drivers/gpu/drm/vgem/vgem_drv.c - kernel/bruno - Git at Google

 /*
  * Copyright 2011 Red Hat, Inc.
  * Copyright © 2014 The Chromium OS Authors
  *
  * 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
  * on the rights to use, copy, modify, merge, publish, distribute, sub
  * license, and/or sell copies of the Software, and to permit persons to whom
  * them 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 MERCHANTIBILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
  * THE AUTHORS 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:
  *	Adam Jackson <ajax@redhat.com>
  *	Ben Widawsky <ben@bwidawsk.net>
  */

 /**
  * This is vgem, a (non-hardware-backed) GEM service.  This is used by Mesa's
  * software renderer and the X server for efficient buffer sharing.
  */

 #include <linux/module.h>
 #include <linux/ramfs.h>
 #include <linux/shmem_fs.h>
 #include <linux/dma-buf.h>
 #include "vgem_drv.h"

 #define DRIVER_NAME	"vgem"
 #define DRIVER_DESC	"Virtual GEM provider"
 #define DRIVER_DATE	"20120112"
 #define DRIVER_MAJOR	1
 #define DRIVER_MINOR	0

 void vgem_gem_put_pages(struct drm_vgem_gem_object *obj)
 {
 	drm_gem_put_pages(&obj->base, obj->pages, false, false);
 	obj->pages = NULL;
 }

 static void vgem_gem_free_object(struct drm_gem_object *obj)
 {
 	struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);

 	drm_gem_free_mmap_offset(obj);

 	if (vgem_obj->use_dma_buf && obj->dma_buf) {
 		dma_buf_put(obj->dma_buf);
 		obj->dma_buf = NULL;
 	}

 	drm_gem_object_release(obj);

 	if (vgem_obj->pages)
 		vgem_gem_put_pages(vgem_obj);

 	vgem_obj->pages = NULL;

 	kfree(vgem_obj);
 }

 int vgem_gem_get_pages(struct drm_vgem_gem_object *obj)
 {
 	struct page **pages;

 	if (obj->pages || obj->use_dma_buf)
 		return 0;

 	pages = drm_gem_get_pages(&obj->base);
 	if (IS_ERR(pages)) {
 		return PTR_ERR(pages);
 	}

 	obj->pages = pages;

 	return 0;
 }

 static int vgem_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct drm_vgem_gem_object *obj = vma->vm_private_data;
 	struct drm_device *dev = obj->base.dev;
 	loff_t num_pages;
 	pgoff_t page_offset;
 	int ret;

 	/* We don't use vmf->pgoff since that has the fake offset */
 	page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
 		PAGE_SHIFT;

 	num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE);

 	if (page_offset > num_pages)
 		return VM_FAULT_SIGBUS;

 	mutex_lock(&dev->struct_mutex);

 	ret = vm_insert_page(vma, (unsigned long)vmf->virtual_address,
 			     obj->pages[page_offset]);

 	mutex_unlock(&dev->struct_mutex);
 	switch (ret) {
 	case 0:
 		return VM_FAULT_NOPAGE;
 	case -ENOMEM:
 		return VM_FAULT_OOM;
 	case -EBUSY:
 		return VM_FAULT_RETRY;
 	case -EFAULT:
 	case -EINVAL:
 		return VM_FAULT_SIGBUS;
 	default:
 		WARN_ON(1);
 		return VM_FAULT_SIGBUS;
 	}
 }

 static const struct vm_operations_struct vgem_gem_vm_ops = {
 	.fault = vgem_gem_fault,
 	.open = drm_gem_vm_open,
 	.close = drm_gem_vm_close,
 };

 /* ioctls */

 static struct drm_gem_object *vgem_gem_create(struct drm_device *dev,
 					      struct drm_file *file,
 					      unsigned int *handle,
 					      unsigned long size)
 {
 	struct drm_vgem_gem_object *obj;
 	struct drm_gem_object *gem_object;
 	int err;

 	size = roundup(size, PAGE_SIZE);

