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[2620:137:e000::1:20]) by mx.google.com with ESMTP id 3-20020a630003000000b004119e27a4d2si2491599pga.507.2022.08.12.07.46.54; Fri, 12 Aug 2022 07:47:09 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20210112 header.b=PjBoEWCW; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238856AbiHLOg5 (ORCPT + 99 others); Fri, 12 Aug 2022 10:36:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58260 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238816AbiHLOgx (ORCPT ); Fri, 12 Aug 2022 10:36:53 -0400 Received: from mail-oi1-x22e.google.com (mail-oi1-x22e.google.com [IPv6:2607:f8b0:4864:20::22e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D83CA85AAB; Fri, 12 Aug 2022 07:36:50 -0700 (PDT) Received: by mail-oi1-x22e.google.com with SMTP id u14so1352033oie.2; Fri, 12 Aug 2022 07:36:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc; bh=aLNxAW8k/19aq8D5p21jQUroC1e8wOaHHjI3tUSg7Ug=; b=PjBoEWCWr/syZR311IaxNV7cmyWntmhJtWnSzcRcoz++dD2f0iW5sYGmbUt9qSl916 vZ04rprhghoi3cu0uVEmXHsz8GniijvmbiIA+4runp2JXDjcHl7Q7YehdJyjYkMWLOF3 qiQ51E8E4xGHOzBf4I2qWJLAaxOrWLUSZpyBDpg0vdGznDHVnwrO9pRT/7HDpF6eKVlP JhbaeYW0DGZKDLYHmX5ayi2JrBxV/Nd8OiZXzTeH+0UiCDhuRQ3YTejrJp5NVtUbzhGd yjMMzPMDqTEQNE8ZR+vrcq/6eXnuiVFqmjuJaXc9QkBDNtMyW+5VSphWuLEnEVJmu+2b x1aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc; bh=aLNxAW8k/19aq8D5p21jQUroC1e8wOaHHjI3tUSg7Ug=; b=Jo6lUrJwsdmTna3G71lyUo9FAM4mwygc6FZIgnITGjSAaYlSfh7TktQYZip7tdLOOM RFUXvgItf3+PT8xnnrKJKoDVWRC9Lm75mR5kJrvBYiE9XhOt5cyqaa6FoWgTyTAnapOG MkoDJV5RtR3TqoE+ITByymPP8BQIuVej0VEpBCWBV3s1JUt5mMk5Tv2RegeiFaqq15pB /Fm+dFYbGJHYtvm8oXInVCwaMPSt0wkiSXHAuD8z2YkNw1V0yomceeL0zgP/VoRNcfgV RqDG+eLRVOlZXZsRfI5IWJ9n72C9mkSjIXQ7yvwz4+hlUX/5zjAFFxsssIsKlXDKkIVr fkjQ== X-Gm-Message-State: ACgBeo1Ia5/uiZix5GVltPsVOJL/U5KzolY00UkVk177jBXjud50Ohvv T5B4ENVR7mz2OOfC8RyNwZNtR7vH9gwC7J4JAfI= X-Received: by 2002:a05:6808:6da:b0:342:cf1e:45be with SMTP id m26-20020a05680806da00b00342cf1e45bemr5558490oih.138.1660315009788; Fri, 12 Aug 2022 07:36:49 -0700 (PDT) MIME-Version: 1.0 References: <20220811100912.126447-1-bingjingc@synology.com> <20220811100912.126447-3-bingjingc@synology.com> In-Reply-To: From: bingjing chang Date: Fri, 12 Aug 2022 22:36:38 +0800 Message-ID: Subject: Re: [PATCH v2 2/2] btrfs: send: fix failures when processing inodes with no links To: Filipe Manana Cc: bingjingc , Josef Bacik , David Sterba , Chris Mason , linux-btrfs , Linux Kernel Mailing List , Robbie Ko , stable@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=0.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, FROM_LOCAL_NOVOWEL,HK_RANDOM_ENVFROM,HK_RANDOM_FROM,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Filipe Manana =E6=96=BC 2022=E5=B9=B48=E6=9C=8811=E6= =97=A5 =E9=80=B1=E5=9B=9B =E6=99=9A=E4=B8=8A8:00=E5=AF=AB=E9=81=93=EF=BC=9A > > On Thu, Aug 11, 2022 at 11:09 AM bingjingc wrote= : > > > > From: BingJing Chang > > > > There is a bug causing send failures when processing an orphan director= y > > with no links. In commit 46b2f4590aab ("Btrfs: fix send failure when ro= ot > > has deleted files still open")', the orphan inode issue was addressed. = The > > send operation fails with a ENOENT error because of any attempts to > > generate a path for the inode with a link count of zero. Therefore, in = that > > patch, sctx->ignore_cur_inode was introduced to be set if the current i= node > > has a link count of zero for bypassing some unnecessary steps. And a he= lper > > function btrfs_unlink_all_paths() was introduced and called to clean up= old > > paths found in the parent snapshot. However, not only regular files but > > also directories can be orphan inodes. So if the send operation meets a= n > > orphan directory, it will issue a wrong unlink command for that directo= ry > > now. Soon the receive operation fails with a EISDIR error. Besides, the > > send operation also