From 66c45500bfdc6a7f1c143767dfbc8fc8f9435e73 Mon Sep 17 00:00:00 2001 From: Philip Yang Date: Wed, 29 May 2019 09:52:16 -0400 Subject: [PATCH] drm/amdgpu: use new HMM APIs and helpers HMM provides new APIs and helps in kernel 5.2-rc1 to simplify driver path. The old hmm APIs are deprecated and will be removed in future. Below are changes in driver: 1. Change hmm_vma_fault to hmm_range_register and hmm_range_fault which supports range with multiple vmas, remove the multiple vmas handle path and data structure. 2. Change hmm_vma_range_done to hmm_range_unregister. 3. Use default flags to avoid pre-fill pfn arrays. 4. Use new hmm_device_ helpers. Signed-off-by: Philip Yang Reviewed-by: Felix Kuehling Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 1 - drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 152 +++++++++++------------- 2 files changed, 68 insertions(+), 85 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c index 41ccee49a224..e0bb47ce570b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c @@ -519,7 +519,6 @@ void amdgpu_hmm_init_range(struct hmm_range *range) range->flags = hmm_range_flags; range->values = hmm_range_values; range->pfn_shift = PAGE_SHIFT; - range->pfns = NULL; INIT_LIST_HEAD(&range->list); } } diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 7138dc1dd1f4..2778ff63d97d 100644 --- 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 }; @@ -725,57 +724,36 @@ struct amdgpu_ttm_tt { */ #if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR) -/* Support Userptr pages cross max 16 vmas */ -#define MAX_NR_VMAS (16) +#define MAX_RETRY_HMM_RANGE_FAULT 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 vm_area_struct *vma = NULL, *vmas[MAX_NR_VMAS]; - struct hmm_range *ranges; - unsigned long nr_pages, i; - uint64_t *pfns, f; + struct vm_area_struct *vma; + struct hmm_range *range; + unsigned long i; + uint64_t *pfns; + int retry = 0; int r = 0; 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); - - DRM_DEBUG_DRIVER("0x%lx nr_ranges %d pages 0x%lx\n", - start, gtt->nr_ranges, ttm->num_pages); - + vma = find_vma(mm, start); + if (unlikely(!vma || start < vma->vm_start)) { + r = -EFAULT; + goto out; + } if (unlikely((gtt->userflags & AMDGPU_GEM_USERPTR_ANONONLY) && - vmas[0]->vm_file)) { + vma->vm_file)) { r = -EPERM; goto out; } - ranges = kvmalloc_array(gtt->nr_ranges, sizeof(*ranges), GFP_KERNEL); - if (unlikely(!ranges)) { + range = kzalloc(sizeof(*range), GFP_KERNEL); + if (unlikely(!range)) { r = -ENOMEM; goto out; } @@ -786,61 +764,67 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages) goto out_free_ranges; } - for (i = 0; i < gtt->nr_ranges; i++) - amdgpu_hmm_init_range(&ranges[i]); + amdgpu_hmm_init_range(range); + range->default_flags = range->flags[HMM_PFN_VALID]; + range->default_flags |= amdgpu_ttm_tt_is_readonly(ttm) ? + 0 : range->flags[HMM_PFN_WRITE]; + range->pfn_flags_mask = 0; + range->pfns = pfns; + hmm_range_register(range, mm, start, + start + ttm->num_pages * PAGE_SIZE, PAGE_SHIFT); - 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); +retry: + /* + * Just wait for range to be valid, safe to ignore return value as we + * will use the return value of hmm_range_fault() below under the + * mmap_sem to ascertain the validity of the range. + */ + hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT); - 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; + down_read(&mm->mmap_sem); - r = hmm_vma_fault(&ranges[i], true); - if (unlikely(r)) - break; - } - if (unlikely(r)) { - while (i--) - hmm_vma_range_done(&ranges[i]); + r = hmm_range_fault(range, true); + if (unlikely(r < 0)) { + if (likely(r == -EAGAIN)) { + /* + * return -EAGAIN, mmap_sem is dropped + */ + if (retry++ < MAX_RETRY_HMM_RANGE_FAULT) + goto retry; + else + pr_err("Retry hmm fault too many times\n"); + } - goto out_free_pfns; + goto out_up_read; } up_read(&mm->mmap_sem); for (i = 0; i < ttm->num_pages; i++) { - pages[i] = hmm_pfn_to_page(&ranges[0], pfns[i]); - if (!pages[i]) { + pages[i] = hmm_device_entry_to_page(range, pfns[i]); + if (unlikely(!pages[i])) { pr_err("Page fault failed for pfn[%lu] = 0x%llx\n", i, pfns[i]); - goto out_invalid_pfn; + r = -ENOMEM; + + goto out_free_pfns; } } - gtt->ranges = ranges; + + gtt->range = range; return 0; +out_up_read: + if (likely(r != -EAGAIN)) + up_read(&mm->mmap_sem); out_free_pfns: + hmm_range_unregister(range); kvfree(pfns); out_free_ranges: - kvfree(ranges); + kfree(range); out: - up_read(&mm->mmap_sem); - return r; - -out_invalid_pfn: - for (i = 0; i < gtt->nr_ranges; i++) - hmm_vma_range_done(&ranges[i]); - kvfree(pfns); - kvfree(ranges); - return -ENOMEM; } /** @@ -853,23 +837,23 @@ 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); + DRM_DEBUG_DRIVER("user_pages_done 0x%llx pages 0x%lx\n", + gtt->userptr, ttm->num_pages); - WARN_ONCE(!gtt->ranges || !gtt->ranges[0].pfns, + WARN_ONCE(!gtt->range || !gtt->range->pfns, "No user pages to check\n"); - if (gtt->ranges) { - for (i = 0; i < gtt->nr_ranges; i++) - r |= hmm_vma_range_done(>t->ranges[i]); - kvfree(gtt->ranges[0].pfns); - kvfree(gtt->ranges); - gtt->ranges = NULL; + if (gtt->range) { + r = hmm_range_valid(gtt->range); + hmm_range_unregister(gtt->range); + + kvfree(gtt->range->pfns); + kfree(gtt->range); + gtt->range = NULL; } return r; @@ -953,9 +937,9 @@ 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(>t->ranges[0], - gtt->ranges[0].pfns[0])) + if (gtt->range && + ttm->pages[0] == hmm_device_entry_to_page(gtt->range, + gtt->range->pfns[0])) WARN_ONCE(1, "Missing get_user_page_done\n"); #endif } -- 2.30.2