@@ -296,7 +296,6 @@ xprt_setup_rdma(struct xprt_create *args)
xprt->resvport = 0; /* privileged port not needed */
xprt->tsh_size = 0; /* RPC-RDMA handles framing */
- xprt->max_payload = RPCRDMA_MAX_DATA_SEGS * PAGE_SIZE;
xprt->ops = &xprt_rdma_procs;
/*
@@ -382,6 +381,9 @@ xprt_setup_rdma(struct xprt_create *args)
new_ep->rep_xprt = xprt;
xprt_rdma_format_addresses(xprt);
+ xprt->max_payload = rpcrdma_max_payload(new_xprt);
+ dprintk("RPC: %s: transport data payload maximum: %zu bytes\n",
+ __func__, xprt->max_payload);
if (!try_module_get(THIS_MODULE))
goto out4;
@@ -1819,3 +1819,44 @@ rpcrdma_ep_post_recv(struct rpcrdma_ia *ia,
rc);
return rc;
}
+
+/* Physical mapping means one Read/Write list entry per-page.
+ * All list entries must fit within an inline buffer
+ *
+ * NB: The server must return a Write list for NFS READ,
+ * which has the same constraint. Factor in the inline
+ * rsize as well.
+ */
+static size_t
+rpcrdma_physical_max_payload(struct rpcrdma_xprt *r_xprt)
+{
+ struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
+ unsigned int inline_size, pages;
+
+ inline_size = min_t(unsigned int,
+ cdata->inline_wsize, cdata->inline_rsize) -
+ RPCRDMA_HDRLEN_MIN;
+ pages = inline_size / sizeof(struct rpcrdma_segment);
+ return pages << PAGE_SHIFT;
+}
+
+static size_t
+rpcrdma_mr_max_payload(struct rpcrdma_xprt *r_xprt)
+{
+ return RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT;
+}
+
+size_t
+rpcrdma_max_payload(struct rpcrdma_xprt *r_xprt)
+{
+ size_t result;
+
+ switch (r_xprt->rx_ia.ri_memreg_strategy) {
+ case RPCRDMA_ALLPHYSICAL:
+ result = rpcrdma_physical_max_payload(r_xprt);
+ break;
+ default:
+ result = rpcrdma_mr_max_payload(r_xprt);
+ }
+ return result;
+}
@@ -348,6 +348,7 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *);
* RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
*/
int rpcrdma_marshal_req(struct rpc_rqst *);
+size_t rpcrdma_max_payload(struct rpcrdma_xprt *);
/* Temporary NFS request map cache. Created in svc_rdma.c */
extern struct kmem_cache *svc_rdma_map_cachep;
When the client uses physical memory registration, each page in the payload gets its own array entry in the RPC/RDMA header's chunk list. Therefore, don't advertise a maximum payload size that would require more array entries than can fit in the RPC buffer where RPC/RDMA headers are built. BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=248 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> --- net/sunrpc/xprtrdma/transport.c | 4 +++- net/sunrpc/xprtrdma/verbs.c | 41 +++++++++++++++++++++++++++++++++++++++ net/sunrpc/xprtrdma/xprt_rdma.h | 1 + 3 files changed, 45 insertions(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html