Use dm_is_dm_major instead of local copy.

Allow mapped devices to be used as PVs safely.

WHATS_NEW

@@ -1,5 +1,8 @@
 Version 2.02.00 - 
 ===================================
+  Add DEFS to make.tmpl.
+  Use dm_is_dm_major instead of local copy.
+  Allow mapped devices to be used as PVs.
   Move set_selinux_context into libdevmapper.
   Fix automatic text metadata buffer expansion (using macro).
   Cache formatted text metadata buffer between metadata area writes.

lib/activate/activate.c

@@ -26,6 +26,7 @@
 #include "dev_manager.h"
 #include "str_list.h"
 #include "config.h"
+#include "filter.h"
 
 #include <limits.h>
 #include <fcntl.h>
@@ -144,6 +145,12 @@ int lv_mknodes(struct cmd_context *cmd, const struct logical_volume *lv)
 	return 1;
 }
 
+int pv_uses_vg(struct cmd_context *cmd, struct physical_volume *pv,
+               struct volume_group *vg)
+{
+	return 0;
+}
+
 void activation_exit(void)
 {
 	return;
@@ -790,6 +797,34 @@ int lv_mknodes(struct cmd_context *cmd, const struct logical_volume *lv)
 	return r;
 }
 
+/*
+ * Does PV use VG somewhere in its construction?
+ * Returns 1 on failure.
+ */
+int pv_uses_vg(struct cmd_context *cmd, struct physical_volume *pv,
+               struct volume_group *vg)
+{
+	struct dev_manager *dm;
+	int r;
+
+	if (!activation())
+		return 0;
+
+	if (!dm_is_dm_major(MAJOR(pv->dev->dev)))
+		return 0;
+
+	if (!(dm = dev_manager_create(cmd, vg->name))) {
+		stack;
+		return 1;
+	}
+
+	r = dev_manager_device_uses_vg(dm, pv->dev, vg);
+
+	dev_manager_destroy(dm);
+
+	return r;
+}
+
 void activation_exit(void)
 {
 	dev_manager_exit();

lib/activate/activate.h

@@ -76,4 +76,10 @@ int lv_mirror_percent(struct cmd_context *cmd, struct logical_volume *lv, int wa
 int lvs_in_vg_activated(struct volume_group *vg);
 int lvs_in_vg_opened(struct volume_group *vg);
 
+/*
+ * Returns 1 if PV has a dependency tree that uses anything in VG.
+ */
+int pv_uses_vg(struct cmd_context *cmd, struct physical_volume *pv,
+	       struct volume_group *vg);
+
 #endif

lib/activate/dev_manager.c

@@ -24,6 +24,7 @@
 #include "toolcontext.h"
 #include "targets.h"
 #include "config.h"
+#include "filter.h"
 
 #include <limits.h>
 #include <dirent.h>
@@ -54,6 +55,7 @@
  */
 
 #define MAX_TARGET_PARAMSIZE 50000
+#define UUID_PREFIX "LVM-"
 
 enum {
 	ACTIVE = 0,
@@ -170,14 +172,14 @@ static char *_build_dlid(struct dm_pool *mem, const char *lvid, const char *laye
 	if (!layer)
 		layer = "";
 
-	len = 4 + strlen(lvid) + strlen(layer) + 2;
+	len = sizeof(UUID_PREFIX) + sizeof(union lvid) + strlen(layer);
 
 	if (!(dlid = dm_pool_alloc(mem, len))) {
 		stack;
 		return NULL;
 	}
 
-	sprintf(dlid, "LVM-%s%s%s", lvid, (*layer) ? "-" : "", layer);
+	sprintf(dlid, UUID_PREFIX "%s%s%s", lvid, (*layer) ? "-" : "", layer);
 
 	return dlid;
 }
@@ -2279,7 +2281,7 @@ fail:
 /*
  * Deactivate LV and all devices it references that nothing else has open.
  */
-int dev_manager_deactivate(struct dev_manager *dm, struct logical_volume *lv)
+static int _tree_action(struct dev_manager *dm, struct logical_volume *lv, action_t action)
 {
 	struct deptree *dtree;
 	struct deptree_node *dnode;
@@ -2302,13 +2304,24 @@ int dev_manager_deactivate(struct dev_manager *dm, struct logical_volume *lv)
 	}
 
 	/* Only process nodes with uuid of "LVM-" plus VG id. */
-	if (!dm_deptree_deactivate_children(dnode, dlid, ID_LEN + 4)) {
-		stack;
+	switch(action) {
+	case DEACTIVATE:
+		if (!dm_deptree_deactivate_children(dnode, dlid, ID_LEN + 4)) {
+			stack;
+			goto out;
+		}
+		break;
+	case SUSPEND:
+		if (!dm_deptree_suspend_children(dnode, dlid, ID_LEN + 4)) {
+			stack;
+			goto out;
+		}
+		break;
+	default:
+		log_error("_tree_action: Action %u not supported.", action);
 		goto out;
 	}	
 
