drivers/gpu/drm/v3d/v3d_bo.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /* Copyright (C) 2015-2018 Broadcom */

 /**
  * DOC: V3D GEM BO management support
  *
  * Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the
  * GPU and the bus, allowing us to use shmem objects for our storage
  * instead of CMA.
  *
  * Physically contiguous objects may still be imported to V3D, but the
  * driver doesn't allocate physically contiguous objects on its own.
  * Display engines requiring physically contiguous allocations should
  * look into Mesa's "renderonly" support (as used by the Mesa pl111
  * driver) for an example of how to integrate with V3D.
  *
  * Long term, we should support evicting pages from the MMU when under
  * memory pressure (thus the v3d_bo_get_pages() refcounting), but
  * that's not a high priority since our systems tend to not have swap.
  */

 #include <linux/dma-buf.h>
 #include <linux/pfn_t.h>

 #include "v3d_drv.h"
 #include "uapi/drm/v3d_drm.h"

 /* Pins the shmem pages, fills in the .pages and .sgt fields of the BO, and maps
  * it for DMA.
  */
 static int
 v3d_bo_get_pages(struct v3d_bo *bo)
 {
 	struct drm_gem_object *obj = &bo->base;
 	struct drm_device *dev = obj->dev;
 	int npages = obj->size >> PAGE_SHIFT;
 	int ret = 0;

 	mutex_lock(&bo->lock);
 	if (bo->pages_refcount++ != 0)
 		goto unlock;

 	if (!obj->import_attach) {
 		bo->pages = drm_gem_get_pages(obj);
 		if (IS_ERR(bo->pages)) {
 			ret = PTR_ERR(bo->pages);
 			goto unlock;
 		}

 		bo->sgt = drm_prime_pages_to_sg(bo->pages, npages);
 		if (IS_ERR(bo->sgt)) {
 			ret = PTR_ERR(bo->sgt);
 			goto put_pages;
 		}

 		/* Map the pages for use by the GPU. */
 		dma_map_sg(dev->dev, bo->sgt->sgl,
 			   bo->sgt->nents, DMA_BIDIRECTIONAL);
 	} else {
 		bo->pages = kcalloc(npages, sizeof(*bo->pages), GFP_KERNEL);
 		if (!bo->pages)
 			goto put_pages;

 		drm_prime_sg_to_page_addr_arrays(bo->sgt, bo->pages,
 						 NULL, npages);

 		/* Note that dma-bufs come in mapped. */
 	}

 	mutex_unlock(&bo->lock);

 	return 0;

 put_pages:
 	drm_gem_put_pages(obj, bo->pages, true, true);
 	bo->pages = NULL;
 unlock:
 	bo->pages_refcount--;
 	mutex_unlock(&bo->lock);
 	return ret;
 }

 static void
 v3d_bo_put_pages(struct v3d_bo *bo)
 {
 	struct drm_gem_object *obj = &bo->base;

 	mutex_lock(&bo->lock);
 	if (--bo->pages_refcount == 0) {
 		if (!obj->import_attach) {
 			dma_unmap_sg(obj->dev->dev, bo->sgt->sgl,
 				     bo->sgt->nents, DMA_BIDIRECTIONAL);
 			sg_free_table(bo->sgt);
 			kfree(bo->sgt);
 			drm_gem_put_pages(obj, bo->pages, true, true);
 		} else {
 			kfree(bo->pages);
 		}
 	}
 	mutex_unlock(&bo->lock);
 }

 static struct v3d_bo *v3d_bo_create_struct(struct drm_device *dev,
 					   size_t unaligned_size)
 {
 	struct v3d_dev *v3d = to_v3d_dev(dev);
 	struct drm_gem_object *obj;
 	struct v3d_bo *bo;
 	size_t size = roundup(unaligned_size, PAGE_SIZE);
 	int ret;

 	if (size == 0)
 		return ERR_PTR(-EINVAL);

 	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
 	if (!bo)
 		return ERR_PTR(-ENOMEM);
 	obj = &bo->base;

