CIFS: Separate page processing from writepages
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 6b6df30..69d1763 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1878,6 +1878,86 @@
return rc;
}
+static unsigned int
+wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
+ struct address_space *mapping,
+ struct writeback_control *wbc,
+ pgoff_t end, pgoff_t *index, pgoff_t *next, bool *done)
+{
+ unsigned int nr_pages = 0, i;
+ struct page *page;
+
+ for (i = 0; i < found_pages; i++) {
+ page = wdata->pages[i];
+ /*
+ * At this point we hold neither mapping->tree_lock nor
+ * lock on the page itself: the page may be truncated or
+ * invalidated (changing page->mapping to NULL), or even
+ * swizzled back from swapper_space to tmpfs file
+ * mapping
+ */
+
+ if (nr_pages == 0)
+ lock_page(page);
+ else if (!trylock_page(page))
+ break;
+
+ if (unlikely(page->mapping != mapping)) {
+ unlock_page(page);
+ break;
+ }
+
+ if (!wbc->range_cyclic && page->index > end) {
+ *done = true;
+ unlock_page(page);
+ break;
+ }
+
+ if (*next && (page->index != *next)) {
+ /* Not next consecutive page */
+ unlock_page(page);
+ break;
+ }
+
+ if (wbc->sync_mode != WB_SYNC_NONE)
+ wait_on_page_writeback(page);
+
+ if (PageWriteback(page) ||
+ !clear_page_dirty_for_io(page)) {
+ unlock_page(page);
+ break;
+ }
+
+ /*
+ * This actually clears the dirty bit in the radix tree.
+ * See cifs_writepage() for more commentary.
+ */
+ set_page_writeback(page);
+ if (page_offset(page) >= i_size_read(mapping->host)) {
+ *done = true;
+ unlock_page(page);
+ end_page_writeback(page);
+ break;
+ }
+
+ wdata->pages[i] = page;
+ *next = page->index + 1;
+ ++nr_pages;
+ }
+
+ /* reset index to refind any pages skipped */
+ if (nr_pages == 0)
+ *index = wdata->pages[0]->index + 1;
+
+ /* put any pages we aren't going to use */
+ for (i = nr_pages; i < found_pages; i++) {
+ page_cache_release(wdata->pages[i]);
+ wdata->pages[i] = NULL;
+ }
+
+ return nr_pages;
+}
+
static int cifs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
@@ -1886,7 +1966,6 @@
pgoff_t end, index;
struct cifs_writedata *wdata;
struct TCP_Server_Info *server;
- struct page *page;
int rc = 0;
/*
@@ -1944,75 +2023,8 @@
break;
}
- nr_pages = 0;
- for (i = 0; i < found_pages; i++) {
- page = wdata->pages[i];
- /*
- * At this point we hold neither mapping->tree_lock nor
- * lock on the page itself: the page may be truncated or
- * invalidated (changing page->mapping to NULL), or even
- * swizzled back from swapper_space to tmpfs file
- * mapping
- */
-
- if (nr_pages == 0)
- lock_page(page);
- else if (!trylock_page(page))
- break;
-
- if (unlikely(page->mapping != mapping)) {
- unlock_page(page);
- break;
- }
-
- if (!wbc->range_cyclic && page->index > end) {
- done = true;
- unlock_page(page);
- break;
- }
-
- if (next && (page->index != next)) {
- /* Not next consecutive page */
- unlock_page(page);
- break;
- }
-
- if (wbc->sync_mode != WB_SYNC_NONE)
- wait_on_page_writeback(page);
-
- if (PageWriteback(page) ||
- !clear_page_dirty_for_io(page)) {
- unlock_page(page);
- break;
- }
-
- /*
- * This actually clears the dirty bit in the radix tree.
- * See cifs_writepage() for more commentary.
- */
- set_page_writeback(page);
-
- if (page_offset(page) >= i_size_read(mapping->host)) {
- done = true;
- unlock_page(page);
- end_page_writeback(page);
- break;
- }
-
- wdata->pages[i] = page;
- next = page->index + 1;
- ++nr_pages;
- }
-
- /* reset index to refind any pages skipped */
- if (nr_pages == 0)
- index = wdata->pages[0]->index + 1;
-
- /* put any pages we aren't going to use */
- for (i = nr_pages; i < found_pages; i++) {
- page_cache_release(wdata->pages[i]);
- wdata->pages[i] = NULL;
- }
+ nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
+ end, &index, &next, &done);
/* nothing to write? */
if (nr_pages == 0) {