Re: [RFC PATCH 1/5] drm/ttm: Refactor num_shared into usage.

[Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>]

On Wed, Jun 1, 2022 at 10:29 AM Christian König
<christian.koenig@amd.com> wrote:
>
> Am 01.06.22 um 10:11 schrieb Bas Nieuwenhuizen:
> > On Wed, Jun 1, 2022 at 10:02 AM Christian König
> > <christian.koenig@amd.com> wrote:
> >> Am 01.06.22 um 02:40 schrieb Bas Nieuwenhuizen:
> >>> So that the driver can set some BOOKKEEP for explicit sync. Maybe
> >>> some of the existing places would already make sense for that, but
> >>> I targeted this for no functional changes.
> >> Well first of all NAK to that one since it will totally break cases
> >> which need to reserve more than one fence slot.
> > TTM already didn't do that? From ttm_execbuf_util.c :
> >
> >>> -             num_fences = min(entry->num_shared, 1u);
> >>> +             num_fences = entry->usage <= DMA_RESV_USAGE_WRITE ? 0u : 1u;
>
> That's doing a min(entry->num_shared, 1u). In other words even when the
> driver requested to reserve no fence we at least reserve at least one.

That would be the case if it was a max, not a min. However, since it
is a min, it only ever resulted in 0 or 1, behavior that we mimic
based on DMA_RESV_USAGE_*.

Nowhere else do we actually use the specific number  assigned to num_shared.

>
> But if the driver requested to reserve more than one then we do reserve
> more than one. That's rather important because both radeon and amdgpu
> need that for their VM updates.
>
> This patch here completely breaks that.
>
> There is already an drm_exec patch set from me on the dri-devel mailing
> list which untangles all of this and deprecates the whole
> ttm_exec_buf_util handling.

Can take a look at your patch, but I believe in pre-patch state this
is a correct non functional change.

>
> Regards,
> Christian.
>
> >> Also as discussed with Daniel we don't want to use BOOKKEEP for implicit
> >> sync. We should instead use READ for that.
> > That is the plan and what we do later in the series, use BOOKKEEP for
> > submissions that don't want to participate in implicit sync?
> >
> > This refactor sets everything to READ or WRITE based on the previous
> > num_shared value, to make sure this patch by itself is not a
> > functional change.
> >
> >> BOOKKEEP is for stuff userspace should never be aware of, e.g. like page
> >> table updates and KFD eviction fences.
> >>
> >> Regards,
> >> Christian.
> >>
> >>> Signed-off-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
> >>> ---
> >>>    drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c  | 10 +++++-----
> >>>    drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c            |  8 +++-----
> >>>    drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c           |  2 +-
> >>>    drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c           |  6 +++---
> >>>    drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c          |  2 +-
> >>>    drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c            |  3 +--
> >>>    drivers/gpu/drm/amd/amdkfd/kfd_svm.c              |  2 +-
> >>>    drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c |  2 +-
