From: Ricardo Labiaga Subject: [PATCH 09/14] SQUASHME: nfs41: sunrpc: Add RPC direction back into the XDR buffer Date: Thu, 11 Jun 2009 22:54:15 -0700 Message-ID: <1244786060-2200-10-git-send-email-Ricardo.Labiaga@netapp.com> References: <> <1244786060-2200-1-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-2-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-3-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-4-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-5-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-6-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-7-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-8-git-send-email-Ricardo.Labiaga@netapp.com> <1244786060-2200-9-git-send-email-Ricardo.Labiaga@netapp.com> Cc: bhalevy@panasas.com, pnfs@linux-nfs.org, linux-nfs@vger.kernel.org, Ricardo Labiaga To: trond.myklebust@netapp.com Return-path: Received: from mx2.netapp.com ([216.240.18.37]:2056 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753276AbZFLF6L (ORCPT ); Fri, 12 Jun 2009 01:58:11 -0400 In-Reply-To: <1244786060-2200-9-git-send-email-Ricardo.Labiaga@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: [squash with: nfs41: Skip past the RPC call direction] An earlier nfs41/sunrpc patch incorrectly assumed that all transports will read the RPC direction and route callbacks or replies to the processing routines. This is only currently implemented for TCP, so rpc_verify_header() needs to continue verifying that it is processing an RPC_REPLY. Reading and storing the RPC direction is a three step process. 1. xs_tcp_read_calldir() reads the RPC direction, but it will not store it in the XDR buffer since the 'struct rpc_rqst' is not yet available. 2. The 'struct rpc_rqst' is obtained during the TCP_RCV_COPY_DATA state. This state need not necessarily be preceeded by the TCP_RCV_READ_CALLDIR. For example, we may be reading a continuation packet to a large reply. Therefore, we can't simply obtain the 'struct rpc_rqst' during the TCP_RCV_READ_CALLDIR state and assume it's available during TCP_RCV_COPY_DATA. This patch adds a new TCP_RCV_READ_CALLDIR flag to indicate the need to read the RPC direction. It then uses TCP_RCV_COPY_CALLDIR to indicate the RPC direction needs to be saved after the 'struct rpc_rqst' has been allocated. 3. The 'struct rpc_rqst' is obtained by the xs_tcp_read_data() helper functions. xs_tcp_read_common() then saves the RPC direction in the XDR buffer if TCP_RCV_COPY_CALLDIR is set. This will happen when we're reading the data immediately after the direction was read. xs_tcp_read_common() then clears this flag. Signed-off-by: Ricardo Labiaga --- net/sunrpc/xprtsock.c | 31 +++++++++++++++++++++++++------ 1 files changed, 25 insertions(+), 6 deletions(-) diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 8ec2600..fe57ebd 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -275,12 +275,13 @@ struct sock_xprt { #define TCP_RCV_COPY_FRAGHDR (1UL << 1) #define TCP_RCV_COPY_XID (1UL << 2) #define TCP_RCV_COPY_DATA (1UL << 3) -#define TCP_RCV_COPY_CALLDIR (1UL << 4) +#define TCP_RCV_READ_CALLDIR (1UL << 4) +#define TCP_RCV_COPY_CALLDIR (1UL << 5) /* * TCP RPC flags */ -#define TCP_RPC_REPLY (1UL << 5) +#define TCP_RPC_REPLY (1UL << 6) static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt) { @@ -1002,7 +1003,7 @@ static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_r if (used != len) return; transport->tcp_flags &= ~TCP_RCV_COPY_XID; - transport->tcp_flags |= TCP_RCV_COPY_CALLDIR; + transport->tcp_flags |= TCP_RCV_READ_CALLDIR; transport->tcp_copied = 4; dprintk("RPC: reading %s XID %08x\n", (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for" @@ -1031,9 +1032,13 @@ static inline void xs_tcp_read_calldir(struct sock_xprt *transport, transport->tcp_offset += used; if (used != len) return; - transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR; + transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR; + transport->tcp_flags |= TCP_RCV_COPY_CALLDIR; transport->tcp_flags |= TCP_RCV_COPY_DATA; - transport->tcp_copied += 4; + /* + * We don't yet have the XDR buffer, so we will write the calldir + * out after we get the buffer from the 'struct rpc_rqst' + */ if (ntohl(calldir) == RPC_REPLY) transport->tcp_flags |= TCP_RPC_REPLY; else @@ -1055,6 +1060,20 @@ static inline void xs_tcp_read_common(struct rpc_xprt *xprt, ssize_t r; rcvbuf = &req->rq_private_buf; + + if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) { + /* + * Save the RPC direction in the XDR buffer + */ + __be32 calldir = transport->tcp_flags & TCP_RPC_REPLY ? + htonl(RPC_REPLY) : 0; + + memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied, + &calldir, sizeof(calldir)); + transport->tcp_copied += sizeof(calldir); + transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR; + } + len = desc->count; if (len > transport->tcp_reclen - transport->tcp_offset) { struct xdr_skb_reader my_desc; @@ -1258,7 +1277,7 @@ static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, uns continue; } /* Read in the call/reply flag */ - if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) { + if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) { xs_tcp_read_calldir(transport, &desc); continue; } -- 1.5.4.3