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>
diff --git a/drivers/char/drm/drm_bufs.c b/drivers/char/drm/drm_bufs.c
index e0743eb..8eff073 100644
--- a/drivers/char/drm/drm_bufs.c
+++ b/drivers/char/drm/drm_bufs.c
@@ -48,8 +48,8 @@
}
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 @@
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 @@
* 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 @@
* 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 @@
: 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 @@
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 @@
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;
}