lvm2/tools/lvconvert.c

/*
 * Copyright (C) 2005-2013 Red Hat, Inc. All rights reserved.
 *
 * This file is part of LVM2.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU Lesser General Public License v.2.1.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "tools.h"
#include "polldaemon.h"
#include "lv_alloc.h"

struct lvconvert_params {
	int force;
	int snapshot;
	int splitsnapshot;
	int merge;
	int merge_mirror;
	int poolmetadataspare;
	int thin;
	int yes;
	int zero;

	const char *origin;
	const char *cachepool;
	const char *lv_name;
	const char *lv_split_name;
	const char *lv_name_full;
	const char *vg_name;
	int wait_completion;
	int need_polling;

	int thin_chunk_size_calc_policy;
	uint32_t chunk_size;
	uint32_t region_size;

	uint32_t mirrors;
	sign_t mirrors_sign;
	uint32_t keep_mimages;
	uint32_t stripes;
	uint32_t stripe_size;
	uint32_t read_ahead;
	uint32_t feature_flags; /* cache_pool */

	const struct segment_type *segtype;
	unsigned target_attr;

	alloc_policy_t alloc;

	int pv_count;
	char **pvs;
	struct dm_list *pvh;

	int replace_pv_count;
	char **replace_pvs;
	struct dm_list *replace_pvh;

	struct logical_volume *lv_to_poll;

	int passed_args;
	uint64_t poolmetadata_size;
	const char *origin_lv_name;
	const char *pool_data_lv_name;
	const char *pool_metadata_lv_name;
	thin_discards_t discards;
};

static int _lvconvert_name_params(struct lvconvert_params *lp,
				  struct cmd_context *cmd,
				  int *pargc, char ***pargv)
{
	char *ptr;
	const char *vg_name = NULL;
	const char *tmp_str;

	if (lp->merge)
		return 1;

	if (lp->snapshot) {
		if (!*pargc) {
			log_error("Please specify a logical volume to act as "
				  "the snapshot origin.");
			return 0;
		}

		lp->origin = *pargv[0];
		(*pargv)++, (*pargc)--;
		if (!(lp->vg_name = extract_vgname(cmd, lp->origin))) {
			log_error("The origin name should include the "
				  "volume group.");
			return 0;
		}

		/* Strip the volume group from the origin */
		if ((ptr = strrchr(lp->origin, (int) '/')))
			lp->origin = ptr + 1;
	}

	if (lp->pool_data_lv_name) {
		if (*pargc) {
			if (!lp->thin) {
				log_error("More then one logical volume name specified.");
				return 0;
			}
		} else {
			if (lp->thin) {
				log_error("External thin volume name is missing.");
				return 0;
			}

			if (!lp->vg_name || !validate_name(lp->vg_name)) {
				log_error("Please provide a valid volume group name.");
				return 0;
			}

			lp->lv_name = lp->pool_data_lv_name;
			return 1;
		}
	}

	if (lp->origin_lv_name) {
		/* FIXME: Using generic routine */
		if (strchr(lp->origin_lv_name, '/')) {
			if (!(lp->vg_name = extract_vgname(cmd, lp->origin_lv_name)))
				return_0;
			/* Strip VG from origin_lv_name */
			if ((tmp_str = strrchr(lp->origin_lv_name, '/')))
				lp->origin_lv_name = tmp_str + 1;
		}
	}

	if (!*pargc) {
		log_error("Please provide logical volume path");
		return 0;
	}

	lp->lv_name = lp->lv_name_full = (*pargv)[0];
	(*pargv)++, (*pargc)--;

	if (strchr(lp->lv_name_full, '/') &&
	    (vg_name = extract_vgname(cmd, lp->lv_name_full)) &&
	    lp->vg_name && strcmp(vg_name, lp->vg_name)) {
		log_error("Please use a single volume group name "
			  "(\"%s\" or \"%s\")", vg_name, lp->vg_name);
		return 0;
	}

	if (!lp->vg_name)
		lp->vg_name = vg_name;

	if (!validate_name(lp->vg_name)) {
		log_error("Please provide a valid volume group name");
		return 0;
	}

	if ((ptr = strrchr(lp->lv_name_full, '/')))
		lp->lv_name = ptr + 1;

	if (!lp->merge_mirror &&
	    !strstr(lp->lv_name, "_tdata") &&
	    !strstr(lp->lv_name, "_tmeta") &&
	    !apply_lvname_restrictions(lp->lv_name))
		return_0;

	if (*pargc && lp->snapshot) {
		log_error("Too many arguments provided for snapshots");
		return 0;
	}

	if (lp->splitsnapshot && *pargc) {
		log_error("Too many arguments provided with --splitsnapshot.");
		return 0;
	}

	if (lp->pool_data_lv_name && lp->lv_name && lp->poolmetadata_size) {
		log_error("Please specify either metadata logical volume or its size.");
		return 0;
	}

	return 1;
}

static int _check_conversion_type(struct cmd_context *cmd, const char *type_str)
{
	if (!type_str || !*type_str)
		return 1;

	if (!strcmp(type_str, "mirror")) {
		if (!arg_count(cmd, mirrors_ARG)) {
			log_error("--type mirror requires -m/--mirrors");
			return 0;
		}
		return 1;
	}

	/* FIXME: Check thin-pool and thin more thoroughly! */
	if (!strcmp(type_str, "snapshot") ||
	    !strncmp(type_str, "raid", 4) ||
	    !strcmp(type_str, "cache-pool") || !strcmp(type_str, "cache") ||
	    !strcmp(type_str, "thin-pool") || !strcmp(type_str, "thin"))
		return 1;

	log_error("Conversion using --type %s is not supported.", type_str);
	return 0;
}

/* -s/--snapshot and --type snapshot are synonyms */
#define snapshot_type_requested(cmd,type_str) (arg_count(cmd, snapshot_ARG) || \
					       !strcmp(type_str, "snapshot"))
/* mirror/raid* (1,10,4,5,6 and their variants) reshape */
#define mirror_or_raid_type_requested(cmd,type_str) (arg_count(cmd, mirrors_ARG) || \
						     !strncmp(type_str, "raid", 4))

static int _read_params(struct lvconvert_params *lp, struct cmd_context *cmd,
			int argc, char **argv)
{
	int i;
	int cache_pool = 0;
	const char *tmp_str;
	struct arg_value_group_list *group;
	int region_size;
	int pagesize = lvm_getpagesize();
	const char *type_str = arg_str_value(cmd, type_ARG, "");

	memset(lp, 0, sizeof(*lp));
	lp->target_attr = ~0;

	if (!_check_conversion_type(cmd, type_str))
		return_0;

	if (arg_count(cmd, splitsnapshot_ARG))
		lp->splitsnapshot = 1;

	if ((snapshot_type_requested(cmd, type_str) || arg_count(cmd, merge_ARG)) &&
	    (arg_count(cmd, mirrorlog_ARG) || mirror_or_raid_type_requested(cmd, type_str) ||
	     arg_count(cmd, repair_ARG) || arg_count(cmd, thinpool_ARG))) {
		log_error("--snapshot/--type snapshot or --merge argument "
			  "cannot be mixed with --mirrors/--type mirror/--type raid*, "
			  "--mirrorlog, --repair or --thinpool.");
		return 0;
	}

	if ((arg_count(cmd, stripes_long_ARG) || arg_count(cmd, stripesize_ARG)) &&
	    !(mirror_or_raid_type_requested(cmd, type_str) ||
	      arg_count(cmd, repair_ARG) ||
	      arg_count(cmd, thinpool_ARG))) {
		log_error("--stripes or --stripesize argument is only valid "
			  "with --mirrors/--type mirror/--type raid*, --repair and --thinpool");
		return 0;
	}

	if (!strcmp(type_str, "cache-pool")) {
		cache_pool = 1;
		if ((tmp_str = arg_str_value(cmd, cachemode_ARG, NULL))) {
			if (!strcmp(tmp_str, "writeback"))
				lp->feature_flags |= DM_CACHE_FEATURE_WRITEBACK;
			else if (!strcmp(tmp_str, "writethrough"))
				lp->feature_flags |= DM_CACHE_FEATURE_WRITETHROUGH;
			else {
				log_error("Unknown cachemode argument");
				return 0;
			}
		}
	}

	if (!arg_count(cmd, background_ARG))
		lp->wait_completion = 1;

	if (snapshot_type_requested(cmd, type_str))
		lp->snapshot = 1;

	if (snapshot_type_requested(cmd, type_str) && arg_count(cmd, merge_ARG)) {
		log_error("--snapshot and --merge are mutually exclusive");
		return 0;
	}

	if (arg_count(cmd, splitmirrors_ARG) && mirror_or_raid_type_requested(cmd, type_str)) {
		log_error("--mirrors/--type mirror/--type raid* and --splitmirrors are "
			  "mutually exclusive");
		return 0;
	}

	if (arg_count(cmd, thin_ARG))
		lp->thin = 1;

	if (arg_count(cmd, cachepool_ARG)) {
		if (strcmp(type_str, "cache")) {
			log_error("--cachepool argument is only valid with "
				  " the \"cache\" segment type");
			return 0;
		}
		lp->cachepool = arg_str_value(cmd, cachepool_ARG, NULL);
	} else if (arg_count(cmd, thinpool_ARG) || cache_pool) {
		if (arg_count(cmd, merge_ARG)) {
			log_error("--%spool and --merge are mutually exlusive.",
				  cache_pool ? "type cache_" : "thin");
			return 0;
		}
		if (mirror_or_raid_type_requested(cmd, type_str)) {
			log_error("--%spool and --mirrors/--type mirror/--type raid* are mutually exlusive.", cache_pool ? "type cache_" : "thin");
			return 0;
		}
		if (arg_count(cmd, repair_ARG)) {
			log_error("--%spool and --repair are mutually exlusive.",
				  cache_pool ? "type cache_" : "thin");
			return 0;
		}
		if (snapshot_type_requested(cmd, type_str)) {
			log_error("--%spool and --snapshot/--type snapshot are mutually exlusive.", cache_pool ? "type cache_" : "thin");
			return 0;
		}
		if (arg_count(cmd, splitmirrors_ARG)) {
			log_error("--%spool and --splitmirrors are mutually exlusive.", cache_pool ? "type cache_" : "thin");
			return 0;
		}
		if (!cache_pool)
			lp->discards = (thin_discards_t) arg_uint_value(cmd, discards_ARG, THIN_DISCARDS_PASSDOWN);
	} else if (lp->thin) {
		log_error("--thin is only valid with --thinpool.");
		return 0;
	} else if (arg_count(cmd, discards_ARG)) {
		log_error("--discards is only valid with --thinpool.");
		return 0;
	} else if (arg_count(cmd, poolmetadataspare_ARG)) {
		log_error("--poolmetadataspare is only valid with --thinpool.");
		return 0;
	}

	/*
	 * The '--splitmirrors n' argument is equivalent to '--mirrors -n'
	 * (note the minus sign), except that it signifies the additional
	 * intent to keep the mimage that is detached, rather than
	 * discarding it.
	 */
	if (arg_count(cmd, splitmirrors_ARG)) {
		if (!arg_count(cmd, name_ARG) &&
		    !arg_count(cmd, trackchanges_ARG)) {
			log_error("Please name the new logical volume using '--name'");
			return 0;
		}

		lp->lv_split_name = arg_value(cmd, name_ARG);
		if (lp->lv_split_name) {
			if (strchr(lp->lv_split_name, '/')) {
				if (!(lp->vg_name = extract_vgname(cmd, lp->lv_split_name)))
					return_0;

				/* Strip VG from lv_split_name */
				if ((tmp_str = strrchr(lp->lv_split_name, '/')))
					lp->lv_split_name = tmp_str + 1;
			}

			if (!apply_lvname_restrictions(lp->lv_split_name))
				return_0;
		}

		lp->keep_mimages = 1;
		lp->mirrors = arg_uint_value(cmd, splitmirrors_ARG, 0);
		lp->mirrors_sign = SIGN_MINUS;
	} else if (arg_count(cmd, name_ARG)) {
		log_error("The 'name' argument is only valid"
			  " with --splitmirrors");
		return 0;
	}

	if (arg_count(cmd, merge_ARG)) {
		if ((argc == 1) && strstr(argv[0], "_rimage_"))
			lp->merge_mirror = 1;
		else
			lp->merge = 1;
	}

	if (arg_count(cmd, mirrors_ARG)) {
		/*
		 * --splitmirrors has been chosen as the mechanism for
		 * specifying the intent of detaching and keeping a mimage
		 * versus an additional qualifying argument being added here.
		 */
		lp->mirrors = arg_uint_value(cmd, mirrors_ARG, 0);
		lp->mirrors_sign = arg_sign_value(cmd, mirrors_ARG, SIGN_NONE);
	}

	if (lp->splitsnapshot &&
	    (lp->snapshot || lp->thin || lp->merge || lp->merge_mirror || arg_count(cmd, thinpool_ARG) ||
	     arg_count(cmd, mirrors_ARG) || arg_count(cmd, repair_ARG) || arg_count(cmd, replace_ARG) ||
	     arg_count(cmd, chunksize_ARG) || arg_count(cmd, zero_ARG) || arg_count(cmd, regionsize_ARG) ||
	     arg_count(cmd, poolmetadata_ARG) || arg_count(cmd, poolmetadatasize_ARG) ||
	     arg_count(cmd, readahead_ARG) || arg_count(cmd, stripes_long_ARG) ||
	     arg_count(cmd, stripesize_ARG) || arg_count(cmd, background_ARG) ||
	     arg_count(cmd, interval_ARG) || arg_count(cmd, type_ARG) || arg_count(cmd, alloc_ARG) ||
	     arg_count(cmd, corelog_ARG) || arg_count(cmd, mirrorlog_ARG) ||
	     arg_count(cmd, splitmirrors_ARG) || arg_count(cmd, originname_ARG) ||
	     arg_count(cmd, trackchanges_ARG) || arg_count(cmd, use_policies_ARG))) {
		log_error("Incompatible arguments supplied with --splitsnapshot.");
		return 0;
	}

	lp->alloc = (alloc_policy_t) arg_uint_value(cmd, alloc_ARG, ALLOC_INHERIT);

	/* There are six types of lvconvert. */
	if (lp->merge) {	/* Snapshot merge */
		if (arg_count(cmd, regionsize_ARG) || arg_count(cmd, chunksize_ARG) ||
		    arg_count(cmd, zero_ARG) || arg_count(cmd, regionsize_ARG) ||
		    arg_count(cmd, poolmetadata_ARG) || arg_count(cmd, poolmetadatasize_ARG) ||
		    arg_count(cmd, readahead_ARG) ||
		    arg_count(cmd, stripes_long_ARG) || arg_count(cmd, stripesize_ARG)) {
			log_error("Only --background and --interval are valid "
				  "arguments for snapshot merge");
			return 0;
		}

		if (!(lp->segtype = get_segtype_from_string(cmd, "snapshot")))
			return_0;
	} else if (lp->splitsnapshot)	/* Destroy snapshot retaining cow as separate LV */
		;
	else if (lp->snapshot) {	/* Snapshot creation from pre-existing cow */
		if (arg_count(cmd, regionsize_ARG)) {
			log_error("--regionsize is only available with mirrors");
			return 0;
		}

		if (arg_count(cmd, stripesize_ARG) || arg_count(cmd, stripes_long_ARG)) {
			log_error("--stripes and --stripesize are only available with striped mirrors");
			return 0;
		}

		if (arg_sign_value(cmd, chunksize_ARG, SIGN_NONE) == SIGN_MINUS) {
			log_error("Negative chunk size is invalid");
			return 0;
		}
		lp->chunk_size = arg_uint_value(cmd, chunksize_ARG, 8);
		if (lp->chunk_size < 8 || lp->chunk_size > 1024 ||
		    (lp->chunk_size & (lp->chunk_size - 1))) {
			log_error("Chunk size must be a power of 2 in the "
				  "range 4K to 512K");
			return 0;
		}
		log_verbose("Setting chunksize to %d sectors.", lp->chunk_size);

		if (!(lp->segtype = get_segtype_from_string(cmd, "snapshot")))
			return_0;

		lp->zero = strcmp(arg_str_value(cmd, zero_ARG,
						(lp->segtype->flags &
						 SEG_CANNOT_BE_ZEROED) ?
						"n" : "y"), "n");

	} else if (arg_count(cmd, replace_ARG)) { /* RAID device replacement */
		lp->replace_pv_count = arg_count(cmd, replace_ARG);
		lp->replace_pvs = dm_pool_alloc(cmd->mem, sizeof(char *) * lp->replace_pv_count);
		if (!lp->replace_pvs)
			return_0;

		i = 0;
		dm_list_iterate_items(group, &cmd->arg_value_groups) {
			if (!grouped_arg_is_set(group->arg_values, replace_ARG))
				continue;
			if (!(tmp_str = grouped_arg_str_value(group->arg_values,
							      replace_ARG,
							      NULL))) {
				log_error("Failed to get '--replace' argument");
				return 0;
			}
			if (!(lp->replace_pvs[i++] = dm_pool_strdup(cmd->mem,
								    tmp_str)))
				return_0;
		}
	} else if (arg_count(cmd, thinpool_ARG) || cache_pool) {
		if (cache_pool) {
			if (!argc) {
				log_error("Please specify the pool data LV.");
				return 0;
			}
			lp->pool_data_lv_name = argv[0];
			argv++, argc--;
		} else if (!(lp->pool_data_lv_name = arg_str_value(cmd, thinpool_ARG, NULL))) {
			log_error("Missing pool logical volume name.");
			return 0;
		}

		if (arg_count(cmd, poolmetadata_ARG)) {
			if (arg_count(cmd, poolmetadatasize_ARG)) {
				log_error("--poolmetadatasize is invalid with --poolmetadata.");
				return 0;
			}
			if (arg_count(cmd, stripesize_ARG) || arg_count(cmd, stripes_long_ARG)) {
				log_error("Can't use --stripes and --stripesize with --poolmetadata.");
				return 0;
			}

			if (arg_count(cmd, readahead_ARG)) {
				log_error("Can't use --readahead with --poolmetadata.");
				return 0;
			}
			lp->pool_metadata_lv_name = arg_str_value(cmd, poolmetadata_ARG, "");
		}

		/* Hmm _read_activation_params */
		lp->read_ahead = arg_uint_value(cmd, readahead_ARG,
						cmd->default_settings.read_ahead);

		/* If pool_data_lv_name contains VG name, extract it. */
		if ((tmp_str = strchr(lp->pool_data_lv_name, (int) '/'))) {
			if (!(lp->vg_name = extract_vgname(cmd, lp->pool_data_lv_name)))
				return 0;
			/* Strip VG from pool */
			lp->pool_data_lv_name = tmp_str + 1;
		}

		if (arg_count(cmd, originname_ARG)) {
			if (!(lp->origin_lv_name = arg_str_value(cmd, originname_ARG, NULL))) {
				log_error("--originname is invalid.");
				return 0;
			}
		}

		lp->segtype = get_segtype_from_string(cmd, arg_str_value(cmd, type_ARG, cache_pool ? "cache-pool" : "thin-pool"));
		if (!lp->segtype)
			return_0;
	} else { /* Mirrors (and some RAID functions) */
		if (arg_count(cmd, chunksize_ARG)) {
			log_error("--chunksize is only available with "
				  "snapshots or thin pools.");
			return 0;
		}

		if (arg_count(cmd, zero_ARG)) {
			log_error("--zero is only available with snapshots or thin pools.");
			return 0;
		}

		/*
	 	 * --regionsize is only valid if converting an LV into a mirror.
	 	 * Checked when we know the state of the LV being converted.
	 	 */

		if (arg_count(cmd, regionsize_ARG)) {
			if (arg_sign_value(cmd, regionsize_ARG, SIGN_NONE) ==
				    SIGN_MINUS) {
				log_error("Negative regionsize is invalid");
				return 0;
			}
			lp->region_size = arg_uint_value(cmd, regionsize_ARG, 0);
		} else {
			region_size = get_default_region_size(cmd);
			if (region_size < 0) {
				log_error("Negative regionsize in "
					  "configuration file is invalid");
				return 0;
			}
			lp->region_size = region_size;
		}

		if (lp->region_size % (pagesize >> SECTOR_SHIFT)) {
			log_error("Region size (%" PRIu32 ") must be "
				  "a multiple of machine memory "
				  "page size (%d)",
				  lp->region_size, pagesize >> SECTOR_SHIFT);
			return 0;
		}

		if (lp->region_size & (lp->region_size - 1)) {
			log_error("Region size (%" PRIu32
				  ") must be a power of 2", lp->region_size);
			return 0;
		}

		if (!lp->region_size) {
			log_error("Non-zero region size must be supplied.");
			return 0;
		}

		/* Default is never striped, regardless of existing LV configuration. */
		if (!get_stripe_params(cmd, &lp->stripes, &lp->stripe_size))
			return_0;

		if (arg_count(cmd, mirrors_ARG) && !lp->mirrors) {
			/* down-converting to linear/stripe? */
			if (!(lp->segtype =
			      get_segtype_from_string(cmd, "striped")))
				return_0;
		} else if (arg_count(cmd, type_ARG)) {
			/* changing mirror type? */
			if (!(lp->segtype = get_segtype_from_string(cmd, arg_str_value(cmd, type_ARG, find_config_tree_str(cmd, global_mirror_segtype_default_CFG, NULL)))))
				return_0;
		} /* else segtype will default to current type */
	}

	/* TODO: default in lvm.conf ? */
	lp->poolmetadataspare = arg_int_value(cmd, poolmetadataspare_ARG,
					      DEFAULT_POOL_METADATA_SPARE);
	lp->force = arg_count(cmd, force_ARG);
	lp->yes = arg_count(cmd, yes_ARG);

	if (activation() && lp->segtype && lp->segtype->ops->target_present &&
	    !lp->segtype->ops->target_present(cmd, NULL, &lp->target_attr)) {
		log_error("%s: Required device-mapper target(s) not "
			  "detected in your kernel", lp->segtype->name);
		return 0;
	}

	if (!_lvconvert_name_params(lp, cmd, &argc, &argv))
		return_0;

	lp->pv_count = argc;
	lp->pvs = argv;

	return 1;
}

static struct volume_group *_get_lvconvert_vg(struct cmd_context *cmd,
					      const char *name,
					      const char *uuid __attribute__((unused)))
{
	dev_close_all();

	if (name && !strchr(name, '/'))
		return vg_read_for_update(cmd, name, NULL, 0);

	/* 'name' is the full LV name; must extract_vgname() */
	return vg_read_for_update(cmd, extract_vgname(cmd, name),
				  NULL, 0);
}

static struct logical_volume *_get_lvconvert_lv(struct cmd_context *cmd __attribute__((unused)),
						struct volume_group *vg,
						const char *name,
						const char *uuid,
						uint64_t lv_type __attribute__((unused)))
{
	struct logical_volume *lv = find_lv(vg, name);

	if (!lv || (uuid && strcmp(uuid, (char *)&lv->lvid)))
		return NULL;

	return lv;
}

static int _reload_lv(struct cmd_context *cmd,
                      struct volume_group *vg,
		      struct logical_volume *lv)
{
	int r = 0;

	log_very_verbose("Updating logical volume \"%s\" on disk(s)", lv->name);

	if (!vg_write(vg))
		return_0;

	if (!suspend_lv(cmd, lv)) {
		log_error("Failed to lock %s", lv->name);
		vg_revert(vg);
		if (!resume_lv(cmd, lv))
			stack;
		goto out;
	}

	if (!vg_commit(vg)) {
		vg_revert(vg);
		if (!resume_lv(cmd, lv))
			stack;
		goto_out;
	}

	log_very_verbose("Updating \"%s\" in kernel", lv->name);

	if (!resume_lv(cmd, lv)) {
		log_error("Problem reactivating %s", lv->name);
		goto out;
	}

	r = 1;
	backup(vg);
out:
	return r;
}

static int _finish_lvconvert_mirror(struct cmd_context *cmd,
				    struct volume_group *vg,
				    struct logical_volume *lv,
				    struct dm_list *lvs_changed __attribute__((unused)))
{
	if (!(lv->status & CONVERTING))
		return 1;

	if (!collapse_mirrored_lv(lv)) {
		log_error("Failed to remove temporary sync layer.");
		return 0;
	}

	lv->status &= ~CONVERTING;

	log_very_verbose("Updating logical volume \"%s\" on disk(s)", lv->name);

	if (!(_reload_lv(cmd, vg, lv)))
		return_0;

	log_print_unless_silent("Logical volume %s converted.", lv->name);

	return 1;
}

/* Swap lvid and LV names */
static int _swap_lv_identifiers(struct cmd_context *cmd,
				struct logical_volume *a, struct logical_volume *b)
{
	union lvid lvid;
	const char *name;

	lvid = a->lvid;
	a->lvid = b->lvid;
	b->lvid = lvid;

	name = a->name;
	a->name = b->name;
	if (!lv_rename_update(cmd, b, name, 0))
		return_0;

	return 1;
}

static void _move_lv_attributes(struct logical_volume *to, struct logical_volume *from)
{
	/* Maybe move this code into _finish_thin_merge() */
	to->status = from->status; // FIXME maybe some masking ?
	to->alloc = from->alloc;
	to->profile = from->profile;
	to->read_ahead = from->read_ahead;
	to->major = from->major;
	to->minor = from->minor;
	to->timestamp = from->timestamp;
	to->hostname = from->hostname;

	/* Move tags */
	dm_list_init(&to->tags);
	dm_list_splice(&to->tags, &from->tags);

	/* Anything else to preserve? */
}

/* Finalise merging of lv into merge_lv */
static int _finish_thin_merge(struct cmd_context *cmd,
			      struct logical_volume *merge_lv,
			      struct logical_volume *lv)
{
	if (!_swap_lv_identifiers(cmd, merge_lv, lv)) {
		log_error("Failed to swap %s with merging %s.",
			  lv->name, merge_lv->name);
		return 0;
	}

	/* Preserve origins' attributes */
	_move_lv_attributes(lv, merge_lv);

	/* Removed LV has to be visible */
	if (!lv_remove_single(cmd, merge_lv, DONT_PROMPT, 1))
		return_0;

	return 1;
}

static int _finish_lvconvert_merge(struct cmd_context *cmd,
				   struct volume_group *vg,
				   struct logical_volume *lv,
				   struct dm_list *lvs_changed __attribute__((unused)))
{
	struct lv_segment *snap_seg = find_snapshot(lv);

	if (!lv_is_merging_origin(lv)) {
		log_error("Logical volume %s has no merging snapshot.", lv->name);
		return 0;
	}

	log_print_unless_silent("Merge of snapshot into logical volume %s has finished.", lv->name);

	if (seg_is_thin_volume(snap_seg)) {
		clear_snapshot_merge(lv);

		if (!_finish_thin_merge(cmd, lv, snap_seg->lv))
			return_0;

