From fe181377a23cce5987fc32f1877cfcd223561609 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 12 Jun 2023 22:01:34 +0100 Subject: buffer: convert block_page_mkwrite() to use a folio 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@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Cc: Andreas Gruenbacher Cc: Bob Peterson Cc: Hannes Reinecke Cc: Luis Chamberlain Signed-off-by: Andrew Morton --- fs/buffer.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 34ecf55d2f12..0af167e8a9c6 100644 --- a/fs/buffer.c +++ b/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); -- cgit v1.2.3