drivers/gpu/drm/gma500/gem.c - maze/linux - Git at Google

 /*
  *  psb GEM interface
  *
  * Copyright (c) 2011, Intel Corporation.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope 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.
  *
  * You should have received a copy of the GNU General Public License along with
  * this program; if not, write to the Free Software Foundation, Inc.,
  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Authors: Alan Cox
  *
  * TODO:
  *	-	we need to work out if the MMU is relevant (eg for
  *		accelerated operations on a GEM object)
  */

 #include <drm/drmP.h>
 #include <drm/drm.h>
 #include "gma_drm.h"
 #include "psb_drv.h"

 int psb_gem_init_object(struct drm_gem_object *obj)
 {
 	return -EINVAL;
 }

 void psb_gem_free_object(struct drm_gem_object *obj)
 {
 	struct gtt_range *gtt = container_of(obj, struct gtt_range, gem);
 	drm_gem_object_release_wrap(obj);
 	/* This must occur last as it frees up the memory of the GEM object */
 	psb_gtt_free_range(obj->dev, gtt);
 }

 int psb_gem_get_aperture(struct drm_device *dev, void *data,
 				struct drm_file *file)
 {
 	return -EINVAL;
 }

 /**
  *	psb_gem_dumb_map_gtt	-	buffer mapping for dumb interface
  *	@file: our drm client file
  *	@dev: drm device
  *	@handle: GEM handle to the object (from dumb_create)
  *
  *	Do the necessary setup to allow the mapping of the frame buffer
  *	into user memory. We don't have to do much here at the moment.
  */
 int psb_gem_dumb_map_gtt(struct drm_file *file, struct drm_device *dev,
 			 uint32_t handle, uint64_t *offset)
 {
 	int ret = 0;
 	struct drm_gem_object *obj;

 	if (!(dev->driver->driver_features & DRIVER_GEM))
 		return -ENODEV;

 	mutex_lock(&dev->struct_mutex);

 	/* GEM does all our handle to object mapping */
 	obj = drm_gem_object_lookup(dev, file, handle);
 	if (obj == NULL) {
 		ret = -ENOENT;
 		goto unlock;
 	}
 	/* What validation is needed here ? */

 	/* Make it mmapable */
 	if (!obj->map_list.map) {
 		ret = gem_create_mmap_offset(obj);
 		if (ret)
 			goto out;
 	}
 	/* GEM should really work out the hash offsets for us */
 	*offset = (u64)obj->map_list.hash.key << PAGE_SHIFT;
 out:
 	drm_gem_object_unreference(obj);
 unlock:
 	mutex_unlock(&dev->struct_mutex);
 	return ret;
 }

 /**
  *	psb_gem_create		-	create a mappable object
  *	@file: the DRM file of the client
  *	@dev: our device
  *	@size: the size requested
  *	@handlep: returned handle (opaque number)
  *
  *	Create a GEM object, fill in the boilerplate and attach a handle to
  *	it so that userspace can speak about it. This does the core work
  *	for the various methods that do/will create GEM objects for things
  */
 static int psb_gem_create(struct drm_file *file,
 	struct drm_device *dev, uint64_t size, uint32_t *handlep)
 {
 	struct gtt_range *r;
 	int ret;
 	u32 handle;

 	size = roundup(size, PAGE_SIZE);

 	/* Allocate our object - for now a direct gtt range which is not
 	   stolen memory backed */
 	r = psb_gtt_alloc_range(dev, size, "gem", 0);
 	if (r == NULL) {
 		dev_err(dev->dev, "no memory for %lld byte GEM object\n", size);
 		return -ENOSPC;
 	}
 	/* Initialize the extra goodies GEM needs to do all the hard work */
 	if (drm_gem_object_init(dev, &r->gem, size) != 0) {
 		psb_gtt_free_range(dev, r);
 		/* GEM doesn't give an error code so use -ENOMEM */
 		dev_err(dev->dev, "GEM init failed for %lld\n", size);
 		return -ENOMEM;
 	}
 	/* Limit the object to 32bit mappings */
 	mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32);
 	/* Give the object a handle so we can carry it more easily */
 	ret = drm_gem_handle_create(file, &r->gem, &handle);
 	if (ret) {
 		dev_err(dev->dev, "GEM handle failed for %p, %lld\n",
 							&r->gem, size);
 		drm_gem_object_release(&r->gem);
 		psb_gtt_free_range(dev, r);
 		return ret;
 	}
 	/* We have the initial and handle reference but need only one now */
 	drm_gem_object_unreference(&r->gem);
 	*handlep = handle;
 	return 0;
 }

