[PATCH] Btrfs: incremental send, don't rename a directory too soon

[PATCH] Btrfs: incremental send, don't rename a directory too soon

[Filipe Manana]

There's one more case where we can't issue a rename operation for a
directory as soon as we process it. We used to delay directory renames
only if they have some ancestor directory with a higher inode number
that got renamed too, but there's another case where we need to delay
the rename too - when a directory A is renamed to the old name of a
directory B but that directory B has its rename delayed because it
has now (in the send root) an ancestor with a higher inode number that
was renamed. If we don't delay the directory rename in this case, the
receiving end of the send stream will attempt to rename A to the old
name of B before B got renamed to its new name, which results in a
"directory not empty" error. So fix this by delaying directory renames
for this case too.

Steps to reproduce:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ mkdir /mnt/a
  $ mkdir /mnt/b
  $ mkdir /mnt/c
  $ touch /mnt/a/file

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/c /mnt/x
  $ mv /mnt/a /mnt/x/y
  $ mv /mnt/b /mnt/a

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 -f /tmp/1.send
  $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.send

  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2
  $ btrfs receive /mnt2 -f /tmp/1.send
  $ btrfs receive /mnt2 -f /tmp/2.send
  ERROR: rename b -> a failed. Directory not empty

A test case for xfstests follows soon.

Reported-by: Ames Cornish <ames@cornishes.net>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/send.c | 164 ++++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 149 insertions(+), 15 deletions(-)

diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index fe58572..f28ab44 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -230,6 +230,7 @@ struct pending_dir_move {
 	u64 parent_ino;
 	u64 ino;
 	u64 gen;
+	bool is_orphan;
 	struct list_head update_refs;
 };
 
@@ -2984,7 +2985,8 @@ static int add_pending_dir_move(struct send_ctx *sctx,
 				u64 ino_gen,
 				u64 parent_ino,
 				struct list_head *new_refs,
-				struct list_head *deleted_refs)
+				struct list_head *deleted_refs,
+				const bool is_orphan)
 {
 	struct rb_node **p = &sctx->pending_dir_moves.rb_node;
 	struct rb_node *parent = NULL;
@@ -2999,6 +3001,7 @@ static int add_pending_dir_move(struct send_ctx *sctx,
 	pm->parent_ino = parent_ino;
 	pm->ino = ino;
 	pm->gen = ino_gen;
+	pm->is_orphan = is_orphan;
 	INIT_LIST_HEAD(&pm->list);
 	INIT_LIST_HEAD(&pm->update_refs);
 	RB_CLEAR_NODE(&pm->node);
@@ -3131,16 +3134,20 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
 	rmdir_ino = dm->rmdir_ino;
 	free_waiting_dir_move(sctx, dm);
 
-	ret = get_first_ref(sctx->parent_root, pm->ino,
-			    &parent_ino, &parent_gen, name);
-	if (ret < 0)
-		goto out;
-
-	ret = get_cur_path(sctx, parent_ino, parent_gen,
-			   from_path);
-	if (ret < 0)
-		goto out;
-	ret = fs_path_add_path(from_path, name);
+	if (pm->is_orphan) {
+		ret = gen_unique_name(sctx, pm->ino,
+				      pm->gen, from_path);
+	} else {
+		ret = get_first_ref(sctx->parent_root, pm->ino,
+				    &parent_ino, &parent_gen, name);
+		if (ret < 0)
+			goto out;
+		ret = get_cur_path(sctx, parent_ino, parent_gen,
+				   from_path);
+		if (ret < 0)
+			goto out;
+		ret = fs_path_add_path(from_path, name);
+	}
 	if (ret < 0)
 		goto out;
 
@@ -3150,7 +3157,8 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
 		LIST_HEAD(deleted_refs);
 		ASSERT(ancestor > BTRFS_FIRST_FREE_OBJECTID);
 		ret = add_pending_dir_move(sctx, pm->ino, pm->gen, ancestor,
-					   &pm->update_refs, &deleted_refs);
+					   &pm->update_refs, &deleted_refs,
+					   pm->is_orphan);
 		if (ret < 0)
 			goto out;
 		if (rmdir_ino) {
@@ -3283,6 +3291,120 @@ out:
 	return ret;
 }
 
