RDMA/core: Allow the ioctl layer to abort a fully created uobject

While creating a uobject every create reaches a point where the uobject is
fully initialized. For ioctls that go on to copy_to_user this means they
need to open code the destruction of a fully created uobject - ie the
RDMA_REMOVE_DESTROY sort of flow.

Open coding this creates bugs, eg the CQ does not properly flush the
events list when it does its error unwind.

Provide a uverbs_finalize_uobj_create() function which indicates that the
uobject is fully initialized and that abort should call to destroy_hw to
destroy the uobj->object and related.

Methods can call this function if they go on to have error cases after
setting uobj->object. Once done those error cases can simply do return,
without an error unwind.

Link: https://lore.kernel.org/r/20200519072711.257271-2-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

4 files changed, 11 insertions, 2 deletions

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 641f4751b062..c988e9205cf9 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1491,6 +1491,11 @@ enum rdma_remove_reason {
 	RDMA_REMOVE_DRIVER_REMOVE,
 	/* uobj is being cleaned-up before being committed */
 	RDMA_REMOVE_ABORT,
+	/*
+	 * uobj has been fully created, with the uobj->object set, but is being
+	 * cleaned up before being comitted
+	 */
+	RDMA_REMOVE_ABORT_HWOBJ,
 };
 
 struct ib_rdmacg_object {
diff --git a/include/rdma/uverbs_ioctl.h b/include/rdma/uverbs_ioctl.h
index 9f3b1e004046..5bd2b037e914 100644
--- a/include/rdma/uverbs_ioctl.h
+++ b/include/rdma/uverbs_ioctl.h
@@ -737,6 +737,9 @@ uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
 	return attr->ptr_attr.len;
 }
 
+void uverbs_finalize_uobj_create(const struct uverbs_attr_bundle *attrs_bundle,
+				 u16 idx);
+
 /*
  * uverbs_attr_ptr_get_array_size() - Get array size pointer by a ptr
  * attribute.
diff --git a/include/rdma/uverbs_std_types.h b/include/rdma/uverbs_std_types.h
index 1b28ce1aba07..d6784be27e4b 100644
--- a/include/rdma/uverbs_std_types.h
+++ b/include/rdma/uverbs_std_types.h
@@ -107,7 +107,7 @@ static inline void uobj_put_write(struct ib_uobject *uobj)
 static inline void uobj_alloc_abort(struct ib_uobject *uobj,
 				    struct uverbs_attr_bundle *attrs)
 {
-	rdma_alloc_abort_uobject(uobj, attrs);
+	rdma_alloc_abort_uobject(uobj, attrs, false);
 }
 
 static inline struct ib_uobject *
diff --git a/include/rdma/uverbs_types.h b/include/rdma/uverbs_types.h
index f1cbdae67250..c15b298aa62f 100644
--- a/include/rdma/uverbs_types.h
+++ b/include/rdma/uverbs_types.h
@@ -139,7 +139,8 @@ void rdma_lookup_put_uobject(struct ib_uobject *uobj,
 struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_api_object *obj,
 					    struct uverbs_attr_bundle *attrs);
 void rdma_alloc_abort_uobject(struct ib_uobject *uobj,
-			      struct uverbs_attr_bundle *attrs);
+			      struct uverbs_attr_bundle *attrs,
+			      bool hw_obj_valid);
 void rdma_alloc_commit_uobject(struct ib_uobject *uobj,
 			       struct uverbs_attr_bundle *attrs);