diff options
Diffstat (limited to 'drivers/gpu/drm/drm_fops.c')
| -rw-r--r-- | drivers/gpu/drm/drm_fops.c | 44 |
1 files changed, 30 insertions, 14 deletions
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index 7ef1b673e1be..133b4132983e 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -121,6 +121,8 @@ int drm_open(struct inode *inode, struct file *filp) int minor_id = iminor(inode); struct drm_minor *minor; int retcode = 0; + int need_setup = 0; + struct address_space *old_mapping; minor = idr_find(&drm_minors_idr, minor_id); if (!minor) @@ -132,23 +134,37 @@ int drm_open(struct inode *inode, struct file *filp) if (drm_device_is_unplugged(dev)) return -ENODEV; + if (!dev->open_count++) + need_setup = 1; + mutex_lock(&dev->struct_mutex); + old_mapping = dev->dev_mapping; + if (old_mapping == NULL) + dev->dev_mapping = &inode->i_data; + /* ihold ensures nobody can remove inode with our i_data */ + ihold(container_of(dev->dev_mapping, struct inode, i_data)); + inode->i_mapping = dev->dev_mapping; + filp->f_mapping = dev->dev_mapping; + mutex_unlock(&dev->struct_mutex); + retcode = drm_open_helper(inode, filp, dev); - if (!retcode) { - atomic_inc(&dev->counts[_DRM_STAT_OPENS]); - if (!dev->open_count++) - retcode = drm_setup(dev); - } - if (!retcode) { - mutex_lock(&dev->struct_mutex); - if (dev->dev_mapping == NULL) - dev->dev_mapping = &inode->i_data; - /* ihold ensures nobody can remove inode with our i_data */ - ihold(container_of(dev->dev_mapping, struct inode, i_data)); - inode->i_mapping = dev->dev_mapping; - filp->f_mapping = dev->dev_mapping; - mutex_unlock(&dev->struct_mutex); + if (retcode) + goto err_undo; + atomic_inc(&dev->counts[_DRM_STAT_OPENS]); + if (need_setup) { + retcode = drm_setup(dev); + if (retcode) + goto err_undo; } + return 0; +err_undo: + mutex_lock(&dev->struct_mutex); + filp->f_mapping = old_mapping; + inode->i_mapping = old_mapping; + iput(container_of(dev->dev_mapping, struct inode, i_data)); + dev->dev_mapping = old_mapping; + mutex_unlock(&dev->struct_mutex); + dev->open_count--; return retcode; } EXPORT_SYMBOL(drm_open); |