Re: [PATCH] accel/ivpu: Rework bind/unbind of imported buffers

[Karol Wachowski <karol.wachowski@linux.intel.com>]

Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>

On 9/25/2025 4:50 PM, Maciej Falkowski wrote:
> From: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
>
> Ensure that imported buffers are properly mapped and unmapped in
> the same way as regular buffers to properly handle buffers during
> device's bind and unbind operations to prevent resource leaks and
> inconsistent buffer states.
>
> Imported buffers are now dma_mapped before submission and
> dma_unmapped in ivpu_bo_unbind(), guaranteeing they are unmapped
> when the device is unbound.
>
> Add also imported buffers to vdev->bo_list for consistent unmapping
> on device unbind. The bo->ctx_id is set in open() so imported
> buffers have a valid context ID.
>
> Debug logs have been updated to match the new code structure.
> The function ivpu_bo_pin() has been renamed to ivpu_bo_bind()
> to better reflect its purpose, and unbind tests have been refactored
> for improved coverage and clarity.
>
> Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
> Signed-off-by: Maciej Falkowski <maciej.falkowski@linux.intel.com>
> ---
>  drivers/accel/ivpu/ivpu_gem.c | 90 ++++++++++++++++++++++-------------
>  drivers/accel/ivpu/ivpu_gem.h |  2 +-
>  drivers/accel/ivpu/ivpu_job.c |  2 +-
>  3 files changed, 60 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/accel/ivpu/ivpu_gem.c b/drivers/accel/ivpu/ivpu_gem.c
> index cceb07232e12..0cb48aff396c 100644
> --- a/drivers/accel/ivpu/ivpu_gem.c
> +++ b/drivers/accel/ivpu/ivpu_gem.c
> @@ -28,8 +28,8 @@ static const struct drm_gem_object_funcs ivpu_gem_funcs;
>  static inline void ivpu_dbg_bo(struct ivpu_device *vdev, struct ivpu_bo *bo, const char *action)
>  {
>  	ivpu_dbg(vdev, BO,
> -		 "%6s: bo %8p vpu_addr %9llx size %8zu ctx %d has_pages %d dma_mapped %d mmu_mapped %d wc %d imported %d\n",
> -		 action, bo, bo->vpu_addr, ivpu_bo_size(bo), bo->ctx_id,
> +		 "%6s: bo %8p size %9zu ctx %d vpu_addr %9llx pages %d sgt %d mmu_mapped %d wc %d imported %d\n",
> +		 action, bo, ivpu_bo_size(bo), bo->ctx_id, bo->vpu_addr,
>  		 (bool)bo->base.pages, (bool)bo->base.sgt, bo->mmu_mapped, bo->base.map_wc,
>  		 (bool)drm_gem_is_imported(&bo->base.base));
>  }
> @@ -44,22 +44,46 @@ static inline void ivpu_bo_unlock(struct ivpu_bo *bo)
>  	dma_resv_unlock(bo->base.base.resv);
>  }
>  
> +static struct sg_table *ivpu_bo_map_attachment(struct ivpu_device *vdev, struct ivpu_bo *bo)
> +{
> +	struct sg_table *sgt = bo->base.sgt;
> +
> +	drm_WARN_ON(&vdev->drm, !bo->base.base.import_attach);
> +
> +	ivpu_bo_lock(bo);
> +
> +	if (!sgt) {
> +		sgt = dma_buf_map_attachment(bo->base.base.import_attach, DMA_BIDIRECTIONAL);
> +		if (IS_ERR(sgt))
> +			ivpu_err(vdev, "Failed to map BO in IOMMU: %ld\n", PTR_ERR(sgt));
> +		else
> +			bo->base.sgt = sgt;
> +	}
> +
> +	ivpu_bo_unlock(bo);
> +
> +	return sgt;
> +}
> +
>  /*
> - * ivpu_bo_pin() - pin the backing physical pages and map them to VPU.
