[pnfs] [PATCH 3/8] Added a function to read the call/reply flag

[iyer at netapp.com]

From: Rahul Iyer <iyer at netapp.com>

Added a function xs_tcp_read_calldir() to read in the call/reply flag and store
it in xprt->tcp_calldir.

Signed-off-by: Rahul Iyer <iyer at netapp.com>
---
 net/sunrpc/xprtsock.c |   28 ++++++++++++++++++++++++++++
 1 files changed, 28 insertions(+), 0 deletions(-)

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 441bd53..ab1e8fb 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -648,6 +648,34 @@ static inline void xs_tcp_read_xid(struct rpc_xprt *xprt, skb_reader_t *desc)
 	xs_tcp_check_recm(xprt);
 }
 
+static inline void xs_tcp_read_calldir(struct rpc_xprt *xprt, skb_reader_t *desc)
+{
+	size_t len, used;
+	u32 offset;
+	char *p;
+
+	/* The reason for this rather odd calculation is that we want
+	 * xprt->tcp_offset to be 8 at the end of this routine (4 bytes for the
+	 * xid and 4 bytes for the call/reply flag). When coming into this
+	 * function for the first time, xprt->tcp_offset is 4 (after reading
+	 * the xid).
+	 */
+	offset = xprt->tcp_offset - sizeof(xprt->tcp_xid);
+	len = sizeof(xprt->tcp_calldir) - offset;
+	dprintk("RPC:      reading CALL/REPLY flag (%Zu bytes)\n", len);
+	p = ((char *) &xprt->tcp_calldir) + offset;
+	used = xs_tcp_copy_data(desc, p, len);
+	xprt->tcp_offset += used;
+	if (used != len)
+		return;
+	xprt->tcp_flags &= ~XPRT_COPY_CALLDIR;
+	xprt->tcp_flags |= XPRT_COPY_DATA;
+	xprt->tcp_copied += 4;
+	dprintk("RPC:      reading reply for CALL/REPLY flag %08x\n",
+						ntohl(xprt->tcp_xid));
+	xs_tcp_check_recm(xprt);
+}
+
 static inline void xs_tcp_read_request(struct rpc_xprt *xprt, skb_reader_t *desc)
 {
 	struct rpc_rqst *req;
-- 
1.5.0.2