svcrdma: Fix dma map direction for rdma read targets

The nfs server rdma transport was mapping rdma read target pages for
TO_DEVICE instead of FROM_DEVICE.  This causes data corruption on non
cache-coherent systems if frmrs are used.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index 629a287..42a6f9f 100644 (file)
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -265,7 +265,7 @@ static int fast_reg_read_chunks(struct svcxprt_rdma *xprt,
                frmr->page_list->page_list[page_no] =
                        ib_dma_map_single(xprt->sc_cm_id->device,
                                          page_address(rqstp->rq_arg.pages[page_no]),
-                                         PAGE_SIZE, DMA_TO_DEVICE);
+                                         PAGE_SIZE, DMA_FROM_DEVICE);
                if (ib_dma_mapping_error(xprt->sc_cm_id->device,
                                         frmr->page_list->page_list[page_no]))
                        goto fatal_err;