drm: fix issue with handle lookup for a 0 handle

On 32-bit PPC a 0 handle is valid for AGP space, the 32/64 lookup
doesn't handle 0 correctly.

From: Ben Herrenschmidt <benh@kernel.crashing.org> and Paul Mackerras <paulus@samba.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>
This commit is contained in:
Dave Airlie 2005-09-05 21:23:23 +10:00 committed by Dave Airlie
parent f505380ba7
commit 89625eb186

View file

@ -48,8 +48,8 @@ unsigned long drm_get_resource_len(drm_device_t *dev, unsigned int resource)
}
EXPORT_SYMBOL(drm_get_resource_len);
static drm_local_map_t *drm_find_matching_map(drm_device_t *dev,
drm_local_map_t *map)
static drm_map_list_t *drm_find_matching_map(drm_device_t *dev,
drm_local_map_t *map)
{
struct list_head *list;
@ -57,7 +57,7 @@ static drm_local_map_t *drm_find_matching_map(drm_device_t *dev,
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->map;
return entry;
}
}
@ -114,14 +114,13 @@ static __inline__ unsigned int HandleID(unsigned long lhandle, drm_device_t *dev
* type. Adds the map to the map list drm_device::maplist. Adds MTRR's where
* applicable and if supported by the kernel.
*/
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)
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;
drm_local_map_t *found_map;
map = drm_alloc( sizeof(*map), DRM_MEM_MAPS );
if ( !map )
@ -166,17 +165,17 @@ int drm_addmap(drm_device_t * dev, unsigned int offset,
* needing to be aware of it. Therefore, we just return success
* when the server tries to create a duplicate map.
*/
found_map = drm_find_matching_map(dev, map);
if (found_map != NULL) {
if (found_map->size != map->size) {
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, found_map->size);
found_map->size = map->size;
map->type, map->size, list->map->size);
list->map->size = map->size;
}
drm_free(map, sizeof(*map), DRM_MEM_MAPS);
*map_ptr = found_map;
*maplist = list;
return 0;
}
@ -264,9 +263,22 @@ int drm_addmap(drm_device_t * dev, unsigned int offset,
: map->offset, dev);
up(&dev->struct_sem);
*map_ptr = map;
*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,
@ -275,10 +287,9 @@ int drm_addmap_ioctl(struct inode *inode, struct file *filp,
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->head->dev;
drm_map_t map;
drm_map_t *map_ptr;
drm_map_list_t *maplist;
drm_map_t __user *argp = (void __user *)arg;
int err;
unsigned long handle = 0;
if (!(filp->f_mode & 3))
return -EACCES; /* Require read/write */
@ -287,26 +298,15 @@ int drm_addmap_ioctl(struct inode *inode, struct file *filp,
return -EFAULT;
}
err = drm_addmap(dev, map.offset, map.size, map.type, map.flags,
&map_ptr);
err = drm_addmap_core(dev, map.offset, map.size, map.type, map.flags,
&maplist);
if (err) {
if (err)
return err;
}
{
drm_map_list_t *_entry;
list_for_each_entry(_entry, &dev->maplist->head, head) {
if (_entry->map == map_ptr)
handle = _entry->user_token;
}
if (!handle)
return -EFAULT;
}
if (copy_to_user(argp, map_ptr, sizeof(*map_ptr)))
if (copy_to_user(argp, maplist->map, sizeof(drm_map_t)))
return -EFAULT;
if (put_user(handle, &argp->handle))
if (put_user(maplist->user_token, &argp->handle))
return -EFAULT;
return 0;
}