drm_bufs.c

linux-2.6.15.6

/**
 * \file drm_bufs.c
 * Generic buffer template
 *
 * \author Rickard E. (Rik) Faith <[e-mail]>
 * \author Gareth Hughes <[e-mail]>
 */

/*
 * Created: Thu Nov 23 03:10:50 2000 by [e-mail]
 *
 * Copyright 1999, 2000 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 <linux/vmalloc.h>
#include "drmP.h"

unsigned long drm_get_resource_start(drm_device_t * dev, unsigned int resource)
{
	return pci_resource_start(dev->pdev, resource);
}

EXPORT_SYMBOL(drm_get_resource_start);

unsigned long drm_get_resource_len(drm_device_t * dev, unsigned int resource)
{
	return pci_resource_len(dev->pdev, resource);
}

EXPORT_SYMBOL(drm_get_resource_len);

static drm_map_list_t *drm_find_matching_map(drm_device_t * dev,
					     drm_local_map_t * map)
{
	struct list_head *list;

	list_for_each(list, &dev->maplist->head) {
		drm_map_list_t *entry = list_entry(list, drm_map_list_t, head);
		if (entry->map && map->type == entry->map->type &&
		    entry->map->offset == map->offset) {
			return entry;
		}
	}

	return NULL;
}

/*
 * Used to allocate 32-bit handles for mappings.
 */
#define START_RANGE 0x10000000
#define END_RANGE 0x40000000

#ifdef _LP64
static __inline__ unsigned int HandleID(unsigned long lhandle,
					drm_device_t * dev)
{
	static unsigned int map32_handle = START_RANGE;
	unsigned int hash;

	if (lhandle & 0xffffffff00000000) {
		hash = map32_handle;
		map32_handle += PAGE_SIZE;
		if (map32_handle > END_RANGE)
			map32_handle = START_RANGE;
	} else
		hash = lhandle;

	while (1) {
		drm_map_list_t *_entry;
		list_for_each_entry(_entry, &dev->maplist->head, head) {
			if (_entry->user_token == hash)
				break;
		}
		if (&_entry->head == &dev->maplist->head)
			return hash;

		hash += PAGE_SIZE;
		map32_handle += PAGE_SIZE;
	}
}
#else
# define HandleID(x,dev) (unsigned int)(x)
#endif

/**
 * Ioctl to specify a range of memory that is available for mapping by a non-root process.
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg pointer to a drm_map structure.
 * \return zero on success or a negative value on error.
 *
 * Adjusts the memory offset to its absolute value according to the mapping
 * type.  Adds the map to the map list drm_device::maplist. Adds MTRR's where
 * applicable and if supported by the kernel.
 */
static int drm_addmap_core(drm_device_t * dev, unsigned int offset,
			   unsigned int size, drm_map_type_t type,
			   drm_map_flags_t flags, drm_map_list_t ** maplist)
{
	drm_map_t *map;
	drm_map_list_t *list;
	drm_dma_handle_t *dmah;

	map = drm_alloc(sizeof(*map), DRM_MEM_MAPS);
	if (!map)
		return -ENOMEM;

	map->offset = offset;
	map->size = size;
	map->flags = flags;
	map->type = type;

	/* Only allow shared memory to be removable since we only keep enough
	 * book keeping information about shared memory to allow for removal
	 * when processes fork.
	 */
	if ((map->flags & _DRM_REMOVABLE) && map->type != _DRM_SHM) {
		drm_free(map, sizeof(*map), DRM_MEM_MAPS);
		return -EINVAL;
	}
	DRM_DEBUG("offset = 0x%08lx, size = 0x%08lx, type = %d\n",
		  map->offset, map->size, map->type);
	if ((map->offset & (~PAGE_MASK)) || (map->size & (~PAGE_MASK))) {
		drm_free(map, sizeof(*map), DRM_MEM_MAPS);
		return -EINVAL;
	}
	map->mtrr = -1;
	map->handle = NULL;

