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+#! /bin/bash
+# FS QA Test No. btrfs/124
+#
+# Test that an incremental send operation works after doing radical changes
+# in the directory hierarchy that involve switching the inode that directory
+# entries point to.
+#
+#-----------------------------------------------------------------------
+# Copyright (C) 2016 SUSE Linux Products GmbH. All Rights Reserved.
+# Author: Filipe Manana <fdmanana@suse.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+#-----------------------------------------------------------------------
+#
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+tmp=/tmp/$$
+status=1 # failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+ cd /
+ rm -fr $send_files_dir
+ rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# real QA test starts here
+_supported_fs btrfs
+_supported_os Linux
+_require_scratch
+_require_test
+_require_fssum
+
+send_files_dir=$TEST_DIR/btrfs-test-$seq
+
+rm -f $seqres.full
+rm -fr $send_files_dir
+mkdir $send_files_dir
+
+_scratch_mkfs >>$seqres.full 2>&1
+_scratch_mount
+
+# case 1
+mkdir -p $SCRATCH_MNT/case_1/d/p1
+mkdir $SCRATCH_MNT/case_1/p1
+
+# case 2
+mkdir -p $SCRATCH_MNT/case_2/a
+mkdir $SCRATCH_MNT/case_2/d
+mkdir $SCRATCH_MNT/case_2/e
+mkdir $SCRATCH_MNT/case_2/f
+mkdir $SCRATCH_MNT/case_2/ance
+mkdir $SCRATCH_MNT/case_2/d/ance
+mkdir $SCRATCH_MNT/case_2/a/c
+mv $SCRATCH_MNT/case_2/e $SCRATCH_MNT/case_2/d/ance
+mv $SCRATCH_MNT/case_2/f $SCRATCH_MNT/case_2/d/ance
+mv $SCRATCH_MNT/case_2/ance $SCRATCH_MNT/case_2/d/ance
+
+# case 3
+mkdir -p $SCRATCH_MNT/case_3/d
+mkdir $SCRATCH_MNT/case_3/a
+mkdir $SCRATCH_MNT/case_3/waiting_dir
+mkdir -p $SCRATCH_MNT/case_3/pre/ance
+mkdir $SCRATCH_MNT/case_3/d/ance
+mkdir $SCRATCH_MNT/case_3/a/c
+mv $SCRATCH_MNT/case_3/waiting_dir $SCRATCH_MNT/case_3/d/ance
+
+# case 4
+mkdir -p $SCRATCH_MNT/case_4/tmp
+mkdir $SCRATCH_MNT/case_4/below_ance
+mkdir -p $SCRATCH_MNT/case_4/pre/wait_dir
+mkdir $SCRATCH_MNT/case_4/desc
+mkdir $SCRATCH_MNT/case_4/ance
+mv $SCRATCH_MNT/case_4/below_ance $SCRATCH_MNT/case_4/ance
+mkdir $SCRATCH_MNT/case_4/other_dir
+
+# Filesystem looks like:
+#
+# . (ino 256)
+# |--- case_1/ (ino 257)
+# | |---- d/ (ino 258)
+# | | |--- p1/ (ino 259)
+# | |
+# | |---- p1/ (ino 260)
+# |
+# |--- case_2/ (ino 261)
+# | |---- a/ (ino 262)
+# | | |---- c/ (ino 268)
+# | |
+# | |---- d/ (ino 263)
+# | |---- ance/ (ino 267)
+# | |---- e/ (ino 264)
+# | |---- f/ (ino 265)
+# | |---- ance/ (ino 266)
+# |
+# |--- case_3/ (ino 269)
+# | |---- a/ (ino 271)
+# | | |---- c/ (ino 276)
+# | |
+# | |---- d/ (ino 270)
+# | | |---- ance/ (ino 275)
+# | | |---- waiting_dir/ (ino 272)
+# | |
+# | |---- pre/ (ino 273)
+# | |---- ance/ (ino 274)
+# |
+# |--- case_4/ (ino 277)
+# |---- tmp/ (ino 278)
+# |---- pre/ (ino 280)
+# | |---- wait_dir/ (ino 281)
+# |
+# |---- desc/ (ino 282)
+# |---- ance/ (ino 283)
+# | |---- below_ance/ (ino 279)
+# |
+# |---- other_dir/ (ino 284)
+#
+_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap1
+
+# case 1
+#
+# The directory named "d" (inode 257) has in both snapshots an entry with the
+# name "p1" but it refers to different inodes in both snapshots (inode 258 in
+# the parent snapshot and inode 259 in the send snapshot). When attempting to
+# move inode 258, the operation is delayed because its new parent, inode 259,
+# was not yet moved/renamed (as the stream is currently processing inode 258).
+# Later on when processing inode 259, btrfs' send also ended up delaying the
+# move/rename operation for this inode, so that it would happen after inode 258
+# was processed, creating a circular dependency that resulted in the send stream
+# terminating without issuing a rename operations for the inodes 258 and 259.
+#
+mv $SCRATCH_MNT/case_1/d/p1 $SCRATCH_MNT/case_1/p1
+mv $SCRATCH_MNT/case_1/p1 $SCRATCH_MNT/case_1/d
+
+# case 2
+#
+# When the inode 265 is processed, the path for inode 267 is computed, which at
+# that time corresponds to "case_2/d/ance", and it was stored in the name cache
+# (to avoid recomputing it again later when needed).
