nfsd: fix callback restarts
Checking the rpc_client pointer is not a reliable way to detect
backchannel changes: cl_cb_client is changed only after shutting down
the rpc client, so the condition cl_cb_client = tk_client will always be
true.
Check the RPC_TASK_KILLED flag instead, and rewrite the code to avoid
the buggy cl_callbacks list and fix the lifetime rules due to double
calls of the ->prepare callback operations method for this retry case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index e791985..dbc4f85 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -63,13 +63,12 @@
struct nfsd4_callback {
struct nfs4_client *cb_clp;
- struct list_head cb_per_client;
u32 cb_minorversion;
struct rpc_message cb_msg;
struct nfsd4_callback_ops *cb_ops;
struct work_struct cb_work;
int cb_status;
- bool cb_done;
+ bool cb_need_restart;
};
struct nfsd4_callback_ops {
@@ -334,7 +333,6 @@
int cl_cb_state;
struct nfsd4_callback cl_cb_null;
struct nfsd4_session *cl_cb_session;
- struct list_head cl_callbacks; /* list of in-progress callbacks */
/* for all client information that callback code might need: */
spinlock_t cl_lock;