	switch (map->type) {
	case _DRM_REGISTERS:
	case _DRM_FRAME_BUFFER:
#if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__)
		if (map->offset + map->size < map->offset ||
		    map->offset < virt_to_phys(high_memory)) {
			drm_free(map, sizeof(*map), DRM_MEM_MAPS);
			return -EINVAL;
		}
#endif
#ifdef __alpha__
		map->offset += dev->hose->mem_space->start;
#endif
		/* Some drivers preinitialize some maps, without the X Server
		 * needing to be aware of it.  Therefore, we just return success
		 * when the server tries to create a duplicate map.
		 */
		list = drm_find_matching_map(dev, map);
		if (list != NULL) {
			if (list->map->size != map->size) {
				DRM_DEBUG("Matching maps of type %d with "
					  "mismatched sizes, (%ld vs %ld)\n",
					  map->type, map->size,
					  list->map->size);
				list->map->size = map->size;
			}

			drm_free(map, sizeof(*map), DRM_MEM_MAPS);
			*maplist = list;
			return 0;
		}

		if (drm_core_has_MTRR(dev)) {
			if (map->type == _DRM_FRAME_BUFFER ||
			    (map->flags & _DRM_WRITE_COMBINING)) {
				map->mtrr = mtrr_add(map->offset, map->size,
						     MTRR_TYPE_WRCOMB, 1);
			}
		}
		if (map->type == _DRM_REGISTERS)
			map->handle = drm_ioremap(map->offset, map->size, dev);
		break;

	case _DRM_SHM:
		map->handle = vmalloc_32(map->size);
		DRM_DEBUG("%lu %d %p\n",
			  map->size, drm_order(map->size), map->handle);
		if (!map->handle) {
			drm_free(map, sizeof(*map), DRM_MEM_MAPS);
			return -ENOMEM;
		}
		map->offset = (unsigned long)map->handle;
		if (map->flags & _DRM_CONTAINS_LOCK) {
			/* Prevent a 2nd X Server from creating a 2nd lock */
			if (dev->lock.hw_lock != NULL) {
				vfree(map->handle);
				drm_free(map, sizeof(*map), DRM_MEM_MAPS);
				return -EBUSY;
			}
			dev->sigdata.lock = dev->lock.hw_lock = map->handle;	/* Pointer to lock */
		}
		break;
	case _DRM_AGP:
		if (drm_core_has_AGP(dev)) {
#ifdef __alpha__
			map->offset += dev->hose->mem_space->start;
#endif
			map->offset += dev->agp->base;
			map->mtrr = dev->agp->agp_mtrr;	/* for getmap */
		}
		break;
	case _DRM_SCATTER_GATHER:
		if (!dev->sg) {
			drm_free(map, sizeof(*map), DRM_MEM_MAPS);
			return -EINVAL;
		}
		map->offset += (unsigned long)dev->sg->virtual;
		break;
	case _DRM_CONSISTENT:
		/* dma_addr_t is 64bit on i386 with CONFIG_HIGHMEM64G,
		 * As we're limiting the address to 2^32-1 (or less),
		 * casting it down to 32 bits is no problem, but we
		 * need to point to a 64bit variable first. */
		dmah = drm_pci_alloc(dev, map->size, map->size, 0xffffffffUL);
		if (!dmah) {
			drm_free(map, sizeof(*map), DRM_MEM_MAPS);
			return -ENOMEM;
		}
		map->handle = dmah->vaddr;
		map->offset = (unsigned long)dmah->busaddr;
		kfree(dmah);
		break;
	default:
		drm_free(map, sizeof(*map), DRM_MEM_MAPS);
		return -EINVAL;
	}

	list = drm_alloc(sizeof(*list), DRM_MEM_MAPS);
	if (!list) {
		drm_free(map, sizeof(*map), DRM_MEM_MAPS);
		return -EINVAL;
	}
	memset(list, 0, sizeof(*list));
	list->map = map;

	down(&dev->struct_sem);
	list_add(&list->head, &dev->maplist->head);
	/* Assign a 32-bit handle */
	/* We do it here so that dev->struct_sem protects the increment */
	list->user_token = HandleID(map->type == _DRM_SHM
				    ? (unsigned long)map->handle
				    : map->offset, dev);
	up(&dev->struct_sem);

