From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Subject: Re: [PATCH] virtio-blk: emit udev event when device is resized Date: Fri, 22 Feb 2013 10:14:49 +1030 Message-ID: <87y5ehfczy.fsf@rustcorp.com.au> References: <1361473348-7660-1-git-send-email-milos.vyletel@sde.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1361473348-7660-1-git-send-email-milos.vyletel@sde.cz> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: linux-kernel@vger.kernel.org Cc: Greg KH , mst@redhat.com, Milos Vyletel , virtualization@lists.linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org Milos Vyletel writes: > 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" This looks fine to me, but I like to check with Greg before adding udev callouts.... Greg? BTW, if this is good, it's good for stable IMHO. Cheers, Rusty. > Signed-off-by: Milos Vyletel > --- > drivers/block/virtio_blk.c | 3 +++ > 1 files changed, 3 insertions(+), 0 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index 8ad21a2..5990382 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -539,6 +539,8 @@ static void virtblk_config_changed_work(struct work_struct *work) > struct virtio_device *vdev = vblk->vdev; > struct request_queue *q = vblk->disk->queue; > char cap_str_2[10], cap_str_10[10]; > + char event[] = "RESIZE=1"; > + char *envp[] = { event, NULL }; > u64 capacity, size; > > mutex_lock(&vblk->config_lock); > @@ -568,6 +570,7 @@ static void virtblk_config_changed_work(struct work_struct *work) > > set_capacity(vblk->disk, capacity); > revalidate_disk(vblk->disk); > + kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp); > done: > mutex_unlock(&vblk->config_lock); > } > -- > 1.7.1