drivers/gpu/drm/i915/i915_gem_dmabuf.c - arm/linux - Git at Google

 /*
  * Copyright 2012 Red Hat Inc
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice (including the next
  * paragraph) shall be included in all copies or substantial portions of the
  * Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  * DEALINGS IN THE SOFTWARE.
  *
  * Authors:
  *	Dave Airlie <airlied@redhat.com>
  */

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

 #include <drm/drmP.h>

 #include "i915_drv.h"

 static struct drm_i915_gem_object *dma_buf_to_obj(struct dma_buf *buf)
 {
 	return to_intel_bo(buf->priv);
 }

 static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachment,
 					     enum dma_data_direction dir)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
 	struct sg_table *st;
 	struct scatterlist *src, *dst;
 	int ret, i;

 	ret = i915_gem_object_pin_pages(obj);
 	if (ret)
 		goto err;

 	/* Copy sg so that we make an independent mapping */
 	st = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
 	if (st == NULL) {
 		ret = -ENOMEM;
 		goto err_unpin_pages;
 	}

 	ret = sg_alloc_table(st, obj->mm.pages->nents, GFP_KERNEL);
 	if (ret)
 		goto err_free;

 	src = obj->mm.pages->sgl;
 	dst = st->sgl;
 	for (i = 0; i < obj->mm.pages->nents; i++) {
 		sg_set_page(dst, sg_page(src), src->length, 0);
 		dst = sg_next(dst);
 		src = sg_next(src);
 	}

 	if (!dma_map_sg(attachment->dev, st->sgl, st->nents, dir)) {
 		ret = -ENOMEM;
 		goto err_free_sg;
 	}

 	return st;

 err_free_sg:
 	sg_free_table(st);
 err_free:
 	kfree(st);
 err_unpin_pages:
 	i915_gem_object_unpin_pages(obj);
 err:
 	return ERR_PTR(ret);
 }

 static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
 				   struct sg_table *sg,
 				   enum dma_data_direction dir)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);

 	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
 	sg_free_table(sg);
 	kfree(sg);

 	i915_gem_object_unpin_pages(obj);
 }

 static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);

 	return i915_gem_object_pin_map(obj, I915_MAP_WB);
 }

 static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);

 	i915_gem_object_unpin_map(obj);
 }

 static void *i915_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
 {
 	return NULL;
 }

 static void i915_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 {

 }
 static void *i915_gem_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	struct page *page;

 	if (page_num >= obj->base.size >> PAGE_SHIFT)
 		return NULL;

 	if (!i915_gem_object_has_struct_page(obj))
 		return NULL;

 	if (i915_gem_object_pin_pages(obj))
 		return NULL;

 	/* Synchronisation is left to the caller (via .begin_cpu_access()) */
 	page = i915_gem_object_get_page(obj, page_num);
 	if (IS_ERR(page))
 		goto err_unpin;

 	return kmap(page);

 err_unpin:
 	i915_gem_object_unpin_pages(obj);
 	return NULL;
 }

 static void i915_gem_dmabuf_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);

 	kunmap(virt_to_page(addr));
 	i915_gem_object_unpin_pages(obj);
 }

 static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	int ret;

 	if (obj->base.size < vma->vm_end - vma->vm_start)
 		return -EINVAL;

 	if (!obj->base.filp)
 		return -ENODEV;

 	ret = call_mmap(obj->base.filp, vma);
 	if (ret)
 		return ret;

 	fput(vma->vm_file);
 	vma->vm_file = get_file(obj->base.filp);

 	return 0;
 }

 static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	struct drm_device *dev = obj->base.dev;
 	bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE);
 	int err;

 	err = i915_gem_object_pin_pages(obj);
 	if (err)
 		return err;

 	err = i915_mutex_lock_interruptible(dev);
 	if (err)
 		goto out;

 	err = i915_gem_object_set_to_cpu_domain(obj, write);
 	mutex_unlock(&dev->struct_mutex);

 out:
 	i915_gem_object_unpin_pages(obj);
 	return err;
 }

 static int i915_gem_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	struct drm_device *dev = obj->base.dev;
 	int err;

 	err = i915_gem_object_pin_pages(obj);
 	if (err)
 		return err;

 	err = i915_mutex_lock_interruptible(dev);
 	if (err)
 		goto out;