	} else if (!lv_remove_single(cmd, snap_seg->cow, DONT_PROMPT, 0)) {
		log_error("Could not remove snapshot %s merged into %s.",
			  snap_seg->cow->name, lv->name);
		return 0;
	}

	return 1;
}

static progress_t _poll_merge_progress(struct cmd_context *cmd,
				       struct logical_volume *lv,
				       const char *name __attribute__((unused)),
				       struct daemon_parms *parms)
{
	percent_t percent = PERCENT_0;

	if (!lv_snapshot_percent(lv, &percent)) {
		log_error("%s: Failed query for merging percentage. Aborting merge.", lv->name);
		return PROGRESS_CHECK_FAILED;
	} else if (percent == PERCENT_INVALID) {
		log_error("%s: Merging snapshot invalidated. Aborting merge.", lv->name);
		return PROGRESS_CHECK_FAILED;
	} else if (percent == PERCENT_MERGE_FAILED) {
		log_error("%s: Merge failed. Retry merge or inspect manually.", lv->name);
		return PROGRESS_CHECK_FAILED;
	}

	if (parms->progress_display)
		log_print_unless_silent("%s: %s: %.1f%%", lv->name, parms->progress_title,
					100.0 - percent_to_float(percent));
	else
		log_verbose("%s: %s: %.1f%%", lv->name, parms->progress_title,
			    100.0 - percent_to_float(percent));

	if (percent == PERCENT_0)
		return PROGRESS_FINISHED_ALL;

	return PROGRESS_UNFINISHED;
}

static progress_t _poll_thin_merge_progress(struct cmd_context *cmd,
					    struct logical_volume *lv,
					    const char *name __attribute__((unused)),
					    struct daemon_parms *parms)
{
	uint32_t device_id;

	if (!lv_thin_device_id(lv, &device_id)) {
		stack;
		return PROGRESS_CHECK_FAILED;
	}

	/*
	 * There is no need to poll more than once,
	 * a thin snapshot merge is immediate.
	 */

	if (device_id != find_snapshot(lv)->device_id) {
		log_error("LV %s is not merged.", lv->name);
		return PROGRESS_CHECK_FAILED;
	}

	return PROGRESS_FINISHED_ALL; /* Merging happend */
}

static struct poll_functions _lvconvert_mirror_fns = {
	.get_copy_vg = _get_lvconvert_vg,
	.get_copy_lv = _get_lvconvert_lv,
	.poll_progress = poll_mirror_progress,
	.finish_copy = _finish_lvconvert_mirror,
};

static struct poll_functions _lvconvert_merge_fns = {
	.get_copy_vg = _get_lvconvert_vg,
	.get_copy_lv = _get_lvconvert_lv,
	.poll_progress = _poll_merge_progress,
	.finish_copy = _finish_lvconvert_merge,
};

static struct poll_functions _lvconvert_thin_merge_fns = {
	.get_copy_vg = _get_lvconvert_vg,
	.get_copy_lv = _get_lvconvert_lv,
	.poll_progress = _poll_thin_merge_progress,
	.finish_copy = _finish_lvconvert_merge,
};

int lvconvert_poll(struct cmd_context *cmd, struct logical_volume *lv,
		   unsigned background)
{
	/*
	 * FIXME allocate an "object key" structure with split
	 * out members (vg_name, lv_name, uuid, etc) and pass that
	 * around the lvconvert and polldaemon code
	 * - will avoid needless work, e.g. extract_vgname()
	 * - unfortunately there are enough overloaded "name" dragons in
	 *   the polldaemon, lvconvert, pvmove code that a comprehensive
	 *   audit/rework is needed
	 */
	int len = strlen(lv->vg->name) + strlen(lv->name) + 2;
	char *uuid = alloca(sizeof(lv->lvid));
	char *lv_full_name = alloca(len);

	if (!uuid || !lv_full_name)
		return_0;

	if (dm_snprintf(lv_full_name, len, "%s/%s", lv->vg->name, lv->name) < 0)
		return_0;

	memcpy(uuid, &lv->lvid, sizeof(lv->lvid));

	if (lv_is_merging_origin(lv))
		return poll_daemon(cmd, lv_full_name, uuid, background, 0,
				   seg_is_thin_volume(find_snapshot(lv)) ?
				   &_lvconvert_thin_merge_fns : &_lvconvert_merge_fns,
				   "Merged");

	return poll_daemon(cmd, lv_full_name, uuid, background, 0,
			   &_lvconvert_mirror_fns, "Converted");
}

static int _insert_lvconvert_layer(struct cmd_context *cmd,
				   struct logical_volume *lv)
{
	char *format, *layer_name;
	size_t len;
	int i;

	/*
 	 * We would like to give the same number for this layer
 	 * and the newly added mimage.
 	 * However, LV name of newly added mimage is determined *after*
	 * the LV name of this layer is determined.
	 *
	 * So, use generate_lv_name() to generate mimage name first
	 * and take the number from it.
	 */

	len = strlen(lv->name) + 32;
	if (!(format = alloca(len)) ||
	    !(layer_name = alloca(len)) ||
	    dm_snprintf(format, len, "%s_mimage_%%d", lv->name) < 0) {
		log_error("lvconvert: layer name allocation failed.");
		return 0;
	}

	if (!generate_lv_name(lv->vg, format, layer_name, len) ||
	    sscanf(layer_name, format, &i) != 1) {
		log_error("lvconvert: layer name generation failed.");
		return 0;
	}

	if (dm_snprintf(layer_name, len, MIRROR_SYNC_LAYER "_%d", i) < 0) {
		log_error("layer name allocation failed.");
		return 0;
	}

	if (!insert_layer_for_lv(cmd, lv, 0, layer_name)) {
		log_error("Failed to insert resync layer");
		return 0;
	}

	return 1;
}

static int _failed_mirrors_count(struct logical_volume *lv)
{
	struct lv_segment *lvseg;
	int ret = 0;
	unsigned s;

	dm_list_iterate_items(lvseg, &lv->segments) {
		if (!seg_is_mirrored(lvseg))
			return -1;
		for (s = 0; s < lvseg->area_count; s++) {
			if (seg_type(lvseg, s) == AREA_LV) {
				if (is_temporary_mirror_layer(seg_lv(lvseg, s)))
					ret += _failed_mirrors_count(seg_lv(lvseg, s));
				else if (seg_lv(lvseg, s)->status & PARTIAL_LV)
					++ ret;
				else if (seg_type(lvseg, s) == AREA_PV &&
					 is_missing_pv(seg_pv(lvseg, s)))
					++ret;
			}
		}
	}

	return ret;
}

static int _failed_logs_count(struct logical_volume *lv)
{
	int ret = 0;
	unsigned s;
	struct logical_volume *log_lv = first_seg(lv)->log_lv;
	if (log_lv && (log_lv->status & PARTIAL_LV)) {
		if (log_lv->status & MIRRORED)
			ret += _failed_mirrors_count(log_lv);
		else
			ret += 1;
	}
	for (s = 0; s < first_seg(lv)->area_count; s++) {
		if (seg_type(first_seg(lv), s) == AREA_LV &&
		    is_temporary_mirror_layer(seg_lv(first_seg(lv), s)))
			ret += _failed_logs_count(seg_lv(first_seg(lv), s));
	}
	return ret;
}


static struct dm_list *_failed_pv_list(struct volume_group *vg)
{
	struct dm_list *failed_pvs;
	struct pv_list *pvl, *new_pvl;

	if (!(failed_pvs = dm_pool_alloc(vg->vgmem, sizeof(*failed_pvs)))) {
		log_error("Allocation of list of failed_pvs failed.");
		return_NULL;
	}

	dm_list_init(failed_pvs);

	dm_list_iterate_items(pvl, &vg->pvs) {
		if (!is_missing_pv(pvl->pv))
			continue;

		/* 
		 * Finally, --repair will remove empty PVs.
		 * But we only want remove these which are output of repair,
		 * Do not count these which are already empty here.
		 * FIXME: code should traverse PV in LV not in whole VG.
		 * FIXME: layer violation? should it depend on vgreduce --removemising?
		 */
		if (pvl->pv->pe_alloc_count == 0)
			continue;

		if (!(new_pvl = dm_pool_alloc(vg->vgmem, sizeof(*new_pvl)))) {
			log_error("Allocation of failed_pvs list entry failed.");
			return_NULL;
		}
		new_pvl->pv = pvl->pv;
		dm_list_add(failed_pvs, &new_pvl->list);
	}

	return failed_pvs;
}

static int _is_partial_lv(struct logical_volume *lv,
			  void *baton __attribute__((unused)))
{
	return lv->status & PARTIAL_LV;
}

/*
 * Walk down the stacked mirror LV to the original mirror LV.
 */
static struct logical_volume *_original_lv(struct logical_volume *lv)
{
	struct logical_volume *next_lv = lv, *tmp_lv;

	while ((tmp_lv = find_temporary_mirror(next_lv)))
		next_lv = tmp_lv;

	return next_lv;
}

static void _lvconvert_mirrors_repair_ask(struct cmd_context *cmd,
					  int failed_log, int failed_mirrors,
					  int *replace_log, int *replace_mirrors)
{
	const char *leg_policy = NULL, *log_policy = NULL;

	int force = arg_count(cmd, force_ARG);
	int yes = arg_count(cmd, yes_ARG);

	*replace_log = *replace_mirrors = 1;

	if (arg_count(cmd, use_policies_ARG)) {
		leg_policy = find_config_tree_str(cmd, activation_mirror_image_fault_policy_CFG, NULL);
		log_policy = find_config_tree_str(cmd, activation_mirror_log_fault_policy_CFG, NULL);
		*replace_mirrors = strcmp(leg_policy, "remove");
		*replace_log = strcmp(log_policy, "remove");
		return;
	}

	if (force != PROMPT) {
		*replace_log = *replace_mirrors = 0;
		return;
	}

	if (yes)
		return;

	if (failed_log &&
	    yes_no_prompt("Attempt to replace failed mirror log? [y/n]: ") == 'n') {
		*replace_log = 0;
	}

	if (failed_mirrors &&
	    yes_no_prompt("Attempt to replace failed mirror images "
			  "(requires full device resync)? [y/n]: ") == 'n') {
		*replace_mirrors = 0;
	}
}

/*
 * _get_log_count
 * @lv: the mirror LV
 *
 * Get the number of on-disk copies of the log.
 *  0  = 'core'
 *  1  = 'disk'
 *  2+ = 'mirrored'
 */
static uint32_t _get_log_count(struct logical_volume *lv)
{
	struct logical_volume *log_lv;

	log_lv = first_seg(_original_lv(lv))->log_lv;
	if (log_lv)
		return lv_mirror_count(log_lv);

	return 0;
}

static int _lv_update_mirrored_log(struct logical_volume *lv,
				   struct dm_list *operable_pvs,
				   int log_count)
{
	int old_log_count;
	struct logical_volume *log_lv;

	/*
	 * When log_count is 0, mirrored log doesn't need to be
	 * updated here but it will be removed later.
	 */
	if (!log_count)
		return 1;

	log_lv = first_seg(_original_lv(lv))->log_lv;
	if (!log_lv || !(log_lv->status & MIRRORED))
		return 1;

	old_log_count = _get_log_count(lv);
	if (old_log_count == log_count)
		return 1;

	/* Reducing redundancy of the log */
	return remove_mirror_images(log_lv, log_count,
				    is_mirror_image_removable,
				    operable_pvs, 0U);
}

static int _lv_update_log_type(struct cmd_context *cmd,
			       struct lvconvert_params *lp,
			       struct logical_volume *lv,
			       struct dm_list *operable_pvs,
			       int log_count)
{
	int old_log_count;
	uint32_t region_size = (lp) ? lp->region_size :
		first_seg(lv)->region_size;
	alloc_policy_t alloc = (lp) ? lp->alloc : lv->alloc;
	struct logical_volume *original_lv;
	struct logical_volume *log_lv;

	old_log_count = _get_log_count(lv);
	if (old_log_count == log_count)
		return 1;

	original_lv = _original_lv(lv);
	/* Remove an existing log completely */
	if (!log_count) {
		if (!remove_mirror_log(cmd, original_lv, operable_pvs,
				       arg_count(cmd, yes_ARG) ||
				       arg_count(cmd, force_ARG)))
			return_0;
		return 1;
	}

	log_lv = first_seg(original_lv)->log_lv;

	/* Adding redundancy to the log */
	if (old_log_count < log_count) {
		region_size = adjusted_mirror_region_size(lv->vg->extent_size,
							  lv->le_count,
							  region_size);

		if (!add_mirror_log(cmd, original_lv, log_count,
				    region_size, operable_pvs, alloc))
			return_0;
		/*
		 * FIXME: This simple approach won't work in cluster mirrors,
		 *        but it doesn't matter because we don't support
		 *        mirrored logs in cluster mirrors.
		 */
		if (old_log_count &&
		    !_reload_lv(cmd, log_lv->vg, log_lv))
			return_0;

		return 1;
	}

	/* Reducing redundancy of the log */
	return remove_mirror_images(log_lv, log_count,
				    is_mirror_image_removable, operable_pvs, 1U);
}

/*
 * Reomove missing and empty PVs from VG, if are also in provided list
 */
static void _remove_missing_empty_pv(struct volume_group *vg, struct dm_list *remove_pvs)
{
	struct pv_list *pvl, *pvl_vg, *pvlt;
	int removed = 0;

	if (!remove_pvs)
		return;

	dm_list_iterate_items(pvl, remove_pvs) {
		dm_list_iterate_items_safe(pvl_vg, pvlt, &vg->pvs) {
			if (!id_equal(&pvl->pv->id, &pvl_vg->pv->id) ||
			    !is_missing_pv(pvl_vg->pv) ||
			    pvl_vg->pv->pe_alloc_count != 0)
				continue;

			/* FIXME: duplication of vgreduce code, move this to library */
			vg->free_count -= pvl_vg->pv->pe_count;
			vg->extent_count -= pvl_vg->pv->pe_count;
			del_pvl_from_vgs(vg, pvl_vg);
			free_pv_fid(pvl_vg->pv);

			removed++;
		}
	}

	if (removed) {
		if (!vg_write(vg) || !vg_commit(vg)) {
			stack;
			return;
		}
		log_warn("%d missing and now unallocated Physical Volumes removed from VG.", removed);
	}
}

