lvm2/lib/format1/format1.c

/*
 * Copyright (C) 2001 Sistina Software (UK) Limited.
 *
 * This file is released under the LGPL.
 */

#include "disk-rep.h"
#include "dbg_malloc.h"
#include "pool.h"
#include "hash.h"
#include "limits.h"
#include "list.h"
#include "log.h"
#include "display.h"
#include "toolcontext.h"

/* VG consistency checks */
static int _check_vgs(struct list *pvs, int *partial)
{
	struct list *pvh, *t;
	struct disk_list *dl = NULL;
	struct disk_list *first = NULL;

	int pv_count = 0;
	int exported = -1;

	*partial = 0;

	/*
	 * If there are exported and unexported PVs, ignore exported ones.
	 * This means an active VG won't be affected if disks are inserted
	 * bearing an exported VG with the same name.
	 */
	list_iterate(pvh, pvs) {
		dl = list_item(pvh, struct disk_list);

		if (exported < 0) {
			exported = dl->pvd.pv_status & VG_EXPORTED;
			continue;
		}

		if (exported != (dl->pvd.pv_status & VG_EXPORTED)) {
			/* Remove exported PVs */
			list_iterate_safe(pvh, t, pvs) {
				dl = list_item(pvh, struct disk_list);
				if (dl->pvd.pv_status & VG_EXPORTED)
					list_del(pvh);
			}
			break;
		}
	}


	/* Remove any PVs with VG structs that differ from the first */
	list_iterate_safe(pvh, t, pvs) {
		dl = list_item(pvh, struct disk_list);

		if (!first)
			first = dl;

		else if (memcmp(&first->vgd, &dl->vgd, sizeof(first->vgd))) {
			log_error("VG data differs between PVs %s and %s",
				  dev_name(first->dev), dev_name(dl->dev));
			list_del(pvh);
			if (partial_mode()) {
				*partial = 1;
				continue;
			}
			return 0;
		}
		pv_count++;
	}

	/* On entry to fn, list known to be non-empty */
	if (pv_count != dl->vgd.pv_cur) {
		log_error("%d PV(s) found for VG %s: expected %d",
			  pv_count, dl->pvd.vg_name, dl->vgd.pv_cur);
		if (!partial_mode())
			return 0;
		*partial = 1;
	}

	return 1;
}

static struct volume_group *_build_vg(struct cmd_context *cmd,
				      struct list *pvs)
{
	struct pool *mem = cmd->mem;
	struct volume_group *vg = pool_alloc(mem, sizeof(*vg));
	struct disk_list *dl;
	int partial;

	if (!vg)
		goto bad;

	if (list_empty(pvs))
		goto bad;

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

	vg->cmd = cmd;
	list_init(&vg->pvs);
	list_init(&vg->lvs);
	list_init(&vg->snapshots);

	if (!_check_vgs(pvs, &partial))
		goto bad;

	dl = list_item(pvs->n, struct disk_list);

	if (!import_vg(mem, vg, dl, partial))
		goto bad;

	if (!import_pvs(mem, vg, pvs, &vg->pvs, &vg->pv_count))
		goto bad;

	if (!import_lvs(mem, vg, pvs))
		goto bad;

	if (!import_extents(mem, vg, pvs))
		goto bad;

	if (!import_snapshots(mem, vg, pvs))
		goto bad;

	return vg;

 bad:
	stack;
	pool_free(mem, vg);
	return NULL;
}

static struct volume_group *_vg_read(struct format_instance *fi,
				     const char *vg_name)
{
	struct pool *mem = pool_create(1024 * 10);
	struct list pvs;
	struct volume_group *vg = NULL;
	list_init(&pvs);

	if (!mem) {
		stack;
		return NULL;
	}

        /* Strip dev_dir if present */
	vg_name = strip_dir(vg_name, fi->cmd->dev_dir);

	if (!read_pvs_in_vg(vg_name, fi->cmd->filter, mem, &pvs)) {
		stack;
		goto bad;
	}

	if (!(vg = _build_vg(fi->cmd, &pvs))) {
		stack;
		goto bad;
	}

 bad:
	pool_destroy(mem);
	return vg;
}

static struct disk_list *_flatten_pv(struct pool *mem, struct volume_group *vg,
				     struct physical_volume *pv,
				     const char *dev_dir)
{
	struct disk_list *dl = pool_alloc(mem, sizeof(*dl));

	if (!dl) {
		stack;
		return NULL;
	}

	dl->mem = mem;
	dl->dev = pv->dev;

	list_init(&dl->uuids);
	list_init(&dl->lvds);

	if (!export_pv(mem, vg, &dl->pvd, pv) ||
	    !export_vg(&dl->vgd, vg) ||
	    !export_uuids(dl, vg) ||
	    !export_lvs(dl, vg, pv, dev_dir) ||
	    !calculate_layout(dl)) {
		stack;
		pool_free(mem, dl);
		return NULL;
	}

