Re: [PATCH] fs/ntfs3: remove ntfs_bio_pages and use page cache for compressed I/O

[Matthew Wilcox]

On Fri, Oct 31, 2025 at 08:15:16AM +0100, Konstantin Komarov wrote:
> Replace the use of ntfs_bio_pages with the disk page cache for reading and
> writing compressed files. This slightly improves performance when reading
> compressed data and simplifies the I/O logic.

Yes, this is a good improvement.

> +		/* Read range [lbo, lbo+len). */
> +		page = read_mapping_page(mapping, lbo >> PAGE_SHIFT, NULL);

I'm not keen on this though.  read_mapping_page() is deprecated; please
use read_mapping_folio().

> +		kaddr = kmap_local_page(page);

kmap_local_folio()

> +		if (wr) {
> +			memcpy(kaddr + off, buf, op);
> +			set_page_dirty(page);

folio_mark_dirty()

> +		} else {
> +			memcpy(buf, kaddr + off, op);
> +			flush_dcache_page(page);

flush_dcache_folio()

> +		}
> +		kunmap_local(kaddr);
> +		put_page(page);

folio_put()