+/*
+ * We might need to delay a directory rename even when no ancestor directory
+ * (in the send root) with a higher inode number than ours (sctx->cur_ino) was
+ * renamed. This happens when we rename a directory to the old name (the name
+ * in the parent root) of some other unrelated directory that got its rename
+ * delayed due to some ancestor with higher number that got renamed.
+ *
+ * Example:
+ *
+ * Parent snapshot:
+ * .                                       (ino 256)
+ * |---- a/                                (ino 257)
+ * |     |---- file                        (ino 260)
+ * |
+ * |---- b/                                (ino 258)
+ * |---- c/                                (ino 259)
+ *
+ * Send snapshot:
+ * .                                       (ino 256)
+ * |---- a/                                (ino 258)
+ * |---- x/                                (ino 259)
+ *       |---- y/                          (ino 257)
+ *             |----- file                 (ino 260)
+ *
+ * Here we can not rename 258 from 'b' to 'a' without the rename of inode 257
+ * from 'a' to 'x/y' happening first, which in turn depends on the rename of
+ * inode 259 from 'c' to 'x'. So the order of rename commands the send stream
+ * must issue is:
+ *
+ * 1 - rename 259 from 'c' to 'x'
+ * 2 - rename 257 from 'a' to 'x/y'
+ * 3 - rename 258 from 'b' to 'a'
+ *
+ * Returns 1 if the rename of sctx->cur_ino needs to be delayed, 0 if it can
+ * be done right away and < 0 on error.
+ */
+static int wait_for_dest_dir_move(struct send_ctx *sctx,
+				  struct recorded_ref *parent_ref,
+				  const bool is_orphan)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	struct btrfs_key di_key;
+	struct btrfs_dir_item *di;
+	u64 left_gen;
+	u64 right_gen;
+	int ret = 0;
+
+	path = alloc_path_for_send();
+	if (!path)
+		return -ENOMEM;
+
+	key.objectid = parent_ref->dir;
+	key.type = BTRFS_DIR_ITEM_KEY;
+	key.offset = btrfs_name_hash(parent_ref->name, parent_ref->name_len);
+
+	ret = btrfs_search_slot(NULL, sctx->parent_root, &key, path, 0, 0);
+	if (ret < 0) {
+		goto out;
+	} else if (ret > 0) {
+		ret = 0;
+		goto out;
+	}
+
+	di = btrfs_match_dir_item_name(sctx->parent_root, path,
+				       parent_ref->name, parent_ref->name_len);
+	if (!di) {
+		ret = 0;
+		goto out;
+	}
+	/*
+	 * di_key.objectid has the number of the inode that has a dentry in the
+	 * parent directory with the same name that sctx->cur_ino is being
+	 * renamed to. We need to check if that inode is in the send root as
+	 * well and if it is currently marked as an inode with a pending rename,
+	 * if it is, we need to delay the rename of sctx->cur_ino as well, so
+	 * that it happens after that other inode is renamed.
+	 */
+	btrfs_dir_item_key_to_cpu(path->nodes[0], di, &di_key);
+
+	ret = get_inode_info(sctx->parent_root, di_key.objectid, NULL,
+			     &left_gen, NULL, NULL, NULL, NULL);
+	if (ret < 0)
+		goto out;
+	ret = get_inode_info(sctx->send_root, di_key.objectid, NULL,
+			     &right_gen, NULL, NULL, NULL, NULL);
+	if (ret < 0) {
+		if (ret == -ENOENT)
+			ret = 0;
+		goto out;
+	}
+
+	/* Different inode, no need to delay the rename of sctx->cur_ino */
+	if (right_gen != left_gen) {
+		ret = 0;
+		goto out;
+	}
+
+	if (is_waiting_for_move(sctx, di_key.objectid)) {
+		ret = add_pending_dir_move(sctx,
+					   sctx->cur_ino,
+					   sctx->cur_inode_gen,
+					   di_key.objectid,
+					   &sctx->new_refs,
+					   &sctx->deleted_refs,
+					   is_orphan);
+		if (!ret)
+			ret = 1;
+	}
+out:
+	btrfs_free_path(path);
+	return ret;
+}
+
 static int wait_for_parent_move(struct send_ctx *sctx,
 				struct recorded_ref *parent_ref)
 {
@@ -3349,7 +3471,8 @@ out:
 					   sctx->cur_inode_gen,
 					   ino,
 					   &sctx->new_refs,
-					   &sctx->deleted_refs);
+					   &sctx->deleted_refs,
+					   false);
 		if (!ret)
 			ret = 1;
 	}
@@ -3372,6 +3495,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 	int did_overwrite = 0;
 	int is_orphan = 0;
 	u64 last_dir_ino_rm = 0;
+	bool can_rename = true;
 
 verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
 
@@ -3490,12 +3614,22 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
 			}
 		}
 
+		if (S_ISDIR(sctx->cur_inode_mode) && sctx->parent_root) {
+			ret = wait_for_dest_dir_move(sctx, cur, is_orphan);
+			if (ret < 0)
+				goto out;
+			if (ret == 1) {
+				can_rename = false;
+				*pending_move = 1;
+			}
+		}
+
 		/*
 		 * link/move the ref to the new place. If we have an orphan
 		 * inode, move it and update valid_path. If not, link or move
 		 * it depending on the inode mode.
 		 */
-		if (is_orphan) {
+		if (is_orphan && can_rename) {
 			ret = send_rename(sctx, valid_path, cur->full_path);
 			if (ret < 0)
 				goto out;
@@ -3503,7 +3637,7 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
 			ret = fs_path_copy(valid_path, cur->full_path);
 			if (ret < 0)
 				goto out;
-		} else {
+		} else if (can_rename) {
 			if (S_ISDIR(sctx->cur_inode_mode)) {
 				/*
 				 * Dirs can't be linked, so move it. For moved
-- 
2.1.3

[PATCH v2] Btrfs: incremental send, don't rename a directory too soon

[Filipe Manana]

There's one more case where we can't issue a rename operation for a
directory as soon as we process it. We used to delay directory renames
only if they have some ancestor directory with a higher inode number
that got renamed too, but there's another case where we need to delay
the rename too - when a directory A is renamed to the old name of a
directory B but that directory B has its rename delayed because it
has now (in the send root) an ancestor with a higher inode number that
was renamed. If we don't delay the directory rename in this case, the
receiving end of the send stream will attempt to rename A to the old
name of B before B got renamed to its new name, which results in a
"directory not empty" error. So fix this by delaying directory renames
for this case too.

Steps to reproduce:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ mkdir /mnt/a
  $ mkdir /mnt/b
  $ mkdir /mnt/c
  $ touch /mnt/a/file

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/c /mnt/x
  $ mv /mnt/a /mnt/x/y
  $ mv /mnt/b /mnt/a

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 -f /tmp/1.send
  $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.send

  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2
  $ btrfs receive /mnt2 -f /tmp/1.send
  $ btrfs receive /mnt2 -f /tmp/2.send
  ERROR: rename b -> a failed. Directory not empty

A test case for xfstests follows soon.

Reported-by: Ames Cornish <ames@cornishes.net>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
---

V2: Skip btree searches if rbtree of waiting dir moves is empty.

 fs/btrfs/send.c | 171 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 156 insertions(+), 15 deletions(-)

diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index fe58572..d6033f5 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -230,6 +230,7 @@ struct pending_dir_move {
 	u64 parent_ino;
 	u64 ino;
 	u64 gen;
+	bool is_orphan;
 	struct list_head update_refs;
 };
 
@@ -2984,7 +2985,8 @@ static int add_pending_dir_move(struct send_ctx *sctx,
 				u64 ino_gen,
 				u64 parent_ino,
 				struct list_head *new_refs,
-				struct list_head *deleted_refs)
+				struct list_head *deleted_refs,
+				const bool is_orphan)
 {
 	struct rb_node **p = &sctx->pending_dir_moves.rb_node;
 	struct rb_node *parent = NULL;
@@ -2999,6 +3001,7 @@ static int add_pending_dir_move(struct send_ctx *sctx,
 	pm->parent_ino = parent_ino;
 	pm->ino = ino;
 	pm->gen = ino_gen;
+	pm->is_orphan = is_orphan;
 	INIT_LIST_HEAD(&pm->list);
 	INIT_LIST_HEAD(&pm->update_refs);
 	RB_CLEAR_NODE(&pm->node);
@@ -3131,16 +3134,20 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
 	rmdir_ino = dm->rmdir_ino;
 	free_waiting_dir_move(sctx, dm);
 
-	ret = get_first_ref(sctx->parent_root, pm->ino,
-			    &parent_ino, &parent_gen, name);
-	if (ret < 0)
-		goto out;
-
-	ret = get_cur_path(sctx, parent_ino, parent_gen,
-			   from_path);
-	if (ret < 0)
-		goto out;
-	ret = fs_path_add_path(from_path, name);
+	if (pm->is_orphan) {
+		ret = gen_unique_name(sctx, pm->ino,
+				      pm->gen, from_path);
+	} else {
+		ret = get_first_ref(sctx->parent_root, pm->ino,
+				    &parent_ino, &parent_gen, name);
+		if (ret < 0)
+			goto out;
+		ret = get_cur_path(sctx, parent_ino, parent_gen,
+				   from_path);
+		if (ret < 0)
+			goto out;
+		ret = fs_path_add_path(from_path, name);
+	}
 	if (ret < 0)
 		goto out;
 
@@ -3150,7 +3157,8 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
 		LIST_HEAD(deleted_refs);
 		ASSERT(ancestor > BTRFS_FIRST_FREE_OBJECTID);
 		ret = add_pending_dir_move(sctx, pm->ino, pm->gen, ancestor,
-					   &pm->update_refs, &deleted_refs);
+					   &pm->update_refs, &deleted_refs,
+					   pm->is_orphan);
 		if (ret < 0)
 			goto out;
 		if (rmdir_ino) {
@@ -3283,6 +3291,127 @@ out:
 	return ret;
 }
 
+/*
+ * We might need to delay a directory rename even when no ancestor directory
+ * (in the send root) with a higher inode number than ours (sctx->cur_ino) was
+ * renamed. This happens when we rename a directory to the old name (the name
+ * in the parent root) of some other unrelated directory that got its rename
+ * delayed due to some ancestor with higher number that got renamed.
+ *
+ * Example:
+ *
+ * Parent snapshot:
+ * .                                       (ino 256)
+ * |---- a/                                (ino 257)
+ * |     |---- file                        (ino 260)
+ * |
+ * |---- b/                                (ino 258)
+ * |---- c/                                (ino 259)
+ *
+ * Send snapshot:
+ * .                                       (ino 256)
+ * |---- a/                                (ino 258)
+ * |---- x/                                (ino 259)
+ *       |---- y/                          (ino 257)
+ *             |----- file                 (ino 260)
+ *
+ * Here we can not rename 258 from 'b' to 'a' without the rename of inode 257
+ * from 'a' to 'x/y' happening first, which in turn depends on the rename of
+ * inode 259 from 'c' to 'x'. So the order of rename commands the send stream
+ * must issue is:
+ *
+ * 1 - rename 259 from 'c' to 'x'
+ * 2 - rename 257 from 'a' to 'x/y'
+ * 3 - rename 258 from 'b' to 'a'
+ *
+ * Returns 1 if the rename of sctx->cur_ino needs to be delayed, 0 if it can
+ * be done right away and < 0 on error.
+ */
+static int wait_for_dest_dir_move(struct send_ctx *sctx,
+				  struct recorded_ref *parent_ref,
+				  const bool is_orphan)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	struct btrfs_key di_key;
+	struct btrfs_dir_item *di;
+	u64 left_gen;
+	u64 right_gen;
+	int ret = 0;
+
+	if (RB_EMPTY_ROOT(&sctx->waiting_dir_moves))
+		return 0;
+
+	path = alloc_path_for_send();
+	if (!path)
+		return -ENOMEM;
+
+	key.objectid = parent_ref->dir;
+	key.type = BTRFS_DIR_ITEM_KEY;
+	key.offset = btrfs_name_hash(parent_ref->name, parent_ref->name_len);
+
+	ret = btrfs_search_slot(NULL, sctx->parent_root, &key, path, 0, 0);
+	if (ret < 0) {
+		goto out;
+	} else if (ret > 0) {
+		ret = 0;
+		goto out;
+	}
+
+	di = btrfs_match_dir_item_name(sctx->parent_root, path,
+				       parent_ref->name, parent_ref->name_len);
+	if (!di) {
+		ret = 0;
+		goto out;
+	}
+	/*
+	 * di_key.objectid has the number of the inode that has a dentry in the
+	 * parent directory with the same name that sctx->cur_ino is being
+	 * renamed to. We need to check if that inode is in the send root as
+	 * well and if it is currently marked as an inode with a pending rename,
+	 * if it is, we need to delay the rename of sctx->cur_ino as well, so
+	 * that it happens after that other inode is renamed.
+	 */
+	btrfs_dir_item_key_to_cpu(path->nodes[0], di, &di_key);
+	if (di_key.type != BTRFS_INODE_ITEM_KEY) {
+		ret = 0;
+		goto out;
+	}
+
+	ret = get_inode_info(sctx->parent_root, di_key.objectid, NULL,
+			     &left_gen, NULL, NULL, NULL, NULL);
+	if (ret < 0)
+		goto out;
+	ret = get_inode_info(sctx->send_root, di_key.objectid, NULL,
+			     &right_gen, NULL, NULL, NULL, NULL);
+	if (ret < 0) {
+		if (ret == -ENOENT)
+			ret = 0;
+		goto out;
+	}
+
+	/* Different inode, no need to delay the rename of sctx->cur_ino */
+	if (right_gen != left_gen) {
+		ret = 0;
+		goto out;
+	}
+
+	if (is_waiting_for_move(sctx, di_key.objectid)) {
+		ret = add_pending_dir_move(sctx,
+					   sctx->cur_ino,
+					   sctx->cur_inode_gen,
+					   di_key.objectid,
+					   &sctx->new_refs,
+					   &sctx->deleted_refs,
+					   is_orphan);
+		if (!ret)
+			ret = 1;
+	}
+out:
+	btrfs_free_path(path);
+	return ret;
+}
+
 static int wait_for_parent_move(struct send_ctx *sctx,
 				struct recorded_ref *parent_ref)
 {
@@ -3349,7 +3478,8 @@ out:
 					   sctx->cur_inode_gen,
 					   ino,
 					   &sctx->new_refs,
-					   &sctx->deleted_refs);
+					   &sctx->deleted_refs,
+					   false);
 		if (!ret)
 			ret = 1;
 	}
@@ -3372,6 +3502,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 	int did_overwrite = 0;
 	int is_orphan = 0;
 	u64 last_dir_ino_rm = 0;
+	bool can_rename = true;
 
 verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
 
@@ -3490,12 +3621,22 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
 			}
 		}
 
+		if (S_ISDIR(sctx->cur_inode_mode) && sctx->parent_root) {
+			ret = wait_for_dest_dir_move(sctx, cur, is_orphan);
+			if (ret < 0)
+				goto out;
+			if (ret == 1) {
+				can_rename = false;
+				*pending_move = 1;
+			}
+		}
+
 		/*
 		 * link/move the ref to the new place. If we have an orphan
 		 * inode, move it and update valid_path. If not, link or move
 		 * it depending on the inode mode.
 		 */
-		if (is_orphan) {
+		if (is_orphan && can_rename) {
 			ret = send_rename(sctx, valid_path, cur->full_path);
 			if (ret < 0)
 				goto out;
@@ -3503,7 +3644,7 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
 			ret = fs_path_copy(valid_path, cur->full_path);
 			if (ret < 0)
 				goto out;
-		} else {
+		} else if (can_rename) {
 			if (S_ISDIR(sctx->cur_inode_mode)) {
 				/*
 				 * Dirs can't be linked, so move it. For moved
-- 
2.1.3

Re: [PATCH v2] Btrfs: incremental send, don't rename a directory too soon

[Robbie Ko]

Hi,

After applying the patch, I got WARN_ON.
btrfs progs finished without any error message,
but received subvolume is not the same as send subvolume.

Here's the related information.
thanks,
robbieko

uanme -a
Linux ubuntu 4.0.0-rc4-custom #2 SMP Tue Apr 14 11:43:00 CST 2015
x86_64 x86_64 x86_64 GNU/Linux
btrfs --version
Btrfs v3.14.1

Steps to reproduce:

 $ mkfs.btrfs -f /dev/sdb
 $ mount /dev/sdb /mnt
 $ mkfs.btrfs -f /dev/sdc
 $ mount /dev/sdc /mnt2

$ mkdir -p /mnt/data
$ mkdir -p /mnt/data/n1/n2
$ mkdir -p /mnt/data/n4
$ mkdir -p /mnt/data/n1/n2/p1
$ mkdir -p /mnt/data/t4
$ mkdir -p /mnt/data/p1
$ mkdir -p /mnt/data/p1/2

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

$ mv /mnt/data/n1/n2 /mnt/data/t4
$ mv /mnt/data/n4 /mnt/data/t4/n2
$ mv /mnt/data/t4/n2/p1 /mnt/data/t4/p1
$ mv /mnt/data/p1 /mnt/data/t4/n2

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2

Call trace message

[  135.498533] ------------[ cut here ]------------

[  135.498557] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5934
btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]()

[  135.498560] Modules linked in: nf_conntrack_ipv4(E)
nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)

[  135.498578] CPU: 1 PID: 2346 Comm: btrfs Tainted: G         E
4.0.0-rc4-custom #3

[  135.498580] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
VirtualBox 12/01/2006

[  135.498583]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
0000000000000007

[  135.498586]  0000000000000000 ffff88007a233c48 ffffffff8107452a
ffffc90000567000

[  135.498590]  ffff8800799f1400 ffff8800799f1418 ffff88007b3f82d0
ffff880079f60000

[  135.498593] Call Trace:

[  135.498602]  [<ffffffff817b62f3>] dump_stack+0x45/0x57

[  135.498609]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0

[  135.498614]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20

[  135.498626]  [<ffffffffc04f5c6c>] btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]

[  135.498632]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0

[  135.498638]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90

[  135.498643]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530

[  135.498655]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]

[  135.498660]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80

[  135.498665]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20

[  135.498679]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90

[  135.498686]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730

[  135.498698]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70

[  135.498703]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0

[  135.498710]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0

[  135.498715]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0

[  135.498722]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0

[  135.498728]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370

[  135.498733]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0

[  135.498738]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20

[  135.498839]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90

[  135.498845]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b

[  135.498848] ---[ end trace e1dd916182de3a9d ]---

[  135.498851] ------------[ cut here ]------------

[  135.498871] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5951
btrfs_ioctl_send+0x28f/0x11e0 [btrfs]()

[  135.498894] Modules linked in: nf_conntrack_ipv4(E)
nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)

[  135.498900] CPU: 1 PID: 2346 Comm: btrfs Tainted: G     W   E
4.0.0-rc4-custom #3

[  135.498903] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
VirtualBox 12/01/2006

[  135.498910]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
000000004c724c72

[  135.498918]  0000000000000000 ffff88007a233c48 ffffffff8107452a
ffff88007a233c38

[  135.498923]  ffff8800799f1400 ffff880078d52cc0 ffff880078d52cd8
ffff8800799f15d8

[  135.498927] Call Trace:

[  135.498937]  [<ffffffff817b62f3>] dump_stack+0x45/0x57

[  135.498945]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0

[  135.498951]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20

[  135.498975]  [<ffffffffc04f52af>] btrfs_ioctl_send+0x28f/0x11e0 [btrfs]

