drm: convert to idr_alloc()

Convert to the much saner new idr interface.

* drm_ctxbitmap_next() error handling in drm_addctx() seems broken.
  drm_ctxbitmap_next() return -errno on failure not -1.

[artem.savkov@gmail.com: missing idr_preload_end in drm_gem_flink_ioctl]
[jslaby@suse.cz: fix drm_gem_flink_ioctl() return value]
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David Airlie <airlied@linux.ie>
Signed-off-by: Artem Savkov <artem.savkov@gmail.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 25 insertions, 68 deletions

diff --git a/drivers/gpu/drm/drm_context.c b/drivers/gpu/drm/drm_context.c
index 75f62c5e2a6b..725968d38976 100644
--- a/drivers/gpu/drm/drm_context.c
+++ b/drivers/gpu/drm/drm_context.c
@@ -74,24 +74,13 @@ void drm_ctxbitmap_free(struct drm_device * dev, int ctx_handle)
  */
 static int drm_ctxbitmap_next(struct drm_device * dev)
 {
-        int new_id;
         int ret;
 
-again:
-        if (idr_pre_get(&dev->ctx_idr, GFP_KERNEL) == 0) {
-                DRM_ERROR("Out of memory expanding drawable idr\n");
-                return -ENOMEM;
-        }
         mutex_lock(&dev->struct_mutex);
-        ret = idr_get_new_above(&dev->ctx_idr, NULL,
-                                DRM_RESERVED_CONTEXTS, &new_id);
+        ret = idr_alloc(&dev->ctx_idr, NULL, DRM_RESERVED_CONTEXTS, 0,
+                        GFP_KERNEL);
         mutex_unlock(&dev->struct_mutex);
-        if (ret == -EAGAIN)
-                goto again;
-        else if (ret)
-                return ret;
-
-        return new_id;
+        return ret;
 }
 
 /**
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 99928b933b16..792c3e3795ca 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -266,32 +266,21 @@ char *drm_get_connector_status_name(enum drm_connector_status status)
 static int drm_mode_object_get(struct drm_device *dev,
                                struct drm_mode_object *obj, uint32_t obj_type)
 {
-        int new_id = 0;
         int ret;
 
-again:
-        if (idr_pre_get(&dev->mode_config.crtc_idr, GFP_KERNEL) == 0) {
-                DRM_ERROR("Ran out memory getting a mode number\n");
-                return -ENOMEM;
-        }
-
         mutex_lock(&dev->mode_config.idr_mutex);
-        ret = idr_get_new_above(&dev->mode_config.crtc_idr, obj, 1, &new_id);
-
-        if (!ret) {
+        ret = idr_alloc(&dev->mode_config.crtc_idr, obj, 1, 0, GFP_KERNEL);
+        if (ret >= 0) {
                 /*
                  * Set up the object linking under the protection of the idr
                  * lock so that other users can't see inconsistent state.
                  */
-                obj->id = new_id;
+                obj->id = ret;
                 obj->type = obj_type;
         }
         mutex_unlock(&dev->mode_config.idr_mutex);
 
-        if (ret == -EAGAIN)
-                goto again;
-
-        return ret;
+        return ret < 0 ? ret : 0;
 }
 
 /**
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index e775859f0a83..af779ae19ebf 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -270,21 +270,19 @@ drm_gem_handle_create(struct drm_file *file_priv,
         int ret;
 
         /*
-         * Get the user-visible handle using idr.
+         * Get the user-visible handle using idr.  Preload and perform
+         * allocation under our spinlock.
          */
-again:
-        /* ensure there is space available to allocate a handle */
-        if (idr_pre_get(&file_priv->object_idr, GFP_KERNEL) == 0)
-                return -ENOMEM;
-
-        /* do the allocation under our spinlock */
+        idr_preload(GFP_KERNEL);
         spin_lock(&file_priv->table_lock);
-        ret = idr_get_new_above(&file_priv->object_idr, obj, 1, (int *)handlep);
+
+        ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
+
         spin_unlock(&file_priv->table_lock);
-        if (ret == -EAGAIN)
-                goto again;
-        else if (ret)
+        idr_preload_end();
+        if (ret < 0)
                 return ret;
+        *handlep = ret;
 
         drm_gem_object_handle_reference(obj);
 
@@ -451,29 +449,25 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data,
         if (obj == NULL)
                 return -ENOENT;
 
-again:
-        if (idr_pre_get(&dev->object_name_idr, GFP_KERNEL) == 0) {
-                ret = -ENOMEM;
-                goto err;
-        }
-
+        idr_preload(GFP_KERNEL);
         spin_lock(&dev->object_name_lock);
         if (!obj->name) {
-                ret = idr_get_new_above(&dev->object_name_idr, obj, 1,
-                                        &obj->name);
+                ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT);
+                obj->name = ret;
                 args->name = (uint64_t) obj->name;
                 spin_unlock(&dev->object_name_lock);
+                idr_preload_end();
 
-                if (ret == -EAGAIN)
-                        goto again;
-                else if (ret)
+                if (ret < 0)
                         goto err;
+                ret = 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);
+                idr_preload_end();
                 ret = 0;
         }
 
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index 200e104f1fa0..7d30802a018f 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -109,7 +109,6 @@ EXPORT_SYMBOL(drm_ut_debug_printk);
 
 static int drm_minor_get_id(struct drm_device *dev, int type)
 {
-        int new_id;
         int ret;
         int base = 0, limit = 63;
 
@@ -121,25 +120,11 @@ static int drm_minor_get_id(struct drm_device *dev, int type)
                 limit = base + 255;
         }
 
-again:
-        if (idr_pre_get(&drm_minors_idr, GFP_KERNEL) == 0) {
-                DRM_ERROR("Out of memory expanding drawable idr\n");
-                return -ENOMEM;
-        }
         mutex_lock(&dev->struct_mutex);
-        ret = idr_get_new_above(&drm_minors_idr, NULL,
-                                base, &new_id);
+        ret = idr_alloc(&drm_minors_idr, NULL, base, limit, GFP_KERNEL);
         mutex_unlock(&dev->struct_mutex);
-        if (ret == -EAGAIN)
-                goto again;
-        else if (ret)
-                return ret;
 
-        if (new_id >= limit) {
-                idr_remove(&drm_minors_idr, new_id);
-                return -EINVAL;
-        }
-        return new_id;
+        return ret == -ENOSPC ? -EINVAL : ret;
 }
 
 struct drm_master *drm_master_create(struct drm_minor *minor)