Add a new xdr helper function that shifts the data in an xdr
buffer's head to make room for new data.
Also add an export for the helper function write_bytes_to_xdr_buf().
Signed-off-by: Kevin Coffman <[email protected]>
---
include/linux/sunrpc/xdr.h | 2 ++
net/sunrpc/xdr.c | 29 +++++++++++++++++++++++++++++
2 files changed, 31 insertions(+), 0 deletions(-)
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index e4057d7..518d47c 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -164,6 +164,8 @@ extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int,
extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
+extern int xdr_shift_head_data(struct xdr_buf *, int, unsigned int);
+
/*
* Helper structure for copying from an sk_buff.
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 995c3fd..de2c986 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -428,6 +428,34 @@ xdr_shift_buf(struct xdr_buf *buf, size_t len)
EXPORT_SYMBOL(xdr_shift_buf);
/**
+ * xdr_xdr_shift_head_data - Make room for new data within buf->head
+ * @buf: pointer to XDR buffer
+ * @offset: offset within the head to start moving data
+ * @shiftlen: number of bytes to shift the data
+ */
+int
+xdr_shift_head_data(struct xdr_buf *buf, int offset, unsigned int shiftlen)
+{
+ u8 *p;
+
+ if (shiftlen == 0)
+ return 0;
+ /* make sure there is room (assuming head has a page) */
+ if (buf->head[0].iov_len + shiftlen + offset > PAGE_CACHE_SIZE)
+ return 1;
+
+ p = buf->head[0].iov_base + offset;
+
+ memmove(p + shiftlen, p, buf->head[0].iov_len - offset);
+
+ buf->head[0].iov_len += shiftlen;
+ buf->len += shiftlen;
+
+ return 0;
+}
+EXPORT_SYMBOL(xdr_shift_head_data);
+
+/**
* xdr_init_encode - Initialize a struct xdr_stream for sending data.
* @xdr: pointer to xdr_stream struct
* @buf: pointer to XDR buffer in which to encode data
@@ -758,6 +786,7 @@ int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, un
__write_bytes_to_xdr_buf(&subbuf, obj, len);
return 0;
}
+EXPORT_SYMBOL(write_bytes_to_xdr_buf);
int
xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj)