meta: (re-)Implement Meta translator

The meta translator exposes details about glusterfs itself
in the form of a virtual namespace.

Loading the translator on the client side creates the
meta virtual view under $mntpoint/.meta by default. The
directory is not listed (even with ls -a) and can be
accessed by doing a "cd /mnt/.meta"

Change-Id: I5ffdf39203841a9562a8280a1f79dc76d4dded5d
BUG: 1089216
Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-on: http://review.gluster.org/7509
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Harshavardhana <harsha@harshavardhana.net>

1 files changed, 72 insertions, 0 deletions

diff --git a/xlators/meta/src/plugins/xlator-dir.c b/xlators/meta/src/plugins/xlator-dir.c
new file mode 100644
index 00000000000..279df385cef
--- /dev/null
+++ b/xlators/meta/src/plugins/xlator-dir.c
@@ -0,0 +1,72 @@
+/*
+   Copyright (c) 2014 Red Hat, Inc. <http://www.redhat.com>
+   This file is part of GlusterFS.
+
+   This file is licensed to you under your choice of the GNU Lesser
+   General Public License, version 3 or any later version (LGPLv3 or
+   later), or the GNU General Public License, version 2 (GPLv2), in all
+   cases as published by the Free Software Foundation.
+*/
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "xlator.h"
+#include "defaults.h"
+
+#include "meta-mem-types.h"
+#include "meta.h"
+#include "meta-hooks.h"
+
+
+static struct meta_dirent xlator_dir_dirents[] = {
+	DOT_DOTDOT,
+
+	{ .name = "view",
+	  .type = IA_IFDIR,
+	  .hook = meta_view_dir_hook,
+	},
+	{ .name = "type",
+	  .type = IA_IFREG,
+	  .hook = meta_type_file_hook,
+	},
+	{ .name = "name",
+	  .type = IA_IFREG,
+	  .hook = meta_name_file_hook,
+	},
+	{ .name = "subvolumes",
+	  .type = IA_IFDIR,
+	  .hook = meta_subvolumes_dir_hook,
+	},
+	{ .name = "options",
+	  .type = IA_IFDIR,
+	  .hook = meta_options_dir_hook,
+	},
+	{ .name = NULL }
+};
+
+
+static struct meta_ops xlator_dir_ops = {
+	.fixed_dirents = xlator_dir_dirents
+};
+
+
+int
+meta_xlator_dir_hook (call_frame_t *frame, xlator_t *this, loc_t *loc,
+		      dict_t *xdata)
+{
+	glusterfs_graph_t *graph = NULL;
+	xlator_t *xl = NULL;
+
+	graph = meta_ctx_get (loc->parent, this);
+
+	xl = xlator_search_by_name (graph->first, loc->name);
+
+	meta_ctx_set (loc->inode, this, xl);
+
+	meta_ops_set (loc->inode, this, &xlator_dir_ops);
+
+	return 0;
+}