 	INIT_LIST_HEAD(&bo->vmas);
 	INIT_LIST_HEAD(&bo->unref_head);
 	mutex_init(&bo->lock);

 	ret = drm_gem_object_init(dev, obj, size);
 	if (ret)
 		goto free_bo;

 	spin_lock(&v3d->mm_lock);
 	ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
 					 obj->size >> PAGE_SHIFT,
 					 GMP_GRANULARITY >> PAGE_SHIFT, 0, 0);
 	spin_unlock(&v3d->mm_lock);
 	if (ret)
 		goto free_obj;

 	return bo;

 free_obj:
 	drm_gem_object_release(obj);
 free_bo:
 	kfree(bo);
 	return ERR_PTR(ret);
 }

 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
 			     size_t unaligned_size)
 {
 	struct v3d_dev *v3d = to_v3d_dev(dev);
 	struct drm_gem_object *obj;
 	struct v3d_bo *bo;
 	int ret;

 	bo = v3d_bo_create_struct(dev, unaligned_size);
 	if (IS_ERR(bo))
 		return bo;
 	obj = &bo->base;

 	bo->resv = &bo->_resv;
 	reservation_object_init(bo->resv);

 	ret = v3d_bo_get_pages(bo);
 	if (ret)
 		goto free_mm;

 	v3d_mmu_insert_ptes(bo);

 	mutex_lock(&v3d->bo_lock);
 	v3d->bo_stats.num_allocated++;
 	v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT;
 	mutex_unlock(&v3d->bo_lock);

 	return bo;

 free_mm:
 	spin_lock(&v3d->mm_lock);
 	drm_mm_remove_node(&bo->node);
 	spin_unlock(&v3d->mm_lock);

 	drm_gem_object_release(obj);
 	kfree(bo);
 	return ERR_PTR(ret);
 }

 /* Called DRM core on the last userspace/kernel unreference of the
  * BO.
  */
 void v3d_free_object(struct drm_gem_object *obj)
 {
 	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
 	struct v3d_bo *bo = to_v3d_bo(obj);

 	mutex_lock(&v3d->bo_lock);
 	v3d->bo_stats.num_allocated--;
 	v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT;
 	mutex_unlock(&v3d->bo_lock);

 	reservation_object_fini(&bo->_resv);

 	v3d_bo_put_pages(bo);

 	if (obj->import_attach)
 		drm_prime_gem_destroy(obj, bo->sgt);

 	v3d_mmu_remove_ptes(bo);
 	spin_lock(&v3d->mm_lock);
 	drm_mm_remove_node(&bo->node);
 	spin_unlock(&v3d->mm_lock);

 	mutex_destroy(&bo->lock);

 	drm_gem_object_release(obj);
 	kfree(bo);
 }

 struct reservation_object *v3d_prime_res_obj(struct drm_gem_object *obj)
 {
 	struct v3d_bo *bo = to_v3d_bo(obj);

 	return bo->resv;
 }

 static void
 v3d_set_mmap_vma_flags(struct vm_area_struct *vma)
 {
 	vma->vm_flags &= ~VM_PFNMAP;
 	vma->vm_flags |= VM_MIXEDMAP;
 	vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 }

 vm_fault_t v3d_gem_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
 	struct drm_gem_object *obj = vma->vm_private_data;
 	struct v3d_bo *bo = to_v3d_bo(obj);
 	pfn_t pfn;
 	pgoff_t pgoff;

 	/* We don't use vmf->pgoff since that has the fake offset: */
 	pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
 	pfn = __pfn_to_pfn_t(page_to_pfn(bo->pages[pgoff]), PFN_DEV);

 	return vmf_insert_mixed(vma, vmf->address, pfn);
 }

 int v3d_mmap(struct file *filp, struct vm_area_struct *vma)
 {
 	int ret;

 	ret = drm_gem_mmap(filp, vma);
 	if (ret)
 		return ret;

 	v3d_set_mmap_vma_flags(vma);

 	return ret;
 }

 int v3d_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
 {
 	int ret;

 	ret = drm_gem_mmap_obj(obj, obj->size, vma);
 	if (ret < 0)
 		return ret;

 	v3d_set_mmap_vma_flags(vma);

 	return 0;
 }

 struct sg_table *
 v3d_prime_get_sg_table(struct drm_gem_object *obj)
 {
 	struct v3d_bo *bo = to_v3d_bo(obj);
 	int npages = obj->size >> PAGE_SHIFT;

 	return drm_prime_pages_to_sg(bo->pages, npages);
 }

 struct drm_gem_object *
 v3d_prime_import_sg_table(struct drm_device *dev,
 			  struct dma_buf_attachment *attach,
 			  struct sg_table *sgt)
 {
 	struct drm_gem_object *obj;
 	struct v3d_bo *bo;

 	bo = v3d_bo_create_struct(dev, attach->dmabuf->size);
 	if (IS_ERR(bo))
 		return ERR_CAST(bo);
 	obj = &bo->base;

 	bo->resv = attach->dmabuf->resv;

 	bo->sgt = sgt;
 	v3d_bo_get_pages(bo);

 	v3d_mmu_insert_ptes(bo);

 	return obj;
 }

 int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file_priv)
 {
 	struct drm_v3d_create_bo *args = data;
 	struct v3d_bo *bo = NULL;
 	int ret;

 	if (args->flags != 0) {
 		DRM_INFO("unknown create_bo flags: %d\n", args->flags);
 		return -EINVAL;
 	}

 	bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
 	if (IS_ERR(bo))
 		return PTR_ERR(bo);

 	args->offset = bo->node.start << PAGE_SHIFT;

 	ret = drm_gem_handle_create(file_priv, &bo->base, &args->handle);
 	drm_gem_object_put_unlocked(&bo->base);

 	return ret;
 }

 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
 		      struct drm_file *file_priv)
 {
 	struct drm_v3d_mmap_bo *args = data;
 	struct drm_gem_object *gem_obj;
 	int ret;

 	if (args->flags != 0) {
 		DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
 		return -EINVAL;
 	}

 	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
 	if (!gem_obj) {
 		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
 		return -ENOENT;
 	}

 	ret = drm_gem_create_mmap_offset(gem_obj);
 	if (ret == 0)
 		args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
 	drm_gem_object_put_unlocked(gem_obj);

 	return ret;
 }

 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
 			    struct drm_file *file_priv)
 {
 	struct drm_v3d_get_bo_offset *args = data;
 	struct drm_gem_object *gem_obj;
 	struct v3d_bo *bo;

 	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
 	if (!gem_obj) {
 		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
 		return -ENOENT;
 	}
 	bo = to_v3d_bo(gem_obj);

 	args->offset = bo->node.start << PAGE_SHIFT;

 	drm_gem_object_put_unlocked(gem_obj);
 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0+
	/* Copyright (C) 2015-2018 Broadcom */

	/**
	* DOC: V3D GEM BO management support
	*
	* Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the
	* GPU and the bus, allowing us to use shmem objects for our storage
	* instead of CMA.
	*
	* Physically contiguous objects may still be imported to V3D, but the
	* driver doesn't allocate physically contiguous objects on its own.
	* Display engines requiring physically contiguous allocations should
	* look into Mesa's "renderonly" support (as used by the Mesa pl111
	* driver) for an example of how to integrate with V3D.
	*
	* Long term, we should support evicting pages from the MMU when under
	* memory pressure (thus the v3d_bo_get_pages() refcounting), but
	* that's not a high priority since our systems tend to not have swap.
	*/

	#include <linux/dma-buf.h>
	#include <linux/pfn_t.h>

	#include "v3d_drv.h"
	#include "uapi/drm/v3d_drm.h"

	/* Pins the shmem pages, fills in the .pages and .sgt fields of the BO, and maps
	* it for DMA.
	*/
	static int
	v3d_bo_get_pages(struct v3d_bo *bo)
	{
	struct drm_gem_object *obj = &bo->base;
	struct drm_device *dev = obj->dev;
	int npages = obj->size >> PAGE_SHIFT;
	int ret = 0;

	mutex_lock(&bo->lock);
	if (bo->pages_refcount++ != 0)
	goto unlock;

	if (!obj->import_attach) {
	bo->pages = drm_gem_get_pages(obj);
	if (IS_ERR(bo->pages)) {
	ret = PTR_ERR(bo->pages);
	goto unlock;
	}

	bo->sgt = drm_prime_pages_to_sg(bo->pages, npages);
	if (IS_ERR(bo->sgt)) {
	ret = PTR_ERR(bo->sgt);
	goto put_pages;
	}

	/* Map the pages for use by the GPU. */
	dma_map_sg(dev->dev, bo->sgt->sgl,
	bo->sgt->nents, DMA_BIDIRECTIONAL);
	} else {
	bo->pages = kcalloc(npages, sizeof(*bo->pages), GFP_KERNEL);
	if (!bo->pages)
	goto put_pages;

	drm_prime_sg_to_page_addr_arrays(bo->sgt, bo->pages,
	NULL, npages);

