lvm2/tools/lvcreate.c

/*
 * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
 * Copyright (C) 2004-2007 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 "lv_alloc.h"

#include <fcntl.h>

struct lvcreate_params {
	/* flags */
	int snapshot;
	int zero;
	int major;
	int minor;
	int corelog;
	int nosync;

	char *origin;
	const char *vg_name;
	const char *lv_name;

	uint32_t stripes;
	uint32_t stripe_size;
	uint32_t chunk_size;
	uint32_t region_size;

	uint32_t mirrors;

	const struct segment_type *segtype;

	/* size */
	uint32_t extents;
	uint64_t size;
	uint32_t voriginextents;
	uint64_t voriginsize;
	percent_t percent;

	uint32_t permission;
	uint32_t read_ahead;
	alloc_policy_t alloc;

	int pv_count;
	char **pvs;
};

static int _lvcreate_name_params(struct lvcreate_params *lp,
				 struct cmd_context *cmd,
				 int *pargc, char ***pargv)
{
	int argc = *pargc;
	char **argv = *pargv, *ptr;
	char *vg_name;

	if (arg_count(cmd, name_ARG))
		lp->lv_name = arg_value(cmd, name_ARG);

	if (lp->snapshot && !arg_count(cmd, virtualsize_ARG)) {
		if (!argc) {
			log_err("Please specify a logical volume to act as "
				"the snapshot origin.");
			return 0;
		}

		lp->origin = argv[0];
		(*pargv)++, (*pargc)--;
		if (!(lp->vg_name = extract_vgname(cmd, lp->origin))) {
			log_err("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;

	} else {
		/*
		 * If VG not on command line, try -n arg and then
		 * environment.
		 */
		if (!argc) {
			if (!(lp->vg_name = extract_vgname(cmd, lp->lv_name))) {
				log_err("Please provide a volume group name");
				return 0;
			}

		} else {
			vg_name = skip_dev_dir(cmd, argv[0], NULL);
			if (strrchr(vg_name, '/')) {
				log_error("Volume group name expected "
					  "(no slash)");
				return 0;
			}

			/*
			 * Ensure lv_name doesn't contain a
			 * different VG.
			 */
			if (lp->lv_name && strchr(lp->lv_name, '/')) {
				if (!(lp->vg_name =
				      extract_vgname(cmd, lp->lv_name)))
					return 0;

				if (strcmp(lp->vg_name, vg_name)) {
					log_error("Inconsistent volume group "
						  "names "
						  "given: \"%s\" and \"%s\"",
						  lp->vg_name, vg_name);
					return 0;
				}
			}

			lp->vg_name = vg_name;
			(*pargv)++, (*pargc)--;
		}
	}

	if (!validate_name(lp->vg_name)) {
		log_error("Volume group name %s has invalid characters",
			  lp->vg_name);
		return 0;
	}

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

		if (!apply_lvname_restrictions(lp->lv_name))
			return_0;

		if (!validate_name(lp->lv_name)) {
			log_error("Logical volume name \"%s\" is invalid",
				  lp->lv_name);
			return 0;
		}
	}

	return 1;
}

static int _read_size_params(struct lvcreate_params *lp,
			     struct cmd_context *cmd)
{
	if (arg_count(cmd, extents_ARG) + arg_count(cmd, size_ARG) != 1) {
		log_error("Please specify either size or extents (not both)");
		return 0;
	}

	if (arg_count(cmd, extents_ARG)) {
		if (arg_sign_value(cmd, extents_ARG, 0) == SIGN_MINUS) {
			log_error("Negative number of extents is invalid");
			return 0;
		}
		lp->extents = arg_uint_value(cmd, extents_ARG, 0);
		lp->percent = arg_percent_value(cmd, extents_ARG, PERCENT_NONE);
	}

	/* Size returned in kilobyte units; held in sectors */
	if (arg_count(cmd, size_ARG)) {
		if (arg_sign_value(cmd, size_ARG, 0) == SIGN_MINUS) {
			log_error("Negative size is invalid");
			return 0;
		}
		lp->size = arg_uint64_value(cmd, size_ARG, UINT64_C(0));
		lp->percent = PERCENT_NONE;
	}

