drm_vm.h

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

/* drm_vm.h -- Memory mapping for DRM -*- linux-c -*-
 * Created: Mon Jan  4 08:58:31 1999 by [e-mail]
 *
 * 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.
 *
 * Authors:
 *    Rickard E. (Rik) Faith <[e-mail]>
 *    Gareth Hughes <[e-mail]>
 */

#define __NO_VERSION__
#include "drmP.h"

struct vm_operations_struct   DRM(vm_ops) = {
	nopage:	 DRM(vm_nopage),
	open:	 DRM(vm_open),
	close:	 DRM(vm_close),
};

struct vm_operations_struct   DRM(vm_shm_ops) = {
	nopage:	 DRM(vm_shm_nopage),
	open:	 DRM(vm_open),
	close:	 DRM(vm_shm_close),
};

struct vm_operations_struct   DRM(vm_dma_ops) = {
	nopage:	 DRM(vm_dma_nopage),
	open:	 DRM(vm_open),
	close:	 DRM(vm_close),
};

struct vm_operations_struct   DRM(vm_sg_ops) = {
	nopage:  DRM(vm_sg_nopage),
	open:    DRM(vm_open),
	close:   DRM(vm_close),
};

#if LINUX_VERSION_CODE < 0x020317
unsigned long DRM(vm_nopage)(struct vm_area_struct *vma,
			     unsigned long address,
			     int unused)
#else
				/* Return type changed in 2.3.23 */
struct page *DRM(vm_nopage)(struct vm_area_struct *vma,
			    unsigned long address,
			    int unused)
#endif
{
#if __REALLY_HAVE_AGP
	drm_file_t *priv  = vma->vm_file->private_data;
	drm_device_t *dev = priv->dev;
	drm_map_t *map    = NULL;
	drm_map_list_t  *r_list;
	struct list_head *list;

	/*
         * Find the right map
         */

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

	list_for_each(list, &dev->maplist->head) {
		r_list = (drm_map_list_t *)list;
		map = r_list->map;
		if (!map) continue;
		if (map->offset == VM_OFFSET(vma)) break;
	}

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

#if __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
                 */
		for(agpmem = dev->agp->memory; agpmem; agpmem = agpmem->next) {
			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;
		agpmem->memory->memory[offset] &= dev->agp->page_mask;
		page = virt_to_page(__va(agpmem->memory->memory[offset]));
		get_page(page);

		DRM_DEBUG("baddr = 0x%lx page = 0x%p, offset = 0x%lx\n",
			  baddr, __va(agpmem->memory->memory[offset]), offset);

#if LINUX_VERSION_CODE < 0x020317
		return page_address(page);
#else
		return page;
#endif
        }
vm_nopage_error:
#endif /* __REALLY_HAVE_AGP */

	return NOPAGE_SIGBUS;		/* Disallow mremap */
}

#if LINUX_VERSION_CODE < 0x020317
unsigned long DRM(vm_shm_nopage)(struct vm_area_struct *vma,
				 unsigned long address,
				 int unused)
#else
				/* Return type changed in 2.3.23 */
struct page *DRM(vm_shm_nopage)(struct vm_area_struct *vma,
				unsigned long address,
				int unused)
#endif
{
#if LINUX_VERSION_CODE >= 0x020300
	drm_map_t	 *map	 = (drm_map_t *)vma->vm_private_data;
#else
	drm_map_t	 *map	 = (drm_map_t *)vma->vm_pte;
#endif
	unsigned long	 offset;
	unsigned long	 i;
	pgd_t		 *pgd;
	pmd_t		 *pmd;
	pte_t		 *pte;
	struct page	 *page;

