Ping? On Thu, Oct 31, 2013 at 12:00:41PM -0200, Carlos Maiolino wrote: > Hi guys, my apologies to have not touched this conversation for a while, got > busy with other stuff. > > So, let me continue this. > > On Wed, Jan 23, 2013 at 02:00:37PM +0100, Jan Kara wrote: > > On Wed 23-01-13 07:22:49, Carlos Maiolino wrote: > > > On Wed, Jan 23, 2013 at 11:39:17AM +0100, Jan Kara wrote: > > > > On Tue 22-01-13 11:07:58, Carlos Maiolino wrote: > > > > > This checks for incompatible mounting options when using ext4 module to mount > > > > > ext3 or ext2 filesystems. > > > > > > > > > > Sets two new flags to group ext4 mount options that are incompatible with ext2 > > > > > and ext3, and then add two functions -- check_ext2/3_incompat_mount() -- to > > > > > check and warn/fail mount, if any of these options are being used. > > > > > > > > > > I believe, some options like those expecting an argument needs to be checked > > > > > during parsing time. > > > > > > > > > > barrier mount, although it has a flag, when mounting an ext2fs, where > > > > > barriers are not supported (afaik), should also be checked during parse > > > > > time, otherwise the BARRIER mount flag will be set. > > > > > > > > > > I didn't add all mount options I believe to need to raise a warning, just > > > > > those with a flag set on superblock, another flags should be added after a > > > > > discussion to reach a concensus of all ext2/3 options that should be rejected by > > > > > ext4 mount. > > > > Thinking about it a bit more I'm not sure if restricting mount options is > > > > the right thing to start with. IMHO what we should restrict is mounting > > > > filesystem with certain *features* as ext3/ext2. So e.g. filesystem with > > > > EXT4_FEATURE_INCOMPAT_EXTENTS cannot be mounted as ext2 or ext3. Similarly > > > > as currently we forbid mounting ext3 filesystem with > > > > EXT3_FEATURE_INCOMPAT_RECOVER as ext2... This should avoid the confusion > > > > which could arise when someone reports problems with "ext3" filesystem but > > > > actually has some of the ext4 features enabled. > > > > > > > This is interesting, but I wonder if not restricting mount options, but > > > features, would open a 'window' to let users change their filesystem on-disk > > > format without know what they are doing, but I might be wrong. > > If there are mount options that enable features, then these should be > > disallowed for ext2/ext3 mounts. But I think we already got rid of these > > traps on users... > > > > Honza > > -- > > Jan Kara <jack@xxxxxxx> > > SUSE Labs, CR > > Jan, I agree with the idea of check for incompat features and I can work on that > with no problem, but I still think we need to also ensure some mount options are > not allowed to be used with some specific ExtFS versions wheter it change the > disk format (we probably got rid of these as you said) or not. Not sure if my > previous (V2) to restrict mount options lacks something or need to be reworked > in some way (of course now it should to fit new kernel versions). > > As an example, commit=<secs> option doesn't make sense to be used on ext2 > filesystems, but you can mount an ext2 FS with this option with no problem. > > > -- > Carlos > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Carlos -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