	return dl;
}

static int _flatten_vg(struct pool *mem, struct volume_group *vg,
		       struct list *pvds, const char *dev_dir,
		       struct dev_filter *filter)
{
	struct list *pvh;
	struct pv_list *pvl;
	struct disk_list *data;

	list_iterate(pvh, &vg->pvs) {
		pvl = list_item(pvh, struct pv_list);

		if (!(data = _flatten_pv(mem, vg, pvl->pv, dev_dir))) {
			stack;
			return 0;
		}

		list_add(pvds, &data->list);
	}

	export_numbers(pvds, vg);
	export_pv_act(pvds);

	if (!export_vg_number(pvds, vg->name, filter)) {
		stack;
		return 0;
	}

	return 1;
}

static int _vg_write(struct format_instance *fi, struct volume_group *vg)
{
	struct pool *mem = pool_create(1024 * 10);
	struct list pvds;
	int r = 0;

	if (!mem) {
		stack;
		return 0;
	}

	if (vg->status & PARTIAL_VG) {
		log_error("Cannot change metadata for partial volume group %s",
			  vg->name);
		return 0;
	}

	list_init(&pvds);

	r = (_flatten_vg(mem, vg, &pvds, fi->cmd->dev_dir, fi->cmd->filter) &&
	     write_disks(&pvds));
	pool_destroy(mem);
	return r;
}

static struct physical_volume *_pv_read(struct format_instance *fi,
					const char *name)
{
	struct pool *mem = pool_create(1024);
	struct physical_volume *pv = NULL;
	struct disk_list *dl;
	struct device *dev;

        log_very_verbose("Reading physical volume data %s from disk", name);

	if (!mem) {
		stack;
		return NULL;
	}

	if (!(dev = dev_cache_get(name, fi->cmd->filter))) {
		stack;
		goto out;
	}

	if (!(dl = read_disk(dev, mem, NULL))) {
		stack;
		goto out;
	}

	if (!(pv = pool_alloc(fi->cmd->mem, sizeof(*pv)))) {
		stack;
		goto out;
	}

	if (!import_pv(fi->cmd->mem, dl->dev, NULL, pv, &dl->pvd)) {
		stack;
		pool_free(fi->cmd->mem, pv);
		pv = NULL;
	}

 out:
	pool_destroy(mem);
	return pv;
}

static struct list *_get_pvs(struct format_instance *fi)
{
	struct pool *mem = pool_create(1024 * 10);
	struct list pvs, *results;
	uint32_t count;

	if (!mem) {
		stack;
		return NULL;
	}

	if (!(results = pool_alloc(fi->cmd->mem, sizeof(*results)))) {
		stack;
		pool_destroy(mem);
		return NULL;
	}

	list_init(&pvs);
	list_init(results);

	if (!read_pvs_in_vg(NULL, fi->cmd->filter, mem, &pvs)) {
		stack;
		goto bad;
	}

	if (!import_pvs(fi->cmd->mem, NULL, &pvs, results, &count)) {
		stack;
		goto bad;
	}

	pool_destroy(mem);
	return results;

 bad:
	pool_free(fi->cmd->mem, results);
	pool_destroy(mem);
	return NULL;
}

static int _find_vg_name(struct list *names, const char *vg)
{
	struct list *nh;
	struct name_list *nl;

	list_iterate(nh, names) {
		nl = list_item(nh, struct name_list);
		if (!strcmp(nl->name, vg))
			return 1;
	}

	return 0;
}

static struct list *_get_vgs(struct format_instance *fi)
{
	struct list *pvh;
	struct list *pvs, *names = pool_alloc(fi->cmd->mem, sizeof(*names));
	struct name_list *nl;

	if (!names) {
		stack;
		return NULL;
	}

	list_init(names);

	if (!(pvs = _get_pvs(fi))) {
		stack;
		goto bad;
	}

	list_iterate(pvh, pvs) {
		struct pv_list *pvl = list_item(pvh, struct pv_list);

		if (!(*pvl->pv->vg_name) ||
	 	     _find_vg_name(names, pvl->pv->vg_name))
			continue;

		if (!(nl = pool_alloc(fi->cmd->mem, sizeof(*nl)))) {
			stack;
			goto bad;
		}

		if (!(nl->name = pool_strdup(fi->cmd->mem,
					     pvl->pv->vg_name))) {
			stack;
			goto bad;
		}

		list_add(names, &nl->list);
	}

	if (list_empty(names))
		goto bad;

	return names;

 bad:
	pool_free(fi->cmd->mem, names);
	return NULL;
}

static int _pv_setup(struct format_instance *fi, struct physical_volume *pv,
		     struct volume_group *vg)
{
	/* setup operations for the PV structure */
	if (pv->size > MAX_PV_SIZE)
		pv->size--;
	if (pv->size > MAX_PV_SIZE) {
		/* FIXME Limit hardcoded */
		log_error("Physical volumes cannot be bigger than 2TB");
		return 0;
	}