-	fs_del_lv(lv);
-
 	r = 1;
 
 out:
@@ -2317,3 +2330,56 @@ out:
 	return r;
 }
 
+int dev_manager_deactivate(struct dev_manager *dm, struct logical_volume *lv)
+{
+	int r;
+
+	r = _tree_action(dm, lv, DEACTIVATE);
+
+	fs_del_lv(lv);
+
+	return r;
+}
+
+/*
+ * Does device use VG somewhere in its construction?
+ * Returns 1 if uncertain.
+ */
+int dev_manager_device_uses_vg(struct dev_manager *dm, struct device *dev,
+			       struct volume_group *vg)
+{
+	struct deptree *dtree;
+	struct deptree_node *dnode;
+	char dlid[sizeof(UUID_PREFIX) + sizeof(struct id) - 1];
+	int r = 1;
+
+	if (!(dtree = dm_deptree_create())) {
+		log_error("partial deptree creation failed");
+		return r;
+	}
+
+	if (!dm_deptree_add_dev(dtree, MAJOR(dev->dev), MINOR(dev->dev))) {
+		log_error("Failed to add device %s (%" PRIu32 ":%" PRIu32") to deptree",
+			  dev_name(dev), (uint32_t) MAJOR(dev->dev), (uint32_t) MINOR(dev->dev));
+		goto out;
+	}
+
+	memcpy(dlid, UUID_PREFIX, sizeof(UUID_PREFIX) - 1);
+	memcpy(dlid + sizeof(UUID_PREFIX) - 1, &vg->id.uuid[0], sizeof(vg->id));
+
+	if (!(dnode = dm_deptree_find_node(dtree, 0, 0))) {
+		log_error("Lost dependency tree root node");
+		goto out;
+	}
+
+	if (dm_deptree_children_use_uuid(dnode, dlid, sizeof(UUID_PREFIX) + sizeof(vg->id) - 1)) {
+		stack;
+		goto out;
+	}
+
+	r = 0;
+
+out:
+	dm_deptree_free(dtree);
+	return r;
+}

lib/activate/dev_manager.h

@@ -17,9 +17,11 @@
 #define _LVM_DEV_MANAGER_H
 
 struct logical_volume;
+struct volume_group;
 struct cmd_context;
 struct dev_manager;
 struct dm_info;
+struct device;
 
 /*
  * Constructor and destructor.
@@ -55,4 +57,7 @@ int dev_manager_lv_rmnodes(const struct logical_volume *lv);
  */
 int dev_manager_execute(struct dev_manager *dm);
 
+int dev_manager_device_uses_vg(struct dev_manager *dm, struct device *dev,
+			       struct volume_group *vg);
+
 #endif

lib/cache/lvmcache.c

@@ -494,8 +494,8 @@ struct lvmcache_info *lvmcache_add(struct labeller *labeller, const char *pvid,
 						 pvid, dev_name(dev),
 						 dev_name(existing->dev));
 				return NULL;
-			} else if (is_dm_major(MAJOR(existing->dev->dev)) &&
-				   !is_dm_major(MAJOR(dev->dev))) {
+			} else if (dm_is_dm_major(MAJOR(existing->dev->dev)) &&
+				   !dm_is_dm_major(MAJOR(dev->dev))) {
 				log_very_verbose("Ignoring duplicate PV %s on "
 						 "%s - using dm %s",
 						 pvid, dev_name(dev),
@@ -507,8 +507,8 @@ struct lvmcache_info *lvmcache_add(struct labeller *labeller, const char *pvid,
 						 "using md %s", pvid,
 						 dev_name(existing->dev),
 						 dev_name(dev));
-			else if (!is_dm_major(MAJOR(existing->dev->dev)) &&
-				 is_dm_major(MAJOR(dev->dev)))
+			else if (!dm_is_dm_major(MAJOR(existing->dev->dev)) &&
+				 dm_is_dm_major(MAJOR(dev->dev)))
 				log_very_verbose("Duplicate PV %s on %s - "
 						 "using dm %s", pvid,
 						 dev_name(existing->dev),

lib/filters/filter.c

@@ -28,7 +28,6 @@
 
 #define NUMBER_OF_MAJORS 4096
 
-/* FIXME Make this sparse */
 /* 0 means LVM won't use this major number. */
 static int _max_partitions_by_major[NUMBER_OF_MAJORS];
 
