linux-kernel - Re: [PATCH 26/29] fuse: add EXPORT_OP_STABLE

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Message-ID: <CAOQ4uxh4VaVL9PD7-_Op9Xs-z5Qrx8g6x2x5FccujQX-Cw9RqQ@mail.gmail.com>
Date: Thu, 15 Jan 2026 19:54:17 +0100
From: Amir Goldstein <amir73il@...il.com>
To: Jeff Layton <jlayton@...nel.org>
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Subject: Re: [PATCH 26/29] fuse: add EXPORT_OP_STABLE_HANDLES flag to export operations

On Thu, Jan 15, 2026 at 6:50 PM Jeff Layton <jlayton@...nel.org> wrote:
>
> Add the EXPORT_OP_STABLE_HANDLES flag to fuse export operations to indicate
> that this filesystem can be exported via NFS.
>
> Signed-off-by: Jeff Layton <jlayton@...nel.org>
> ---
>  fs/fuse/inode.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
> index 819e50d666224a6201cfc7f450e0bd37bfe32810..1652a98db639fd75e8201b681a29c68b4eab093c 100644
> --- a/fs/fuse/inode.c
> +++ b/fs/fuse/inode.c
> @@ -1208,6 +1208,7 @@ static struct dentry *fuse_get_parent(struct dentry *child)
>  /* only for fid encoding; no support for file handle */
>  static const struct export_operations fuse_export_fid_operations = {
>         .encode_fh      = fuse_encode_fh,
> +       .flags          = EXPORT_OP_STABLE_HANDLES,
>  };

These are used when the server declares FUSE_NO_EXPORT_SUPPORT
so do not opt in for NFS export.

The sad thing w.r.t FUSE is that in most likelihood server does not provide
persistent handles also when it does not declare FUSE_NO_EXPORT_SUPPORT
but we are stuck with that.

Thanks,
Amir.