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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 7CFE640010 X-Stat-Signature: qicueem9b5xqkritz4mk5gpyk5zjzy3s X-HE-Tag: 1687840780-553497 X-HE-Meta: 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 kLA5Ppa5 a009O2000c7V4OQvqs19SJJTBQ5tPWPGprRhAueoDxhEIvEu4TaW2E9IOmzoTXIIMYfWnz4FK9QvmrxN7sgFK/HCElYQH+6pALnXFvXy0KF0CftCyXgCZtaaHhbXzeuYcYA0+D93KqGJgqMwNnG1ZX4HC+vPD3pBOpObnXJx2tuEi04DD07mTgITlDFTOC22htKZ/DNiD1/EF4CrWsCpLvIgjiyDVWCWiDhULPsyCZn1MtS+zy0a5MIw1Wuf9ayXxUZIZ6HLIrnr4txGVwa2lN+IdlkhGOfqcRFAZF4Rkh9oERXBhu5W2P3lvR8AmxOm9HTicv4AlWpF6rQsdi/8lNJx7d/3PZEHt36mzl2QlrTJ28MWPrkw/Lfa1EL+D/Qoz+v57fw7ucM/HSjyd+YrOsF/TlEDoz40uxqstVRto9N3+WKNSWrpfUOXRFoaD3CwTupKUEXo/upIMRsiW6LJ68hs8PMtW7W7KxE/O/SZF6iA44/c= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Jun 26, 2023 at 06:35:18PM +0100, Matthew Wilcox (Oracle) wrote: > Pull the post-processing of the writepage_t callback into a > separate function. That means changing writeback_finish() to > return NULL, and writeback_get_next() to call writeback_finish() > when we naturally run out of folios. > > Signed-off-by: Matthew Wilcox (Oracle) > --- > mm/page-writeback.c | 84 ++++++++++++++++++++++++--------------------- > 1 file changed, 44 insertions(+), 40 deletions(-) > > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index 659df2b5c7c0..ef61d7006c5e 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -2360,7 +2360,7 @@ void tag_pages_for_writeback(struct address_space *mapping, > } > EXPORT_SYMBOL(tag_pages_for_writeback); > > -static int writeback_finish(struct address_space *mapping, > +static struct folio *writeback_finish(struct address_space *mapping, > struct writeback_control *wbc, bool done) > { > folio_batch_release(&wbc->fbatch); > @@ -2375,7 +2375,7 @@ static int writeback_finish(struct address_space *mapping, > if (wbc->range_cyclic || (wbc->range_whole && wbc->nr_to_write > 0)) > mapping->writeback_index = wbc->done_index; > > - return wbc->err; > + return NULL; Having a return value that is always NULL feels a bit weird vs just doing that return in the caller. > +static struct folio *writeback_iter_next(struct address_space *mapping, > + struct writeback_control *wbc, struct folio *folio, int error) > +{ > + if (unlikely(error)) { > + /* > + * Handle errors according to the type of writeback. > + * There's no need to continue for background writeback. > + * Just push done_index past this folio so media > + * errors won't choke writeout for the entire file. > + * For integrity writeback, we must process the entire > + * dirty set regardless of errors because the fs may > + * still have state to clear for each folio. In that > + * case we continue processing and return the first error. > + */ > + if (error == AOP_WRITEPAGE_ACTIVATE) { > + folio_unlock(folio); > + error = 0; Note there really shouldn't be any need for this in outside of the legacy >writepage case. But it might make sense to delay the removal until after ->writepage is gone to avoid bugs in conversions. > + } else if (wbc->sync_mode != WB_SYNC_ALL) { > + wbc->err = error; > + wbc->done_index = folio->index + > + folio_nr_pages(folio); Btw, I wonder if a folio_next_index helper for this might be useful as it's a pattern we have in a few places.