[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