drivers/gpu/drm/drm_gem_cma_helper.c - kernel/msm-4.19 - Gitiles

 /*
  * drm gem CMA (contiguous memory allocator) helper functions
  *
  * Copyright (C) 2012 Sascha Hauer, Pengutronix
  *
  * Based on Samsung Exynos code
  *
  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version 2
  * of the License, or (at your option) any later version.
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  */

 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/export.h>
 #include <linux/dma-mapping.h>

 #include <drm/drmP.h>
 #include <drm/drm.h>
 #include <drm/drm_gem_cma_helper.h>

 static unsigned int get_gem_mmap_offset(struct drm_gem_object *obj)
 {
 	return (unsigned int)obj->map_list.hash.key << PAGE_SHIFT;
 }

 static void drm_gem_cma_buf_destroy(struct drm_device *drm,
 		struct drm_gem_cma_object *cma_obj)
 {
 	dma_free_writecombine(drm->dev, cma_obj->base.size, cma_obj->vaddr,
 			cma_obj->paddr);
 }

 /*
  * drm_gem_cma_create - allocate an object with the given size
  *
  * returns a struct drm_gem_cma_object* on success or ERR_PTR values
  * on failure.
  */
 struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,
 		unsigned int size)
 {
 	struct drm_gem_cma_object *cma_obj;
 	struct drm_gem_object *gem_obj;
 	int ret;

 	size = round_up(size, PAGE_SIZE);

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

 	cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
 			&cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
 	if (!cma_obj->vaddr) {
 		dev_err(drm->dev, "failed to allocate buffer with size %d\n", size);
 		ret = -ENOMEM;
 		goto err_dma_alloc;
 	}

 	gem_obj = &cma_obj->base;

 	ret = drm_gem_object_init(drm, gem_obj, size);
 	if (ret)
 		goto err_obj_init;

 	ret = drm_gem_create_mmap_offset(gem_obj);
 	if (ret)
 		goto err_create_mmap_offset;

 	return cma_obj;

 err_create_mmap_offset:
 	drm_gem_object_release(gem_obj);

 err_obj_init:
 	drm_gem_cma_buf_destroy(drm, cma_obj);

 err_dma_alloc:
 	kfree(cma_obj);

 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_create);

 /*
  * drm_gem_cma_create_with_handle - allocate an object with the given
  * size and create a gem handle on it
  *
  * returns a struct drm_gem_cma_object* on success or ERR_PTR values
  * on failure.
  */
 static struct drm_gem_cma_object *drm_gem_cma_create_with_handle(
 		struct drm_file *file_priv,
 		struct drm_device *drm, unsigned int size,
 		unsigned int *handle)
 {
 	struct drm_gem_cma_object *cma_obj;
 	struct drm_gem_object *gem_obj;
 	int ret;

 	cma_obj = drm_gem_cma_create(drm, size);
 	if (IS_ERR(cma_obj))
 		return cma_obj;

 	gem_obj = &cma_obj->base;

 	/*
 	 * allocate a id of idr table where the obj is registered
 	 * and handle has the id what user can see.
 	 */
 	ret = drm_gem_handle_create(file_priv, gem_obj, handle);
 	if (ret)
 		goto err_handle_create;

 	/* drop reference from allocate - handle holds it now. */
 	drm_gem_object_unreference_unlocked(gem_obj);

 	return cma_obj;

 err_handle_create:
 	drm_gem_cma_free_object(gem_obj);

 	return ERR_PTR(ret);
 }

 /*
  * drm_gem_cma_free_object - (struct drm_driver)->gem_free_object callback
  * function
  */
 void drm_gem_cma_free_object(struct drm_gem_object *gem_obj)
 {
 	struct drm_gem_cma_object *cma_obj;

 	if (gem_obj->map_list.map)
 		drm_gem_free_mmap_offset(gem_obj);

 	drm_gem_object_release(gem_obj);

 	cma_obj = to_drm_gem_cma_obj(gem_obj);

 	drm_gem_cma_buf_destroy(gem_obj->dev, cma_obj);

 	kfree(cma_obj);
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_free_object);

