summaryrefslogtreecommitdiffstats
path: root/net/sunrpc/xprtrdma/verbs.c
diff options
context:
space:
mode:
authorChuck Lever2017-02-08 23:00:02 +0100
committerAnna Schumaker2017-02-10 20:02:36 +0100
commitc95a3c6b88658bcb8f77f85f31a0b9d9036e8016 (patch)
tree95431ad1a6ee327d27a59b13cb7407f1d1269c7d /net/sunrpc/xprtrdma/verbs.c
parentxprtrdma: Per-connection pad optimization (diff)
downloadkernel-qcow2-linux-c95a3c6b88658bcb8f77f85f31a0b9d9036e8016.tar.gz
kernel-qcow2-linux-c95a3c6b88658bcb8f77f85f31a0b9d9036e8016.tar.xz
kernel-qcow2-linux-c95a3c6b88658bcb8f77f85f31a0b9d9036e8016.zip
xprtrdma: Disable pad optimization by default
Commit d5440e27d3e5 ("xprtrdma: Enable pad optimization") made the Linux client omit XDR round-up padding in normal Read and Write chunks so that the client doesn't have to register and invalidate 3-byte memory regions that contain no real data. Unfortunately, my cheery 2014 assessment that this optimization "is supported now by both Linux and Solaris servers" was premature. We've found bugs in Solaris in this area since commit d5440e27d3e5 ("xprtrdma: Enable pad optimization") was merged (SYMLINK is the main offender). So for maximum interoperability, I'm disabling this optimization again. If a CM private message is exchanged when connecting, the client recognizes that the server is Linux, and enables the optimization for that connection. Until now the Solaris server bugs did not impact common operations, and were thus largely benign. Soon, less capable devices on Linux NFS/RDMA clients will make use of Read chunks more often, and these Solaris bugs will prevent interoperation in more cases. Fixes: 677eb17e94ed ("xprtrdma: Fix XDR tail buffer marshalling") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'net/sunrpc/xprtrdma/verbs.c')
-rw-r--r--net/sunrpc/xprtrdma/verbs.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 2a6a367a2dac..23f4da419a64 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -216,6 +216,7 @@ rpcrdma_update_connect_private(struct rpcrdma_xprt *r_xprt,
pmsg->cp_magic == rpcrdma_cmp_magic &&
pmsg->cp_version == RPCRDMA_CMP_VERSION) {
r_xprt->rx_ia.ri_reminv_expected = true;
+ r_xprt->rx_ia.ri_implicit_roundup = true;
rsize = rpcrdma_decode_buffer_size(pmsg->cp_send_size);
wsize = rpcrdma_decode_buffer_size(pmsg->cp_recv_size);
}