From f4a2e418bfd03a1f25f515e8a92ecd584d96cfc1 Mon Sep 17 00:00:00 2001 From: Ricardo Labiaga Date: Wed, 1 Apr 2009 09:22:54 -0400 Subject: [PATCH] nfs41: Process the RPC call direction 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. [was nfs41: Skip past the RPC call direction] Signed-off-by: Ricardo Labiaga Signed-off-by: Benny Halevy [nfs41: sunrpc: Add RPC direction back into the XDR buffer] Signed-off-by: Ricardo Labiaga Signed-off-by: Benny Halevy [nfs41: sunrpc: Don't skip past the RPC call direction] Signed-off-by: Ricardo Labiaga Signed-off-by: Benny Halevy --- net/sunrpc/clnt.c | 5 +++-- net/sunrpc/xprtsock.c | 31 +++++++++++++++++++++++++------ 2 files changed, 28 insertions(+), 8 deletions(-) diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index d00e8135f866..aca3ab6fc140 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -1390,13 +1390,14 @@ rpc_verify_header(struct rpc_task *task) } if ((len -= 3) < 0) goto out_overflow; - p += 1; /* skip XID */ + p += 1; /* skip XID */ if ((n = ntohl(*p++)) != RPC_REPLY) { dprintk("RPC: %5u %s: not an RPC reply: %x\n", - task->tk_pid, __func__, n); + task->tk_pid, __func__, n); goto out_garbage; } + if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { if (--len < 0) goto out_overflow; diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 8975c10591c3..a48df1449ece 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -270,12 +270,13 @@ 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) { @@ -997,7 +998,7 @@ 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" @@ -1026,9 +1027,13 @@ 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 @@ -1059,6 +1064,20 @@ static inline void xs_tcp_read_request(struct rpc_xprt *xprt, struct xdr_skb_rea } 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; @@ -1156,7 +1175,7 @@ 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; } -- 2.20.1