 /*
  * drm_gem_cma_dumb_create - (struct drm_driver)->dumb_create callback
  * function
  *
  * This aligns the pitch and size arguments to the minimum required. wrap
  * this into your own function if you need bigger alignment.
  */
 int drm_gem_cma_dumb_create(struct drm_file *file_priv,
 		struct drm_device *dev, struct drm_mode_create_dumb *args)
 {
 	struct drm_gem_cma_object *cma_obj;
 	int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);

 	if (args->pitch < min_pitch)
 		args->pitch = min_pitch;

 	if (args->size < args->pitch * args->height)
 		args->size = args->pitch * args->height;

 	cma_obj = drm_gem_cma_create_with_handle(file_priv, dev,
 			args->size, &args->handle);
 	if (IS_ERR(cma_obj))
 		return PTR_ERR(cma_obj);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create);

 /*
  * drm_gem_cma_dumb_map_offset - (struct drm_driver)->dumb_map_offset callback
  * function
  */
 int drm_gem_cma_dumb_map_offset(struct drm_file *file_priv,
 		struct drm_device *drm, uint32_t handle, uint64_t *offset)
 {
 	struct drm_gem_object *gem_obj;

 	mutex_lock(&drm->struct_mutex);

 	gem_obj = drm_gem_object_lookup(drm, file_priv, handle);
 	if (!gem_obj) {
 		dev_err(drm->dev, "failed to lookup gem object\n");
 		mutex_unlock(&drm->struct_mutex);
 		return -EINVAL;
 	}

 	*offset = get_gem_mmap_offset(gem_obj);

 	drm_gem_object_unreference(gem_obj);

 	mutex_unlock(&drm->struct_mutex);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_map_offset);

 const struct vm_operations_struct drm_gem_cma_vm_ops = {
 	.open = drm_gem_vm_open,
 	.close = drm_gem_vm_close,
 };
 EXPORT_SYMBOL_GPL(drm_gem_cma_vm_ops);

 /*
  * drm_gem_cma_mmap - (struct file_operation)->mmap callback function
  */
 int drm_gem_cma_mmap(struct file *filp, struct vm_area_struct *vma)
 {
 	struct drm_gem_object *gem_obj;
 	struct drm_gem_cma_object *cma_obj;
 	int ret;

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

 	gem_obj = vma->vm_private_data;
 	cma_obj = to_drm_gem_cma_obj(gem_obj);

 	ret = remap_pfn_range(vma, vma->vm_start, cma_obj->paddr >> PAGE_SHIFT,
 			vma->vm_end - vma->vm_start, vma->vm_page_prot);
 	if (ret)
 		drm_gem_vm_close(vma);

 	return ret;
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_mmap);

 /*
  * drm_gem_cma_dumb_destroy - (struct drm_driver)->dumb_destroy callback function
  */
 int drm_gem_cma_dumb_destroy(struct drm_file *file_priv,
 		struct drm_device *drm, unsigned int handle)
 {
 	return drm_gem_handle_delete(file_priv, handle);
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_destroy);

 #ifdef CONFIG_DEBUG_FS
 void drm_gem_cma_describe(struct drm_gem_cma_object *cma_obj, struct seq_file *m)
 {
 	struct drm_gem_object *obj = &cma_obj->base;
 	struct drm_device *dev = obj->dev;
 	uint64_t off = 0;

 	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

 	if (obj->map_list.map)
 		off = (uint64_t)obj->map_list.hash.key;

 	seq_printf(m, "%2d (%2d) %08llx %08Zx %p %d",
 			obj->name, obj->refcount.refcount.counter,
 			off, cma_obj->paddr, cma_obj->vaddr, obj->size);

 	seq_printf(m, "\n");
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_describe);
 #endif
	/*
	* drm gem CMA (contiguous memory allocator) helper functions
	*
	* Copyright (C) 2012 Sascha Hauer, Pengutronix
	*
	* Based on Samsung Exynos code
	*
	* Copyright (c) 2011 Samsung Electronics Co., Ltd.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version 2
	* of the License, or (at your option) any later version.
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/

	#include <linux/mm.h>
	#include <linux/slab.h>
	#include <linux/mutex.h>
	#include <linux/export.h>
	#include <linux/dma-mapping.h>

	#include <drm/drmP.h>
	#include <drm/drm.h>
	#include <drm/drm_gem_cma_helper.h>

	static unsigned int get_gem_mmap_offset(struct drm_gem_object *obj)
	{
	return (unsigned int)obj->map_list.hash.key << PAGE_SHIFT;
	}

	static void drm_gem_cma_buf_destroy(struct drm_device *drm,
	struct drm_gem_cma_object *cma_obj)
	{
	dma_free_writecombine(drm->dev, cma_obj->base.size, cma_obj->vaddr,
	cma_obj->paddr);
	}

	/*
	* drm_gem_cma_create - allocate an object with the given size
	*
	* returns a struct drm_gem_cma_object* on success or ERR_PTR values
	* on failure.
	*/
	struct drm_gem_cma_object drm_gem_cma_create(struct drm_device drm,
	unsigned int size)
	{
	struct drm_gem_cma_object *cma_obj;
	struct drm_gem_object *gem_obj;
	int ret;

	size = round_up(size, PAGE_SIZE);

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

	cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
	&cma_obj->paddr, GFP_KERNEL \| __GFP_NOWARN);
	if (!cma_obj->vaddr) {
	dev_err(drm->dev, "failed to allocate buffer with size %d\n", size);
	ret = -ENOMEM;
	goto err_dma_alloc;
	}

	gem_obj = &cma_obj->base;

	ret = drm_gem_object_init(drm, gem_obj, size);
	if (ret)
	goto err_obj_init;

	ret = drm_gem_create_mmap_offset(gem_obj);
	if (ret)
	goto err_create_mmap_offset;

	return cma_obj;

	err_create_mmap_offset:
	drm_gem_object_release(gem_obj);

	err_obj_init:
	drm_gem_cma_buf_destroy(drm, cma_obj);

	err_dma_alloc:
	kfree(cma_obj);

	return ERR_PTR(ret);
	}
	EXPORT_SYMBOL_GPL(drm_gem_cma_create);

	/*
	* drm_gem_cma_create_with_handle - allocate an object with the given
	* size and create a gem handle on it
	*
	* returns a struct drm_gem_cma_object* on success or ERR_PTR values
	* on failure.
	*/
	static struct drm_gem_cma_object *drm_gem_cma_create_with_handle(
	struct drm_file *file_priv,
	struct drm_device *drm, unsigned int size,
	unsigned int *handle)
	{
	struct drm_gem_cma_object *cma_obj;
	struct drm_gem_object *gem_obj;
	int ret;

	cma_obj = drm_gem_cma_create(drm, size);
	if (IS_ERR(cma_obj))
	return cma_obj;

	gem_obj = &cma_obj->base;

	/*
	* allocate a id of idr table where the obj is registered
	* and handle has the id what user can see.
	*/
	ret = drm_gem_handle_create(file_priv, gem_obj, handle);
	if (ret)
	goto err_handle_create;

	/* drop reference from allocate - handle holds it now. */
	drm_gem_object_unreference_unlocked(gem_obj);

	return cma_obj;

	err_handle_create:
	drm_gem_cma_free_object(gem_obj);

	return ERR_PTR(ret);
	}

	/*
	* drm_gem_cma_free_object - (struct drm_driver)->gem_free_object callback
	* function
	*/
	void drm_gem_cma_free_object(struct drm_gem_object *gem_obj)
	{
	struct drm_gem_cma_object *cma_obj;

	if (gem_obj->map_list.map)
	drm_gem_free_mmap_offset(gem_obj);

	drm_gem_object_release(gem_obj);

	cma_obj = to_drm_gem_cma_obj(gem_obj);

	drm_gem_cma_buf_destroy(gem_obj->dev, cma_obj);

	kfree(cma_obj);
	}
	EXPORT_SYMBOL_GPL(drm_gem_cma_free_object);

