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 77E43C77B70 for ; Fri, 14 Apr 2023 07:21:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229464AbjDNHVV (ORCPT ); Fri, 14 Apr 2023 03:21:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229446AbjDNHVV (ORCPT ); Fri, 14 Apr 2023 03:21:21 -0400 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94EB14C06 for ; Fri, 14 Apr 2023 00:21:19 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R171e4;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=4;SR=0;TI=SMTPD_---0Vg2fApy_1681456876; Received: from 30.97.49.1(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0Vg2fApy_1681456876) by smtp.aliyun-inc.com; Fri, 14 Apr 2023 15:21:16 +0800 Message-ID: Date: Fri, 14 Apr 2023 15:21:15 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.9.1 Subject: Re: [PATCH 1/7] ovl: update of dentry revalidate flags after copy up To: Amir Goldstein , Miklos Szeredi Cc: Alexander Larsson , linux-unionfs@vger.kernel.org References: <20230408164302.1392694-1-amir73il@gmail.com> <20230408164302.1392694-2-amir73il@gmail.com> From: Gao Xiang In-Reply-To: <20230408164302.1392694-2-amir73il@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-unionfs@vger.kernel.org On 2023/4/9 00:42, Amir Goldstein wrote: > After copy up, we may need to update d_flags if upper dentry is on a > remote fs and lower dentries are not. > > Add helpers to allow incremental update of the revalidate flags. > > Fixes: bccece1ead36 ("ovl: allow remote upper") > Signed-off-by: Amir Goldstein Reviewed-by: Gao Xiang > --- > fs/overlayfs/copy_up.c | 2 ++ > fs/overlayfs/dir.c | 3 +-- > fs/overlayfs/export.c | 3 +-- > fs/overlayfs/namei.c | 3 +-- > fs/overlayfs/overlayfs.h | 6 ++++-- > fs/overlayfs/super.c | 2 +- > fs/overlayfs/util.c | 24 ++++++++++++++++++++---- > 7 files changed, 30 insertions(+), 13 deletions(-) > > diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c > index c14e90764e35..7bf101e756c8 100644 > --- a/fs/overlayfs/copy_up.c > +++ b/fs/overlayfs/copy_up.c > @@ -576,6 +576,7 @@ static int ovl_link_up(struct ovl_copy_up_ctx *c) > /* Restore timestamps on parent (best effort) */ > ovl_set_timestamps(ofs, upperdir, &c->pstat); > ovl_dentry_set_upper_alias(c->dentry); > + ovl_dentry_update_reval(c->dentry, upper); > } > } > inode_unlock(udir); > @@ -895,6 +896,7 @@ static int ovl_do_copy_up(struct ovl_copy_up_ctx *c) > inode_unlock(udir); > > ovl_dentry_set_upper_alias(c->dentry); > + ovl_dentry_update_reval(c->dentry, ovl_dentry_upper(c->dentry)); > } > > out: > diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c > index fc25fb95d5fc..9be52d8013c8 100644 > --- a/fs/overlayfs/dir.c > +++ b/fs/overlayfs/dir.c > @@ -269,8 +269,7 @@ static int ovl_instantiate(struct dentry *dentry, struct inode *inode, > > ovl_dir_modified(dentry->d_parent, false); > ovl_dentry_set_upper_alias(dentry); > - ovl_dentry_update_reval(dentry, newdentry, > - DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE); > + ovl_dentry_init_reval(dentry, newdentry); > > if (!hardlink) { > /* > diff --git a/fs/overlayfs/export.c b/fs/overlayfs/export.c > index defd4e231ad2..5c36fb3a7bab 100644 > --- a/fs/overlayfs/export.c > +++ b/fs/overlayfs/export.c > @@ -326,8 +326,7 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb, > if (upper_alias) > ovl_dentry_set_upper_alias(dentry); > > - ovl_dentry_update_reval(dentry, upper, > - DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE); > + ovl_dentry_init_reval(dentry, upper); > > return d_instantiate_anon(dentry, inode); > > diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c > index cfb3420b7df0..100a492d2b2a 100644 > --- a/fs/overlayfs/namei.c > +++ b/fs/overlayfs/namei.c > @@ -1122,8 +1122,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, > ovl_set_flag(OVL_UPPERDATA, inode); > } > > - ovl_dentry_update_reval(dentry, upperdentry, > - DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE); > + ovl_dentry_init_reval(dentry, upperdentry); > > revert_creds(old_cred); > if (origin_path) { > diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h > index 4d0b278f5630..e100c55bb924 100644 > --- a/fs/overlayfs/overlayfs.h > +++ b/fs/overlayfs/overlayfs.h > @@ -375,8 +375,10 @@ bool ovl_index_all(struct super_block *sb); > bool ovl_verify_lower(struct super_block *sb); > struct ovl_entry *ovl_alloc_entry(unsigned int numlower); > bool ovl_dentry_remote(struct dentry *dentry); > -void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *upperdentry, > - unsigned int mask); > +void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry); > +void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry); > +void ovl_dentry_init_flags(struct dentry *dentry, struct dentry *upperdentry, > + unsigned int mask); > bool ovl_dentry_weird(struct dentry *dentry); > enum ovl_path_type ovl_path_type(struct dentry *dentry); > void ovl_path_upper(struct dentry *dentry, struct path *path); > diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c > index f1d9f75f8786..49b6956468f9 100644 > --- a/fs/overlayfs/super.c > +++ b/fs/overlayfs/super.c > @@ -1885,7 +1885,7 @@ static struct dentry *ovl_get_root(struct super_block *sb, > ovl_dentry_set_flag(OVL_E_CONNECTED, root); > ovl_set_upperdata(d_inode(root)); > ovl_inode_init(d_inode(root), &oip, ino, fsid); > - ovl_dentry_update_reval(root, upperdentry, DCACHE_OP_WEAK_REVALIDATE); > + ovl_dentry_init_flags(root, upperdentry, DCACHE_OP_WEAK_REVALIDATE); > > return root; > } > diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c > index 923d66d131c1..6a0652bd51f2 100644 > --- a/fs/overlayfs/util.c > +++ b/fs/overlayfs/util.c > @@ -94,14 +94,30 @@ struct ovl_entry *ovl_alloc_entry(unsigned int numlower) > return oe; > } > > +#define OVL_D_REVALIDATE (DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE) > + > bool ovl_dentry_remote(struct dentry *dentry) > { > - return dentry->d_flags & > - (DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE); > + return dentry->d_flags & OVL_D_REVALIDATE; > +} > + > +void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry) > +{ > + if (!ovl_dentry_remote(realdentry)) > + return; > + > + spin_lock(&dentry->d_lock); > + dentry->d_flags |= realdentry->d_flags & OVL_D_REVALIDATE; Although I'm not sure if it could cause some lazy awareness due to dcache RCU-walk, but maybe that is fine since such window is small? Thanks, Gao Xiang