Unverified Commit a060d835 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Christian Brauner
Browse files

fuse: Convert fuse_write_begin() to use a folio 



Fetch a folio from the page cache instead of a page and use it throughout
removing several calls to compound_head() and supporting large folios
(in this function).  We still have to convert back to a page for calling
internal fuse functions, but hopefully they will be converted soon.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 556d0ac0

fs/fuse/file.c

+15 −14
Original line number Diff line number Diff line
@@ -2391,41 +2391,42 @@ static int fuse_write_begin(struct file *file, struct address_space *mapping, 
{

	pgoff_t index = pos >> PAGE_SHIFT;

	struct fuse_conn *fc = get_fuse_conn(file_inode(file));

	struct page *page;

	struct folio *folio;

	loff_t fsize;

	int err = -ENOMEM;



	WARN_ON(!fc->writeback_cache);



	page = grab_cache_page_write_begin(mapping, index);

	if (!page)

	folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,

			mapping_gfp_mask(mapping));

	if (IS_ERR(folio))

		goto error;



	fuse_wait_on_page_writeback(mapping->host, page->index);

	fuse_wait_on_page_writeback(mapping->host, folio->index);



	if (PageUptodate(page) || len == PAGE_SIZE)

	if (folio_test_uptodate(folio) || len >= folio_size(folio))

		goto success;

	/*

	 * Check if the start this page comes after the end of file, in which

	 * case the readpage can be optimized away.

	 * Check if the start of this folio comes after the end of file,

	 * in which case the readpage can be optimized away.

	 */

	fsize = i_size_read(mapping->host);

	if (fsize <= (pos & PAGE_MASK)) {

		size_t off = pos & ~PAGE_MASK;

	if (fsize <= folio_pos(folio)) {

		size_t off = offset_in_folio(folio, pos);

		if (off)

			zero_user_segment(page, 0, off);

			folio_zero_segment(folio, 0, off);

		goto success;

	}

	err = fuse_do_readpage(file, page);

	err = fuse_do_readpage(file, &folio->page);

	if (err)

		goto cleanup;

success:

	*pagep = page;

	*pagep = &folio->page;

	return 0;



cleanup:

	unlock_page(page);

	put_page(page);

	folio_unlock(folio);

	folio_put(folio);

error:

	return err;

}