On Fri, Mar 23, 2012 at 4:21 PM, Mike Snitzer <snitzer@xxxxxxxxxx> wrote: > On Fri, Mar 23 2012 at 10:12am -0400, > Kasatkin, Dmitry <dmitry.kasatkin@xxxxxxxxx> wrote: > >> On Fri, Mar 23, 2012 at 1:26 PM, Kasatkin, Dmitry >> <dmitry.kasatkin@xxxxxxxxx> wrote: >> > On Fri, Mar 23, 2012 at 1:10 PM, Zdenek Kabelac <zkabelac@xxxxxxxxxx> wrote: >> >> Dne 23.3.2012 12:01, Kasatkin, Dmitry napsal(a): >> >>> Hello, >> >>> >> >>> When using dm-bufio and dm-io in general, how to ensure that all dirty >> >>> buffers are written to the storage when machine reboots? >> >>> suspend hooks could be used, but they are not called on reboot, only >> >>> when suspending/removing the target... >> >>> >> >> >> >> You mean you reboot without running 'sync' command? >> >> >> >> And yes - on reboot you should properly unmount devices - so you should >> >> see removal of target on your shutdown sequence - I believe Fedora currently >> >> tries to support switch to some shutdown ramdisk, so all filesystem and >> >> devices might be properly unmounted and destroyed. >> >> >> > >> > Hello, >> > >> > Thanks for response. >> > I use bufio to store some data on block device. >> > It is not mounted in anyway. My target just use it to load/store data. >> > When machine reboots, I want to be sure that bufio written all dirty buffers... >> > >> > - Dmitry >> > >> >> At the moment, I have reboot notifier which does the following >> >> dm_bufio_write_dirty_buffers(d->bufio); >> sync_blockdev(d->dev->bdev); >> blkdev_issue_flush(d->dev->bdev, GFP_KERNEL, NULL); >> >> without first line on the next boot I got corrupted/not updated blocks. >> and I am not sure if I need last 2 lines... > > Are you cleanly removing the target from the kernel before reboot > (e.g. dmsetup remove devname)? > > As long as your target's .dtr is making sure to flush all outstanding IO > (like your reboot notifier does) you should be fine. > The target contains rootfs... On reboot, it is remounted read-only. I cannot remove it... Sometime ago I had "message" operation "sync", to sync backing devices. But reboot notifier looks nice... It is automatically called. > -- > dm-devel mailing list > dm-devel@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/dm-devel -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
