[Cluster-devel] [PATCH v3 2/3] iomap: Don't create iomap_page objects for inline files

[Matthew Wilcox <willy@infradead.org>]

On Wed, Jul 07, 2021 at 01:55:23PM +0200, Andreas Gruenbacher wrote:
> @@ -252,6 +253,7 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
>  	}
>  
>  	/* zero post-eof blocks as the page may be mapped */
> +	iop = iomap_page_create(inode, page);
>  	iomap_adjust_read_range(inode, iop, &pos, length, &poff, &plen);
>  	if (plen == 0)
>  		goto done;

I /think/ a subsequent patch would look like this:

+	/* No need to create an iop if the page is within an extent */
+	loff_t page_pos = page_offset(page);
+	if (pos > page_pos || pos + length < page_pos + page_size(page))
+		iop = iomap_page_create(inode, page);

but that might miss some other reasons to create an iop.