You can do this with a stackable FSAL, since it's on top, not
underneath, so it can override anything you want. You can even just put
the symlink part in your FSAL, and defer everything else so VFS, if you
want.
Daniel
On 11/08/2017 03:04 PM, Frank Filz wrote:
Yea, in the case of wanting to allow symlink exports, you would need to
replace the method. I’d be interested in why you want to allow them.
That is something that actually could be handled by a config or compile
option.
Frank
*From:*sriram patil [mailto:spsrirampa...@gmail.com]
*Sent:* Wednesday, November 8, 2017 10:20 AM
*To:* Frank Filz <ffilz...@mindspring.com>
*Cc:* d...@redhat.com; nfs-ganesha-devel@lists.sourceforge.net
*Subject:* Re: [Nfs-ganesha-devel] Subfsal export
Hi,
In case of stackable FSALs, what if I want the underlying FSAL behave
differently. For example, VFS does not allow symlink exports,
lookup_path fails if we try to export symlink pointing to a directory.
There can be such cases where I want to defer (very small changes) from
the underlying "sub fsal". For bypassing some part of the underlying
fsal function, is rewriting the function the only way?
Thanks,
Sriram
On Wed, Nov 8, 2017 at 11:22 PM, sriram patil <spsrirampa...@gmail.com
<mailto:spsrirampa...@gmail.com>> wrote:
Hmm stackable FSAL sounds like a good option. Let me investigate on
that. I was mainly going with sub fsal because of xfs.
I agree with both of you about pushing FSAL changes to upstream. Let
me see if I can make that happen.
Thanks,
Sriram
On 08-Nov-2017 11:03 PM, "Frank Filz" <ffilz...@mindspring.com
<mailto:ffilz...@mindspring.com>> wrote:
> You might want to consider a stackable FSAL instead.
FSAL_NULL is a good
> example to start from. It's much more flexible than
sub_fsals for VFS.
If I
> was implementing PanFS now, I'd use a stackable FSAL instead.
Yea, this is a good point. Probably even the XFS/VFS split
should be done
with stackable FSAL.
> Ganesha is LGPL specifically to allow non-FOSS FSALs.
However, if the
FSAL
> itself does not require proprietary code, there are many
advantages to
open
> sourcing it and getting it upstream. Not the least is that
changes to
APIs and
> the build system will be fixed by the community, so there
will be fewer
cases
> of sudden breakage for you to fix.
On top of direct API impacts, it also helps to understand how
other FSALs
are using Ganesha so that not only do we not break the API, but
don't break
other assumptions that were made. It also is a better platform for
requesting FSAL specific API accommodation (for a recent
example, see
compute_readdir_cookie and whence_is_name support that was added for
FSAL_RGW, though added in a generic way so other FSALs might use
it).
Frank
> Daniel
>
> On 11/08/2017 10:51 AM, sriram patil wrote:
> > Yes, I am making a new sub fsal. May not push it to
upstream because
> > it will not be useful without the whole framework/product.
As part of
> > that, I wanted to allocate an export object which has some
extra
> > fields, other than the ones in vfs_fsal_export.
> >
> > Also, I hope creating a sub fsal and not making the
implementation
> > opensource does not violate any license terms.
> >
> > Thanks,
> > Sriram
> >
> > On 08-Nov-2017 8:19 PM, "Daniel Gryniewicz"
<d...@redhat.com <mailto:d...@redhat.com>
> > <mailto:d...@redhat.com <mailto:d...@redhat.com>>> wrote:
> >
> > On 11/08/2017 02:41 AM, sriram patil wrote:
> >
> > Hi,
> >
> > In the subfsal framework, I see that subfsals can
have their own
> > fsal_obj_handles by implementing
vfs_sub_alloc_handle and then
> > use subfsal specific variables using container_of.
> >
> > It does not provide same functionality for
fsal_export however.
> > There is no vfs_sub_alloc_export.
vfs_create_export just calls
> > gsh_calloc to allocate vfs_fsal_export, giving no
flexibility.
> >
> > PANFS has its own struct panfs_fsal_export but it
is not
> > allocated anywhere. It still uses container_of on
> > vfs_fsal_export. This looks like a memory
corruption. The last
> > commit in PANFS however is about a year back, not
sure if it is
> > actively developed.
> >
> >
> > PANFS is unused and unmaintained. We keep it building,
but that's
it.
> >
> > Considering the above scenario, it makes sense to have
> > vfs_sub_alloc_export to allow allocating the
wrapper export
> > object. Any thoughts?
> >
> >
> > This seems like it was a bug in the original
implementation for
> > PanFS. It probably should be fixed, but the VFS
sub_fsal doesn't
> > need it, so it works for now.
> >
> > Are you making a new sub_fsal?
> >
> > Daniel
> >
> >
----------------------------------------------------------------------------
--
> > Check out the vibrant tech community on one of the
world's most
> > engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> > _______________________________________________
> > Nfs-ganesha-devel mailing list
> > Nfs-ganesha-devel@lists.sourceforge.net
<mailto:Nfs-ganesha-devel@lists.sourceforge.net>
> > <mailto:Nfs-ganesha-devel@lists.sourceforge.net
<mailto:Nfs-ganesha-devel@lists.sourceforge.net>>
> > https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel
> >
<https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel>
> >
>
>
>
----------------------------------------------------------------------------
--
> Check out the vibrant tech community on one of the world's
most engaging
> tech sites, Slashdot.org! http://sdm.link/slashdot
> _______________________________________________
> Nfs-ganesha-devel mailing list
> Nfs-ganesha-devel@lists.sourceforge.net
<mailto:Nfs-ganesha-devel@lists.sourceforge.net>
> https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient&utm_term=icon>
Virus-free. www.avast.com
<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient&utm_term=link>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Nfs-ganesha-devel mailing list
Nfs-ganesha-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel
