From cf1f08cac375630af6b6307907a3fc20fcf847c7 Mon Sep 17 00:00:00 2001 From: Anna Schumaker Date: Fri, 17 Apr 2020 11:00:24 -0400 Subject: [PATCH] SUNRPC: Implement a xdr_page_pos() function I'll need this for READ_PLUS to help figure out the offset where page data is stored at, but it might also be useful for other things. Signed-off-by: Anna Schumaker --- include/linux/sunrpc/xdr.h | 1 + net/sunrpc/xdr.c | 13 +++++++++++++ 2 files changed, 14 insertions(+) diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h index 5a6a81b7cd9f..25a68dd87ecf 100644 --- a/include/linux/sunrpc/xdr.h +++ b/include/linux/sunrpc/xdr.h @@ -240,6 +240,7 @@ extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen); extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base, unsigned int len); extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr); +extern unsigned int xdr_page_pos(const struct xdr_stream *xdr); extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p, struct rpc_rqst *rqst); extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index fa7517c1d125..909920fab93b 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -505,6 +505,19 @@ unsigned int xdr_stream_pos(const struct xdr_stream *xdr) } EXPORT_SYMBOL_GPL(xdr_stream_pos); +/** + * xdr_page_pos - Return the current offset from the start of the xdr pages + * @xdr: pointer to struct xdr_stream + */ +unsigned int xdr_page_pos(const struct xdr_stream *xdr) +{ + unsigned int pos = xdr_stream_pos(xdr); + + WARN_ON(pos < xdr->buf->head[0].iov_len); + return pos - xdr->buf->head[0].iov_len; +} +EXPORT_SYMBOL_GPL(xdr_page_pos); + /** * xdr_init_encode - Initialize a struct xdr_stream for sending data. * @xdr: pointer to xdr_stream struct