sys/dev/drm/drm_fops.c

   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  * $DragonFly: src/sys/dev/drm/drm_fops.c,v 1.1 2008/04/05 18:12:29 hasso Exp $
  31  */
  32
  33 /** @file drm_fops.c
  34  * Support code for dealing with the file privates associated with each
  35  * open of the DRM device.
  36  */
  37
  38 #include "drmP.h"
  39
  40 drm_file_t *drm_find_file_by_proc(drm_device_t *dev, DRM_STRUCTPROC *p)
  41 {
  42 #if __FreeBSD_version >= 500021
  43         uid_t uid = p->td_ucred->cr_svuid;
  44         pid_t pid = p->td_proc->p_pid;
  45 #elif defined(__DragonFly__)
  46         uid_t uid = p->td_proc->p_ucred->cr_svuid;
  47         pid_t pid = p->td_proc->p_pid;
  48 #else
  49         uid_t uid = p->p_cred->p_svuid;
  50         pid_t pid = p->p_pid;
  51 #endif
  52         drm_file_t *priv;
  53
  54         DRM_SPINLOCK_ASSERT(&dev->dev_lock);
  55
  56         TAILQ_FOREACH(priv, &dev->files, link)
  57                 if (priv->pid == pid && priv->uid == uid)
  58                         return priv;
  59         return NULL;
  60 }
  61
  62 /* drm_open_helper is called whenever a process opens /dev/drm. */
  63 int drm_open_helper(struct cdev *kdev, int flags, int fmt, DRM_STRUCTPROC *p,
  64                     drm_device_t *dev)
  65 {
  66         int          m = minor(kdev);
  67         drm_file_t   *priv;
  68         int retcode;
  69
  70         if (flags & O_EXCL)
  71                 return EBUSY; /* No exclusive opens */
  72         dev->flags = flags;
  73
  74         DRM_DEBUG("pid = %d, minor = %d\n", DRM_CURRENTPID, m);
  75
  76         DRM_LOCK();
  77         priv = drm_find_file_by_proc(dev, p);
  78         if (priv) {
  79                 priv->refs++;
  80         } else {
  81                 priv = malloc(sizeof(*priv), M_DRM, M_NOWAIT | M_ZERO);
  82                 if (priv == NULL) {
  83                         DRM_UNLOCK();
  84                         return ENOMEM;
  85                 }
  86 #if __FreeBSD_version >= 500000
  87                 priv->uid               = p->td_ucred->cr_svuid;
  88                 priv->pid               = p->td_proc->p_pid;
  89 #elif defined(__DragonFly__)
  90                 priv->uid               = p->td_proc->p_ucred->cr_svuid;
  91                 priv->pid               = p->td_proc->p_pid;
  92 #else
  93                 priv->uid               = p->p_cred->p_svuid;
  94                 priv->pid               = p->p_pid;
  95 #endif
  96
  97                 priv->refs              = 1;
  98                 priv->minor             = m;
  99                 priv->ioctl_count       = 0;
 100
 101                 /* for compatibility root is always authenticated */
 102                 priv->authenticated     = DRM_SUSER(p);
 103
 104                 if (dev->driver.open) {
 105                         /* shared code returns -errno */
 106                         retcode = -dev->driver.open(dev, priv);
 107                         if (retcode != 0) {
 108                                 free(priv, M_DRM);
 109                                 DRM_UNLOCK();
 110                                 return retcode;
 111                         }
 112                 }
 113
 114                 /* first opener automatically becomes master */
 115                 priv->master = TAILQ_EMPTY(&dev->files);
 116
 117                 TAILQ_INSERT_TAIL(&dev->files, priv, link);
 118         }
 119         DRM_UNLOCK();
 120 #if defined(__FreeBSD__) || defined(__DragonFly__)
 121         kdev->si_drv1 = dev;
 122 #endif
 123         return 0;
 124 }
 125
 126
 127 /* The drm_read and drm_poll are stubs to prevent spurious errors
 128  * on older X Servers (4.3.0 and earlier) */
 129
 130 #ifdef __DragonFly__
 131 int drm_read(struct dev_read_args *ap)
 132 {
 133         return (0);
 134 }
 135
 136 int drm_poll(struct dev_poll_args *ap)
 137 {
 138         return (0);
 139 }
 140 #else
 141 int drm_read(struct cdev *kdev, struct uio *uio, int ioflag)
 142 {
 143         return 0;
 144 }
 145
 146 int drm_poll(struct cdev *kdev, int events, DRM_STRUCTPROC *p)
 147 {
 148         return 0;
 149 }
 150 #endif