 	err = i915_gem_object_set_to_gtt_domain(obj, false);
 	mutex_unlock(&dev->struct_mutex);

 out:
 	i915_gem_object_unpin_pages(obj);
 	return err;
 }

 static const struct dma_buf_ops i915_dmabuf_ops =  {
 	.map_dma_buf = i915_gem_map_dma_buf,
 	.unmap_dma_buf = i915_gem_unmap_dma_buf,
 	.release = drm_gem_dmabuf_release,
 	.map = i915_gem_dmabuf_kmap,
 	.map_atomic = i915_gem_dmabuf_kmap_atomic,
 	.unmap = i915_gem_dmabuf_kunmap,
 	.unmap_atomic = i915_gem_dmabuf_kunmap_atomic,
 	.mmap = i915_gem_dmabuf_mmap,
 	.vmap = i915_gem_dmabuf_vmap,
 	.vunmap = i915_gem_dmabuf_vunmap,
 	.begin_cpu_access = i915_gem_begin_cpu_access,
 	.end_cpu_access = i915_gem_end_cpu_access,
 };

 struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
 				      struct drm_gem_object *gem_obj, int flags)
 {
 	struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

 	exp_info.ops = &i915_dmabuf_ops;
 	exp_info.size = gem_obj->size;
 	exp_info.flags = flags;
 	exp_info.priv = gem_obj;
 	exp_info.resv = obj->resv;

 	if (obj->ops->dmabuf_export) {
 		int ret = obj->ops->dmabuf_export(obj);
 		if (ret)
 			return ERR_PTR(ret);
 	}

 	return drm_gem_dmabuf_export(dev, &exp_info);
 }

 static struct sg_table *
 i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
 {
 	return dma_buf_map_attachment(obj->base.import_attach,
 				      DMA_BIDIRECTIONAL);
 }

 static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj,
 					     struct sg_table *pages)
 {
 	dma_buf_unmap_attachment(obj->base.import_attach, pages,
 				 DMA_BIDIRECTIONAL);
 }

 static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = {
 	.get_pages = i915_gem_object_get_pages_dmabuf,
 	.put_pages = i915_gem_object_put_pages_dmabuf,
 };

 struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
 					     struct dma_buf *dma_buf)
 {
 	struct dma_buf_attachment *attach;
 	struct drm_i915_gem_object *obj;
 	int ret;

 	/* is this one of own objects? */
 	if (dma_buf->ops == &i915_dmabuf_ops) {
 		obj = dma_buf_to_obj(dma_buf);
 		/* is it from our device? */
 		if (obj->base.dev == dev) {
 			/*
 			 * Importing dmabuf exported from out own gem increases
 			 * refcount on gem itself instead of f_count of dmabuf.
 			 */
 			return &i915_gem_object_get(obj)->base;
 		}
 	}

 	/* need to attach */
 	attach = dma_buf_attach(dma_buf, dev->dev);
 	if (IS_ERR(attach))
 		return ERR_CAST(attach);

 	get_dma_buf(dma_buf);

 	obj = i915_gem_object_alloc(to_i915(dev));
 	if (obj == NULL) {
 		ret = -ENOMEM;
 		goto fail_detach;
 	}

 	drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
 	i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
 	obj->base.import_attach = attach;
 	obj->resv = dma_buf->resv;

 	/* We use GTT as shorthand for a coherent domain, one that is
 	 * neither in the GPU cache nor in the CPU cache, where all
 	 * writes are immediately visible in memory. (That's not strictly
 	 * true, but it's close! There are internal buffers such as the
 	 * write-combined buffer or a delay through the chipset for GTT
 	 * writes that do require us to treat GTT as a separate cache domain.)
 	 */
 	obj->base.read_domains = I915_GEM_DOMAIN_GTT;
 	obj->base.write_domain = 0;

 	return &obj->base;

 fail_detach:
 	dma_buf_detach(dma_buf, attach);
 	dma_buf_put(dma_buf);

 	return ERR_PTR(ret);
 }

 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 #include "selftests/mock_dmabuf.c"
 #include "selftests/i915_gem_dmabuf.c"
 #endif
	/*
	* Copyright 2012 Red Hat Inc
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice (including the next
	* paragraph) shall be included in all copies or substantial portions of the
	* Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
	* DEALINGS IN THE SOFTWARE.
	*
	* Authors:
	* Dave Airlie <airlied@redhat.com>
	*/

