diff options
| -rw-r--r-- | drivers/gpu/drm/drm_fops.c | 50 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_stub.c | 39 | ||||
| -rw-r--r-- | include/drm/drmP.h | 4 |
3 files changed, 70 insertions, 23 deletions
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index 6466cb5d8b1f..79478191404a 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -79,23 +79,22 @@ static int drm_setup(struct drm_device * dev) */ int drm_open(struct inode *inode, struct file *filp) { - struct drm_device *dev = NULL; - int minor_id = iminor(inode); + struct drm_device *dev; struct drm_minor *minor; - int retcode = 0; + int retcode; int need_setup = 0; struct address_space *old_mapping; struct address_space *old_imapping; - minor = idr_find(&drm_minors_idr, minor_id); - if (!minor) - return -ENODEV; - - if (!(dev = minor->dev)) - return -ENODEV; + minor = drm_minor_acquire(iminor(inode)); + if (IS_ERR(minor)) + return PTR_ERR(minor); - if (drm_device_is_unplugged(dev)) - return -ENODEV; + dev = minor->dev; + if (drm_device_is_unplugged(dev)) { + retcode = -ENODEV; + goto err_release; + } if (!dev->open_count++) need_setup = 1; @@ -128,6 +127,8 @@ err_undo: dev->dev_mapping = old_mapping; mutex_unlock(&dev->struct_mutex); dev->open_count--; +err_release: + drm_minor_release(minor); return retcode; } EXPORT_SYMBOL(drm_open); @@ -143,33 +144,33 @@ EXPORT_SYMBOL(drm_open); */ int drm_stub_open(struct inode *inode, struct file *filp) { - struct drm_device *dev = NULL; + struct drm_device *dev; struct drm_minor *minor; - int minor_id = iminor(inode); int err = -ENODEV; const struct file_operations *new_fops; DRM_DEBUG("\n"); mutex_lock(&drm_global_mutex); - minor = idr_find(&drm_minors_idr, minor_id); - if (!minor) - goto out; - - if (!(dev = minor->dev)) - goto out; + minor = drm_minor_acquire(iminor(inode)); + if (IS_ERR(minor)) + goto out_unlock; + dev = minor->dev; if (drm_device_is_unplugged(dev)) - goto out; + goto out_release; new_fops = fops_get(dev->driver->fops); if (!new_fops) - goto out; + goto out_release; replace_fops(filp, new_fops); if (filp->f_op->open) err = filp->f_op->open(inode, filp); -out: + +out_release: + drm_minor_release(minor); +out_unlock: mutex_unlock(&drm_global_mutex); return err; } @@ -453,7 +454,8 @@ int drm_lastclose(struct drm_device * dev) int drm_release(struct inode *inode, struct file *filp) { struct drm_file *file_priv = filp->private_data; - struct drm_device *dev = file_priv->minor->dev; + struct drm_minor *minor = file_priv->minor; + struct drm_device *dev = minor->dev; int retcode = 0; mutex_lock(&drm_global_mutex); @@ -575,6 +577,8 @@ int drm_release(struct inode *inode, struct file *filp) } mutex_unlock(&drm_global_mutex); + drm_minor_release(minor); + return retcode; } EXPORT_SYMBOL(drm_release); diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c index f2f0249304b7..269048215e82 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -356,6 +356,45 @@ static void drm_unplug_minor(struct drm_minor *minor) } /** + * drm_minor_acquire - Acquire a DRM minor + * @minor_id: Minor ID of the DRM-minor + * + * Looks up the given minor-ID and returns the respective DRM-minor object. The + * refence-count of the underlying device is increased so you must release this + * object with drm_minor_release(). + * + * As long as you hold this minor, it is guaranteed that the object and the + * minor->dev pointer will stay valid! However, the device may get unplugged and + * unregistered while you hold the minor. + * + * Returns: + * Pointer to minor-object with increased device-refcount, or PTR_ERR on + * failure. + */ +struct drm_minor *drm_minor_acquire(unsigned int minor_id) +{ + struct drm_minor *minor; + + minor = idr_find(&drm_minors_idr, minor_id); + if (!minor) + return ERR_PTR(-ENODEV); + + drm_dev_ref(minor->dev); + return minor; +} + +/** + * drm_minor_release - Release DRM minor + * @minor: Pointer to DRM minor object + * + * Release a minor that was previously acquired via drm_minor_acquire(). + */ +void drm_minor_release(struct drm_minor *minor) +{ + drm_dev_unref(minor->dev); +} + +/** * drm_put_minor - Destroy DRM minor * @minor: Minor to destroy * diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 4e53f1607355..82963167f161 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1672,6 +1672,10 @@ void drm_dev_ref(struct drm_device *dev); void drm_dev_unref(struct drm_device *dev); int drm_dev_register(struct drm_device *dev, unsigned long flags); void drm_dev_unregister(struct drm_device *dev); + +struct drm_minor *drm_minor_acquire(unsigned int minor_id); +void drm_minor_release(struct drm_minor *minor); + /*@}*/ /* PCI section */ |
