>
> On Thu, 2008-08-07 at 17:15 -0500, Serge E. Hallyn wrote:
> > Quoting Andrew Morton (
akpm@linux-foundation.org):
> > > On Thu, 07 Aug 2008 19:40:14 +0800
> > > Ian Kent <raven@themaw.net> wrote:
> > >
> > > > Patch to track the uid and gid of the last process to request a mount
> > > > for on an autofs dentry.
> > >
> > > pet peeve: changelog should not tell the reader that this is a "patch".
> > > Because when someone is reading the changelog in the git repository,
> > > they hopefully already know that.
> > >
> > > > Signed-off-by: Ian Kent <raven@themaw.net>
> > > >
> > > > ---
> > > >
> > > > fs/autofs4/autofs_i.h | 3 +++
> > > > fs/autofs4/inode.c | 2 ++
> > > > fs/autofs4/waitq.c | 34 ++++++++++++++++++++++++++++++++++
> > > > 3 files changed, 39 insertions(+), 0 deletions(-)
> > > >
> > > >
> > > > diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
> > > > index ea024d8..fa76d18 100644
> > > > --- a/fs/autofs4/autofs_i.h
> > > > +++ b/fs/autofs4/autofs_i.h
> > > > @@ -63,6 +63,9 @@ struct autofs_info {
> > > > unsigned long last_used;
> > > > atomic_t count;
> > > >
> > > > + uid_t uid;
> > > > + gid_t gid;
> > > > +
> > > > mode_t mode;
> > > > size_t size;
> > > >
> > > > diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
> > > > index 9ca2d07..9408507 100644
> > > > --- a/fs/autofs4/inode.c
> > > > +++ b/fs/autofs4/inode.c
> > > > @@ -53,6 +53,8 @@ struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
> > > > atomic_set(&ino->count, 0);
> > > > }
> > > >
> > > > + ino->uid = 0;
> > > > + ino->gid = 0;
> > > > ino->mode = mode;
> > > > ino->last_used = jiffies;
> > > >
> > > > diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
> > > > index 6d87bb1..7c60c0b 100644
> > > > --- a/fs/autofs4/waitq.c
> > > > +++ b/fs/autofs4/waitq.c
> > > > @@ -457,6 +457,40 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,
> > > >
> > > > status = wq->status;
> > > >
> > > > + /*
> > > > + * For direct and offset mounts we need to track the requestrer
> > >
> > > typo which I'll fix.
> > >
> > > > + * uid and gid in the dentry info struct. This is so it can be
> > > > + * supplied, on request, by the misc device ioctl interface.
> > > > + * This is needed during daemon resatart when reconnecting
> > > > + * to existing, active, autofs mounts. The uid and gid (and
> > > > + * related string values) may be used for macro substitution
> > > > + * in autofs mount maps.
> >
> > Hi Ian,
> >
> > could you say just a few more words on these macro substitution?
> >
> > I think your use of uids can completely ignore user namespaces, but it
> > depends on who does the macro substitutions and how...
>
> Suppose we have an autofs map entry in /etc/auto.master:
> /test /etc/auto.test
>
> and in /etc/auto.test
>
> im1 /om1 server:/dir1 \
> /om2/$USER server2:/dir2
>
> Then if this is automounted and the daemon is sent a SIGKILL and started
> again we need the uid number that was used when this was mounted to
> re-construct the offsets (/om2/$USER in this case needs the
> substitution). The uid is used to lookup the user name.
