--- /dev/null
+#! /bin/bash
+# FS QA Test No. 059
+#
+# This test is motivated by an fsync issue discovered in btrfs.
+# The issue was that after punching a hole for a small range, which affected
+# only a partial page, an fsync operation would have no effect at all. This was
+# because for this particular case the btrfs hole punching implementation did
+# not update some btrfs specific inode metadata that is required to determine
+# if an fsync operation needs to update the fsync log. For this to happen, it
+# was also necessary that in the transaction where the hole punching was
+# performed, and before the fsync operation, no other operation that modified
+# the file (or its metadata) was performed.
+#
+# The btrfs issue was fixed by the following linux kernel patch:
+#
+# Btrfs: add missing inode update when punching hole
+#
+#-----------------------------------------------------------------------
+# Copyright (C) 2015 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"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1 # failure is the default!
+
+_cleanup()
+{
+ _cleanup_flakey
+ rm -f $tmp.*
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/dmflakey
+
+# real QA test starts here
+_supported_fs generic
+_supported_os Linux
+_need_to_be_root
+_require_scratch
+_require_dm_flakey
+_require_xfs_io_command "fpunch"
+
+rm -f $seqres.full
+
+_scratch_mkfs >> $seqres.full 2>&1
+_init_flakey
+_mount_flakey
+
+# Create our test file.
+$XFS_IO_PROG -f -c "pwrite -S 0x22 -b 16K 0 16K" \
+ $SCRATCH_MNT/foo | _filter_xfs_io
+
+# Fsync the file, this makes btrfs update some btrfs inode specific fields
+# that are used to track if the inode needs to be written/updated to the fsync
+# log or not. After this fsync, the new values for those fields indicate that
+# a subsequent fsync does not need to touch the fsync log.
+$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
+
+# Force a commit of the current transaction. After this point, any operation
+# that modifies the data or metadata of our file, should update those fields in
+# the btrfs inode with values that make the next fsync operation write to the
+# fsync log.
+sync
+
+# Punch a hole in our file. This small range affects only 1 page.
+# This made the btrfs hole punching implementation write only some zeroes in
+# one page, but it did not update the btrfs inode fields used to determine if
+# the next fsync needs to write to the fsync log.
+$XFS_IO_PROG -c "fpunch 8000 4K" $SCRATCH_MNT/foo
+
+# Another variation of the previously mentioned case.
+$XFS_IO_PROG -c "fpunch 15000 100" $SCRATCH_MNT/foo
+
+# Now fsync the file. This was a no-operation because the previous hole punch
+# operation didn't update the inode's fields mentioned before, so they remained
+# with the values they had after the first fsync - that is, they indicate that
+# it is not needed to write to fsync log.
+$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
+
+echo "File content before:"
+od -t x1 $SCRATCH_MNT/foo
+
+# Simulate a crash/power loss.
+_load_flakey_table $FLAKEY_DROP_WRITES
+_unmount_flakey
+
+# Enable writes and mount the fs. This makes the fsync log replay code run.
+_load_flakey_table $FLAKEY_ALLOW_WRITES
+_mount_flakey
+
+# Because the last fsync didn't do anything, here the file content matched what
+# it was after the first fsync, before the holes were punched, and not what it
+# was after the holes were punched.
+echo "File content after:"
+od -t x1 $SCRATCH_MNT/foo
+
+status=0
+exit
--- /dev/null
+QA output created by 059
+wrote 16384/16384 bytes at offset 0
+XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+File content before:
+0000000 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
+*
+0017500 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+*
+0027500 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
+*
+0035220 22 22 22 22 22 22 22 22 00 00 00 00 00 00 00 00
+0035240 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+*
+0035360 00 00 00 00 00 00 00 00 00 00 00 00 22 22 22 22
+0035400 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
+*
+0040000
+File content after:
+0000000 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
+*
+0017500 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+*
+0027500 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
+*
+0035220 22 22 22 22 22 22 22 22 00 00 00 00 00 00 00 00
+0035240 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+*
+0035360 00 00 00 00 00 00 00 00 00 00 00 00 22 22 22 22
+0035400 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
+*
+0040000
projects / xfstests-dev.git / commitdiff