aboutsummaryrefslogtreecommitdiffstats
path: root/net/sunrpc/xprtrdma/svc_rdma_rw.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/sunrpc/xprtrdma/svc_rdma_rw.c')
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma_rw.c58
1 files changed, 39 insertions, 19 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c
index 7d4faf309601..04ec2a83af69 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_rw.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c
@@ -480,18 +480,19 @@ static int svc_rdma_send_xdr_kvec(struct svc_rdma_write_info *info,
vec->iov_len);
}
-/* Send an xdr_buf's page list by itself. A Write chunk is
- * just the page list. a Reply chunk is the head, page list,
- * and tail. This function is shared between the two types
- * of chunk.
+/* 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.
*/
static int svc_rdma_send_xdr_pagelist(struct svc_rdma_write_info *info,
- struct xdr_buf *xdr)
+ struct xdr_buf *xdr,
+ unsigned int offset,
+ unsigned long length)
{
info->wi_xdr = xdr;
- info->wi_next_off = 0;
+ info->wi_next_off = offset - xdr->head[0].iov_len;
return svc_rdma_build_writes(info, svc_rdma_pagelist_to_sg,
- xdr->page_len);
+ length);
}
/**
@@ -499,6 +500,8 @@ static int svc_rdma_send_xdr_pagelist(struct svc_rdma_write_info *info,
* @rdma: controlling RDMA transport
* @wr_ch: Write chunk provided by client
* @xdr: xdr_buf containing the data payload
+ * @offset: payload's byte offset in @xdr
+ * @length: size of payload, in bytes
*
* Returns a non-negative number of bytes the chunk consumed, or
* %-E2BIG if the payload was larger than the Write chunk,
@@ -508,19 +511,20 @@ static int svc_rdma_send_xdr_pagelist(struct svc_rdma_write_info *info,
* %-EIO if rdma_rw initialization failed (DMA mapping, etc).
*/
int svc_rdma_send_write_chunk(struct svcxprt_rdma *rdma, __be32 *wr_ch,
- struct xdr_buf *xdr)
+ struct xdr_buf *xdr,
+ unsigned int offset, unsigned long length)
{
struct svc_rdma_write_info *info;
int ret;
- if (!xdr->page_len)
+ if (!length)
return 0;
info = svc_rdma_write_info_alloc(rdma, wr_ch);
if (!info)
return -ENOMEM;
- ret = svc_rdma_send_xdr_pagelist(info, xdr);
+ ret = svc_rdma_send_xdr_pagelist(info, xdr, offset, length);
if (ret < 0)
goto out_err;
@@ -529,7 +533,7 @@ int svc_rdma_send_write_chunk(struct svcxprt_rdma *rdma, __be32 *wr_ch,
goto out_err;
trace_svcrdma_encode_write(xdr->page_len);
- return xdr->page_len;
+ return length;
out_err:
svc_rdma_write_info_free(info);
@@ -569,7 +573,9 @@ int svc_rdma_send_reply_chunk(struct svcxprt_rdma *rdma, __be32 *rp_ch,
* client did not provide Write chunks.
*/
if (!writelist && xdr->page_len) {
- ret = svc_rdma_send_xdr_pagelist(info, xdr);
+ ret = svc_rdma_send_xdr_pagelist(info, xdr,
+ xdr->head[0].iov_len,
+ xdr->page_len);
if (ret < 0)
goto out_err;
consumed += xdr->page_len;
@@ -670,7 +676,6 @@ static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp,
struct svc_rdma_read_info *info,
__be32 *p)
{
- unsigned int i;
int ret;
ret = -EINVAL;
@@ -693,12 +698,6 @@ static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp,
info->ri_chunklen += rs_length;
}
- /* Pages under I/O have been copied to head->rc_pages.
- * Prevent their premature release by svc_xprt_release() .
- */
- for (i = 0; i < info->ri_readctxt->rc_page_count; i++)
- rqstp->rq_pages[i] = NULL;
-
return ret;
}
@@ -793,6 +792,26 @@ out:
return ret;
}
+/* Pages under I/O have been copied to head->rc_pages. Ensure they
+ * are not released by svc_xprt_release() until the I/O is complete.
+ *
+ * This has to be done after all Read WRs are constructed to properly
+ * handle a page that is part of I/O on behalf of two different RDMA
+ * segments.
+ *
+ * Do this only if I/O has been posted. Otherwise, we do indeed want
+ * svc_xprt_release() to clean things up properly.
+ */
+static void svc_rdma_save_io_pages(struct svc_rqst *rqstp,
+ const unsigned int start,
+ const unsigned int num_pages)
+{
+ unsigned int i;
+
+ for (i = start; i < num_pages + start; i++)
+ rqstp->rq_pages[i] = NULL;
+}
+
/**
* svc_rdma_recv_read_chunk - Pull a Read chunk from the client
* @rdma: controlling RDMA transport
@@ -846,6 +865,7 @@ int svc_rdma_recv_read_chunk(struct svcxprt_rdma *rdma, struct svc_rqst *rqstp,
ret = svc_rdma_post_chunk_ctxt(&info->ri_cc);
if (ret < 0)
goto out_err;
+ svc_rdma_save_io_pages(rqstp, 0, head->rc_page_count);
return 0;
out_err: