From 9060bc4d3aca6106bbe72891efba391d9d6b86e7 Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Sun, 15 Jan 2023 08:49:12 -0800 Subject: iomap/gfs2: Get page in page_prepare handler Change the iomap ->page_prepare() handler to get and return a locked folio instead of doing that in iomap_write_begin(). This allows to recover from out-of-memory situations in ->page_prepare(), which eliminates the corresponding error handling code in iomap_write_begin(). The ->put_folio() handler now also isn't called with NULL as the folio value anymore. Filesystems are expected to use the iomap_get_folio() helper for getting locked folios in their ->page_prepare() handlers. Signed-off-by: Andreas Gruenbacher Reviewed-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Darrick J. Wong --- fs/iomap/buffered-io.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) (limited to 'fs/iomap') diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index de4a8e5f721a..418519dea2ce 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -609,7 +609,7 @@ static void __iomap_put_folio(struct iomap_iter *iter, loff_t pos, size_t ret, if (page_ops && page_ops->put_folio) { page_ops->put_folio(iter->inode, pos, ret, folio); - } else if (folio) { + } else { folio_unlock(folio); folio_put(folio); } @@ -642,17 +642,12 @@ static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, if (!mapping_large_folio_support(iter->inode->i_mapping)) len = min_t(size_t, len, PAGE_SIZE - offset_in_page(pos)); - if (page_ops && page_ops->page_prepare) { - status = page_ops->page_prepare(iter->inode, pos, len); - if (status) - return status; - } - - folio = iomap_get_folio(iter, pos); - if (IS_ERR(folio)) { - __iomap_put_folio(iter, pos, 0, NULL); + if (page_ops && page_ops->page_prepare) + folio = page_ops->page_prepare(iter, pos, len); + else + folio = iomap_get_folio(iter, pos); + if (IS_ERR(folio)) return PTR_ERR(folio); - } /* * Now we have a locked folio, before we do anything with it we need to -- cgit v1.2.3