	/* Size returned in kilobyte units; held in sectors */
	if (arg_count(cmd, virtualsize_ARG)) {
		if (arg_sign_value(cmd, virtualsize_ARG, 0) == SIGN_MINUS) {
			log_error("Negative virtual origin size is invalid");
			return 0;
		}
		lp->voriginsize = arg_uint64_value(cmd, virtualsize_ARG,
						   UINT64_C(0));
		if (!lp->voriginsize) {
			log_error("Virtual origin size may not be zero");
			return 0;
		}
	}

	return 1;
}

/*
 * Generic stripe parameter checks.
 * FIXME: Should eventually be moved into lvm library.
 */
static int _validate_stripe_params(struct cmd_context *cmd,
				   struct lvcreate_params *lp)
{
	if (lp->stripes == 1 && lp->stripe_size) {
		log_print("Ignoring stripesize argument with single stripe");
		lp->stripe_size = 0;
	}

	if (lp->stripes > 1 && !lp->stripe_size) {
		lp->stripe_size = find_config_tree_int(cmd,
						  "metadata/stripesize",
						  DEFAULT_STRIPESIZE) * 2;
		log_print("Using default stripesize %s",
			  display_size(cmd, (uint64_t) lp->stripe_size));
	}

	if (lp->stripes < 1 || lp->stripes > MAX_STRIPES) {
		log_error("Number of stripes (%d) must be between %d and %d",
			  lp->stripes, 1, MAX_STRIPES);
		return 0;
	}

	/* MAX size check is in _lvcreate */
	if (lp->stripes > 1 && (lp->stripe_size < STRIPE_SIZE_MIN ||
				lp->stripe_size & (lp->stripe_size - 1))) {
		log_error("Invalid stripe size %s",
			  display_size(cmd, (uint64_t) lp->stripe_size));
		return 0;
	}

	return 1;
}

/* The stripe size is limited by the size of a uint32_t, but since the
 * value given by the user is doubled, and the final result must be a
 * power of 2, we must divide UINT_MAX by four and add 1 (to round it
 * up to the power of 2) */
static int _read_stripe_params(struct lvcreate_params *lp,
			       struct cmd_context *cmd)
{
	if (arg_count(cmd, stripesize_ARG)) {
		if (arg_sign_value(cmd, stripesize_ARG, 0) == SIGN_MINUS) {
			log_error("Negative stripesize is invalid");
			return 0;
		}
		/* Check to make sure we won't overflow lp->stripe_size */
		if(arg_uint_value(cmd, stripesize_ARG, 0) > STRIPE_SIZE_LIMIT * 2) {
			log_error("Stripe size cannot be larger than %s",
				  display_size(cmd, (uint64_t) STRIPE_SIZE_LIMIT));
			return 0;
		}
		lp->stripe_size = arg_uint_value(cmd, stripesize_ARG, 0);
	}


	if (!_validate_stripe_params(cmd, lp))
		return 0;

	return 1;
}

/*
 * Generic mirror parameter checks.
 * FIXME: Should eventually be moved into lvm library.
 */
static int _validate_mirror_params(const struct cmd_context *cmd __attribute((unused)),
				   const struct lvcreate_params *lp)
{
	int pagesize = lvm_getpagesize();

	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 % (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) {
		log_error("Non-zero region size must be supplied.");
		return 0;
	}

	return 1;
}

static int _read_mirror_params(struct lvcreate_params *lp,
			       struct cmd_context *cmd)
{
	int region_size;
	const char *mirrorlog;

	if (arg_count(cmd, corelog_ARG))
		lp->corelog = 1;

	mirrorlog = arg_str_value(cmd, mirrorlog_ARG,
				  lp->corelog ? "core" : DEFAULT_MIRRORLOG);

	if (!strcmp("disk", mirrorlog)) {
		if (lp->corelog) {
			log_error("--mirrorlog disk and --corelog "
				  "are incompatible");
			return 0;
		}
		lp->corelog = 0;
	} else if (!strcmp("core", mirrorlog))
		lp->corelog = 1;
	else {
		log_error("Unknown mirrorlog type: %s", mirrorlog);
		return 0;
	}

