xref: /netbsd-src/sys/external/bsd/drm/dist/bsd-core/drm_fops.c (revision 992e698d04e434422481fbeacd69495ffe24da60)
1 /*-
2  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
3  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23  * OTHER DEALINGS IN THE SOFTWARE.
24  *
25  * Authors:
26  *    Rickard E. (Rik) Faith <faith@valinux.com>
27  *    Daryll Strauss <daryll@valinux.com>
28  *    Gareth Hughes <gareth@valinux.com>
29  *
30  */
31 
32 /** @file drm_fops.c
33  * Support code for dealing with the file privates associated with each
34  * open of the DRM device.
35  */
36 
37 #include "drmP.h"
38 
39 #if defined(__NetBSD__)
40 struct drm_file *
drm_find_file_by_proc(struct drm_device * dev,struct proc * p)41 drm_find_file_by_proc(struct drm_device *dev, struct proc *p)
42 {
43 	uid_t uid = kauth_cred_getsvuid(p->p_cred);
44 	pid_t pid = p->p_pid;
45 	struct drm_file *priv;
46 
47 	DRM_SPINLOCK_ASSERT(&dev->dev_lock);
48 
49 	TAILQ_FOREACH(priv, &dev->files, link) {
50 		if (priv->pid == pid && priv->uid == uid)
51 			return priv;
52 	}
53 
54 	return NULL;
55 }
56 
57 /* drm_open_helper is called whenever a process opens /dev/drm. */
drm_open_helper(dev_t kdev,int flags,int fmt,struct proc * p,struct drm_device * dev)58 int drm_open_helper(dev_t kdev, int flags, int fmt, struct proc *p,
59 		    struct drm_device *dev)
60 {
61 	int	     m = minor(kdev);
62 	struct drm_file   *priv;
63 	int retcode;
64 
65 	if (flags & O_EXCL)
66 		return EBUSY; /* No exclusive opens */
67 	dev->flags = flags;
68 
69 	DRM_DEBUG("pid = %d, minor = %d\n", DRM_CURRENTPID, m);
70 
71 	DRM_LOCK();
72 	priv = drm_find_file_by_proc(dev, p);
73 	if (!priv) {
74 		priv = malloc(sizeof(*priv), DRM_MEM_FILES, M_NOWAIT | M_ZERO);
75 		if (priv == NULL) {
76 			DRM_UNLOCK();
77 			return ENOMEM;
78 		}
79 		priv->uid		= kauth_cred_getsvuid(p->p_cred);
80 		priv->pid		= p->p_pid;
81 
82 		priv->minor		= m;
83 		priv->ioctl_count 	= 0;
84 
85 		/* for compatibility root is always authenticated */
86 		priv->authenticated	= DRM_SUSER(p);
87 
88 		if (dev->driver->open) {
89 			/* shared code returns -errno */
90 			retcode = -dev->driver->open(dev, priv);
91 			if (retcode != 0) {
92 				free(priv, DRM_MEM_FILES);
93 				DRM_UNLOCK();
94 				return retcode;
95 			}
96 		}
97 
98 		/* first opener automatically becomes master */
99 		priv->master = TAILQ_EMPTY(&dev->files);
100 
101 		TAILQ_INSERT_TAIL(&dev->files, priv, link);
102 	}
103 	DRM_UNLOCK();
104 
105 	return 0;
106 }
107 
108 #elif   defined(__FreeBSD__)
109 
110 /* drm_open_helper is called whenever a process opens /dev/drm. */
drm_open_helper(struct cdev * kdev,int flags,int fmt,DRM_STRUCTPROC * p,struct drm_device * dev)111 int drm_open_helper(struct cdev *kdev, int flags, int fmt, DRM_STRUCTPROC *p,
112 		    struct drm_device *dev)
113 {
114 	struct drm_file *priv;
115 	int m = minor(kdev);
116 	int retcode;
117 
118 	if (flags & O_EXCL)
119 		return EBUSY; /* No exclusive opens */
120 	dev->flags = flags;
121 
122 	DRM_DEBUG("pid = %d, minor = %d\n", DRM_CURRENTPID, m);
123 
124 	priv = malloc(sizeof(*priv), DRM_MEM_FILES, M_NOWAIT | M_ZERO);
125 	if (priv == NULL) {
126 		return ENOMEM;
127 	}
128 
129 	retcode = devfs_set_cdevpriv(priv, drm_close);
130 	if (retcode != 0) {
131 		free(priv, DRM_MEM_FILES);
132 		return retcode;
133 	}
134 
135 	DRM_LOCK();
136 	priv->dev		= dev;
137 	priv->uid		= p->td_ucred->cr_svuid;
138 	priv->pid		= p->td_proc->p_pid;
139 	priv->minor		= m;
140 	priv->ioctl_count 	= 0;
141 
142 	/* for compatibility root is always authenticated */
143 	priv->authenticated	= DRM_SUSER(p);
144 
145 	if (dev->driver->open) {
146 		/* shared code returns -errno */
147 		retcode = -dev->driver->open(dev, priv);
148 		if (retcode != 0) {
149 			devfs_clear_cdevpriv();
150 			free(priv, DRM_MEM_FILES);
151 			DRM_UNLOCK();
152 			return retcode;
153 		}
154 	}
155 
156 	/* first opener automatically becomes master */
157 	priv->master = TAILQ_EMPTY(&dev->files);
158 
159 	TAILQ_INSERT_TAIL(&dev->files, priv, link);
160 	DRM_UNLOCK();
161 	kdev->si_drv1 = dev;
162 	return 0;
163 }
164 #endif
165 
166 /* The drm_read and drm_poll are stubs to prevent spurious errors
167  * on older X Servers (4.3.0 and earlier) */
168 
drm_read(DRM_CDEV kdev,struct uio * uio,int ioflag)169 int drm_read(DRM_CDEV kdev, struct uio *uio, int ioflag)
170 {
171 	return 0;
172 }
173 
drm_poll(DRM_CDEV kdev,int events,DRM_STRUCTCDEVPROC * p)174 int drm_poll(DRM_CDEV kdev, int events, DRM_STRUCTCDEVPROC *p)
175 {
176 	return 0;
177 }
178