From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C71A83ABD8D for ; Thu, 17 Sep 2026 08:31:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789633875; cv=none; b=cmza8Mc/padRfwJ7+VTp7x7hE6P9rtpIKe2nqpCKhJHcA+SBWhfAt7Jvd+8PeclXHAjaB30skXlgRHHFgJWQ3etnuFXikeR+oVL9vhnp2YqFZWZfpz1k+SFB3WSmLxhQsB+SINHLvSjqi/IE4ajC0W0j5Fn/9cObKyrFwy4GtVA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789633875; c=relaxed/simple; bh=vLEdhgkUC9x/tukFagViGQ7ur/256GYQ1UApjuTIUvo=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=NGpPKaSO+LWTUMOoVgR/xB49ZewLA3D9bcyVORI4S6zUMaPhQcizQ0rkjvjpnlgEZ4ZGLe3bCs3ZcMenOzRoq9LbcFHlB5QZtIFkqayoavUMGmFcI8/YAIXIF7MstMKA/u4lF6yBeeaR3fx1bq353e2enjF4sAqD5Cv1Dg9G+kM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SgqCzWbB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="SgqCzWbB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9E9ED1F000FF; Thu, 17 Sep 2026 08:31:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789633862; bh=lFdpvrBU8kEVcsoKwwf3D1dYac6o7xDt4OTJI4v73rQ=; h=Date:Cc:Subject:To:References:From:In-Reply-To; b=SgqCzWbBDNH2jCl7z1oeAFeSuA8kZQMe7Z3rLtBDqd74tak6GhPOAPioQSJmU6IdZ zFfaZZJTou5qOUd0A3SIS0y5rxt9vP4ewctohpyuI5picascFmUi4tRqy9NQWeQEvS SVBGaq7VCA2wkostOG6qpUSwoF/cI0gvI6g0rADeZLzwrmiDhg+sWnkA1ZxT1Pxrd1 NdwWrXe0+UT80wkw0rwHKPPXKmqlYUPKPmJNoCzrHI3lWfm7yAvRKs0FNlrQYk5Q0P MQpOUec3d2zGlZwm31Mq7mAl326Q6Ji/4Y2qCsGv63FgK+uQPe2yKPoMDO9kmVBcGk PIVui0aWcIgcA== Message-ID: Date: Thu, 17 Sep 2026 16:30:59 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, Barry Song , Juan Yescas , Dev Jain , linux-kernel@vger.kernel.org, David Hildenbrand , Bo Zhang , Kalesh Singh , Nanzhe Zhao , Pengfei Li , Ryan Roberts Subject: Re: [PATCH v2 10/14] f2fs: handle partial truncate of large folio dirty subpages To: Nanzhe Zhao , linux-f2fs-devel@lists.sourceforge.net, Jaegeuk Kim References: <20260915041909.2903887-1-zhaonanzhe@xiaomi.com> <20260915041909.2903887-11-zhaonanzhe@xiaomi.com> Content-Language: en-US From: Chao Yu In-Reply-To: <20260915041909.2903887-11-zhaonanzhe@xiaomi.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/15/26 12:19, Nanzhe Zhao wrote: > A large folio can be partial truncated and stays in folio mapping, we > need to clear the subrange dirty bits and uptodate bits that the partial > truncate covers. If this partial truncate happens to clear the last > subrange dirty bits, then cancel the whole folio dirty state. > > Also add a guard in f2fs_write_single_data_folio() so a large folio > subpage whose disk block was already truncated (NULL_ADDR) is skipped > > Signed-off-by: Nanzhe Zhao > --- > fs/f2fs/data.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 65 insertions(+), 1 deletion(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index d9e3a5c370d7..bf9b9c9b722f 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -2679,6 +2679,34 @@ static void f2fs_ffs_mark_subrange_uptodate(struct folio *folio, size_t offset, > folio_mark_uptodate(folio); > } > > +static void ffs_clear_subrange_uptodate(struct folio *folio, > + size_t offset, size_t len) > +{ > + struct f2fs_folio_state *ffs; > + unsigned int nr_subpages, start, end; > + unsigned long flags; > + > + f2fs_bug_on(F2FS_F_SB(folio), offset + len > folio_size(folio)); > + > + if (!f2fs_folio_has_ffs(folio)) { > + if (folio_test_uptodate(folio)) > + folio_clear_uptodate(folio); > + return; > + } > + > + ffs = (struct f2fs_folio_state *)folio->private; > + nr_subpages = folio_nr_pages(folio); > + start = offset >> PAGE_SHIFT; > + end = (offset + len + PAGE_SIZE - 1) >> PAGE_SHIFT; > + end = min(end, nr_subpages); > + > + spin_lock_irqsave(&ffs->state_lock, flags); > + bitmap_clear(ffs->state, start, end - start); > + spin_unlock_irqrestore(&ffs->state_lock, flags); > + if (folio_test_uptodate(folio)) > + folio_clear_uptodate(folio); > +} > + > bool f2fs_ffs_test_blk_dirty(const struct folio *folio, pgoff_t index) > { > struct f2fs_folio_state *ffs; > @@ -3545,6 +3573,14 @@ static int f2fs_write_single_data_folio(struct folio *folio, int *submitted, > > fio.old_blkaddr = dn.data_blkaddr; > > + /* This page is already truncated */ > + if (fio.old_blkaddr == NULL_ADDR) { > + ffs_clear_subrange_uptodate(folio, > + i << PAGE_SHIFT, PAGE_SIZE); > + folio_clear_f2fs_gcing(folio); Since gcing flag is per-folio, so if block #0 is on gcing, but block #1 is truncated, it will drop on gcing flag of folio, result in triggering IPU on such dirtied block of large folio? also it will affect f2fs_is_cp_guaranteed()? Thanks, > + goto block_done; > + } > + > got_it: > if (__is_valid_data_blkaddr(fio.old_blkaddr) && > !f2fs_is_valid_blkaddr(sbi, fio.old_blkaddr, > @@ -4987,8 +5023,36 @@ void f2fs_invalidate_folio(struct folio *folio, size_t offset, size_t length) > struct f2fs_sb_info *sbi = F2FS_I_SB(inode); > > if (inode->i_ino >= F2FS_ROOT_INO(sbi) && > - (offset || length != folio_size(folio))) > + (offset || length != folio_size(folio))) { > + size_t clear_start = round_up(offset, PAGE_SIZE); > + size_t clear_end = round_down(offset + length, PAGE_SIZE); > + size_t clear_length; > + bool dirty; > + > + /* > + * If the truncated range falls within a single subpage, no > + * subpage state needs to be cleared. > + */ > + if (clear_start >= clear_end || !f2fs_folio_has_ffs(folio)) > + return; > + > + clear_length = clear_end - clear_start; > + dirty = f2fs_ffs_clear_subrange_dirty_and_test(folio, > + clear_start, clear_length); > + ffs_clear_subrange_uptodate(folio, clear_start, clear_length); > + > + /* > + * If the truncated subrange happens to clear the remaining > + * dirty bitmap of the whole folio, cancel the folio-level > + * dirty state. > + */ > + if (!dirty && folio_test_dirty(folio)) { > + inode_dec_dirty_pages(inode); > + f2fs_remove_dirty_inode(inode); > + folio_cancel_dirty(folio); > + } > return; > + } > > if (folio_test_dirty(folio)) { > if (inode->i_ino == F2FS_META_INO(sbi)) {