From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 054BFC07E96 for ; Wed, 7 Jul 2021 00:28:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D578B61CB6 for ; Wed, 7 Jul 2021 00:28:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229998AbhGGAbH (ORCPT ); Tue, 6 Jul 2021 20:31:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:32832 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229834AbhGGAbH (ORCPT ); Tue, 6 Jul 2021 20:31:07 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1C14761CAC; Wed, 7 Jul 2021 00:28:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625617708; bh=lH95/na/HZ5OGpE3O9cwJoBo9Xs9qxACoJL0KKv+lH4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iTiaeRAeIRQP7wvzvJj+DB6GNBBWQE+1ob3ORlrBvxXQkn129HxbcVJ4chxtC1gDX ZcHDjsGruiDoj5LGB4olFGVnYLpzYIC+aj4sh/bOzISEfoPYlj2GopwJRz0wEr+o/s kSzUBr/0lZOl6Sirh1Ysq4i5x76f+okM2X1ZiLVtz8hP5Ru2ZeU4hFBvLk8HO9E5A5 aqTz2+c44C9JCgPnmbBv1nEJQcH8l4yTHmnU3WKMcJ/4/P36lmhXJm9WMh+HlifA4O zwXkt6RlVi+ULtDF81ycNIOKdPoLgV5UAXcCrlIt8VEtX8NU2LWD2e4EwTeKesG7Uj Lzfqwml01jlmQ== Date: Tue, 6 Jul 2021 17:28:27 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Leizhen Subject: Re: [PATCH 1/2] iomap: remove the length variable in iomap_seek_data Message-ID: <20210707002827.GI11588@locust> References: <20210706050541.1974618-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210706050541.1974618-1-hch@lst.de> Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, Jul 06, 2021 at 07:05:40AM +0200, Christoph Hellwig wrote: > The length variable is rather pointless given that it can be trivially > deduced from offset and size. Also the initial calculation can lead > to KASAN warnings. > > Signed-off-by: Christoph Hellwig > Reported-by: Leizhen (ThunderTown) Looks good! Reviewed-by: Darrick J. Wong --D > --- > fs/iomap/seek.c | 16 ++++++---------- > 1 file changed, 6 insertions(+), 10 deletions(-) > > diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c > index dab1b02eba5b7f..50b8f1418f2668 100644 > --- a/fs/iomap/seek.c > +++ b/fs/iomap/seek.c > @@ -83,27 +83,23 @@ loff_t > iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops) > { > loff_t size = i_size_read(inode); > - loff_t length = size - offset; > loff_t ret; > > /* Nothing to be found before or beyond the end of the file. */ > if (offset < 0 || offset >= size) > return -ENXIO; > > - while (length > 0) { > - ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops, - &offset, iomap_seek_data_actor); > + while (offset < size) { > + ret = iomap_apply(inode, offset, size - offset, IOMAP_REPORT, > + ops, &offset, iomap_seek_data_actor); > if (ret < 0) > return ret; > if (ret == 0) > - break; > - > + return offset; > offset += ret; > - length -= ret; > } > > - if (length <= 0) > - return -ENXIO; > - return offset; > + /* We've reached the end of the file without finding data */ > + return -ENXIO; > } > EXPORT_SYMBOL_GPL(iomap_seek_data); > -- > 2.30.2 >