xref: /freebsd/sys/dev/drm2/drm_vm.c (revision 2a664c03e55254b0f3b32dcdfc78179c0a57a8d2)
1 /*-
2  * Copyright 2003 Eric Anholt
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * ERIC ANHOLT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
20  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <sys/cdefs.h>
25 __FBSDID("$FreeBSD$");
26 
27 /** @file drm_vm.c
28  * Support code for mmaping of DRM maps.
29  */
30 
31 #include <dev/drm2/drmP.h>
32 #include <dev/drm2/drm.h>
33 
34 int
35 drm_mmap(struct cdev *kdev, vm_ooffset_t offset, vm_paddr_t *paddr,
36     int prot, vm_memattr_t *memattr)
37 {
38 	struct drm_device *dev = drm_get_device_from_kdev(kdev);
39 	struct drm_file *file_priv = NULL;
40 	drm_local_map_t *map;
41 	enum drm_map_type type;
42 	vm_paddr_t phys;
43 	int error;
44 
45 	/* d_mmap gets called twice, we can only reference file_priv during
46 	 * the first call.  We need to assume that if error is EBADF the
47 	 * call was succesful and the client is authenticated.
48 	 */
49 	error = devfs_get_cdevpriv((void **)&file_priv);
50 	if (error == ENOENT) {
51 		DRM_ERROR("Could not find authenticator!\n");
52 		return EINVAL;
53 	}
54 
55 	if (file_priv && !file_priv->authenticated)
56 		return EACCES;
57 
58 	DRM_DEBUG("called with offset %016jx\n", offset);
59 	if (dev->dma && offset < ptoa(dev->dma->page_count)) {
60 		drm_device_dma_t *dma = dev->dma;
61 
62 		DRM_SPINLOCK(&dev->dma_lock);
63 
64 		if (dma->pagelist != NULL) {
65 			unsigned long page = offset >> PAGE_SHIFT;
66 			unsigned long phys = dma->pagelist[page];
67 
68 			DRM_SPINUNLOCK(&dev->dma_lock);
69 			*paddr = phys;
70 			return 0;
71 		} else {
72 			DRM_SPINUNLOCK(&dev->dma_lock);
73 			return -1;
74 		}
75 	}
76 
77 	/* A sequential search of a linked list is
78 	   fine here because: 1) there will only be
79 	   about 5-10 entries in the list and, 2) a
80 	   DRI client only has to do this mapping
81 	   once, so it doesn't have to be optimized
82 	   for performance, even if the list was a
83 	   bit longer.
84 	*/
85 	DRM_LOCK(dev);
86 	TAILQ_FOREACH(map, &dev->maplist, link) {
87 		if (offset >> DRM_MAP_HANDLE_SHIFT ==
88 		    (unsigned long)map->handle >> DRM_MAP_HANDLE_SHIFT)
89 			break;
90 	}
91 
92 	if (map == NULL) {
93 		DRM_DEBUG("Can't find map, request offset = %016jx\n", offset);
94 		TAILQ_FOREACH(map, &dev->maplist, link) {
95 			DRM_DEBUG("map offset = %016lx, handle = %016lx\n",
96 			    map->offset, (unsigned long)map->handle);
97 		}
98 		DRM_UNLOCK(dev);
99 		return -1;
100 	}
101 	if (((map->flags & _DRM_RESTRICTED) && !DRM_SUSER(DRM_CURPROC))) {
102 		DRM_UNLOCK(dev);
103 		DRM_DEBUG("restricted map\n");
104 		return -1;
105 	}
106 	type = map->type;
107 	DRM_UNLOCK(dev);
108 
109 	offset = offset & ((1ULL << DRM_MAP_HANDLE_SHIFT) - 1);
110 
111 	switch (type) {
112 	case _DRM_FRAME_BUFFER:
113 	case _DRM_AGP:
114 		*memattr = VM_MEMATTR_WRITE_COMBINING;
115 		/* FALLTHROUGH */
116 	case _DRM_REGISTERS:
117 		phys = map->offset + offset;
118 		break;
119 	case _DRM_SCATTER_GATHER:
120 		*memattr = VM_MEMATTR_WRITE_COMBINING;
121 		/* FALLTHROUGH */
122 	case _DRM_CONSISTENT:
123 	case _DRM_SHM:
124 		phys = vtophys((char *)map->virtual + offset);
125 		break;
126 	default:
127 		DRM_ERROR("bad map type %d\n", type);
128 		return -1;	/* This should never happen. */
129 	}
130 
131 	*paddr = phys;
132 	return 0;
133 }
134 
135