On Wed, Apr 04, 2012 at 02:16:22PM -0400, Josef Bacik wrote: > On Wed, Apr 04, 2012 at 09:12:57PM +0300, Kasatkin, Dmitry wrote: > > On Wed, Apr 4, 2012 at 8:47 PM, Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx> wrote: > > > On Wed, 2012-04-04 at 13:43 -0400, Josef Bacik wrote: > > >> On Wed, Apr 04, 2012 at 08:24:19PM +0300, Kasatkin, Dmitry wrote: > > >> > Hello, > > >> > > > >> > Mimi and I working on IMA/EVM (security/integrity) and it uses > > >> > i_version for checking if file content has been changed. > > >> > extX file systems support i_version updates with mounting file system > > >> > with "iversion" option or via kernel command line parameter > > >> > "i_version" > > >> > > > >> > It seems iversion option is not recognized when mounting btrfs. > > >> > I see this patchset deals with i_version update as well.. > > >> > Can you please give an advice how to use i_version with btrfs? > > >> > > > >> > > >> Oh good somebody uses this? We actually have a ->sequence thing we use for > > >> this, the grand idea was to make it smarter about telling nfs when something > > >> changed, but if you guys use i_version we could probably get rid of our in-core > > >> sequence and use the normal inodes i_version and then just store it in our > > >> sequence field on disk. I'll do it without a mount option tho so it just works, > > >> does that sound good to you? Thanks, > > > > Hello, > > > > Thank you for the answer... > > But can you a bit clarify... > > > > Looking to file_update_time() I see that it does: > > > > if (IS_I_VERSION(inode)) > > sync_it |= S_VERSION; > > > > Basically it should be (inode->i_sb->s_flags & MS_I_VERSION) > > > > use of i_version is controlled by iversion mount flag. > > for ext4 I see in parse_options(): > > > > case Opt_i_version: > > set_opt(sb, I_VERSION); > > sb->s_flags |= MS_I_VERSION; > > break; > > > > > > But who sets MS_I_VERSION in s_flags on btrfs? > > > > Nobody yet, I'm going to send a patch shortly that will support this. Thanks, Great. It would also be far preferable if it was just always on (at least by default) rather than requiring a mount option. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
