diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 93 |
1 files changed, 92 insertions, 1 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index 2de947183a7a..034bdd02f925 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -767,10 +767,86 @@ static bool svc_rdma_is_reverse_direction_reply(struct svc_xprt *xprt, return true; } +/* Finish constructing the RPC Call message in rqstp::rq_arg. + * + * The incoming RPC/RDMA message is an RDMA_MSG type message + * with a single Read chunk (only the upper layer data payload + * was conveyed via RDMA Read). + */ +static void svc_rdma_read_complete_one(struct svc_rqst *rqstp, + struct svc_rdma_recv_ctxt *ctxt) +{ + struct svc_rdma_chunk *chunk = pcl_first_chunk(&ctxt->rc_read_pcl); + struct xdr_buf *buf = &rqstp->rq_arg; + unsigned int length; + + /* Split the Receive buffer between the head and tail + * buffers at Read chunk's position. XDR roundup of the + * chunk is not included in either the pagelist or in + * the tail. + */ + buf->tail[0].iov_base = buf->head[0].iov_base + chunk->ch_position; + buf->tail[0].iov_len = buf->head[0].iov_len - chunk->ch_position; + buf->head[0].iov_len = chunk->ch_position; + + /* Read chunk may need XDR roundup (see RFC 8166, s. 3.4.5.2). + * + * If the client already rounded up the chunk length, the + * length does not change. Otherwise, the length of the page + * list is increased to include XDR round-up. + * + * Currently these chunks always start at page offset 0, + * thus the rounded-up length never crosses a page boundary. + */ + buf->pages = &rqstp->rq_pages[0]; + length = xdr_align_size(chunk->ch_length); + buf->page_len = length; + buf->len += length; + buf->buflen += length; +} + +/* Finish constructing the RPC Call message in rqstp::rq_arg. + * + * The incoming RPC/RDMA message is an RDMA_MSG type message + * with payload in multiple Read chunks and no PZRC. + */ +static void svc_rdma_read_complete_multiple(struct svc_rqst *rqstp, + struct svc_rdma_recv_ctxt *ctxt) +{ + struct xdr_buf *buf = &rqstp->rq_arg; + + buf->len += ctxt->rc_readbytes; + buf->buflen += ctxt->rc_readbytes; + + buf->head[0].iov_base = page_address(rqstp->rq_pages[0]); + buf->head[0].iov_len = min_t(size_t, PAGE_SIZE, ctxt->rc_readbytes); + buf->pages = &rqstp->rq_pages[1]; + buf->page_len = ctxt->rc_readbytes - buf->head[0].iov_len; +} + +/* Finish constructing the RPC Call message in rqstp::rq_arg. + * + * The incoming RPC/RDMA message is an RDMA_NOMSG type message + * (the RPC message body was conveyed via RDMA Read). + */ +static void svc_rdma_read_complete_pzrc(struct svc_rqst *rqstp, + struct svc_rdma_recv_ctxt *ctxt) +{ + struct xdr_buf *buf = &rqstp->rq_arg; + + buf->len += ctxt->rc_readbytes; + buf->buflen += ctxt->rc_readbytes; + + buf->head[0].iov_base = page_address(rqstp->rq_pages[0]); + buf->head[0].iov_len = min_t(size_t, PAGE_SIZE, ctxt->rc_readbytes); + buf->pages = &rqstp->rq_pages[1]; + buf->page_len = ctxt->rc_readbytes - buf->head[0].iov_len; +} + static noinline void svc_rdma_read_complete(struct svc_rqst *rqstp, struct svc_rdma_recv_ctxt *ctxt) { - int i; + unsigned int i; /* Transfer the Read chunk pages into @rqstp.rq_pages, replacing * the rq_pages that were already allocated for this rqstp. @@ -789,6 +865,21 @@ static noinline void svc_rdma_read_complete(struct svc_rqst *rqstp, * pages in ctxt::rc_pages a second time. */ ctxt->rc_page_count = 0; + + /* Finish constructing the RPC Call message. The exact + * procedure for that depends on what kind of RPC/RDMA + * chunks were provided by the client. + */ + if (pcl_is_empty(&ctxt->rc_call_pcl)) { + if (ctxt->rc_read_pcl.cl_count == 1) + svc_rdma_read_complete_one(rqstp, ctxt); + else + svc_rdma_read_complete_multiple(rqstp, ctxt); + } else { + svc_rdma_read_complete_pzrc(rqstp, ctxt); + } + + trace_svcrdma_read_finished(&ctxt->rc_cid); } /** |