 /**
  *	psb_gem_dumb_create	-	create a dumb buffer
  *	@drm_file: our client file
  *	@dev: our device
  *	@args: the requested arguments copied from userspace
  *
  *	Allocate a buffer suitable for use for a frame buffer of the
  *	form described by user space. Give userspace a handle by which
  *	to reference it.
  */
 int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 			struct drm_mode_create_dumb *args)
 {
 	args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64);
 	args->size = args->pitch * args->height;
 	return psb_gem_create(file, dev, args->size, &args->handle);
 }

 /**
  *	psb_gem_dumb_destroy	-	destroy a dumb buffer
  *	@file: client file
  *	@dev: our DRM device
  *	@handle: the object handle
  *
  *	Destroy a handle that was created via psb_gem_dumb_create, at least
  *	we hope it was created that way. i915 seems to assume the caller
  *	does the checking but that might be worth review ! FIXME
  */
 int psb_gem_dumb_destroy(struct drm_file *file, struct drm_device *dev,
 			uint32_t handle)
 {
 	/* No special work needed, drop the reference and see what falls out */
 	return drm_gem_handle_delete(file, handle);
 }

 /**
  *	psb_gem_fault		-	pagefault handler for GEM objects
  *	@vma: the VMA of the GEM object
  *	@vmf: fault detail
  *
  *	Invoked when a fault occurs on an mmap of a GEM managed area. GEM
  *	does most of the work for us including the actual map/unmap calls
  *	but we need to do the actual page work.
  *
  *	This code eventually needs to handle faulting objects in and out
  *	of the GTT and repacking it when we run out of space. We can put
  *	that off for now and for our simple uses
  *
  *	The VMA was set up by GEM. In doing so it also ensured that the
  *	vma->vm_private_data points to the GEM object that is backing this
  *	mapping.
  */
 int psb_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct drm_gem_object *obj;
 	struct gtt_range *r;
 	int ret;
 	unsigned long pfn;
 	pgoff_t page_offset;
 	struct drm_device *dev;
 	struct drm_psb_private *dev_priv;

 	obj = vma->vm_private_data;	/* GEM object */
 	dev = obj->dev;
 	dev_priv = dev->dev_private;

 	r = container_of(obj, struct gtt_range, gem);	/* Get the gtt range */

 	/* Make sure we don't parallel update on a fault, nor move or remove
 	   something from beneath our feet */
 	mutex_lock(&dev->struct_mutex);

 	/* For now the mmap pins the object and it stays pinned. As things
 	   stand that will do us no harm */
 	if (r->mmapping == 0) {
 		ret = psb_gtt_pin(r);
 		if (ret < 0) {
 			dev_err(dev->dev, "gma500: pin failed: %d\n", ret);
 			goto fail;
 		}
 		r->mmapping = 1;
 	}

 	/* Page relative to the VMA start - we must calculate this ourselves
 	   because vmf->pgoff is the fake GEM offset */
 	page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start)
 				>> PAGE_SHIFT;

 	/* CPU view of the page, don't go via the GART for CPU writes */
 	if (r->stolen)
 		pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT;
 	else
 		pfn = page_to_pfn(r->pages[page_offset]);
 	ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);

 fail:
 	mutex_unlock(&dev->struct_mutex);
 	switch (ret) {
 	case 0:
 	case -ERESTARTSYS:
 	case -EINTR:
 		return VM_FAULT_NOPAGE;
 	case -ENOMEM:
 		return VM_FAULT_OOM;
 	default:
 		return VM_FAULT_SIGBUS;
 	}
 }

 static int psb_gem_create_stolen(struct drm_file *file, struct drm_device *dev,
 						int size, u32 *handle)
 {
 	struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1);
 	if (gtt == NULL)
 		return -ENOMEM;
 	if (drm_gem_private_object_init(dev, &gtt->gem, size) != 0)
 		goto free_gtt;
 	if (drm_gem_handle_create(file, &gtt->gem, handle) == 0)
 		return 0;
 free_gtt:
 	psb_gtt_free_range(dev, gtt);
 	return -ENOMEM;
 }

 /*
  *	GEM interfaces for our specific client
  */
 int psb_gem_create_ioctl(struct drm_device *dev, void *data,
 					struct drm_file *file)
 {
 	struct drm_psb_gem_create *args = data;
 	int ret;
 	if (args->flags & GMA_GEM_CREATE_STOLEN) {
 		ret = psb_gem_create_stolen(file, dev, args->size,
 							&args->handle);
 		if (ret == 0)
 			return 0;
 		/* Fall throguh */
 		args->flags &= ~GMA_GEM_CREATE_STOLEN;
 	}
 	return psb_gem_create(file, dev, args->size, &args->handle);
 }

 int psb_gem_mmap_ioctl(struct drm_device *dev, void *data,
 					struct drm_file *file)
 {
 	struct drm_psb_gem_mmap *args = data;
 	return dev->driver->dumb_map_offset(file, dev,
 						args->handle, &args->offset);
 }
	/*
	* psb GEM interface
	*
	* Copyright (c) 2011, Intel Corporation.
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope 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.
	*
	* You should have received a copy of the GNU General Public License along with
	* this program; if not, write to the Free Software Foundation, Inc.,
	* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Authors: Alan Cox
	*
	* TODO:
	* - we need to work out if the MMU is relevant (eg for
	* accelerated operations on a GEM object)
	*/

