Alberto Bertogli <albertito@xxxxxxxxxxxxxx> writes: > Hi! > > I'm writing this device mapper target that stores checksums on writes and > verifies them on reads. > > It's not widely tested, but you can run mke2fs on it and do basic file > operations. The to-do list is still large, and most of it can be found within > the code. > > To test it, you will need to format the device using the (very rough) attached > tool, and then create the dm device with something like: > > echo 0 $SIZE csum $REALDEVICE 0 | dmsetup create $NAME > > > I think it can be useful for people who want to detect data corruption and are > either using the block layer directly or a filesystem that doesn't check data > integrity (which are most, if not all, of the popular ones today). Maybe it > could also be used for testing the bio-integrity extensions, although at the > moment it's completely independent and I haven't looked much, but it's on my > to-do list. > > It does NOT pretend to be useful for consistency checks for security purposes. > Use something else if you do not want someone evil tampering with your data. > > > Comments are obviously welcome. There are also some questions embedded in the > code, if anyone cares to answer any of them, I'd really appreciate it. > > Thanks a lot, > Alberto How does that behave on crashes? Will checksums be out of sync with data? Will pending blocks recalculate their checksum? MfG Goswin -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel