fio direct I/O error with 1k blocksize

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When to run fio write with small blocksize(e.g. 1k), the following error is seen.

$ fio --blocksize=1k --ioengine=libaio --readwrite=randwrite --filesize=2G --group_reporting --direct=1 --iodepth=128 --randrepeat=1 --end_fsync=1 --
name=job1 --numjobs=1 --filename=/mnt/fiomnt/fio.dat
job1: (g=0): rw=randwrite, bs=(R) 1024B-1024B, (W) 1024B-1024B, (T) 1024B-1024B, ioengine=libaio, iodepth=128
fio-3.7
Starting 1 process
fio: io_u error on file /mnt/fiomnt/fio.dat: Invalid argument: write offset=129521664, buflen=1024
fio: io_u error on file /mnt/fiomnt/fio.dat: Invalid argument: write offset=1589760000, buflen=1024
fio: pid=93922, err=22/file:io_u.c:1747, func=io_u error, error=Invalid argument
job1: (groupid=0, jobs=1): err=22 (file:io_u.c:1747, func=io_u error, error=Invalid argument): pid=93922: Wed Jan 25 00:42:00 2023
cpu : usr=0.00%, sys=0.00%, ctx=1, majf=0, minf=14
IO depths : 1=0.8%, 2=1.6%, 4=3.1%, 8=6.2%, 16=12.5%, 32=25.0%, >=64=50.8%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued rwts: total=0,128,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=128

Cause:

For direct I/O,  the I/O size has to be multiple of filesystem/block device blocksize. In this case, the filesystem blocksize is 4k which can not be well aligned with the requested I/O size(1k). To fix this, the filesystem blocksize should be less than or equal to 1k.