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

	lp->nosync = arg_count(cmd, nosync_ARG) ? 1 : 0;

	if (arg_count(cmd, regionsize_ARG)) {
		if (arg_sign_value(cmd, regionsize_ARG, 0) == SIGN_MINUS) {
			log_error("Negative regionsize is invalid");
			return 0;
		}
		lp->region_size = arg_uint_value(cmd, regionsize_ARG, 0);
	} else {
		region_size = 2 * find_config_tree_int(cmd,
					"activation/mirror_region_size",
					DEFAULT_MIRROR_REGION_SIZE);
		if (region_size < 0) {
			log_error("Negative regionsize in configuration file "
				  "is invalid");
			return 0;
		}
		lp->region_size = region_size;
	}

	if (!_validate_mirror_params(cmd, lp))
		return 0;

	return 1;
}

static int _lvcreate_params(struct lvcreate_params *lp, struct cmd_context *cmd,
			    int argc, char **argv)
{
	int contiguous;
	unsigned pagesize;

	memset(lp, 0, sizeof(*lp));

	/*
	 * Check selected options are compatible and determine segtype
	 */
	lp->segtype = (const struct segment_type *)
	    arg_ptr_value(cmd, type_ARG,
			  get_segtype_from_string(cmd, "striped"));

	lp->stripes = arg_uint_value(cmd, stripes_ARG, 1);
	if (arg_count(cmd, stripes_ARG) && lp->stripes == 1)
		log_print("Redundant stripes argument: default is 1");

	if (arg_count(cmd, snapshot_ARG) || seg_is_snapshot(lp) ||
	    arg_count(cmd, virtualsize_ARG))
		lp->snapshot = 1;

	lp->mirrors = 1;

	/* Default to 2 mirrored areas if --type mirror */
	if (seg_is_mirrored(lp))
		lp->mirrors = 2;

	if (arg_count(cmd, mirrors_ARG)) {
		lp->mirrors = arg_uint_value(cmd, mirrors_ARG, 0) + 1;
		if (lp->mirrors == 1)
			log_print("Redundant mirrors argument: default is 0");
		if (arg_sign_value(cmd, mirrors_ARG, 0) == SIGN_MINUS) {
			log_error("Mirrors argument may not be negative");
			return 0;
		}
	}

	if (lp->snapshot) {
		if (arg_count(cmd, zero_ARG)) {
			log_error("-Z is incompatible with snapshots");
			return 0;
		}
		if (arg_sign_value(cmd, chunksize_ARG, 0) == 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;
	} else {
		if (arg_count(cmd, chunksize_ARG)) {
			log_error("-c is only available with snapshots");
			return 0;
		}
	}

	if (lp->mirrors > 1) {
		if (lp->snapshot) {
			log_error("mirrors and snapshots are currently "
				  "incompatible");
			return 0;
		}

		if (lp->stripes > 1) {
			log_error("mirrors and stripes are currently "
				  "incompatible");
			return 0;
		}

		if (!(lp->segtype = get_segtype_from_string(cmd, "striped")))
			return_0;
	} else {
		if (arg_count(cmd, corelog_ARG)) {
			log_error("--corelog is only available with mirrors");
			return 0;
		}

		if (arg_count(cmd, nosync_ARG)) {
			log_error("--nosync is only available with mirrors");
			return 0;
		}
	}

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

	if (!_lvcreate_name_params(lp, cmd, &argc, &argv) ||
	    !_read_size_params(lp, cmd) ||
	    !_read_stripe_params(lp, cmd) ||
	    !_read_mirror_params(lp, cmd))
		return_0;

	/*
	 * Should we zero the lv.
	 */
	lp->zero = strcmp(arg_str_value(cmd, zero_ARG,
		(lp->segtype->flags & SEG_CANNOT_BE_ZEROED) ? "n" : "y"), "n");

	/*
	 * Alloc policy
	 */
	contiguous = strcmp(arg_str_value(cmd, contiguous_ARG, "n"), "n");

	lp->alloc = contiguous ? ALLOC_CONTIGUOUS : ALLOC_INHERIT;

