drm/via: track user->memblock mapping with idr

Massive indirection through a hashtable for a simple key->pointer
look-up actually just adds bloat.

v2: Drop the misleading comment noted by Chris Wilson.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

3 files changed, 47 insertions, 14 deletions

diff --git a/drivers/gpu/drm/via/via_drv.h b/drivers/gpu/drm/via/via_drv.h
index 9cf87d912325..108ea71f399d 100644
--- a/drivers/gpu/drm/via/via_drv.h
+++ b/drivers/gpu/drm/via/via_drv.h
@@ -91,6 +91,8 @@ typedef struct drm_via_private {
         struct drm_sman sman;
         int vram_initialized;
         int agp_initialized;
+        /** Mapping of userspace keys to mm objects */
+        struct idr object_idr;
         unsigned long vram_offset;
         unsigned long agp_offset;
         drm_via_blitq_t blit_queues[VIA_NUM_BLIT_ENGINES];
diff --git a/drivers/gpu/drm/via/via_map.c b/drivers/gpu/drm/via/via_map.c
index 6cca9a709f7a..b09f6596f15f 100644
--- a/drivers/gpu/drm/via/via_map.c
+++ b/drivers/gpu/drm/via/via_map.c
@@ -104,6 +104,7 @@ int via_driver_load(struct drm_device *dev, unsigned long chipset)
 
         dev_priv->chipset = chipset;
 
+        idr_init(&dev->object_name_idr);
         ret = drm_sman_init(&dev_priv->sman, 2, 12, 8);
         if (ret) {
                 kfree(dev_priv);
diff --git a/drivers/gpu/drm/via/via_mm.c b/drivers/gpu/drm/via/via_mm.c
index e0110bc27606..e6f2b6371b4e 100644
--- a/drivers/gpu/drm/via/via_mm.c
+++ b/drivers/gpu/drm/via/via_mm.c
@@ -118,7 +118,7 @@ int via_mem_alloc(struct drm_device *dev, void *data,
                   struct drm_file *file)
 {
         drm_via_mem_t *mem = data;
-        int retval = 0;
+        int retval = 0, user_key;
         struct drm_memblock_item *item;
         drm_via_private_t *dev_priv = (drm_via_private_t *) dev->dev_private;
         struct via_file_private *file_priv = file->driver_priv;
@@ -139,23 +139,44 @@ int via_mem_alloc(struct drm_device *dev, void *data,
 
         tmpSize = (mem->size + VIA_MM_ALIGN_MASK) >> VIA_MM_ALIGN_SHIFT;
         item = drm_sman_alloc(&dev_priv->sman, mem->type, tmpSize, 0, 0);
+        if (!item) {
+                retval = -ENOMEM;
+                goto fail_alloc;
+        }
 
-        if (item) {
-                list_add(&item->owner_list, &file_priv->obj_list);
-                mem->offset = ((mem->type == VIA_MEM_VIDEO) ?
-                              dev_priv->vram_offset : dev_priv->agp_offset) +
-                    (item->mm->
-                     offset(item->mm, item->mm_info) << VIA_MM_ALIGN_SHIFT);
-                mem->index = item->user_hash.key;
-        } else {
-                mem->offset = 0;
-                mem->size = 0;
-                mem->index = 0;
-                DRM_DEBUG("Video memory allocation failed\n");
+again:
+        if (idr_pre_get(&dev_priv->object_idr, GFP_KERNEL) == 0) {
                 retval = -ENOMEM;
+                goto fail_idr;
         }
+
+        retval = idr_get_new_above(&dev_priv->object_idr, item, 1, &user_key);
+        if (retval == -EAGAIN)
+                goto again;
+        if (retval)
+                goto fail_idr;
+
+        list_add(&item->owner_list, &file_priv->obj_list);
         mutex_unlock(&dev->struct_mutex);
 
+        mem->offset = ((mem->type == VIA_MEM_VIDEO) ?
+                      dev_priv->vram_offset : dev_priv->agp_offset) +
+            (item->mm->
+             offset(item->mm, item->mm_info) << VIA_MM_ALIGN_SHIFT);
+        mem->index = user_key;
+
+        return 0;
+
+fail_idr:
+        drm_sman_free(item);
+fail_alloc:
+        mutex_unlock(&dev->struct_mutex);
+
+        mem->offset = 0;
+        mem->size = 0;
+        mem->index = 0;
+        DRM_DEBUG("Video memory allocation failed\n");
+
         return retval;
 }
 
@@ -163,11 +184,20 @@ int via_mem_free(struct drm_device *dev, void *data, struct drm_file *file_priv)
 {
         drm_via_private_t *dev_priv = dev->dev_private;
         drm_via_mem_t *mem = data;
+        struct drm_memblock_item *obj;
         int ret;
 
         mutex_lock(&dev->struct_mutex);
-        ret = drm_sman_free_key(&dev_priv->sman, mem->index);
+        obj = idr_find(&dev_priv->object_idr, mem->index);
+        if (obj == NULL) {
+                mutex_unlock(&dev->struct_mutex);
+                return -EINVAL;
+        }
+
+        idr_remove(&dev_priv->object_idr, mem->index);
+        drm_sman_free(obj);
         mutex_unlock(&dev->struct_mutex);
+
         DRM_DEBUG("free = 0x%lx\n", mem->index);
 
         return ret;