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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8AA3AC433EF for ; Mon, 20 Jun 2022 12:19:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240840AbiFTMTv (ORCPT ); Mon, 20 Jun 2022 08:19:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37694 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240101AbiFTMTt (ORCPT ); Mon, 20 Jun 2022 08:19:49 -0400 Received: from out30-57.freemail.mail.aliyun.com (out30-57.freemail.mail.aliyun.com [115.124.30.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5ABDF63FF for ; Mon, 20 Jun 2022 05:19:48 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R901e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046050;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0VGx.DGq_1655727584; Received: from B-P7TQMD6M-0146.local(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0VGx.DGq_1655727584) by smtp.aliyun-inc.com; Mon, 20 Jun 2022 20:19:45 +0800 Date: Mon, 20 Jun 2022 20:19:44 +0800 From: Gao Xiang To: hongnanLi Cc: Chao Yu , linux-erofs@lists.ozlabs.org, xiang@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] erofs: update ctx->pos for every emitted dirent Message-ID: References: <20220527072536.68516-1-hongnan.li@linux.alibaba.com> <20220609034006.76649-1-hongnan.li@linux.alibaba.com> <0c139517-e976-5017-8e7a-d34c38f0f6bb@kernel.org> <70fe93a3-7af5-b563-dcb7-3f7be81348ed@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <70fe93a3-7af5-b563-dcb7-3f7be81348ed@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Hongnan, On Mon, Jun 20, 2022 at 05:37:07PM +0800, hongnanLi wrote: > on 2022/6/19 8:19, Chao Yu wrote: > > On 2022/6/9 11:40, Hongnan Li wrote: > > > erofs_readdir update ctx->pos after filling a batch of dentries > > > and it may cause dir/files duplication for NFS readdirplus which > > > depends on ctx->pos to fill dir correctly. So update ctx->pos for > > > every emitted dirent in erofs_fill_dentries to fix it. > > > > > > Fixes: 3e917cc305c6 ("erofs: make filesystem exportable") > > > Signed-off-by: Hongnan Li > > > --- > > >   fs/erofs/dir.c | 20 ++++++++++---------- > > >   1 file changed, 10 insertions(+), 10 deletions(-) > > > > > > diff --git a/fs/erofs/dir.c b/fs/erofs/dir.c > > > index 18e59821c597..94ef5287237a 100644 > > > --- a/fs/erofs/dir.c > > > +++ b/fs/erofs/dir.c > > > @@ -22,10 +22,9 @@ static void debug_one_dentry(unsigned char > > > d_type, const char *de_name, > > >   } > > >   static int erofs_fill_dentries(struct inode *dir, struct > > > dir_context *ctx, > > > -                   void *dentry_blk, unsigned int *ofs, > > > +                   void *dentry_blk, struct erofs_dirent *de, > > >                      unsigned int nameoff, unsigned int maxsize) > > >   { > > > -    struct erofs_dirent *de = dentry_blk + *ofs; > > >       const struct erofs_dirent *end = dentry_blk + nameoff; > > >       while (de < end) { > > > @@ -59,9 +58,8 @@ static int erofs_fill_dentries(struct inode *dir, > > > struct dir_context *ctx, > > >               /* stopped by some reason */ > > >               return 1; > > >           ++de; > > > -        *ofs += sizeof(struct erofs_dirent); > > > +        ctx->pos += sizeof(struct erofs_dirent); > > >       } > > > -    *ofs = maxsize; > > >       return 0; > > >   } > > > @@ -95,7 +93,7 @@ static int erofs_readdir(struct file *f, struct > > > dir_context *ctx) > > >                     "invalid de[0].nameoff %u @ nid %llu", > > >                     nameoff, EROFS_I(dir)->nid); > > >               err = -EFSCORRUPTED; > > > -            goto skip_this; > > > +            break; > > >           } > > >           maxsize = min_t(unsigned int, > > > @@ -106,17 +104,19 @@ static int erofs_readdir(struct file *f, > > > struct dir_context *ctx) > > >               initial = false; > > >               ofs = roundup(ofs, sizeof(struct erofs_dirent)); > > > -            if (ofs >= nameoff) > > > +            if (ofs >= nameoff) { > > > +                ctx->pos = blknr_to_addr(i) + ofs; > > >                   goto skip_this; > > > +            } > > >           } > > > -        err = erofs_fill_dentries(dir, ctx, de, &ofs, > > > -                      nameoff, maxsize); > > > -skip_this: > > >           ctx->pos = blknr_to_addr(i) + ofs; > > > > Why updating ctx->pos before erofs_fill_dentries()? > > > > Thanks, > > It’s to ensure the ctx->pos is correct and up to date in > erofs_fill_dentries() so that we can update ctx->pos instead of ofs for > every emitted dirent. > How about this, since blknr_to_addr(i) + maxsize should be the start of the next dir block. if (initial) { ofs = roundup(ofs, sizeof(struct erofs_dirent)); ctx->pos = blknr_to_addr(i) + ofs; if (ofs >= nameoff) goto skip_this; } err = erofs_fill_dentries(dir, ctx, de, (void *)de + ofs, nameoff, maxsize); if (err) break; ctx->pos = blknr_to_addr(i) + maxsize; Thanks, Gao