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

	if (contiguous && (lp->alloc != ALLOC_CONTIGUOUS)) {
		log_error("Conflicting contiguous and alloc arguments");
		return 0;
	}

	/*
	 * Read ahead.
	 */
	lp->read_ahead = arg_uint_value(cmd, readahead_ARG, DM_READ_AHEAD_NONE);
	pagesize = lvm_getpagesize() >> SECTOR_SHIFT;
	if (lp->read_ahead != DM_READ_AHEAD_AUTO &&
	    lp->read_ahead != DM_READ_AHEAD_NONE &&
	    lp->read_ahead % pagesize) {
		if (lp->read_ahead < pagesize)
			lp->read_ahead = pagesize;
		else
			lp->read_ahead = (lp->read_ahead / pagesize) * pagesize;
		log_warn("WARNING: Overriding readahead to %u sectors, a multiple "
			    "of %uK page size.", lp->read_ahead, pagesize >> 1);
	}

	/*
	 * Permissions.
	 */
	if (arg_count(cmd, permission_ARG))
		lp->permission = arg_uint_value(cmd, permission_ARG, 0);
	else
		lp->permission = LVM_READ | LVM_WRITE;

	/* Must not zero read only volume */
	if (!(lp->permission & LVM_WRITE))
		lp->zero = 0;

	lp->minor = arg_int_value(cmd, minor_ARG, -1);
	lp->major = arg_int_value(cmd, major_ARG, -1);

	/* Persistent minor */
	if (arg_count(cmd, persistent_ARG)) {
		if (!strcmp(arg_str_value(cmd, persistent_ARG, "n"), "y")) {
			if (lp->minor == -1) {
				log_error("Please specify minor number with "
					  "--minor when using -My");
				return 0;
			}
			if (lp->major == -1) {
				log_error("Please specify major number with "
					  "--major when using -My");
				return 0;
			}
		} else {
			if ((lp->minor != -1) || (lp->major != -1)) {
				log_error("--major and --minor incompatible "
					  "with -Mn");
				return 0;
			}
		}
	} else if (arg_count(cmd, minor_ARG) || arg_count(cmd, major_ARG)) {
		log_error("--major and --minor require -My");
		return 0;
	}

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

	return 1;
}

static uint64_t _extents_from_size(struct cmd_context *cmd, uint64_t size,
				   uint32_t extent_size)
{
	if (size % extent_size) {
		size += extent_size - size % extent_size;
		log_print("Rounding up size to full physical extent %s",
			  display_size(cmd, size));
	}

	if (size > (uint64_t) UINT32_MAX * extent_size) {
		log_error("Volume too large (%s) for extent size %s. "
			  "Upper limit is %s.",
			  display_size(cmd, size),
			  display_size(cmd, (uint64_t) extent_size),
			  display_size(cmd, (uint64_t) UINT32_MAX *
				       extent_size));
		return 0;
	}

	return (uint64_t) size / extent_size;
}

static struct logical_volume *_create_virtual_origin(struct cmd_context *cmd,
						     struct volume_group *vg,
						     const char *lv_name,
						     uint32_t permission,
						     uint64_t voriginextents)
{
	const struct segment_type *segtype;
	size_t len;
	char *vorigin_name;
	struct logical_volume *lv;

	if (!(segtype = get_segtype_from_string(cmd, "zero"))) {
		log_error("Zero segment type for virtual origin not found");
		return NULL;
	}

	len = strlen(lv_name) + 32;
	if (!(vorigin_name = alloca(len)) ||
	    dm_snprintf(vorigin_name, len, "%s_vorigin", lv_name) < 0) {
		log_error("Virtual origin name allocation failed.");
		return NULL;
	}

	if (!(lv = lv_create_empty(vorigin_name, NULL, permission,
				   ALLOC_INHERIT, vg)))
		return_NULL;

	if (!lv_extend(lv, segtype, 1, 0, 1, voriginextents, NULL, 0u, 0u,
		       NULL, ALLOC_INHERIT))
		return_NULL;