/*
 * _lvconvert_mirrors_parse_params
 *
 * This function performs the following:
 *  1) Gets the old values of mimage and log counts
 *  2) Parses the CLI args to find the new desired values
 *  3) Adjusts 'lp->mirrors' to the appropriate absolute value.
 *     (Remember, 'lp->mirrors' is specified in terms of the number of "copies"
 *      vs. the number of mimages.  It can also be a relative value.)
 *  4) Sets 'lp->need_polling' if collapsing
 *  5) Validates other mirror params
 *
 * Returns: 1 on success, 0 on error
 */
static int _lvconvert_mirrors_parse_params(struct cmd_context *cmd,
					   struct logical_volume *lv,
					   struct lvconvert_params *lp,
					   uint32_t *old_mimage_count,
					   uint32_t *old_log_count,
					   uint32_t *new_mimage_count,
					   uint32_t *new_log_count)
{
	int repair = arg_count(cmd, repair_ARG);
	const char *mirrorlog;
	*old_mimage_count = lv_mirror_count(lv);
	*old_log_count = _get_log_count(lv);

	/*
	 * Collapsing a stack of mirrors:
	 *
	 * If called with no argument, try collapsing the resync layers
	 */
	if (!arg_count(cmd, mirrors_ARG) && !arg_count(cmd, mirrorlog_ARG) &&
	    !arg_count(cmd, corelog_ARG) && !arg_count(cmd, regionsize_ARG) &&
	    !arg_count(cmd, splitmirrors_ARG) && !repair) {
		*new_mimage_count = *old_mimage_count;
		*new_log_count = *old_log_count;

		if (find_temporary_mirror(lv) || (lv->status & CONVERTING))
			lp->need_polling = 1;
		return 1;
	}

	if ((arg_count(cmd, mirrors_ARG) && repair) ||
	    (arg_count(cmd, mirrorlog_ARG) && repair) ||
	    (arg_count(cmd, corelog_ARG) && repair)) {
		log_error("--repair cannot be used with --mirrors, --mirrorlog,"
			  " or --corelog");
		return 0;
	}

	if (arg_count(cmd, mirrorlog_ARG) && arg_count(cmd, corelog_ARG)) {
		log_error("--mirrorlog and --corelog are incompatible");
		return 0;
	}

	/*
	 * Adjusting mimage count?
	 */
	if (!arg_count(cmd, mirrors_ARG) && !arg_count(cmd, splitmirrors_ARG))
		lp->mirrors = *old_mimage_count;
	else if (lp->mirrors_sign == SIGN_PLUS)
		lp->mirrors = *old_mimage_count + lp->mirrors;
	else if (lp->mirrors_sign == SIGN_MINUS)
		lp->mirrors = (*old_mimage_count > lp->mirrors) ?
			*old_mimage_count - lp->mirrors: 0;
	else
		lp->mirrors += 1;

	*new_mimage_count = lp->mirrors;

	/* Too many mimages? */
	if (lp->mirrors > DEFAULT_MIRROR_MAX_IMAGES) {
		log_error("Only up to %d images in mirror supported currently.",
			  DEFAULT_MIRROR_MAX_IMAGES);
		return 0;
	}

	/* Did the user try to subtract more legs than available? */
	if (lp->mirrors < 1) {
		log_error("Unable to reduce images by specified amount - only %d in %s",
			  *old_mimage_count, lv->name);
		return 0;
	}

	/*
	 * FIXME: It would be nice to say what we are adjusting to, but
	 * I really don't know whether to specify the # of copies or mimages.
	 */
	if (*old_mimage_count != *new_mimage_count)
		log_verbose("Adjusting mirror image count of %s", lv->name);

	/*
	 * Adjust log type
	 *
	 * If we are converting from a mirror to another mirror or simply
	 * changing the log type, we start by assuming they want the log
	 * type the same and then parse the given args.  OTOH, If we are
	 * converting from linear to mirror, then we start from the default
	 * position that the user would like a 'disk' log.
	 */
	*new_log_count = (*old_mimage_count > 1) ? *old_log_count : 1;
	if (!arg_count(cmd, corelog_ARG) && !arg_count(cmd, mirrorlog_ARG))
		return 1;

	if (arg_count(cmd, corelog_ARG))
		*new_log_count = 0;

	mirrorlog = arg_str_value(cmd, mirrorlog_ARG,
				  !*new_log_count ? "core" : DEFAULT_MIRRORLOG);

	if (!strcmp("mirrored", mirrorlog))
		*new_log_count = 2;
	else if (!strcmp("disk", mirrorlog))
		*new_log_count = 1;
	else if (!strcmp("core", mirrorlog))
		*new_log_count = 0;
	else {
		log_error("Unknown mirrorlog type: %s", mirrorlog);
		return 0;
	}

	/*
	 * No mirrored logs for cluster mirrors until
	 * log daemon is multi-threaded.
	 */
	if ((*new_log_count == 2) && vg_is_clustered(lv->vg)) {
		log_error("Log type, \"mirrored\", is unavailable to cluster mirrors");
		return 0;
	}

	log_verbose("Setting logging type to %s", mirrorlog);

	/*
	 * Region size must not change on existing mirrors
	 */
	if (arg_count(cmd, regionsize_ARG) && (lv->status & MIRRORED) &&
	    (lp->region_size != first_seg(lv)->region_size)) {
		log_error("Mirror log region size cannot be changed on "
			  "an existing mirror.");
		return 0;
	}

	/*
	 * For the most part, we cannot handle multi-segment mirrors. Bail out
	 * early if we have encountered one.
	 */
	if ((lv->status & MIRRORED) && dm_list_size(&lv->segments) != 1) {
		log_error("Logical volume %s has multiple "
			  "mirror segments.", lv->name);
		return 0;
	}

	return 1;
}


/*
 * _lvconvert_mirrors_aux
 *
 * Add/remove mirror images and adjust log type.  'operable_pvs'
 * are the set of PVs open to removal or allocation - depending
 * on the operation being performed.
 */
static int _lvconvert_mirrors_aux(struct cmd_context *cmd,
				  struct logical_volume *lv,
				  struct lvconvert_params *lp,
				  struct dm_list *operable_pvs,
				  uint32_t new_mimage_count,
				  uint32_t new_log_count)
{
	uint32_t region_size;
	struct lv_segment *seg;
	struct logical_volume *layer_lv;
	uint32_t old_mimage_count = lv_mirror_count(lv);
	uint32_t old_log_count = _get_log_count(lv);

	if ((lp->mirrors == 1) && !(lv->status & MIRRORED)) {
		log_warn("Logical volume %s is already not mirrored.",
			 lv->name);
		return 1;
	}

	region_size = adjusted_mirror_region_size(lv->vg->extent_size,
						  lv->le_count,
						  lp->region_size);

	if (!operable_pvs)
		operable_pvs = lp->pvh;

	seg = first_seg(lv);

	/*
	 * Up-convert from linear to mirror
	 */
	if (!(lv->status & MIRRORED)) {
		/* FIXME Share code with lvcreate */

		/*
		 * FIXME should we give not only lp->pvh, but also all PVs
		 * currently taken by the mirror? Would make more sense from
		 * user perspective.
		 */
		if (!lv_add_mirrors(cmd, lv, new_mimage_count - 1, lp->stripes,
				    lp->stripe_size, region_size, new_log_count, operable_pvs,
				    lp->alloc, MIRROR_BY_LV))
			return_0;

		if (lp->wait_completion)
			lp->need_polling = 1;

		goto out;
	}

	/*
	 * Up-convert m-way mirror to n-way mirror
	 */
	if (new_mimage_count > old_mimage_count) {
		if (lv->status & LV_NOTSYNCED) {
			log_error("Can't add mirror to out-of-sync mirrored "
				  "LV: use lvchange --resync first.");
			return 0;
		}

		/*
		 * We allow snapshots of mirrors, but for now, we
		 * do not allow up converting mirrors that are under
		 * snapshots.  The layering logic is somewhat complex,
		 * and preliminary test show that the conversion can't
		 * seem to get the correct %'age of completion.
		 */
		if (lv_is_origin(lv)) {
			log_error("Can't add additional mirror images to "
				  "mirrors that are under snapshots");
			return 0;
		}

		/*
		 * Is there already a convert in progress?  We do not
		 * currently allow more than one.
		 */
		if (find_temporary_mirror(lv) || (lv->status & CONVERTING)) {
			log_error("%s is already being converted.  Unable to start another conversion.",
				  lv->name);
			return 0;
		}

		/*
		 * Log addition/removal should be done before the layer
		 * insertion to make the end result consistent with
		 * linear-to-mirror conversion.
		 */
		if (!_lv_update_log_type(cmd, lp, lv,
					 operable_pvs, new_log_count))
			return_0;

		/* Insert a temporary layer for syncing,
		 * only if the original lv is using disk log. */
		if (seg->log_lv && !_insert_lvconvert_layer(cmd, lv)) {
			log_error("Failed to insert resync layer");
			return 0;
		}

		/* FIXME: can't have multiple mlogs. force corelog. */
		if (!lv_add_mirrors(cmd, lv,
				    new_mimage_count - old_mimage_count,
				    lp->stripes, lp->stripe_size,
				    region_size, 0U, operable_pvs, lp->alloc,
				    MIRROR_BY_LV)) {
			layer_lv = seg_lv(first_seg(lv), 0);
			if (!remove_layer_from_lv(lv, layer_lv) ||
			    (lv_is_active(layer_lv) &&
			     !deactivate_lv(cmd, layer_lv)) ||
			    !lv_remove(layer_lv) || !vg_write(lv->vg) ||
			    !vg_commit(lv->vg)) {
				log_error("ABORTING: Failed to remove "
					  "temporary mirror layer %s.",
					  layer_lv->name);
				log_error("Manual cleanup with vgcfgrestore "
					  "and dmsetup may be required.");
				return 0;
			}

			return_0;
		}
		if (seg->log_lv)
			lv->status |= CONVERTING;
		lp->need_polling = 1;

		goto out_skip_log_convert;
	}

	/*
	 * Down-convert (reduce # of mimages).
	 */
	if (new_mimage_count < old_mimage_count) {
		uint32_t nmc = old_mimage_count - new_mimage_count;
		uint32_t nlc = (!new_log_count || lp->mirrors == 1) ? 1U : 0U;

		/* FIXME: Why did nlc used to be calculated that way? */

		/* Reduce number of mirrors */
		if (lp->keep_mimages) {
			if (arg_count(cmd, trackchanges_ARG)) {
				log_error("--trackchanges is not available "
					  "to 'mirror' segment type");
				return 0;
			}
			if (!lv_split_mirror_images(lv, lp->lv_split_name,
						    nmc, operable_pvs))
				return 0;
		} else if (!lv_remove_mirrors(cmd, lv, nmc, nlc,
					      is_mirror_image_removable, operable_pvs, 0))
			return_0;

		goto out; /* Just in case someone puts code between */
	}

out:
	/*
	 * Converting the log type
	 */
	if ((lv->status & MIRRORED) && (old_log_count != new_log_count)) {
		if (!_lv_update_log_type(cmd, lp, lv,
					 operable_pvs, new_log_count))
			return_0;
	}

out_skip_log_convert:

	if (!_reload_lv(cmd, lv->vg, lv))
		return_0;

	return 1;
}

int mirror_remove_missing(struct cmd_context *cmd,
			  struct logical_volume *lv, int force)
{
	struct dm_list *failed_pvs;
	int log_count = _get_log_count(lv) - _failed_logs_count(lv);

	if (!(failed_pvs = _failed_pv_list(lv->vg)))
		return_0;

	if (force && _failed_mirrors_count(lv) == (int)lv_mirror_count(lv)) {
		log_error("No usable images left in %s.", lv->name);
		return lv_remove_with_dependencies(cmd, lv, DONT_PROMPT, 0);
        }

	/*
	 * We must adjust the log first, or the entire mirror
	 * will get stuck during a suspend.
	 */
	if (!_lv_update_mirrored_log(lv, failed_pvs, log_count))
		return 0;

	if (_failed_mirrors_count(lv) > 0 &&
	    !lv_remove_mirrors(cmd, lv, _failed_mirrors_count(lv),
			       log_count ? 0U : 1U,
			       _is_partial_lv, NULL, 0))
		return 0;

	if (lv_is_mirrored(lv) &&
	    !_lv_update_log_type(cmd, NULL, lv, failed_pvs, log_count))
		return 0;

	if (!_reload_lv(cmd, lv->vg, lv))
		return_0;

	return 1;
}

/*
 * _lvconvert_mirrors_repair
 *
 * This function operates in two phases.  First, all of the bad
 * devices are removed from the mirror.  Then, if desired by the
 * user, the devices are replaced.
 *
 * 'old_mimage_count' and 'old_log_count' are there so we know
 * what to convert to after the removal of devices.
 */
static int _lvconvert_mirrors_repair(struct cmd_context *cmd,
				     struct logical_volume *lv,
				     struct lvconvert_params *lp)
{
	int failed_logs = 0;
	int failed_mimages = 0;
	int replace_logs = 0;
	int replace_mimages = 0;
	uint32_t log_count;

	uint32_t original_mimages = lv_mirror_count(lv);
	uint32_t original_logs = _get_log_count(lv);

	cmd->handles_missing_pvs = 1;
	cmd->partial_activation = 1;
	lp->need_polling = 0;

	lv_check_transient(lv); /* TODO check this in lib for all commands? */

	if (!(lv->status & PARTIAL_LV)) {
		log_warn("%s is consistent. Nothing to repair.", lv->name);
		return 1;
	}

	failed_mimages = _failed_mirrors_count(lv);
	failed_logs = _failed_logs_count(lv);

	mirror_remove_missing(cmd, lv, 0);

	if (failed_mimages)
		log_error("Mirror status: %d of %d images failed.",
			  failed_mimages, original_mimages);

	/*
	 * Count the failed log devices
	 */
	if (failed_logs)
		log_error("Mirror log status: %d of %d images failed.",
			  failed_logs, original_logs);

	/*
	 * Find out our policies
	 */
	_lvconvert_mirrors_repair_ask(cmd, failed_logs, failed_mimages,
				      &replace_logs, &replace_mimages);

	/*
	 * Second phase - replace faulty devices
	 */
	lp->mirrors = replace_mimages ? original_mimages : (original_mimages - failed_mimages);

	/*
	 * It does not make sense to replace the log if the volume is no longer
	 * a mirror.
	 */
	if (lp->mirrors == 1)
		replace_logs = 0;

	log_count = replace_logs ? original_logs : (original_logs - failed_logs);

	while (replace_mimages || replace_logs) {
		log_warn("Trying to up-convert to %d images, %d logs.", lp->mirrors, log_count);
		if (_lvconvert_mirrors_aux(cmd, lv, lp, NULL,
					   lp->mirrors, log_count))
			break;
		else {
			if (lp->mirrors > 2)
				-- lp->mirrors;
			else if (log_count > 0)
				-- log_count;
			else
				break; /* nowhere to go, anymore... */
		}
	}

	if (replace_mimages && lv_mirror_count(lv) != original_mimages)
		log_warn("WARNING: Failed to replace %d of %d images in volume %s",
			 original_mimages - lv_mirror_count(lv), original_mimages, lv->name);
	if (replace_logs && _get_log_count(lv) != original_logs)
		log_warn("WARNING: Failed to replace %d of %d logs in volume %s",
			 original_logs - _get_log_count(lv), original_logs, lv->name);

	/* if (!arg_count(cmd, use_policies_ARG) && (lp->mirrors != old_mimage_count
						  || log_count != old_log_count))
						  return 0; */

	return 1;
}

static int _lvconvert_validate_thin(struct logical_volume *lv,
				    struct lvconvert_params *lp)
{
	if (!lv_is_thin_pool(lv) && !lv_is_thin_volume(lv))
		return 1;

	log_error("Converting thin%s segment type for \"%s/%s\" to %s is not supported.",
		  lv_is_thin_pool(lv) ? " pool" : "",
		  lv->vg->name, lv->name, lp->segtype->name);

	if (lv_is_thin_volume(lv))
		return 0;

	/* Give advice for thin pool conversion */
	log_error("For pool data volume conversion use \"%s/%s\".",
		  lv->vg->name, seg_lv(first_seg(lv), 0)->name);
	log_error("For pool metadata volume conversion use \"%s/%s\".",
		  lv->vg->name, first_seg(lv)->metadata_lv->name);
	return 0;
}

/*
 * _lvconvert_mirrors
 *
 * Determine what is being done.  Are we doing a conversion, repair, or
 * collapsing a stack?  Once determined, call helper functions.
 */
static int _lvconvert_mirrors(struct cmd_context *cmd,
			      struct logical_volume *lv,
			      struct lvconvert_params *lp)
{
	int repair = arg_count(cmd, repair_ARG);
	uint32_t old_mimage_count;
	uint32_t old_log_count;
	uint32_t new_mimage_count;
	uint32_t new_log_count;

	if (lp->merge_mirror) {
		log_error("Unable to merge mirror images"
			  "of segment type 'mirror'");
		return 0;
	}

	if (!_lvconvert_validate_thin(lv, lp))
		return_0;

	if (lv_is_thin_type(lv)) {
		log_error("Mirror segment type cannot be used for thinpool%s.\n"
			  "Try \"raid1\" segment type instead.",
			  lv_is_thin_pool_data(lv) ? "s" : " metadata");
		return 0;
	}

	/* Adjust mimage and/or log count */
	if (!_lvconvert_mirrors_parse_params(cmd, lv, lp,
					     &old_mimage_count, &old_log_count,
					     &new_mimage_count, &new_log_count))
		return 0;

        if (((old_mimage_count < new_mimage_count && old_log_count > new_log_count) ||
             (old_mimage_count > new_mimage_count && old_log_count < new_log_count)) &&
            lp->pv_count) {
		log_error("Cannot both allocate and free extents when "
			  "specifying physical volumes to use.");
		log_error("Please specify the operation in two steps.");
		return 0;
        }

	/* Nothing to do?  (Probably finishing collapse.) */
	if ((old_mimage_count == new_mimage_count) &&
	    (old_log_count == new_log_count) && !repair)
		return 1;

	if (repair)
		return _lvconvert_mirrors_repair(cmd, lv, lp);

	if (!_lvconvert_mirrors_aux(cmd, lv, lp, NULL,
				    new_mimage_count, new_log_count))
		return 0;

	if (!lp->need_polling)
		log_print_unless_silent("Logical volume %s converted.", lv->name);

	backup(lv->vg);
	return 1;
}

static int _is_valid_raid_conversion(const struct segment_type *from_segtype,
				    const struct segment_type *to_segtype)
{
	if (from_segtype == to_segtype)
		return 1;

	if (!segtype_is_raid(from_segtype) && !segtype_is_raid(to_segtype))
		return_0;  /* Not converting to or from RAID? */

	return 1;
}

static void _lvconvert_raid_repair_ask(struct cmd_context *cmd, int *replace_dev)
{
	const char *dev_policy = NULL;

	int force = arg_count(cmd, force_ARG);
	int yes = arg_count(cmd, yes_ARG);

	*replace_dev = 1;

	if (arg_count(cmd, use_policies_ARG)) {
		dev_policy = find_config_tree_str(cmd, activation_raid_fault_policy_CFG, NULL);

		if (!strcmp(dev_policy, "allocate") ||
		    !strcmp(dev_policy, "replace"))
			return;

		/* else if (!strcmp(dev_policy, "anything_else")) -- no replace */
		*replace_dev = 0;
		return;
	}

	if (force != PROMPT) {
		*replace_dev = 0;
		return;
	}

	if (yes)
		return;

	if (yes_no_prompt("Attempt to replace failed RAID images "
			  "(requires full device resync)? [y/n]: ") == 'n') {
		*replace_dev = 0;
	}
}

static int _lvconvert_raid(struct logical_volume *lv, struct lvconvert_params *lp)
{
	int replace = 0, image_count = 0;
	struct dm_list *failed_pvs;
	struct cmd_context *cmd = lv->vg->cmd;
	struct lv_segment *seg = first_seg(lv);
	percent_t sync_percent;

	if (!arg_count(cmd, type_ARG))
		lp->segtype = seg->segtype;

	/* Can only change image count for raid1 and linear */
	if (arg_count(cmd, mirrors_ARG) &&
	    !seg_is_mirrored(seg) && !seg_is_linear(seg)) {
		log_error("'--mirrors/-m' is not compatible with %s",
			  seg->segtype->ops->name(seg));
		return 0;
	}

	if (!_lvconvert_validate_thin(lv, lp))
		return_0;

	if (!_is_valid_raid_conversion(seg->segtype, lp->segtype)) {
		log_error("Unable to convert %s/%s from %s to %s",
			  lv->vg->name, lv->name,
			  seg->segtype->ops->name(seg), lp->segtype->name);
		return 0;
	}

	/* Change number of RAID1 images */
	if (arg_count(cmd, mirrors_ARG) || arg_count(cmd, splitmirrors_ARG)) {
		image_count = lv_raid_image_count(lv);
		if (lp->mirrors_sign == SIGN_PLUS)
			image_count += lp->mirrors;
		else if (lp->mirrors_sign == SIGN_MINUS)
			image_count -= lp->mirrors;
		else
			image_count = lp->mirrors + 1;

		if (image_count < 1) {
			log_error("Unable to %s images by specified amount",
				  arg_count(cmd, splitmirrors_ARG) ?
				  "split" : "reduce");
			return 0;
		}
	}

	if (lp->merge_mirror)
		return lv_raid_merge(lv);

	if (arg_count(cmd, trackchanges_ARG))
		return lv_raid_split_and_track(lv, lp->pvh);

	if (arg_count(cmd, splitmirrors_ARG))
		return lv_raid_split(lv, lp->lv_split_name,
				     image_count, lp->pvh);

	if (arg_count(cmd, mirrors_ARG))
		return lv_raid_change_image_count(lv, image_count, lp->pvh);

	if (arg_count(cmd, type_ARG))
		return lv_raid_reshape(lv, lp->segtype);

	if (arg_count(cmd, replace_ARG))
		return lv_raid_replace(lv, lp->replace_pvh, lp->pvh);

	if (arg_count(cmd, repair_ARG)) {
		if (!lv_is_active_exclusive_locally(lv)) {
			log_error("%s/%s must be active %sto perform this"
				  " operation.", lv->vg->name, lv->name,
				  vg_is_clustered(lv->vg) ?
				  "exclusive locally " : "");
			return 0;
		}

		if (!lv_raid_percent(lv, &sync_percent)) {
			log_error("Unable to determine sync status of %s/%s.",
				  lv->vg->name, lv->name);
			return 0;
		}

		if (sync_percent != PERCENT_100) {
			log_error("WARNING: %s/%s is not in-sync.",
				  lv->vg->name, lv->name);
			log_error("WARNING: Portions of the array may"
				  " be unrecoverable.");

			/*
			 * The kernel will not allow a device to be replaced
			 * in an array that is not in-sync unless we override
			 * by forcing the array to be considered "in-sync".
			 */
			init_mirror_in_sync(1);
		}

		_lvconvert_raid_repair_ask(cmd, &replace);

		if (replace) {
			if (!(failed_pvs = _failed_pv_list(lv->vg)))
				return_0;

			if (!lv_raid_replace(lv, failed_pvs, lp->pvh)) {
				log_error("Failed to replace faulty devices in"
					  " %s/%s.", lv->vg->name, lv->name);
				return 0;
			}

			log_print_unless_silent("Faulty devices in %s/%s successfully"
						" replaced.", lv->vg->name, lv->name);
			return 1;
		}

		/* "warn" if policy not set to replace */
		if (arg_count(cmd, use_policies_ARG))
			log_warn("Use 'lvconvert --repair %s/%s' to replace "
				 "failed device.", lv->vg->name, lv->name);
		return 1;
	}

	log_error("Conversion operation not yet supported.");
	return 0;
}

static int _lvconvert_splitsnapshot(struct cmd_context *cmd, struct logical_volume *cow,
				    struct lvconvert_params *lp)
{
	struct lvinfo info;
	struct volume_group *vg = cow->vg;

	if (!lv_is_cow(cow)) {
		log_error("%s/%s is not a snapshot.", vg->name, cow->name);
		return ECMD_FAILED;
	}

	if (lv_is_origin(cow) || lv_is_external_origin(cow)) {
		log_error("Unable to split LV %s/%s that is a snapshot origin.", vg->name, cow->name);
		return ECMD_FAILED;
	}

	if (lv_is_merging_cow(cow)) {
		log_error("Unable to split off snapshot %s/%s being merged into its origin.", vg->name, cow->name);
		return ECMD_FAILED;
	}

	if (lv_is_virtual_origin(origin_from_cow(cow))) {
		log_error("Unable to split off snapshot %s/%s with virtual origin.", vg->name, cow->name);
		return ECMD_FAILED;
	}

	if (lv_is_thin_pool(cow) || lv_is_pool_metadata_spare(cow)) {
		log_error("Unable to split off LV %s/%s needed by thin volume(s).", vg->name, cow->name);
		return ECMD_FAILED;
	}

	if (!(vg->fid->fmt->features & FMT_MDAS)) {
		log_error("Unable to split off snapshot %s/%s using old LVM1-style metadata.", vg->name, cow->name);
		return ECMD_FAILED;
	}

	if (!vg_check_status(vg, LVM_WRITE))
		return_ECMD_FAILED;

	if (lv_is_mirror_type(cow) || lv_is_raid_type(cow) || lv_is_thin_type(cow)) {
		log_error("LV %s/%s type is unsupported with --splitsnapshot.", vg->name, cow->name);
		return ECMD_FAILED;
	}

        if (lv_info(cmd, cow, 0, &info, 1, 0)) {
                if (!lv_check_not_in_use(cmd, cow, &info))
                        return_0;

                if ((lp->force == PROMPT) &&
                    lv_is_visible(cow) &&
                    lv_is_active(cow)) {
                        if (yes_no_prompt("Do you really want to split off active "
                                          "logical volume %s? [y/n]: ", cow->name) == 'n') {
                                log_error("Logical volume %s not split.", cow->name);
                                return ECMD_FAILED;
                        }
                }
        }

	if (!archive(vg))
		return_ECMD_FAILED;

	log_verbose("Splitting snapshot %s/%s from its origin.", vg->name, cow->name);

	if (!vg_remove_snapshot(cow))
		return_ECMD_FAILED;

	backup(vg);

	log_print_unless_silent("Logical Volume %s/%s split from its origin.", vg->name, cow->name);

	return ECMD_PROCESSED;
}

static int _lvconvert_snapshot(struct cmd_context *cmd,
			       struct logical_volume *lv,
			       struct lvconvert_params *lp)
{
	struct logical_volume *org;

	if (lv->status & MIRRORED) {
		log_error("Unable to convert mirrored LV \"%s\" into a snapshot.", lv->name);
		return 0;
	}

	if (lv_is_origin(lv)) {
		/* Unsupported stack */
		log_error("Unable to convert origin \"%s\" into a snapshot.", lv->name);
		return 0;
	}

	if (!(org = find_lv(lv->vg, lp->origin))) {
		log_error("Couldn't find origin volume '%s'.", lp->origin);
		return 0;
	}

	if (org == lv) {
		log_error("Unable to use \"%s\" as both snapshot and origin.",
			  lv->name);
		return 0;
	}

	if (!cow_has_min_chunks(lv->vg, lv->le_count, lp->chunk_size))
		return_0;

	if (org->status & (LOCKED|PVMOVE|MIRRORED) || lv_is_cow(org)) {
		log_error("Unable to convert an LV into a snapshot of a %s LV.",
			  org->status & LOCKED ? "locked" :
			  org->status & PVMOVE ? "pvmove" :
			  org->status & MIRRORED ? "mirrored" :
			  "snapshot");
		return 0;
	}

	if (!lp->zero || !(lv->status & LVM_WRITE))
		log_warn("WARNING: \"%s\" not zeroed", lv->name);
	else if (!wipe_lv(lv, (struct wipe_params) { .do_zero = 1 })) {
		log_error("Aborting. Failed to wipe snapshot "
			  "exception store.");
		return 0;
	}

	if (!deactivate_lv(cmd, lv)) {
		log_error("Couldn't deactivate LV %s.", lv->name);
		return 0;
	}

	if (!archive(lv->vg))
		return_0;

	if (!vg_add_snapshot(org, lv, NULL, org->le_count, lp->chunk_size)) {
		log_error("Couldn't create snapshot.");
		return 0;
	}

