Server/client agnostic API changes to support padding xdr_buf::pages
automatically.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
include/linux/sunrpc/xdr.h | 74 ++++++++++++++++++++++++++++++++++----------
net/sunrpc/svc.c | 2 +
net/sunrpc/svc_xprt.c | 14 +++++---
3 files changed, 67 insertions(+), 23 deletions(-)
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index b41f34977995..47f55aad5a1e 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -24,6 +24,34 @@
*/
#define XDR_QUADLEN(l) (((l) + 3) >> 2)
+/**
+ * xdr_align_size - Calculate padded size of an object
+ * @n: Size of an object being XDR encoded (in bytes)
+ *
+ * Return value:
+ * Size (in bytes) of the object including xdr padding
+ */
+static inline size_t
+xdr_align_size(size_t n)
+{
+ const size_t mask = sizeof(__u32) - 1;
+
+ return (n + mask) & ~mask;
+}
+
+/**
+ * xdr_pad_size - Calculate XDR padding size
+ * @len: Actual size of object being XDR encoded (in bytes)
+ *
+ * Return value:
+ * Size (in bytes) of needed XDR padding
+ */
+static inline size_t
+xdr_pad_size(size_t len)
+{
+ return xdr_align_size(len) - len;
+}
+
/*
* Generic opaque `network object.' At the kernel level, this type
* is used only by lockd.
@@ -39,9 +67,6 @@ struct xdr_netobj {
* Features a header (for a linear buffer containing RPC headers
* and the data payload for short messages), and then an array of
* pages.
- * The tail iovec allows you to append data after the page array. Its
- * main interest is for appending padding to the pages in order to
- * satisfy the int_32-alignment requirements in RFC1832.
*
* For the future, we might want to string several of these together
* in a list if anybody wants to make use of NFSv4 COMPOUND
@@ -55,6 +80,7 @@ struct xdr_buf {
struct page ** pages; /* Array of pages */
unsigned int page_base, /* Start of page data */
page_len, /* Length of page data */
+ page_pad, /* XDR padding needed for pages */
flags; /* Flags for data disposition */
#define XDRBUF_READ 0x01 /* target of file read */
#define XDRBUF_WRITE 0x02 /* source of file write */
@@ -72,11 +98,39 @@ struct xdr_buf {
buf->tail[0].iov_len = 0;
buf->pages = NULL;
buf->page_len = 0;
+ buf->page_pad = 0;
buf->flags = 0;
buf->len = 0;
buf->buflen = len;
}
+/**
+ * xdr_buf_set_pagelen - Set the length of the page list
+ * @buf: XDR buffer containing a message
+ * @len: Size of @buf's page list (in bytes)
+ *
+ */
+static inline void
+xdr_buf_set_pagelen(struct xdr_buf *buf, size_t len)
+{
+ buf->page_len = len;
+ buf->page_pad = xdr_pad_size(len);
+}
+
+/**
+ * xdr_buf_msglen - Return the length of the content in @buf
+ * @buf: XDR buffer containing an XDR-encoded message
+ *
+ * Return value:
+ * Size (in bytes) of the content in @buf
+ */
+static inline size_t
+xdr_buf_msglen(const struct xdr_buf *buf)
+{
+ return buf->head[0].iov_len + buf->page_len + buf->page_pad +
+ buf->tail[0].iov_len;
+}
+
/*
* pre-xdr'ed macros.
*/
@@ -285,20 +339,6 @@ ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str,
size_t size);
ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
size_t maxlen, gfp_t gfp_flags);
-/**
- * xdr_align_size - Calculate padded size of an object
- * @n: Size of an object being XDR encoded (in bytes)
- *
- * Return value:
- * Size (in bytes) of the object including xdr padding
- */
-static inline size_t
-xdr_align_size(size_t n)
-{
- const size_t mask = sizeof(__u32) - 1;
-
- return (n + mask) & ~mask;
-}
/**
* xdr_stream_encode_u32 - Encode a 32-bit integer
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 187dd4e73d64..63a3afac7100 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1516,7 +1516,7 @@ static __printf(2,3) void svc_printk(struct svc_rqst *rqstp, const char *fmt, ..
rqstp->rq_res.pages = rqstp->rq_respages + 1;
rqstp->rq_res.len = 0;
rqstp->rq_res.page_base = 0;
- rqstp->rq_res.page_len = 0;
+ xdr_buf_set_pagelen(&rqstp->rq_res, 0);
rqstp->rq_res.buflen = PAGE_SIZE;
rqstp->rq_res.tail[0].iov_base = NULL;
rqstp->rq_res.tail[0].iov_len = 0;
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index de3c077733a7..032c3bc91d43 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -510,7 +510,7 @@ static void svc_xprt_release(struct svc_rqst *rqstp)
rqstp->rq_deferred = NULL;
svc_free_res_pages(rqstp);
- rqstp->rq_res.page_len = 0;
+ xdr_buf_set_pagelen(&rqstp->rq_res, 0);
rqstp->rq_res.page_base = 0;
/* Reset response buffer and release
@@ -666,7 +666,7 @@ static int svc_alloc_arg(struct svc_rqst *rqstp)
arg->pages = rqstp->rq_pages + 1;
arg->page_base = 0;
/* save at least one page for response */
- arg->page_len = (pages-2)*PAGE_SIZE;
+ xdr_buf_set_pagelen(arg, (pages - 2) << PAGE_SHIFT);
arg->len = (pages-1)*PAGE_SIZE;
arg->tail[0].iov_len = 0;
return 0;
@@ -902,9 +902,13 @@ int svc_send(struct svc_rqst *rqstp)
/* calculate over-all length */
xb = &rqstp->rq_res;
- xb->len = xb->head[0].iov_len +
- xb->page_len +
- xb->tail[0].iov_len;
+ xb->len = xdr_buf_msglen(xb);
+ if ((xb->head[0].iov_len & 3) != 0)
+ trace_printk("head=[%p,%zu] page=%u/%u tail=[%p,%zu] msglen=%zu buflen=%u",
+ xb->head[0].iov_base, xb->head[0].iov_len,
+ xb->page_len, xb->page_pad,
+ xb->tail[0].iov_base, xb->tail[0].iov_len,
+ xdr_buf_msglen(xb), xb->buflen);
/* Grab mutex to serialize outgoing data. */
mutex_lock(&xprt->xpt_mutex);