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

 	gem_object = &obj->base;

 	err = drm_gem_object_init(dev, gem_object, size);
 	if (err)
 		goto out;

 	err = drm_gem_handle_create(file, gem_object, handle);
 	if (err)
 		goto handle_out;

 	drm_gem_object_unreference_unlocked(gem_object);

 	return gem_object;

 handle_out:
 	drm_gem_object_release(gem_object);
 out:
 	kfree(obj);
 	return ERR_PTR(err);
 }

 static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 				struct drm_mode_create_dumb *args)
 {
 	struct drm_gem_object *gem_object;
 	uint64_t size;
 	uint64_t pitch = args->width * DIV_ROUND_UP(args->bpp, 8);

 	size = args->height * pitch;
 	if (size == 0)
 		return -EINVAL;

 	gem_object = vgem_gem_create(dev, file, &args->handle, size);

 	if (IS_ERR(gem_object)) {
 		DRM_DEBUG_DRIVER("object creation failed\n");
 		return PTR_ERR(gem_object);
 	}

 	args->size = gem_object->size;
 	args->pitch = pitch;

 	DRM_DEBUG_DRIVER("Created object of size %lld\n", size);

 	return 0;
 }

 int vgem_gem_dumb_map(struct drm_file *file, struct drm_device *dev,
 		      uint32_t handle, uint64_t *offset)
 {
 	int ret = 0;
 	struct drm_gem_object *obj;

 	mutex_lock(&dev->struct_mutex);
 	obj = drm_gem_object_lookup(dev, file, handle);
 	if (!obj) {
 		ret = -ENOENT;
 		goto unlock;
 	}

 	if (!drm_vma_node_has_offset(&obj->vma_node)) {
 		ret = drm_gem_create_mmap_offset(obj);
 		if (ret)
 			goto unref;
 	}

 	BUG_ON(!obj->filp);

 	obj->filp->private_data = obj;

 	ret = vgem_gem_get_pages(to_vgem_bo(obj));
 	if (ret)
 		goto fail_get_pages;

 	*offset = drm_vma_node_offset_addr(&obj->vma_node);

 	goto unref;

 fail_get_pages:
 	drm_gem_free_mmap_offset(obj);
 unref:
 	drm_gem_object_unreference(obj);
 unlock:
 	mutex_unlock(&dev->struct_mutex);
 	return ret;
 }

 static struct drm_ioctl_desc vgem_ioctls[] = {
 };

 static const struct file_operations vgem_driver_fops = {
 	.owner		= THIS_MODULE,
 	.open		= drm_open,
 	.mmap		= drm_gem_mmap,
 	.poll		= drm_poll,
 	.read		= drm_read,
 	.unlocked_ioctl = drm_ioctl,
 	.release	= drm_release,
 };

 static struct drm_driver vgem_driver = {
 	.driver_features		= DRIVER_GEM,
 	.gem_free_object		= vgem_gem_free_object,
 	.gem_vm_ops			= &vgem_gem_vm_ops,
 	.ioctls				= vgem_ioctls,
 	.fops				= &vgem_driver_fops,
 	.dumb_create			= vgem_gem_dumb_create,
 	.dumb_map_offset		= vgem_gem_dumb_map,
 	.name	= DRIVER_NAME,
 	.desc	= DRIVER_DESC,
 	.date	= DRIVER_DATE,
 	.major	= DRIVER_MAJOR,
 	.minor	= DRIVER_MINOR,
 };

 struct drm_device *vgem_device;

 static int __init vgem_init(void)
 {
 	int ret;

 	vgem_device = drm_dev_alloc(&vgem_driver, NULL);
 	if (!vgem_device) {
 		ret = -ENOMEM;
 		goto out;
 	}

 	drm_dev_set_unique(vgem_device, "vgem");

 	ret  = drm_dev_register(vgem_device, 0);

 	if (ret)
 		goto out_unref;

 	return 0;

 out_unref:
 	drm_dev_unref(vgem_device);
 out:
 	return ret;
 }

 static void __exit vgem_exit(void)
 {
 	drm_dev_unregister(vgem_device);
 	drm_dev_unref(vgem_device);
 }

 module_init(vgem_init);
 module_exit(vgem_exit);

