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charset=us-ascii Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 04342A0012 X-Stat-Signature: 1qsczotj7icd7puwjbuq5351q3oq73xi X-HE-Tag: 1775628674-891777 X-HE-Meta: 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 0St822Lu sx6bYbkMLiGdKECa1b4rsOQ4gpo2xrkph/PF/V4a+M30TAnmJKoaKpgrg2VZH84szZYS2amZHP6vhyzC6M4HZvPJuokrkmG9SQbJ9PqGYyJEwy2Za/z5qvMaYZ5CcIFRrHphMWaaXGkV8uNjl8a8kuI3b37o5oUq5cMTTekcOoWgUEdjkB91Qh5bDrONBzxG2dblI1f8rWCPNjsPlfqmFmrNYOspXI3EC8G2Poib9JuUsnq9AFO9PZ+o89C2KmyoYHPj5V8R0Nnmi05Cj+w61HCnb2CbDrNGwuQjkqe6a2014hajSptd+rEmjXwnfUwIYyFuguVVr04oeEjO+lmT0O879dL6aZKCtU69rEqlzCZMW//4wt6rb+OhzpAEYwtrLNh3rO/IpIxtc9Xcjwh8zkUA030hMphCuxymiqbeyW48VubG/CCFvuqn5WU51O3H0ygWkqYje2VvYU8g= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 03/30/26 at 08:30pm, Chris Li wrote: ...... > > @@ -608,6 +593,39 @@ static void swap_read_folio_bdev_async(struct folio *folio, > > submit_bio(bio); > > } > > > > +static const struct swap_ops bdev_fs_swap_ops = { > > + .read_folio = swap_read_folio_fs, > > + .write_folio = swap_writepage_fs, > > +}; > > + > > +static const struct swap_ops bdev_sync_swap_ops = { > > + .read_folio = swap_read_folio_bdev_sync, > > + .write_folio = swap_writepage_bdev_sync, > > +}; > > + > > +static const struct swap_ops bdev_async_swap_ops = { > > + .read_folio = swap_read_folio_bdev_async, > > + .write_folio = swap_writepage_bdev_async, > > +}; > > + > > +void setup_swap_ops(struct swap_info_struct *sis) > > setup_swap_ops()` needs to return an indication of an error. > The error is that sis->ops is NULL or op->read_folio == NULL or > op->write_folio == NULL. > If there is an error, we should fail the swapon. Thanks for your comments. In the current patches, there's no chance any of these happens: sis->ops is NULL or op->read_folio == NULL or op->write_folio == NULL Because it's a if-else logic in setup_swap_ops(), adding an error checking looks a little weird. I think it's worth adding the error checking in setup_swap_ops() later when we have new swap_ops added and there's potential any of above three cases could happen. What do you think? Thanks Baoquan