device_id: accept wwids containing QEMU HARDDISK

A wwid may be useful even when it contains the string
"QEMU HARDDISK", so allow these to be used.

lib/device/device_id.c

@@ -629,19 +629,11 @@ const char *device_id_system_read(struct cmd_context *cmd, struct device *dev, u
 	struct dev_wwid *dw;
 	unsigned i;
 
-	if (idtype == DEV_ID_TYPE_SYS_WWID) {
+	if (idtype == DEV_ID_TYPE_SYS_WWID)
 		dev_read_sys_wwid(cmd, dev, sysbuf, sizeof(sysbuf), NULL);
 
-		/* FIXME: enable these QEMU t10 wwids */
+	else if (idtype == DEV_ID_TYPE_SYS_SERIAL)
-
-		/* qemu wwid begins "t10.ATA     QEMU HARDDISK ..." */
-		if (strstr(sysbuf, "QEMU HARDDISK"))
-			sysbuf[0] = '\0';
-	}
-
-	else if (idtype == DEV_ID_TYPE_SYS_SERIAL) {
 		_dev_read_sys_serial(cmd, dev, sysbuf, sizeof(sysbuf));
-	}
 
 	else if (idtype == DEV_ID_TYPE_MPATH_UUID) {
 		read_sys_block(cmd, dev, "dm/uuid", sysbuf, sizeof(sysbuf));
@@ -833,6 +825,22 @@ static int _dev_has_stable_id(struct cmd_context *cmd, struct device *dev)
 	 * system_read.)
 	 */
 	dm_list_iterate_items(id, &dev->ids) {
+		/*
+		 * An unfortunate special case to work around a previous lvm version
+		 * where wwid's containing "QEMU HARDDISK" were ignored, which would
+		 * generally cause the device to have IDTYPE=devname.  On reboot,
+		 * when the dev name changes, the search for a new device may use
+		 * the search_for_devnames="auto" setting which uses this function
+		 * to decide if a dev should be checked as the renamed device or not.
+		 * It's not if it has a wwid, since the renamed dev we're looking for
+		 * would be using sys_wwid if it had a wwid.  Now that QEMU wwids
+		 * are used, we still have to check devs with a QEMU wwid to see if
+		 * it's the renamed dev.
+		 */
+		if (((id->idtype == DEV_ID_TYPE_SYS_WWID) || (id->idtype == DEV_ID_TYPE_WWID_T10)) &&
+		     id->idname && strstr(id->idname, "QEMU"))
+			continue;
+
 		if ((id->idtype != DEV_ID_TYPE_DEVNAME) && id->idname)
 			return 1;
 	}
@@ -843,9 +851,14 @@ static int _dev_has_stable_id(struct cmd_context *cmd, struct device *dev)
 	 */
 
 	if ((idname = device_id_system_read(cmd, dev, DEV_ID_TYPE_SYS_WWID))) {
+		/* see comment above */
+		if (!strstr(idname, "QEMU")) {
 			free((void*)idname);
 			return 1;
 		}
+		free((void*)idname);
+		return 0;
+	}
 
 	if ((idname = device_id_system_read(cmd, dev, DEV_ID_TYPE_SYS_SERIAL))) {
 		free((void*)idname);

test/shell/devicesfile-vpd-ids.sh

@@ -16,6 +16,10 @@ SKIP_WITH_LVMPOLLD=1
 
 . lib/inittest
 
+aux lvmconf 'devices/global_filter = [ "a|.*|" ]' \
+            'devices/filter = [ "a|.*|" ]'
+
+
 SYS_DIR="sys"
 # requires trailing / to match dm
 aux lvmconf "devices/device_id_sysfs_dir = \"$PWD/$SYS_DIR/\"" \
@@ -499,6 +503,75 @@ grep "IDTYPE=devname" "$DF" | tee out
 grep "IDNAME=$DEV1" out
 cleanup_sysfs
 
+#
+# Test wwid containing "QEMU HARDDISK".
+# These wwids were once ignored.  When the qemu wwid
+# was ignored, the dev would likely have used IDTYPE=devname.
+# When that dev is renamed on reboot, it needs to be found
+# on the device with the qemu wwid.
+# The original logic behind search_for_devnames="auto" would
+# have ignored any device with a wwid when searching for the
+# renamed device (since devs with wwids would not use the
+# devname idtype.)  However, in this case, a device with the
+# qemu wwid does use the devname idtype and needs to be checked,
+# so it's a special case in the code to look at devs with
+# any qemu wwid.
+#
+aux lvmconf "devices/search_for_devnames = \"auto\""
+
+rm "$DF"
+aux wipefs_a "$DEV1"
+touch "$DF"
+pvcreate "$DEV1"
+vgcreate $vg1 "$DEV1"
+cat "$DF"
+grep "IDTYPE=devname" "$DF" | tee out
+grep "IDNAME=$DEV1" out
+mkdir -p "$SYS_DIR/dev/block/$MAJOR1:$MINOR1/device"
+echo -n "0QEMU QEMU  HARDDISK  1" > "$SYS_DIR/dev/block/$MAJOR1:$MINOR1/device/wwid"
+pvs -o+uuid,deviceidtype,deviceid "$DEV1"
+# Rename device, simulating reboot
+sed -e "s|IDNAME=$DEV1|IDNAME=/dev/sdx|" "$DF" > tmpdf
+sed -e "s|DEVNAME=$DEV1|DEVNAME=/dev/sdx|" tmpdf > "$DF"
+cat "$DF"
+# pvs will find PV on DEV1 and fix IDNAME
+pvs -o+uuid,deviceidtype,deviceid | tee out
+grep "$DEV1" out
+grep "IDTYPE=devname" "$DF" | tee out
+grep "IDNAME=$DEV1" out
+rm "$SYS_DIR/dev/block/$MAJOR1:$MINOR1/device/wwid"
+cleanup_sysfs
+
+# set search_for_devnames="auto"
+# set wwid with QEMU HARDDISK for the disk
+# add disk to system.devices, should use the wwid
+# pvs should find the disk by wwid
+# rename the DEVNAME field
+# pvs should fix DEVNAME field
+
+rm "$DF"
+aux wipefs_a "$DEV1"
+mkdir -p "$SYS_DIR/dev/block/$MAJOR1:$MINOR1/device"
+echo -n "t10.ATA     QEMU HARDDISK                           QM00002            " > "$SYS_DIR/dev/block/$MAJOR1:$MINOR1/device/wwid"
+touch "$DF"
+pvcreate "$DEV1"
+vgcreate $vg1 "$DEV1"
+cat "$DF"
+grep 'IDTYPE=sys_wwid' "$DF" | tee out
+grep "QEMU_HARDDISK" out
+pvs -o+uuid,deviceidtype,deviceid | tee out
+grep "$DEV1" out
+grep sys_wwid out
+grep "QEMU_HARDDISK" out
+sed -e "s|DEVNAME=$DEV1|DEVNAME=/dev/sdx|" "$DF" > tmpdf
+cp tmpdf "$DF"
+cat "$DF"
+pvs -o+uuid,deviceidtype,deviceid "$DEV1"
+grep "DEVNAME=$DEV1" "$DF"
+rm "$SYS_DIR/dev/block/$MAJOR1:$MINOR1/device/wwid"
+cleanup_sysfs
+
+
 
 # TODO: lvmdevices --adddev <dev> --deviceidtype <type> --deviceid <val>
 # This would let the user specify the second naa wwid.