Xiang 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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 40389C43334 for ; Mon, 20 Jun 2022 12:20:12 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4LRTHZ30gxz3bvP for ; Mon, 20 Jun 2022 22:20:10 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.56; helo=out30-56.freemail.mail.aliyun.com; envelope-from=hsiangkao@linux.alibaba.com; receiver=) Received: from out30-56.freemail.mail.aliyun.com (out30-56.freemail.mail.aliyun.com [115.124.30.56]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4LRTHR1Cwbz3blT for ; Mon, 20 Jun 2022 22:20:00 +1000 (AEST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R901e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046050;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0VGx.DGq_1655727584; Received: from B-P7TQMD6M-0146.local(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0VGx.DGq_1655727584) by smtp.aliyun-inc.com; Mon, 20 Jun 2022 20:19:45 +0800 Date: Mon, 20 Jun 2022 20:19:44 +0800 From: Gao Xiang To: hongnanLi Subject: Re: [PATCH v2] erofs: update ctx->pos for every emitted dirent Message-ID: References: <20220527072536.68516-1-hongnan.li@linux.alibaba.com> <20220609034006.76649-1-hongnan.li@linux.alibaba.com> <0c139517-e976-5017-8e7a-d34c38f0f6bb@kernel.org> <70fe93a3-7af5-b563-dcb7-3f7be81348ed@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <70fe93a3-7af5-b563-dcb7-3f7be81348ed@linux.alibaba.com> X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" Hi Hongnan, On Mon, Jun 20, 2022 at 05:37:07PM +0800, hongnanLi wrote: > on 2022/6/19 8:19, Chao Yu wrote: > > On 2022/6/9 11:40, Hongnan Li wrote: > > > erofs_readdir update ctx->pos after filling a batch of dentries > > > and it may cause dir/files duplication for NFS readdirplus which > > > depends on ctx->pos to fill dir correctly. So update ctx->pos for > > > every emitted dirent in erofs_fill_dentries to fix it. > > > > > > Fixes: 3e917cc305c6 ("erofs: make filesystem exportable") > > > Signed-off-by: Hongnan Li > > > --- > > >   fs/erofs/dir.c | 20 ++++++++++---------- > > >   1 file changed, 10 insertions(+), 10 deletions(-) > > > > > > diff --git a/fs/erofs/dir.c b/fs/erofs/dir.c > > > index 18e59821c597..94ef5287237a 100644 > > > --- a/fs/erofs/dir.c > > > +++ b/fs/erofs/dir.c > > > @@ -22,10 +22,9 @@ static void debug_one_dentry(unsigned char > > > d_type, const char *de_name, > > >   } > > >   static int erofs_fill_dentries(struct inode *dir, struct > > > dir_context *ctx, > > > -                   void *dentry_blk, unsigned int *ofs, > > > +                   void *dentry_blk, struct erofs_dirent *de, > > >                      unsigned int nameoff, unsigned int maxsize) > > >   { > > > -    struct erofs_dirent *de = dentry_blk + *ofs; > > >       const struct erofs_dirent *end = dentry_blk + nameoff; > > >       while (de < end) { > > > @@ -59,9 +58,8 @@ static int erofs_fill_dentries(struct inode *dir, > > > struct dir_context *ctx, > > >               /* stopped by some reason */ > > >               return 1; > > >           ++de; > > > -        *ofs += sizeof(struct erofs_dirent); > > > +        ctx->pos += sizeof(struct erofs_dirent); > > >       } > > > -    *ofs = maxsize; > > >       return 0; > > >   } > > > @@ -95,7 +93,7 @@ static int erofs_readdir(struct file *f, struct > > > dir_context *ctx) > > >                     "invalid de[0].nameoff %u @ nid %llu", > > >                     nameoff, EROFS_I(dir)->nid); > > >               err = -EFSCORRUPTED; > > > -            goto skip_this; > > > +            break; > > >           } > > >           maxsize = min_t(unsigned int, > > > @@ -106,17 +104,19 @@ static int erofs_readdir(struct file *f, > > > struct dir_context *ctx) > > >               initial = false; > > >               ofs = roundup(ofs, sizeof(struct erofs_dirent)); > > > -            if (ofs >= nameoff) > > > +            if (ofs >= nameoff) { > > > +                ctx->pos = blknr_to_addr(i) + ofs; > > >                   goto skip_this; > > > +            } > > >           } > > > -        err = erofs_fill_dentries(dir, ctx, de, &ofs, > > > -                      nameoff, maxsize); > > > -skip_this: > > >           ctx->pos = blknr_to_addr(i) + ofs; > > > > Why updating ctx->pos before erofs_fill_dentries()? > > > > Thanks, > > It’s to ensure the ctx->pos is correct and up to date in > erofs_fill_dentries() so that we can update ctx->pos instead of ofs for > every emitted dirent. > How about this, since blknr_to_addr(i) + maxsize should be the start of the next dir block. if (initial) { ofs = roundup(ofs, sizeof(struct erofs_dirent)); ctx->pos = blknr_to_addr(i) + ofs; if (ofs >= nameoff) goto skip_this; } err = erofs_fill_dentries(dir, ctx, de, (void *)de + ofs, nameoff, maxsize); if (err) break; ctx->pos = blknr_to_addr(i) + maxsize; Thanks, Gao Xiang