	/* store vg on disk(s) */
	if (!_reload_lv(cmd, lv->vg, org))
		return_0;

	log_print_unless_silent("Logical volume %s converted to snapshot.", lv->name);

	return 1;
}

static int _lvconvert_merge_old_snapshot(struct cmd_context *cmd,
					 struct logical_volume *lv,
					 struct lvconvert_params *lp)
{
	int r = 0;
	int merge_on_activate = 0;
	struct logical_volume *origin = origin_from_cow(lv);
	struct lv_segment *snap_seg = find_snapshot(lv);
	struct lvinfo info;
	percent_t snap_percent;

	/* Check if merge is possible */
	if (!lv_is_cow(lv)) {
		log_error("\"%s\" is not a mergeable logical volume.",
			  lv->name);
		return 0;
	}

	if (lv_is_merging_cow(lv)) {
		log_error("Snapshot %s is already merging.", lv->name);
		return 0;
	}

	if (lv_is_merging_origin(origin)) {
		log_error("Snapshot %s is already merging into the origin.",
			  find_snapshot(origin)->cow->name);
		return 0;
	}

	if (lv_is_virtual_origin(origin)) {
		log_error("Snapshot %s has virtual origin.", lv->name);
		return 0;
	}

	if (lv_is_external_origin(origin_from_cow(lv))) {
		log_error("Cannot merge snapshot \"%s\" into "
			  "the read-only external origin \"%s\".",
			  lv->name, origin_from_cow(lv)->name);
		return 0;
	}

	if (lv_info(lv->vg->cmd, lv, 0, &info, 1, 0)
	    && info.exists && info.live_table &&
	    (!lv_snapshot_percent(lv, &snap_percent) ||
	     snap_percent == PERCENT_INVALID)) {
		log_error("Unable to merge invalidated snapshot LV \"%s\".",
			  lv->name);
		return 0;
	}

	if (!archive(lv->vg))
		return_0;

	/*
	 * Prevent merge with open device(s) as it would likely lead
	 * to application/filesystem failure.  Merge on origin's next
	 * activation if either the origin or snapshot LV are currently
	 * open.
	 *
	 * FIXME testing open_count is racey; snapshot-merge target's
	 * constructor and DM should prevent appropriate devices from
	 * being open.
	 */
	if (lv_info(cmd, origin, 0, &info, 1, 0) &&
	    !lv_check_not_in_use(cmd, origin, &info)) {
		log_print_unless_silent("Can't merge over open origin volume.");
		merge_on_activate = 1;
	} else if (lv_info(cmd, lv, 0, &info, 1, 0) &&
		   !lv_check_not_in_use(cmd, lv, &info)) {
		log_print_unless_silent("Can't merge when snapshot is open.");
		merge_on_activate = 1;
	}

	init_snapshot_merge(snap_seg, origin);

	if (snap_seg->segtype->ops->target_present &&
	    !snap_seg->segtype->ops->target_present(snap_seg->lv->vg->cmd,
						    snap_seg, NULL)) {
		log_error("Can't initialize snapshot merge. "
			  "Missing support in kernel?");
		return 0;
	}

	/* store vg on disk(s) */
	if (!vg_write(lv->vg))
		return_0;

	if (merge_on_activate) {
		/* commit vg but skip starting the merge */
		if (!vg_commit(lv->vg))
			return_0;
		r = 1;
		log_print_unless_silent("Merging of snapshot %s will start "
					"next activation.", lv->name);
		goto out;
	}

	/* Perform merge */
	if (!suspend_lv(cmd, origin)) {
		log_error("Failed to suspend origin %s.", origin->name);
		vg_revert(lv->vg);
		goto out;
	}

	if (!vg_commit(lv->vg)) {
		if (!resume_lv(cmd, origin))
			stack;
		goto_out;
	}

	if (!resume_lv(cmd, origin)) {
		log_error("Failed to reactivate origin %s.", origin->name);
		goto out;
	}

	lp->need_polling = 1;
	lp->lv_to_poll = origin;

	r = 1;
	log_print_unless_silent("Merging of volume %s started.", lv->name);
out:
	backup(lv->vg);

	return r;
}

static int _lvconvert_merge_thin_snapshot(struct cmd_context *cmd,
					  struct logical_volume *lv,
					  struct lvconvert_params *lp)
{
	int origin_is_active = 0, r = 0;
	struct lv_segment *snap_seg = first_seg(lv);
	struct logical_volume *origin = snap_seg->origin;

	if (!origin) {
		log_error("\"%s\" is not a mergeable logical volume.",
			  lv->name);
		return 0;
	}

	/* Check if merge is possible */
	if (lv_is_merging_origin(origin)) {
		log_error("Snapshot %s is already merging into the origin.",
			  find_snapshot(origin)->lv->name);
		return 0;
	}

	if (lv_is_external_origin(origin)) {
		log_error("\"%s\" is read-only external origin \"%s\".",
			  lv->name, origin_from_cow(lv)->name);
		return 0;
	}

	if (lv_is_origin(origin)) {
		log_error("Merging into the old snapshot origin %s is not supported.",
			  origin->name);
		return 0;
	}

	if (!archive(lv->vg))
		return_0;

	// FIXME: allow origin to be specified
	// FIXME: verify snapshot is descendant of specified origin

	/*
	 * Prevent merge with open device(s) as it would likely lead
	 * to application/filesystem failure.  Merge on origin's next
	 * activation if either the origin or snapshot LV can't be
	 * deactivated.
	 */
	if (!deactivate_lv(cmd, lv))
		log_print_unless_silent("Delaying merge since snapshot is open.");
	else if ((origin_is_active = lv_is_active(origin)) &&
		 !deactivate_lv(cmd, origin))
		log_print_unless_silent("Delaying merge since origin volume is open.");
	else {
		/*
		 * Both thin snapshot and origin are inactive,
		 * replace the origin LV with its snapshot LV.
		 */
		if (!_finish_thin_merge(cmd, origin, lv))
			goto_out;

		if (origin_is_active && !activate_lv(cmd, lv)) {
			log_error("Failed to reactivate origin %s.", lv->name);
			goto out;
		}

		r = 1;
		goto out;
	}

	init_snapshot_merge(snap_seg, origin);

	/* Commit vg, merge will start with next activation */
	if (!vg_write(lv->vg) || !vg_commit(lv->vg))
		return_0;

	log_print_unless_silent("Merging of thin snapshot %s will occur on "
				"next activation.", lv->name);
	r = 1;
out:
	backup(lv->vg);

	return r;
}

static int _lvconvert_thinpool_repair(struct cmd_context *cmd,
				      struct logical_volume *pool_lv,
				      struct lvconvert_params *lp)
{
	const char *dmdir = dm_dir();
	const char *thin_dump =
		find_config_tree_str_allow_empty(cmd, global_thin_dump_executable_CFG, NULL);
	const char *thin_repair =
		find_config_tree_str_allow_empty(cmd, global_thin_repair_executable_CFG, NULL);
	const struct dm_config_node *cn;
	const struct dm_config_value *cv;
	int ret = 0, status;
	int args = 0;
	const char *argv[19]; /* Max supported 10 args */
	char *split, *dm_name, *trans_id_str;
	char meta_path[PATH_MAX];
	char pms_path[PATH_MAX];
	uint64_t trans_id;
	struct logical_volume *pmslv;
	struct logical_volume *mlv = first_seg(pool_lv)->metadata_lv;
	struct pipe_data pdata;
	FILE *f;

	if (!thin_repair[0]) {
		log_error("Thin repair commnand is not configured. Repair is disabled.");
		return 0; /* Checking disabled */
	}

	pmslv = pool_lv->vg->pool_metadata_spare_lv;

	/* Check we have pool metadata spare LV */
	if (!handle_pool_metadata_spare(pool_lv->vg, 0, NULL, 1))
		return_0;

	if (pmslv != pool_lv->vg->pool_metadata_spare_lv) {
		if (!vg_write(pool_lv->vg) || !vg_commit(pool_lv->vg))
			return_0;
		pmslv = pool_lv->vg->pool_metadata_spare_lv;
	}

	if (!(dm_name = dm_build_dm_name(cmd->mem, mlv->vg->name,
					 mlv->name, NULL)) ||
	    (dm_snprintf(meta_path, sizeof(meta_path), "%s/%s", dmdir, dm_name) < 0)) {
		log_error("Failed to build thin metadata path.");
		return 0;
	}

	if (!(dm_name = dm_build_dm_name(cmd->mem, pmslv->vg->name,
					 pmslv->name, NULL)) ||
	    (dm_snprintf(pms_path, sizeof(pms_path), "%s/%s", dmdir, dm_name) < 0)) {
		log_error("Failed to build pool metadata spare path.");
		return 0;
	}

	if ((cn = find_config_tree_node(cmd, global_thin_repair_options_CFG, NULL))) {
		for (cv = cn->v; cv && args < 16; cv = cv->next) {
			if (cv->type != DM_CFG_STRING) {
				log_error("Invalid string in config file: "
					  "global/thin_repair_options");
				return 0;
			}
			argv[++args] = cv->v.str;
		}
	} else {
		/* Use default options (no support for options with spaces) */
		if (!(split = dm_pool_strdup(cmd->mem, DEFAULT_THIN_REPAIR_OPTIONS))) {
			log_error("Failed to duplicate thin repair string.");
			return 0;
		}
		args = dm_split_words(split, 16, 0, (char**) argv + 1);
	}

	if (args == 10) {
		log_error("Too many options for thin repair command.");
		return 0;
	}

	argv[0] = thin_repair;
	argv[++args] = "-i";
	argv[++args] = meta_path;
	argv[++args] = "-o";
	argv[++args] = pms_path;
	argv[++args] = NULL;

	if (pool_is_active(pool_lv)) {
		log_error("Only inactive pool can be repaired.");
		return 0;
	}

	if (!activate_lv_local(cmd, pmslv)) {
		log_error("Cannot activate pool metadata spare volume %s.",
			  pmslv->name);
		return 0;
	}

	if (!activate_lv_local(cmd, mlv)) {
		log_error("Cannot activate thin pool metadata volume %s.",
			  mlv->name);
		goto deactivate_pmslv;
	}

	if (!(ret = exec_cmd(cmd, (const char * const *)argv, &status, 1))) {
		log_error("Repair of thin metadata volume of thin pool %s/%s failed (status:%d). "
			  "Manual repair required!",
			  pool_lv->vg->name, pool_lv->name, status);
		goto deactivate_mlv;
	}

	if (thin_dump[0]) {
		argv[0] = thin_dump;
		argv[1] = pms_path;
		argv[2] = NULL;

		if (!(f = pipe_open(cmd, argv, 0, &pdata)))
			log_warn("WARNING: Cannot read output from %s %s.", thin_dump, pms_path);
		else {
			/*
			 * Scan only the 1st. line for transation id.
			 * Watch out, if the thin_dump format changes
			 */
			if ((fgets(meta_path, sizeof(meta_path), f) > 0) &&
			    (trans_id_str = strstr(meta_path, "transaction=\"")) &&
			    (sscanf(trans_id_str + 13, "%" PRIu64, &trans_id) == 1) &&
			    (trans_id != first_seg(pool_lv)->transaction_id) &&
			    ((trans_id - 1) != first_seg(pool_lv)->transaction_id))
				log_error("Transaction id %" PRIu64 " from pool \"%s/%s\" "
					  "does not match repaired transaction id "
					  "%" PRIu64 " from %s.",
					  first_seg(pool_lv)->transaction_id,
					  pool_lv->vg->name, pool_lv->name, trans_id,
					  pms_path);

			(void) pipe_close(&pdata); /* killing pipe */
		}
	}

deactivate_mlv:
	if (!deactivate_lv(cmd, mlv)) {
		log_error("Cannot deactivate thin pool metadata volume %s.",
			  mlv->name);
		return 0;
	}

deactivate_pmslv:
	if (!deactivate_lv(cmd, pmslv)) {
		log_error("Cannot deactivate thin pool metadata volume %s.",
			  mlv->name);
		return 0;
	}

	if (!ret)
		return 0;

	if (pmslv == pool_lv->vg->pool_metadata_spare_lv) {
		pool_lv->vg->pool_metadata_spare_lv = NULL;
		pmslv->status &= ~POOL_METADATA_SPARE;
		lv_set_visible(pmslv);
	}

	/* Try to allocate new pool metadata spare LV */
	if (!handle_pool_metadata_spare(pool_lv->vg, 0, NULL, 1))
		stack;

	if (dm_snprintf(meta_path, sizeof(meta_path), "%s%%d", mlv->name) < 0) {
		log_error("Can't prepare new name for %s.", mlv->name);
		return 0;
	}

	if (!generate_lv_name(pool_lv->vg, meta_path, pms_path, sizeof(pms_path))) {
		log_error("Can't generate new name for %s.", meta_path);
		return 0;
	}

	if (!detach_pool_metadata_lv(first_seg(pool_lv), &mlv))
		return_0;

	if (!_swap_lv_identifiers(cmd, mlv, pmslv))
		return_0;