fails with a ENOENT error later when it tries to > > generate a path of it. > > > > Similar example but making an orphan dir for an incremental send: > > > > $ btrfs subvolume create vol > > $ mkdir vol/dir > > $ touch vol/dir/foo > > > > $ btrfs subvolume snapshot -r vol snap1 > > $ btrfs subvolume snapshot -r vol snap2 > > > > # Turn the second snapshot to RW mode and delete the whole dir while > > # holding an open file descriptor on it. > > $ btrfs property set snap2 ro false > > $ exec 73 > $ rm -rf snap2/dir > > > > # Set the second snapshot back to RO mode and do an incremental send. > > $ btrfs property set snap2 ro true > > $ mkdir receive_dir > > $ btrfs send snap2 -p snap1 | btrfs receive receive_dir/ > > At subvol snap2 > > At snapshot snap2 > > ERROR: send ioctl failed with -2: No such file or directory > > ERROR: unlink dir failed. Is a directory > > > > Actually, orphan inodes are more common use cases in cascading backups. > > (Please see the illustration below.) In a cascading backup, a user want= s > > to replicate a couple of snapshots from Machine A to Machine B and from > > Machine B to Machine C. Machine B doesn't take any RO snapshots for > > sending. All a receiver does is create an RW snapshot of its parent > > snapshot, apply the send stream and turn it into RO mode at the end. Ev= en > > if all paths of some inodes are deleted in applying the send stream, th= ese > > inodes would not be deleted and become orphans after changing the subvo= lume > > from RW to RO. Moreover, orphan inodes can occur not only in send snaps= hots > > but also in parent snapshots because Machine B may do a batch replicati= on > > of a couple of snapshots. > > > > An illustration for cascading backups: > > Machine A (snapshot {1..n}) --> Machine B --> Machine C > > > > The intuition to solve the problem is to delete all the items of orphan > > inodes before using these snapshots for sending. I used to think that t= he > > reasonable timing for doing that is during the ioctl of changing the > > subvolume from RW to RO because it sounds good that we will not modify = the > > fs tree of a RO snapshot anymore. However, attempting to do the orphan > > cleanup in the ioctl would be pointless. Because if someone is holding = an > > open file descriptor on the inode, the reference count of the inode wil= l > > never drop to 0. Then iput() cannot trigger eviction, which finally del= etes > > all the items of it. So we try to extend the original patch to handle > > orphans in send/parent snapshots. Here are several cases that need to b= e > > considered: > > > > Case 1: BTRFS_COMPARE_TREE_NEW > > | send snapshot | action > > -------------------------------- > > nlink | 0 | ignore > > > > In case 1, when we get a BTRFS_COMPARE_TREE_NEW tree comparison result, > > it means that a new inode is found in the send snapshot and it doesn't > > appear in the parent snapshot. Since this inode has a link count of zer= o > > (It's an orphan and there're no paths for it.), we can leverage > > sctx->ignore_cur_inode in the original patch to prevent it from being > > created. > > > > Case 2: BTRFS_COMPARE_TREE_DELETED > > | parent snapshot | action > > ---------------------------------- > > nlink | 0 | as usual > > > > In case 2, when we get a BTRFS_COMPARE_TREE_DELETED tree comparison > > result, it means that the inode only appears in the parent snapshot. > > As usual, the send operation will try to delete all its paths. However, > > this inode has a link count of zero, so no paths of it will be found. N= o > > deletion operations will be issued. We don't need to change any logic. > > > > Case 3: BTRFS_COMPARE_TREE_CHANGED > > | | parent snapshot | send snapshot | action > > ----------------------------------------------------------------------= - > > subcase 1 | nlink | 0 | 0 | ignore > > subcase 2 | nlink | >0 | 0 | new_gen(deletion= ) > > subcase 