diff options
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index a345cadad4dd..f9f13a32ddb8 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -364,6 +364,56 @@ rdma_rcl_chunk_count(struct rpcrdma_read_chunk *ch) return count; } +/* If there was additional inline content, append it to the end of arg.pages. + * Tail copy has to be done after the reader function has determined how many + * pages are needed for RDMA READ. + */ +static int +rdma_copy_tail(struct svc_rqst *rqstp, struct svc_rdma_op_ctxt *head, + u32 position, u32 byte_count, u32 page_offset, int page_no) +{ + char *srcp, *destp; + int ret; + + ret = 0; + srcp = head->arg.head[0].iov_base + position; + byte_count = head->arg.head[0].iov_len - position; + if (byte_count > PAGE_SIZE) { + dprintk("svcrdma: large tail unsupported\n"); + return 0; + } + + /* Fit as much of the tail on the current page as possible */ + if (page_offset != PAGE_SIZE) { + destp = page_address(rqstp->rq_arg.pages[page_no]); + destp += page_offset; + while (byte_count--) { + *destp++ = *srcp++; + page_offset++; + if (page_offset == PAGE_SIZE && byte_count) + goto more; + } + goto done; + } + +more: + /* Fit the rest on the next page */ + page_no++; + destp = page_address(rqstp->rq_arg.pages[page_no]); + while (byte_count--) + *destp++ = *srcp++; + + rqstp->rq_respages = &rqstp->rq_arg.pages[page_no+1]; + rqstp->rq_next_page = rqstp->rq_respages + 1; + +done: + byte_count = head->arg.head[0].iov_len - position; + head->arg.page_len += byte_count; + head->arg.len += byte_count; + head->arg.buflen += byte_count; + return 1; +} + static int rdma_read_chunks(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, struct svc_rqst *rqstp, @@ -440,9 +490,14 @@ static int rdma_read_chunks(struct svcxprt_rdma *xprt, head->arg.page_len += pad; head->arg.len += pad; head->arg.buflen += pad; + page_offset += pad; } ret = 1; + if (position && position < head->arg.head[0].iov_len) + ret = rdma_copy_tail(rqstp, head, position, + byte_count, page_offset, page_no); + head->arg.head[0].iov_len = position; head->position = position; err: |