drm/msm: Remove unnecessary struct_mutex

The struct_mutex locking is a remnant from the days before per-obj locks,
and no longer needed.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20211109181117.591148-2-robdclark@gmail.comSigned-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/msm_debugfs.c

@@ -134,8 +134,10 @@ DEFINE_SIMPLE_ATTRIBUTE(shrink_fops,
 			"0x%08llx\n");
 
 
-static int msm_gem_show(struct drm_device *dev, struct seq_file *m)
+static int msm_gem_show(struct seq_file *m, void *arg)
 {
+	struct drm_info_node *node = (struct drm_info_node *) m->private;
+	struct drm_device *dev = node->minor->dev;
 	struct msm_drm_private *priv = dev->dev_private;
 	int ret;
 
@@ -150,8 +152,10 @@ static int msm_gem_show(struct drm_device *dev, struct seq_file *m)
 	return 0;
 }
 
-static int msm_mm_show(struct drm_device *dev, struct seq_file *m)
+static int msm_mm_show(struct seq_file *m, void *arg)
 {
+	struct drm_info_node *node = (struct drm_info_node *) m->private;
+	struct drm_device *dev = node->minor->dev;
 	struct drm_printer p = drm_seq_file_printer(m);
 
 	drm_mm_print(&dev->vma_offset_manager->vm_addr_space_mm, &p);
@@ -159,8 +163,10 @@ static int msm_mm_show(struct drm_device *dev, struct seq_file *m)
 	return 0;
 }
 
-static int msm_fb_show(struct drm_device *dev, struct seq_file *m)
+static int msm_fb_show(struct seq_file *m, void *arg)
 {
+	struct drm_info_node *node = (struct drm_info_node *) m->private;
+	struct drm_device *dev = node->minor->dev;
 	struct msm_drm_private *priv = dev->dev_private;
 	struct drm_framebuffer *fb, *fbdev_fb = NULL;
 
@@ -183,29 +189,10 @@ static int msm_fb_show(struct drm_device *dev, struct seq_file *m)
 	return 0;
 }
 
-static int show_locked(struct seq_file *m, void *arg)
-{
-	struct drm_info_node *node = (struct drm_info_node *) m->private;
-	struct drm_device *dev = node->minor->dev;
-	int (*show)(struct drm_device *dev, struct seq_file *m) =
-			node->info_ent->data;
-	int ret;
-
-	ret = mutex_lock_interruptible(&dev->struct_mutex);
-	if (ret)
-		return ret;
-
-	ret = show(dev, m);
-
-	mutex_unlock(&dev->struct_mutex);
-
-	return ret;
-}
-
 static struct drm_info_list msm_debugfs_list[] = {
-		{"gem", show_locked, 0, msm_gem_show},
-		{ "mm", show_locked, 0, msm_mm_show },
-		{ "fb", show_locked, 0, msm_fb_show },
+		{"gem", msm_gem_show},
+		{ "mm", msm_mm_show },
+		{ "fb", msm_fb_show },
 };
 
 static int late_init_minor(struct drm_minor *minor)

drivers/gpu/drm/msm/msm_fbdev.c

@@ -81,8 +81,6 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 
 	bo = msm_framebuffer_bo(fb, 0);
 
-	mutex_lock(&dev->struct_mutex);
-
 	/*
 	 * NOTE: if we can be guaranteed to be able to map buffer
 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
@@ -91,14 +89,14 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
 	if (ret) {
 		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
-		goto fail_unlock;
+		goto fail;
 	}
 
 	fbi = drm_fb_helper_alloc_fbi(helper);
 	if (IS_ERR(fbi)) {
 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
 		ret = PTR_ERR(fbi);
-		goto fail_unlock;
+		goto fail;
 	}
 
 	DBG("fbi=%p, dev=%p", fbi, dev);
@@ -115,7 +113,7 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 	fbi->screen_base = msm_gem_get_vaddr(bo);
 	if (IS_ERR(fbi->screen_base)) {
 		ret = PTR_ERR(fbi->screen_base);
-		goto fail_unlock;
+		goto fail;
 	}
 	fbi->screen_size = bo->size;
 	fbi->fix.smem_start = paddr;
@@ -124,12 +122,9 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
 	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
 
-	mutex_unlock(&dev->struct_mutex);
-
 	return 0;
 
-fail_unlock:
-	mutex_unlock(&dev->struct_mutex);
+fail:
 	drm_framebuffer_remove(fb);
 	return ret;
 }