xprtrdma: Remove ALLPHYSICAL memory registration mode

No HCA or RNIC in the kernel tree requires the use of ALLPHYSICAL.

ALLPHYSICAL advertises in the clear on the network fabric an R_key
that is good for all of the client's memory. No known exploit
exists, but theoretically any user on the server can use that R_key
on the client's QP to read or update any part of the client's memory.

ALLPHYSICAL exposes the client to server bugs, including:
 o base/bounds errors causing data outside the i/o buffer to be
   accessed
 o RDMA access after reply causing data corruption and/or integrity
   fail

ALLPHYSICAL can't protect application memory regions from server
update after a local signal or soft timeout has terminated an RPC.

ALLPHYSICAL chunks are no larger than a page. Special cases to
handle small chunks and long chunk lists have been a source of
implementation complexity and bugs.

Signed-off-by: Chuck Lever <[email protected]>
Tested-by: Steve Wise <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>

Author: chucklever

net/sunrpc/xprtrdma/Makefile

@@ -1,7 +1,7 @@
 obj-$(CONFIG_SUNRPC_XPRT_RDMA) += rpcrdma.o
 
 rpcrdma-y := transport.o rpc_rdma.o verbs.o \
-	fmr_ops.o frwr_ops.o physical_ops.o \
+	fmr_ops.o frwr_ops.o \
 	svc_rdma.o svc_rdma_backchannel.o svc_rdma_transport.o \
 	svc_rdma_marshal.o svc_rdma_sendto.o svc_rdma_recvfrom.o \
 	module.o

net/sunrpc/xprtrdma/physical_ops.c

@@ -379,8 +379,6 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
 	struct rpcrdma_ia *ia = &xprt->rx_ia;
 	int rc;
 
-	ia->ri_dma_mr = NULL;
-
 	ia->ri_id = rpcrdma_create_id(xprt, ia, addr);
 	if (IS_ERR(ia->ri_id)) {
 		rc = PTR_ERR(ia->ri_id);
@@ -418,9 +416,6 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
 	case RPCRDMA_FRMR:
 		ia->ri_ops = &rpcrdma_frwr_memreg_ops;
 		break;
-	case RPCRDMA_ALLPHYSICAL:
-		ia->ri_ops = &rpcrdma_physical_memreg_ops;
-		break;
 	case RPCRDMA_MTHCAFMR:
 		ia->ri_ops = &rpcrdma_fmr_memreg_ops;
 		break;
@@ -585,8 +580,6 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
 out2:
 	ib_free_cq(sendcq);
 out1:
-	if (ia->ri_dma_mr)
-		ib_dereg_mr(ia->ri_dma_mr);
 	return rc;
 }
 
@@ -600,8 +593,6 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
 void
 rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
 {
-	int rc;
-
 	dprintk("RPC:       %s: entering, connected is %d\n",
 		__func__, ep->rep_connected);
 
@@ -615,12 +606,6 @@ rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
 
 	ib_free_cq(ep->rep_attr.recv_cq);
 	ib_free_cq(ep->rep_attr.send_cq);
-
-	if (ia->ri_dma_mr) {
-		rc = ib_dereg_mr(ia->ri_dma_mr);
-		dprintk("RPC:       %s: ib_dereg_mr returned %i\n",
-			__func__, rc);
-	}
 }
 
 /*

net/sunrpc/xprtrdma/verbs.c

@@ -68,7 +68,6 @@ struct rpcrdma_ia {
 	struct ib_device	*ri_device;
 	struct rdma_cm_id 	*ri_id;
 	struct ib_pd		*ri_pd;
-	struct ib_mr		*ri_dma_mr;
 	struct completion	ri_done;
 	int			ri_async_rc;
 	unsigned int		ri_max_frmr_depth;
@@ -269,8 +268,7 @@ struct rpcrdma_mw {
  * NOTES:
  *   o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we
  *     marshal. The number needed varies depending on the iov lists that
- *     are passed to us, the memory registration mode we are in, and if
- *     physical addressing is used, the layout.
+ *     are passed to us and the memory registration mode we are in.
  */
 
 struct rpcrdma_mr_seg {		/* chunk descriptors */
@@ -417,7 +415,6 @@ struct rpcrdma_memreg_ops {
 
 extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops;
 extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops;
-extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops;
 
 /*
  * RPCRDMA transport -- encapsulates the structures above for