[Gluster-devel] Lazy umount emulation

[Emmanuel Dreyfus]

Hi

Lazy umount is a Linux-only feature that let userland tell the kernel to
umount a filesystem as soon as it drops the last reference to it. It is
used at a few places by GlusterFS and is a portability problem.
brick-replace will not currently work without it, which is a critical
problem.

I wrote a basic lazy umount emulation: it spawn a thread that will try
periodically try to umount. Could someone review?
http://review.gluster.com/8649

For now the prototype is 
int gf_umount_lazy (char *xlname, char *path);

The thing could be factorized further: if this is considered useful, I
can do a umount wrapper with a flag argument which value could be
GF_MNT_LAZY, GF_MNT_FORCE. I can also add a timeout to the periodical
lazy umount attemps. Please comment.

-- 
Emmanuel Dreyfus
http://hcpnet.free.fr/pubz
manu at netbsd.org