 MODULE_AUTHOR("Red Hat, Inc.");
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL and additional rights");
	/*
	* Copyright 2011 Red Hat, Inc.
	* Copyright © 2014 The Chromium OS Authors
	*
	* 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
	* on the rights to use, copy, modify, merge, publish, distribute, sub
	* license, and/or sell copies of the Software, and to permit persons to whom
	* them 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 MERCHANTIBILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS 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:
	* Adam Jackson <ajax@redhat.com>
	* Ben Widawsky <ben@bwidawsk.net>
	*/

	/**
	* This is vgem, a (non-hardware-backed) GEM service. This is used by Mesa's
	* software renderer and the X server for efficient buffer sharing.
	*/

	#include <linux/module.h>
	#include <linux/ramfs.h>
	#include <linux/shmem_fs.h>
	#include <linux/dma-buf.h>
	#include "vgem_drv.h"

	#define DRIVER_NAME "vgem"
	#define DRIVER_DESC "Virtual GEM provider"
	#define DRIVER_DATE "20120112"
	#define DRIVER_MAJOR 1
	#define DRIVER_MINOR 0

	void vgem_gem_put_pages(struct drm_vgem_gem_object *obj)
	{
	drm_gem_put_pages(&obj->base, obj->pages, false, false);
	obj->pages = NULL;
	}

	static void vgem_gem_free_object(struct drm_gem_object *obj)
	{
	struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);

	drm_gem_free_mmap_offset(obj);

	if (vgem_obj->use_dma_buf && obj->dma_buf) {
	dma_buf_put(obj->dma_buf);
	obj->dma_buf = NULL;
	}

	drm_gem_object_release(obj);

	if (vgem_obj->pages)
	vgem_gem_put_pages(vgem_obj);

	vgem_obj->pages = NULL;

	kfree(vgem_obj);
	}

	int vgem_gem_get_pages(struct drm_vgem_gem_object *obj)
	{
	struct page **pages;

	if (obj->pages \|\| obj->use_dma_buf)
	return 0;

	pages = drm_gem_get_pages(&obj->base);
	if (IS_ERR(pages)) {
	return PTR_ERR(pages);
	}

	obj->pages = pages;

	return 0;
	}

	static int vgem_gem_fault(struct vm_area_struct vma, struct vm_fault vmf)
	{
	struct drm_vgem_gem_object *obj = vma->vm_private_data;
	struct drm_device *dev = obj->base.dev;
	loff_t num_pages;
	pgoff_t page_offset;
	int ret;

	/* We don't use vmf->pgoff since that has the fake offset */
	page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
	PAGE_SHIFT;

	num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE);

	if (page_offset > num_pages)
	return VM_FAULT_SIGBUS;

	mutex_lock(&dev->struct_mutex);

	ret = vm_insert_page(vma, (unsigned long)vmf->virtual_address,
	obj->pages[page_offset]);

	mutex_unlock(&dev->struct_mutex);
	switch (ret) {
	case 0:
	return VM_FAULT_NOPAGE;
	case -ENOMEM:
	return VM_FAULT_OOM;
	case -EBUSY:
	return VM_FAULT_RETRY;
	case -EFAULT:
	case -EINVAL:
	return VM_FAULT_SIGBUS;
	default:
	WARN_ON(1);
	return VM_FAULT_SIGBUS;
	}
	}

	static const struct vm_operations_struct vgem_gem_vm_ops = {
	.fault = vgem_gem_fault,
	.open = drm_gem_vm_open,
	.close = drm_gem_vm_close,
	};

	/* ioctls */

	static struct drm_gem_object vgem_gem_create(struct drm_device dev,
	struct drm_file *file,
	unsigned int *handle,
	unsigned long size)
	{
	struct drm_vgem_gem_object *obj;
	struct drm_gem_object *gem_object;
	int err;

	size = roundup(size, PAGE_SIZE);

