From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp02-ext3.udag.de (smtp02-ext3.udag.de [62.146.106.33]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E1318194AD7; Wed, 14 Jan 2026 08:58:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.146.106.33 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768381117; cv=none; b=pxS5S+qrJDc8Vlb+lNJT3lPS+SDOcWHuih+WW63qffPr4W2x7jxFsXRR7ivLat/vpOBkH+/zC+bbfK+jBrj645/mD8Kz34PD93g6MQPt4TISsp/kATP/w4qbEclcMdq07Jzp0SYRZD17m1HO+iMzIeN5/ohnnCsCOzsC00jEmBE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768381117; c=relaxed/simple; bh=n6GOFMrndcTCYHv9NVk1Fnmc+p05mBnVXmgbVDedAl4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EzkS7IMq/pIOJRMQtYy85e+VpHk1Qc82y0jn7XLccw1GCOqMsoG8MTko1eT3GAkwYKwJVEeZnEKCMehyXT2cV4+E0OVnx4V1cjUTirigRJIG4pQ9uHCrYrUzQXfLQXbOf5oEYpYPNoIm1ZyrvjzwBxJvlhNEDDL3jdr8zevAFoM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=birthelmer.de; spf=pass smtp.mailfrom=birthelmer.de; arc=none smtp.client-ip=62.146.106.33 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=birthelmer.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=birthelmer.de Received: from localhost (200-143-067-156.ip-addr.inexio.net [156.67.143.200]) by smtp02-ext3.udag.de (Postfix) with ESMTPA id 38F83E0267; Wed, 14 Jan 2026 09:58:23 +0100 (CET) Authentication-Results: smtp02-ext3.udag.de; auth=pass smtp.auth=birthelmercom-0001 smtp.mailfrom=horst@birthelmer.de Date: Wed, 14 Jan 2026 09:58:22 +0100 From: Horst Birthelmer To: Jingbo Xu Cc: miklos@szeredi.hu, joannelkoong@gmail.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ak: fuse: fix premature writetrhough request for large folio Message-ID: References: <20260114055615.17903-1-jefflexu@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260114055615.17903-1-jefflexu@linux.alibaba.com> Hi Jingbo, On Wed, Jan 14, 2026 at 01:56:15PM +0800, Jingbo Xu wrote: > When large folio is enabled and the initial folio offset exceeds > PAGE_SIZE, e.g. the position resides in the second page of a large > folio, after the folio copying the offset (in the page) won't be updated > to 0 even though the expected range is successfully copied until the end > of the folio. In this case fuse_fill_write_pages() exits prematurelly > before the request has reached the max_write/max_pages limit. > > Fix this by eliminating page offset entirely and use folio offset > instead. > > Fixes: d60a6015e1a2 ("fuse: support large folios for writethrough writes") > Cc: stable@vger.kernel.org > Signed-off-by: Jingbo Xu > --- > fs/fuse/file.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/fs/fuse/file.c b/fs/fuse/file.c > index 625d236b881b..6aafb32338b6 100644 > --- a/fs/fuse/file.c > +++ b/fs/fuse/file.c > @@ -1272,7 +1272,6 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia, > { > struct fuse_args_pages *ap = &ia->ap; > struct fuse_conn *fc = get_fuse_conn(mapping->host); > - unsigned offset = pos & (PAGE_SIZE - 1); > size_t count = 0; > unsigned int num; > int err = 0; > @@ -1299,7 +1298,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia, > if (mapping_writably_mapped(mapping)) > flush_dcache_folio(folio); > > - folio_offset = ((index - folio->index) << PAGE_SHIFT) + offset; > + folio_offset = offset_in_folio(folio, pos); > bytes = min(folio_size(folio) - folio_offset, num); > > tmp = copy_folio_from_iter_atomic(folio, folio_offset, bytes, ii); > @@ -1329,9 +1328,6 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia, > count += tmp; > pos += tmp; > num -= tmp; > - offset += tmp; > - if (offset == folio_size(folio)) > - offset = 0; > > /* If we copied full folio, mark it uptodate */ > if (tmp == folio_size(folio)) > @@ -1343,7 +1339,9 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia, > ia->write.folio_locked = true; > break; > } > - if (!fc->big_writes || offset != 0) > + if (!fc->big_writes) > + break; > + if (folio_offset + tmp != folio_size(folio)) > break; > } > > -- > 2.19.1.6.gb485710b > > I think this might have been an oversight when moving from pages to folios. Reviewed-by: Horst Birthelmer