each_sg_dma_page()iterator. *rdma_find_mixed_pg_bit() logic for interior SGE's accounting for start and end dma address. *remove i40iw specific enums for supported page size *remove vma_list form ib_umem_get() v2-->v3: --------- *Check VA/PA bits misalignment to restrict max page size for all SGL address in ib_umem_find_best_pgsz() *ib_umem_find_best_pgsz() extended to work with any IOVA *IB_UMEM_VA_BASED_OFFSET flag removed. *DMA block iterator API split into 2 patches. One for HW that supports single blocks and second which extends the API to support HW that can do mixed block sizes. Shiraz Saleem (6): RDMA/umem: Add API to find best driver supported page size in an MR RDMA/verbs: Add a DMA iterator to return aligned contiguous memory blocks RDMA/i40iw: Use core helpers to get aligned DMA address within a supported page size RDMA/bnxt_re: Use core helpers to get aligned DMA address RDMA/umem: Remove hugetlb flag RDMA/verbs: Extend DMA block iterator support for mixed block sizes drivers/infiniband/core/umem.c | 77 +++++++++++++++++++---------- drivers/infiniband/core/umem_odp.c | 3 -- drivers/infiniband/core/verbs.c | 68 ++++++++++++++++++++++++++ drivers/infiniband/hw/bnxt_re/ib_verbs.c | 27 ++++------- drivers/infiniband/hw/i40iw/i40iw_verbs.c | 46 +++--------------- drivers/infiniband/hw/i40iw/i40iw_verbs.h | 3 +- include/rdma/ib_umem.h | 10 +++- include/rdma/ib_verbs.h | 81 +++++++++++++++++++++++++++++++ 8 files changed, 228 insertions(+), 87 deletions(-) -- 1.8.3.1
