The patch titled Subject: buffer: convert block_page_mkwrite() to use a folio has been added to the -mm mm-unstable branch. Its filename is buffer-convert-block_page_mkwrite-to-use-a-folio.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/buffer-convert-block_page_mkwrite-to-use-a-folio.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: buffer: convert block_page_mkwrite() to use a folio Date: Mon, 12 Jun 2023 22:01:34 +0100 If any page in a folio is dirtied, dirty the entire folio. Removes a number of hidden calls to compound_head() and references to page->mapping and page->index. Fixes a pre-existing bug where we could mark a folio as dirty if the file is truncated to a multiple of the page size just as we take the page fault. I don't believe this bug has any bad effect, it's just inefficient. Link: https://lkml.kernel.org/r/20230612210141.730128-8-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx> Cc: Bob Peterson <rpeterso@xxxxxxxxxx> Cc: Hannes Reinecke <hare@xxxxxxxx> Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/buffer.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) --- a/fs/buffer.c~buffer-convert-block_page_mkwrite-to-use-a-folio +++ a/fs/buffer.c @@ -2564,38 +2564,37 @@ EXPORT_SYMBOL(block_commit_write); int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, get_block_t get_block) { - struct page *page = vmf->page; + struct folio *folio = page_folio(vmf->page); struct inode *inode = file_inode(vma->vm_file); unsigned long end; loff_t size; int ret; - lock_page(page); + folio_lock(folio); size = i_size_read(inode); - if ((page->mapping != inode->i_mapping) || - (page_offset(page) > size)) { + if ((folio->mapping != inode->i_mapping) || + (folio_pos(folio) >= size)) { /* We overload EFAULT to mean page got truncated */ ret = -EFAULT; goto out_unlock; } - /* page is wholly or partially inside EOF */ - if (((page->index + 1) << PAGE_SHIFT) > size) - end = size & ~PAGE_MASK; - else - end = PAGE_SIZE; + end = folio_size(folio); + /* folio is wholly or partially inside EOF */ + if (folio_pos(folio) + end > size) + end = size - folio_pos(folio); - ret = __block_write_begin(page, 0, end, get_block); + ret = __block_write_begin_int(folio, 0, end, get_block, NULL); if (!ret) - ret = block_commit_write(page, 0, end); + ret = block_commit_write(&folio->page, 0, end); if (unlikely(ret < 0)) goto out_unlock; - set_page_dirty(page); - wait_for_stable_page(page); + folio_mark_dirty(folio); + folio_wait_stable(folio); return 0; out_unlock: - unlock_page(page); + folio_unlock(folio); return ret; } EXPORT_SYMBOL(block_page_mkwrite); _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are gfs2-use-a-folio-inside-gfs2_jdata_writepage.patch gfs2-pass-a-folio-to-__gfs2_jdata_write_folio.patch gfs2-convert-gfs2_write_jdata_page-to-gfs2_write_jdata_folio.patch buffer-convert-__block_write_full_page-to-__block_write_full_folio.patch gfs2-support-ludicrously-large-folios-in-gfs2_trans_add_databufs.patch buffer-make-block_write_full_page-handle-large-folios-correctly.patch buffer-convert-block_page_mkwrite-to-use-a-folio.patch buffer-convert-__block_commit_write-to-take-a-folio.patch buffer-convert-page_zero_new_buffers-to-folio_zero_new_buffers.patch buffer-convert-grow_dev_page-to-use-a-folio.patch buffer-convert-init_page_buffers-to-folio_init_buffers.patch buffer-convert-link_dev_buffers-to-take-a-folio.patch buffer-use-a-folio-in-__find_get_block_slow.patch buffer-convert-block_truncate_page-to-use-a-folio.patch