On Wed, 2007-09-26 at 12:02 -0400, Jeff Moyer wrote: > Ian Kent <[EMAIL PROTECTED]> writes: > > > On Wed, 2007-09-26 at 17:32 +0200, Matthias Koenig wrote: > >> Ian Kent <[EMAIL PROTECTED]> writes: > >> > >> > On Tue, 2007-09-25 at 18:21 +0200, Matthias Koenig wrote: > >> >> Hi, > >> >> > >> >> we noticed a problem concerning loop mounts on locations that > >> >> have to be mounted before. E.g. consider the following situation, > >> >> a NFS server exporting a cd image, which we want to loop mount > >> >> locally to get access to the content: > >> >> > >> >> auto.master: > >> >> /cdimage auto.cdimage > >> >> /cdcontent auto.cdcontent > >> >> > >> >> auto.cdimage: > >> >> foo nfsserver:/cdimage/foo.img > >> >> > >> >> auto.cdcontent: > >> >> foo -fstype=auto,loop :/cdimage/foo/foo.img > >> >> > >> >> The access to /cdcontent/foo will fail, when /cdimage/foo is not > >> >> mounted before, because spawn_mount does not use SPAWN_OPT_ACCESS > >> >> in this case. > >> >> The patch below fixes this problem. > >> > > >> > I can't remember now. > >> > I wonder why I don't always call access? > >> > I must have had a reason, let me think about it for a while. > >> > >> Yes, I first tried to set SPAWN_OPT_ACCESS as default, but this did > >> not work and had the negative effect, that NFS mounts could not > >> be mounted anymore, because an access() has been done on the > >> NFS location description "nfsserver:/cdimage", which then fails. > > > > Of course, I'll go with you're patch. > > Are you sure the argument positions will be the same for all of the > mount modules? Is this really the best way to fix this?
Yes, it's possible that the "-o" could end up in a different position if the code is modified at some later time without thinking. The SPAWN_OPT_ACCESS mechanism turned out to be the only way to deal with this case. I spent a fair while trying to work out another way to do it but couldn't think of any. People had been using this method for quite a long time in personal patches. Ian _______________________________________________ autofs mailing list [email protected] http://linux.kernel.org/mailman/listinfo/autofs
