Merge branch 'uaccess.csum' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

[tomoyo/tomoyo-test1.git] / fs / mpage.c

diff --git a/fs/mpage.c b/fs/mpage.c
index ccba3c4..830e6cc 100644 (file)
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -91,7 +91,7 @@ mpage_alloc(struct block_device *bdev,
 }
 
 /*
- * support function for mpage_readpages.  The fs supplied get_block might
+ * support function for mpage_readahead.  The fs supplied get_block might
  * return an up to date buffer.  This is used to map that buffer into
  * the page, which allows readpage to avoid triggering a duplicate call
  * to get_block.
@@ -338,13 +338,8 @@ confused:
 }
 
 /**
- * mpage_readpages - populate an address space with some pages & start reads against them
- * @mapping: the address_space
- * @pages: The address of a list_head which contains the target pages.  These
- *   pages have their ->index populated and are otherwise uninitialised.
- *   The page at @pages->prev has the lowest file offset, and reads should be
- *   issued in @pages->prev to @pages->next order.
- * @nr_pages: The number of pages at *@pages
+ * mpage_readahead - start reads against pages
+ * @rac: Describes which pages to read.
  * @get_block: The filesystem's block mapper function.
  *
  * This function walks the pages and the blocks within each page, building and
@@ -381,36 +376,25 @@ confused:
  *
  * This all causes the disk requests to be issued in the correct order.
  */
-int
-mpage_readpages(struct address_space *mapping, struct list_head *pages,
-                               unsigned nr_pages, get_block_t get_block)
+void mpage_readahead(struct readahead_control *rac, get_block_t get_block)
 {
+       struct page *page;
        struct mpage_readpage_args args = {
                .get_block = get_block,
                .is_readahead = true,
        };
-       unsigned page_idx;
-
-       for (page_idx = 0; page_idx < nr_pages; page_idx++) {
-               struct page *page = lru_to_page(pages);
 
+       while ((page = readahead_page(rac))) {
                prefetchw(&page->flags);
-               list_del(&page->lru);
-               if (!add_to_page_cache_lru(page, mapping,
-                                       page->index,
-                                       readahead_gfp_mask(mapping))) {
-                       args.page = page;
-                       args.nr_pages = nr_pages - page_idx;
-                       args.bio = do_mpage_readpage(&args);
-               }
+               args.page = page;
+               args.nr_pages = readahead_count(rac);
+               args.bio = do_mpage_readpage(&args);
                put_page(page);
        }
-       BUG_ON(!list_empty(pages));
        if (args.bio)
                mpage_bio_submit(REQ_OP_READ, REQ_RAHEAD, args.bio);
-       return 0;
 }
-EXPORT_SYMBOL(mpage_readpages);
+EXPORT_SYMBOL(mpage_readahead);
 
 /*
  * This isn't called much at all
@@ -563,7 +547,7 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
                 * Page has buffers, but they are all unmapped. The page was
                 * created by pagein or read over a hole which was handled by
                 * block_read_full_page().  If this address_space is also
-                * using mpage_readpages then this can rarely happen.
+                * using mpage_readahead then this can rarely happen.
                 */
                goto confused;
        }