Mad Hatter testifies - the small bio-s joining in

• Each I/O may have been split into several smaller I/O requests.
• This could have been because the original I/O was too big, or due to being split across several devices (software-RAID, LVM), etc.
• Each small I/O that returns - has a status.
• The status of the original I/O will be "success" - only if all the underlying I/O requests succeeded.
• Hopefully, the testimony accuracy is better than that of the Mad Hatter...

Originally written by guy keren