3 | nlink | 0 | >0 | new_gen(creation= ) > > > > In case 3, when we get a BTRFS_COMPARE_TREE_CHANGED tree comparison res= ult, > > it means that the inode appears in both snapshots. Here're three subcas= es. > > > > First, if the inode has link counts of zero in both snapshots. Since th= ere > > are no paths for this inode in (source/destination) parent snapshots an= d we > > don't care about whether there is also an orphan inode in destination o= r > > not, we can set sctx->ignore_cur_inode on to prevent it from being crea= ted. > > > > For the second and the third subcases, if there're paths in one snapsho= t > > and there're no paths in the other snapshot for this inode. We can trea= t > > this inode as a new generation. We can also leverage the logic handling= a > > new generation of an inode with small adjustments. Then it will delete = all > > old paths and create a new inode with new attributes and paths only whe= n > > there's a positive link count in the send snapshot. In subcase 2, the > > send operation only needs to delete all old paths as in the parent > > snapshot. But it may require more operations for a directory to remove = its > > old paths. If a not-empty directory is going to be deleted (because it = has > > a link count of zero in the send snapshot) but there're files/directori= es > > with bigger inode numbers under it, the send operation will need to ren= ame > > it to its orphan name first. After processing and deleting the last ite= m > > under this directory, the send operation will check this directory, aka > > the parent directory of the last item, again and issue a rmdir operatio= n > > to remove it finally. Therefore, we also need to treat inodes with a li= nk > > count of zero as if they didn't exist in get_cur_inode_state(), which i= s > > used in process_recorded_refs(). By doing this, when reviewing a direct= ory > > with orphan names after the last item under it has been deleted, the se= nd > > operation now can properly issue a rmdir operation. Otherwise, without > > doing this, the orphan directory with an orphan name would be kept here > > at the end due to the existing inode with a link count of zero being fo= und. > > In subcase 3, as in case 2, no old paths would be found, so no deletion > > operations will be issued. The send operation will only create a new on= e > > for that inode. > > > > Note that subcase 3 is not a common case. That's because it's easy to > > reduce the hard links of an inode, but once all valid paths are removed= , > > there're no valid paths for creating other hard links. The only way to = do > > that is trying to send an older snapshot after a newer snapshot has bee= n > > sent. > > > > Cc: # 4.9: 46b2f4590aab: Btrfs: fix send > > failure when root has deleted files still open > > Cc: # 4.9: 71ecfc133b03: btrfs: send: > > introduce recorded_ref_alloc and recorded_ref_free > > Cc: # 4.9: 3aa5bd367fa5: btrfs: send: fix > > sending link commands for existing file paths > > Cc: # 4.9: 0d8869fb6b6f8: btrfs: send: always > > use the rbtree based inode ref management infrastructure > > Btw, lines with CC, Fixes, etc, tags should not be broken even if they > are wider than 74 characters. > Okay, thank you for telling me that. > So, in v1 when I gave you that example of CC stable tags, it wasn't > meant for you to literally copy-paste them. > > First I asked if the purpose of the original Fixes tag was to backport > the fix to stable releases. > Was that the intention? You didn't provide an answer about that. > Oh, I misunderstood your suggestion. I'm sorry about that. Our intention is to report this bug and try to provide a reasonable and acceptable fix for it. Backporting is not our goal. > Then I told if that was the case, the proper way would be adding CC > stable tags and listing any > dependencies. I gave those 4 as examples with commits that are fairly > recent and