CIFS: Separate page search from readpages
Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index c79bdf3..bec48f1 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3340,6 +3340,63 @@
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 @@
* 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);
+ rc = readpages_get_pages(mapping, page_list, rsize, &tmplist,
+ &nr_pages, &offset, &bytes);
+ if (rc)
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);
- 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) {