Merge tag 'afs-next-20190915' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "Here's a set of patches for AFS. The first three are trivial, deleting
  unused symbols and rolling out a wrapper function.

  The fourth and fifth patches make use of the previously added RCU-safe
  request_key facility to allow afs_permission() and afs_d_revalidate()
  to attempt to operate without dropping out of RCU-mode pathwalk. Under
  certain conditions, such as conflict with another client, we still
  have to drop out anyway, take a lock and consult the server"

* tag 'afs-next-20190915' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Support RCU pathwalk
  afs: Provide an RCU-capable key lookup
  afs: Use afs_extract_discard() rather than iov_iter_discard()
  afs: remove unused variable 'afs_zero_fid'
  afs: remove unused variable 'afs_voltypes'

1 files changed, 13 insertions, 1 deletions

diff --git a/include/linux/key.h b/include/linux/key.h
index 50028338a4cc..6cf8e71cf8b7 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -324,7 +324,7 @@ static inline struct key *request_key(struct key_type *type,
 }
 
 #ifdef CONFIG_NET
-/*
+/**
  * request_key_net - Request a key for a net namespace and wait for construction
  * @type: Type of key.
  * @description: The searchable description of the key.
@@ -341,6 +341,18 @@ static inline struct key *request_key(struct key_type *type,
  */
 #define request_key_net(type, description, net, callout_info) \
 	request_key_tag(type, description, net->key_domain, callout_info);
+
+/**
+ * request_key_net_rcu - Request a key for a net namespace under RCU conditions
+ * @type: Type of key.
+ * @description: The searchable description of the key.
+ * @net: The network namespace that is the key's domain of operation.
+ *
+ * As for request_key_rcu() except that only keys that operate the specified
+ * network namespace are used.
+ */
+#define request_key_net_rcu(type, description, net) \
+	request_key_rcu(type, description, net->key_domain);
 #endif /* CONFIG_NET */
 
 extern int wait_for_key_construction(struct key *key, bool intr);