On 10/30/20 7:51 AM, Naohiro Aota wrote: > From: Johannes Thumshirn <johannes.thumshirn@xxxxxxx> > > Add bio_add_zone_append_page(), a wrapper around bio_add_hw_page() which > is intended to be used by file systems that directly add pages to a bio > instead of using bio_iov_iter_get_pages(). Not sure what this is for, since I'm only on one patch in the series... > +/** > + * bio_add_zone_append_page - attempt to add page to zone-append bio > + * @bio: destination bio > + * @page: page to add > + * @len: vec entry length > + * @offset: vec entry offset > + * > + * Attempt to add a page to the bio_vec maplist of a bio that will be submitted > + * for a zone-append request. This can fail for a number of reasons, such as the > + * bio being full or the target block device is not a zoned block device or > + * other limitations of the target block device. The target block device must > + * allow bio's up to PAGE_SIZE, so it is always possible to add a single page > + * to an empty bio. > + */ This should include a Return value: section, explaining how it returns number of bytes added (and why 0 is thus a failure case). > +int bio_add_zone_append_page(struct bio *bio, struct page *page, > + unsigned int len, unsigned int offset) Should this return unsigned int? If not, how would it work if someone asked for INT_MAX + 4k. -- Jens Axboe
