virtio-blk: emit udev event when device is resized
authorMilos Vyletel <milos.vyletel@sde.cz>
Tue, 12 Mar 2013 05:04:40 +0000 (15:34 +1030)
committerRusty Russell <rusty@rustcorp.com.au>
Tue, 12 Mar 2013 05:14:55 +0000 (15:44 +1030)
commit9d9598b81c5c05495009e81ac0508ec8d1558015
treebd4b367e3332908f0a1111e743efce3006e9ed43
parentba06d1e1d3350a38476ea6b7655ba7c047baad67
virtio-blk: emit udev event when device is resized

When virtio-blk device is resized from host (using block_resize from QEMU) emit
KOBJ_CHANGE uevent to notify guest about such change. This allows user to have
custom udev rules which would take whatever action if such event occurs. As a
proof of concept I've created simple udev rule that automatically resize
filesystem on virtio-blk device.

ACTION=="change", KERNEL=="vd*", \
        ENV{RESIZE}=="1", \
        ENV{ID_FS_TYPE}=="ext[3-4]", \
        RUN+="/sbin/resize2fs /dev/%k"
ACTION=="change", KERNEL=="vd*", \
        ENV{RESIZE}=="1", \
        ENV{ID_FS_TYPE}=="LVM2_member", \
        RUN+="/sbin/pvresize /dev/%k"

Signed-off-by: Milos Vyletel <milos.vyletel@sde.cz>
Tested-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (minor simplification)
drivers/block/virtio_blk.c