	/* Nothing more to do if pe_size isn't known */
	if (!vg) 
		return 1;

	/*
	 * This works out pe_start and pe_count.
	 */
	if (!calculate_extent_count(pv)) {
		stack;
		return 0;
	}

	return 1;
}

static int _find_free_lvnum(struct logical_volume *lv)
{
	int lvnum_used[MAX_LV];
	int i = 0;
	struct list *lvh;
	struct lv_list *lvl;

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

	list_iterate(lvh, &lv->vg->lvs) {
		lvl = list_item(lvh, struct lv_list);
		lvnum_used[lvnum_from_lvid(&lvl->lv->lvid)] = 1;
	}

	while (lvnum_used[i])
		i++;

	return i;
}

static int _lv_setup(struct format_instance *fi, struct logical_volume *lv)
{
	uint64_t max_size = UINT_MAX;

	lvid_from_lvnum(&lv->lvid, &lv->vg->id, _find_free_lvnum(lv));

	if (lv->le_count > MAX_LE_TOTAL) {
		log_error("logical volumes cannot contain more than "
			  "%d extents.", MAX_LE_TOTAL);
		return 0;
	}
	if (lv->size > max_size) {
                char *dummy = display_size(max_size, SIZE_SHORT);
		log_error("logical volumes cannot be larger than %s", dummy);
		dbg_free(dummy);
		return 0;
	}

	return 1;
}

static int _pv_write(struct format_instance *fi, struct physical_volume *pv)
{
	struct pool *mem;
	struct disk_list *dl;
	struct list pvs;

	list_init(&pvs);

	if (*pv->vg_name || pv->pe_allocated ) {
		log_error("Assertion failed: can't _pv_write non-orphan PV "
			  "(in VG %s)", pv->vg_name);
		return 0;
	}

	/* Ensure any residual PE structure is gone */
	pv->pe_size = pv->pe_count = pv->pe_start = 0;

	if (!(mem = pool_create(1024))) {
		stack;
		return 0;
	}

	if (!(dl = pool_alloc(mem, sizeof(*dl)))) {
		stack;
		goto bad;
	}
	dl->mem = mem;
	dl->dev = pv->dev;

	if (!export_pv(mem, NULL, &dl->pvd, pv)) {
		stack;
		goto bad;
	}

	/* must be set to be able to zero gap after PV structure in
	   dev_write in order to make other disk tools happy */
	dl->pvd.pv_on_disk.base = METADATA_BASE;
	dl->pvd.pv_on_disk.size = PV_SIZE;

	list_add(&pvs, &dl->list);
	if (!write_disks(&pvs)) {
		stack;
		goto bad;
	}

	pool_destroy(mem);
	return 1;

 bad:
	pool_destroy(mem);
	return 0;
}

int _vg_setup(struct format_instance *fi, struct volume_group *vg)
{
	/* just check max_pv and max_lv */
	if (vg->max_lv >= MAX_LV)
		vg->max_lv = MAX_LV - 1;

        if (vg->max_pv >= MAX_PV)
		vg->max_pv = MAX_PV - 1;

	if (vg->extent_size > MAX_PE_SIZE || vg->extent_size < MIN_PE_SIZE) {
		char *dummy, *dummy2;

		log_error("Extent size must be between %s and %s",
			(dummy = display_size(MIN_PE_SIZE / 2, SIZE_SHORT)),
			(dummy2 = display_size(MAX_PE_SIZE / 2, SIZE_SHORT)));

		dbg_free(dummy);
		dbg_free(dummy2);
		return 0;
	}

	if (vg->extent_size % MIN_PE_SIZE) {
		char *dummy;
		log_error("Extent size must be multiple of %s",
			(dummy = display_size(MIN_PE_SIZE / 2, SIZE_SHORT)));
		dbg_free(dummy);
		return 0;
	}

	/* Redundant? */
	if (vg->extent_size & (vg->extent_size - 1)) {
		log_error("Extent size must be power of 2");
		return 0;
	}

	return 1;
}

void _destroy(struct format_instance *fi)
{
	dbg_free(fi);
}


static struct format_handler _format1_ops = {
	get_vgs: _get_vgs,
	get_pvs: _get_pvs,
	pv_read: _pv_read,
	pv_setup: _pv_setup,
	pv_write: _pv_write,
	lv_setup: _lv_setup,
	vg_read: _vg_read,
	vg_setup: _vg_setup,
	vg_write: _vg_write,
	destroy: _destroy,
};

struct format_instance *create_lvm1_format(struct cmd_context *cmd)
{
	struct format_instance *fi = dbg_malloc(sizeof(*fi));

	if (!fi) {
		stack;
		return NULL;
	}

	fi->cmd = cmd;
	fi->ops = &_format1_ops;
	fi->private = NULL;

	return fi;
}