	*maplist = list;
	return 0;
}

int drm_addmap(drm_device_t * dev, unsigned int offset,
	       unsigned int size, drm_map_type_t type,
	       drm_map_flags_t flags, drm_local_map_t ** map_ptr)
{
	drm_map_list_t *list;
	int rc;

	rc = drm_addmap_core(dev, offset, size, type, flags, &list);
	if (!rc)
		*map_ptr = list->map;
	return rc;
}

EXPORT_SYMBOL(drm_addmap);

int drm_addmap_ioctl(struct inode *inode, struct file *filp,
		     unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_map_t map;
	drm_map_list_t *maplist;
	drm_map_t __user *argp = (void __user *)arg;
	int err;

	if (!(filp->f_mode & 3))
		return -EACCES;	/* Require read/write */

	if (copy_from_user(&map, argp, sizeof(map))) {
		return -EFAULT;
	}

	err = drm_addmap_core(dev, map.offset, map.size, map.type, map.flags,
			      &maplist);

	if (err)
		return err;

	if (copy_to_user(argp, maplist->map, sizeof(drm_map_t)))
		return -EFAULT;

	/* avoid a warning on 64-bit, this casting isn't very nice, but the API is set so too late */
	if (put_user((void *)(unsigned long)maplist->user_token, &argp->handle))
		return -EFAULT;
	return 0;
}

/**
 * Remove a map private from list and deallocate resources if the mapping
 * isn't in use.
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg pointer to a drm_map_t structure.
 * \return zero on success or a negative value on error.
 *
 * Searches the map on drm_device::maplist, removes it from the list, see if
 * its being used, and free any associate resource (such as MTRR's) if it's not
 * being on use.
 *
 * \sa drm_addmap
 */
int drm_rmmap_locked(drm_device_t * dev, drm_local_map_t * map)
{
	struct list_head *list;
	drm_map_list_t *r_list = NULL;
	drm_dma_handle_t dmah;

	/* Find the list entry for the map and remove it */
	list_for_each(list, &dev->maplist->head) {
		r_list = list_entry(list, drm_map_list_t, head);

		if (r_list->map == map) {
			list_del(list);
			drm_free(list, sizeof(*list), DRM_MEM_MAPS);
			break;
		}
	}

	/* List has wrapped around to the head pointer, or it's empty and we
	 * didn't find anything.
	 */
	if (list == (&dev->maplist->head)) {
		return -EINVAL;
	}

	switch (map->type) {
	case _DRM_REGISTERS:
		drm_ioremapfree(map->handle, map->size, dev);
		/* FALLTHROUGH */
	case _DRM_FRAME_BUFFER:
		if (drm_core_has_MTRR(dev) && map->mtrr >= 0) {
			int retcode;
			retcode = mtrr_del(map->mtrr, map->offset, map->size);
			DRM_DEBUG("mtrr_del=%d\n", retcode);
		}
		break;
	case _DRM_SHM:
		vfree(map->handle);
		break;
	case _DRM_AGP:
	case _DRM_SCATTER_GATHER:
		break;
	case _DRM_CONSISTENT:
		dmah.vaddr = map->handle;
		dmah.busaddr = map->offset;
		dmah.size = map->size;
		__drm_pci_free(dev, &dmah);
		break;
	}
	drm_free(map, sizeof(*map), DRM_MEM_MAPS);

	return 0;
}

EXPORT_SYMBOL(drm_rmmap_locked);

int drm_rmmap(drm_device_t * dev, drm_local_map_t * map)
{
	int ret;

	down(&dev->struct_sem);
	ret = drm_rmmap_locked(dev, map);
	up(&dev->struct_sem);

	return ret;
}

EXPORT_SYMBOL(drm_rmmap);

