lvm2/lib/metadata/vg.c

/*
 * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
 * Copyright (C) 2004-2010 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 "lib.h"
#include "metadata.h"
#include "display.h"
#include "activate.h"
#include "toolcontext.h"
#include "lvmcache.h"

struct volume_group *alloc_vg(const char *pool_name, struct cmd_context *cmd,
			      const char *vg_name)
{
	struct dm_pool *vgmem;
	struct volume_group *vg;

	if (!(vgmem = dm_pool_create(pool_name, VG_MEMPOOL_CHUNK)) ||
	    !(vg = dm_pool_zalloc(vgmem, sizeof(*vg)))) {
		log_error("Failed to allocate volume group structure");
		if (vgmem)
			dm_pool_destroy(vgmem);
		return NULL;
	}

	if (vg_name && !(vg->name = dm_pool_strdup(vgmem, vg_name))) {
		log_error("Failed to allocate VG name.");
		dm_pool_destroy(vgmem);
		return NULL;
	}

	vg->cmd = cmd;
	vg->vgmem = vgmem;
	vg->alloc = ALLOC_NORMAL;

	if (!(vg->hostnames = dm_hash_create(16))) {
		log_error("Failed to allocate VG hostname hashtable.");
		dm_pool_destroy(vgmem);
		return NULL;
	}

	dm_list_init(&vg->pvs);
	dm_list_init(&vg->pvs_to_create);
	dm_list_init(&vg->lvs);
	dm_list_init(&vg->tags);
	dm_list_init(&vg->removed_pvs);

	log_debug("Allocated VG %s at %p.", vg->name, vg);

	return vg;
}

static void _free_vg(struct volume_group *vg)
{
	vg_set_fid(vg, NULL);

	if (vg->cmd && vg->vgmem == vg->cmd->mem) {
		log_error(INTERNAL_ERROR "global memory pool used for VG %s",
			  vg->name);
		return;
	}

	log_debug("Freeing VG %s at %p.", vg->name, vg);

	dm_hash_destroy(vg->hostnames);
	dm_pool_destroy(vg->vgmem);
}

void release_vg(struct volume_group *vg)
{
	if (!vg || (vg->fid && vg == vg->fid->fmt->orphan_vg))
		return;

	/* Check if there are any vginfo holders */
	if (vg->vginfo &&
	    !lvmcache_vginfo_holders_dec_and_test_for_zero(vg->vginfo))
		return;

	_free_vg(vg);
}

/*
 * FIXME out of place, but the main (cmd) pool has been already
 * destroyed and touching the fid (also via release_vg) will crash the
 * program
 *
 * For now quick wrapper to allow destroy of orphan vg
 */
void free_orphan_vg(struct volume_group *vg)
{
	_free_vg(vg);
}

char *vg_fmt_dup(const struct volume_group *vg)
{
	if (!vg->fid || !vg->fid->fmt)
		return NULL;
	return dm_pool_strdup(vg->vgmem, vg->fid->fmt->name);
}

char *vg_name_dup(const struct volume_group *vg)
{
	return dm_pool_strdup(vg->vgmem, vg->name);
}

char *vg_system_id_dup(const struct volume_group *vg)
{
	return dm_pool_strdup(vg->vgmem, vg->system_id);
}

char *vg_uuid_dup(const struct volume_group *vg)
{
	return id_format_and_copy(vg->vgmem, &vg->id);
}

char *vg_tags_dup(const struct volume_group *vg)
{
	return tags_format_and_copy(vg->vgmem, &vg->tags);
}

uint32_t vg_seqno(const struct volume_group *vg)
{
	return vg->seqno;
}

uint64_t vg_status(const struct volume_group *vg)
{
	return vg->status;
}

uint64_t vg_size(const struct volume_group *vg)
{
	return (uint64_t) vg->extent_count * vg->extent_size;
}

uint64_t vg_free(const struct volume_group *vg)
{
	return (uint64_t) vg->free_count * vg->extent_size;
}

