On Wed, Jan 21, 2015 at 03:05:25PM +0800, Ian Kent wrote: > On Fri, 2015-01-16 at 10:25 -0500, J. Bruce Fields wrote: > > On Fri, Jan 16, 2015 at 09:01:13AM +0800, Ian Kent wrote: > > > On Thu, 2015-01-15 at 11:27 -0500, J. Bruce Fields wrote: > > > > On Thu, Jan 15, 2015 at 08:26:12AM +0800, Ian Kent wrote: > > > > > On Wed, 2015-01-14 at 17:10 -0500, J. Bruce Fields wrote: > > > > > > > On Wed, Jan 14, 2015 at 05:32:22PM +0800, Ian Kent wrote: > > > > > > > > There are other difficulties to tackle as well, such as how to > > > > > > > > decide > > > > > > > > if contained helper execution is needed. For example, if a > > > > > > > > mount has > > > > > > > > been propagated to a container or bound into the container tree > > > > > > > > (such > > > > > > > > as with the --volume option of "docker run") the root init > > > > > > > > namespace > > > > > > > > may need to be used and not the container namespace. > > > > > > > > > > > > I think you have to go through each of the existing upcall examples > > > > > > and > > > > > > decide what's needed for each. > > > > > > > > > > > > At least for the nfsv4 idmapper I would've thought the namespace the > > > > > > mount was done in would be the right choice, hence my previous > > > > > > question. > > > > > > > > > > Probably but you don't necessarily know what namespace the mount was > > > > > done in. It may have been propagated from another namespace or > > > > > (although > > > > > I don't think it works yet) bound from another container using the > > > > > volumes-from docker option. > > > > > > > > Name-id mappings should be associated with the superblock, I guess--so > > > > don't you store a pointer to the right thing there? > > > > > > Quite possibly but my original point was, without an acceptable > > > mechanism to execute the helper we can't know what might need to be done > > > to use it. > > > > At least for me it would be easier to review if it came with at least > > one example user. > > Haven't seen any negative responses but perhaps people are still away > over Xmas. > > In the mean time it's probably a good idea to add some use cases to the > series in case the approach is OK. > > I'll have a look at the nfsd code and see if I can spot the places.
On the nfsd side it's just the one call_usermodehelper in fs/nfsd/nfs4recover.c. The tricky part is figuring out where the namespace information should come from. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
