linux-core/drm_vm_nopage_compat.c - libdrm-imx - Git at Google

 /**
  * \file drm_vm.c
  * Memory mapping for DRM
  *
  * \author Rickard E. (Rik) Faith <faith@valinux.com>
  * \author Gareth Hughes <gareth@valinux.com>
  */

 /*
  * Created: Mon Jan  4 08:58:31 1999 by faith@valinux.com
  *
  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  * All Rights Reserved.
  *
  * 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
  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS 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.
  */

 #include "drmP.h"

 #ifdef DRM_VM_NOPAGE
 /**
  * \c nopage method for AGP virtual memory.
  *
  * \param vma virtual memory area.
  * \param address access address.
  * \return pointer to the page structure.
  *
  * Find the right map and if it's AGP memory find the real physical page to
  * map, get the page, increment the use count and return it.
  */
 #if __OS_HAS_AGP
 static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
 						unsigned long address)
 {
 	struct drm_file *priv = vma->vm_file->private_data;
 	struct drm_device *dev = priv->minor->dev;
 	struct drm_map *map = NULL;
 	struct drm_map_list *r_list;
 	struct drm_hash_item *hash;

 	/*
 	 * Find the right map
 	 */
 	if (!drm_core_has_AGP(dev))
 		goto vm_nopage_error;

 	if (!dev->agp || !dev->agp->cant_use_aperture)
 		goto vm_nopage_error;

 	if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
 		goto vm_nopage_error;

 	r_list = drm_hash_entry(hash, struct drm_map_list, hash);
 	map = r_list->map;

 	if (map && map->type == _DRM_AGP) {
 		unsigned long offset = address - vma->vm_start;
 		unsigned long baddr = map->offset + offset;
 		struct drm_agp_mem *agpmem;
 		struct page *page;

 #ifdef __alpha__
 		/*
 		 * Adjust to a bus-relative address
 		 */
 		baddr -= dev->hose->mem_space->start;
 #endif

 		/*
 		 * It's AGP memory - find the real physical page to map
 		 */
 		list_for_each_entry(agpmem, &dev->agp->memory, head) {
 			if (agpmem->bound <= baddr &&
 			    agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
 				break;
 		}

 		if (!agpmem)
 			goto vm_nopage_error;

 		/*
 		 * Get the page, inc the use count, and return it
 		 */
 		offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
 		page = virt_to_page(__va(agpmem->memory->memory[offset]));
 		get_page(page);

 #if 0
 		/* page_count() not defined everywhere */
 		DRM_DEBUG
 		    ("baddr = 0x%lx page = 0x%p, offset = 0x%lx, count=%d\n",
 		     baddr, __va(agpmem->memory->memory[offset]), offset,
 		     page_count(page));
 #endif

 		return page;
 	}
       vm_nopage_error:
 	return NOPAGE_SIGBUS;	/* Disallow mremap */
 }
 #else				/* __OS_HAS_AGP */
 static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
 						unsigned long address)
 {
 	return NOPAGE_SIGBUS;
 }
 #endif				/* __OS_HAS_AGP */

 /**
  * \c nopage method for shared virtual memory.
  *
  * \param vma virtual memory area.
  * \param address access address.
  * \return pointer to the page structure.
  *
  * Get the mapping, find the real physical page to map, get the page, and
  * return it.
  */
 static __inline__ struct page *drm_do_vm_shm_nopage(struct vm_area_struct *vma,
 						    unsigned long address)
 {
 	struct drm_map *map = (struct drm_map *) vma->vm_private_data;
 	unsigned long offset;
 	unsigned long i;
 	struct page *page;

 	if (address > vma->vm_end)
 		return NOPAGE_SIGBUS;	/* Disallow mremap */
 	if (!map)
 		return NOPAGE_SIGBUS;	/* Nothing allocated */

 	offset = address - vma->vm_start;
 	i = (unsigned long)map->handle + offset;
 	page = vmalloc_to_page((void *)i);
 	if (!page)
 		return NOPAGE_SIGBUS;
 	get_page(page);

 	DRM_DEBUG("0x%lx\n", address);
 	return page;
 }

 /**
  * \c nopage method for DMA virtual memory.
  *
  * \param vma virtual memory area.
  * \param address access address.
  * \return pointer to the page structure.
  *
  * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
  */
 static __inline__ struct page *drm_do_vm_dma_nopage(struct vm_area_struct *vma,
 						    unsigned long address)
 {
 	struct drm_file *priv = vma->vm_file->private_data;
 	struct drm_device *dev = priv->minor->dev;
 	struct drm_device_dma *dma = dev->dma;
 	unsigned long offset;
 	unsigned long page_nr;
 	struct page *page;

 	if (!dma)
 		return NOPAGE_SIGBUS;	/* Error */
 	if (address > vma->vm_end)
 		return NOPAGE_SIGBUS;	/* Disallow mremap */
 	if (!dma->pagelist)
 		return NOPAGE_SIGBUS;	/* Nothing allocated */

 	offset = address - vma->vm_start;	/* vm_[pg]off[set] should be 0 */
 	page_nr = offset >> PAGE_SHIFT;
 	page = virt_to_page((dma->pagelist[page_nr] + (offset & (~PAGE_MASK))));

 	get_page(page);