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

	gem_object = &obj->base;

	err = drm_gem_object_init(dev, gem_object, size);
	if (err)
	goto out;

	err = drm_gem_handle_create(file, gem_object, handle);
	if (err)
	goto handle_out;

	drm_gem_object_unreference_unlocked(gem_object);

	return gem_object;

	handle_out:
	drm_gem_object_release(gem_object);
	out:
	kfree(obj);
	return ERR_PTR(err);
	}

	static int vgem_gem_dumb_create(struct drm_file file, struct drm_device dev,
	struct drm_mode_create_dumb *args)
	{
	struct drm_gem_object *gem_object;
	uint64_t size;
	uint64_t pitch = args->width * DIV_ROUND_UP(args->bpp, 8);

	size = args->height * pitch;
	if (size == 0)
	return -EINVAL;

	gem_object = vgem_gem_create(dev, file, &args->handle, size);

	if (IS_ERR(gem_object)) {
	DRM_DEBUG_DRIVER("object creation failed\n");
	return PTR_ERR(gem_object);
	}

	args->size = gem_object->size;
	args->pitch = pitch;

	DRM_DEBUG_DRIVER("Created object of size %lld\n", size);

	return 0;
	}

	int vgem_gem_dumb_map(struct drm_file file, struct drm_device dev,
	uint32_t handle, uint64_t *offset)
	{
	int ret = 0;
	struct drm_gem_object *obj;

	mutex_lock(&dev->struct_mutex);
	obj = drm_gem_object_lookup(dev, file, handle);
	if (!obj) {
	ret = -ENOENT;
	goto unlock;
	}

	if (!drm_vma_node_has_offset(&obj->vma_node)) {
	ret = drm_gem_create_mmap_offset(obj);
	if (ret)
	goto unref;
	}

	BUG_ON(!obj->filp);

	obj->filp->private_data = obj;

	ret = vgem_gem_get_pages(to_vgem_bo(obj));
	if (ret)
	goto fail_get_pages;

	*offset = drm_vma_node_offset_addr(&obj->vma_node);

	goto unref;

	fail_get_pages:
	drm_gem_free_mmap_offset(obj);
	unref:
	drm_gem_object_unreference(obj);
	unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
	}

	static struct drm_ioctl_desc vgem_ioctls[] = {
	};

	static const struct file_operations vgem_driver_fops = {
	.owner = THIS_MODULE,
	.open = drm_open,
	.mmap = drm_gem_mmap,
	.poll = drm_poll,
	.read = drm_read,
	.unlocked_ioctl = drm_ioctl,
	.release = drm_release,
	};

	static struct drm_driver vgem_driver = {
	.driver_features = DRIVER_GEM,
	.gem_free_object = vgem_gem_free_object,
	.gem_vm_ops = &vgem_gem_vm_ops,
	.ioctls = vgem_ioctls,
	.fops = &vgem_driver_fops,
	.dumb_create = vgem_gem_dumb_create,
	.dumb_map_offset = vgem_gem_dumb_map,
	.name = DRIVER_NAME,
	.desc = DRIVER_DESC,
	.date = DRIVER_DATE,
	.major = DRIVER_MAJOR,
	.minor = DRIVER_MINOR,
	};

	struct drm_device *vgem_device;

	static int __init vgem_init(void)
	{
	int ret;

	vgem_device = drm_dev_alloc(&vgem_driver, NULL);
	if (!vgem_device) {
	ret = -ENOMEM;
	goto out;
	}

	drm_dev_set_unique(vgem_device, "vgem");

	ret = drm_dev_register(vgem_device, 0);

	if (ret)
	goto out_unref;

	return 0;

	out_unref:
	drm_dev_unref(vgem_device);
	out:
	return ret;
	}

	static void __exit vgem_exit(void)
	{
	drm_dev_unregister(vgem_device);
	drm_dev_unref(vgem_device);
	}

	module_init(vgem_init);
	module_exit(vgem_exit);

	MODULE_AUTHOR("Red Hat, Inc.");
	MODULE_DESCRIPTION(DRIVER_DESC);
	MODULE_LICENSE("GPL and additional rights");