[  135.498984]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0

[  135.498990]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90

[  135.498996]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530

[  135.499023]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]

[  135.499031]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80

[  135.499037]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20

[  135.499046]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90

[  135.499055]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730

[  135.499061]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70

[  135.499069]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0

[  135.499078]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0

[  135.499087]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0

[  135.499096]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0

[  135.499106]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370

[  135.499115]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0

[  135.499121]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20

[  135.499131]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90

[  135.499140]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b

[  135.499144] ---[ end trace e1dd916182de3a9e ]---

Re: [PATCH v2] Btrfs: incremental send, don't rename a directory too soon

[Filipe David Manana]

On Tue, Apr 14, 2015 at 8:33 AM, Robbie Ko <robbieko@synology.com> wrote:
> Hi,
>
> After applying the patch, I got WARN_ON.
> btrfs progs finished without any error message,
> but received subvolume is not the same as send subvolume.
>
> Here's the related information.
> thanks,
> robbieko
>
> uanme -a
> Linux ubuntu 4.0.0-rc4-custom #2 SMP Tue Apr 14 11:43:00 CST 2015
> x86_64 x86_64 x86_64 GNU/Linux
> btrfs --version
> Btrfs v3.14.1
>
> Steps to reproduce:
>
>  $ mkfs.btrfs -f /dev/sdb
>  $ mount /dev/sdb /mnt
>  $ mkfs.btrfs -f /dev/sdc
>  $ mount /dev/sdc /mnt2
>
> $ mkdir -p /mnt/data
> $ mkdir -p /mnt/data/n1/n2
> $ mkdir -p /mnt/data/n4
> $ mkdir -p /mnt/data/n1/n2/p1
> $ mkdir -p /mnt/data/t4
> $ mkdir -p /mnt/data/p1
> $ mkdir -p /mnt/data/p1/2
>
>   $ btrfs subvolume snapshot -r /mnt /mnt/snap1
>
> $ mv /mnt/data/n1/n2 /mnt/data/t4
> $ mv /mnt/data/n4 /mnt/data/t4/n2
> $ mv /mnt/data/t4/n2/p1 /mnt/data/t4/p1
> $ mv /mnt/data/p1 /mnt/data/t4/n2
>
>   $ btrfs subvolume snapshot -r /mnt /mnt/snap2
>
>   $ btrfs send /mnt/snap1 | btrfs receive /mnt2
>   $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2

So this is a new case, different from the ones you've sent before, isn't it?

You should have all previous patches applied too, not just this one
you're replying to.
Also, it isn't clear, are you saying this happens only with this
particular patch applied but doesn't happen without it (and all other
recent ones)?

thanks


>
> Call trace message
>
> [  135.498533] ------------[ cut here ]------------
>
> [  135.498557] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5934
> btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]()
>
> [  135.498560] Modules linked in: nf_conntrack_ipv4(E)
> nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
> nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
> x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
> ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
> ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
> mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
> usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)
>
> [  135.498578] CPU: 1 PID: 2346 Comm: btrfs Tainted: G         E
> 4.0.0-rc4-custom #3
>
> [  135.498580] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
> VirtualBox 12/01/2006
>
> [  135.498583]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
> 0000000000000007
>
> [  135.498586]  0000000000000000 ffff88007a233c48 ffffffff8107452a
> ffffc90000567000
>
> [  135.498590]  ffff8800799f1400 ffff8800799f1418 ffff88007b3f82d0
> ffff880079f60000
>
> [  135.498593] Call Trace:
>
> [  135.498602]  [<ffffffff817b62f3>] dump_stack+0x45/0x57
>
> [  135.498609]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0
>
> [  135.498614]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20
>
> [  135.498626]  [<ffffffffc04f5c6c>] btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]
>
> [  135.498632]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0
>
> [  135.498638]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90
>
> [  135.498643]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530
>
> [  135.498655]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]
>
> [  135.498660]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80
>
> [  135.498665]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20
>
> [  135.498679]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90
>
> [  135.498686]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730
>
> [  135.498698]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70
>
> [  135.498703]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0
>
> [  135.498710]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0
>
> [  135.498715]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0
>
> [  135.498722]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0
>
> [  135.498728]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370
>
> [  135.498733]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0
>
> [  135.498738]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20
>
> [  135.498839]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90
>
> [  135.498845]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b
>
> [  135.498848] ---[ end trace e1dd916182de3a9d ]---
>
> [  135.498851] ------------[ cut here ]------------
>
> [  135.498871] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5951
> btrfs_ioctl_send+0x28f/0x11e0 [btrfs]()
>
> [  135.498894] Modules linked in: nf_conntrack_ipv4(E)
> nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
> nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
> x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
> ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
> ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
> mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
> usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)
>
> [  135.498900] CPU: 1 PID: 2346 Comm: btrfs Tainted: G     W   E
> 4.0.0-rc4-custom #3
>
> [  135.498903] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
> VirtualBox 12/01/2006
>
> [  135.498910]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
> 000000004c724c72
>
> [  135.498918]  0000000000000000 ffff88007a233c48 ffffffff8107452a
> ffff88007a233c38
>
> [  135.498923]  ffff8800799f1400 ffff880078d52cc0 ffff880078d52cd8
> ffff8800799f15d8
>
> [  135.498927] Call Trace:
>
> [  135.498937]  [<ffffffff817b62f3>] dump_stack+0x45/0x57
>
> [  135.498945]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0
>
> [  135.498951]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20
>
> [  135.498975]  [<ffffffffc04f52af>] btrfs_ioctl_send+0x28f/0x11e0 [btrfs]
>
> [  135.498984]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0
>
> [  135.498990]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90
>
> [  135.498996]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530
>
> [  135.499023]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]
>
> [  135.499031]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80
>
> [  135.499037]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20
>
> [  135.499046]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90
>
> [  135.499055]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730
>
> [  135.499061]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70
>
> [  135.499069]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0
>
> [  135.499078]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0
>
> [  135.499087]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0
>
> [  135.499096]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0
>
> [  135.499106]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370
>
> [  135.499115]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0
>
> [  135.499121]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20
>
> [  135.499131]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90
>
> [  135.499140]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b
>
> [  135.499144] ---[ end trace e1dd916182de3a9e ]---



-- 
Filipe David Manana,

"Reasonable men adapt themselves to the world.
 Unreasonable men adapt the world to themselves.
 That's why all progress depends on unreasonable men."