	/* store vg on disk(s) */
	if (!vg_write(vg) || !vg_commit(vg))
		return_NULL;

	backup(vg);

	return lv;
}

static int _lvcreate(struct cmd_context *cmd, struct volume_group *vg,
		     struct lvcreate_params *lp)
{
	uint32_t size_rest;
	uint32_t status = 0;
	struct logical_volume *lv, *org = NULL;
	struct dm_list *pvh;
	const char *tag = NULL;
	int origin_active = 0;
	char lv_name_buf[128];
	const char *lv_name;
	struct lvinfo info;
	uint32_t pv_extent_count;

	if (lp->lv_name && find_lv_in_vg(vg, lp->lv_name)) {
		log_error("Logical volume \"%s\" already exists in "
			  "volume group \"%s\"", lp->lv_name, lp->vg_name);
		return 0;
	}

	if (vg_max_lv_reached(vg)) {
		log_error("Maximum number of logical volumes (%u) reached "
			  "in volume group %s", vg->max_lv, vg->name);
		return 0;
	}

	if (lp->mirrors > 1 && !(vg->fid->fmt->features & FMT_SEGMENTS)) {
		log_error("Metadata does not support mirroring.");
		return 0;
	}

	if (lp->read_ahead != DM_READ_AHEAD_AUTO &&
	    lp->read_ahead != DM_READ_AHEAD_NONE &&
	    (vg->fid->fmt->features & FMT_RESTRICTED_READAHEAD) &&
	    (lp->read_ahead < 2 || lp->read_ahead > 120)) {
		log_error("Metadata only supports readahead values between 2 and 120.");
		return 0;
	}

	if (lp->stripe_size > vg->extent_size) {
		log_error("Reducing requested stripe size %s to maximum, "
			  "physical extent size %s",
			  display_size(cmd, (uint64_t) lp->stripe_size),
			  display_size(cmd, (uint64_t) vg->extent_size));
		lp->stripe_size = vg->extent_size;
	}

	/* Need to check the vg's format to verify this - the cmd format isn't setup properly yet */
	if (lp->stripes > 1 &&
	    !(vg->fid->fmt->features & FMT_UNLIMITED_STRIPESIZE) &&
	    (lp->stripe_size > STRIPE_SIZE_MAX)) {
		log_error("Stripe size may not exceed %s",
			  display_size(cmd, (uint64_t) STRIPE_SIZE_MAX));
		return 0;
	}

	if (lp->size &&
	    !(lp->extents = _extents_from_size(cmd, lp->size, vg->extent_size)))
		return_0;

	if (lp->voriginsize &&
	    !(lp->voriginextents = _extents_from_size(cmd, lp->voriginsize,
						      vg->extent_size)))
		return_0;

	/*
	 * Create the pv list.
	 */
	if (lp->pv_count) {
		if (!(pvh = create_pv_list(cmd->mem, vg,
					   lp->pv_count, lp->pvs, 1)))
			return_0;
	} else
		pvh = &vg->pvs;

	switch(lp->percent) {
		case PERCENT_VG:
			lp->extents = lp->extents * vg->extent_count / 100;
			break;
		case PERCENT_FREE:
			lp->extents = lp->extents * vg->free_count / 100;
			break;
		case PERCENT_PVS:
			if (!lp->pv_count) {
				log_error("Please specify physical volume(s) "
					  "with %%PVS");
				return 0;
			}
			pv_extent_count = pv_list_extents_free(pvh);
			lp->extents = lp->extents * pv_extent_count / 100;
			break;
		case PERCENT_LV:
			log_error("Please express size as %%VG, %%PVS, or "
				  "%%FREE.");
			return 0;
		case PERCENT_NONE:
			break;
	}

	if ((size_rest = lp->extents % lp->stripes)) {
		log_print("Rounding size (%d extents) up to stripe boundary "
			  "size (%d extents)", lp->extents,
			  lp->extents - size_rest + lp->stripes);
		lp->extents = lp->extents - size_rest + lp->stripes;
	}

	if (lp->zero && !activation()) {
		log_error("Can't wipe start of new LV without using "
			  "device-mapper kernel driver");
		return 0;
	}

	status |= lp->permission | VISIBLE_LV;

	if (lp->snapshot) {
		if (!activation()) {
			log_error("Can't create snapshot without using "
				  "device-mapper kernel driver");
			return 0;
		}
		/* FIXME Allow exclusive activation. */
		if (vg_is_clustered(vg)) {
			log_error("Clustered snapshots are not yet supported.");
			return 0;
		}