> + * ivpu_bo_bind() - pin the backing physical pages and map them to VPU.
>   *
>   * This function pins physical memory pages, then maps the physical pages
>   * to IOMMU address space and finally updates the VPU MMU page tables
>   * to allow the VPU to translate VPU address to IOMMU address.
>   */
> -int __must_check ivpu_bo_pin(struct ivpu_bo *bo)
> +int __must_check ivpu_bo_bind(struct ivpu_bo *bo)
>  {
>  	struct ivpu_device *vdev = ivpu_bo_to_vdev(bo);
>  	struct sg_table *sgt;
>  	int ret = 0;
>  
> -	ivpu_dbg_bo(vdev, bo, "pin");
> +	ivpu_dbg_bo(vdev, bo, "bind");
>  
> -	sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
> +	if (bo->base.base.import_attach)
> +		sgt = ivpu_bo_map_attachment(vdev, bo);
> +	else
> +		sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
>  	if (IS_ERR(sgt)) {
>  		ret = PTR_ERR(sgt);
>  		ivpu_err(vdev, "Failed to map BO in IOMMU: %d\n", ret);
> @@ -100,7 +124,9 @@ ivpu_bo_alloc_vpu_addr(struct ivpu_bo *bo, struct ivpu_mmu_context *ctx,
>  	ret = ivpu_mmu_context_insert_node(ctx, range, ivpu_bo_size(bo), &bo->mm_node);
>  	if (!ret) {
>  		bo->ctx = ctx;
> +		bo->ctx_id = ctx->id;
>  		bo->vpu_addr = bo->mm_node.start;
> +		ivpu_dbg_bo(vdev, bo, "vaddr");
>  	} else {
>  		ivpu_err(vdev, "Failed to add BO to context %u: %d\n", ctx->id, ret);
>  	}
> @@ -116,7 +142,7 @@ static void ivpu_bo_unbind_locked(struct ivpu_bo *bo)
>  {
>  	struct ivpu_device *vdev = ivpu_bo_to_vdev(bo);
>  
> -	lockdep_assert(dma_resv_held(bo->base.base.resv) || !kref_read(&bo->base.base.refcount));
> +	dma_resv_assert_held(bo->base.base.resv);
>  
>  	if (bo->mmu_mapped) {
>  		drm_WARN_ON(&vdev->drm, !bo->ctx);
> @@ -135,9 +161,14 @@ static void ivpu_bo_unbind_locked(struct ivpu_bo *bo)
>  		return;
>  
>  	if (bo->base.sgt) {
> -		dma_unmap_sgtable(vdev->drm.dev, bo->base.sgt, DMA_BIDIRECTIONAL, 0);
> -		sg_free_table(bo->base.sgt);
> -		kfree(bo->base.sgt);
> +		if (bo->base.base.import_attach) {
> +			dma_buf_unmap_attachment(bo->base.base.import_attach,
> +						 bo->base.sgt, DMA_BIDIRECTIONAL);
> +		} else {
> +			dma_unmap_sgtable(vdev->drm.dev, bo->base.sgt, DMA_BIDIRECTIONAL, 0);
> +			sg_free_table(bo->base.sgt);
> +			kfree(bo->base.sgt);
> +		}
>  		bo->base.sgt = NULL;
>  	}
>  }
> @@ -163,6 +194,7 @@ void ivpu_bo_unbind_all_bos_from_context(struct ivpu_device *vdev, struct ivpu_m
>  
>  struct drm_gem_object *ivpu_gem_create_object(struct drm_device *dev, size_t size)
>  {
> +	struct ivpu_device *vdev = to_ivpu_device(dev);
>  	struct ivpu_bo *bo;
>  