> >>>    drivers/gpu/drm/qxl/qxl_release.c                 |  2 +-
> >>>    drivers/gpu/drm/radeon/radeon_cs.c                |  5 +++--
> >>>    drivers/gpu/drm/radeon/radeon_gem.c               |  2 +-
> >>>    drivers/gpu/drm/radeon/radeon_vm.c                |  4 ++--
> >>>    drivers/gpu/drm/ttm/ttm_execbuf_util.c            |  5 ++---
> >>>    drivers/gpu/drm/vmwgfx/vmwgfx_resource.c          | 10 +++++-----
> >>>    drivers/gpu/drm/vmwgfx/vmwgfx_validation.c        |  2 +-
> >>>    include/drm/ttm/ttm_execbuf_util.h                |  3 ++-
> >>>    16 files changed, 33 insertions(+), 35 deletions(-)
> >>>
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> >>> index a4955ef76cfc..a790a089e829 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> >>> @@ -774,7 +774,7 @@ static void add_kgd_mem_to_kfd_bo_list(struct kgd_mem *mem,
> >>>        struct amdgpu_bo *bo = mem->bo;
> >>>
> >>>        INIT_LIST_HEAD(&entry->head);
> >>> -     entry->num_shared = 1;
> >>> +     entry->usage = DMA_RESV_USAGE_READ;
> >>>        entry->bo = &bo->tbo;
> >>>        mutex_lock(&process_info->lock);
> >>>        if (userptr)
> >>> @@ -918,7 +918,7 @@ static int reserve_bo_and_vm(struct kgd_mem *mem,
> >>>
> >>>        ctx->kfd_bo.priority = 0;
> >>>        ctx->kfd_bo.tv.bo = &bo->tbo;
> >>> -     ctx->kfd_bo.tv.num_shared = 1;
> >>> +     ctx->kfd_bo.tv.usage = DMA_RESV_USAGE_READ;
> >>>        list_add(&ctx->kfd_bo.tv.head, &ctx->list);
> >>>
> >>>        amdgpu_vm_get_pd_bo(vm, &ctx->list, &ctx->vm_pd[0]);
> >>> @@ -981,7 +981,7 @@ static int reserve_bo_and_cond_vms(struct kgd_mem *mem,
> >>>
> >>>        ctx->kfd_bo.priority = 0;
> >>>        ctx->kfd_bo.tv.bo = &bo->tbo;
> >>> -     ctx->kfd_bo.tv.num_shared = 1;
> >>> +     ctx->kfd_bo.tv.usage = DMA_RESV_USAGE_READ;
> >>>        list_add(&ctx->kfd_bo.tv.head, &ctx->list);
> >>>
> >>>        i = 0;
> >>> @@ -2218,7 +2218,7 @@ static int validate_invalid_user_pages(struct amdkfd_process_info *process_info)
> >>>                            validate_list.head) {
> >>>                list_add_tail(&mem->resv_list.head, &resv_list);
> >>>                mem->resv_list.bo = mem->validate_list.bo;
> >>> -             mem->resv_list.num_shared = mem->validate_list.num_shared;
> >>> +             mem->resv_list.usage = mem->validate_list.usage;
> >>>        }
> >>>
> >>>        /* Reserve all BOs and page tables for validation */
> >>> @@ -2417,7 +2417,7 @@ int amdgpu_amdkfd_gpuvm_restore_process_bos(void *info, struct dma_fence **ef)
> >>>
> >>>                list_add_tail(&mem->resv_list.head, &ctx.list);
> >>>                mem->resv_list.bo = mem->validate_list.bo;
> >>> -             mem->resv_list.num_shared = mem->validate_list.num_shared;
> >>> +             mem->resv_list.usage = mem->validate_list.usage;
> >>>        }
> >>>
> >>>        ret = ttm_eu_reserve_buffers(&ctx.ticket, &ctx.list,
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> >>> index 60ca14afb879..2ae1c0d9d33a 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> >>> @@ -55,8 +55,7 @@ static int amdgpu_cs_user_fence_chunk(struct amdgpu_cs_parser *p,
> >>>        bo = amdgpu_bo_ref(gem_to_amdgpu_bo(gobj));
> >>>        p->uf_entry.priority = 0;