		/* Must zero cow */
		status |= LVM_WRITE;

		if (arg_count(cmd, virtualsize_ARG))
			origin_active = 1;
		else {

			if (!(org = find_lv(vg, lp->origin))) {
				log_error("Couldn't find origin volume '%s'.",
					  lp->origin);
				return 0;
			}
			if (lv_is_virtual_origin(org)) {
				log_error("Can't share virtual origins. "
					  "Use --virtualsize.");
				return 0;
			}
			if (lv_is_cow(org)) {
				log_error("Snapshots of snapshots are not "
					  "supported yet.");
				return 0;
			}
			if (org->status & LOCKED) {
				log_error("Snapshots of locked devices are not "
					  "supported yet");
				return 0;
			}
			if (org->status & MIRROR_IMAGE ||
			    org->status & MIRROR_LOG ||
			    org->status & MIRRORED) {
				log_error("Snapshots and mirrors may not yet "
					  "be mixed.");
				return 0;
			}

			if (!lv_info(cmd, org, &info, 0, 0)) {
				log_error("Check for existence of snapshot "
					  "origin '%s' failed.", org->name);
				return 0;
			}
			origin_active = info.exists;
		}
	}

	if (!lp->extents) {
		log_error("Unable to create new logical volume with no extents");
		return 0;
	}

	if (!seg_is_virtual(lp) &&
	    vg->free_count < lp->extents) {
		log_error("Insufficient free extents (%u) in volume group %s: "
			  "%u required", vg->free_count, vg->name, lp->extents);
		return 0;
	}

	if (lp->stripes > dm_list_size(pvh) && lp->alloc != ALLOC_ANYWHERE) {
		log_error("Number of stripes (%u) must not exceed "
			  "number of physical volumes (%d)", lp->stripes,
			  dm_list_size(pvh));
		return 0;
	}

	if (lp->mirrors > 1 && !activation()) {
		log_error("Can't create mirror without using "
			  "device-mapper kernel driver.");
		return 0;
	}

	/* The snapshot segment gets created later */
	if (lp->snapshot &&
	    !(lp->segtype = get_segtype_from_string(cmd, "striped")))
		return_0;

	if (!archive(vg))
		return 0;

	if (lp->lv_name)
		lv_name = lp->lv_name;
	else {
		if (!generate_lv_name(vg, "lvol%d", lv_name_buf, sizeof(lv_name_buf))) {
			log_error("Failed to generate LV name.");
			return 0;
		}
		lv_name = &lv_name_buf[0];
	}

	if (arg_count(cmd, addtag_ARG)) {
		if (!(tag = arg_str_value(cmd, addtag_ARG, NULL))) {
			log_error("Failed to get tag");
			return 0;
		}

		if (!(vg->fid->fmt->features & FMT_TAGS)) {
			log_error("Volume group %s does not support tags",
				  vg->name);
			return 0;
		}
	}

	if (lp->mirrors > 1) {
		init_mirror_in_sync(lp->nosync);

		if (lp->nosync) {
			log_warn("WARNING: New mirror won't be synchronised. "
				  "Don't read what you didn't write!");
			status |= MIRROR_NOTSYNCED;
		}
	}

	if (!(lv = lv_create_empty(lv_name ? lv_name : "lvol%d", NULL,
				   status, lp->alloc, vg)))
		return_0;

	if (lp->read_ahead) {
		log_verbose("Setting read ahead sectors");
		lv->read_ahead = lp->read_ahead;
	}

	if (lp->minor >= 0) {
		lv->major = lp->major;
		lv->minor = lp->minor;
		lv->status |= FIXED_MINOR;
		log_verbose("Setting device number to (%d, %d)", lv->major,
			    lv->minor);
	}

	if (tag && !str_list_add(cmd->mem, &lv->tags, tag)) {
		log_error("Failed to add tag %s to %s/%s",
			  tag, lv->vg->name, lv->name);
		return 0;
	}

