[PATCH 4/6] drm: provide management functions for drm_file

[David Herrmann <dh.herrmann@gmail.com>]

Rather than doing drm_file allocation/destruction right in the fops, lets
provide separate helpers. This decouples drm_file management from the
still-mandatory drm-fops. It prepares for use of drm_file without the
fops, both by possible separate fops implementations and APIs (not that I
am aware of any such plans), and more importantly from in-kernel use where
no real file is available.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
---
 drivers/gpu/drm/drm_drv.c      | 135 +++++++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_fops.c     | 132 +++-------------------------------------
 drivers/gpu/drm/drm_internal.h |   4 ++
 3 files changed, 147 insertions(+), 124 deletions(-)

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 57ce973..9ab0016 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -95,6 +95,141 @@ void drm_ut_debug_printk(const char *function_name, const char *format, ...)
 }
 EXPORT_SYMBOL(drm_ut_debug_printk);
 
+/**
+ * drm_file_alloc - allocate file context
+ * @minor: minor to allocate on
+ *
+ * This allocates a new DRM file context. It is not linked into any context and
+ * can be used by the caller freely. Note that the context keeps a pointer to
+ * @minor, so it must be freed before @minor is.
+ *
+ * The legacy paths might require the drm_global_mutex to be held.
+ *
+ * RETURNS:
+ * Pointer to newly allocated context, ERR_PTR on failure.
+ */
+struct drm_file *drm_file_alloc(struct drm_minor *minor)
+{
+	struct drm_device *dev = minor->dev;
+	struct drm_file *file;
+	int ret;
+
+	file = kzalloc(sizeof(*file), GFP_KERNEL);
+	if (!file)
+		return ERR_PTR(-ENOMEM);
+
+	file->pid = get_pid(task_pid(current));
+	file->minor = minor;
+	file->authenticated = capable(CAP_SYS_ADMIN); /* legacy compat */
+	INIT_LIST_HEAD(&file->lhead);
+	INIT_LIST_HEAD(&file->fbs);
+	mutex_init(&file->fbs_lock);
+	INIT_LIST_HEAD(&file->blobs);
+	INIT_LIST_HEAD(&file->pending_event_list);
+	INIT_LIST_HEAD(&file->event_list);
+	init_waitqueue_head(&file->event_wait);
+	file->event_space = 4096; /* set aside 4k for event buffer */
+	mutex_init(&file->event_read_lock);
+
+	if (drm_core_check_feature(dev, DRIVER_GEM))
+		drm_gem_open(dev, file);
+	if (drm_core_check_feature(dev, DRIVER_PRIME))
+		drm_prime_init_file_private(&file->prime);
+
+	if (dev->driver->open) {
+		ret = dev->driver->open(dev, file);
+		if (ret < 0)
+			goto out_prime_destroy;
+	}
+
+	if (drm_is_primary_client(file)) {
+		ret = drm_master_open(file);
+		if (ret)
+			goto out_close;
+	}
+
+	return file;
+
+out_close:
+	if (dev->driver->postclose)
+		dev->driver->postclose(dev, file);
+out_prime_destroy:
+	if (drm_core_check_feature(dev, DRIVER_PRIME))
+		drm_prime_destroy_file_private(&file->prime);
+	if (drm_core_check_feature(dev, DRIVER_GEM))
+		drm_gem_release(dev, file);
+	put_pid(file->pid);
+	kfree(file);
+	return ERR_PTR(ret);
+}
+
+/**
+ * drm_file_free - free file context
+ * @file: context to free, or NULL
+ *
+ * This destroys and deallocates a DRM file context previously allocated via
+ * drm_file_alloc(). The caller must make sure to unlink it from any contexts
+ * before calling this.
+ *
+ * The legacy paths might require the drm_global_mutex to be held.
+ *
+ * If NULL is passed, this is a no-op.
+ *
+ * RETURNS:
+ * 0 on success, or error code on failure.
+ */
+void drm_file_free(struct drm_file *file)
+{
+	struct drm_pending_event *e;
+	struct drm_device *dev;
+
+	if (!file)
+		return;
+
+	dev = file->minor->dev;
+
+	if (dev->driver->preclose)
+		dev->driver->preclose(dev, file);
+	if (!drm_core_check_feature(dev, DRIVER_MODESET))
+		drm_legacy_lock_release(dev, file->legacy_filp);
+	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
+		drm_legacy_reclaim_buffers(dev, file);
+
+	spin_lock_irq(&dev->event_lock);
+	while ((e = list_first_entry_or_null(&file->pending_event_list,
+					     struct drm_pending_event,
+					     pending_link))) {
+		list_del(&e->pending_link);
+		e->file_priv = NULL;
+	}
+	while ((e = list_first_entry_or_null(&file->event_list,
+					     struct drm_pending_event, link))) {
+		list_del(&e->link);
+		kfree(e);
+	}
+	spin_unlock_irq(&dev->event_lock);
+
+	drm_legacy_ctxbitmap_flush(dev, file);
+
+	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
+		drm_fb_release(file);
+		drm_property_destroy_user_blobs(dev, file);
+	}
+
+	if (drm_core_check_feature(dev, DRIVER_GEM))
+		drm_gem_release(dev, file);
+	if (drm_is_primary_client(file))
+		drm_master_release(file);
+	if (dev->driver->postclose)
+		dev->driver->postclose(dev, file);
+	if (drm_core_check_feature(dev, DRIVER_PRIME))
+		drm_prime_destroy_file_private(&file->prime);
+
+	WARN_ON(!list_empty(&file->event_list));
+	put_pid(file->pid);
+	kfree(file);
+}
+
 /*
  * DRM Minors
  * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index 69ef23c..359c636 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -182,7 +182,6 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor)
 {
 	struct drm_device *dev = minor->dev;
 	struct drm_file *priv;
-	int ret;
 
