process_each_pv: do full scan earlier to find new devicesdev-dct-dev-cache-full-scan

Before commit c1f246fedfc349c25749da501e68a7f70bd122b0,
_get_all_devices() did a full device scan before
get_vgnameids() was called.  New devices would be
added to the dev-cache before label scanning done
by get_vgnameids.  So, labels would be read from
new devices by the first 'pvs' command.

After that commit, _get_all_devices() was called
after get_vgnameids() was finished with label scanning.
So, new devices would be missed by the label scanning,
and would not appear to be lvm devices to the first
'pvs' command.  A new device would be added to .cache
by the first command, so the second 'pvs' command would
scan labels from it in get_vgnameids().

Now, the full device scan is factored out of
get_all_devices() and called by itself at the
start of the command so that new devices will
be known before get_vgnameids() scans labels.

1 files changed, 12 insertions, 8 deletions

diff --git a/lib/device/dev-cache.c b/lib/device/dev-cache.c
index 7626cebbd..97165dbf8 100644
--- a/lib/device/dev-cache.c
+++ b/lib/device/dev-cache.c
@@ -1026,6 +1026,16 @@ struct device *dev_cache_get_by_devt(dev_t dev, struct dev_filter *f)
 		      f->passes_filter(f, d))) ? d : NULL;
 }
 
+void dev_cache_full_scan(struct dev_filter *f)
+{
+	if (f && f->wipe) {
+		f->wipe(f); /* might call _full_scan(1) */
+		if (!full_scan_done())
+			_full_scan(1);
+	} else
+		_full_scan(1);
+}
+
 struct dev_iter *dev_iter_create(struct dev_filter *f, int dev_scan)
 {
 	struct dev_iter *di = dm_malloc(sizeof(*di));
@@ -1037,14 +1047,8 @@ struct dev_iter *dev_iter_create(struct dev_filter *f, int dev_scan)
 
 	if (dev_scan && !trust_cache()) {
 		/* Flag gets reset between each command */
-		if (!full_scan_done()) {
-			if (f && f->wipe) {
-				f->wipe(f); /* might call _full_scan(1) */
-				if (!full_scan_done())
-					_full_scan(1);
-			} else
-				_full_scan(1);
-		}
+		if (!full_scan_done())
+			dev_cache_full_scan(f);
 	} else
 		_full_scan(0);