	if (!lv_extend(lv, lp->segtype, lp->stripes, lp->stripe_size,
		       1, lp->extents, NULL, 0u, 0u, pvh, lp->alloc))
		return_0;

	if (lp->mirrors > 1) {
		if (!lv_add_mirrors(cmd, lv, lp->mirrors - 1, lp->stripes,
				    adjusted_mirror_region_size(
						vg->extent_size,
						lv->le_count,
						lp->region_size),
				    lp->corelog ? 0U : 1U, pvh, lp->alloc,
				    MIRROR_BY_LV |
				    (lp->nosync ? MIRROR_SKIP_INIT_SYNC : 0))) {
			stack;
			goto revert_new_lv;
		}
	}

	/* store vg on disk(s) */
	if (!vg_write(vg) || !vg_commit(vg))
		return_0;

	backup(vg);

	if (lp->snapshot) {
		if (!activate_lv_excl(cmd, lv)) {
			log_error("Aborting. Failed to activate snapshot "
				  "exception store.");
			goto revert_new_lv;
		}
	} else if (!activate_lv(cmd, lv)) {
		if (lp->zero) {
			log_error("Aborting. Failed to activate new LV to wipe "
				  "the start of it.");
			goto deactivate_and_revert_new_lv;
		}
		log_error("Failed to activate new LV.");
		return 0;
	}

	if (!lp->zero && !lp->snapshot)
		log_error("WARNING: \"%s\" not zeroed", lv->name);
	else if (!set_lv(cmd, lv, UINT64_C(0), 0)) {
		log_error("Aborting. Failed to wipe %s.",
			  lp->snapshot ? "snapshot exception store" :
					 "start of new LV");
		goto deactivate_and_revert_new_lv;
	}

	if (lp->snapshot) {
		/* Reset permission after zeroing */
		if (!(lp->permission & LVM_WRITE))
			lv->status &= ~LVM_WRITE;

		/* COW area must be deactivated if origin is not active */
		if (!origin_active && !deactivate_lv(cmd, lv)) {
			log_error("Aborting. Couldn't deactivate snapshot "
				  "COW area. Manual intervention required.");
			return 0;
		}

		/* A virtual origin must be activated explicitly. */
		if (lp->voriginsize &&
		    (!(org = _create_virtual_origin(cmd, vg, lv->name,
						    lp->permission,
						    lp->voriginextents)) ||
		     !activate_lv(cmd, org))) {
			log_error("Couldn't create virtual origin for LV %s",
				  lv->name);
			if (org && !lv_remove(org))
				stack;
			goto deactivate_and_revert_new_lv;
		}

		/* cow LV remains active and becomes snapshot LV */

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

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

		if (!suspend_lv(cmd, org)) {
			log_error("Failed to suspend origin %s", org->name);
			vg_revert(vg);
			return 0;
		}

		if (!vg_commit(vg))
			return_0;

		if (!resume_lv(cmd, org)) {
			log_error("Problem reactivating origin %s", org->name);
			return 0;
		}
	}
	/* FIXME out of sequence */
	backup(vg);

	log_print("Logical volume \"%s\" created", lv->name);

	/*
	 * FIXME: as a sanity check we could try reading the
	 * last block of the device ?
	 */

	return 1;

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

revert_new_lv:
	/* FIXME Better to revert to backup of metadata? */
	if (!lv_remove(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;
}

int lvcreate(struct cmd_context *cmd, int argc, char **argv)
{
	int r = ECMD_PROCESSED;
	struct lvcreate_params lp;
	struct volume_group *vg;

	memset(&lp, 0, sizeof(lp));

	if (!_lvcreate_params(&lp, cmd, argc, argv))
		return EINVALID_CMD_LINE;

	log_verbose("Finding volume group \"%s\"", lp.vg_name);
	vg = vg_read_for_update(cmd, lp.vg_name, NULL, 0);
	if (vg_read_error(vg)) {
		vg_release(vg);
		return ECMD_FAILED;
	}

	if (!_lvcreate(cmd, vg, &lp))
		r = ECMD_FAILED;

	unlock_and_release_vg(cmd, vg, lp.vg_name);
	return r;
}