diff options
Diffstat (limited to 'fs/mpage.c')
-rw-r--r-- | fs/mpage.c | 38 |
1 files changed, 11 insertions, 27 deletions
diff --git a/fs/mpage.c b/fs/mpage.c index ccba3c4c4479..830e6cc2a9e7 100644 --- 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; } |