On Wed, Mar 7, 2018 at 2:52 PM, Chengguang Xu <cgxu519@xxxxxxx> wrote: > Hello folks, > > Recently I'm trying to implement a feature on overlayfs for our users. > I'd like to call it "quota-df" which means when calling statfs(2), > override/update some fields(e.g., total/used/avail of both block/inode counts） > using proper project quota information if the quota has already set to > underlying directories of overlayfs. > Do you mean project quota setting on underlying fs directories or something else? > This feature is probably useful for most of container users and there is > no serious side effect to the other parts. We can also provide a new > mount option to enable/disable the function according to different use cases. > > Although I'm still working on it but I'll post the RFC patch here for review > in recent days and hope to get some feedback from you. Any kind of suggestions > are welcomed. > I was asked about quota accounting for the merged content of overalyfs, so quota would display a number resembling du -s on the overlay mount. This means that "covered" lower files are not accounted for in the merge. Is that what you aim to achieve? If not, would that also be an interesting case for you to explore? Basically, the index directory could be used to reconstruct the entire quota information for upper and lower (and copied up) files if full indexing is enabled with nfs_export=on. > > Here are some test examples share with you (based on ext4): > > 1) project quota enabled && without hard-limit > > $ df -h /mnt/test3 /mnt/test3/df/merged > Filesystem Size Used Avail Use% Mounted on > /dev/vdb3 99G 2.5G 91G 3% /mnt/test3 > overlay 92G 201M 91G 1% /mnt/test3/df/merged > > $ df -hi /mnt/test3 /mnt/test3/df/merged > Filesystem Inodes IUsed IFree IUse% Mounted on > /dev/vdb3 6.3M 2.4K 6.3M 1% /mnt/test3 > overlay 6.3M 8 6.3M 1% /mnt/test3/df/merged > > 2) project quota enabled && with hard-limit > > $ df -h /mnt/test3 /mnt/test3/df/merged > Filesystem Size Used Avail Use% Mounted on > /dev/vdb3 99G 2.5G 91G 3% /mnt/test3 > overlay 1.0G 201M 824M 20% /mnt/test3/df/merged > > $ df -hi /mnt/test3 /mnt/test3/df/merged > Filesystem Inodes IUsed IFree IUse% Mounted on > /dev/vdb3 6.3M 2.4K 6.3M 1% /mnt/test3 > overlay 1000 8 992 1% /mnt/test3/df/merged > > I can't follow from the example below what is the expected result and why if you add the quota setup commands that could be useful. Thanks, Amir. -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
