On Wed, 2016-09-21 at 16:14 +0200, Miklos Szeredi wrote: > On Wed, Sep 21, 2016 at 2:25 PM, Jean-Pierre André > <jean-pierre.andre@xxxxxxxxxx> wrote: > > > > > The code for Posix ACLs support within the kernel is > > already present in ntfs-3g (just have to define the > > macro KERNELACLS in order to disable the checks > > within ntfs-3g and rely on the kernel ones). > > > > This however relies on assumptions I made a few years > > back, and might be invalid now. I will at least have > > to set some flag in the init callback. > > > > The ACLs are supposed to be set and retrieved through > > the extended attributes system.posix_acl_access and > > system.posix_acl_default. Recent posts about it in > > this list mention "xattr handlers", do they mean > > getxattr() and setxattr() on these extended attributes ? > Right. > > > > > Also the sync with the file mode is done natively, > > as the ACLs and modes are translated to a single > > object (an NTFS ACL). There is no need for fuse to > > duplicate the mode to a ACL setting or conversely. > > > > Now the main problem for ntfs-3g is to migrate to > > libfuse3, still keeping the compatibility with non-Linux > > implementations (MacOSX, OpenIndiana, and others). > > I have not done anything about it yet. > > > > Does the Posix ACL in-kernel support require libfuse3 ? > Not really, the most important change (and apparently the only one > that ntfs-3g cares about) will be the added capability flag, but it's > trivial to add it to libfuse2. > > Thanks, > Miklos Hi, I'm currently trying to port my code to take advantage of this. I've found myself in sort of a catch-22 situation: I don't know whether to pass default_permissions or not. Right now, I support ACLs by not using default_permissions. However, the FUSE_POSIX_ACL capability is only given when default_permissions is turned on. If I unconditionally set FUSE_POSIX_ACL in the "want" flags, the capability remains disabled if default_permissions is off. I need to support ACLs on backlevel platforms with default_permissions off, and the coming platforms with default_permissions on. How do you suggest I determine whether to provide it or not? Regards, Michael Theall -- 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
