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See http://www.infradead.org/rpr.html X-Stat-Signature: p7d1bm567taoxoj918eqrkpaxpqhp1xs X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: A9D5C180007 X-Rspam-User: X-HE-Tag: 1778650359-876969 X-HE-Meta: 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 AllAKPwW 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > }; > > +struct swap_ops; > /* Please keep empty spaces before comments. And keeping forward declarations at the beginning of the file makes them much easier to organize (although the current swap.h is a complete mess not only in this regard). > +int init_swap_ops(struct swap_info_struct *sis) > +{ > + /* > + * ->flags can be updated non-atomically, but that will > + * never affect SWP_FS_OPS, so the data_race is safe. > + */ > + if (data_race(sis->flags & SWP_FS_OPS)) > + sis->ops = &bdev_fs_swap_ops; > + /* > + * ->flags can be updated non-atomically, but that will > + * never affect SWP_SYNCHRONOUS_IO, so the data_race is safe. > + */ > + else if (data_race(sis->flags & SWP_SYNCHRONOUS_IO)) > + sis->ops = &bdev_sync_swap_ops; > + else > + sis->ops = &bdev_async_swap_ops; > + > + if (!sis->ops || !sis->ops->read_folio || !sis->ops->write_folio) > + return -EINVAL; In the long run setting these from the helpers for ->swap_activate would make more sense. Also as ls long as the ops are a small statically defined set these checks here are a bit odd. I guess we just need to land this ASAP, then my swap_activate series and then do a big round of cleanups for a coherent swap interface. > - } else if (synchronous) { > - swap_read_folio_bdev_sync(folio, sis); > - } else { > - swap_read_folio_bdev_async(folio, sis); > - } > + sis->ops->read_folio(sis, folio, plug); This is a really annoying double-indirection for the SWP_FS_OPS case. I think we should have one level of indirection here. One way to do this would be to remove the swap_rw operation and implement the swap_ops directly in nfs and cifs.