Re: [PATCH v2] Btrfs: incremental send, don't rename a directory too soon

[Robbie Ko]

Hi,

Sorry for not making it clear.

2015-04-14 16:16 GMT+08:00 Filipe David Manana <fdmanana@gmail.com>:
> On Tue, Apr 14, 2015 at 8:33 AM, Robbie Ko <robbieko@synology.com> wrote:
>> Hi,
>>
>> After applying the patch, I got WARN_ON.
>> btrfs progs finished without any error message,
>> but received subvolume is not the same as send subvolume.
>>
>> Here's the related information.
>> thanks,
>> robbieko
>>
>> uanme -a
>> Linux ubuntu 4.0.0-rc4-custom #2 SMP Tue Apr 14 11:43:00 CST 2015
>> x86_64 x86_64 x86_64 GNU/Linux
>> btrfs --version
>> Btrfs v3.14.1
>>
>> Steps to reproduce:
>>
>>  $ mkfs.btrfs -f /dev/sdb
>>  $ mount /dev/sdb /mnt
>>  $ mkfs.btrfs -f /dev/sdc
>>  $ mount /dev/sdc /mnt2
>>
>> $ mkdir -p /mnt/data
>> $ mkdir -p /mnt/data/n1/n2
>> $ mkdir -p /mnt/data/n4
>> $ mkdir -p /mnt/data/n1/n2/p1
>> $ mkdir -p /mnt/data/t4
>> $ mkdir -p /mnt/data/p1
>> $ mkdir -p /mnt/data/p1/2
>>
>>   $ btrfs subvolume snapshot -r /mnt /mnt/snap1
>>
>> $ mv /mnt/data/n1/n2 /mnt/data/t4
>> $ mv /mnt/data/n4 /mnt/data/t4/n2
>> $ mv /mnt/data/t4/n2/p1 /mnt/data/t4/p1
>> $ mv /mnt/data/p1 /mnt/data/t4/n2
>>
>>   $ btrfs subvolume snapshot -r /mnt /mnt/snap2
>>
>>   $ btrfs send /mnt/snap1 | btrfs receive /mnt2
>>   $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
>
> So this is a new case, different from the ones you've sent before, isn't it?
>
> You should have all previous patches applied too, not just this one
> you're replying to.

Hi,

I have applied all the patches fixed recently.
Then WARN_ON happened with steps mentioned above.
I tested it without these patches, no WARN_ON but the following error
appeared instead.
ERROR: rename data/t4/n2/p1 -> data/t4/n2/p1/p1 failed. Invalid argument

I started to revert these patches and found that this patch causes the
WARN_ON problem.

I'm not sure whether it's a new case.

thanks,
robbieko

> Also, it isn't clear, are you saying this happens only with this
> particular patch applied but doesn't happen without it (and all other
> recent ones)?
>
> thanks
>
>
>>
>> Call trace message
>>
>> [  135.498533] ------------[ cut here ]------------
>>
>> [  135.498557] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5934
>> btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]()
>>
>> [  135.498560] Modules linked in: nf_conntrack_ipv4(E)
>> nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
>> nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
>> x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
>> ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
>> ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
>> mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
>> usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)
>>
>> [  135.498578] CPU: 1 PID: 2346 Comm: btrfs Tainted: G         E
>> 4.0.0-rc4-custom #3
>>
>> [  135.498580] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
>> VirtualBox 12/01/2006
>>
>> [  135.498583]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
>> 0000000000000007
>>
>> [  135.498586]  0000000000000000 ffff88007a233c48 ffffffff8107452a
>> ffffc90000567000
>>
>> [  135.498590]  ffff8800799f1400 ffff8800799f1418 ffff88007b3f82d0
>> ffff880079f60000
>>
>> [  135.498593] Call Trace:
>>
>> [  135.498602]  [<ffffffff817b62f3>] dump_stack+0x45/0x57
>>
>> [  135.498609]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0
>>
>> [  135.498614]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20
>>
>> [  135.498626]  [<ffffffffc04f5c6c>] btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]
>>
>> [  135.498632]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0
>>
>> [  135.498638]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90
>>
>> [  135.498643]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530
>>
>> [  135.498655]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]
>>
>> [  135.498660]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80
>>
>> [  135.498665]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20
>>
>> [  135.498679]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90
>>
>> [  135.498686]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730
>>
>> [  135.498698]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70
>>
>> [  135.498703]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0
>>
>> [  135.498710]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0
>>
>> [  135.498715]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0
>>
>> [  135.498722]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0
>>
>> [  135.498728]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370
>>
>> [  135.498733]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0
>>
>> [  135.498738]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20
>>
>> [  135.498839]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90
>>
>> [  135.498845]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b
>>
>> [  135.498848] ---[ end trace e1dd916182de3a9d ]---
>>
>> [  135.498851] ------------[ cut here ]------------
>>
>> [  135.498871] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5951
>> btrfs_ioctl_send+0x28f/0x11e0 [btrfs]()
>>
>> [  135.498894] Modules linked in: nf_conntrack_ipv4(E)
>> nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
>> nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
>> x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
>> ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
>> ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
>> mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
>> usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)
>>
>> [  135.498900] CPU: 1 PID: 2346 Comm: btrfs Tainted: G     W   E
>> 4.0.0-rc4-custom #3
>>
>> [  135.498903] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
>> VirtualBox 12/01/2006
>>
>> [  135.498910]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
>> 000000004c724c72
>>
>> [  135.498918]  0000000000000000 ffff88007a233c48 ffffffff8107452a
>> ffff88007a233c38
>>
>> [  135.498923]  ffff8800799f1400 ffff880078d52cc0 ffff880078d52cd8
>> ffff8800799f15d8
>>
>> [  135.498927] Call Trace:
>>
>> [  135.498937]  [<ffffffff817b62f3>] dump_stack+0x45/0x57
>>
>> [  135.498945]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0
>>
>> [  135.498951]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20
>>
>> [  135.498975]  [<ffffffffc04f52af>] btrfs_ioctl_send+0x28f/0x11e0 [btrfs]
>>
>> [  135.498984]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0
>>
>> [  135.498990]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90
>>
>> [  135.498996]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530
>>
>> [  135.499023]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]
>>
>> [  135.499031]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80
>>
>> [  135.499037]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20
>>
>> [  135.499046]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90
>>
>> [  135.499055]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730
>>
>> [  135.499061]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70
>>
>> [  135.499069]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0
>>
>> [  135.499078]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0
>>
>> [  135.499087]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0
>>
>> [  135.499096]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0
>>
>> [  135.499106]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370
>>
>> [  135.499115]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0
>>
>> [  135.499121]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20
>>
>> [  135.499131]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90
>>
>> [  135.499140]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b
>>
>> [  135.499144] ---[ end trace e1dd916182de3a9e ]---
>
>
>
> --
> Filipe David Manana,
>
> "Reasonable men adapt themselves to the world.
>  Unreasonable men adapt the world to themselves.
>  That's why all progress depends on unreasonable men."