> >>>        p->uf_entry.tv.bo = &bo->tbo;
> >>> -     /* One for TTM and two for the CS job */
> >>> -     p->uf_entry.tv.num_shared = 3;
> >>> +     p->uf_entry.tv.usage = DMA_RESV_USAGE_READ;
> >>>
> >>>        drm_gem_object_put(gobj);
> >>>
> >>> @@ -519,9 +518,8 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
> >>>                        return r;
> >>>        }
> >>>
> >>> -     /* One for TTM and one for the CS job */
> >>>        amdgpu_bo_list_for_each_entry(e, p->bo_list)
> >>> -             e->tv.num_shared = 2;
> >>> +             e->tv.usage = DMA_RESV_USAGE_READ;
> >>>
> >>>        amdgpu_bo_list_get_list(p->bo_list, &p->validated);
> >>>
> >>> @@ -1261,7 +1259,7 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
> >>>
> >>>        /* Make sure all BOs are remembered as writers */
> >>>        amdgpu_bo_list_for_each_entry(e, p->bo_list)
> >>> -             e->tv.num_shared = 0;
> >>> +             e->tv.usage = DMA_RESV_USAGE_WRITE;
> >>>
> >>>        ttm_eu_fence_buffer_objects(&p->ticket, &p->validated, p->fence);
> >>>        mutex_unlock(&p->adev->notifier_lock);
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c
> >>> index c6d4d41c4393..71277257d94d 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c
> >>> @@ -74,7 +74,7 @@ int amdgpu_map_static_csa(struct amdgpu_device *adev, struct amdgpu_vm *vm,
> >>>        INIT_LIST_HEAD(&list);
> >>>        INIT_LIST_HEAD(&csa_tv.head);
> >>>        csa_tv.bo = &bo->tbo;
> >>> -     csa_tv.num_shared = 1;
> >>> +     csa_tv.usage = DMA_RESV_USAGE_READ;
> >>>
> >>>        list_add(&csa_tv.head, &list);
> >>>        amdgpu_vm_get_pd_bo(vm, &list, &pd);
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> >>> index 84a53758e18e..7483411229f4 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> >>> @@ -207,7 +207,7 @@ static void amdgpu_gem_object_close(struct drm_gem_object *obj,
> >>>        INIT_LIST_HEAD(&duplicates);
> >>>
> >>>        tv.bo = &bo->tbo;
> >>> -     tv.num_shared = 2;
> >>> +     tv.usage = DMA_RESV_USAGE_READ;
> >>>        list_add(&tv.head, &list);
> >>>
> >>>        amdgpu_vm_get_pd_bo(vm, &list, &vm_pd);
> >>> @@ -731,9 +731,9 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data,
> >>>                abo = gem_to_amdgpu_bo(gobj);
> >>>                tv.bo = &abo->tbo;
> >>>                if (abo->flags & AMDGPU_GEM_CREATE_VM_ALWAYS_VALID)
> >>> -                     tv.num_shared = 1;
> >>> +                     tv.usage = DMA_RESV_USAGE_READ;
> >>>                else
> >>> -                     tv.num_shared = 0;
> >>> +                     tv.usage = DMA_RESV_USAGE_WRITE;
> >>>                list_add(&tv.head, &list);
> >>>        } else {
> >>>                gobj = NULL;
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c
> >>> index 5224d9a39737..f670d8473993 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c
> >>> @@ -319,7 +319,7 @@ static int amdgpu_vkms_prepare_fb(struct drm_plane *plane,
> >>>        INIT_LIST_HEAD(&list);
> >>>
> >>>        tv.bo = &rbo->tbo;
> >>> -     tv.num_shared = 1;
> >>> +     tv.usage = DMA_RESV_USAGE_READ;
> >>>        list_add(&tv.head, &list);
> >>>
> >>>        r = ttm_eu_reserve_buffers(&ticket, &list, false, NULL);