	/* Used _pmspare will become _tmeta */
	if (!attach_pool_metadata_lv(first_seg(pool_lv), pmslv))
		return_0;

	/* Used _tmeta will become visible  _tmeta%d */
	if (!lv_rename_update(cmd, mlv, pms_path, 0))
		return_0;

	if (!vg_write(pool_lv->vg) || !vg_commit(pool_lv->vg))
		return_0;

	log_warn("WARNING: If everything works, remove \"%s/%s\".",
		 mlv->vg->name, mlv->name);

	log_warn("WARNING: Use pvmove command to move \"%s/%s\" on the best fitting PV.",
		 mlv->vg->name, first_seg(pool_lv)->metadata_lv->name);

	return 1;
}

static int _lvconvert_thinpool_external(struct cmd_context *cmd,
					struct logical_volume *pool_lv,
					struct logical_volume *external_lv,
					struct lvconvert_params *lp)
{
	struct logical_volume *torigin_lv;
	struct volume_group *vg = pool_lv->vg;
	struct lvcreate_params lvc = {
		.activate = CHANGE_AE,
		.alloc = ALLOC_INHERIT,
		.lv_name = lp->origin_lv_name,
		.major = -1,
		.minor = -1,
		.permission = LVM_READ,
		.pool = pool_lv->name,
		.pvh = &vg->pvs,
		.read_ahead = DM_READ_AHEAD_AUTO,
		.stripes = 1,
		.vg_name = vg->name,
		.voriginextents = external_lv->le_count,
		.voriginsize = external_lv->size,
	};

	dm_list_init(&lvc.tags);

	if (!pool_supports_external_origin(first_seg(pool_lv), external_lv))
		return_0;

	if (!(lvc.segtype = get_segtype_from_string(cmd, "thin")))
		return_0;

	/* New thin LV needs to be created (all messages sent to pool) */
	if (!(torigin_lv = lv_create_single(vg, &lvc)))
		return_0;

	/* Deactivate prepared Thin LV */
	if (!deactivate_lv(cmd, torigin_lv)) {
		log_error("Aborting. Unable to deactivate new LV. "
			  "Manual intervention required.");
		return 0;
	}

	/*
	 * Crashing till this point will leave plain thin volume
	 * which could be easily removed by the user after i.e. power-off
	 */

	if (!_swap_lv_identifiers(cmd, torigin_lv, external_lv)) {
		stack;
		goto revert_new_lv;
	}

	/* Preserve read-write status of original LV here */
	torigin_lv->status |= (external_lv->status & LVM_WRITE);

	if (!attach_thin_external_origin(first_seg(torigin_lv), external_lv)) {
		stack;
		goto revert_new_lv;
	}

	if (!_reload_lv(cmd, vg, torigin_lv)) {
		stack;
		goto deactivate_and_revert_new_lv;
	}

	log_print_unless_silent("Converted %s/%s to thin external origin.",
				vg->name, external_lv->name);

	return 1;

deactivate_and_revert_new_lv:
	if (!_swap_lv_identifiers(cmd, torigin_lv, external_lv))
		stack;

	if (!deactivate_lv(cmd, torigin_lv)) {
		log_error("Unable to deactivate failed new LV. "
			  "Manual intervention required.");
		return 0;
	}

	if (!detach_thin_external_origin(first_seg(torigin_lv)))
		return_0;

revert_new_lv:
	/* FIXME Better to revert to backup of metadata? */
	if (!lv_remove(torigin_lv) || !vg_write(vg) || !vg_commit(vg))
		log_error("Manual intervention may be required to remove "
			  "abandoned LV(s) before retrying.");
	else
		backup(vg);

	return 0;
}

static int _lvconvert_update_pool_params(struct logical_volume *pool_lv,
					 struct lvconvert_params *lp)
{
	if (seg_is_cache_pool(lp))
		return update_cache_pool_params(pool_lv->vg, lp->target_attr,
						lp->passed_args,
						pool_lv->le_count,
						pool_lv->vg->extent_size,
						&lp->thin_chunk_size_calc_policy,
						&lp->chunk_size,
						&lp->discards,
						&lp->poolmetadata_size,
						&lp->zero);

	return update_thin_pool_params(pool_lv->vg, lp->target_attr,
				       lp->passed_args,
				       pool_lv->le_count,
				       pool_lv->vg->extent_size,
				       &lp->thin_chunk_size_calc_policy,
				       &lp->chunk_size,
				       &lp->discards,
				       &lp->poolmetadata_size,
				       &lp->zero);
}



/*
 * Thin lvconvert version which
 *  rename metadata
 *  convert/layers thinpool over data
 *  attach metadata
 */
static int _lvconvert_to_pool(struct cmd_context *cmd,
			      struct logical_volume *pool_lv,
			      struct lvconvert_params *lp)
{
	int r = 0;
	uint64_t min_metadata_size;
	uint64_t max_metadata_size;
	const char *old_name;
	struct lv_segment *seg;
	struct logical_volume *data_lv;
	struct logical_volume *metadata_lv;
	struct logical_volume *pool_metadata_lv;
	struct logical_volume *external_lv = NULL;
	char metadata_name[NAME_LEN], data_name[NAME_LEN];
	int activate_pool;

	if (!lv_is_visible(pool_lv)) {
		log_error("Can't convert internal LV %s/%s.",
			  pool_lv->vg->name, pool_lv->name);
		return 0;
	}

	if (lv_is_mirrored(pool_lv) && !lv_is_raid_type(pool_lv)) {
		log_error("Mirror logical volumes cannot be used as thinpools.\n"
			  "Try \"raid1\" segment type instead.");
		return 0;
	}

	if (lp->thin) {
		if (strcmp(pool_lv->name, lp->pool_data_lv_name) == 0) {
			log_error("Can't use same LV %s/%s for thin pool and thin volume.",
				  pool_lv->vg->name, pool_lv->name);
			return 0;
		}

		external_lv = pool_lv;
		if (!(pool_lv = find_lv(external_lv->vg, lp->pool_data_lv_name))) {
			log_error("Can't find pool LV %s/%s.",
				  external_lv->vg->name, lp->pool_data_lv_name);
			return 0;
		}

		if (lv_is_thin_pool(external_lv)) {
			log_error("Can't convert pool \"%s/%s\" to external origin.",
				  external_lv->vg->name, lp->pool_data_lv_name);
			return 0;
		}

		if (lv_is_thin_pool(pool_lv)) {
			activate_pool = lv_is_active(pool_lv);
			r = 1; /* Already existing thin pool */
			goto out;
		}
	}

	data_lv = pool_lv;
	if (lv_is_thin_type(pool_lv) && !lp->pool_metadata_lv_name) {
		log_error("Can't use thin logical volume %s/%s for thin pool data.",
			  pool_lv->vg->name, pool_lv->name);
		return 0;
	}

	if (segtype_is_cache_pool(lp->segtype))
		activate_pool = 0; /* Cannot activate cache pool */
	else
		/* Allow to have only thinpool active and restore it's active state */
		activate_pool = lv_is_active(pool_lv);

	/* We are changing target type, so deactivate first */
	if (!deactivate_lv(cmd, pool_lv)) {
		log_error("Aborting. Failed to deactivate logical volume %s/%s.",
			  pool_lv->vg->name, pool_lv->name);
		return 0;
	}

	if (lv_is_thin_pool(pool_lv) && pool_is_active(pool_lv)) {
		/* If any thin volume is also active - abort here */
		log_error("Cannot convert pool %s/%s with active thin volumes.",
			  pool_lv->vg->name, pool_lv->name);
		return 0;
	}

	if ((dm_snprintf(metadata_name, sizeof(metadata_name), "%s%s",
			 pool_lv->name,
			 (segtype_is_cache_pool(lp->segtype)) ?
			  "_cmeta" : "_tmeta") < 0) ||
	    (dm_snprintf(data_name, sizeof(data_name), "%s%s",
			 pool_lv->name,
			 (segtype_is_cache_pool(lp->segtype)) ?
			 "_cdata" : "_tdata") < 0)) {
		log_error("Failed to create internal lv names, "
			  "pool name is too long.");
		return 0;
	}

	if (!lp->pool_metadata_lv_name) {
		if (!_lvconvert_update_pool_params(pool_lv, lp))
			return_0;

		if (!get_stripe_params(cmd, &lp->stripes, &lp->stripe_size))
			return_0;

		if (!(metadata_lv = alloc_pool_metadata(pool_lv, metadata_name,
							lp->read_ahead, lp->stripes,
							lp->stripe_size,
							lp->poolmetadata_size,
							lp->alloc, lp->pvh)))
			return_0;
	} else {
		if (!(metadata_lv = find_lv(pool_lv->vg, lp->pool_metadata_lv_name))) {
			log_error("Unknown metadata LV %s.", lp->pool_metadata_lv_name);
			return 0;
		}
		if (!lv_is_visible(metadata_lv)) {
			log_error("Can't convert internal LV %s/%s.",
				  metadata_lv->vg->name, metadata_lv->name);
			return 0;
		}
		if (lv_is_mirrored(pool_lv) && !lv_is_raid_type(pool_lv)) {
			log_error("Mirror logical volumes cannot be used"
				  " for thinpool metadata.\n"
				  "Try \"raid1\" segment type instead.");
			return 0;
		}
		if (metadata_lv->status & LOCKED) {
			log_error("Can't convert locked LV %s/%s.",
				  metadata_lv->vg->name, metadata_lv->name);
			return 0;
		}
		if (metadata_lv == pool_lv) {
			log_error("Can't use same LV for thin pool data and metadata LV %s.",
				  lp->pool_metadata_lv_name);
			return 0;
		}
		if (lv_is_thin_type(metadata_lv)) {
			log_error("Can't use thin pool logical volume %s/%s "
				  "for thin pool metadata.",
				  metadata_lv->vg->name, metadata_lv->name);
			return 0;
		}

		/* Swap normal LV with pool's metadata LV ? */
		if (lv_is_thin_pool(pool_lv)) {
			if (!deactivate_lv(cmd, metadata_lv)) {
				log_error("Aborting. Failed to deactivate thin metadata lv.");
				return 0;
			}
			if (!lp->yes &&
			    yes_no_prompt("Do you want to swap metadata of %s/%s pool with "
					  "volume %s/%s? [y/n]: ",
					  pool_lv->vg->name, pool_lv->name,
					  pool_lv->vg->name, metadata_lv->name) == 'n') {
				log_error("Conversion aborted.");
				return 0;
			}
			seg = first_seg(pool_lv);
			/* Swap names between old and new metadata LV */
			if (!detach_pool_metadata_lv(seg, &pool_metadata_lv))
				return_0;
			old_name = metadata_lv->name;
			if (!lv_rename_update(cmd, metadata_lv, "pvmove_tmeta", 0))
				return_0;
			if (!lv_rename_update(cmd, pool_metadata_lv, old_name, 0))
				return_0;

			if (!arg_count(cmd, chunksize_ARG))
				lp->chunk_size = seg->chunk_size;
			else if ((lp->chunk_size != seg->chunk_size) &&
				 !lp->force &&
				 yes_no_prompt("Do you really want to change chunk size %s to %s for %s/%s "
					       "pool volume? [y/n]: ", display_size(cmd, seg->chunk_size),
					       display_size(cmd, lp->chunk_size),
					       pool_lv->vg->name, pool_lv->name) == 'n') {
				log_error("Conversion aborted.");
				return 0;
			}
			if (!arg_count(cmd, discards_ARG))
				lp->discards = seg->discards;
			if (!arg_count(cmd, zero_ARG))
				lp->zero = seg->zero_new_blocks;

			goto mda_write;
		}

		if (!deactivate_lv(cmd, metadata_lv)) {
			log_error("Aborting. Failed to deactivate thin metadata lv.");
			return 0;
		}

		lp->poolmetadata_size = metadata_lv->size;
		max_metadata_size = (segtype_is_cache_pool(lp->segtype)) ?
			DEFAULT_CACHE_POOL_MAX_METADATA_SIZE * 2 :
			DEFAULT_THIN_POOL_MAX_METADATA_SIZE * 2;
		min_metadata_size = (segtype_is_cache_pool(lp->segtype)) ?
			DEFAULT_CACHE_POOL_MIN_METADATA_SIZE * 2 :
			DEFAULT_THIN_POOL_MIN_METADATA_SIZE * 2;

		if (lp->poolmetadata_size > max_metadata_size) {
			log_warn("WARNING: Maximum size used by metadata is %s, rest is unused.",
				 display_size(cmd, max_metadata_size));
			lp->poolmetadata_size = max_metadata_size;
		} else if (lp->poolmetadata_size < min_metadata_size) {
			log_error("Logical volume %s/%s is too small (<%s) for metadata.",
				  metadata_lv->vg->name, metadata_lv->name,
				  display_size(cmd, min_metadata_size));
			return 0;
		}
		if (!_lvconvert_update_pool_params(pool_lv, lp))
			return_0;

		metadata_lv->status |= LV_TEMPORARY;
		if (!activate_lv_local(cmd, metadata_lv)) {
			log_error("Aborting. Failed to activate metadata lv.");
			return 0;
		}

		if (!wipe_lv(metadata_lv, (struct wipe_params) { .do_zero = 1 })) {
			log_error("Aborting. Failed to wipe metadata lv.");
			return 0;
		}
	}

	if (!deactivate_lv(cmd, metadata_lv)) {
		log_error("Aborting. Failed to deactivate metadata lv. "
			  "Manual intervention required.");
		return 0;
	}

	if (!handle_pool_metadata_spare(pool_lv->vg, metadata_lv->le_count,
					lp->pvh, lp->poolmetadataspare))
		return_0;

	old_name = data_lv->name; /* Use for pool name */
	/*
	 * Since we wish to have underlaying devs to match _[ct]data
	 * rename data LV to match pool LV subtree first,
	 * also checks for visible LV.
	 */
	/* FIXME: any more types prohibited here? */
	if (!lv_rename_update(cmd, data_lv, data_name, 0))
		return_0;

	if (!(pool_lv = lv_create_empty(old_name, NULL,
					((segtype_is_cache_pool(lp->segtype)) ?
					 CACHE_POOL : THIN_POOL) |
					VISIBLE_LV | LVM_READ | LVM_WRITE,
					ALLOC_INHERIT, data_lv->vg))) {
		log_error("Creation of pool LV failed.");
		return 0;
	}

