Merge with text format branch.

Lots of changes/very little testing so far => there'll be bugs!

Use 'vgcreate -M text' to create a volume group with its metadata stored
in text files.  Text format metadata changes should be reasonably atomic,
with a (basic) automatic recovery mechanism if the system crashes while a
change is in progress.

Add a metadata section to lvm.conf to specify multiple directories if
you want (recommended) to keep multiple copies of the metadata (eg on
different filesystems).

e.g. metadata {
        dirs = ["/etc/lvm/metadata1","/usr/local/lvm/metadata2"]
}

Plenty of refinements still in the pipeline.

1 files changed, 9 insertions, 5 deletions

diff --git a/tools/vgcfgbackup.c b/tools/vgcfgbackup.c
index 93f65a179..b7419a201 100644
--- a/tools/vgcfgbackup.c
+++ b/tools/vgcfgbackup.c
@@ -12,17 +12,21 @@ static int _backup_to_file(const char *file, struct volume_group *vg)
 {
 	int r;
 	struct format_instance *tf;
+	void *context;
 
-	if (!(tf = text_format_create(vg->cmd, file, vg->cmd->um,
-				      vg->cmd->cmd_line))) {
+	if (!(context = create_text_context(vg->cmd->fmtt, file,
+					    vg->cmd->cmd_line)) ||
+	    !(tf = vg->cmd->fmtt->ops->create_instance(vg->cmd->fmtt, NULL,
+						       context))) {
 		log_error("Couldn't create backup object.");
 		return 0;
 	}
 
-	if (!(r = tf->ops->vg_write(tf, vg)))
+	if (!(r = tf->fmt->ops->vg_write(tf, vg, context)) ||
+	    !(r = tf->fmt->ops->vg_commit(tf, vg, context)))
 		stack;
 
-	tf->ops->destroy(tf);
+	tf->fmt->ops->destroy_instance(tf);
 	return r;
 }
 
@@ -31,7 +35,7 @@ static int vg_backup_single(struct cmd_context *cmd, const char *vg_name)
 	struct volume_group *vg;
 
 	log_verbose("Checking for volume group \"%s\"", vg_name);
-	if (!(vg = cmd->fid->ops->vg_read(cmd->fid, vg_name))) {
+	if (!(vg = vg_read(cmd, vg_name))) {
 		log_error("Volume group \"%s\" not found", vg_name);
 		return ECMD_FAILED;
 	}