 	DRM_DEBUG("0x%lx (page %lu)\n", address, page_nr);
 	return page;
 }

 /**
  * \c nopage method for scatter-gather virtual memory.
  *
  * \param vma virtual memory area.
  * \param address access address.
  * \return pointer to the page structure.
  *
  * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
  */
 static __inline__ struct page *drm_do_vm_sg_nopage(struct vm_area_struct *vma,
 						   unsigned long address)
 {
 	struct drm_map *map = (struct drm_map *) vma->vm_private_data;
 	struct drm_file *priv = vma->vm_file->private_data;
 	struct drm_device *dev = priv->minor->dev;
 	struct drm_sg_mem *entry = dev->sg;
 	unsigned long offset;
 	unsigned long map_offset;
 	unsigned long page_offset;
 	struct page *page;

 	DRM_DEBUG("\n");
 	if (!entry)
 		return NOPAGE_SIGBUS;	/* Error */
 	if (address > vma->vm_end)
 		return NOPAGE_SIGBUS;	/* Disallow mremap */
 	if (!entry->pagelist)
 		return NOPAGE_SIGBUS;	/* Nothing allocated */

 	offset = address - vma->vm_start;
 	map_offset = map->offset - (unsigned long)dev->sg->virtual;
 	page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
 	page = entry->pagelist[page_offset];
 	get_page(page);

 	return page;
 }


 struct page *drm_vm_nopage(struct vm_area_struct *vma,
 			   unsigned long address, int *type)
 {
 	if (type)
 		*type = VM_FAULT_MINOR;
 	return drm_do_vm_nopage(vma, address);
 }

 struct page *drm_vm_shm_nopage(struct vm_area_struct *vma,
 			       unsigned long address, int *type)
 {
 	if (type)
 		*type = VM_FAULT_MINOR;
 	return drm_do_vm_shm_nopage(vma, address);
 }

 struct page *drm_vm_dma_nopage(struct vm_area_struct *vma,
 			       unsigned long address, int *type)
 {
 	if (type)
 		*type = VM_FAULT_MINOR;
 	return drm_do_vm_dma_nopage(vma, address);
 }

 struct page *drm_vm_sg_nopage(struct vm_area_struct *vma,
 			      unsigned long address, int *type)
 {
 	if (type)
 		*type = VM_FAULT_MINOR;
 	return drm_do_vm_sg_nopage(vma, address);
 }
 #endif
	/**
	* \file drm_vm.c
	* Memory mapping for DRM
	*
	* \author Rickard E. (Rik) Faith <faith@valinux.com>
	* \author Gareth Hughes <gareth@valinux.com>
	*/

	/*
	* Created: Mon Jan 4 08:58:31 1999 by faith@valinux.com
	*
	* Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
	* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
	* All Rights Reserved.
	*
	* 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
	* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS 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.
	*/

	#include "drmP.h"

	#ifdef DRM_VM_NOPAGE
	/**
	* \c nopage method for AGP virtual memory.
	*
	* \param vma virtual memory area.
	* \param address access address.
	* \return pointer to the page structure.
	*
	* Find the right map and if it's AGP memory find the real physical page to
	* map, get the page, increment the use count and return it.
	*/
	#if __OS_HAS_AGP
	static __inline__ struct page drm_do_vm_nopage(struct vm_area_struct vma,
	unsigned long address)
	{
	struct drm_file *priv = vma->vm_file->private_data;
	struct drm_device *dev = priv->minor->dev;
	struct drm_map *map = NULL;
	struct drm_map_list *r_list;
	struct drm_hash_item *hash;

	/*
	* Find the right map
	*/
	if (!drm_core_has_AGP(dev))
	goto vm_nopage_error;

	if (!dev->agp \|\| !dev->agp->cant_use_aperture)
	goto vm_nopage_error;

	if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
	goto vm_nopage_error;

	r_list = drm_hash_entry(hash, struct drm_map_list, hash);
	map = r_list->map;

	if (map && map->type == _DRM_AGP) {
	unsigned long offset = address - vma->vm_start;
	unsigned long baddr = map->offset + offset;
	struct drm_agp_mem *agpmem;
	struct page *page;

	#ifdef __alpha__
	/*
	* Adjust to a bus-relative address
	*/
	baddr -= dev->hose->mem_space->start;
	#endif

	/*
	* It's AGP memory - find the real physical page to map
	*/
	list_for_each_entry(agpmem, &dev->agp->memory, head) {
	if (agpmem->bound <= baddr &&
	agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
	break;
	}

	if (!agpmem)
	goto vm_nopage_error;

	/*
	* Get the page, inc the use count, and return it
	*/
	offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
	page = virt_to_page(__va(agpmem->memory->memory[offset]));
	get_page(page);

