drm_vm.c revision 189914 
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: head/sys/dev/drm/drm_vm.c 189914 2009-03-17 03:50:35Z rnoland $");
26
27/** @file drm_vm.c
28 * Support code for mmaping of DRM maps.
29 */
30
31#include "dev/drm/drmP.h"
32#include "dev/drm/drm.h"
33
34int drm_mmap(struct cdev *kdev, vm_offset_t offset, vm_paddr_t *paddr,
35    int prot)
36{
37	struct drm_device *dev = drm_get_device_from_kdev(kdev);
38	struct drm_file *file_priv = NULL;
39	drm_local_map_t *map;
40	enum drm_map_type type;
41	vm_paddr_t phys;
42	int error;
43
44	/* d_mmap gets called twice, we can only reference file_priv during
45	 * the first call.  We need to assume that if error is EBADF the
46	 * call was succesful and the client is authenticated.
47	 */
48	error = devfs_get_cdevpriv((void **)&file_priv);
49	if (error == ENOENT) {
50		DRM_ERROR("Could not find authenticator!\n");
51		return EINVAL;
52	}
53
54	if (file_priv && !file_priv->authenticated)
55		return EACCES;
56
57	if (dev->dma && offset >= 0 && offset < ptoa(dev->dma->page_count)) {
58		drm_device_dma_t *dma = dev->dma;
59
60		DRM_SPINLOCK(&dev->dma_lock);
61
62		if (dma->pagelist != NULL) {
63			unsigned long page = offset >> PAGE_SHIFT;
64			unsigned long phys = dma->pagelist[page];
65
66			DRM_SPINUNLOCK(&dev->dma_lock);
67			*paddr = phys;
68			return 0;
69		} else {
70			DRM_SPINUNLOCK(&dev->dma_lock);
71			return -1;
72		}
73	}
74
75				/* A sequential search of a linked list is
76				   fine here because: 1) there will only be
77				   about 5-10 entries in the list and, 2) a
78				   DRI client only has to do this mapping
79				   once, so it doesn't have to be optimized
80				   for performance, even if the list was a
81				   bit longer. */
82	DRM_LOCK();
83	TAILQ_FOREACH(map, &dev->maplist, link) {
84		if (offset >= map->offset && offset < map->offset + map->size)
85			break;
86	}
87
88	if (map == NULL) {
89		DRM_DEBUG("Can't find map, requested offset = %016lx\n",
90		    offset);
91		TAILQ_FOREACH(map, &dev->maplist, link) {
92			DRM_DEBUG("map offset = %016lx, handle = %016lx\n",
93			map->offset, (unsigned long)map->handle);
94		}
95		DRM_UNLOCK();
96		return -1;
97	}
98	if (((map->flags&_DRM_RESTRICTED) && !DRM_SUSER(DRM_CURPROC))) {
99		DRM_UNLOCK();
100		DRM_DEBUG("restricted map\n");
101		return -1;
102	}
103	type = map->type;
104	DRM_UNLOCK();
105
106	switch (type) {
107	case _DRM_FRAME_BUFFER:
108	case _DRM_REGISTERS:
109	case _DRM_AGP:
110		phys = offset;
111		break;
112	case _DRM_CONSISTENT:
113		phys = vtophys((char *)map->handle + (offset - map->offset));
114		break;
115	case _DRM_SCATTER_GATHER:
116	case _DRM_SHM:
117		phys = vtophys(offset);
118		break;
119	default:
120		DRM_ERROR("bad map type %d\n", type);
121		return -1;	/* This should never happen. */
122	}
123
124	*paddr = phys;
125	return 0;
126}
127
128