svcrdma: Move read list XDR round-up logic

This is a pre-requisite for a subsequent patch.

Read list XDR round-up needs to be done _before_ additional inline
content is copied to the end of the XDR buffer's page list. Move
the logic added by commit e560e3b510d2 ("svcrdma: Add zero padding
if the client doesn't send it").

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 9 insertions, 28 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index 36cf51a3eab7..a345cadad4dd 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -43,7 +43,6 @@
 #include <linux/sunrpc/debug.h>
 #include <linux/sunrpc/rpc_rdma.h>
 #include <linux/spinlock.h>
-#include <linux/highmem.h>
 #include <asm/unaligned.h>
 #include <rdma/ib_verbs.h>
 #include <rdma/rdma_cm.h>
@@ -434,6 +433,15 @@ static int rdma_read_chunks(struct svcxprt_rdma *xprt,
                 }
         }
 
+        /* Read list may need XDR round-up (see RFC 5666, s. 3.7) */
+        if (page_offset & 3) {
+                u32 pad = 4 - (page_offset & 3);
+
+                head->arg.page_len += pad;
+                head->arg.len += pad;
+                head->arg.buflen += pad;
+        }
+
         ret = 1;
         head->position = position;
 
@@ -446,32 +454,6 @@ static int rdma_read_chunks(struct svcxprt_rdma *xprt,
         return ret;
 }
 
-/*
- * To avoid a separate RDMA READ just for a handful of zero bytes,
- * RFC 5666 section 3.7 allows the client to omit the XDR zero pad
- * in chunk lists.
- */
-static void
-rdma_fix_xdr_pad(struct xdr_buf *buf)
-{
-        unsigned int page_len = buf->page_len;
-        unsigned int size = (XDR_QUADLEN(page_len) << 2) - page_len;
-        unsigned int offset, pg_no;
-        char *p;
-
-        if (size == 0)
-                return;
-
-        pg_no = page_len >> PAGE_SHIFT;
-        offset = page_len & ~PAGE_MASK;
-        p = page_address(buf->pages[pg_no]);
-        memset(p + offset, 0, size);
-
-        buf->page_len += size;
-        buf->buflen += size;
-        buf->len += size;
-}
-
 static int rdma_read_complete(struct svc_rqst *rqstp,
                               struct svc_rdma_op_ctxt *head)
 {
@@ -499,7 +481,6 @@ static int rdma_read_complete(struct svc_rqst *rqstp,
         }
 
         /* Point rq_arg.pages past header */
-        rdma_fix_xdr_pad(&head->arg);
         rqstp->rq_arg.pages = &rqstp->rq_pages[head->hdr_count];
         rqstp->rq_arg.page_len = head->arg.page_len;
         rqstp->rq_arg.page_base = head->arg.page_base;