Exemplo n.º 1
0
/**
 * nfs_pageio_do_add_request - Attempt to coalesce a request into a page list.
 * @desc: destination io descriptor
 * @req: request
 *
 * Returns true if the request 'req' was successfully coalesced into the
 * existing list of pages 'desc'.
 */
static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
				     struct nfs_page *req)
{
	size_t newlen = req->wb_bytes;

	if (desc->pg_count != 0) {
		struct nfs_page *prev;

		/*
		 * FIXME: ideally we should be able to coalesce all requests
		 * that are not block boundary aligned, but currently this
		 * is problematic for the case of bsize < PAGE_CACHE_SIZE,
		 * since nfs_flush_multi and nfs_pagein_multi assume you
		 * can have only one struct nfs_page.
		 */
		if (desc->pg_bsize < PAGE_SIZE)
			return 0;
		newlen += desc->pg_count;
		if (newlen > desc->pg_bsize)
			return 0;
		prev = nfs_list_entry(desc->pg_list.prev);
		if (!nfs_can_coalesce_requests(prev, req))
			return 0;
	} else
		desc->pg_base = req->wb_pgbase;
	nfs_list_remove_request(req);
	nfs_list_add_request(req, &desc->pg_list);
	desc->pg_count = newlen;
	return 1;
}
Exemplo n.º 2
0
/**
 * nfs_pageio_do_add_request - Attempt to coalesce a request into a page list.
 * @desc: destination io descriptor
 * @req: request
 *
 * Returns true if the request 'req' was successfully coalesced into the
 * existing list of pages 'desc'.
 */
static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
				     struct nfs_page *req)
{
	if (desc->pg_count != 0) {
		struct nfs_page *prev;

		prev = nfs_list_entry(desc->pg_list.prev);
		if (!nfs_can_coalesce_requests(prev, req, desc))
			return 0;
	} else {
		desc->pg_base = req->wb_pgbase;
	}
	nfs_list_remove_request(req);
	nfs_list_add_request(req, &desc->pg_list);
	desc->pg_count += req->wb_bytes;
	return 1;
}