xref: /titanic_41/usr/src/uts/common/io/drm/drm_fops.c (revision d2b5b2d357ee3172eacb6860be1891259902203d)
1 /*
2  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /* BEGIN CSTYLED */
7 
8 /* drm_fops.h -- File operations for DRM -*- linux-c -*-
9  * Created: Mon Jan  4 08:58:31 1999 by faith@valinux.com
10  */
11 /*-
12  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
13  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14  * Copyright (c) 2009, Intel Corporation.
15  * All Rights Reserved.
16  *
17  * Permission is hereby granted, free of charge, to any person obtaining a
18  * copy of this software and associated documentation files (the "Software"),
19  * to deal in the Software without restriction, including without limitation
20  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
21  * and/or sell copies of the Software, and to permit persons to whom the
22  * Software is furnished to do so, subject to the following conditions:
23  *
24  * The above copyright notice and this permission notice (including the next
25  * paragraph) shall be included in all copies or substantial portions of the
26  * Software.
27  *
28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
29  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
30  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
31  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
32  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
33  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
34  * OTHER DEALINGS IN THE SOFTWARE.
35  *
36  * Authors:
37  *    Rickard E. (Rik) Faith <faith@valinux.com>
38  *    Daryll Strauss <daryll@valinux.com>
39  *    Gareth Hughes <gareth@valinux.com>
40  *
41  */
42 
43 /* END CSTYLED */
44 
45 #include "drmP.h"
46 
47 /*ARGSUSED*/
48 drm_file_t *
49 drm_find_file_by_proc(drm_device_t *dev, cred_t *credp)
50 {
51 	pid_t pid = ddi_get_pid();
52 	drm_file_t *priv;
53 
54 	TAILQ_FOREACH(priv, &dev->files, link)
55 	if (priv->pid == pid)
56 		return (priv);
57 	return (NULL);
58 }
59 
60 
61 drm_cminor_t *
62 drm_find_file_by_minor(drm_device_t *dev, int minor)
63 {
64 	drm_cminor_t	*mp;
65 
66 	TAILQ_FOREACH(mp, &dev->minordevs, link) {
67 		if (mp->minor == minor)
68 			return (mp);
69 	}
70 	return (NULL);
71 }
72 
73 /* drm_open_helper is called whenever a process opens /dev/drm. */
74 /*ARGSUSED*/
75 int
76 drm_open_helper(drm_device_t *dev, drm_cminor_t *mp, int flags,
77     int otyp, cred_t *credp)
78 {
79 	drm_file_t   *priv;
80 	pid_t pid;
81 	int retcode;
82 
83 	if (flags & FEXCL)
84 		return (EBUSY); /* No exclusive opens */
85 	dev->flags = flags;
86 
87 	pid = ddi_get_pid();
88 	DRM_DEBUG("drm_open_helper :pid = %d", pid);
89 
90 	DRM_LOCK();
91 	priv = drm_find_file_by_proc(dev, credp);
92 	if (priv) {
93 		priv->refs++;
94 	} else {
95 		priv = drm_alloc(sizeof (*priv), DRM_MEM_FILES);
96 		if (priv == NULL) {
97 			DRM_UNLOCK();
98 			return (ENOMEM);
99 		}
100 		bzero(priv, sizeof (*priv));
101 
102 		priv->uid		= crgetsuid(credp);
103 		priv->pid		= pid;
104 
105 		priv->refs		= 1;
106 		priv->minor		= 5;	/* just for hack */
107 		priv->ioctl_count 	= 0;
108 
109 		/* for compatibility root is always authenticated */
110 		priv->authenticated	= DRM_SUSER(credp);
111 
112 		if (dev->driver->use_gem == 1)
113 			drm_gem_open(priv);
114 
115 		if (dev->driver->open) {
116 			retcode = dev->driver->open(dev, priv);
117 			if (retcode != 0) {
118 				drm_free(priv, sizeof (*priv), DRM_MEM_FILES);
119 				DRM_UNLOCK();
120 				return (retcode);
121 			}
122 		}
123 
124 		/* first opener automatically becomes master */
125 		priv->master = TAILQ_EMPTY(&dev->files);
126 		TAILQ_INSERT_TAIL(&dev->files, priv, link);
127 	}
128 	mp->fpriv = priv;
129 	DRM_UNLOCK();
130 	return (0);
131 }
132