> >>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> >>> index 15184153e2b9..515be19ab279 100644
> >>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> >>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> >>> @@ -633,8 +633,7 @@ void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
> >>>    {
> >>>        entry->priority = 0;
> >>>        entry->tv.bo = &vm->root.bo->tbo;
> >>> -     /* Two for VM updates, one for TTM and one for the CS job */
> >>> -     entry->tv.num_shared = 4;
> >>> +     entry->tv.usage = DMA_RESV_USAGE_READ;
> >>>        entry->user_pages = NULL;
> >>>        list_add(&entry->tv.head, validated);
> >>>    }
> >>> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> >>> index b3fc3e958227..af844b636778 100644
> >>> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> >>> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> >>> @@ -1395,7 +1395,7 @@ static int svm_range_reserve_bos(struct svm_validate_context *ctx)
> >>>                vm = drm_priv_to_vm(pdd->drm_priv);
> >>>
> >>>                ctx->tv[gpuidx].bo = &vm->root.bo->tbo;
> >>> -             ctx->tv[gpuidx].num_shared = 4;
> >>> +             ctx->tv[gpuidx].usage = DMA_RESV_USAGE_READ;
> >>>                list_add(&ctx->tv[gpuidx].head, &ctx->validate_list);
> >>>        }
> >>>
> >>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >>> index 73423b805b54..851b7844b084 100644
> >>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> >>> @@ -7601,7 +7601,7 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
> >>>        INIT_LIST_HEAD(&list);
> >>>
> >>>        tv.bo = &rbo->tbo;
> >>> -     tv.num_shared = 1;
> >>> +     tv.usage = DMA_RESV_USAGE_READ;
> >>>        list_add(&tv.head, &list);
> >>>
> >>>        r = ttm_eu_reserve_buffers(&ticket, &list, false, NULL);
> >>> diff --git a/drivers/gpu/drm/qxl/qxl_release.c b/drivers/gpu/drm/qxl/qxl_release.c
> >>> index 368d26da0d6a..689e35192070 100644
> >>> --- a/drivers/gpu/drm/qxl/qxl_release.c
> >>> +++ b/drivers/gpu/drm/qxl/qxl_release.c
> >>> @@ -183,7 +183,7 @@ int qxl_release_list_add(struct qxl_release *release, struct qxl_bo *bo)
> >>>
> >>>        qxl_bo_ref(bo);
> >>>        entry->tv.bo = &bo->tbo;
> >>> -     entry->tv.num_shared = 0;
> >>> +     entry->tv.usage = DMA_RESV_USAGE_WRITE;
> >>>        list_add_tail(&entry->tv.head, &release->bos);
> >>>        return 0;
> >>>    }
> >>> diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c
> >>> index 446f7bae54c4..30afe0c62dd9 100644
> >>> --- a/drivers/gpu/drm/radeon/radeon_cs.c
> >>> +++ b/drivers/gpu/drm/radeon/radeon_cs.c
> >>> @@ -183,7 +183,8 @@ static int radeon_cs_parser_relocs(struct radeon_cs_parser *p)
> >>>                }
> >>>
> >>>                p->relocs[i].tv.bo = &p->relocs[i].robj->tbo;
> >>> -             p->relocs[i].tv.num_shared = !r->write_domain;
> >>> +             p->relocs[i].tv.usage =
> >>> +                     r->write_domain ? DMA_RESV_USAGE_WRITE : DMA_RESV_USAGE_READ;
> >>>
> >>>                radeon_cs_buckets_add(&buckets, &p->relocs[i].tv.head,
> >>>                                      priority);
> >>> @@ -258,7 +259,7 @@ static int radeon_cs_sync_rings(struct radeon_cs_parser *p)
