btrfs-progs: fsck-tests: Introduce test case with keyed data backref with the extent offset
Add the testcase for false alert of data extent backref lost with the
extent offset.
The image can be reproduced by the following commands:
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dev=~/test.img
mnt=/mnt/btrfs
umount $mnt &> /dev/null
fallocate -l 128M $dev
mkfs.btrfs $dev
mount $dev $mnt
for i in `seq 1 10`; do
xfs_io -f -c "pwrite 0 2K" $mnt/file$i
done
xfs_io -f -c "falloc 0 64K" $mnt/file11
for i in `seq 1 32`; do
xfs_io -f -c "reflink $mnt/file11 0 $(($i * 64))K 64K" $mnt/file11
done
xfs_io -f -c "reflink $mnt/file11 32K $((33 * 64))K 32K" $mnt/file11
btrfs subvolume snapshot $mnt $mnt/snap1
umount $mnt
btrfs-image -c9 $dev extent_data_ref.img
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Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>