/* The rmmap ioctl appears to be unnecessary.  All mappings are torn down on
 * the last close of the device, and this is necessary for cleanup when things
 * exit uncleanly.  Therefore, having userland manually remove mappings seems
 * like a pointless exercise since they're going away anyway.
 *
 * One use case might be after addmap is allowed for normal users for SHM and
 * gets used by drivers that the server doesn't need to care about.  This seems
 * unlikely.
 */
int drm_rmmap_ioctl(struct inode *inode, struct file *filp,
		    unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_map_t request;
	drm_local_map_t *map = NULL;
	struct list_head *list;
	int ret;

	if (copy_from_user(&request, (drm_map_t __user *) arg, sizeof(request))) {
		return -EFAULT;
	}

	down(&dev->struct_sem);
	list_for_each(list, &dev->maplist->head) {
		drm_map_list_t *r_list = list_entry(list, drm_map_list_t, head);

		if (r_list->map &&
		    r_list->user_token == (unsigned long)request.handle &&
		    r_list->map->flags & _DRM_REMOVABLE) {
			map = r_list->map;
			break;
		}
	}

	/* List has wrapped around to the head pointer, or its empty we didn't
	 * find anything.
	 */
	if (list == (&dev->maplist->head)) {
		up(&dev->struct_sem);
		return -EINVAL;
	}

	if (!map)
		return -EINVAL;

	/* Register and framebuffer maps are permanent */
	if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
		up(&dev->struct_sem);
		return 0;
	}

	ret = drm_rmmap_locked(dev, map);

	up(&dev->struct_sem);

	return ret;
}

/**
 * Cleanup after an error on one of the addbufs() functions.
 *
 * \param dev DRM device.
 * \param entry buffer entry where the error occurred.
 *
 * Frees any pages and buffers associated with the given entry.
 */
static void drm_cleanup_buf_error(drm_device_t * dev, drm_buf_entry_t * entry)
{
	int i;

	if (entry->seg_count) {
		for (i = 0; i < entry->seg_count; i++) {
			if (entry->seglist[i]) {
				drm_free_pages(entry->seglist[i],
					       entry->page_order, DRM_MEM_DMA);
			}
		}
		drm_free(entry->seglist,
			 entry->seg_count *
			 sizeof(*entry->seglist), DRM_MEM_SEGS);

		entry->seg_count = 0;
	}

	if (entry->buf_count) {
		for (i = 0; i < entry->buf_count; i++) {
			if (entry->buflist[i].dev_private) {
				drm_free(entry->buflist[i].dev_private,
					 entry->buflist[i].dev_priv_size,
					 DRM_MEM_BUFS);
			}
		}
		drm_free(entry->buflist,
			 entry->buf_count *
			 sizeof(*entry->buflist), DRM_MEM_BUFS);

		entry->buf_count = 0;
	}
}

#if __OS_HAS_AGP
/**
 * Add AGP buffers for DMA transfers.
 *
 * \param dev drm_device_t to which the buffers are to be added.
 * \param request pointer to a drm_buf_desc_t describing the request.
 * \return zero on success or a negative number on failure.
 *
 * After some sanity checks creates a drm_buf structure for each buffer and
 * reallocates the buffer list of the same size order to accommodate the new
 * buffers.
 */
int drm_addbufs_agp(drm_device_t * dev, drm_buf_desc_t * request)
{
	drm_device_dma_t *dma = dev->dma;
	drm_buf_entry_t *entry;
	drm_buf_t *buf;
	unsigned long offset;
	unsigned long agp_offset;
	int count;
	int order;
	int size;
	int alignment;
	int page_order;
	int total;