xfstests 240: test non-aligned AIO hole-filling
This replicates file corruption we've seen with qemu-kvm when
we use if=virtio,cache=none,aio=native for IO to a sparse
ext4- or xfs-hosted file, and the partitions/filesystems
within that file image are not block-aligned. (think sector
63 here...) This results in AIO IOs not aligned to the
filesystem blocks.
This test modifies aiodio_sparse2.c to add an option to start
the file IO at an offset.
When we do 4k writes to a 16k file in 2 threads, starting
at offset 512, we get 0s interspersed in the file where they
should not be:
00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00000200 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 |................|
*
00001000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00001200 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 |................|
....
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Dave Chinner <dchinner@redhat.com>