SUNRPC: xdr_read_pages should return the amount of XDR encoded page data

Callers of xdr_read_pages() will want to know exactly how much XDR
data is encoded in the pages after the data realignment.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index f1e7f884d1c3a2334ee236e3e1ea71fba9f46e80..2489bce1fb88e713ab468ce70cdcd394ad773104 100644 (file)
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -223,7 +223,7 @@ extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
                struct page **pages, unsigned int len);
 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
-extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
+extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 5643feb6c6453e7965a047a76fd8bd3cf7157873..80d518644cf8273afd74426e0e816e2f16dc35b9 100644 (file)
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -745,8 +745,10 @@ EXPORT_SYMBOL_GPL(xdr_inline_decode);
  * Moves data beyond the current pointer position from the XDR head[] buffer
  * into the page list. Any data that lies beyond current position + "len"
  * bytes is moved into the XDR tail[].
+ *
+ * Returns the number of XDR encoded bytes now contained in the pages
  */
-void xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
+unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
 {
        struct xdr_buf *buf = xdr->buf;
        struct kvec *iov;
@@ -756,7 +758,7 @@ void xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
        int padding;
 
        if (xdr->nwords == 0)
-               return;
+               return 0;
        if (nwords > xdr->nwords) {
                nwords = xdr->nwords;
                len = nwords << 2;
@@ -787,6 +789,7 @@ void xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
        xdr->end = (__be32 *)((char *)iov->iov_base + end);
        xdr->page_ptr = NULL;
        xdr->nwords = XDR_QUADLEN(end - padding);
+       return len;
 }
 EXPORT_SYMBOL_GPL(xdr_read_pages);
 
@@ -802,7 +805,7 @@ EXPORT_SYMBOL_GPL(xdr_read_pages);
  */
 void xdr_enter_page(struct xdr_stream *xdr, unsigned int len)
 {
-       xdr_read_pages(xdr, len);
+       len = xdr_read_pages(xdr, len);
        /*
         * Position current pointer at beginning of tail, and
         * set remaining message length.