Commit 43f0f081 authored by Anna Schumaker's avatar Anna Schumaker
Browse files

SUNRPC: Split out _shift_data_right_tail() 



xdr_shrink_pagelen() is very similar to what we need for hole expansion,
so split out the common code into its own function that can be used by
both functions.

Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent 06216ecb

net/sunrpc/xdr.c

+41 −27
Original line number Diff line number Diff line
@@ -266,6 +266,46 @@ _shift_data_right_pages(struct page **pages, size_t pgto_base, 
	} while ((len -= copy) != 0);

}



static unsigned int

_shift_data_right_tail(struct xdr_buf *buf, unsigned int pgfrom, size_t len)

{

	struct kvec *tail = buf->tail;

	unsigned int tailbuf_len;

	unsigned int result = 0;

	size_t copy;



	tailbuf_len = buf->buflen - buf->head->iov_len - buf->page_len;



	/* Shift the tail first */

	if (tailbuf_len != 0) {

		unsigned int free_space = tailbuf_len - tail->iov_len;



		if (len < free_space)

			free_space = len;

		if (len > free_space)

			len = free_space;



		tail->iov_len += free_space;

		copy = len;



		if (tail->iov_len > len) {

			char *p = (char *)tail->iov_base + len;

			memmove(p, tail->iov_base, tail->iov_len - free_space);

			result += tail->iov_len - free_space;

		} else

			copy = tail->iov_len;



		/* Copy from the inlined pages into the tail */

		_copy_from_pages((char *)tail->iov_base,

					 buf->pages,

					 buf->page_base + pgfrom,

					 copy);

		result += copy;

	}



	return result;

}



/**

 * _copy_to_pages

 * @pages: array of pages
@@ -446,39 +486,13 @@ xdr_shrink_bufhead(struct xdr_buf *buf, size_t len) 
static unsigned int

xdr_shrink_pagelen(struct xdr_buf *buf, size_t len)

{

	struct kvec *tail;

	size_t copy;

	unsigned int pglen = buf->page_len;

	unsigned int tailbuf_len;

	unsigned int result;



	result = 0;

	tail = buf->tail;

	if (len > buf->page_len)

		len = buf-> page_len;

	tailbuf_len = buf->buflen - buf->head->iov_len - buf->page_len;



	/* Shift the tail first */

	if (tailbuf_len != 0) {

		unsigned int free_space = tailbuf_len - tail->iov_len;



		if (len < free_space)

			free_space = len;

		tail->iov_len += free_space;



		copy = len;

		if (tail->iov_len > len) {

			char *p = (char *)tail->iov_base + len;

			memmove(p, tail->iov_base, tail->iov_len - len);

			result += tail->iov_len - len;

		} else

			copy = tail->iov_len;

		/* Copy from the inlined pages into the tail */

		_copy_from_pages((char *)tail->iov_base,

				buf->pages, buf->page_base + pglen - len,

				copy);

		result += copy;

	}

	result = _shift_data_right_tail(buf, pglen - len, len);

	buf->page_len -= len;

	buf->buflen -= len;

	/* Have we truncated the message? */