	/*
	* drm_gem_cma_dumb_create - (struct drm_driver)->dumb_create callback
	* function
	*
	* This aligns the pitch and size arguments to the minimum required. wrap
	* this into your own function if you need bigger alignment.
	*/
	int drm_gem_cma_dumb_create(struct drm_file *file_priv,
	struct drm_device dev, struct drm_mode_create_dumb args)
	{
	struct drm_gem_cma_object *cma_obj;
	int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);

	if (args->pitch < min_pitch)
	args->pitch = min_pitch;

	if (args->size < args->pitch * args->height)
	args->size = args->pitch * args->height;

	cma_obj = drm_gem_cma_create_with_handle(file_priv, dev,
	args->size, &args->handle);
	if (IS_ERR(cma_obj))
	return PTR_ERR(cma_obj);

	return 0;
	}
	EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create);

	/*
	* drm_gem_cma_dumb_map_offset - (struct drm_driver)->dumb_map_offset callback
	* function
	*/
	int drm_gem_cma_dumb_map_offset(struct drm_file *file_priv,
	struct drm_device drm, uint32_t handle, uint64_t offset)
	{
	struct drm_gem_object *gem_obj;

	mutex_lock(&drm->struct_mutex);

	gem_obj = drm_gem_object_lookup(drm, file_priv, handle);
	if (!gem_obj) {
	dev_err(drm->dev, "failed to lookup gem object\n");
	mutex_unlock(&drm->struct_mutex);
	return -EINVAL;
	}

	*offset = get_gem_mmap_offset(gem_obj);

	drm_gem_object_unreference(gem_obj);

	mutex_unlock(&drm->struct_mutex);

	return 0;
	}
	EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_map_offset);

	const struct vm_operations_struct drm_gem_cma_vm_ops = {
	.open = drm_gem_vm_open,
	.close = drm_gem_vm_close,
	};
	EXPORT_SYMBOL_GPL(drm_gem_cma_vm_ops);

	/*
	* drm_gem_cma_mmap - (struct file_operation)->mmap callback function
	*/
	int drm_gem_cma_mmap(struct file filp, struct vm_area_struct vma)
	{
	struct drm_gem_object *gem_obj;
	struct drm_gem_cma_object *cma_obj;
	int ret;

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

	gem_obj = vma->vm_private_data;
	cma_obj = to_drm_gem_cma_obj(gem_obj);

	ret = remap_pfn_range(vma, vma->vm_start, cma_obj->paddr >> PAGE_SHIFT,
	vma->vm_end - vma->vm_start, vma->vm_page_prot);
	if (ret)
	drm_gem_vm_close(vma);

	return ret;
	}
	EXPORT_SYMBOL_GPL(drm_gem_cma_mmap);

	/*
	* drm_gem_cma_dumb_destroy - (struct drm_driver)->dumb_destroy callback function
	*/
	int drm_gem_cma_dumb_destroy(struct drm_file *file_priv,
	struct drm_device *drm, unsigned int handle)
	{
	return drm_gem_handle_delete(file_priv, handle);
	}
	EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_destroy);

	#ifdef CONFIG_DEBUG_FS
	void drm_gem_cma_describe(struct drm_gem_cma_object cma_obj, struct seq_file m)
	{
	struct drm_gem_object *obj = &cma_obj->base;
	struct drm_device *dev = obj->dev;
	uint64_t off = 0;

	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

	if (obj->map_list.map)
	off = (uint64_t)obj->map_list.hash.key;

	seq_printf(m, "%2d (%2d) %08llx %08Zx %p %d",
	obj->name, obj->refcount.refcount.counter,
	off, cma_obj->paddr, cma_obj->vaddr, obj->size);

	seq_printf(m, "\n");
	}
	EXPORT_SYMBOL_GPL(drm_gem_cma_describe);
	#endif