-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 27.05.2011 13:30, Stephane Chazelas wrote: > 2011-05-27 10:45:23 +0100, Hugo Mills: [...] >>> How could a "subvolume 285" become a "top level"? >> >>> How does one get a subvolume with a top-level other than "5"? >> >> This just means that subvolume 287 was created (somewhere) >> inside subvolume 285. >> >> Due to the way that the FS trees and subvolumes work, there's no >> global namespace structure in btrfs; that is, there's no single >> data structure that represents the entirety of the file/directory >> hierarchy in the filesystem. Instead, it's broken up into these >> sub-namespaces called subvolumes, and we only record parent/child >> relationships for each subvolume separately. The "full path" you >> get from "btrfs subv list" is reconstructed from that information >> in userspace(*). > [...] > > Thanks, I can understand that. What I don't get is how one creates > a subvol with a top-level other than 5. I might be missing the > obvious, though. > > If I do: > > btrfs sub create A btrfs sub create A/B btrfs sub snap A A/B/C > > A, A/B, A/B/C have their top-level being 5. How would I get a new > snapshot to be a child of A/B for instance? > > In my case, 285, was not appearing in the btrfs sub list output, > 287 was a child of 285 with path "data" while all I did was create > a snapshot of 284 (path u6:10022/vm+xfs@u8/xvda1/g8/v3/data in vol > 5) in u6:10022/vm+xfs@u8/xvda1/g8/v3/snapshots/2011-03-30 > > So I did manage to get a volume with a parent other than 5, but I > did not ask for it. Reconsidering the explanations on btrfs subvolume list in this thread I get the impression that a line in the output of btrfs subvolume list with top level other than 5 indicates that the backrefs from one subvolume to its parent are broken.
What's your opinion on this? Thanks, Andreas -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJN34/fAAoJEJIcBJ3+XkgiTVcP/iQ62XnEAS0rVGOl+0DNqySb 5A5N3/pzhgzOdMhldJYtgg0K60lV0qs0H31ITgOdGUtpEXibybU/6Yuy2yIfqx0T 3OQCb2KE8la2hlh472aTuIN3beljFYzPu89KVrGaT6kD7lABRXkCG5y1Y5+fvVXI gtq5/mCqvyaxxUMTppgzLHwtt0YVICZeCDmALMtsVe1DMr0uT5QI0XY+4Glpl7AJ 1G6Plyr7qciOwdRgvM/7NkHl/gsJ4GEvIOSVFiBM4Hb8fX7APy/C//sIPfD2Kg5K 7B6sJMpS2i87uEsrr+w8j7nLWn9Y/255W89r/cG3uISDFRn/RDs9xEnRCfEXb6qf ZeBPVfv9+pN6mmwrfUOJr4pb44f9/UgTC+udCfzKm1yWVci895NIGsfJgYfA0OOf GRnCWVRwFStiUGf0uSRH0yJAW5ozI8DzDnDKzByFpMcmw3eVNq5usCftA4XxVi7r Wu/v9z6DNdHj7ibsSdeYXAmVGpwennILPeEvGWDbMB/OZIDKC3s75yCzXIhxWpya zR5jGDbGj9IkvUhSAwW0afFqBK+bZny/SJsqA0vFH7Emao0CG1FIJVlN7/S6OSg1 Dtye//ocjhO0kf3OX3hj689n4/mvaBZeVArCz5vJzG2wEcRZTF4DZ4ApsUjne0LC q4L2n9nLM4yeAs+YjFx/ =R53y -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
