1 files changed, 56 insertions, 25 deletions

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 9da581452874..88d3368ffddd 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -104,8 +104,8 @@ drm_gem_init(struct drm_device *dev)
 
         if (drm_mm_init(&mm->offset_manager, DRM_FILE_PAGE_OFFSET_START,
                         DRM_FILE_PAGE_OFFSET_SIZE)) {
-                drm_free(mm, sizeof(struct drm_gem_mm), DRM_MEM_MM);
                 drm_ht_remove(&mm->offset_hash);
+                drm_free(mm, sizeof(struct drm_gem_mm), DRM_MEM_MM);
                 return -ENOMEM;
         }
 
@@ -136,7 +136,7 @@ drm_gem_object_alloc(struct drm_device *dev, size_t size)
         obj = kcalloc(1, sizeof(*obj), GFP_KERNEL);
 
         obj->dev = dev;
-        obj->filp = shmem_file_setup("drm mm object", size, 0);
+        obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
         if (IS_ERR(obj->filp)) {
                 kfree(obj);
                 return NULL;
@@ -295,35 +295,37 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data,
                 return -EBADF;
 
 again:
-        if (idr_pre_get(&dev->object_name_idr, GFP_KERNEL) == 0)
-                return -ENOMEM;
+        if (idr_pre_get(&dev->object_name_idr, GFP_KERNEL) == 0) {
+                ret = -ENOMEM;
+                goto err;
+        }
 
         spin_lock(&dev->object_name_lock);
-        if (obj->name) {
-                args->name = obj->name;
+        if (!obj->name) {
+                ret = idr_get_new_above(&dev->object_name_idr, obj, 1,
+                                        &obj->name);
+                args->name = (uint64_t) obj->name;
                 spin_unlock(&dev->object_name_lock);
-                return 0;
-        }
-        ret = idr_get_new_above(&dev->object_name_idr, obj, 1,
-                                 &obj->name);
-        spin_unlock(&dev->object_name_lock);
-        if (ret == -EAGAIN)
-                goto again;
 
-        if (ret != 0) {
-                mutex_lock(&dev->struct_mutex);
-                drm_gem_object_unreference(obj);
-                mutex_unlock(&dev->struct_mutex);
-                return ret;
-        }
+                if (ret == -EAGAIN)
+                        goto again;
 
-        /*
-         * Leave the reference from the lookup around as the
-         * name table now holds one
-         */
-        args->name = (uint64_t) obj->name;
+                if (ret != 0)
+                        goto err;
 
-        return 0;
+                /* Allocate a reference for the name table.  */
+                drm_gem_object_reference(obj);
+        } else {
+                args->name = (uint64_t) obj->name;
+                spin_unlock(&dev->object_name_lock);
+                ret = 0;
+        }
+
+err:
+        mutex_lock(&dev->struct_mutex);
+        drm_gem_object_unreference(obj);
+        mutex_unlock(&dev->struct_mutex);
+        return ret;
 }
 
 /**
@@ -448,6 +450,7 @@ drm_gem_object_handle_free(struct kref *kref)
         spin_lock(&dev->object_name_lock);
         if (obj->name) {
                 idr_remove(&dev->object_name_idr, obj->name);
+                obj->name = 0;
                 spin_unlock(&dev->object_name_lock);
                 /*
                  * The object name held a reference to this object, drop
@@ -460,6 +463,26 @@ drm_gem_object_handle_free(struct kref *kref)
 }
 EXPORT_SYMBOL(drm_gem_object_handle_free);
 
+void drm_gem_vm_open(struct vm_area_struct *vma)
+{
+        struct drm_gem_object *obj = vma->vm_private_data;
+
+        drm_gem_object_reference(obj);
+}
+EXPORT_SYMBOL(drm_gem_vm_open);
+
+void drm_gem_vm_close(struct vm_area_struct *vma)
+{
+        struct drm_gem_object *obj = vma->vm_private_data;
+        struct drm_device *dev = obj->dev;
+
+        mutex_lock(&dev->struct_mutex);
+        drm_gem_object_unreference(obj);
+        mutex_unlock(&dev->struct_mutex);
+}
+EXPORT_SYMBOL(drm_gem_vm_close);
+
+
 /**
  * drm_gem_mmap - memory map routine for GEM objects
  * @filp: DRM file pointer
@@ -521,6 +544,14 @@ int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 #endif
         vma->vm_page_prot = __pgprot(prot);
 
+        /* Take a ref for this mapping of the object, so that the fault
+         * handler can dereference the mmap offset's pointer to the object.
+         * This reference is cleaned up by the corresponding vm_close
+         * (which should happen whether the vma was created by this call, or
+         * by a vm_open due to mremap or partial unmap or whatever).
+         */
+        drm_gem_object_reference(obj);
+
         vma->vm_file = filp;    /* Needed for drm_vm_open() */
         drm_vm_open_locked(vma);