uint64_t vg_extent_size(const struct volume_group *vg)
{
	return (uint64_t) vg->extent_size;
}

uint64_t vg_extent_count(const struct volume_group *vg)
{
	return (uint64_t) vg->extent_count;
}

uint64_t vg_free_count(const struct volume_group *vg)
{
	return (uint64_t) vg->free_count;
}

uint64_t vg_pv_count(const struct volume_group *vg)
{
	return (uint64_t) vg->pv_count;
}

uint64_t vg_max_pv(const struct volume_group *vg)
{
	return (uint64_t) vg->max_pv;
}

uint64_t vg_max_lv(const struct volume_group *vg)
{
	return (uint64_t) vg->max_lv;
}

unsigned snapshot_count(const struct volume_group *vg)
{
	struct lv_list *lvl;
	unsigned num_snapshots = 0;

	dm_list_iterate_items(lvl, &vg->lvs)
		if (lv_is_cow(lvl->lv))
			num_snapshots++;

	return num_snapshots;
}

unsigned vg_visible_lvs(const struct volume_group *vg)
{
	struct lv_list *lvl;
	unsigned lv_count = 0;

	dm_list_iterate_items(lvl, &vg->lvs) {
		if (lv_is_visible(lvl->lv))
			lv_count++;
	}

	return lv_count;
}

uint32_t vg_mda_count(const struct volume_group *vg)
{
	return dm_list_size(&vg->fid->metadata_areas_in_use) +
		dm_list_size(&vg->fid->metadata_areas_ignored);
}

uint32_t vg_mda_used_count(const struct volume_group *vg)
{
       uint32_t used_count = 0;
       struct metadata_area *mda;

	/*
	 * Ignored mdas could be on either list - the reason being the state
	 * may have changed from ignored to un-ignored and we need to write
	 * the state to disk.
	 */
       dm_list_iterate_items(mda, &vg->fid->metadata_areas_in_use)
	       if (!mda_is_ignored(mda))
		       used_count++;

       return used_count;
}

uint32_t vg_mda_copies(const struct volume_group *vg)
{
	return vg->mda_copies;
}

uint64_t vg_mda_size(const struct volume_group *vg)
{
	return find_min_mda_size(&vg->fid->metadata_areas_in_use);
}

uint64_t vg_mda_free(const struct volume_group *vg)
{
	uint64_t freespace = UINT64_MAX, mda_free;
	struct metadata_area *mda;

	dm_list_iterate_items(mda, &vg->fid->metadata_areas_in_use) {
		if (!mda->ops->mda_free_sectors)
			continue;
		mda_free = mda->ops->mda_free_sectors(mda);
		if (mda_free < freespace)
			freespace = mda_free;
	}

	if (freespace == UINT64_MAX)
		freespace = UINT64_C(0);
	return freespace;
}

int vg_set_mda_copies(struct volume_group *vg, uint32_t mda_copies)
{
	vg->mda_copies = mda_copies;

	/* FIXME Use log_verbose when this is due to specific cmdline request. */
	log_debug("Setting mda_copies to %"PRIu32" for VG %s",
		    mda_copies, vg->name);

	return 1;
}

static int _recalc_extents(uint32_t *extents, const char *desc1,
			   const char *desc2, uint32_t old_size,
			   uint32_t new_size)
{
	uint64_t size = (uint64_t) old_size * (*extents);

	if (size % new_size) {
		log_error("New size %" PRIu64 " for %s%s not an exact number "
			  "of new extents.", size, desc1, desc2);
		return 0;
	}

	size /= new_size;

	if (size > MAX_EXTENT_COUNT) {
		log_error("New extent count %" PRIu64 " for %s%s exceeds "
			  "32 bits.", size, desc1, desc2);
		return 0;
	}