	#if 0
	/* page_count() not defined everywhere */
	DRM_DEBUG
	("baddr = 0x%lx page = 0x%p, offset = 0x%lx, count=%d\n",
	baddr, __va(agpmem->memory->memory[offset]), offset,
	page_count(page));
	#endif

	return page;
	}
	vm_nopage_error:
	return NOPAGE_SIGBUS; /* Disallow mremap */
	}
	#else /* __OS_HAS_AGP */
	static __inline__ struct page drm_do_vm_nopage(struct vm_area_struct vma,
	unsigned long address)
	{
	return NOPAGE_SIGBUS;
	}
	#endif /* __OS_HAS_AGP */

	/**
	* \c nopage method for shared virtual memory.
	*
	* \param vma virtual memory area.
	* \param address access address.
	* \return pointer to the page structure.
	*
	* Get the mapping, find the real physical page to map, get the page, and
	* return it.
	*/
	static __inline__ struct page drm_do_vm_shm_nopage(struct vm_area_struct vma,
	unsigned long address)
	{
	struct drm_map map = (struct drm_map ) vma->vm_private_data;
	unsigned long offset;
	unsigned long i;
	struct page *page;

	if (address > vma->vm_end)
	return NOPAGE_SIGBUS; /* Disallow mremap */
	if (!map)
	return NOPAGE_SIGBUS; /* Nothing allocated */

	offset = address - vma->vm_start;
	i = (unsigned long)map->handle + offset;
	page = vmalloc_to_page((void *)i);
	if (!page)
	return NOPAGE_SIGBUS;
	get_page(page);

	DRM_DEBUG("0x%lx\n", address);
	return page;
	}

	/**
	* \c nopage method for DMA virtual memory.
	*
	* \param vma virtual memory area.
	* \param address access address.
	* \return pointer to the page structure.
	*
	* Determine the page number from the page offset and get it from drm_device_dma::pagelist.
	*/
	static __inline__ struct page drm_do_vm_dma_nopage(struct vm_area_struct vma,
	unsigned long address)
	{
	struct drm_file *priv = vma->vm_file->private_data;
	struct drm_device *dev = priv->minor->dev;
	struct drm_device_dma *dma = dev->dma;
	unsigned long offset;
	unsigned long page_nr;
	struct page *page;

	if (!dma)
	return NOPAGE_SIGBUS; /* Error */
	if (address > vma->vm_end)
	return NOPAGE_SIGBUS; /* Disallow mremap */
	if (!dma->pagelist)
	return NOPAGE_SIGBUS; /* Nothing allocated */

	offset = address - vma->vm_start; /* vm_[pg]off[set] should be 0 */
	page_nr = offset >> PAGE_SHIFT;
	page = virt_to_page((dma->pagelist[page_nr] + (offset & (~PAGE_MASK))));

	get_page(page);

	DRM_DEBUG("0x%lx (page %lu)\n", address, page_nr);
	return page;
	}

	/**
	* \c nopage method for scatter-gather virtual memory.
	*
	* \param vma virtual memory area.
	* \param address access address.
	* \return pointer to the page structure.
	*
	* Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
	*/
	static __inline__ struct page drm_do_vm_sg_nopage(struct vm_area_struct vma,
	unsigned long address)
	{
	struct drm_map map = (struct drm_map ) vma->vm_private_data;
	struct drm_file *priv = vma->vm_file->private_data;
	struct drm_device *dev = priv->minor->dev;
	struct drm_sg_mem *entry = dev->sg;
	unsigned long offset;
	unsigned long map_offset;
	unsigned long page_offset;
	struct page *page;

	DRM_DEBUG("\n");
	if (!entry)
	return NOPAGE_SIGBUS; /* Error */
	if (address > vma->vm_end)
	return NOPAGE_SIGBUS; /* Disallow mremap */
	if (!entry->pagelist)
	return NOPAGE_SIGBUS; /* Nothing allocated */

	offset = address - vma->vm_start;
	map_offset = map->offset - (unsigned long)dev->sg->virtual;
	page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
	page = entry->pagelist[page_offset];
	get_page(page);

	return page;
	}


	struct page drm_vm_nopage(struct vm_area_struct vma,
	unsigned long address, int *type)
	{
	if (type)
	*type = VM_FAULT_MINOR;
	return drm_do_vm_nopage(vma, address);
	}

	struct page drm_vm_shm_nopage(struct vm_area_struct vma,
	unsigned long address, int *type)
	{
	if (type)
	*type = VM_FAULT_MINOR;
	return drm_do_vm_shm_nopage(vma, address);
	}

	struct page drm_vm_dma_nopage(struct vm_area_struct vma,
	unsigned long address, int *type)
	{
	if (type)
	*type = VM_FAULT_MINOR;
	return drm_do_vm_dma_nopage(vma, address);
	}

	struct page drm_vm_sg_nopage(struct vm_area_struct vma,
	unsigned long address, int *type)
	{
	if (type)
	*type = VM_FAULT_MINOR;
	return drm_do_vm_sg_nopage(vma, address);
	}
	#endif