>  	if (size == 0 || !PAGE_ALIGNED(size))
> @@ -177,6 +209,11 @@ struct drm_gem_object *ivpu_gem_create_object(struct drm_device *dev, size_t siz
>  
>  	INIT_LIST_HEAD(&bo->bo_list_node);
>  
> +	mutex_lock(&vdev->bo_list_lock);
> +	list_add_tail(&bo->bo_list_node, &vdev->bo_list);
> +	mutex_unlock(&vdev->bo_list_lock);
> +
> +	ivpu_dbg(vdev, BO, " alloc: bo %8p size %9zu\n", bo, size);
>  	return &bo->base.base;
>  }
>  
> @@ -185,7 +222,6 @@ struct drm_gem_object *ivpu_gem_prime_import(struct drm_device *dev,
>  {
>  	struct device *attach_dev = dev->dev;
>  	struct dma_buf_attachment *attach;
> -	struct sg_table *sgt;
>  	struct drm_gem_object *obj;
>  	int ret;
>  
> @@ -195,16 +231,10 @@ struct drm_gem_object *ivpu_gem_prime_import(struct drm_device *dev,
>  
>  	get_dma_buf(dma_buf);
>  
> -	sgt = dma_buf_map_attachment_unlocked(attach, DMA_BIDIRECTIONAL);
> -	if (IS_ERR(sgt)) {
> -		ret = PTR_ERR(sgt);
> -		goto fail_detach;
> -	}
> -
> -	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
> +	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, NULL);
>  	if (IS_ERR(obj)) {
>  		ret = PTR_ERR(obj);
> -		goto fail_unmap;
> +		goto fail_detach;
>  	}
>  
>  	obj->import_attach = attach;
> @@ -212,8 +242,6 @@ struct drm_gem_object *ivpu_gem_prime_import(struct drm_device *dev,
>  
>  	return obj;
>  
> -fail_unmap:
> -	dma_buf_unmap_attachment_unlocked(attach, sgt, DMA_BIDIRECTIONAL);
>  fail_detach:
>  	dma_buf_detach(dma_buf, attach);
>  	dma_buf_put(dma_buf);
> @@ -221,7 +249,7 @@ struct drm_gem_object *ivpu_gem_prime_import(struct drm_device *dev,
>  	return ERR_PTR(ret);
>  }
>  
> -static struct ivpu_bo *ivpu_bo_alloc(struct ivpu_device *vdev, u64 size, u32 flags, u32 ctx_id)
> +static struct ivpu_bo *ivpu_bo_alloc(struct ivpu_device *vdev, u64 size, u32 flags)
>  {
>  	struct drm_gem_shmem_object *shmem;
>  	struct ivpu_bo *bo;
> @@ -239,16 +267,9 @@ static struct ivpu_bo *ivpu_bo_alloc(struct ivpu_device *vdev, u64 size, u32 fla
>  		return ERR_CAST(shmem);
>  
>  	bo = to_ivpu_bo(&shmem->base);
> -	bo->ctx_id = ctx_id;
>  	bo->base.map_wc = flags & DRM_IVPU_BO_WC;
>  	bo->flags = flags;
>  
> -	mutex_lock(&vdev->bo_list_lock);
> -	list_add_tail(&bo->bo_list_node, &vdev->bo_list);
> -	mutex_unlock(&vdev->bo_list_lock);
> -
> -	ivpu_dbg_bo(vdev, bo, "alloc");
> -
>  	return bo;
>  }
>  
> @@ -282,6 +303,8 @@ static void ivpu_gem_bo_free(struct drm_gem_object *obj)
>  
>  	ivpu_dbg_bo(vdev, bo, "free");
>  
> +	drm_WARN_ON(&vdev->drm, list_empty(&bo->bo_list_node));
> +
