5 files changed, 13 insertions, 18 deletions

diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index d25a61739a7b..5062eec673f1 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -140,12 +140,12 @@ int drm_open(struct inode *inode, struct file *filp)
         }
         if (!retcode) {
                 mutex_lock(&dev->struct_mutex);
-                if (minor->type == DRM_MINOR_LEGACY) {
-                        if (dev->dev_mapping == NULL)
-                                dev->dev_mapping = inode->i_mapping;
-                        else if (dev->dev_mapping != inode->i_mapping)
-                                retcode = -ENODEV;
-                }
+                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);
         }
 
@@ -509,6 +509,9 @@ int drm_release(struct inode *inode, struct file *filp)
                 }
         }
 
+        BUG_ON(dev->dev_mapping == NULL);
+        iput(container_of(dev->dev_mapping, struct inode, i_data));
+
         /* drop the reference held my the file priv */
         drm_master_put(&file_priv->master);
         file_priv->is_master = 0;
diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c
index 30f542316944..fe3f5a821b84 100644
--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -207,8 +207,7 @@ nouveau_gem_ioctl_new(struct drm_device *dev, void *data,
         struct nouveau_bo *nvbo = NULL;
         int ret = 0;
 
-        if (unlikely(dev_priv->ttm.bdev.dev_mapping == NULL))
-                dev_priv->ttm.bdev.dev_mapping = dev_priv->dev->dev_mapping;
+        dev_priv->ttm.bdev.dev_mapping = dev->dev_mapping;
 
         if (!dev_priv->engine.vram.flags_valid(dev, req->info.tile_flags)) {
                 NV_ERROR(dev, "bad page flags: 0x%08x\n", req->info.tile_flags);
diff --git a/drivers/gpu/drm/radeon/radeon_object.c b/drivers/gpu/drm/radeon/radeon_object.c
index 6ecb2006e27e..1f77a5afc011 100644
--- a/drivers/gpu/drm/radeon/radeon_object.c
+++ b/drivers/gpu/drm/radeon/radeon_object.c
@@ -115,9 +115,7 @@ int radeon_bo_create(struct radeon_device *rdev,
 
         size = ALIGN(size, PAGE_SIZE);
 
-        if (unlikely(rdev->mman.bdev.dev_mapping == NULL)) {
-                rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping;
-        }
+        rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping;
         if (kernel) {
                 type = ttm_bo_type_kernel;
         } else if (sg) {
diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index 0881131a0388..5b71c716d83f 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -734,9 +734,7 @@ int radeon_ttm_init(struct radeon_device *rdev)
         }
         DRM_INFO("radeon: %uM of GTT memory ready.\n",
                  (unsigned)(rdev->mc.gtt_size / (1024 * 1024)));
-        if (unlikely(rdev->mman.bdev.dev_mapping == NULL)) {
-                rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping;
-        }
+        rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping;
 
         r = radeon_ttm_debugfs_init(rdev);
         if (r) {
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index 5d5632f5265b..4d9edead01ac 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -769,10 +769,7 @@ static int vmw_driver_open(struct drm_device *dev, struct drm_file *file_priv)
                 goto out_no_tfile;
 
         file_priv->driver_priv = vmw_fp;
-
-        if (unlikely(dev_priv->bdev.dev_mapping == NULL))
-                dev_priv->bdev.dev_mapping =
-                        file_priv->filp->f_path.dentry->d_inode->i_mapping;
+        dev_priv->bdev.dev_mapping = dev->dev_mapping;
 
         return 0;