xref: /dragonfly/sys/dev/drm/drm_global.c (revision 82730a9c)
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27 /*
28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29  * $FreeBSD: head/sys/dev/drm2/drm_global.c 248060 2013-03-08 18:11:02Z dumbbell $
30  */
31 
32 #include <drm/drmP.h>
33 #include <drm/drm_global.h>
34 
35 MALLOC_DEFINE(M_DRM_GLOBAL, "drm_global", "DRM Global Items");
36 
37 struct drm_global_item {
38 	struct lock mutex;
39 	void *object;
40 	int refcount;
41 };
42 
43 static struct drm_global_item glob[DRM_GLOBAL_NUM];
44 
45 void drm_global_init(void)
46 {
47 	int i;
48 
49 	for (i = 0; i < DRM_GLOBAL_NUM; ++i) {
50 		struct drm_global_item *item = &glob[i];
51 		lockinit(&item->mutex, "drmgi", 0, LK_CANRECURSE);
52 		item->object = NULL;
53 		item->refcount = 0;
54 	}
55 }
56 
57 void drm_global_release(void)
58 {
59 	int i;
60 	for (i = 0; i < DRM_GLOBAL_NUM; ++i) {
61 		struct drm_global_item *item = &glob[i];
62 		KKASSERT(item->object == NULL);
63 		KKASSERT(item->refcount == 0);
64 		lockuninit(&item->mutex);
65 	}
66 }
67 
68 int drm_global_item_ref(struct drm_global_reference *ref)
69 {
70 	int ret;
71 	struct drm_global_item *item = &glob[ref->global_type];
72 	void *object;
73 
74 	lockmgr(&item->mutex, LK_EXCLUSIVE);
75 	if (item->refcount == 0) {
76 		item->object = kmalloc(ref->size, M_DRM_GLOBAL,
77 		    M_WAITOK | M_ZERO);
78 
79 		ref->object = item->object;
80 		ret = ref->init(ref);
81 		if (unlikely(ret != 0))
82 			goto out_err;
83 
84 	}
85 	++item->refcount;
86 	ref->object = item->object;
87 	object = item->object;
88 	lockmgr(&item->mutex, LK_RELEASE);
89 	return 0;
90 out_err:
91 	lockmgr(&item->mutex, LK_RELEASE);
92 	item->object = NULL;
93 	return ret;
94 }
95 
96 void drm_global_item_unref(struct drm_global_reference *ref)
97 {
98 	struct drm_global_item *item = &glob[ref->global_type];
99 
100 	lockmgr(&item->mutex, LK_EXCLUSIVE);
101 	KKASSERT(item->refcount != 0);
102 	KKASSERT(ref->object == item->object);
103 	if (--item->refcount == 0) {
104 		ref->release(ref);
105 		drm_free(item->object, M_DRM_GLOBAL);
106 		item->object = NULL;
107 	}
108 	lockmgr(&item->mutex, LK_RELEASE);
109 }
110