On Fri, Jan 24, 2020 at 05:35:48PM -0800, Matthew Wilcox wrote:
> From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
>
> Use the new readahead operation in erofs. Fix what I believe to be
> a refcounting bug in the error case.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Cc: linux-erofs@xxxxxxxxxxxxxxxx
> ---
> fs/erofs/data.c | 34 ++++++++++++++--------------------
> fs/erofs/zdata.c | 2 +-
> include/trace/events/erofs.h | 6 +++---
> 3 files changed, 18 insertions(+), 24 deletions(-)
>
> diff --git a/fs/erofs/data.c b/fs/erofs/data.c
> index fc3a8d8064f8..335c1ab05312 100644
> --- a/fs/erofs/data.c
> +++ b/fs/erofs/data.c
> @@ -280,42 +280,36 @@ static int erofs_raw_access_readpage(struct file *file, struct page *page)
> return 0;
> }
>
> -static int erofs_raw_access_readpages(struct file *filp,
> +static unsigned erofs_raw_access_readahead(struct file *file,
> struct address_space *mapping,
> - struct list_head *pages,
> + pgoff_t start,
> unsigned int nr_pages)
> {
> erofs_off_t last_block;
> struct bio *bio = NULL;
> - gfp_t gfp = readahead_gfp_mask(mapping);
> - struct page *page = list_last_entry(pages, struct page, lru);
>
> - trace_erofs_readpages(mapping->host, page, nr_pages, true);
> + trace_erofs_readpages(mapping->host, start, nr_pages, true);
>
> for (; nr_pages; --nr_pages) {
> - page = list_entry(pages->prev, struct page, lru);
> + struct page *page = readahead_page(mapping, start++);
>
> prefetchw(&page->flags);
> - list_del(&page->lru);
>
> - if (!add_to_page_cache_lru(page, mapping, page->index, gfp)) {
> - bio = erofs_read_raw_page(bio, mapping, page,
> - &last_block, nr_pages, true);
> + bio = erofs_read_raw_page(bio, mapping, page, &last_block,
> + nr_pages, true);
>
> - /* all the page errors are ignored when readahead */
> - if (IS_ERR(bio)) {
> - pr_err("%s, readahead error at page %lu of nid %llu\n",
> - __func__, page->index,
> - EROFS_I(mapping->host)->nid);
> + /* all the page errors are ignored when readahead */
> + if (IS_ERR(bio)) {
> + pr_err("%s, readahead error at page %lu of nid %llu\n",
> + __func__, page->index,
> + EROFS_I(mapping->host)->nid);
>
> - bio = NULL;
> - }
> + bio = NULL;
> + put_page(page);
> }
>
> - /* pages could still be locked */
> put_page(page);
A double put_page() on error?
Cheers,
Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx
