Revert "drm/amdgpu: support userptr cross VMAs case with HMM"

This reverts commit 5aeaccca30023c00d982dfa7bfd25b384523460a.

This depends on an HMM fix which is not upstream yet.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index c14198737dcdf852bf9afda605df98ba7c0ff6c0..c1240bf243ba69ab8749ad97fbe62c9deefac944 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -711,8 +711,7 @@ struct amdgpu_ttm_tt {
        struct task_struct      *usertask;
        uint32_t                userflags;
 #if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR)
-       struct hmm_range        *ranges;
-       int                     nr_ranges;
+       struct hmm_range        range;
 #endif
 };
 
@@ -724,108 +723,62 @@ struct amdgpu_ttm_tt {
  * once afterwards to stop HMM tracking
  */
 #if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR)
-
-/* Support Userptr pages cross max 16 vmas */
-#define MAX_NR_VMAS    (16)
-
 int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages)
 {
        struct amdgpu_ttm_tt *gtt = (void *)ttm;
        struct mm_struct *mm = gtt->usertask->mm;
-       unsigned long start = gtt->userptr;
-       unsigned long end = start + ttm->num_pages * PAGE_SIZE;
-       struct hmm_range *ranges;
-       struct vm_area_struct *vma = NULL, *vmas[MAX_NR_VMAS];
-       uint64_t *pfns, f;
-       int r = 0, i, nr_pages;
+       unsigned long end = gtt->userptr + ttm->num_pages * PAGE_SIZE;
+       struct hmm_range *range = &gtt->range;
+       int r = 0, i;
 
        if (!mm) /* Happens during process shutdown */
                return -ESRCH;
 
-       down_read(&mm->mmap_sem);
-
-       /* user pages may cross multiple VMAs */
-       gtt->nr_ranges = 0;
-       do {
-               unsigned long vm_start;
-
-               if (gtt->nr_ranges >= MAX_NR_VMAS) {
-                       DRM_ERROR("Too many VMAs in userptr range\n");
-                       r = -EFAULT;
-                       goto out;
-               }
-
-               vm_start = vma ? vma->vm_end : start;
-               vma = find_vma(mm, vm_start);
-               if (unlikely(!vma || vm_start < vma->vm_start)) {
-                       r = -EFAULT;
-                       goto out;
-               }
-               vmas[gtt->nr_ranges++] = vma;
-       } while (end > vma->vm_end);
+       amdgpu_hmm_init_range(range);
 
-       DRM_DEBUG_DRIVER("0x%lx nr_ranges %d pages 0x%lx\n",
-               start, gtt->nr_ranges, ttm->num_pages);
+       down_read(&mm->mmap_sem);
 
-       if (unlikely((gtt->userflags & AMDGPU_GEM_USERPTR_ANONONLY) &&
-               vmas[0]->vm_file)) {
+       range->vma = find_vma(mm, gtt->userptr);
+       if (!range_in_vma(range->vma, gtt->userptr, end))
+               r = -EFAULT;
+       else if ((gtt->userflags & AMDGPU_GEM_USERPTR_ANONONLY) &&
+               range->vma->vm_file)
                r = -EPERM;
+       if (r)
                goto out;
-       }
 
-       ranges = kvmalloc_array(gtt->nr_ranges, sizeof(*ranges), GFP_KERNEL);
-       if (unlikely(!ranges)) {
+       range->pfns = kvmalloc_array(ttm->num_pages, sizeof(uint64_t),
+                                    GFP_KERNEL);
+       if (range->pfns == NULL) {
                r = -ENOMEM;
                goto out;
        }
+       range->start = gtt->userptr;
+       range->end = end;
 
