Re: [PATCH -V5 00/24] New ACL format for better NFSv4 aclinteroperability

From: J. Bruce Fields
Date: Fri Mar 04 2011 - 19:32:37 EST


On Fri, Mar 04, 2011 at 04:08:15PM +0530, Aneesh Kumar K. V wrote:
> On Wed, 2 Mar 2011 13:58:47 -0500, "J. Bruce Fields" <bfields@xxxxxxxxxxxx> wrote:
> > On Wed, Mar 02, 2011 at 11:17:56PM +0530, Aneesh Kumar K. V wrote:
> > > On Wed, 2 Mar 2011 10:49:43 -0500, "J. Bruce Fields" <bfields@xxxxxxxxxxxx> wrote:
> > > > On Tue, Mar 01, 2011 at 12:20:36PM +0530, Aneesh Kumar K. V wrote:
> > > > > On Mon, 28 Feb 2011 16:11:45 -0500, "Ted Ts'o" <tytso@xxxxxxx> wrote:
> > > > > > Hi Aneesh,
> > > > > >
> > > > > > What is the current status of this patch series? I seem to remember
> > > > > > that Christoph and Al Viro had some objections; have those been
> > > > > > cleared yet? If not, can you summarize what their objections are?
> > > > >
> > > > > The main objection raised was the use of may_delete and may_create inode
> > > > > operations callback. They are gone now and we have MAY_* flags as
> > > > > favoured by Al Viro. The new MAY_* flags added are
> > > > >
> > > > > #define MAY_CREATE_FILE 128
> > > > > #define MAY_CREATE_DIR 256
> > > > > #define MAY_DELETE_CHILD 512
> > > > > #define MAY_DELETE_SELF 1024
> > > > > #define MAY_TAKE_OWNERSHIP 2048
> > > > > #define MAY_CHMOD 4096
> > > > > #define MAY_SET_TIMES 8192
> > > > >
> > > > >
> > > > > >
> > > > > > To be honest I haven't been paying super close attention to this patch
> > > > > > series, and I'm curious what needs to happen with it one way or
> > > > > > another.
> > > > > >
> > > > >
> > > > > IMHO we are ready to get first 11 patches upstream in the next merge
> > > > > window. ie the below set of patches.
> > > >
> > > > Why aren't all of them ready?
> > > >
> > >
> > > All except how to enable richacl in local file system is ready. I
> > > actually floated two ideas in the patch series
> > >
> > > 1) mount option
> > > 2) Ext4 compat flags.
> >
> > The choice of ACL format is a persistant property of the filesystem, not
> > of a single mount of the filesystem: for example, people can't try out
> > richacls for one mount and then decide to revert bacak to posix acls.
> >
> > (Right?) So I'm assuming we should use the latter--but I don't
> > understand what ext4 compat flags are.... Is there some disadvantage to
> > using them?
> >
>
> We already have a mount option to enable posix acl (-o acl|noacl). So
> along the same line should we have -o richacl|norichacl or should we
> have richacl as a ext4 compat flag EXT4_FEATURE_COMPAT_RICHACL. The
> compat feature can be enabled via tune2fs for an already created file
> system. Once the compat feature is enabled a -o acl mount option cause
> the richacl access check to be enabled. That can also result in
> mapping the existing posix acl in the file system to richacl and
> using mapped richacl for access restriction. With compat flag once set
> we will never be able to mount the file system again to use posix acl
> access restriction. (We cannot map richacl to posixacl because richacl
> support advanced access masks)

Sounds fine to me. I'm not sure you answered my question. Is there any
disadvantage to doing it this way?

--b.

> With mount option (-o richacl) we can still mount the file system with
> -o acl which implies we will have to ignore the richacl associated with
> files and only evaluate the posix acl stored.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/