>  	mutex_lock(&vdev->bo_list_lock);
>  	list_del(&bo->bo_list_node);
>  	mutex_unlock(&vdev->bo_list_lock);
> @@ -291,7 +314,10 @@ static void ivpu_gem_bo_free(struct drm_gem_object *obj)
>  	drm_WARN_ON(&vdev->drm, ivpu_bo_size(bo) == 0);
>  	drm_WARN_ON(&vdev->drm, bo->base.vaddr);
>  
> +	ivpu_bo_lock(bo);
>  	ivpu_bo_unbind_locked(bo);
> +	ivpu_bo_unlock(bo);
> +
>  	drm_WARN_ON(&vdev->drm, bo->mmu_mapped);
>  	drm_WARN_ON(&vdev->drm, bo->ctx);
>  
> @@ -327,7 +353,7 @@ int ivpu_bo_create_ioctl(struct drm_device *dev, void *data, struct drm_file *fi
>  	if (size == 0)
>  		return -EINVAL;
>  
> -	bo = ivpu_bo_alloc(vdev, size, args->flags, file_priv->ctx.id);
> +	bo = ivpu_bo_alloc(vdev, size, args->flags);
>  	if (IS_ERR(bo)) {
>  		ivpu_err(vdev, "Failed to allocate BO: %pe (ctx %u size %llu flags 0x%x)",
>  			 bo, file_priv->ctx.id, args->size, args->flags);
> @@ -361,7 +387,7 @@ ivpu_bo_create(struct ivpu_device *vdev, struct ivpu_mmu_context *ctx,
>  	drm_WARN_ON(&vdev->drm, !PAGE_ALIGNED(range->end));
>  	drm_WARN_ON(&vdev->drm, !PAGE_ALIGNED(size));
>  
> -	bo = ivpu_bo_alloc(vdev, size, flags, IVPU_GLOBAL_CONTEXT_MMU_SSID);
> +	bo = ivpu_bo_alloc(vdev, size, flags);
>  	if (IS_ERR(bo)) {
>  		ivpu_err(vdev, "Failed to allocate BO: %pe (vpu_addr 0x%llx size %llu flags 0x%x)",
>  			 bo, range->start, size, flags);
> @@ -372,7 +398,7 @@ ivpu_bo_create(struct ivpu_device *vdev, struct ivpu_mmu_context *ctx,
>  	if (ret)
>  		goto err_put;
>  
> -	ret = ivpu_bo_pin(bo);
> +	ret = ivpu_bo_bind(bo);
>  	if (ret)
>  		goto err_put;
>  
> diff --git a/drivers/accel/ivpu/ivpu_gem.h b/drivers/accel/ivpu/ivpu_gem.h
> index 3a208f3bf0a6..54452eb8a41f 100644
> --- a/drivers/accel/ivpu/ivpu_gem.h
> +++ b/drivers/accel/ivpu/ivpu_gem.h
> @@ -24,7 +24,7 @@ struct ivpu_bo {
>  	bool mmu_mapped;
>  };
>  
> -int ivpu_bo_pin(struct ivpu_bo *bo);
> +int ivpu_bo_bind(struct ivpu_bo *bo);
>  void ivpu_bo_unbind_all_bos_from_context(struct ivpu_device *vdev, struct ivpu_mmu_context *ctx);
>  
>  struct drm_gem_object *ivpu_gem_create_object(struct drm_device *dev, size_t size);
> diff --git a/drivers/accel/ivpu/ivpu_job.c b/drivers/accel/ivpu/ivpu_job.c
> index 044268d0fc87..17273c68f84c 100644
> --- a/drivers/accel/ivpu/ivpu_job.c
> +++ b/drivers/accel/ivpu/ivpu_job.c
> @@ -751,7 +751,7 @@ ivpu_job_prepare_bos_for_submit(struct drm_file *file, struct ivpu_job *job, u32
>  
>  		job->bos[i] = to_ivpu_bo(obj);
>  
> -		ret = ivpu_bo_pin(job->bos[i]);
> +		ret = ivpu_bo_bind(job->bos[i]);
>  		if (ret)
>  			return ret;
>  	}