Re: [PATCH v2] Btrfs: incremental send, don't rename a directory too soon

[Filipe David Manana]

On Tue, Apr 14, 2015 at 12:09 PM, Robbie Ko <robbieko@synology.com> wrote:
> Hi,
>
> Sorry for not making it clear.
>
> 2015-04-14 16:16 GMT+08:00 Filipe David Manana <fdmanana@gmail.com>:
>> On Tue, Apr 14, 2015 at 8:33 AM, Robbie Ko <robbieko@synology.com> wrote:
>>> Hi,
>>>
>>> After applying the patch, I got WARN_ON.
>>> btrfs progs finished without any error message,
>>> but received subvolume is not the same as send subvolume.
>>>
>>> Here's the related information.
>>> thanks,
>>> robbieko
>>>
>>> uanme -a
>>> Linux ubuntu 4.0.0-rc4-custom #2 SMP Tue Apr 14 11:43:00 CST 2015
>>> x86_64 x86_64 x86_64 GNU/Linux
>>> btrfs --version
>>> Btrfs v3.14.1
>>>
>>> Steps to reproduce:
>>>
>>>  $ mkfs.btrfs -f /dev/sdb
>>>  $ mount /dev/sdb /mnt
>>>  $ mkfs.btrfs -f /dev/sdc
>>>  $ mount /dev/sdc /mnt2
>>>
>>> $ mkdir -p /mnt/data
>>> $ mkdir -p /mnt/data/n1/n2
>>> $ mkdir -p /mnt/data/n4
>>> $ mkdir -p /mnt/data/n1/n2/p1
>>> $ mkdir -p /mnt/data/t4
>>> $ mkdir -p /mnt/data/p1
>>> $ mkdir -p /mnt/data/p1/2
>>>
>>>   $ btrfs subvolume snapshot -r /mnt /mnt/snap1
>>>
>>> $ mv /mnt/data/n1/n2 /mnt/data/t4
>>> $ mv /mnt/data/n4 /mnt/data/t4/n2
>>> $ mv /mnt/data/t4/n2/p1 /mnt/data/t4/p1
>>> $ mv /mnt/data/p1 /mnt/data/t4/n2
>>>
>>>   $ btrfs subvolume snapshot -r /mnt /mnt/snap2
>>>
>>>   $ btrfs send /mnt/snap1 | btrfs receive /mnt2
>>>   $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
>>
>> So this is a new case, different from the ones you've sent before, isn't it?
>>
>> You should have all previous patches applied too, not just this one
>> you're replying to.
>
> Hi,
>
> I have applied all the patches fixed recently.
> Then WARN_ON happened with steps mentioned above.
> I tested it without these patches, no WARN_ON but the following error
> appeared instead.
> ERROR: rename data/t4/n2/p1 -> data/t4/n2/p1/p1 failed. Invalid argument
>
> I started to revert these patches and found that this patch causes the
> WARN_ON problem.
>
> I'm not sure whether it's a new case.

So it's a case that didn't work neither before nor after all the
recent fixes, but for different reasons.
I have 2 cases here, one triggered by your fuzz tester script and
another one I know of for quite some time (involving creation of new
directories and removing old ones in the second snapshot) but haven't
had the time to find a solution without breaking other cases that are
currently working (and have xfstests). Haven't checked however if your
reproducer fails for the same reasons as those 2 cases I know of.