+# Later on when processing inode 266, btrfs' send end up orphanizing (renaming
+# to a name matching the pattern o<ino>-<gen>-<seq>) inode 267 because it has
+# the same name as inode 266 and at that time it's a child of the new parent
+# directory (inode 263) for inode 266. After the orphanization and while still
+# processing inode 266, a rename operation for inode 266 was generated. However
+# the source path for that rename operation was incorrect because it ended up
+# using the old, pre-orphanization, name of inode 267.
+#
+mv $SCRATCH_MNT/case_2/a/c $SCRATCH_MNT/case_2
+mv $SCRATCH_MNT/case_2/d/ance $SCRATCH_MNT/case_2/c
+mv $SCRATCH_MNT/case_2/c/ance/ance $SCRATCH_MNT/case_2/d
+mv $SCRATCH_MNT/case_2/c/ance/f $SCRATCH_MNT/case_2
+mv $SCRATCH_MNT/case_2/c/ance/e $SCRATCH_MNT/case_2/f
+
+# case 3
+#
+# This is similar to cases 1 and 2, but adding more complexity just to exercise
+# btrfs' incremental send correctness.
+#
+mv $SCRATCH_MNT/case_3/d/ance $SCRATCH_MNT/case_3/a
+mv $SCRATCH_MNT/case_3/a/c $SCRATCH_MNT/case_3
+mv $SCRATCH_MNT/case_3/a/ance/waiting_dir $SCRATCH_MNT/case_3/c
+mv $SCRATCH_MNT/case_3/pre/ance $SCRATCH_MNT/case_3/d
+mv $SCRATCH_MNT/case_3/pre $SCRATCH_MNT/case_3/c/waiting_dir
+
+# case 4
+#
+# When attempting to rename inode 283, the incremental send stream included an
+# invalid destination path for the rename command. This was due to a missing
+# path loop detection in the send code that made the rename of inode 283 happen
+# without waiting for the rename of inode 284 to happen first (since it's an
+# ancestor in the send snapshot that is beyond the current progress and it was
+# also renamed/moved).
+#
+mv $SCRATCH_MNT/case_4/other_dir $SCRATCH_MNT/case_4/tmp
+mv $SCRATCH_MNT/case_4/ance/below_ance $SCRATCH_MNT/case_4/tmp/other_dir
+mv $SCRATCH_MNT/case_4/pre/wait_dir $SCRATCH_MNT/case_4/tmp/other_dir
+mv $SCRATCH_MNT/case_4/pre $SCRATCH_MNT/case_4/tmp/other_dir/below_ance
+mv $SCRATCH_MNT/case_4/desc $SCRATCH_MNT/case_4/tmp/other_dir/wait_dir
+mv $SCRATCH_MNT/case_4/ance $SCRATCH_MNT/case_4/tmp/other_dir/wait_dir/desc
+
+# Filesystem now looks like:
+#
+# . (ino 256)
+# |--- case_1/ (ino 257)
+# | |--- d/ (ino 258)
+# | |--- p1/ (ino 260)
+# | |--- p1/ (ino 259)
+# |
+# |--- case_2/ (ino 261)
+# | |---- a/ (ino 262)
+# | |---- c/ (ino 268)
+# | | |---- ance/ (ino 267)
+# | |
+# | |---- d/ (ino 263)
+# | | |---- ance/ (ino 266)
+# | |
+# | |---- f/ (ino 265)
+# | |---- e/ (ino 264)
+# |
+# |--- case_3/ (ino 269)
+# | |---- a/ (ino 271)
+# | | |---- ance/ (ino 275)
+# | |
+# | |---- c/ (ino 276)
+# | | |---- waiting_dir/ (ino 272)
+# | | |---- pre/ (ino 273)
+# | |
+# | |---- d/ (ino 270)
+# | |---- ance/ (ino 274)
+# |
+# |--- case_4/ (ino 277)
+# |---- tmp/ (ino 278)
+# |---- other_dir/ (ino 284)
+# |---- below_ance/ (ino 279)
+# | |---- pre/ (ino 280)
+# |
+# |---- wait_dir/ (ino 281)
+# |---- desc/ (ino 282)
+# |---- ance/ (ino 283)
+#
+_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2
+
+run_check $FSSUM_PROG -A -f -w $send_files_dir/1.fssum $SCRATCH_MNT/mysnap1
+run_check $FSSUM_PROG -A -f -w $send_files_dir/2.fssum \
+ -x $SCRATCH_MNT/mysnap2/mysnap1 $SCRATCH_MNT/mysnap2
+
+_run_btrfs_util_prog send $SCRATCH_MNT/mysnap1 -f $send_files_dir/1.snap
+_run_btrfs_util_prog send -p $SCRATCH_MNT/mysnap1 $SCRATCH_MNT/mysnap2 \
+ -f $send_files_dir/2.snap
+
+# Now recreate the filesystem by receiving both send streams and verify we get
+# the same content that the original filesystem had.
+_scratch_unmount
+_scratch_mkfs >>$seqres.full 2>&1
+_scratch_mount
+
+_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/1.snap
+run_check $FSSUM_PROG -r $send_files_dir/1.fssum $SCRATCH_MNT/mysnap1
+_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/2.snap
+run_check $FSSUM_PROG -r $send_files_dir/2.fssum $SCRATCH_MNT/mysnap2
+
+echo "Silence is golden"
+status=0
+exit
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+QA output created by 124
+Silence is golden
@@ -126,3 +126,4 @@
121 auto quick snapshot qgroup
122 auto quick snapshot qgroup
123 auto quick qgroup
+124 auto quick send