	#include <drm/drmP.h>
	#include <drm/drm.h>
	#include "gma_drm.h"
	#include "psb_drv.h"

	int psb_gem_init_object(struct drm_gem_object *obj)
	{
	return -EINVAL;
	}

	void psb_gem_free_object(struct drm_gem_object *obj)
	{
	struct gtt_range *gtt = container_of(obj, struct gtt_range, gem);
	drm_gem_object_release_wrap(obj);
	/* This must occur last as it frees up the memory of the GEM object */
	psb_gtt_free_range(obj->dev, gtt);
	}

	int psb_gem_get_aperture(struct drm_device dev, void data,
	struct drm_file *file)
	{
	return -EINVAL;
	}

	/**
	* psb_gem_dumb_map_gtt - buffer mapping for dumb interface
	* @file: our drm client file
	* @dev: drm device
	* @handle: GEM handle to the object (from dumb_create)
	*
	* Do the necessary setup to allow the mapping of the frame buffer
	* into user memory. We don't have to do much here at the moment.
	*/
	int psb_gem_dumb_map_gtt(struct drm_file file, struct drm_device dev,
	uint32_t handle, uint64_t *offset)
	{
	int ret = 0;
	struct drm_gem_object *obj;

	if (!(dev->driver->driver_features & DRIVER_GEM))
	return -ENODEV;

	mutex_lock(&dev->struct_mutex);

	/* GEM does all our handle to object mapping */
	obj = drm_gem_object_lookup(dev, file, handle);
	if (obj == NULL) {
	ret = -ENOENT;
	goto unlock;
	}
	/* What validation is needed here ? */

	/* Make it mmapable */
	if (!obj->map_list.map) {
	ret = gem_create_mmap_offset(obj);
	if (ret)
	goto out;
	}
	/* GEM should really work out the hash offsets for us */
	*offset = (u64)obj->map_list.hash.key << PAGE_SHIFT;
	out:
	drm_gem_object_unreference(obj);
	unlock:
	mutex_unlock(&dev->struct_mutex);
	return ret;
	}

	/**
	* psb_gem_create - create a mappable object
	* @file: the DRM file of the client
	* @dev: our device
	* @size: the size requested
	* @handlep: returned handle (opaque number)
	*
	* Create a GEM object, fill in the boilerplate and attach a handle to
	* it so that userspace can speak about it. This does the core work
	* for the various methods that do/will create GEM objects for things
	*/
	static int psb_gem_create(struct drm_file *file,
	struct drm_device dev, uint64_t size, uint32_t handlep)
	{
	struct gtt_range *r;
	int ret;
	u32 handle;

	size = roundup(size, PAGE_SIZE);

	/* Allocate our object - for now a direct gtt range which is not
	stolen memory backed */
	r = psb_gtt_alloc_range(dev, size, "gem", 0);
	if (r == NULL) {
	dev_err(dev->dev, "no memory for %lld byte GEM object\n", size);
	return -ENOSPC;
	}
	/* Initialize the extra goodies GEM needs to do all the hard work */
	if (drm_gem_object_init(dev, &r->gem, size) != 0) {
	psb_gtt_free_range(dev, r);
	/* GEM doesn't give an error code so use -ENOMEM */
	dev_err(dev->dev, "GEM init failed for %lld\n", size);
	return -ENOMEM;
	}
	/* Limit the object to 32bit mappings */
	mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL \| __GFP_DMA32);
	/* Give the object a handle so we can carry it more easily */
	ret = drm_gem_handle_create(file, &r->gem, &handle);
	if (ret) {
	dev_err(dev->dev, "GEM handle failed for %p, %lld\n",
	&r->gem, size);
	drm_gem_object_release(&r->gem);
	psb_gtt_free_range(dev, r);
	return ret;
	}
	/* We have the initial and handle reference but need only one now */
	drm_gem_object_unreference(&r->gem);
	*handlep = handle;
	return 0;
	}