 	if (filp->f_flags & O_EXCL)
 		return -EBUSY;	/* No exclusive opens */
@@ -193,47 +192,12 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor)
 
 	DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor->index);
 
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-	if (!priv)
-		return -ENOMEM;
+	priv = drm_file_alloc(minor);
+	if (IS_ERR(priv))
+		return PTR_ERR(priv);
 
-	filp->private_data = priv;
 	priv->legacy_filp = filp;
-	priv->pid = get_pid(task_pid(current));
-	priv->minor = minor;
-
-	/* for compatibility root is always authenticated */
-	priv->authenticated = capable(CAP_SYS_ADMIN);
-	priv->lock_count = 0;
-
-	INIT_LIST_HEAD(&priv->lhead);
-	INIT_LIST_HEAD(&priv->fbs);
-	mutex_init(&priv->fbs_lock);
-	INIT_LIST_HEAD(&priv->blobs);
-	INIT_LIST_HEAD(&priv->pending_event_list);
-	INIT_LIST_HEAD(&priv->event_list);
-	init_waitqueue_head(&priv->event_wait);
-	priv->event_space = 4096; /* set aside 4k for event buffer */
-
-	mutex_init(&priv->event_read_lock);
-
-	if (drm_core_check_feature(dev, DRIVER_GEM))
-		drm_gem_open(dev, priv);
-
-	if (drm_core_check_feature(dev, DRIVER_PRIME))
-		drm_prime_init_file_private(&priv->prime);
-
-	if (dev->driver->open) {
-		ret = dev->driver->open(dev, priv);
-		if (ret < 0)
-			goto out_prime_destroy;
-	}
-
-	if (drm_is_primary_client(priv)) {
-		ret = drm_master_open(priv);
-		if (ret)
-			goto out_close;
-	}
+	filp->private_data = priv;
 
 	mutex_lock(&dev->filelist_mutex);
 	list_add(&priv->lhead, &dev->filelist);
@@ -260,43 +224,6 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor)
 #endif
 