	/* Note that dma-bufs come in mapped. */
	}

	mutex_unlock(&bo->lock);

	return 0;

	put_pages:
	drm_gem_put_pages(obj, bo->pages, true, true);
	bo->pages = NULL;
	unlock:
	bo->pages_refcount--;
	mutex_unlock(&bo->lock);
	return ret;
	}

	static void
	v3d_bo_put_pages(struct v3d_bo *bo)
	{
	struct drm_gem_object *obj = &bo->base;

	mutex_lock(&bo->lock);
	if (--bo->pages_refcount == 0) {
	if (!obj->import_attach) {
	dma_unmap_sg(obj->dev->dev, bo->sgt->sgl,
	bo->sgt->nents, DMA_BIDIRECTIONAL);
	sg_free_table(bo->sgt);
	kfree(bo->sgt);
	drm_gem_put_pages(obj, bo->pages, true, true);
	} else {
	kfree(bo->pages);
	}
	}
	mutex_unlock(&bo->lock);
	}

	static struct v3d_bo v3d_bo_create_struct(struct drm_device dev,
	size_t unaligned_size)
	{
	struct v3d_dev *v3d = to_v3d_dev(dev);
	struct drm_gem_object *obj;
	struct v3d_bo *bo;
	size_t size = roundup(unaligned_size, PAGE_SIZE);
	int ret;

	if (size == 0)
	return ERR_PTR(-EINVAL);

	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
	if (!bo)
	return ERR_PTR(-ENOMEM);
	obj = &bo->base;

	INIT_LIST_HEAD(&bo->vmas);
	INIT_LIST_HEAD(&bo->unref_head);
	mutex_init(&bo->lock);

	ret = drm_gem_object_init(dev, obj, size);
	if (ret)
	goto free_bo;

	spin_lock(&v3d->mm_lock);
	ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
	obj->size >> PAGE_SHIFT,
	GMP_GRANULARITY >> PAGE_SHIFT, 0, 0);
	spin_unlock(&v3d->mm_lock);
	if (ret)
	goto free_obj;

	return bo;

	free_obj:
	drm_gem_object_release(obj);
	free_bo:
	kfree(bo);
	return ERR_PTR(ret);
	}

	struct v3d_bo v3d_bo_create(struct drm_device dev, struct drm_file *file_priv,
	size_t unaligned_size)
	{
	struct v3d_dev *v3d = to_v3d_dev(dev);
	struct drm_gem_object *obj;
	struct v3d_bo *bo;
	int ret;

	bo = v3d_bo_create_struct(dev, unaligned_size);
	if (IS_ERR(bo))
	return bo;
	obj = &bo->base;

	bo->resv = &bo->_resv;
	reservation_object_init(bo->resv);

	ret = v3d_bo_get_pages(bo);
	if (ret)
	goto free_mm;

	v3d_mmu_insert_ptes(bo);

	mutex_lock(&v3d->bo_lock);
	v3d->bo_stats.num_allocated++;
	v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT;
	mutex_unlock(&v3d->bo_lock);

	return bo;

	free_mm:
	spin_lock(&v3d->mm_lock);
	drm_mm_remove_node(&bo->node);
	spin_unlock(&v3d->mm_lock);

	drm_gem_object_release(obj);
	kfree(bo);
	return ERR_PTR(ret);
	}

	/* Called DRM core on the last userspace/kernel unreference of the
	* BO.
	*/
	void v3d_free_object(struct drm_gem_object *obj)
	{
	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
	struct v3d_bo *bo = to_v3d_bo(obj);

	mutex_lock(&v3d->bo_lock);
	v3d->bo_stats.num_allocated--;
	v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT;
	mutex_unlock(&v3d->bo_lock);

	reservation_object_fini(&bo->_resv);

	v3d_bo_put_pages(bo);

	if (obj->import_attach)
	drm_prime_gem_destroy(obj, bo->sgt);

	v3d_mmu_remove_ptes(bo);
	spin_lock(&v3d->mm_lock);
	drm_mm_remove_node(&bo->node);
	spin_unlock(&v3d->mm_lock);

	mutex_destroy(&bo->lock);