thanks

>
> thanks,
> robbieko
>
>> Also, it isn't clear, are you saying this happens only with this
>> particular patch applied but doesn't happen without it (and all other
>> recent ones)?
>>
>> thanks
>>
>>
>>>
>>> Call trace message
>>>
>>> [  135.498533] ------------[ cut here ]------------
>>>
>>> [  135.498557] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5934
>>> btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]()
>>>
>>> [  135.498560] Modules linked in: nf_conntrack_ipv4(E)
>>> nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
>>> nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
>>> x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
>>> ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
>>> ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
>>> mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
>>> usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)
>>>
>>> [  135.498578] CPU: 1 PID: 2346 Comm: btrfs Tainted: G         E
>>> 4.0.0-rc4-custom #3
>>>
>>> [  135.498580] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
>>> VirtualBox 12/01/2006
>>>
>>> [  135.498583]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
>>> 0000000000000007
>>>
>>> [  135.498586]  0000000000000000 ffff88007a233c48 ffffffff8107452a
>>> ffffc90000567000
>>>
>>> [  135.498590]  ffff8800799f1400 ffff8800799f1418 ffff88007b3f82d0
>>> ffff880079f60000
>>>
>>> [  135.498593] Call Trace:
>>>
>>> [  135.498602]  [<ffffffff817b62f3>] dump_stack+0x45/0x57
>>>
>>> [  135.498609]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0
>>>
>>> [  135.498614]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20
>>>
>>> [  135.498626]  [<ffffffffc04f5c6c>] btrfs_ioctl_send+0xc4c/0x11e0 [btrfs]
>>>
>>> [  135.498632]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0
>>>
>>> [  135.498638]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90
>>>
>>> [  135.498643]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530
>>>
>>> [  135.498655]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]
>>>
>>> [  135.498660]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80
>>>
>>> [  135.498665]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20
>>>
>>> [  135.498679]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90
>>>
>>> [  135.498686]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730
>>>
>>> [  135.498698]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70
>>>
>>> [  135.498703]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0
>>>
>>> [  135.498710]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0
>>>
>>> [  135.498715]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0
>>>
>>> [  135.498722]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0
>>>
>>> [  135.498728]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370
>>>
>>> [  135.498733]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0
>>>
>>> [  135.498738]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20
>>>
>>> [  135.498839]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90
>>>
>>> [  135.498845]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b
>>>
>>> [  135.498848] ---[ end trace e1dd916182de3a9d ]---
>>>
>>> [  135.498851] ------------[ cut here ]------------
>>>
>>> [  135.498871] WARNING: CPU: 1 PID: 2346 at fs/btrfs/send.c:5951
>>> btrfs_ioctl_send+0x28f/0x11e0 [btrfs]()
>>>
>>> [  135.498894] Modules linked in: nf_conntrack_ipv4(E)
>>> nf_defrag_ipv4(E) xt_conntrack(E) nf_conntrack(E) ipt_REJECT(E)
>>> nf_reject_ipv4(E) xt_tcpudp(E) iptable_filter(E) ip_tables(E)
>>> x_tables(E) bridge(E) stp(E) llc(E) snd_intel8x0(E) snd_ac97_codec(E)
>>> ac97_bus(E) snd_pcm(E) snd_timer(E) snd(E) iosf_mbi(E) soundcore(E)
>>> ppdev(E) joydev(E) lp(E) serio_raw(E) parport_pc(E) i2c_piix4(E)
>>> mac_hid(E) parport(E) btrfs(E) xor(E) raid6_pq(E) hid_generic(E)
>>> usbhid(E) hid(E) ahci(E) psmouse(E) libahci(E) e1000(E) pata_acpi(E)
>>>
>>> [  135.498900] CPU: 1 PID: 2346 Comm: btrfs Tainted: G     W   E
>>> 4.0.0-rc4-custom #3
>>>
>>> [  135.498903] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
>>> VirtualBox 12/01/2006
>>>
>>> [  135.498910]  ffffffffc0509016 ffff88007a233c08 ffffffff817b62f3
>>> 000000004c724c72
>>>
>>> [  135.498918]  0000000000000000 ffff88007a233c48 ffffffff8107452a
>>> ffff88007a233c38
>>>
>>> [  135.498923]  ffff8800799f1400 ffff880078d52cc0 ffff880078d52cd8
>>> ffff8800799f15d8
>>>
>>> [  135.498927] Call Trace:
>>>
>>> [  135.498937]  [<ffffffff817b62f3>] dump_stack+0x45/0x57
>>>
>>> [  135.498945]  [<ffffffff8107452a>] warn_slowpath_common+0x8a/0xc0
>>>
>>> [  135.498951]  [<ffffffff8107461a>] warn_slowpath_null+0x1a/0x20
>>>
>>> [  135.498975]  [<ffffffffc04f52af>] btrfs_ioctl_send+0x28f/0x11e0 [btrfs]
>>>
>>> [  135.498984]  [<ffffffff8118020e>] ? __alloc_pages_nodemask+0x1ae/0xab0
>>>
>>> [  135.498990]  [<ffffffff810a4775>] ? sched_clock_local+0x25/0x90
>>>
>>> [  135.498996]  [<ffffffff8109182e>] ? alloc_pid+0x2e/0x530
>>>
>>> [  135.499023]  [<ffffffffc04bc4f6>] btrfs_ioctl+0x286/0x27e0 [btrfs]
>>>
>>> [  135.499031]  [<ffffffff810a6368>] ? __enqueue_entity+0x78/0x80
>>>
>>> [  135.499037]  [<ffffffff810add70>] ? enqueue_entity+0x400/0xc20
>>>
>>> [  135.499046]  [<ffffffff8101dc3a>] ? native_sched_clock+0x2a/0x90
>>>
>>> [  135.499055]  [<ffffffff810ae708>] ? enqueue_task_fair+0x178/0x730
>>>
>>> [  135.499061]  [<ffffffff81047c1d>] ? native_smp_send_reschedule+0x4d/0x70
>>>
>>> [  135.499069]  [<ffffffff8109d5f0>] ? resched_curr+0x70/0xc0
>>>
>>> [  135.499078]  [<ffffffff8109e12a>] ? check_preempt_curr+0x5a/0xa0
>>>
>>> [  135.499087]  [<ffffffff810a152f>] ? wake_up_new_task+0x12f/0x1b0
>>>
>>> [  135.499096]  [<ffffffff81204010>] do_vfs_ioctl+0x2e0/0x4e0
>>>
>>> [  135.499106]  [<ffffffff8107368c>] ? do_fork+0x13c/0x370
>>>
>>> [  135.499115]  [<ffffffff81204291>] SyS_ioctl+0x81/0xa0
>>>
>>> [  135.499121]  [<ffffffff81073946>] ? SyS_clone+0x16/0x20
>>>
>>> [  135.499131]  [<ffffffff817bd80d>] ? stub_clone+0x6d/0x90
>>>
>>> [  135.499140]  [<ffffffff817bd50d>] system_call_fastpath+0x16/0x1b
>>>
>>> [  135.499144] ---[ end trace e1dd916182de3a9e ]---
>>
>>
>>
>> --
>> Filipe David Manana,
>>
>> "Reasonable men adapt themselves to the world.
>>  Unreasonable men adapt the world to themselves.
>>  That's why all progress depends on unreasonable men."



-- 
Filipe David Manana,

"Reasonable men adapt themselves to the world.
 Unreasonable men adapt the world to themselves.
 That's why all progress depends on unreasonable men."