diff options
Diffstat (limited to 'drivers/infiniband/core/umem.c')
-rw-r--r-- | drivers/infiniband/core/umem.c | 179 |
1 files changed, 138 insertions, 41 deletions
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index fe5551562dbc..0a23048db523 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -37,27 +37,23 @@ #include <linux/sched/signal.h> #include <linux/sched/mm.h> #include <linux/export.h> -#include <linux/hugetlb.h> #include <linux/slab.h> +#include <linux/pagemap.h> #include <rdma/ib_umem_odp.h> #include "uverbs.h" - static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty) { - struct scatterlist *sg; + struct sg_page_iter sg_iter; struct page *page; - int i; if (umem->nmap > 0) - ib_dma_unmap_sg(dev, umem->sg_head.sgl, - umem->npages, + ib_dma_unmap_sg(dev, umem->sg_head.sgl, umem->sg_nents, DMA_BIDIRECTIONAL); - for_each_sg(umem->sg_head.sgl, sg, umem->npages, i) { - - page = sg_page(sg); + for_each_sg_page(umem->sg_head.sgl, &sg_iter, umem->sg_nents, 0) { + page = sg_page_iter_page(&sg_iter); if (!PageDirty(page) && umem->writable && dirty) set_page_dirty_lock(page); put_page(page); @@ -66,6 +62,124 @@ static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int d sg_free_table(&umem->sg_head); } +/* ib_umem_add_sg_table - Add N contiguous pages to scatter table + * + * sg: current scatterlist entry + * page_list: array of npage struct page pointers + * npages: number of pages in page_list + * max_seg_sz: maximum segment size in bytes + * nents: [out] number of entries in the scatterlist + * + * Return new end of scatterlist + */ +static struct scatterlist *ib_umem_add_sg_table(struct scatterlist *sg, + struct page **page_list, + unsigned long npages, + unsigned int max_seg_sz, + int *nents) +{ + unsigned long first_pfn; + unsigned long i = 0; + bool update_cur_sg = false; + bool first = !sg_page(sg); + + /* Check if new page_list is contiguous with end of previous page_list. + * sg->length here is a multiple of PAGE_SIZE and sg->offset is 0. + */ + if (!first && (page_to_pfn(sg_page(sg)) + (sg->length >> PAGE_SHIFT) == + page_to_pfn(page_list[0]))) + update_cur_sg = true; + + while (i != npages) { + unsigned long len; + struct page *first_page = page_list[i]; + + first_pfn = page_to_pfn(first_page); + + /* Compute the number of contiguous pages we have starting + * at i + */ + for (len = 0; i != npages && + first_pfn + len == page_to_pfn(page_list[i]) && + len < (max_seg_sz >> PAGE_SHIFT); + len++) + i++; + + /* Squash N contiguous pages from page_list into current sge */ + if (update_cur_sg) { + if ((max_seg_sz - sg->length) >= (len << PAGE_SHIFT)) { + sg_set_page(sg, sg_page(sg), + sg->length + (len << PAGE_SHIFT), + 0); + update_cur_sg = false; + continue; + } + update_cur_sg = false; + } + + /* Squash N contiguous pages into next sge or first sge */ + if (!first) + sg = sg_next(sg); + + (*nents)++; + sg_set_page(sg, first_page, len << PAGE_SHIFT, 0); + first = false; + } + + return sg; +} + +/** + * ib_umem_find_best_pgsz - Find best HW page size to use for this MR + * + * @umem: umem struct + * @pgsz_bitmap: bitmap of HW supported page sizes + * @virt: IOVA + * + * This helper is intended for HW that support multiple page + * sizes but can do only a single page size in an MR. + * + * Returns 0 if the umem requires page sizes not supported by + * the driver to be mapped. Drivers always supporting PAGE_SIZE + * or smaller will never see a 0 result. + */ +unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem, + unsigned long pgsz_bitmap, + unsigned long virt) +{ + struct scatterlist *sg; + unsigned int best_pg_bit; + unsigned long va, pgoff; + dma_addr_t mask; + int i; + + /* At minimum, drivers must support PAGE_SIZE or smaller */ + if (WARN_ON(!