	*extents = (uint32_t) size;

	return 1;
}

int vg_set_extent_size(struct volume_group *vg, uint32_t new_size)
{
	uint32_t old_size = vg->extent_size;
	struct pv_list *pvl;
	struct lv_list *lvl;
	struct physical_volume *pv;
	struct logical_volume *lv;
	struct lv_segment *seg;
	struct pv_segment *pvseg;
	uint32_t s;

	if (!vg_is_resizeable(vg)) {
		log_error("Volume group \"%s\" must be resizeable "
			  "to change PE size", vg->name);
		return 0;
	}

	if (!new_size) {
		log_error("Physical extent size may not be zero");
		return 0;
	}

	if (new_size == vg->extent_size)
		return 1;

	if (new_size & (new_size - 1)) {
		log_error("Physical extent size must be a power of 2.");
		return 0;
	}

	if (new_size > vg->extent_size) {
		if ((uint64_t) vg_size(vg) % new_size) {
			/* FIXME Adjust used PV sizes instead */
			log_error("New extent size is not a perfect fit");
			return 0;
		}
	}

	vg->extent_size = new_size;

	if (vg->fid->fmt->ops->vg_setup &&
	    !vg->fid->fmt->ops->vg_setup(vg->fid, vg))
		return_0;

	if (!_recalc_extents(&vg->extent_count, vg->name, "", old_size,
			     new_size))
		return_0;

	if (!_recalc_extents(&vg->free_count, vg->name, " free space",
			     old_size, new_size))
		return_0;

	/* foreach PV */
	dm_list_iterate_items(pvl, &vg->pvs) {
		pv = pvl->pv;

		pv->pe_size = new_size;
		if (!_recalc_extents(&pv->pe_count, pv_dev_name(pv), "",
				     old_size, new_size))
			return_0;

		if (!_recalc_extents(&pv->pe_alloc_count, pv_dev_name(pv),
				     " allocated space", old_size, new_size))
			return_0;

		/* foreach free PV Segment */
		dm_list_iterate_items(pvseg, &pv->segments) {
			if (pvseg_is_allocated(pvseg))
				continue;

			if (!_recalc_extents(&pvseg->pe, pv_dev_name(pv),
					     " PV segment start", old_size,
					     new_size))
				return_0;
			if (!_recalc_extents(&pvseg->len, pv_dev_name(pv),
					     " PV segment length", old_size,
					     new_size))
				return_0;
		}
	}

	/* foreach LV */
	dm_list_iterate_items(lvl, &vg->lvs) {
		lv = lvl->lv;

		if (!_recalc_extents(&lv->le_count, lv->name, "", old_size,
				     new_size))
			return_0;

		dm_list_iterate_items(seg, &lv->segments) {
			if (!_recalc_extents(&seg->le, lv->name,
					     " segment start", old_size,
					     new_size))
				return_0;

			if (!_recalc_extents(&seg->len, lv->name,
					     " segment length", old_size,
					     new_size))
				return_0;

			if (!_recalc_extents(&seg->area_len, lv->name,
					     " area length", old_size,
					     new_size))
				return_0;

			if (!_recalc_extents(&seg->extents_copied, lv->name,
					     " extents moved", old_size,
					     new_size))
				return_0;

			/* foreach area */
			for (s = 0; s < seg->area_count; s++) {
				switch (seg_type(seg, s)) {
				case AREA_PV:
					if (!_recalc_extents
					    (&seg_pe(seg, s),
					     lv->name,
					     " pvseg start", old_size,
					     new_size))
						return_0;
					if (!_recalc_extents
					    (&seg_pvseg(seg, s)->len,
					     lv->name,
					     " pvseg length", old_size,
					     new_size))
						return_0;
					break;
				case AREA_LV:
					if (!_recalc_extents
					    (&seg_le(seg, s), lv->name,
					     " area start", old_size,
					     new_size))
						return_0;
					break;
				case AREA_UNASSIGNED:
					log_error("Unassigned area %u found in "
						  "segment", s);
					return 0;
				}
			}
		}