	/* Allocate a new linear segment */
	if (!(seg = alloc_lv_segment(lp->segtype, pool_lv, 0, data_lv->le_count,
				     pool_lv->status, 0, NULL, NULL, 1,
				     data_lv->le_count, 0, 0, 0, NULL)))
		return_0;

	/* Add the new segment to the layer LV */
	dm_list_add(&pool_lv->segments, &seg->list);
	pool_lv->le_count = data_lv->le_count;
	pool_lv->size = data_lv->size;

	if (!attach_pool_data_lv(seg, data_lv))
		return_0;

	/* FIXME: revert renamed LVs in fail path? */
	/* FIXME: any common code with metadata/thin_manip.c  extend_pool() ? */

	seg->low_water_mark = 0;
	seg->transaction_id = 0;

mda_write:
	seg->chunk_size = lp->chunk_size;
	seg->discards = lp->discards;
	seg->zero_new_blocks = lp->zero ? 1 : 0;

	/* Rename deactivated metadata LV to have _tmeta suffix */
	/* Implicit checks if metadata_lv is visible */
	if (lp->pool_metadata_lv_name &&
	    !lv_rename_update(cmd, metadata_lv, metadata_name, 0))
		return_0;

	if (!attach_pool_metadata_lv(seg, metadata_lv))
		return_0;

	if (!vg_write(pool_lv->vg) || !vg_commit(pool_lv->vg))
		return_0;

	if (activate_pool &&
	    !activate_lv_excl(cmd, pool_lv)) {
		log_error("Failed to activate pool logical volume %s/%s.",
			  pool_lv->vg->name, pool_lv->name);
		/* Deactivate subvolumes */
		if (!deactivate_lv(cmd, seg_lv(seg, 0)))
			log_error("Failed to deactivate pool data logical volume.");
		if (!deactivate_lv(cmd, seg->metadata_lv))
			log_error("Failed to deactivate pool metadata logical volume.");
		goto out;
	}

	log_print_unless_silent("Converted %s/%s to %s pool.",
				pool_lv->vg->name, pool_lv->name,
				(segtype_is_cache_pool(lp->segtype)) ?
				"cache" : "thin");

	r = 1;
out:
	if (r && external_lv &&
	    !(r = _lvconvert_thinpool_external(cmd, pool_lv, external_lv, lp)))
		stack;

	backup(pool_lv->vg);

	return r;
}

static int _lvconvert_cache(struct logical_volume *origin,
			    struct lvconvert_params *lp)
{
	struct cmd_context *cmd = origin->vg->cmd;
	struct logical_volume *cache_lv;
	struct logical_volume *cachepool;

	if (!lp->cachepool) {
		log_error("--cachepool argument is required.");
		return 0;
	}

	if (!(cachepool = find_lv(origin->vg, lp->cachepool))) {
		log_error("Unable to find cache pool LV, %s", lp->cachepool);
		return 0;
	}

	if (!(cache_lv = lv_cache_create(cachepool, origin)))
		return_0;

	if (!vg_write(cache_lv->vg))
		return_0;
	if (!suspend_lv(cmd, cache_lv))
		return_0;
	if (!vg_commit(cache_lv->vg))
		return_0;
	if (!resume_lv(cmd, cache_lv))
		return_0;

	log_print_unless_silent("%s/%s is now cached.",
				cache_lv->vg->name, cache_lv->name);

	return 1;
}

static int _lvconvert_single(struct cmd_context *cmd, struct logical_volume *lv,
			     void *handle)
{
	struct lvconvert_params *lp = handle;
	struct dm_list *failed_pvs;

	if (lv->status & LOCKED) {
		log_error("Cannot convert locked LV %s", lv->name);
		return ECMD_FAILED;
	}

	if (lv_is_cow(lv) && !lp->merge && !lp->splitsnapshot) {
		log_error("Can't convert snapshot logical volume \"%s\"",
			  lv->name);
		return ECMD_FAILED;
	}

	if (lv->status & PVMOVE) {
		log_error("Unable to convert pvmove LV %s", lv->name);
		return ECMD_FAILED;
	}

	if (lp->splitsnapshot)
		return _lvconvert_splitsnapshot(cmd, lv, lp);

	if (arg_count(cmd, repair_ARG) && lv_is_thin_pool(lv))
		return _lvconvert_thinpool_repair(cmd, lv, lp);

	if (arg_count(cmd, repair_ARG) &&
	    !(lv->status & MIRRORED) && !(lv->status & RAID)) {
		if (arg_count(cmd, use_policies_ARG))
			return ECMD_PROCESSED; /* nothing to be done here */
		log_error("Can't repair LV \"%s\" of segtype %s.",
			  lv->name,
			  first_seg(lv)->segtype->ops->name(first_seg(lv)));
		return ECMD_FAILED;
	}

	if (!lp->segtype) {
		/* segtype not explicitly set in _read_params */
		lp->segtype = first_seg(lv)->segtype;

		/*
		 * If we are converting to mirror/raid1 and
		 * the segtype was not specified, then we need
		 * to consult the default.
		 */
		if (arg_count(cmd, mirrors_ARG) && !lv_is_mirrored(lv)) {
			lp->segtype = get_segtype_from_string(cmd, find_config_tree_str(cmd, global_mirror_segtype_default_CFG, NULL));
			if (!lp->segtype)
				return_0;
		}
	}
	if (lp->merge) {
		if ((lv_is_thin_volume(lv) && !_lvconvert_merge_thin_snapshot(cmd, lv, lp)) ||
		    (!lv_is_thin_volume(lv) && !_lvconvert_merge_old_snapshot(cmd, lv, lp))) {
			log_print_unless_silent("Unable to merge LV \"%s\" into its origin.", lv->name);
			return ECMD_FAILED;
		}
	} else if (lp->snapshot) {
		if (!_lvconvert_snapshot(cmd, lv, lp))
			return_ECMD_FAILED;

	} else if (segtype_is_cache(lp->segtype)) {
		if (!archive(lv->vg))
			return_ECMD_FAILED;

		if (!_lvconvert_cache(lv, lp))
			return_ECMD_FAILED;

	} else if (segtype_is_cache_pool(lp->segtype)) {
		if (!archive(lv->vg))
			return_ECMD_FAILED;

		if (!_lvconvert_to_pool(cmd, lv, lp))
			return_ECMD_FAILED;

	} else if (arg_count(cmd, thinpool_ARG)) {
		if (!archive(lv->vg))
			return_ECMD_FAILED;

		if (!_lvconvert_to_pool(cmd, lv, lp))
			return_ECMD_FAILED;

	} else if (segtype_is_raid(lp->segtype) ||
		   (lv->status & RAID) || lp->merge_mirror) {
		if (!archive(lv->vg))
			return_ECMD_FAILED;

		if (!_lvconvert_raid(lv, lp))
			return_ECMD_FAILED;

		if (!(failed_pvs = _failed_pv_list(lv->vg)))
			return_ECMD_FAILED;

		/* If repairing and using policies, remove missing PVs from VG */
		if (arg_count(cmd, repair_ARG) && arg_count(cmd, use_policies_ARG))
			_remove_missing_empty_pv(lv->vg, failed_pvs);
	} else if (arg_count(cmd, mirrors_ARG) ||
		   arg_count(cmd, splitmirrors_ARG) ||
		   (lv->status & MIRRORED)) {
		if (!archive(lv->vg))
			return_ECMD_FAILED;

		if (!_lvconvert_mirrors(cmd, lv, lp))
			return_ECMD_FAILED;

		if (!(failed_pvs = _failed_pv_list(lv->vg)))
			return_ECMD_FAILED;

		/* If repairing and using policies, remove missing PVs from VG */
		if (arg_count(cmd, repair_ARG) && arg_count(cmd, use_policies_ARG))
			_remove_missing_empty_pv(lv->vg, failed_pvs);
	}

	return ECMD_PROCESSED;
}

/*
 * FIXME move to toollib along with the rest of the drop/reacquire
 * VG locking that is used by _lvconvert_merge_single()
 */
static struct logical_volume *get_vg_lock_and_logical_volume(struct cmd_context *cmd,
							     const char *vg_name,
							     const char *lv_name)
{
	/*
	 * Returns NULL if the requested LV doesn't exist;
	 * otherwise the caller must release_vg(lv->vg)
	 * - it is also up to the caller to unlock_vg() as needed
	 */
	struct volume_group *vg;
	struct logical_volume* lv = NULL;

	vg = _get_lvconvert_vg(cmd, vg_name, NULL);
	if (vg_read_error(vg)) {
		release_vg(vg);
		return_NULL;
	}

	if (!(lv = _get_lvconvert_lv(cmd, vg, lv_name, NULL, 0))) {
		log_error("Can't find LV %s in VG %s", lv_name, vg_name);
		unlock_and_release_vg(cmd, vg, vg_name);
		return NULL;
	}

	return lv;
}

static int _poll_logical_volume(struct cmd_context *cmd, struct logical_volume *lv,
			       int wait_completion)
{
	struct lvinfo info;

	if (!lv_info(cmd, lv, 0, &info, 0, 0) || !info.exists) {
		log_print_unless_silent("Conversion starts after activation.");
		return ECMD_PROCESSED;
	}

	return lvconvert_poll(cmd, lv, wait_completion ? 0 : 1U);
}

static int lvconvert_single(struct cmd_context *cmd, struct lvconvert_params *lp)
{
	struct logical_volume *lv = NULL;
	int ret = ECMD_FAILED;
	int saved_ignore_suspended_devices = ignore_suspended_devices();

	if (arg_count(cmd, repair_ARG)) {
		init_ignore_suspended_devices(1);
		cmd->handles_missing_pvs = 1;
	}

	lv = get_vg_lock_and_logical_volume(cmd, lp->vg_name, lp->lv_name);
	if (!lv)
		goto_out;

	if (!get_pool_params(cmd, lv_config_profile(lv),
			     &lp->passed_args, &lp->thin_chunk_size_calc_policy,
			     &lp->chunk_size, &lp->discards,
			     &lp->poolmetadata_size, &lp->zero))
		goto_bad;

	/*
	 * lp->pvh holds the list of PVs available for allocation or removal
	 */
	if (lp->pv_count) {
		if (!(lp->pvh = create_pv_list(cmd->mem, lv->vg, lp->pv_count,
					      lp->pvs, 0)))
			goto_bad;
	} else
		lp->pvh = &lv->vg->pvs;

	if (lp->replace_pv_count &&
	    !(lp->replace_pvh = create_pv_list(cmd->mem, lv->vg,
					       lp->replace_pv_count,
					       lp->replace_pvs, 0)))
			goto_bad;

	lp->lv_to_poll = lv;
	ret = _lvconvert_single(cmd, lv, lp);
bad:
	unlock_vg(cmd, lp->vg_name);

	if (ret == ECMD_PROCESSED && lp->need_polling)
		ret = _poll_logical_volume(cmd, lp->lv_to_poll,
					  lp->wait_completion);

	release_vg(lv->vg);
out:
	init_ignore_suspended_devices(saved_ignore_suspended_devices);
	return ret;
}

static int _lvconvert_merge_single(struct cmd_context *cmd, struct logical_volume *lv,
				  void *handle)
{
	struct lvconvert_params *lp = handle;
	const char *vg_name = NULL;
	struct logical_volume *refreshed_lv = NULL;
	int ret;

	/*
	 * FIXME can't trust lv's VG to be current given that caller
	 * is process_each_lv() -- _poll_logical_volume() may have
	 * already updated the VG's metadata in an earlier iteration.
	 * - preemptively drop the VG lock, as is needed for
	 *   _poll_logical_volume(), refresh LV (and VG in the process).
	 */
	vg_name = lv->vg->name;
	unlock_vg(cmd, vg_name);
	refreshed_lv = get_vg_lock_and_logical_volume(cmd, vg_name, lv->name);
	if (!refreshed_lv) {
		log_error("ABORTING: Can't reread LV %s/%s", vg_name, lv->name);
		return ECMD_FAILED;
	}

	lp->lv_to_poll = refreshed_lv;
	ret = _lvconvert_single(cmd, refreshed_lv, lp);

	if (ret == ECMD_PROCESSED && lp->need_polling) {
		/*
		 * Must drop VG lock, because lvconvert_poll() needs it,
		 * then reacquire it after polling completes
		 */
		unlock_vg(cmd, vg_name);

		ret = _poll_logical_volume(cmd, lp->lv_to_poll,
					  lp->wait_completion);

		/* use LCK_VG_WRITE to match lvconvert()'s READ_FOR_UPDATE */
		if (!lock_vol(cmd, vg_name, LCK_VG_WRITE, NULL)) {
			log_error("ABORTING: Can't relock VG for %s "
				  "after polling finished", vg_name);
			ret = ECMD_FAILED;
		}
	}

	release_vg(refreshed_lv->vg);

	return ret;
}

int lvconvert(struct cmd_context * cmd, int argc, char **argv)
{
	struct lvconvert_params lp;

	if (!_read_params(&lp, cmd, argc, argv)) {
		stack;
		return EINVALID_CMD_LINE;
	}

	if (lp.merge) {
		if (!argc) {
			log_error("Please provide logical volume path");
			return EINVALID_CMD_LINE;
		}
		return process_each_lv(cmd, argc, argv, READ_FOR_UPDATE, &lp,
				       &_lvconvert_merge_single);
	}

	return lvconvert_single(cmd, &lp);
}