On Sun, Apr 12, 2009 at 07:35, David Zeuthen <zeut...@gmail.com> wrote:
> But we'd still need some kind of way of having the kernel tell user > space what devices are currently claimed by the btrfs filesystem > instance (and we'd need notifications on changes too). Otherwise we > don't have enough information for the desktop shell and partitioning > programs to let the user know that /dev/sdb2 or /dev/sdc1 or whatever > is currently claimed by the 0:19 btrfs mount at /media/fedora-usb. > > One idea is to have a pollable file, /proc/fs/btrfs/devs, that maps > from the dev_t of the btrfs filesystem instance (as used in > /proc/self/mountinfo) to the set of dev_t for block devices currently > claimed? E.g. for the example above we'd have > > /proc/fs/btrfs/devs: > 0:19 8:18 Btrfs used to export some information in /sys/fs/btrfs/, this is disabled for now. Maybe we can possibly make it export something like: $ tree /sys/fs/btrfs/ /sys/fs/btrfs/ |-- 969d1386-a002-4c28-94f2-47be23f344e4 | |-- ba1532f3-849b-400b-9c76-2c9aee126c52 | | |-- device -> ../../../devices/.../block/sda/sda3 | | |-- attribute1 | | |-- ... | `-- 45645656-849b-400b-9c76-2c9aee126c52 | |-- device -> ../../../devices/.../block/sdb/sdb3 | |-- attribute1 | .... `-- 645645686-a002-4c28-94f2-47be23f344e4 |-- ... So you could look for a "device" link at the subvolume devices? Or if that does not fit for some reason, we could also add a "btrfs" class, to export details about the subvolumes. Thanks, Kay -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html