path: root/include/drm
diff options
authorThomas Hellstrom <thellstrom@vmware.com>2013-12-18 14:13:29 +0100
committerThomas Hellstrom <thellstrom@vmware.com>2014-01-08 10:11:57 +0100
commit05efb1abecce6e36457ae1a7be29ded7ac52292a (patch)
tree59be0d416b8811b273bc1b64f34fa4f0f4cb7b04 /include/drm
parent859ae233cd0ee76b6143f948ba1cb6b0b4c342f8 (diff)
drm/ttm: ttm object security fixes for render nodes
When a client looks up a ttm object, don't look it up through the device hash table, but rather from the file hash table. That makes sure that the client has indeed put a reference on the object, or in gem terms, has opened the object; either using prime or using the global "name". To avoid a performance loss, make sure the file hash table entries can be looked up from under an RCU lock, and as a consequence, replace the rwlock with a spinlock, since we never need to take it in read mode only anymore. Finally add a ttm object lookup function for the device hash table, that is intended to be used when we put a ref object on a base object or, in gem terms, when we open the object. Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Brian Paul <brianp@vmware.com>
Diffstat (limited to 'include/drm')
1 files changed, 16 insertions, 2 deletions
diff --git a/include/drm/ttm/ttm_object.h b/include/drm/ttm/ttm_object.h
index 58b029894eb3..0097cc03034e 100644
--- a/include/drm/ttm/ttm_object.h
+++ b/include/drm/ttm/ttm_object.h
@@ -190,14 +190,26 @@ extern int ttm_base_object_init(struct ttm_object_file *tfile,
* @key: Hash key
* Looks up a struct ttm_base_object with the key @key.
- * Also verifies that the object is visible to the application, by
- * comparing the @tfile argument and checking the object shareable flag.
extern struct ttm_base_object *ttm_base_object_lookup(struct ttm_object_file
*tfile, uint32_t key);
+ * ttm_base_object_lookup_for_ref
+ *
+ * @tdev: Pointer to a struct ttm_object_device.
+ * @key: Hash key
+ *
+ * Looks up a struct ttm_base_object with the key @key.
+ * This function should only be used when the struct tfile associated with the
+ * caller doesn't yet have a reference to the base object.
+ */
+extern struct ttm_base_object *
+ttm_base_object_lookup_for_ref(struct ttm_object_device *tdev, uint32_t key);
* ttm_base_object_unref
* @p_base: Pointer to a pointer referencing a struct ttm_base_object.
@@ -218,6 +230,8 @@ extern void ttm_base_object_unref(struct ttm_base_object **p_base);
* @existed: Upon completion, indicates that an identical reference object
* already existed, and the refcount was upped on that object instead.
+ * Checks that the base object is shareable and adds a ref object to it.
+ *
* Adding a ref object to a base object is basically like referencing the
* base object, but a user-space application holds the reference. When the
* file corresponding to @tfile is closed, all its reference objects are