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This adds: - get_user_pages_batch(): gets user pages for a single range within a batch allocation using HMM - set_user_pages_batch(): populates TTM page array from multiple HMM ranges Signed-off-by: Honglei Huang --- .../gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 54 +++++++++++++++++++ 1 file changed, 54 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c index af6db20de..7aca1868d 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c @@ -1200,6 +1200,60 @@ static const struct mmu_interval_notifier_ops amdgpu_amdkfd_hsa_batch_ops = { .invalidate = amdgpu_amdkfd_invalidate_userptr_batch, }; +static int get_user_pages_batch(struct mm_struct *mm, + struct kgd_mem *mem, + struct user_range_info *range, + struct hmm_range **range_hmm, bool readonly) +{ + struct vm_area_struct *vma; + int r = 0; + + *range_hmm = NULL; + + if (!mmget_not_zero(mm)) + return -ESRCH; + + mmap_read_lock(mm); + vma = vma_lookup(mm, range->start); + if (unlikely(!vma)) { + r = -EFAULT; + goto out_unlock; + } + + r = amdgpu_hmm_range_get_pages(&mem->batch_notifier, range->start, + range->size >> PAGE_SHIFT, readonly, + NULL, range_hmm); + +out_unlock: + mmap_read_unlock(mm); + mmput(mm); + return r; +} + +static int set_user_pages_batch(struct ttm_tt *ttm, + struct user_range_info *ranges, + uint32_t nranges) +{ + uint32_t i, j, k = 0, range_npfns; + + for (i = 0; i < nranges; ++i) { + if (!ranges[i].range || !ranges[i].range->hmm_pfns) + return -EINVAL; + + range_npfns = (ranges[i].range->end - ranges[i].range->start) >> + PAGE_SHIFT; + + if (k + range_npfns > ttm->num_pages) + return -EOVERFLOW; + + for (j = 0; j < range_npfns; ++j) + ttm->pages[k++] = + hmm_pfn_to_page(ranges[i].range->hmm_pfns[j]); + } + + return 0; +} + /* Reserving a BO and its page table BOs must happen atomically to * avoid deadlocks. Some operations update multiple VMs at once. Track * all the reservation info in a context structure. Optionally a sync -- 2.34.1