fstat(1) from FreeBSD 6.2 can not display information about files which reside in a unionfs, as can be seen in this example:
USER CMD PID FD MOUNT INUM MODE SZ|DV R/W pi less 31028 root - - ?(unionfs) - pi less 31028 wd - - ?(unionfs) - pi less 31028 jail - - ?(unionfs) - pi less 31028 text - - ?(unionfs) - pi less 31028 0 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 rw pi less 31028 1 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 rw pi less 31028 2 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 rw pi less 31028 3 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 r pi less 31028 4 - - ?(unionfs) -This patch fixes it, as can be seen in this other example:
USER CMD PID FD MOUNT INUM MODE SZ|DV R/W pi less 31028 root /vserv/vserv3.nepustil.net 4804764 drwxrwxr-x 512 r unionupper /usr pi less 31028 wd /vserv/vserv3.nepustil.net 5042109 drwx------ 1536 r unionupper /usr pi less 31028 jail /vserv/vserv3.nepustil.net 4804764 drwxrwxr-x 512 r unionupper /usr pi less 31028 text /vserv/vserv3.nepustil.net 5159119 -r-xr-xr-x 109300 r unionlower /usr pi less 31028 0 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 rw pi less 31028 1 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 rw pi less 31028 2 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 rw pi less 31028 3 /vserv/vserv3.nepustil.net/dev 109 crw--w---- ttyp5 r pi less 31028 4 /vserv/vserv3.nepustil.net 5042526 -rw------- 702 r unionupper /usrThe filesytems involved:
f6# df [...] Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/ad0s1e 43938150 20634736 19788362 51% /usr [...] <below>:/vserv/template/stage2 87876300 64572886 19788362 77% /vserv/vserv3.nepustil.net devfs 1 1 0 100% /vserv/vserv3.nepustil.net/dev [...]were mounted with the following command:
/sbin/mount -t unionfs -o noatime,below,copymode=transparent /vserv/template/stage2 /vserv/vserv3.nepustil.net /sbin/mount_devfs devfs /vserv/vserv3.nepustil.net
How to apply:
cd /tmp/
fetch http://opsec.eu/src/fstat-unionfs-patch/patch-20070812
cd /usr
patch < /tmp/patch-20070812
cd /usr/src/usr.bin/fstat/
make install
TODO: support other filesystems besides UFS as lower filesystems