obvious dependencies, > but I also said that probably there's a lot more missing - especially > if we want to backport to as far as 4.9. > > Even with just those 4 dependencies, some of those commits are fairly > large, and that may be frowned upon > according to stable backport rules (listed at > https://www.kernel.org/doc/Documentation/process/stable-kernel-rules.rst)= . > For e.g., patches with over 100 lines changed. > > Now, did you actually verify if there were more dependencies? (and test) > And do you really want to go as far as 4.9 (currently the oldest > stable release)? No, I didn't. I used to think the CC tag was a very cool feature, which just putting a few commits lets backport easily when I read your mail, so I copied and pasted these 4 commits in the beginning of revising the patch v2. However, I'm wrong. > I seriously doubt that those 4 commits are the only dependencies in > order to be able to cleanly backport to 4.9 and other old branches. > > It may be better to backport only to a few younger stable branches, or > just provide later a version of the patch to > apply to each desired stable branch (once the fix is in Linus' tree > and in a -rc release). > > If you are not interested in backporting to stable or don't have the > time to verify the dependencies and test, then just remove all the > stable tags. > Just leave a fixes tag: > > Fixes: 31db9f7c23fbf7 ("Btrfs: introduce BTRFS_IOC_SEND for btrfs send/re= ceive") > Since backporting is not our goal. I will just leave the fix tag here. > Also, please don't forget to send a test case for fstests, covering as > many cases as possible (not just the example > at the beginning of the changelog). > Okay, I will submit a test case covering all cases. Because I still need to spend time learning how to use the fssum utility for the last test case you reviewed, so I will submit the test case later. Thanks. > Thanks. > > > Reviewed-by: Robbie Ko > > Signed-off-by: BingJing Chang > > --- > > fs/btrfs/send.c | 214 +++++++++++++++++++----------------------------- > > 1 file changed, 85 insertions(+), 129 deletions(-) > > > > diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c > > index f8d77a33b9b7..6ab1ba66ff4b 100644 > > --- a/fs/btrfs/send.c > > +++ b/fs/btrfs/send.c > > @@ -850,6 +850,7 @@ struct btrfs_inode_info { > > u64 gid; > > u64 rdev; > > u64 attr; > > + u64 nlink; > > }; > > > > /* > > @@ -888,6 +889,7 @@ static int get_inode_info(struct btrfs_root *root, = u64 ino, > > info->uid =3D btrfs_inode_uid(path->nodes[0], ii); > > info->gid =3D btrfs_inode_gid(path->nodes[0], ii); > > info->rdev =3D btrfs_inode_rdev(path->nodes[0], ii); > > + info->nlink =3D btrfs_inode_nlink(path->nodes[0], ii); > > /* > > * Transfer the unchanged u64 value of btrfs_inode_item::flags,= that's > > * otherwise logically split to 32/32 parts. > > @@ -1652,19 +1654,22 @@ static int get_cur_inode_state(struct send_ctx = *sctx, u64 ino, u64 gen) > > int right_ret; > > u64 left_gen; > > u64 right_gen; > > + struct btrfs_inode_info info; > > > > - ret =3D get_inode_gen(sctx->send_root, ino, &left_gen); > > + ret =3D get_inode_info(sctx->send_root, ino, &info); > > if (ret < 0 && ret !=3D -ENOENT) > > goto out; > > - left_ret =3D ret; > > + left_ret =3D (info.nlink =3D=3D 0) ? -ENOENT : ret; > > + left_gen =3D info.gen; > > > > if (!sctx->parent_root) { > > right_ret =3D -ENOENT; > > } else { > > - ret =3D get_inode_gen(sctx->parent_root, ino, &right_ge= n); > > + ret =3D get_inode_info(sctx->parent_root, ino, &info); > > if (ret < 0 && ret !