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

	#include <drm/drmP.h>

	#include "i915_drv.h"

	static struct drm_i915_gem_object dma_buf_to_obj(struct dma_buf buf)
	{
	return to_intel_bo(buf->priv);
	}

	static struct sg_table i915_gem_map_dma_buf(struct dma_buf_attachment attachment,
	enum dma_data_direction dir)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
	struct sg_table *st;
	struct scatterlist src, dst;
	int ret, i;

	ret = i915_gem_object_pin_pages(obj);
	if (ret)
	goto err;

	/* Copy sg so that we make an independent mapping */
	st = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
	if (st == NULL) {
	ret = -ENOMEM;
	goto err_unpin_pages;
	}

	ret = sg_alloc_table(st, obj->mm.pages->nents, GFP_KERNEL);
	if (ret)
	goto err_free;

	src = obj->mm.pages->sgl;
	dst = st->sgl;
	for (i = 0; i < obj->mm.pages->nents; i++) {
	sg_set_page(dst, sg_page(src), src->length, 0);
	dst = sg_next(dst);
	src = sg_next(src);
	}

	if (!dma_map_sg(attachment->dev, st->sgl, st->nents, dir)) {
	ret = -ENOMEM;
	goto err_free_sg;
	}

	return st;

	err_free_sg:
	sg_free_table(st);
	err_free:
	kfree(st);
	err_unpin_pages:
	i915_gem_object_unpin_pages(obj);
	err:
	return ERR_PTR(ret);
	}

	static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
	struct sg_table *sg,
	enum dma_data_direction dir)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);

	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
	sg_free_table(sg);
	kfree(sg);

	i915_gem_object_unpin_pages(obj);
	}

	static void i915_gem_dmabuf_vmap(struct dma_buf dma_buf)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);

	return i915_gem_object_pin_map(obj, I915_MAP_WB);
	}

	static void i915_gem_dmabuf_vunmap(struct dma_buf dma_buf, void vaddr)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);

	i915_gem_object_unpin_map(obj);
	}

	static void i915_gem_dmabuf_kmap_atomic(struct dma_buf dma_buf, unsigned long page_num)
	{
	return NULL;
	}

	static void i915_gem_dmabuf_kunmap_atomic(struct dma_buf dma_buf, unsigned long page_num, void addr)
	{

	}
	static void i915_gem_dmabuf_kmap(struct dma_buf dma_buf, unsigned long page_num)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
	struct page *page;

	if (page_num >= obj->base.size >> PAGE_SHIFT)
	return NULL;

	if (!i915_gem_object_has_struct_page(obj))
	return NULL;

	if (i915_gem_object_pin_pages(obj))
	return NULL;

	/* Synchronisation is left to the caller (via .begin_cpu_access()) */
	page = i915_gem_object_get_page(obj, page_num);
	if (IS_ERR(page))
	goto err_unpin;

	return kmap(page);

	err_unpin:
	i915_gem_object_unpin_pages(obj);
	return NULL;
	}

	static void i915_gem_dmabuf_kunmap(struct dma_buf dma_buf, unsigned long page_num, void addr)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);

	kunmap(virt_to_page(addr));
	i915_gem_object_unpin_pages(obj);
	}

	static int i915_gem_dmabuf_mmap(struct dma_buf dma_buf, struct vm_area_struct vma)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
	int ret;

	if (obj->base.size < vma->vm_end - vma->vm_start)
	return -EINVAL;

	if (!obj->base.filp)
	return -ENODEV;

	ret = call_mmap(obj->base.filp, vma);
	if (ret)
	return ret;

	fput(vma->vm_file);
	vma->vm_file = get_file(obj->base.filp);

	return 0;
	}

	static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
	struct drm_device *dev = obj->base.dev;
	bool write = (direction == DMA_BIDIRECTIONAL \|\| direction == DMA_TO_DEVICE);
	int err;

	err = i915_gem_object_pin_pages(obj);
	if (err)
	return err;

	err = i915_mutex_lock_interruptible(dev);
	if (err)
	goto out;

	err = i915_gem_object_set_to_cpu_domain(obj, write);
	mutex_unlock(&dev->struct_mutex);

	out:
	i915_gem_object_unpin_pages(obj);
	return err;
	}

	static int i915_gem_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
	{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
	struct drm_device *dev = obj->base.dev;
	int err;

	err = i915_gem_object_pin_pages(obj);
	if (err)
	return err;

	err = i915_mutex_lock_interruptible(dev);
	if (err)
	goto out;

	err = i915_gem_object_set_to_gtt_domain(obj, false);
	mutex_unlock(&dev->struct_mutex);

	out:
	i915_gem_object_unpin_pages(obj);
	return err;
	}

	static const struct dma_buf_ops i915_dmabuf_ops = {
	.map_dma_buf = i915_gem_map_dma_buf,
	.unmap_dma_buf = i915_gem_unmap_dma_buf,
	.release = drm_gem_dmabuf_release,
	.map = i915_gem_dmabuf_kmap,
	.map_atomic = i915_gem_dmabuf_kmap_atomic,
	.unmap = i915_gem_dmabuf_kunmap,
	.unmap_atomic = i915_gem_dmabuf_kunmap_atomic,
	.mmap = i915_gem_dmabuf_mmap,
	.vmap = i915_gem_dmabuf_vmap,
	.vunmap = i915_gem_dmabuf_vunmap,
	.begin_cpu_access = i915_gem_begin_cpu_access,
	.end_cpu_access = i915_gem_end_cpu_access,
	};

	struct dma_buf i915_gem_prime_export(struct drm_device dev,
	struct drm_gem_object *gem_obj, int flags)
	{
	struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

	exp_info.ops = &i915_dmabuf_ops;
	exp_info.size = gem_obj->size;
	exp_info.flags = flags;
	exp_info.priv = gem_obj;
	exp_info.resv = obj->resv;

	if (obj->ops->dmabuf_export) {
	int ret = obj->ops->dmabuf_export(obj);
	if (ret)
	return ERR_PTR(ret);
	}

	return drm_gem_dmabuf_export(dev, &exp_info);
	}

	static struct sg_table *
	i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
	{
	return dma_buf_map_attachment(obj->base.import_attach,
	DMA_BIDIRECTIONAL);
	}

	static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj,
	struct sg_table *pages)
	{
	dma_buf_unmap_attachment(obj->base.import_attach, pages,
	DMA_BIDIRECTIONAL);
	}

	static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = {
	.get_pages = i915_gem_object_get_pages_dmabuf,
	.put_pages = i915_gem_object_put_pages_dmabuf,
	};

	struct drm_gem_object i915_gem_prime_import(struct drm_device dev,
	struct dma_buf *dma_buf)
	{
	struct dma_buf_attachment *attach;
	struct drm_i915_gem_object *obj;
	int ret;

	/* is this one of own objects? */
	if (dma_buf->ops == &i915_dmabuf_ops) {
	obj = dma_buf_to_obj(dma_buf);
	/* is it from our device? */
	if (obj->base.dev == dev) {
	/*
	* Importing dmabuf exported from out own gem increases
	* refcount on gem itself instead of f_count of dmabuf.
	*/
	return &i915_gem_object_get(obj)->base;
	}
	}

	/* need to attach */
	attach = dma_buf_attach(dma_buf, dev->dev);
	if (IS_ERR(attach))
	return ERR_CAST(attach);

	get_dma_buf(dma_buf);

	obj = i915_gem_object_alloc(to_i915(dev));
	if (obj == NULL) {
	ret = -ENOMEM;
	goto fail_detach;
	}

	drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
	i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
	obj->base.import_attach = attach;
	obj->resv = dma_buf->resv;

	/* We use GTT as shorthand for a coherent domain, one that is
	* neither in the GPU cache nor in the CPU cache, where all
	* writes are immediately visible in memory. (That's not strictly
	* true, but it's close! There are internal buffers such as the
	* write-combined buffer or a delay through the chipset for GTT
	* writes that do require us to treat GTT as a separate cache domain.)
	*/
	obj->base.read_domains = I915_GEM_DOMAIN_GTT;
	obj->base.write_domain = 0;

	return &obj->base;

	fail_detach:
	dma_buf_detach(dma_buf, attach);
	dma_buf_put(dma_buf);

	return ERR_PTR(ret);
	}

	#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
	#include "selftests/mock_dmabuf.c"
	#include "selftests/i915_gem_dmabuf.c"
	#endif