Re: [PATCH] xfs_io/lsattr: expose FS_XFLAG_HASATTR flag

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Wed, Nov 06, 2019 at 12:45:55PM -0600, Eric Sandeen wrote:
> On 11/6/19 12:29 PM, Amir Goldstein wrote:
> > On Wed, Nov 6, 2019 at 6:03 PM Darrick J. Wong <darrick.wong@oracle.com> wrote:
> >>
> >> On Wed, Nov 06, 2019 at 07:58:55AM +0200, Amir Goldstein wrote:
> >>> For efficient check if file has xattrs.
> >>>
> >>> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
> >>> ---
> >>>  io/attr.c | 2 ++
> >>>  1 file changed, 2 insertions(+)
> >>>
> >>> diff --git a/io/attr.c b/io/attr.c
> >>> index b713d017..ba88ef16 100644
> >>> --- a/io/attr.c
> >>> +++ b/io/attr.c
> >>> @@ -37,6 +37,7 @@ static struct xflags {
> >>>       { FS_XFLAG_FILESTREAM,          "S", "filestream"       },
> >>>       { FS_XFLAG_DAX,                 "x", "dax"              },
> >>>       { FS_XFLAG_COWEXTSIZE,          "C", "cowextsize"       },
> >>> +     { FS_XFLAG_HASATTR,             "X", "has-xattr"        },
> >>>       { 0, NULL, NULL }
> >>>  };
> >>>  #define CHATTR_XFLAG_LIST    "r"/*p*/"iasAdtPneEfSxC"
> >>
> >> /me wonders if this should have /*X*/ commented out the same way we do
> >> for "p".
> > 
> > Sure. Eric, please let me know if you want a re-submit for this.
> 
> Ummm I'll just stage it now and add it so I don't forget
> 
> like:
> 
> #define CHATTR_XFLAG_LIST    "r"/*p*/"iasAdtPneEfS"/*X*/"xC"
> 
> that, right?

Right.

--D

> >>
> >> Otherwise, the patch looks ok to me...
> >>
> >> /me *also* wonders how many filesystems fail to implement this flag but
> >> support xattrs.
> >>
> >> Oh.  All of them.  Though I assume overlayfs is being patched... :)
> >>
> > 
> > It doesn't need to be patched. It doesn't have xattr storage of its own.
> > The ioctl is passed down to the underlying fs (*).
> > (*) The ioctl is currently blocked on overlayfs directories.
> > 
> > Thanks,
> > Amir.
> >