SUNRPC xprtrdma: fix XDR tail buf marshalling for all ops

rpcrdma_convert_iovs is passed an xdr_buf representing either an RPC
request or an RPC reply. In the case of a request, several
calculations and tests involving pos are unnecessary. In the case of a
reply, several calculations and tests involving pos are incorrect (the
code tests pos against the reply xdr buf's len field, which is always
0 at the time rpcrdma_convert_iovs is executed). This change removes
the incorrect/unnecessary calculations and tests involving pos.

This fixes an observed problem when reading certain file sizes over
NFS/RDMA.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: Tom Talpey <talpey@netapp.com>
Signed-off-by: James Lentini <jlentini@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 1 insertions, 8 deletions

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index 9e11ce715958..ee8de7af2a5b 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -92,7 +92,6 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, int pos,
                 seg[n].mr_page = NULL;
                 seg[n].mr_offset = xdrbuf->head[0].iov_base;
                 seg[n].mr_len = xdrbuf->head[0].iov_len;
-                pos += xdrbuf->head[0].iov_len;
                 ++n;
         }
 
@@ -104,7 +103,6 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, int pos,
                 seg[n].mr_len = min_t(u32,
                         PAGE_SIZE - xdrbuf->page_base, xdrbuf->page_len);
                 len = xdrbuf->page_len - seg[n].mr_len;
-                pos += len;
                 ++n;
                 p = 1;
                 while (len > 0) {
@@ -119,20 +117,15 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, int pos,
                 }
         }
 
-        if (pos < xdrbuf->len && xdrbuf->tail[0].iov_len) {
+        if (xdrbuf->tail[0].iov_len) {
                 if (n == nsegs)
                         return 0;
                 seg[n].mr_page = NULL;
                 seg[n].mr_offset = xdrbuf->tail[0].iov_base;
                 seg[n].mr_len = xdrbuf->tail[0].iov_len;
-                pos += xdrbuf->tail[0].iov_len;
                 ++n;
         }
 
-        if (pos < xdrbuf->len)
-                dprintk("RPC:       %s: marshaled only %d of %d\n",
-                                __func__, pos, xdrbuf->len);
-
         return n;
 }