(pgsz_bitmap & GENMASK(PAGE_SHIFT, 0)))) + return 0; + + va = virt; + /* max page size not to exceed MR length */ + mask = roundup_pow_of_two(umem->length); + /* offset into first SGL */ + pgoff = umem->address & ~PAGE_MASK; + + for_each_sg(umem->sg_head.sgl, sg, umem->nmap, i) { + /* Walk SGL and reduce max page size if VA/PA bits differ + * for any address. + */ + mask |= (sg_dma_address(sg) + pgoff) ^ va; + if (i && i != (umem->nmap - 1)) + /* restrict by length as well for interior SGEs */ + mask |= sg_dma_len(sg); + va += sg_dma_len(sg) - pgoff; + pgoff = 0; + } + best_pg_bit = rdma_find_pg_bit(mask, pgsz_bitmap); + + return BIT_ULL(best_pg_bit); +} +EXPORT_SYMBOL(ib_umem_find_best_pgsz); + /** * ib_umem_get - Pin and DMA map userspace memory. * @@ -84,16 +198,14 @@ struct ib_umem *ib_umem_get(struct ib_udata *udata, unsigned long addr, struct ib_ucontext *context; struct ib_umem *umem; struct page **page_list; - struct vm_area_struct **vma_list; unsigned long lock_limit; unsigned long new_pinned; unsigned long cur_base; struct mm_struct *mm; unsigned long npages; int ret; - int i; unsigned long dma_attrs = 0; - struct scatterlist *sg, *sg_list_start; + struct scatterlist *sg; unsigned int gup_flags = FOLL_WRITE; if (!udata) @@ -138,29 +250,23 @@ struct ib_umem *ib_umem_get(struct ib_udata *udata, unsigned long addr, mmgrab(mm); if (access & IB_ACCESS_ON_DEMAND) { + if (WARN_ON_ONCE(!context->invalidate_range)) { + ret = -EINVAL; + goto umem_kfree; + } + ret = ib_umem_odp_get(to_ib_umem_odp(umem), access); if (ret) goto umem_kfree; return umem; } - /* We assume the memory is from hugetlb until proved otherwise */ - umem->hugetlb = 1; - page_list = (struct page **) __get_free_page(GFP_KERNEL); if (!page_list) { ret = -ENOMEM; goto umem_kfree; } - /* - * if we can't alloc the vma_list, it's not so bad; - * just assume the memory is not hugetlb memory - */ - vma_list = (struct vm_area_struct **) __get_free_page(GFP_KERNEL); - if (!vma_list) - umem->hugetlb = 0; - npages = ib_umem_num_pages(umem); if (npages == 0 || npages > UINT_MAX) { ret = -EINVAL; @@ -185,41 +291,34 @@ struct ib_umem *ib_umem_get(struct ib_udata *udata, unsigned long addr, if (!umem->writable) gup_flags |= FOLL_FORCE; - sg_list_start = umem->sg_head.sgl; + sg = umem->sg_head.sgl; while (npages) { down_read(&mm->mmap_sem); ret = get_user_pages_longterm(cur_base, min_t(unsigned long, npages, PAGE_SIZE / sizeof (struct page *)), - gup_flags, page_list, vma_list); + gup_flags, page_list, NULL); if (ret < 0) { up_read(&mm->mmap_sem); goto umem_release; } - umem->npages += ret; cur_base += ret * PAGE_SIZE; npages -= ret; - /* Continue to hold the mmap_sem as vma_list access - * needs to be protected. - */ - for_each_sg(sg_list_start, sg, ret, i) { - if (vma_list && !is_vm_hugetlb_page(vma_list[i])) - umem->hugetlb = 0; + sg = ib_umem_add_sg_table(sg, page_list, ret, + dma_get_max_seg_size(context->device->dma_device), + &umem->sg_nents); - sg_set_page(sg, page_list[i], PAGE_SIZE, 0); - } up_read(&mm->mmap_sem); - - /* preparing for next loop */ - sg_list_start = sg; } + sg_mark_end(sg); + umem->nmap = ib_dma_map_sg_attrs(context->device, umem->sg_head.sgl, - umem->npages, + umem->sg_nents, DMA_BIDIRECTIONAL, dma_attrs); @@ -236,8 +335,6 @@ umem_release: vma: atomic64_sub(ib_umem_num_pages(umem), &mm->pinned_vm); out: - if (vma_list) - free_page((unsigned long) vma_list); free_page((unsigned long) page_list); umem_kfree: if (ret) { @@ -315,7 +412,7 @@ int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset, return -EINVAL; } - ret = sg_pcopy_to_buffer(umem->sg_head.sgl, umem->npages, dst, length, + ret = sg_pcopy_to_buffer(umem->sg_head.sgl, umem->sg_nents, dst, length, offset + ib_umem_offset(umem)); if (ret < 0) |