xdr_start() can return the wrong rmsgp address if an assumption about how the xdr_buf was constructed changes. When it gets it wrong, the client receives a reply that has gibberish in the RPC/RDMA header, preventing it from matching a waiting RPC request.
Instead, make (and document) just one assumption: that the RDMA header for the client's RPC call is at the start of the first page in rq_pages. Signed-off-by: Chuck Lever <[email protected]> --- net/sunrpc/xprtrdma/svc_rdma_sendto.c | 18 ++++-------------- 1 files changed, 4 insertions(+), 14 deletions(-) diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c index 7d79897..7de33d1 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c +++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c @@ -483,18 +483,6 @@ void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp) { } -/* - * Return the start of an xdr buffer. - */ -static void *xdr_start(struct xdr_buf *xdr) -{ - return xdr->head[0].iov_base - - (xdr->len - - xdr->page_len - - xdr->tail[0].iov_len - - xdr->head[0].iov_len); -} - int svc_rdma_sendto(struct svc_rqst *rqstp) { struct svc_xprt *xprt = rqstp->rq_xprt; @@ -512,8 +500,10 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) dprintk("svcrdma: sending response for rqstp=%p\n", rqstp); - /* Get the RDMA request header. */ - rdma_argp = xdr_start(&rqstp->rq_arg); + /* Get the RDMA request header. The receive logic always + * places this at the start of page 0. + */ + rdma_argp = page_address(rqstp->rq_pages[0]); /* Build an req vec for the XDR */ ctxt = svc_rdma_get_context(rdma); -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