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

	offset	 = address - vma->vm_start;
	i = (unsigned long)map->handle + offset;
	/* We have to walk page tables here because we need large SAREA's, and
	 * they need to be virtually contiguous in kernel space.
	 */
	pgd = pgd_offset_k( i );
	if( !pgd_present( *pgd ) ) return NOPAGE_OOM;
	pmd = pmd_offset( pgd, i );
	if( !pmd_present( *pmd ) ) return NOPAGE_OOM;
	pte = pte_offset( pmd, i );
	if( !pte_present( *pte ) ) return NOPAGE_OOM;

	page = pte_page(*pte);
	get_page(page);

	DRM_DEBUG("shm_nopage 0x%lx\n", address);
#if LINUX_VERSION_CODE < 0x020317
	return page_address(page);
#else
	return page;
#endif
}

/* Special close routine which deletes map information if we are the last
 * person to close a mapping and its not in the global maplist.
 */

void DRM(vm_shm_close)(struct vm_area_struct *vma)
{
	drm_file_t	*priv	= vma->vm_file->private_data;
	drm_device_t	*dev	= priv->dev;
	drm_vma_entry_t *pt, *prev, *next;
	drm_map_t *map;
	drm_map_list_t *r_list;
	struct list_head *list;
	int found_maps = 0;

	DRM_DEBUG("0x%08lx,0x%08lx\n",
		  vma->vm_start, vma->vm_end - vma->vm_start);
#if LINUX_VERSION_CODE < 0x020333
	MOD_DEC_USE_COUNT; /* Needed before Linux 2.3.51 */
#endif
	atomic_dec(&dev->vma_count);

#if LINUX_VERSION_CODE >= 0x020300
	map = vma->vm_private_data;
#else
	map = vma->vm_pte;
#endif

	down(&dev->struct_sem);
	for (pt = dev->vmalist, prev = NULL; pt; pt = next) {
		next = pt->next;
#if LINUX_VERSION_CODE >= 0x020300
		if (pt->vma->vm_private_data == map) found_maps++;
#else
		if (pt->vma->vm_pte == map) found_maps++;
#endif
		if (pt->vma == vma) {
			if (prev) {
				prev->next = pt->next;
			} else {
				dev->vmalist = pt->next;
			}
			DRM(free)(pt, sizeof(*pt), DRM_MEM_VMAS);
		} else {
			prev = pt;
		}
	}
	/* We were the only map that was found */
	if(found_maps == 1 &&
	   map->flags & _DRM_REMOVABLE) {
		/* Check to see if we are in the maplist, if we are not, then
		 * we delete this mappings information.
		 */
		found_maps = 0;
		list = &dev->maplist->head;
		list_for_each(list, &dev->maplist->head) {
			r_list = (drm_map_list_t *) list;
			if (r_list->map == map) found_maps++;
		}

		if(!found_maps) {
			switch (map->type) {
			case _DRM_REGISTERS:
			case _DRM_FRAME_BUFFER:
#if __REALLY_HAVE_MTRR
				if (map->mtrr >= 0) {
					int retcode;
					retcode = mtrr_del(map->mtrr,
							   map->offset,
							   map->size);
					DRM_DEBUG("mtrr_del = %d\n", retcode);
				}
#endif
				DRM(ioremapfree)(map->handle, map->size);
				break;
			case _DRM_SHM:
				vfree(map->handle);
				break;
			case _DRM_AGP:
			case _DRM_SCATTER_GATHER:
				break;
			}
			DRM(free)(map, sizeof(*map), DRM_MEM_MAPS);
		}
	}
	up(&dev->struct_sem);
}

#if LINUX_VERSION_CODE < 0x020317
unsigned long DRM(vm_dma_nopage)(struct vm_area_struct *vma,
				 unsigned long address,
				 int unused)
#else
				/* Return type changed in 2.3.23 */
struct page *DRM(vm_dma_nopage)(struct vm_area_struct *vma,
				unsigned long address,
				int unused)
#endif
{
	drm_file_t	 *priv	 = vma->vm_file->private_data;
	drm_device_t	 *dev	 = priv->dev;
	drm_device_dma_t *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_OOM ; /* Nothing allocated */