On 5/11/24 00:35, Matthew Wilcox wrote:
On Fri, May 10, 2024 at 12:29:05PM +0200, hare@xxxxxxxxxx wrote:
From: Hannes Reinecke <hare@xxxxxxx>
Call mapping_set_folio_min_order() when modifying the logical block
size to ensure folios are allocated with the correct size.
This makes me nervous. It lets the pagecache allocate folios larger
than min_order (all the way up to PMD_ORDER). Filesystems may not
cope well with seeing tail pages.
I'd _like_ to be able to do this. But I think for now we need to
call mapping_set_folio_order_range(mapping, order, order);
(Misrouted reply to the previous mail; airports make me jumpy ...)
The whole point is that these devices cannot support smaller
allocations. We might restrict ourselves to min_order == max_order,
but we should be focussing on getting min_order working first ...
Cheers,
Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
hare@xxxxxxx +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
