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/*
* Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004 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 General Public License v.2.
*
* You should have received a copy of the GNU 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 "toolcontext.h"
#include "lv_alloc.h"
int lv_is_origin(const struct logical_volume *lv)
{
return lv->origin_count ? 1 : 0;
}
int lv_is_cow(const struct logical_volume *lv)
{
return lv->snapshot ? 1 : 0;
}
int lv_is_visible(const struct logical_volume *lv)
{
if (lv_is_cow(lv))
return lv_is_visible(find_cow(lv)->lv);
return lv->status & VISIBLE_LV ? 1 : 0;
}
/* Given a cow LV, return the snapshot lv_segment that uses it */
struct lv_segment *find_cow(const struct logical_volume *lv)
{
return lv->snapshot;
}
/* Given a cow LV, return its origin */
struct logical_volume *origin_from_cow(const struct logical_volume *lv)
{
return lv->snapshot->origin;
}
int vg_add_snapshot(struct format_instance *fid, const char *name,
struct logical_volume *origin,
struct logical_volume *cow, union lvid *lvid,
uint32_t extent_count, uint32_t chunk_size)
{
struct logical_volume *snap;
struct lv_segment *seg;
/*
* Is the cow device already being used ?
*/
if (lv_is_cow(cow)) {
log_err("'%s' is already in use as a snapshot.", cow->name);
return 0;
}
if (!(snap = lv_create_empty(fid, name ? name : "snapshot%d",
lvid, LVM_READ | LVM_WRITE | VISIBLE_LV,
ALLOC_INHERIT, 1, origin->vg))) {
stack;
return 0;
}
snap->le_count = extent_count;
if (!(seg = alloc_snapshot_seg(snap, 0, 0))) {
stack;
return 0;
}
seg->chunk_size = chunk_size;
seg->origin = origin;
seg->cow = cow;
seg->lv->status |= SNAPSHOT;
origin->origin_count++;
origin->vg->snapshot_count++;
origin->vg->lv_count--;
cow->snapshot = seg;
cow->status &= ~VISIBLE_LV;
list_add(&origin->snapshot_segs, &seg->origin_list);
return 1;
}
int vg_remove_snapshot(struct logical_volume *cow)
{
list_del(&cow->snapshot->origin_list);
cow->snapshot->origin->origin_count--;
if (!lv_remove(cow->snapshot->lv)) {
log_error("Failed to remove internal snapshot LV %s",
cow->snapshot->lv->name);
return 0;
}
cow->snapshot = NULL;
cow->vg->snapshot_count--;
cow->vg->lv_count++;
cow->status |= VISIBLE_LV;
return 1;
}
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