	}

	return 1;
}

int vg_set_max_lv(struct volume_group *vg, uint32_t max_lv)
{
	if (!vg_is_resizeable(vg)) {
		log_error("Volume group \"%s\" must be resizeable "
			  "to change MaxLogicalVolume", vg->name);
		return 0;
	}

	if (!(vg->fid->fmt->features & FMT_UNLIMITED_VOLS)) {
		if (!max_lv)
			max_lv = 255;
		else if (max_lv > 255) {
			log_error("MaxLogicalVolume limit is 255");
			return 0;
		}
	}

	if (max_lv && max_lv < vg_visible_lvs(vg)) {
		log_error("MaxLogicalVolume is less than the current number "
			  "%d of LVs for %s", vg_visible_lvs(vg),
			  vg->name);
		return 0;
	}
	vg->max_lv = max_lv;

	return 1;
}

int vg_set_max_pv(struct volume_group *vg, uint32_t max_pv)
{
	if (!vg_is_resizeable(vg)) {
		log_error("Volume group \"%s\" must be resizeable "
			  "to change MaxPhysicalVolumes", vg->name);
		return 0;
	}

	if (!(vg->fid->fmt->features & FMT_UNLIMITED_VOLS)) {
		if (!max_pv)
			max_pv = 255;
		else if (max_pv > 255) {
			log_error("MaxPhysicalVolume limit is 255");
			return 0;
		}
	}

	if (max_pv && max_pv < vg->pv_count) {
		log_error("MaxPhysicalVolumes is less than the current number "
			  "%d of PVs for \"%s\"", vg->pv_count,
			  vg->name);
		return 0;
	}
	vg->max_pv = max_pv;
	return 1;
}

int vg_set_alloc_policy(struct volume_group *vg, alloc_policy_t alloc)
{
	if (alloc == ALLOC_INHERIT) {
		log_error("Volume Group allocation policy cannot inherit "
			  "from anything");
		return 0;
	}

	if (alloc == vg->alloc)
		return 1;

	vg->alloc = alloc;
	return 1;
}

int vg_set_clustered(struct volume_group *vg, int clustered)
{
	struct lv_list *lvl;

	/*
	 * We do not currently support switching the cluster attribute
	 * on active mirrors or snapshots.
	 */
	dm_list_iterate_items(lvl, &vg->lvs) {
		if (lv_is_mirrored(lvl->lv) && lv_is_active(lvl->lv)) {
			log_error("Mirror logical volumes must be inactive "
				  "when changing the cluster attribute.");
			return 0;
		}

		if (clustered) {
			if (lv_is_origin(lvl->lv) || lv_is_cow(lvl->lv)) {
				log_error("Volume group %s contains snapshots "
					  "that are not yet supported.",
					  vg->name);
				return 0;
			}
		}

		if ((lv_is_origin(lvl->lv) || lv_is_cow(lvl->lv)) &&
		    lv_is_active(lvl->lv)) {
			log_error("Snapshot logical volumes must be inactive "
				  "when changing the cluster attribute.");
			return 0;
		}
	}

	if (clustered)
		vg->status |= CLUSTERED;
	else
		vg->status &= ~CLUSTERED;
	return 1;
}

char *vg_attr_dup(struct dm_pool *mem, const struct volume_group *vg)
{
	char *repstr;

	if (!(repstr = dm_pool_zalloc(mem, 7))) {
		log_error("dm_pool_alloc failed");
		return NULL;
	}

	repstr[0] = (vg->status & LVM_WRITE) ? 'w' : 'r';
	repstr[1] = (vg_is_resizeable(vg)) ? 'z' : '-';
	repstr[2] = (vg_is_exported(vg)) ? 'x' : '-';
	repstr[3] = (vg_missing_pv_count(vg)) ? 'p' : '-';
	repstr[4] = alloc_policy_char(vg->alloc);
	repstr[5] = (vg_is_clustered(vg)) ? 'c' : '-';
	return repstr;
}