On Mon, 2009-05-11 at 16:46 -0700, Joel Becker wrote: > On Mon, May 11, 2009 at 06:49:01PM -0400, jim owens wrote: > > Joel Becker wrote: > >> On Thu, May 07, 2009 at 10:59:04PM -0400, jim owens wrote: > >>> - fix the > >>> + if (S_ISDIR(inode->i_mode)) > >>> + return -EPERM; > >>> > >>> to be an ISREG check unless you have an argument for > >>> special files and symlinks being COWed. > >> > >> Jim, if you have a real problem this prevents, I'm all ears. > >> And if others concur that restricting it to regular files is the right > >> way to go, I can be convinced. > > > > My only problem was my past experience on non-Linux systems > > where once we said it works for multiple file types, we had > > to support that forever across all filesystems. We could add > > support for more types but not eliminate supported ones. > > Someone else pointed out that a naive user might reflink a block > device file and expect the device contents to be copied-on-write. > Obviously wrong if you understand filesystems, but let's just prevent > that misunderstanding. S_ISREG() it is. Btrfs won't be doing single directories, and I'd rather keep using a dedicated ioctl for snapshotting whole subvolumes. The semantics described here all sound sane, if this looks like the final-ish rev I'll try to find someone interested in wiring it up to the btrfs clone ioctl. It just needs a wrapper to create the new inode and copy xattrs/acls over. Thanks for doing all of this Joel. -chris -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
