From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 72C051925A3; Tue, 17 Sep 2024 21:29:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726608576; cv=none; b=WNV9EO7rt6XBYHw2u+BCjEciQFA8bMnEQBZYIQ3lXdBRPEDRGLWRYmSJFXCqejTWFzl+6iVI7YgRvOJx8TMCB+uo7Y4xf1Iv6k/fzT6cUpxA/h8EruskoPECyVJaiEGNYIAVTrtRU+1bLA5mXbimHa+RLcTsp0u1tRA0fw3zhU0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726608576; c=relaxed/simple; bh=9oizcgefJXn2A/n2URFPYzu03ElkfcxTmK8MQYXe9xI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=f9se3SKI6v3IbtQ6fQeHUy5jqttIa4JnArl1KXSnZdzK6p2Bw9QpMYUwcqy1bfftShNUWtvHvJW6KApO5VKp5VRCte0oWtuf46PqU/V05Nemmv97OegEM8QZpnDIZM20U6wTwM1tu274GbItDzHVhtqFmhL1dDWM+7nZdTWOZTk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Feq9E+mP; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Feq9E+mP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E1F96C4CED0; Tue, 17 Sep 2024 21:29:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726608576; bh=9oizcgefJXn2A/n2URFPYzu03ElkfcxTmK8MQYXe9xI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Feq9E+mPeDxpS4TNLYUkIkwwYtDQUwUjOdFadPGugiXapB50tsyzfSGkMNrKsRFp6 9ZGqnPHnkcNUF9zBVqi1IDv5AO/pZEUNr2Hys9h0Wtgs/3fJoYTPEMkjhtGYVgf4nh 1VMxBL3gQ2q4QtmrVhj5/lJtgEMcVv2xjtU6qU20AN6/WmsjC5E8YfV+x6MtvN8tVM yj+6G6ata86sw5umXDNwUlR4FoLddeb2yH45B/oenxPcAzWPLRhMLdn9CdsnxxZScC M20WbgK0v6Uq2Qsd6gsopeeo970yIEq1Xvm/FEjSf44CE6aXIh9l3JeKD2oWhkJ+Ri di+kFyUnQoCZw== Date: Tue, 17 Sep 2024 14:29:35 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: Chandan Babu R , Christian Brauner , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 08/12] iomap: zeroing already holds invalidate_lock Message-ID: <20240917212935.GE182177@frogsfrogsfrogs> References: <20240910043949.3481298-1-hch@lst.de> <20240910043949.3481298-9-hch@lst.de> Precedence: bulk X-Mailing-List: linux-xfs@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: <20240910043949.3481298-9-hch@lst.de> On Tue, Sep 10, 2024 at 07:39:10AM +0300, Christoph Hellwig wrote: > All callers of iomap_zero_range already hold invalidate_lock, so we can't > take it again in iomap_file_buffered_write_punch_delalloc. > > Use the passed in flags argument to detect if we're called from a zeroing > operation and don't take the lock again in this case. > > Signed-off-by: Christoph Hellwig > --- > fs/iomap/buffered-io.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c > index 52f285ae4bddcb..3d7e69a542518a 100644 > --- a/fs/iomap/buffered-io.c > +++ b/fs/iomap/buffered-io.c > @@ -1188,8 +1188,13 @@ static void iomap_write_delalloc_release(struct inode *inode, loff_t start_byte, > * folios and dirtying them via ->page_mkwrite whilst we walk the > * cache and perform delalloc extent removal. Failing to do this can > * leave dirty pages with no space reservation in the cache. > + * > + * For zeroing operations the callers already hold invalidate_lock. > */ > - filemap_invalidate_lock(inode->i_mapping); > + if (flags & IOMAP_ZERO) > + rwsem_assert_held_write(&inode->i_mapping->invalidate_lock); Does the other iomap_zero_range user (gfs2) take the invalidate lock? AFAICT it doesn't. Shouldn't we annotate iomap_zero_range to say that callers have to hold i_rwsem and the invalidate_lock? --D > + else > + filemap_invalidate_lock(inode->i_mapping); > while (start_byte < scan_end_byte) { > loff_t data_end; > > @@ -1240,7 +1245,8 @@ static void iomap_write_delalloc_release(struct inode *inode, loff_t start_byte, > punch(inode, punch_start_byte, end_byte - punch_start_byte, > iomap); > out_unlock: > - filemap_invalidate_unlock(inode->i_mapping); > + if (!(flags & IOMAP_ZERO)) > + filemap_invalidate_unlock(inode->i_mapping); > } > > /* > -- > 2.45.2 > >