File operation on removed USB memory stick

File operation on removed USB memory stick

[Joaquim Duran]

Dear all,

I'm new to this e-mail list. My name is Joaquim Duran.

I've detected a behavior of the SCSI system that could be improved when
accessing to a removed USB memory stick.

That is, I was playing musing from a mounted USB stick, then I removed
it while the program was still running. The program stopped with an
error after few seconds. I checked the message log file and saw that the
I/O operations to a file of the memory stick were done 3 times before
notify the fault to the application. The logs:

Jan 23 09:36:47 adlab127 sdf: sdf1
Jan 23 09:36:47 adlab127 sd 2:0:0:0: [sdf] Attached SCSI removable disk
Jan 23 09:36:47 adlab127 sd 2:0:0:0: Attached scsi generic sg4 type 0
Jan 23 09:36:47 adlab127 usb-storage: device scan complete
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 127) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 128) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 129) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 130) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 131) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 132) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 133) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 134) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 127) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 128) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 129) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 130) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 131) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 132) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 133) failed
Jan 23 09:36:47 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:47 adlab127 FAT: Directory bread(block 134) failed
Jan 23 09:36:58 adlab127 scsi 1:0:0:0: rejecting I/O to dead device
Jan 23 09:36:58 adlab127 FAT: unable to read inode block for updating
(i_pos 7582155)

If the memory stick has been removed, a more severe error could be
notified to the application avoiding the repetition of the operations.

In general IMHO, the behavior to this situation would be:

1 - Move all cache blocks of the removed memory USB stick to the free list.

2 - Any operation relating to the removed device be notified as a severe
error avoiding repetitions.

because if the USB stick is removed in inserted once again it will be
mounted as a different device that the current one, because as still
there is files in use, the device could not be unmounted from system.

Thanks and Best Regards,
Joaquim Duran