@@ -38,18 +37,12 @@ typedef struct {
 } device_info_t;
 
 static int _md_major = -1;
-static dm_bitset_t _dm_bitset;
 
 int md_major(void)
 {
 	return _md_major;
 }
 
-int is_dm_major(int major)
-{
-	return dm_bit(_dm_bitset, major) ? 1 : 0;
-}
-
 /*
  * Devices are only checked for partition tables if their minor number
  * is a multiple of the number corresponding to their type below
@@ -78,6 +71,7 @@ static const device_info_t device_info[] = {
 	{"gnbd", 1},		/* Network block device */
 	{"ramdisk", 1},		/* RAM disk */
 	{"aoe", 16},		/* ATA over Ethernet */
+	{"device-mapper", 1},	/* Other mapped devices */
 	{NULL, 0}
 };
 
@@ -187,11 +181,6 @@ static int _scan_proc_dev(const char *proc, const struct config_node *cn)
 		if (!strncmp("md", line + i, 2) && isspace(*(line + i + 2)))
 			_md_major = line_maj;
 
-		/* Look for dm devices */
-		if (!strncmp("device-mapper", line + i, 13) &&
-		    isspace(*(line + i + 13)))
-			dm_bit_set(_dm_bitset, line_maj);
-
 		/* Go through the valid device names and if there is a
 		   match store max number of partitions */
 		for (j = 0; device_info[j].name != NULL; j++) {
@@ -262,12 +251,6 @@ struct dev_filter *lvm_type_filter_create(const char *proc,
 	f->destroy = lvm_type_filter_destroy;
 	f->private = NULL;
 
-	if (!(_dm_bitset = dm_bitset_create(NULL, NUMBER_OF_MAJORS))) {
-		stack;
-		dm_free(f);
-		return NULL;
-	}
-
 	if (!_scan_proc_dev(proc, cn)) {
 		stack;
 		return NULL;
@@ -278,7 +261,6 @@ struct dev_filter *lvm_type_filter_create(const char *proc,
 
 void lvm_type_filter_destroy(struct dev_filter *f)
 {
-	dm_bitset_destroy(_dm_bitset);
 	dm_free(f);
 	return;
 }

lib/filters/filter.h

@@ -36,7 +36,6 @@ struct dev_filter *lvm_type_filter_create(const char *proc,
 void lvm_type_filter_destroy(struct dev_filter *f);
 
 int md_major(void);
-int is_dm_major(int major);
 int max_partitions(int major);
 
 #endif

lib/metadata/lv_manip.c

@@ -229,6 +229,9 @@ void set_lv_segment_area_lv(struct lv_segment *seg, uint32_t area_num,
 	lv->status |= flags;
 }
 
+static int _lv_segment_add_areas(struct logical_volume *lv,
+				 struct lv_segment *seg,
+				 uint32_t new_area_count) __attribute__ ((unused));
 /*
  * Prepare for adding parallel areas to an existing segment.
  */

lib/metadata/metadata.c

@@ -22,6 +22,7 @@
 #include "memlock.h"
 #include "str_list.h"
 #include "pv_alloc.h"
+#include "activate.h"
 
 static int _add_pv_to_vg(struct format_instance *fid, struct volume_group *vg,
 			 const char *pv_name)
@@ -58,6 +59,13 @@ static int _add_pv_to_vg(struct format_instance *fid, struct volume_group *vg,
 		return 0;
 	}
 
+	/* Ensure PV doesn't depend on another PV already in the VG */
+	if (pv_uses_vg(fid->fmt->cmd, pv, vg)) {
+		log_error("Physical volume %s might be constructed from same "
+			  "volume group %s", pv_name, vg->name);
+		return 0;
+	}
+
 	if (!(pv->vg_name = dm_pool_strdup(mem, vg->name))) {
 		log_error("vg->name allocation failed for '%s'", pv_name);
 		return 0;

tools/vgmerge.c

@@ -20,6 +20,7 @@ static int _vgmerge_single(struct cmd_context *cmd, const char *vg_name_to,
 {
 	struct volume_group *vg_to, *vg_from;
 	struct lv_list *lvl1, *lvl2;
+	struct pv_list *pvl;
 	int active;
 	int consistent = 1;
 
@@ -122,6 +123,25 @@ static int _vgmerge_single(struct cmd_context *cmd, const char *vg_name_to,
 		}
 	}
 
+	/* Check no PVs are constructed from either VG */
+	list_iterate_items(pvl, &vg_to->pvs) {
+		if (pv_uses_vg(cmd, pvl->pv, vg_from)) {
+			log_error("Physical volume %s might be constructed "
+				  "from same volume group %s.",
+				  dev_name(pvl->pv->dev), vg_from->name);
+			goto error;
+		}
+	}
+
+	list_iterate_items(pvl, &vg_from->pvs) {
+		if (pv_uses_vg(cmd, pvl->pv, vg_to)) {
+			log_error("Physical volume %s might be constructed "
+				  "from same volume group %s.",
+				  dev_name(pvl->pv->dev), vg_to->name);
+			goto error;
+		}
+	}
+
 	/* FIXME List arg: vg_show_with_pv_and_lv(vg_to); */
 
 	if (!archive(vg_from) || !archive(vg_to))