Commit 387eb92a authored by Pavel Shilovsky's avatar Pavel Shilovsky Committed by Steve French
Browse files

CIFS: Separate page search from readpages 



Reviewed-by: default avatarShirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: default avatarPavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: default avatarSteve French <smfrench@gmail.com>
parent cb7e9eab

fs/cifs/file.c

+61 −46
Original line number Diff line number Diff line
@@ -3340,6 +3340,63 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server, 
	return total_read > 0 && result != -EAGAIN ? total_read : result;

}



static int

readpages_get_pages(struct address_space *mapping, struct list_head *page_list,

		    unsigned int rsize, struct list_head *tmplist,

		    unsigned int *nr_pages, loff_t *offset, unsigned int *bytes)

{

	struct page *page, *tpage;

	unsigned int expected_index;

	int rc;



	page = list_entry(page_list->prev, struct page, lru);



	/*

	 * Lock the page and put it in the cache. Since no one else

	 * should have access to this page, we're safe to simply set

	 * PG_locked without checking it first.

	 */

	__set_page_locked(page);

	rc = add_to_page_cache_locked(page, mapping,

				      page->index, GFP_KERNEL);



	/* give up if we can't stick it in the cache */

	if (rc) {

		__clear_page_locked(page);

		return rc;

	}



	/* move first page to the tmplist */

	*offset = (loff_t)page->index << PAGE_CACHE_SHIFT;

	*bytes = PAGE_CACHE_SIZE;

	*nr_pages = 1;

	list_move_tail(&page->lru, tmplist);



	/* now try and add more pages onto the request */

	expected_index = page->index + 1;

	list_for_each_entry_safe_reverse(page, tpage, page_list, lru) {

		/* discontinuity ? */

		if (page->index != expected_index)

			break;



		/* would this page push the read over the rsize? */

		if (*bytes + PAGE_CACHE_SIZE > rsize)

			break;



		__set_page_locked(page);

		if (add_to_page_cache_locked(page, mapping, page->index,

								GFP_KERNEL)) {

			__clear_page_locked(page);

			break;

		}

		list_move_tail(&page->lru, tmplist);

		(*bytes) += PAGE_CACHE_SIZE;

		expected_index++;

		(*nr_pages)++;

	}

	return rc;

}



static int cifs_readpages(struct file *file, struct address_space *mapping,

	struct list_head *page_list, unsigned num_pages)

{
@@ -3394,57 +3451,15 @@ static int cifs_readpages(struct file *file, struct address_space *mapping, 
	 * the rdata->pages, then we want them in increasing order.

	 */

	while (!list_empty(page_list)) {

		unsigned int i;

		unsigned int bytes = PAGE_CACHE_SIZE;

		unsigned int expected_index;

		unsigned int nr_pages = 1;

		unsigned int i, nr_pages, bytes;

		loff_t offset;

		struct page *page, *tpage;

		struct cifs_readdata *rdata;



		page = list_entry(page_list->prev, struct page, lru);



		/*

		 * Lock the page and put it in the cache. Since no one else

		 * should have access to this page, we're safe to simply set

		 * PG_locked without checking it first.

		 */

		__set_page_locked(page);

		rc = add_to_page_cache_locked(page, mapping,

					      page->index, GFP_KERNEL);



		/* give up if we can't stick it in the cache */

		if (rc) {

			__clear_page_locked(page);

			break;

		}



		/* move first page to the tmplist */

		offset = (loff_t)page->index << PAGE_CACHE_SHIFT;

		list_move_tail(&page->lru, &tmplist);



		/* now try and add more pages onto the request */

		expected_index = page->index + 1;

		list_for_each_entry_safe_reverse(page, tpage, page_list, lru) {

			/* discontinuity ? */

			if (page->index != expected_index)

				break;



			/* would this page push the read over the rsize? */

			if (bytes + PAGE_CACHE_SIZE > rsize)

				break;



			__set_page_locked(page);

			if (add_to_page_cache_locked(page, mapping,

						page->index, GFP_KERNEL)) {

				__clear_page_locked(page);

		rc = readpages_get_pages(mapping, page_list, rsize, &tmplist,

					 &nr_pages, &offset, &bytes);

		if (rc)

			break;

			}

			list_move_tail(&page->lru, &tmplist);

			bytes += PAGE_CACHE_SIZE;

			expected_index++;

			nr_pages++;

		}



		rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);

		if (!rdata) {