On Mon, May 06, 2019 at 08:53:31AM -0500, Shiraz Saleem wrote: > 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 Applied to for-next except for: > RDMA/verbs: Extend DMA block iterator support for mixed block sizes Thanks, Jason