-       pfns = kvmalloc_array(ttm->num_pages, sizeof(*pfns), GFP_KERNEL);
-       if (unlikely(!pfns)) {
-               r = -ENOMEM;
-               goto out_free_ranges;
-       }
-
-       for (i = 0; i < gtt->nr_ranges; i++)
-               amdgpu_hmm_init_range(&ranges[i]);
-
-       f = ranges[0].flags[HMM_PFN_VALID];
-       f |= amdgpu_ttm_tt_is_readonly(ttm) ?
-                               0 : ranges[0].flags[HMM_PFN_WRITE];
-       memset64(pfns, f, ttm->num_pages);
-
-       for (nr_pages = 0, i = 0; i < gtt->nr_ranges; i++) {
-               ranges[i].vma = vmas[i];
-               ranges[i].start = max(start, vmas[i]->vm_start);
-               ranges[i].end = min(end, vmas[i]->vm_end);
-               ranges[i].pfns = pfns + nr_pages;
-               nr_pages += (ranges[i].end - ranges[i].start) / PAGE_SIZE;
-
-               r = hmm_vma_fault(&ranges[i], true);
-               if (unlikely(r))
-                       break;
-       }
-       if (unlikely(r)) {
-               while (i--)
-                       hmm_vma_range_done(&ranges[i]);
+       range->pfns[0] = range->flags[HMM_PFN_VALID];
+       range->pfns[0] |= amdgpu_ttm_tt_is_readonly(ttm) ?
+                               0 : range->flags[HMM_PFN_WRITE];
+       for (i = 1; i < ttm->num_pages; i++)
+               range->pfns[i] = range->pfns[0];
 
+       /* This may trigger page table update */
+       r = hmm_vma_fault(range, true);
+       if (r)
                goto out_free_pfns;
-       }
 
        up_read(&mm->mmap_sem);
 
        for (i = 0; i < ttm->num_pages; i++)
-               pages[i] = hmm_pfn_to_page(&ranges[0], pfns[i]);
-       gtt->ranges = ranges;
+               pages[i] = hmm_pfn_to_page(range, range->pfns[i]);
 
        return 0;
 
 out_free_pfns:
-       kvfree(pfns);
-out_free_ranges:
-       kvfree(ranges);
+       kvfree(range->pfns);
+       range->pfns = NULL;
 out:
        up_read(&mm->mmap_sem);
-
        return r;
 }
 
@@ -839,23 +792,15 @@ bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm)
 {
        struct amdgpu_ttm_tt *gtt = (void *)ttm;
        bool r = false;
-       int i;
 
        if (!gtt || !gtt->userptr)
                return false;
 
-       DRM_DEBUG_DRIVER("user_pages_done 0x%llx nr_ranges %d pages 0x%lx\n",
-               gtt->userptr, gtt->nr_ranges, ttm->num_pages);
-
-       WARN_ONCE(!gtt->ranges || !gtt->ranges[0].pfns,
-               "No user pages to check\n");
-
-       if (gtt->ranges) {
-               for (i = 0; i < gtt->nr_ranges; i++)
-                       r |= hmm_vma_range_done(&gtt->ranges[i]);
-               kvfree(gtt->ranges[0].pfns);
-               kvfree(gtt->ranges);
-               gtt->ranges = NULL;
+       WARN_ONCE(!gtt->range.pfns, "No user pages to check\n");
+       if (gtt->range.pfns) {
+               r = hmm_vma_range_done(&gtt->range);
+               kvfree(gtt->range.pfns);
+               gtt->range.pfns = NULL;
        }
 
        return r;
@@ -939,9 +884,8 @@ static void amdgpu_ttm_tt_unpin_userptr(struct ttm_tt *ttm)
        sg_free_table(ttm->sg);
 
 #if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR)
-       if (gtt->ranges &&
-           ttm->pages[0] == hmm_pfn_to_page(&gtt->ranges[0],
-                                            gtt->ranges[0].pfns[0]))
+       if (gtt->range.pfns &&
+           ttm->pages[0] == hmm_pfn_to_page(&gtt->range, gtt->range.pfns[0]))
                WARN_ONCE(1, "Missing get_user_page_done\n");
 #endif
 }