From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D29661E47BA; Wed, 9 Jul 2025 03:59:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752033553; cv=none; b=kFi7TIjA8Iwp76o+owiNIxuOxCv0h9OLJI0rXRZIK1vY0xcwD79j5pnHQxxyJe2XQ9AjD+qoZwlN0SIvDrjkBY2HHi7qu4EYYZXWMlgd7qMajsvsW+lGrMZWZXFqBdTIpNsl/UJ+heMPIsMuS3DbXUSQ8fIy48dMiS1PiEkD+Sk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752033553; c=relaxed/simple; bh=QytHeqnrZC2ddp9eJpzCiJaHZYXcVEL3Y7kDVMmL3JU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hNynulNp1nVqZ7n6WgRN09PuQ0gAgvUc0faVYlAOdJ3XUu9DriFDIofuEIkRVDoBecM9PApTn3bvxmHyrGzMs7x9rbiV+l8hrZl1zwO5L5nYRsurFnUekMIgWeTUax9N2KkmHjXOjln3M9md5GlRJCqVheZMgD3cFAeGB5JUyqQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=G+F+jf7e; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="G+F+jf7e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4CF41C4CEF0; Wed, 9 Jul 2025 03:59:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752033552; bh=QytHeqnrZC2ddp9eJpzCiJaHZYXcVEL3Y7kDVMmL3JU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=G+F+jf7eTJoZeBlRdUxYZgi+fL8+T8t834jF3yNHRTd+OhJ9Yhg1I7wAX/yFH/YAZ uGEqYwpAHDcuvT+QqSM7ZjOLnKbKQv1VPVw/lENIbTX+RcNEmUeUpQtR/QqLpWIBkO TCXgKk7DaR2RRSE0oL7eS1SwgASxr1S1j08W1YF80X/zYAUFmgn3UgXqZGeIX5q1YL jYrTN3fmIhWhOQpxCRHTZnUNNz6Xx1i1GF7WgnqLk4XJF43bWhzKXS3hwm41CkT85S xHCbc8zmhN76MMR7xG6O2puO8kSf+UDTdAFeeU8qtxqcyXxa1unEsk/ZLQSE2+vRGI 59myGqc7C424Q== Date: Tue, 8 Jul 2025 20:59:11 -0700 From: "Darrick J. Wong" To: John Groves Cc: Dan Williams , Miklos Szeredi , Bernd Schubert , John Groves , Jonathan Corbet , Vishal Verma , Dave Jiang , Matthew Wilcox , Jan Kara , Alexander Viro , Christian Brauner , Randy Dunlap , Jeff Layton , Kent Overstreet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, linux-fsdevel@vger.kernel.org, Amir Goldstein , Jonathan Cameron , Stefan Hajnoczi , Joanne Koong , Josef Bacik , Aravind Ramesh , Ajay Joshi Subject: Re: [RFC V2 11/18] famfs_fuse: Basic famfs mount opts Message-ID: <20250709035911.GE2672029@frogsfrogsfrogs> References: <20250703185032.46568-1-john@groves.net> <20250703185032.46568-12-john@groves.net> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250703185032.46568-12-john@groves.net> On Thu, Jul 03, 2025 at 01:50:25PM -0500, John Groves wrote: > * -o shadow= What is a shadow? > * -o daxdev= And, uh, if there's a FUSE_GET_DAXDEV command, then what does this mount option do? Pre-populate the first element of that set? --D > Signed-off-by: John Groves > --- > fs/fuse/fuse_i.h | 8 +++++++- > fs/fuse/inode.c | 28 +++++++++++++++++++++++++++- > 2 files changed, 34 insertions(+), 2 deletions(-) > > diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h > index a592c1002861..f4ee61046578 100644 > --- a/fs/fuse/fuse_i.h > +++ b/fs/fuse/fuse_i.h > @@ -583,9 +583,11 @@ struct fuse_fs_context { > unsigned int blksize; > const char *subtype; > > - /* DAX device, may be NULL */ > + /* DAX device for virtiofs, may be NULL */ > struct dax_device *dax_dev; > > + const char *shadow; /* famfs - null if not famfs */ > + > /* fuse_dev pointer to fill in, should contain NULL on entry */ > void **fudptr; > }; > @@ -941,6 +943,10 @@ struct fuse_conn { > /** uring connection information*/ > struct fuse_ring *ring; > #endif > + > +#if IS_ENABLED(CONFIG_FUSE_FAMFS_DAX) > + char *shadow; > +#endif > }; > > /* > diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c > index e48e11c3f9f3..a7e1cf8257b0 100644 > --- a/fs/fuse/inode.c > +++ b/fs/fuse/inode.c > @@ -766,6 +766,9 @@ enum { > OPT_ALLOW_OTHER, > OPT_MAX_READ, > OPT_BLKSIZE, > +#if IS_ENABLED(CONFIG_FUSE_FAMFS_DAX) > + OPT_SHADOW, > +#endif > OPT_ERR > }; > > @@ -780,6 +783,9 @@ static const struct fs_parameter_spec fuse_fs_parameters[] = { > fsparam_u32 ("max_read", OPT_MAX_READ), > fsparam_u32 ("blksize", OPT_BLKSIZE), > fsparam_string ("subtype", OPT_SUBTYPE), > +#if IS_ENABLED(CONFIG_FUSE_FAMFS_DAX) > + fsparam_string("shadow", OPT_SHADOW), > +#endif > {} > }; > > @@ -875,6 +881,15 @@ static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param) > ctx->blksize = result.uint_32; > break; > > +#if IS_ENABLED(CONFIG_FUSE_FAMFS_DAX) > + case OPT_SHADOW: > + if (ctx->shadow) > + return invalfc(fsc, "Multiple shadows specified"); > + ctx->shadow = param->string; > + param->string = NULL; > + break; > +#endif > + > default: > return -EINVAL; > } > @@ -888,6 +903,7 @@ static void fuse_free_fsc(struct fs_context *fsc) > > if (ctx) { > kfree(ctx->subtype); > + kfree(ctx->shadow); > kfree(ctx); > } > } > @@ -919,7 +935,10 @@ static int fuse_show_options(struct seq_file *m, struct dentry *root) > else if (fc->dax_mode == FUSE_DAX_INODE_USER) > seq_puts(m, ",dax=inode"); > #endif > - > +#if IS_ENABLED(CONFIG_FUSE_FAMFS_DAX) > + if (fc->shadow) > + seq_printf(m, ",shadow=%s", fc->shadow); > +#endif > return 0; > } > > @@ -1017,6 +1036,9 @@ void fuse_conn_put(struct fuse_conn *fc) > } > if (IS_ENABLED(CONFIG_FUSE_PASSTHROUGH)) > fuse_backing_files_free(fc); > +#if IS_ENABLED(CONFIG_FUSE_FAMFS_DAX) > + kfree(fc->shadow); > +#endif > call_rcu(&fc->rcu, delayed_release); > } > } > @@ -1834,6 +1856,10 @@ int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) > sb->s_root = root_dentry; > if (ctx->fudptr) > *ctx->fudptr = fud; > + > +#if IS_ENABLED(CONFIG_FUSE_FAMFS_DAX) > + fc->shadow = kstrdup(ctx->shadow, GFP_KERNEL); > +#endif > mutex_unlock(&fuse_mutex); > return 0; > > -- > 2.49.0 > >