 	return 0;
-
-out_close:
-	if (dev->driver->postclose)
-		dev->driver->postclose(dev, priv);
-out_prime_destroy:
-	if (drm_core_check_feature(dev, DRIVER_PRIME))
-		drm_prime_destroy_file_private(&priv->prime);
-	if (drm_core_check_feature(dev, DRIVER_GEM))
-		drm_gem_release(dev, priv);
-	put_pid(priv->pid);
-	kfree(priv);
-	filp->private_data = NULL;
-	return ret;
-}
-
-static void drm_events_release(struct drm_file *file_priv)
-{
-	struct drm_device *dev = file_priv->minor->dev;
-	struct drm_pending_event *e, *et;
-	unsigned long flags;
-
-	spin_lock_irqsave(&dev->event_lock, flags);
-
-	/* Unlink pending events */
-	list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
-				 pending_link) {
-		list_del(&e->pending_link);
-		e->file_priv = NULL;
-	}
-
-	/* Remove unconsumed events */
-	list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
-		list_del(&e->link);
-		kfree(e);
-	}
-
-	spin_unlock_irqrestore(&dev->event_lock, flags);
 }
 
 /*
@@ -370,59 +297,16 @@ int drm_release(struct inode *inode, struct file *filp)
 
 	mutex_lock(&drm_global_mutex);
 
-	DRM_DEBUG("open_count = %d\n", dev->open_count);
-
-	mutex_lock(&dev->filelist_mutex);
-	list_del(&file_priv->lhead);
-	mutex_unlock(&dev->filelist_mutex);
-
-	if (dev->driver->preclose)
-		dev->driver->preclose(dev, file_priv);
-
-	/* ========================================================
-	 * Begin inline drm_release
-	 */
-
 	DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 		  task_pid_nr(current),
 		  (long)old_encode_dev(file_priv->minor->kdev->devt),
 		  dev->open_count);
 
-	if (!drm_core_check_feature(dev, DRIVER_MODESET))
-		drm_legacy_lock_release(dev, filp);
-
-	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
-		drm_legacy_reclaim_buffers(dev, file_priv);
-
-	drm_events_release(file_priv);
-
-	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
-		drm_fb_release(file_priv);
-		drm_property_destroy_user_blobs(dev, file_priv);
-	}
-
-	if (drm_core_check_feature(dev, DRIVER_GEM))
-		drm_gem_release(dev, file_priv);
-
-	drm_legacy_ctxbitmap_flush(dev, file_priv);
-
-	if (drm_is_primary_client(file_priv))
-		drm_master_release(file_priv);
-
-	if (dev->driver->postclose)
-		dev->driver->postclose(dev, file_priv);
-
-	if (drm_core_check_feature(dev, DRIVER_PRIME))
-		drm_prime_destroy_file_private(&file_priv->prime);
-
-	WARN_ON(!list_empty(&file_priv->event_list));
-
-	put_pid(file_priv->pid);
-	kfree(file_priv);
+	mutex_lock(&dev->filelist_mutex);
+	list_del(&file_priv->lhead);
+	mutex_unlock(&dev->filelist_mutex);
 
-	/* ========================================================
-	 * End inline drm_release
-	 */
+	drm_file_free(file_priv);
 
 	if (!--dev->open_count) {
 		drm_lastclose(dev);
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index b86dc9b..9b66cc4 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -28,6 +28,10 @@ extern unsigned int drm_timestamp_monotonic;
 extern struct mutex drm_global_mutex;
 void drm_lastclose(struct drm_device *dev);
 
+/* drm_drv.c */
+struct drm_file *drm_file_alloc(struct drm_minor *minor);
+void drm_file_free(struct drm_file *file);
+
 /* drm_pci.c */
 int drm_irq_by_busid(struct drm_device *dev, void *data,
 		     struct drm_file *file_priv);
-- 
2.9.3

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel