Merge tag 'rxrpc-rewrite-20170109' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
afs: Refcount afs_call struct

These patches provide some tracepoints for AFS and fix a potential leak by
adding refcounting to the afs_call struct.

The patches are:

 (1) Add some tracepoints for logging incoming calls and monitoring
     notifications from AF_RXRPC and data reception.

 (2) Get rid of afs_wait_mode as it didn't turn out to be as useful as
     initially expected.  It can be brought back later if needed.  This
     clears some stuff out that I don't then need to fix up in (4).

 (3) Allow listen(..., 0) to be used to disable listening.  This makes
     shutting down the AFS cache manager server in the kernel much easier
     and the accounting simpler as we can then be sure that (a) all
     preallocated afs_call structs are relesed and (b) no new incoming
     calls are going to be started.

     For the moment, listening cannot be reenabled.

 (4) Add refcounting to the afs_call struct to fix a potential multiple
     release detected by static checking and add a tracepoint to follow the
     lifecycle of afs_call objects.
====================

Signed-off-by: David S. Miller <[email protected]>

Author: davem330

fs/afs/callback.c

@@ -343,7 +343,7 @@ void afs_dispatch_give_up_callbacks(struct work_struct *work)
 	 *   had callbacks entirely, and the server will call us later to break
 	 *   them
 	 */
-	afs_fs_give_up_callbacks(server, &afs_async_call);
+	afs_fs_give_up_callbacks(server, true);
 }
 
 /*

fs/afs/cmservice.c

@@ -24,65 +24,86 @@ static int afs_deliver_cb_callback(struct afs_call *);
 static int afs_deliver_cb_probe_uuid(struct afs_call *);
 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
 static void afs_cm_destructor(struct afs_call *);
+static void SRXAFSCB_CallBack(struct work_struct *);
+static void SRXAFSCB_InitCallBackState(struct work_struct *);
+static void SRXAFSCB_Probe(struct work_struct *);
+static void SRXAFSCB_ProbeUuid(struct work_struct *);
+static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
+
+#define CM_NAME(name) \
+	const char afs_SRXCB##name##_name[] __tracepoint_string =	\
+		"CB." #name
 
 /*
  * CB.CallBack operation type
  */
+static CM_NAME(CallBack);
 static const struct afs_call_type afs_SRXCBCallBack = {
-	.name		= "CB.CallBack",
+	.name		= afs_SRXCBCallBack_name,
 	.deliver	= afs_deliver_cb_callback,
 	.abort_to_error	= afs_abort_to_error,
 	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_CallBack,
 };
 
 /*
  * CB.InitCallBackState operation type
  */
+static CM_NAME(InitCallBackState);
 static const struct afs_call_type afs_SRXCBInitCallBackState = {
-	.name		= "CB.InitCallBackState",
+	.name		= afs_SRXCBInitCallBackState_name,
 	.deliver	= afs_deliver_cb_init_call_back_state,
 	.abort_to_error	= afs_abort_to_error,
 	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_InitCallBackState,
 };
 
 /*
  * CB.InitCallBackState3 operation type
  */
+static CM_NAME(InitCallBackState3);
 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
-	.name		= "CB.InitCallBackState3",
+	.name		= afs_SRXCBInitCallBackState3_name,
 	.deliver	= afs_deliver_cb_init_call_back_state3,
 	.abort_to_error	= afs_abort_to_error,
 	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_InitCallBackState,
 };
 
 /*
  * CB.Probe operation type
  */
+static CM_NAME(Probe);
 static const struct afs_call_type afs_SRXCBProbe = {
-	.name		= "CB.Probe",
+	.name		= afs_SRXCBProbe_name,
 	.deliver	= afs_deliver_cb_probe,
 	.abort_to_error	= afs_abort_to_error,
 	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_Probe,
 };
 
 /*
  * CB.ProbeUuid operation type
  */
+static CM_NAME(ProbeUuid);
 static const struct afs_call_type afs_SRXCBProbeUuid = {
-	.name		= "CB.ProbeUuid",
+	.name		= afs_SRXCBProbeUuid_name,
 	.deliver	= afs_deliver_cb_probe_uuid,
 	.abort_to_error	= afs_abort_to_error,
 	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_ProbeUuid,
 };
 
 /*
  * CB.TellMeAboutYourself operation type
  */
+static CM_NAME(TellMeAboutYourself);
 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
-	.name		= "CB.TellMeAboutYourself",
+	.name		= afs_SRXCBTellMeAboutYourself_name,
 	.deliver	= afs_deliver_cb_tell_me_about_yourself,
 	.abort_to_error	= afs_abort_to_error,
 	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_TellMeAboutYourself,
 };
 
 /*
@@ -153,6 +174,7 @@ static void SRXAFSCB_CallBack(struct work_struct *work)
 	afs_send_empty_reply(call);
 
 	afs_break_callbacks(call->server, call->count, call->request);
+	afs_put_call(call);
 	_leave("");
 }
 
@@ -274,9 +296,7 @@ static int afs_deliver_cb_callback(struct afs_call *call)
 		return -ENOTCONN;
 	call->server = server;
 
-	INIT_WORK(&call->work, SRXAFSCB_CallBack);
-	queue_work(afs_wq, &call->work);
-	return 0;
+	return afs_queue_call_work(call);
 }
 
 /*
@@ -290,6 +310,7 @@ static void SRXAFSCB_InitCallBackState(struct work_struct *work)
 
 	afs_init_callback_state(call->server);
 	afs_send_empty_reply(call);
+	afs_put_call(call);
 	_leave("");
 }
 
@@ -320,9 +341,7 @@ static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
 		return -ENOTCONN;
 	call->server = server;
 
-	INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
-	queue_work(afs_wq, &call->work);
-	return 0;
+	return afs_queue_call_work(call);
 }
 
 /*
@@ -394,9 +413,7 @@ static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
 		return -ENOTCONN;
 	call->server = server;
 
-	INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
-	queue_work(afs_wq, &call->work);
-	return 0;
+	return afs_queue_call_work(call);
 }
 
 /*
@@ -408,6 +425,7 @@ static void SRXAFSCB_Probe(struct work_struct *work)
 
 	_enter("");
 	afs_send_empty_reply(call);
+	afs_put_call(call);
 	_leave("");
 }
 
@@ -427,9 +445,7 @@ static int afs_deliver_cb_probe(struct afs_call *call)
 	/* no unmarshalling required */
 	call->state = AFS_CALL_REPLYING;
 
-	INIT_WORK(&call->work, SRXAFSCB_Probe);
-	queue_work(afs_wq, &call->work);
-	return 0;
+	return afs_queue_call_work(call);
 }
 
 /*
@@ -452,6 +468,7 @@ static void SRXAFSCB_ProbeUuid(struct work_struct *work)
 		reply.match = htonl(1);
 
 	afs_send_simple_reply(call, &reply, sizeof(reply));
+	afs_put_call(call);
 	_leave("");
 }
 
@@ -510,9 +527,7 @@ static int afs_deliver_cb_probe_uuid(struct afs_call *call)
 
 	call->state = AFS_CALL_REPLYING;
 
-	INIT_WORK(&call->work, SRXAFSCB_ProbeUuid);
-	queue_work(afs_wq, &call->work);
-	return 0;
+	return afs_queue_call_work(call);
 }
 
 /*
@@ -574,7 +589,7 @@ static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
 	reply.cap.capcount = htonl(1);
 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
 	afs_send_simple_reply(call, &reply, sizeof(reply));
-
+	afs_put_call(call);
 	_leave("");
 }
 
@@ -594,7 +609,5 @@ static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
 	/* no unmarshalling required */
 	call->state = AFS_CALL_REPLYING;
 
-	INIT_WORK(&call->work, SRXAFSCB_TellMeAboutYourself);
-	queue_work(afs_wq, &call->work);
-	return 0;
+	return afs_queue_call_work(call);
 }