	drm_gem_object_release(obj);
	kfree(bo);
	}

	struct reservation_object v3d_prime_res_obj(struct drm_gem_object obj)
	{
	struct v3d_bo *bo = to_v3d_bo(obj);

	return bo->resv;
	}

	static void
	v3d_set_mmap_vma_flags(struct vm_area_struct *vma)
	{
	vma->vm_flags &= ~VM_PFNMAP;
	vma->vm_flags \|= VM_MIXEDMAP;
	vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
	}

	vm_fault_t v3d_gem_fault(struct vm_fault *vmf)
	{
	struct vm_area_struct *vma = vmf->vma;
	struct drm_gem_object *obj = vma->vm_private_data;
	struct v3d_bo *bo = to_v3d_bo(obj);
	pfn_t pfn;
	pgoff_t pgoff;

	/* We don't use vmf->pgoff since that has the fake offset: */
	pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
	pfn = __pfn_to_pfn_t(page_to_pfn(bo->pages[pgoff]), PFN_DEV);

	return vmf_insert_mixed(vma, vmf->address, pfn);
	}

	int v3d_mmap(struct file filp, struct vm_area_struct vma)
	{
	int ret;

	ret = drm_gem_mmap(filp, vma);
	if (ret)
	return ret;

	v3d_set_mmap_vma_flags(vma);

	return ret;
	}

	int v3d_prime_mmap(struct drm_gem_object obj, struct vm_area_struct vma)
	{
	int ret;

	ret = drm_gem_mmap_obj(obj, obj->size, vma);
	if (ret < 0)
	return ret;

	v3d_set_mmap_vma_flags(vma);

	return 0;
	}

	struct sg_table *
	v3d_prime_get_sg_table(struct drm_gem_object *obj)
	{
	struct v3d_bo *bo = to_v3d_bo(obj);
	int npages = obj->size >> PAGE_SHIFT;

	return drm_prime_pages_to_sg(bo->pages, npages);
	}

	struct drm_gem_object *
	v3d_prime_import_sg_table(struct drm_device *dev,
	struct dma_buf_attachment *attach,
	struct sg_table *sgt)
	{
	struct drm_gem_object *obj;
	struct v3d_bo *bo;

	bo = v3d_bo_create_struct(dev, attach->dmabuf->size);
	if (IS_ERR(bo))
	return ERR_CAST(bo);
	obj = &bo->base;

	bo->resv = attach->dmabuf->resv;

	bo->sgt = sgt;
	v3d_bo_get_pages(bo);

	v3d_mmu_insert_ptes(bo);

	return obj;
	}

	int v3d_create_bo_ioctl(struct drm_device dev, void data,
	struct drm_file *file_priv)
	{
	struct drm_v3d_create_bo *args = data;
	struct v3d_bo *bo = NULL;
	int ret;

	if (args->flags != 0) {
	DRM_INFO("unknown create_bo flags: %d\n", args->flags);
	return -EINVAL;
	}

	bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
	if (IS_ERR(bo))
	return PTR_ERR(bo);

	args->offset = bo->node.start << PAGE_SHIFT;

	ret = drm_gem_handle_create(file_priv, &bo->base, &args->handle);
	drm_gem_object_put_unlocked(&bo->base);

	return ret;
	}

	int v3d_mmap_bo_ioctl(struct drm_device dev, void data,
	struct drm_file *file_priv)
	{
	struct drm_v3d_mmap_bo *args = data;
	struct drm_gem_object *gem_obj;
	int ret;

	if (args->flags != 0) {
	DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
	return -EINVAL;
	}

	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
	if (!gem_obj) {
	DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
	return -ENOENT;
	}

	ret = drm_gem_create_mmap_offset(gem_obj);
	if (ret == 0)
	args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
	drm_gem_object_put_unlocked(gem_obj);

	return ret;
	}

	int v3d_get_bo_offset_ioctl(struct drm_device dev, void data,
	struct drm_file *file_priv)
	{
	struct drm_v3d_get_bo_offset *args = data;
	struct drm_gem_object *gem_obj;
	struct v3d_bo *bo;

	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
	if (!gem_obj) {
	DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
	return -ENOENT;
	}
	bo = to_v3d_bo(gem_obj);

	args->offset = bo->node.start << PAGE_SHIFT;

	drm_gem_object_put_unlocked(gem_obj);
	return 0;
	}