	/**
	* psb_gem_dumb_create - create a dumb buffer
	* @drm_file: our client file
	* @dev: our device
	* @args: the requested arguments copied from userspace
	*
	* Allocate a buffer suitable for use for a frame buffer of the
	* form described by user space. Give userspace a handle by which
	* to reference it.
	*/
	int psb_gem_dumb_create(struct drm_file file, struct drm_device dev,
	struct drm_mode_create_dumb *args)
	{
	args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64);
	args->size = args->pitch * args->height;
	return psb_gem_create(file, dev, args->size, &args->handle);
	}

	/**
	* psb_gem_dumb_destroy - destroy a dumb buffer
	* @file: client file
	* @dev: our DRM device
	* @handle: the object handle
	*
	* Destroy a handle that was created via psb_gem_dumb_create, at least
	* we hope it was created that way. i915 seems to assume the caller
	* does the checking but that might be worth review ! FIXME
	*/
	int psb_gem_dumb_destroy(struct drm_file file, struct drm_device dev,
	uint32_t handle)
	{
	/* No special work needed, drop the reference and see what falls out */
	return drm_gem_handle_delete(file, handle);
	}

	/**
	* psb_gem_fault - pagefault handler for GEM objects
	* @vma: the VMA of the GEM object
	* @vmf: fault detail
	*
	* Invoked when a fault occurs on an mmap of a GEM managed area. GEM
	* does most of the work for us including the actual map/unmap calls
	* but we need to do the actual page work.
	*
	* This code eventually needs to handle faulting objects in and out
	* of the GTT and repacking it when we run out of space. We can put
	* that off for now and for our simple uses
	*
	* The VMA was set up by GEM. In doing so it also ensured that the
	* vma->vm_private_data points to the GEM object that is backing this
	* mapping.
	*/
	int psb_gem_fault(struct vm_area_struct vma, struct vm_fault vmf)
	{
	struct drm_gem_object *obj;
	struct gtt_range *r;
	int ret;
	unsigned long pfn;
	pgoff_t page_offset;
	struct drm_device *dev;
	struct drm_psb_private *dev_priv;

	obj = vma->vm_private_data; /* GEM object */
	dev = obj->dev;
	dev_priv = dev->dev_private;

	r = container_of(obj, struct gtt_range, gem); /* Get the gtt range */

	/* Make sure we don't parallel update on a fault, nor move or remove
	something from beneath our feet */
	mutex_lock(&dev->struct_mutex);

	/* For now the mmap pins the object and it stays pinned. As things
	stand that will do us no harm */
	if (r->mmapping == 0) {
	ret = psb_gtt_pin(r);
	if (ret < 0) {
	dev_err(dev->dev, "gma500: pin failed: %d\n", ret);
	goto fail;
	}
	r->mmapping = 1;
	}

	/* Page relative to the VMA start - we must calculate this ourselves
	because vmf->pgoff is the fake GEM offset */
	page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start)
	>> PAGE_SHIFT;

	/* CPU view of the page, don't go via the GART for CPU writes */
	if (r->stolen)
	pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT;
	else
	pfn = page_to_pfn(r->pages[page_offset]);
	ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);

	fail:
	mutex_unlock(&dev->struct_mutex);
	switch (ret) {
	case 0:
	case -ERESTARTSYS:
	case -EINTR:
	return VM_FAULT_NOPAGE;
	case -ENOMEM:
	return VM_FAULT_OOM;
	default:
	return VM_FAULT_SIGBUS;
	}
	}

	static int psb_gem_create_stolen(struct drm_file file, struct drm_device dev,
	int size, u32 *handle)
	{
	struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1);
	if (gtt == NULL)
	return -ENOMEM;
	if (drm_gem_private_object_init(dev, &gtt->gem, size) != 0)
	goto free_gtt;
	if (drm_gem_handle_create(file, &gtt->gem, handle) == 0)
	return 0;
	free_gtt:
	psb_gtt_free_range(dev, gtt);
	return -ENOMEM;
	}

	/*
	* GEM interfaces for our specific client
	*/
	int psb_gem_create_ioctl(struct drm_device dev, void data,
	struct drm_file *file)
	{
	struct drm_psb_gem_create *args = data;
	int ret;
	if (args->flags & GMA_GEM_CREATE_STOLEN) {
	ret = psb_gem_create_stolen(file, dev, args->size,
	&args->handle);
	if (ret == 0)
	return 0;
	/* Fall throguh */
	args->flags &= ~GMA_GEM_CREATE_STOLEN;
	}
	return psb_gem_create(file, dev, args->size, &args->handle);
	}

	int psb_gem_mmap_ioctl(struct drm_device dev, void data,
	struct drm_file *file)
	{
	struct drm_psb_gem_mmap *args = data;
	return dev->driver->dumb_map_offset(file, dev,
	args->handle, &args->offset);
	}