[PATCH 11/19] drm: do not remove a render node in use

[Ilija Hadzic]

Keep track of per-node open count and do not allow removal
of a render node in use.

Signed-off-by: Ilija Hadzic <ihadzic at research.bell-labs.com>
---
 drivers/gpu/drm/drm_fops.c |    2 ++
 drivers/gpu/drm/drm_stub.c |    2 ++
 include/drm/drmP.h         |    1 +
 3 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index 4498d76..686236f 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -136,6 +136,7 @@ int drm_open(struct inode *inode, struct file *filp)
 	retcode = drm_open_helper(filp, minor);
 	if (!retcode) {
 		atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
+		minor->open_count++;
 		if (!dev->open_count++)
 			retcode = drm_setup(dev);
 	}
@@ -573,6 +574,7 @@ int drm_release(struct inode *inode, struct file *filp)
 	 */
 
 	atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
+	file_priv->minor->open_count--;
 	if (!--dev->open_count) {
 		if (atomic_read(&dev->ioctl_count)) {
 			DRM_ERROR("Device busy: %d\n",
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index 6629dd7..5ebc8bc 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -426,6 +426,8 @@ int drm_destroy_render_node(struct drm_device *dev, int index)
 
 	list_for_each_entry_safe(node, tmp, &dev->render_node_list, list) {
 		if (node->minor->index == index) {
+			if (node->minor->open_count)
+				return -EBUSY;
 			list_del(&node->list);
 			drm_put_minor(&node->minor);
 			kfree(node);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 1131fd4..981f005 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -983,6 +983,7 @@ struct drm_info_node {
 struct drm_minor {
 	int index;			/**< Minor device number */
 	int type;                       /**< Control or render */
+	int open_count;
 	dev_t device;			/**< Device number for mknod */
 	struct device kdev;		/**< Linux device */
 	struct drm_device *dev;
-- 
1.7.8.5