Commit e1bd8760 authored by Anna Schumaker's avatar Anna Schumaker Committed by Trond Myklebust
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SUNRPC: Add a function for zeroing out a portion of an xdr_stream 



This will be used during READ_PLUS decoding for handling HOLE segments.

Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
parent 7c4cd5f4

include/linux/sunrpc/xdr.h

+2 −0
Original line number Diff line number Diff line
@@ -265,6 +265,8 @@ extern bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf 
				  unsigned int len);

extern unsigned int xdr_stream_move_subsegment(struct xdr_stream *xdr, unsigned int offset,

					       unsigned int target, unsigned int length);

extern unsigned int xdr_stream_zero(struct xdr_stream *xdr, unsigned int offset,

				    unsigned int length);



/**

 * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data.

net/sunrpc/xdr.c

+23 −0
Original line number Diff line number Diff line
@@ -1769,6 +1769,29 @@ unsigned int xdr_stream_move_subsegment(struct xdr_stream *xdr, unsigned int off 
}

EXPORT_SYMBOL_GPL(xdr_stream_move_subsegment);



/**

 * xdr_stream_zero - zero out a portion of an xdr_stream

 * @xdr: an xdr_stream to zero out

 * @offset: the starting point in the stream

 * @length: the number of bytes to zero

 */

unsigned int xdr_stream_zero(struct xdr_stream *xdr, unsigned int offset,

			     unsigned int length)

{

	struct xdr_buf buf;



	if (xdr_buf_subsegment(xdr->buf, &buf, offset, length) < 0)

		return 0;

	if (buf.head[0].iov_len)

		xdr_buf_iov_zero(buf.head, 0, buf.head[0].iov_len);

	if (buf.page_len > 0)

		xdr_buf_pages_zero(&buf, 0, buf.page_len);

	if (buf.tail[0].iov_len)

		xdr_buf_iov_zero(buf.tail, 0, buf.tail[0].iov_len);

	return length;

}

EXPORT_SYMBOL_GPL(xdr_stream_zero);



/**

 * xdr_buf_trim - lop at most "len" bytes off the end of "buf"

 * @buf: buf to be trimmed