afs: Implement the YFS cache manager service

Implement the YFS cache manager service which gives extra capabilities on
top of AFS.  This is done by listening for an additional service on the
same port and indicating that anyone requesting an upgrade should be
upgraded to the YFS port.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 102 insertions, 1 deletions

diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
index fc0010d800a0..8cf8d10daa6c 100644
--- a/fs/afs/cmservice.c
+++ b/fs/afs/cmservice.c
@@ -16,6 +16,7 @@
 #include <linux/ip.h>
 #include "internal.h"
 #include "afs_cm.h"
+#include "protocol_yfs.h"
 
 static int afs_deliver_cb_init_call_back_state(struct afs_call *);
 static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
@@ -30,6 +31,8 @@ static void SRXAFSCB_Probe(struct work_struct *);
 static void SRXAFSCB_ProbeUuid(struct work_struct *);
 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
 
+static int afs_deliver_yfs_cb_callback(struct afs_call *);
+
 #define CM_NAME(name) \
 	const char afs_SRXCB##name##_name[] __tracepoint_string =	\
 		"CB." #name
@@ -101,12 +104,23 @@ static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
 };
 
 /*
+ * YFS CB.CallBack operation type
+ */
+static CM_NAME(YFS_CallBack);
+static const struct afs_call_type afs_SRXYFSCB_CallBack = {
+	.name		= afs_SRXCBYFS_CallBack_name,
+	.deliver	= afs_deliver_yfs_cb_callback,
+	.destructor	= afs_cm_destructor,
+	.work		= SRXAFSCB_CallBack,
+};
+
+/*
  * route an incoming cache manager call
  * - return T if supported, F if not
  */
 bool afs_cm_incoming_call(struct afs_call *call)
 {
-	_enter("{CB.OP %u}", call->operation_ID);
+	_enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);
 
 	switch (call->operation_ID) {
 	case CBCallBack:
@@ -127,6 +141,11 @@ bool afs_cm_incoming_call(struct afs_call *call)
 	case CBTellMeAboutYourself:
 		call->type = &afs_SRXCBTellMeAboutYourself;
 		return true;
+	case YFSCBCallBack:
+		if (call->service_id != YFS_CM_SERVICE)
+			return false;
+		call->type = &afs_SRXYFSCB_CallBack;
+		return true;
 	default:
 		return false;
 	}
@@ -570,3 +589,85 @@ static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
 
 	return afs_queue_call_work(call);
 }
+
+/*
+ * deliver request data to a YFS CB.CallBack call
+ */
+static int afs_deliver_yfs_cb_callback(struct afs_call *call)
+{
+	struct afs_callback_break *cb;
+	struct sockaddr_rxrpc srx;
+	struct yfs_xdr_YFSFid *bp;
+	size_t size;
+	int ret, loop;
+
+	_enter("{%u}", call->unmarshall);
+
+	switch (call->unmarshall) {
+	case 0:
+		afs_extract_to_tmp(call);
+		call->unmarshall++;
+
+		/* extract the FID array and its count in two steps */
+	case 1:
+		_debug("extract FID count");
+		ret = afs_extract_data(call, true);
+		if (ret < 0)
+			return ret;
+
+		call->count = ntohl(call->tmp);
+		_debug("FID count: %u", call->count);
+		if (call->count > YFSCBMAX)
+			return afs_protocol_error(call, -EBADMSG,
+						  afs_eproto_cb_fid_count);
+
+		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
+		call->buffer = kmalloc(size, GFP_KERNEL);
+		if (!call->buffer)
+			return -ENOMEM;
+		afs_extract_to_buf(call, size);
+		call->unmarshall++;
+
+	case 2:
+		_debug("extract FID array");
+		ret = afs_extract_data(call, false);
+		if (ret < 0)
+			return ret;
+
+		_debug("unmarshall FID array");
+		call->request = kcalloc(call->count,
+					sizeof(struct afs_callback_break),
+					GFP_KERNEL);
+		if (!call->request)
+			return -ENOMEM;
+
+		cb = call->request;
+		bp = call->buffer;
+		for (loop = call->count; loop > 0; loop--, cb++) {
+			cb->fid.vid	= xdr_to_u64(bp->volume);
+			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
+			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
+			cb->fid.unique	= ntohl(bp->vnode.unique);
+			bp++;
+		}
+
+		afs_extract_to_tmp(call);
+		call->unmarshall++;
+
+	case 3:
+		break;
+	}
+
+	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
+		return afs_io_error(call, afs_io_error_cm_reply);
+
+	/* We'll need the file server record as that tells us which set of
+	 * vnodes to operate upon.
+	 */
+	rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
+	call->cm_server = afs_find_server(call->net, &srx);
+	if (!call->cm_server)
+		trace_afs_cm_no_server(call, &srx);
+
+	return afs_queue_call_work(call);
+}