On Thu, Sep 24, 2015 at 09:06:32PM +0300, Matwey V. Kornilov wrote: > I would like to read the list of the checksums for the specific file > stored onto btrfs filesystem. I think I could use the checksums in the > manner like rsync does, but safe both CPU (because csums are already > calculated for the file) and I/O (because I don't need to reread all the > file from the hard drive). > > I've looked through linux kernel sources and not found appropriate ioctl > to do this. Frankly speaking, I've not found good documentations for all > available btrfs ioctls. I have the ioctl docs in my todo and barely started it. There's no single ioctl for getting the per-block checksums but it is possible using several calls to the SEARCH_TREE. I have a prototype in my gits in branch dev/block-csum-search (2nd patch from the top), I'll try to find some time to make it a proper subcommand, so far the command UI is not righ enough and the output is quite rough. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
