From: Chuck Lever <chuck.lever@oracle.com>
Date: Tue, 4 Sep 2018 11:45:14 -0400
Subject: RDMA/core: Document CM @event_handler function
Patch-mainline: v4.20-rc1
Git-commit: 4269024639f6ff9a1967c4bfa5a2ba7d9853384a
References: bsc#1103992 FATE#326009

Code audit suggests that the RDMA CM event handler callback function is
_always_ invoked in a context that is safe to block. That's important for
consumer implementers to know, so document that in the comment before
rdma_create_id (where the handler function is set up by the consumer).

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 include/rdma/rdma_cm.h |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/include/rdma/rdma_cm.h
+++ b/include/rdma/rdma_cm.h
@@ -152,7 +152,11 @@ struct rdma_cm_id *__rdma_create_id(stru
  * @ps: RDMA port space.
  * @qp_type: type of queue pair associated with the id.
  *
- * The id holds a reference on the network namespace until it is destroyed.
+ * Returns a new rdma_cm_id. The id holds a reference on the network
+ * namespace until it is destroyed.
+ *
+ * The event handler callback serializes on the id's mutex and is
+ * allowed to sleep.
  */
 #define rdma_create_id(net, event_handler, context, ps, qp_type) \
 	__rdma_create_id((net), (event_handler), (context), (ps), (qp_type), \