> >>>
> >>>                resv = reloc->robj->tbo.base.resv;
> >>>                r = radeon_sync_resv(p->rdev, &p->ib.sync, resv,
> >>> -                                  reloc->tv.num_shared);
> >>> +                                  reloc->tv.usage != DMA_RESV_USAGE_WRITE);
> >>>                if (r)
> >>>                        return r;
> >>>        }
> >>> diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
> >>> index 8c01a7f0e027..eae47c709f5d 100644
> >>> --- a/drivers/gpu/drm/radeon/radeon_gem.c
> >>> +++ b/drivers/gpu/drm/radeon/radeon_gem.c
> >>> @@ -635,7 +635,7 @@ static void radeon_gem_va_update_vm(struct radeon_device *rdev,
> >>>        INIT_LIST_HEAD(&list);
> >>>
> >>>        tv.bo = &bo_va->bo->tbo;
> >>> -     tv.num_shared = 1;
> >>> +     tv.usage = DMA_RESV_USAGE_READ;
> >>>        list_add(&tv.head, &list);
> >>>
> >>>        vm_bos = radeon_vm_get_bos(rdev, bo_va->vm, &list);
> >>> diff --git a/drivers/gpu/drm/radeon/radeon_vm.c b/drivers/gpu/drm/radeon/radeon_vm.c
> >>> index 987cabbf1318..702627b48dae 100644
> >>> --- a/drivers/gpu/drm/radeon/radeon_vm.c
> >>> +++ b/drivers/gpu/drm/radeon/radeon_vm.c
> >>> @@ -143,7 +143,7 @@ struct radeon_bo_list *radeon_vm_get_bos(struct radeon_device *rdev,
> >>>        list[0].preferred_domains = RADEON_GEM_DOMAIN_VRAM;
> >>>        list[0].allowed_domains = RADEON_GEM_DOMAIN_VRAM;
> >>>        list[0].tv.bo = &vm->page_directory->tbo;
> >>> -     list[0].tv.num_shared = 1;
> >>> +     list[0].tv.usage = DMA_RESV_USAGE_READ;
> >>>        list[0].tiling_flags = 0;
> >>>        list_add(&list[0].tv.head, head);
> >>>
> >>> @@ -155,7 +155,7 @@ struct radeon_bo_list *radeon_vm_get_bos(struct radeon_device *rdev,
> >>>                list[idx].preferred_domains = RADEON_GEM_DOMAIN_VRAM;
> >>>                list[idx].allowed_domains = RADEON_GEM_DOMAIN_VRAM;
> >>>                list[idx].tv.bo = &list[idx].robj->tbo;
> >>> -             list[idx].tv.num_shared = 1;
> >>> +             list[idx].tv.usage = DMA_RESV_USAGE_READ;
> >>>                list[idx].tiling_flags = 0;
> >>>                list_add(&list[idx++].tv.head, head);
> >>>        }
> >>> diff --git a/drivers/gpu/drm/ttm/ttm_execbuf_util.c b/drivers/gpu/drm/ttm/ttm_execbuf_util.c
> >>> index 0eb995d25df1..c39d8e5ac271 100644
> >>> --- a/drivers/gpu/drm/ttm/ttm_execbuf_util.c
> >>> +++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c
> >>> @@ -101,7 +101,7 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
> >>>                        continue;
> >>>                }
> >>>
> >>> -             num_fences = min(entry->num_shared, 1u);
> >>> +             num_fences = entry->usage <= DMA_RESV_USAGE_WRITE ? 0u : 1u;
> >>>                if (!ret) {
> >>>                        ret = dma_resv_reserve_fences(bo->base.resv,
> >>>                                                      num_fences);
> >>> @@ -154,8 +154,7 @@ void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx *ticket,
> >>>        list_for_each_entry(entry, list, head) {
> >>>                struct ttm_buffer_object *bo = entry->bo;
> >>>
> >>> -             dma_resv_add_fence(bo->base.resv, fence, entry->num_shared ?
