Refactor for subsequent changes.
Constify the xdr_buf argument to ensure the code here does not
modify it, and to enable callers to pass in a
"const struct xdr_buf *".
At the same time, rename the helper functions, which emit RDMA
Writes, not RDMA Sends, and add documenting comments.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
net/sunrpc/xprtrdma/svc_rdma_rw.c | 56 +++++++++++++++++++++++--------------
1 file changed, 35 insertions(+), 21 deletions(-)
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c
index d8b2e22c56c1..03c32b441d32 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_rw.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c
@@ -493,27 +493,42 @@ svc_rdma_build_writes(struct svc_rdma_write_info *info,
return -E2BIG;
}
-/* Send one of an xdr_buf's kvecs by itself. To send a Reply
- * chunk, the whole RPC Reply is written back to the client.
- * This function writes either the head or tail of the xdr_buf
- * containing the Reply.
+/**
+ * svc_rdma_iov_write - Construct RDMA Writes from an iov
+ * @info: pointer to write arguments
+ * @iov: kvec to write
+ *
+ * Returns:
+ * On succes, returns zero
+ * %-E2BIG if the client-provided Write chunk is too small
+ * %-ENOMEM if a resource has been exhausted
+ * %-EIO if an rdma-rw error occurred
*/
-static int svc_rdma_send_xdr_kvec(struct svc_rdma_write_info *info,
- struct kvec *vec)
+static int svc_rdma_iov_write(struct svc_rdma_write_info *info,
+ const struct kvec *iov)
{
- info->wi_base = vec->iov_base;
+ info->wi_base = iov->iov_base;
return svc_rdma_build_writes(info, svc_rdma_vec_to_sg,
- vec->iov_len);
+ iov->iov_len);
}
-/* Send an xdr_buf's page list by itself. A Write chunk is just
- * the page list. A Reply chunk is @xdr's head, page list, and
- * tail. This function is shared between the two types of chunk.
+/**
+ * svc_rdma_pages_write - Construct RDMA Writes from pages
+ * @info: pointer to write arguments
+ * @xdr: xdr_buf with pages to write
+ * @offset: offset into the content of @xdr
+ * @length: number of bytes to write
+ *
+ * Returns:
+ * On succes, returns zero
+ * %-E2BIG if the client-provided Write chunk is too small
+ * %-ENOMEM if a resource has been exhausted
+ * %-EIO if an rdma-rw error occurred
*/
-static int svc_rdma_send_xdr_pagelist(struct svc_rdma_write_info *info,
- struct xdr_buf *xdr,
- unsigned int offset,
- unsigned long length)
+static int svc_rdma_pages_write(struct svc_rdma_write_info *info,
+ const struct xdr_buf *xdr,
+ unsigned int offset,
+ unsigned long length)
{
info->wi_xdr = xdr;
info->wi_next_off = offset - xdr->head[0].iov_len;
@@ -550,7 +565,7 @@ int svc_rdma_send_write_chunk(struct svcxprt_rdma *rdma, __be32 *wr_ch,
if (!info)
return -ENOMEM;
- ret = svc_rdma_send_xdr_pagelist(info, xdr, offset, length);
+ ret = svc_rdma_pages_write(info, xdr, offset, length);
if (ret < 0)
goto out_err;
@@ -590,7 +605,7 @@ int svc_rdma_send_reply_chunk(struct svcxprt_rdma *rdma,
if (!info)
return -ENOMEM;
- ret = svc_rdma_send_xdr_kvec(info, &xdr->head[0]);
+ ret = svc_rdma_iov_write(info, &xdr->head[0]);
if (ret < 0)
goto out_err;
consumed = xdr->head[0].iov_len;
@@ -599,16 +614,15 @@ int svc_rdma_send_reply_chunk(struct svcxprt_rdma *rdma,
* client did not provide Write chunks.
*/
if (!rctxt->rc_write_list && xdr->page_len) {
- ret = svc_rdma_send_xdr_pagelist(info, xdr,
- xdr->head[0].iov_len,
- xdr->page_len);
+ ret = svc_rdma_pages_write(info, xdr, xdr->head[0].iov_len,
+ xdr->page_len);
if (ret < 0)
goto out_err;
consumed += xdr->page_len;
}
if (xdr->tail[0].iov_len) {
- ret = svc_rdma_send_xdr_kvec(info, &xdr->tail[0]);
+ ret = svc_rdma_iov_write(info, &xdr->tail[0]);
if (ret < 0)
goto out_err;
consumed += xdr->tail[0].iov_len;
