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>
0155481cc9