=3D -ENOENT) > > goto out; > > - right_ret =3D ret; > > + right_ret =3D (info.nlink =3D=3D 0) ? -ENOENT : ret; > > + right_gen =3D info.gen; > > } > > > > if (!left_ret && !right_ret) { > > @@ -6413,86 +6418,6 @@ static int finish_inode_if_needed(struct send_ct= x *sctx, int at_end) > > return ret; > > } > > > > -struct parent_paths_ctx { > > - struct list_head *refs; > > - struct send_ctx *sctx; > > -}; > > - > > -static int record_parent_ref(int num, u64 dir, int index, struct fs_pa= th *name, > > - void *ctx) > > -{ > > - struct parent_paths_ctx *ppctx =3D ctx; > > - > > - /* > > - * Pass 0 as the generation for the directory, we don't care ab= out it > > - * here as we have no new references to add, we just want to de= lete all > > - * references for an inode. > > - */ > > - return record_ref_in_tree(&ppctx->sctx->rbtree_deleted_refs, pp= ctx->refs, > > - name, dir, 0, ppctx->sctx); > > -} > > - > > -/* > > - * Issue unlink operations for all paths of the current inode found in= the > > - * parent snapshot. > > - */ > > -static int btrfs_unlink_all_paths(struct send_ctx *sctx) > > -{ > > - LIST_HEAD(deleted_refs); > > - struct btrfs_path *path; > > - struct btrfs_root *root =3D sctx->parent_root; > > - struct btrfs_key key; > > - struct btrfs_key found_key; > > - struct parent_paths_ctx ctx; > > - int iter_ret =3D 0; > > - int ret; > > - > > - path =3D alloc_path_for_send(); > > - if (!path) > > - return -ENOMEM; > > - > > - key.objectid =3D sctx->cur_ino; > > - key.type =3D BTRFS_INODE_REF_KEY; > > - key.offset =3D 0; > > - > > - ctx.refs =3D &deleted_refs; > > - ctx.sctx =3D sctx; > > - > > - btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) { > > - if (found_key.objectid !=3D key.objectid) > > - break; > > - if (found_key.type !=3D key.type && > > - found_key.type !=3D BTRFS_INODE_EXTREF_KEY) > > - break; > > - > > - ret =3D iterate_inode_ref(root, path, &found_key, 1, > > - record_parent_ref, &ctx); > > - if (ret < 0) > > - goto out; > > - } > > - /* Catch error found during iteration */ > > - if (iter_ret < 0) { > > - ret =3D iter_ret; > > - goto out; > > - } > > - > > - while (!list_empty(&deleted_refs)) { > > - struct recorded_ref *ref; > > - > > - ref =3D list_first_entry(&deleted_refs, struct recorded= _ref, list); > > - ret =3D send_unlink(sctx, ref->full_path); > > - if (ret < 0) > > - goto out; > > - recorded_ref_free(ref); > > - } > > - ret =3D 0; > > -out: > > - btrfs_free_path(path); > > - if (ret) > > - __free_recorded_refs(&deleted_refs); > > - return ret; > > -} > > - > > static void close_current_inode(struct send_ctx *sctx) > > { > > u64 i_size; > > @@ -6583,25 +6508,37 @@ static int changed_inode(struct send_ctx *sctx, > > * file descriptor against it or turning a RO snapshot into RW = mode, > > * keep an open file descriptor against a file, delete it and t= hen > > * turn the snapshot back to RO mode before using it for a send > > - * operation. So if we find such cases, ignore the inode and al= l its > > - * items completely if it's a new inode, or if it's a changed i= node > > - * make sure all its previous paths (from the parent snapshot) = are all > > - * unlinked and all other the inode items are ignored. > > + * operation. The former is what the receiver operation does. > > + * Therefore, if we want to send these snapshots soon after the= y're > > + * received, we need to handle orphan inodes as well. Moreover, > > + * orphans can appear not only in the send snapshot but also in= the > > + * parent snapshot. Here are several cases: > > + * > > + * Case 1: BTRFS_COMPARE_TREE_NEW > > + * | send snapshot | action > > + * -------------------------------- > > + * nlink | 0 | ignore > > + * > > + * Case 2: BTRFS_COMPARE_TREE_DELETED > > + * | parent snapshot | action > > + * ---------------------------------- > > + * nlink | 0 | as usual > > + * Note: No unlinks will be sent because there're no paths for = it. > > + * > > + * Case 3: BTRFS_COMPARE_TREE_CHANGED > > + * | | parent snapshot | send snapshot | action > > + * ------------------------------------------------------------= ----------- > > + * subcase 1 | nlink | 0 | 0 | ignore > > + * subcase 2 | nlink | >0 | 0 | new_ge= n(deletion) > > + * subcase 3 | nlink | 0 | >0 | new_ge= n(creation) > > + * > > */ > > - if (result =3D=3D BTRFS_COMPARE_TREE_NEW || > > - result =3D=3D BTRFS_COMPARE_TREE_CHANGED) { > > - u32 nlinks; > > - > > - nlinks =3D btrfs_inode_nlink(sctx->left_path->nodes[0],= left_ii); > > - if (nlinks =3D=3D 0) { > > + if (result =3D=3D BTRFS_COMPARE_TREE_NEW) { > > + if (btrfs_inode_nlink(sctx->left_path->nodes[0], left_i= i) =3D=3D > > + 0) { > > sctx->ignore_cur_inode =3D true; > > - if (result =3D=3D BTRFS_COMPARE_TREE_CHANGED) > > - ret =3D btrfs_unlink_all_paths(sctx); > > goto out; > > } > > - } > > - > > - if (result =3D=3D BTRFS_COMPARE_TREE_NEW) { > > sctx->cur_inode_gen =3D left_gen; > > sctx->cur_inode_new =3D true; > > sctx->cur_inode_deleted =3D false; > > @@ -6622,6 +6559,18 @@ static int changed_inode(struct send_ctx *sctx, > > sctx->cur_inode_mode =3D btrfs_inode_mode( > > sctx->right_path->nodes[0], right_ii); > > } else if (result =3D=3D BTRFS_COMPARE_TREE_CHANGED) { > > + u32 new_nlinks, old_nlinks; > > + > > + new_nlinks =3D btrfs_inode_nlink(sctx->left_path->nodes= [0], > > + left_ii); > > + old_nlinks =3D btrfs_inode_nlink(sctx->right_path->node= s[0], > > + right_ii); > > + if (new_nlinks =3D=3D 0 && old_nlinks =3D=3D 0) { > > + sctx->ignore_cur_inode =3D true; > > + goto out; > > + } else if (new_nlinks =3D=3D 0 || old_nlinks =3D=3D 0) = { > > + sctx->cur_inode_new_gen =3D 1; > > + } > > /* > > * We need to do some special handling in case the inod= e was > > * reported as changed with a changed generation number= . This > > @@ -6648,38 +6597,45 @@ static int changed_inode(struct send_ctx *sctx, > > /* > > * Now process the inode as if it was new. > > */ > > - sctx->cur_inode_gen =3D left_gen; > > - sctx->cur_inode_new =3D true; > > - sctx->cur_inode_deleted =3D false; > > - sctx->cur_inode_size =3D btrfs_inode_size( > > - sctx->left_path->nodes[0], left= _ii); > > - sctx->cur_inode_mode =3D btrfs_inode_mode( > > - sctx->left_path->nodes[0], left= _ii); > > - sctx->cur_inode_rdev =3D btrfs_inode_rdev( > > - sctx->left_path->nodes[0], left= _ii); > > - ret =3D send_create_inode_if_needed(sctx); > > - if (ret < 0) > > - goto out; > > + if (new_nlinks > 0) { > > + sctx->cur_inode_gen =3D left_gen; > > + sctx->cur_inode_new =3D true; > > + sctx->cur_inode_deleted =3D false; > > + sctx->cur_inode_size =3D btrfs_inode_si= ze( > > + sctx->left_path->nodes[= 0], > > + left_ii); > > + sctx->cur_inode_mode =3D btrfs_inode_mo= de( > > + sctx->left_path->nodes[= 0], > > + left_ii); > > + sctx->cur_inode_rdev =3D btrfs_inode_rd= ev( > > + sctx->left_path->nodes[= 0], > > + left_ii); > > + ret =3D send_create_inode_if_needed(sct= x); > > + if (ret < 0) > > + goto out; > > > > - ret =3D process_all_refs(sctx, BTRFS_COMPARE_TR= EE_NEW); > > - if (ret < 0) > > - goto out; > > - /* > > - * Advance send_progress now as we did not get = into > > - * process_recorded_refs_if_needed in the new_g= en case. > > - */ > > - sctx->send_progress =3D sctx->cur_ino + 1; > > + ret =3D process_all_refs(sctx, > > + BTRFS_COMPARE_TREE_NEW)= ; > > + if (ret < 0) > > + goto out; > > + /* > > + * Advance send_progress now as we did = not get > > + * into process_recorded_refs_if_needed= in the > > + * new_gen case. > > + */ > > + sctx->send_progress =3D sctx->cur_ino += 1; > > > > - /* > > - * Now process all extents and xattrs of the in= ode as if > > - * they were all new. > > - */ > > - ret =3D process_all_extents(sctx); > > - if (ret < 0) > > - goto out; > > - ret =3D process_all_new_xattrs(sctx); > > - if (ret < 0) > > - goto out; > > + /* > > + * Now process all extents and xattrs o= f the > > + * inode as if they were all new. > > + */ > > + ret =3D process_all_extents(sctx); > > + if (ret < 0) > > + goto out; > > + ret =3D process_all_new_xattrs(sctx); > > + if (ret < 0) > > + goto out; > > + } > > } else { > > sctx->cur_inode_gen =3D left_gen; > > sctx->cur_inode_new =3D false; > > -- > > 2.37.1 > >