> >>> -                                DMA_RESV_USAGE_READ : DMA_RESV_USAGE_WRITE);
> >>> +             dma_resv_add_fence(bo->base.resv, fence, entry->usage);
> >>>                ttm_bo_move_to_lru_tail_unlocked(bo);
> >>>                dma_resv_unlock(bo->base.resv);
> >>>        }
> >>> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
> >>> index c6d02c98a19a..58dfff7d6c76 100644
> >>> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
> >>> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
> >>> @@ -130,7 +130,7 @@ static void vmw_resource_release(struct kref *kref)
> >>>                        struct ttm_validate_buffer val_buf;
> >>>
> >>>                        val_buf.bo = bo;
> >>> -                     val_buf.num_shared = 0;
> >>> +                     val_buf.usage = DMA_RESV_USAGE_WRITE;
> >>>                        res->func->unbind(res, false, &val_buf);
> >>>                }
> >>>                res->backup_dirty = false;
> >>> @@ -552,7 +552,7 @@ vmw_resource_check_buffer(struct ww_acquire_ctx *ticket,
> >>>        INIT_LIST_HEAD(&val_list);
> >>>        ttm_bo_get(&res->backup->base);
> >>>        val_buf->bo = &res->backup->base;
> >>> -     val_buf->num_shared = 0;
> >>> +     val_buf->usage = DMA_RESV_USAGE_WRITE;
> >>>        list_add_tail(&val_buf->head, &val_list);
> >>>        ret = ttm_eu_reserve_buffers(ticket, &val_list, interruptible, NULL);
> >>>        if (unlikely(ret != 0))
> >>> @@ -657,7 +657,7 @@ static int vmw_resource_do_evict(struct ww_acquire_ctx *ticket,
> >>>        BUG_ON(!func->may_evict);
> >>>
> >>>        val_buf.bo = NULL;
> >>> -     val_buf.num_shared = 0;
> >>> +     val_buf.usage = DMA_RESV_USAGE_WRITE;
> >>>        ret = vmw_resource_check_buffer(ticket, res, interruptible, &val_buf);
> >>>        if (unlikely(ret != 0))
> >>>                return ret;
> >>> @@ -708,7 +708,7 @@ int vmw_resource_validate(struct vmw_resource *res, bool intr,
> >>>                return 0;
> >>>
> >>>        val_buf.bo = NULL;
> >>> -     val_buf.num_shared = 0;
> >>> +     val_buf.usage = DMA_RESV_USAGE_WRITE;
> >>>        if (res->backup)
> >>>                val_buf.bo = &res->backup->base;
> >>>        do {
> >>> @@ -777,7 +777,7 @@ void vmw_resource_unbind_list(struct vmw_buffer_object *vbo)
> >>>    {
> >>>        struct ttm_validate_buffer val_buf = {
> >>>                .bo = &vbo->base,
> >>> -             .num_shared = 0
> >>> +             .usage = DMA_RESV_USAGE_WRITE
> >>>        };
> >>>
> >>>        dma_resv_assert_held(vbo->base.base.resv);
> >>> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_validation.c b/drivers/gpu/drm/vmwgfx/vmwgfx_validation.c
> >>> index f46891012be3..0476ba498321 100644
> >>> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_validation.c
> >>> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_validation.c
> >>> @@ -288,7 +288,7 @@ int vmw_validation_add_bo(struct vmw_validation_context *ctx,
> >>>                val_buf->bo = ttm_bo_get_unless_zero(&vbo->base);
> >>>                if (!val_buf->bo)
> >>>                        return -ESRCH;
> >>> -             val_buf->num_shared = 0;
> >>> +             val_buf->usage = DMA_RESV_USAGE_WRITE;
> >>>                list_add_tail(&val_buf->head, &ctx->bo_list);
> >>>                bo_node->as_mob = as_mob;
> >>>                bo_node->cpu_blit = cpu_blit;
> >>> diff --git a/include/drm/ttm/ttm_execbuf_util.h b/include/drm/ttm/ttm_execbuf_util.h
> >>> index a99d7fdf2964..851961a06c27 100644
> >>> --- a/include/drm/ttm/ttm_execbuf_util.h
> >>> +++ b/include/drm/ttm/ttm_execbuf_util.h
> >>> @@ -31,6 +31,7 @@
> >>>    #ifndef _TTM_EXECBUF_UTIL_H_
> >>>    #define _TTM_EXECBUF_UTIL_H_
> >>>
> >>> +#include <linux/dma-resv.h>
> >>>    #include <linux/list.h>
> >>>
> >>>    #include "ttm_bo_api.h"
> >>> @@ -46,7 +47,7 @@
> >>>    struct ttm_validate_buffer {
> >>>        struct list_head head;
> >>>        struct ttm_buffer_object *bo;
> >>> -     unsigned int num_shared;
> >>> +     enum dma_resv_usage usage;
> >>>    };
> >>>
> >>>    /**
>