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/*
* Copyright (C) 2002 Sistina Software (UK) Limited.
*
* This file is released under the LGPL.
*/
#include "lib.h"
#include "metadata.h"
#include "toolcontext.h"
int lv_is_origin(const struct logical_volume *lv)
{
struct list *slh;
struct snapshot *s;
list_iterate(slh, &lv->vg->snapshots) {
s = list_item(slh, struct snapshot_list)->snapshot;
if (s->origin == lv)
return 1;
}
return 0;
}
int lv_is_cow(const struct logical_volume *lv)
{
struct list *slh;
struct snapshot *s;
list_iterate(slh, &lv->vg->snapshots) {
s = list_item(slh, struct snapshot_list)->snapshot;
if (s->cow == lv)
return 1;
}
return 0;
}
struct snapshot *find_origin(const struct logical_volume *lv)
{
struct list *slh;
struct snapshot *s;
list_iterate(slh, &lv->vg->snapshots) {
s = list_item(slh, struct snapshot_list)->snapshot;
if (s->origin == lv)
return s;
}
return NULL;
}
struct snapshot *find_cow(const struct logical_volume *lv)
{
struct list *slh;
struct snapshot *s;
list_iterate(slh, &lv->vg->snapshots) {
s = list_item(slh, struct snapshot_list)->snapshot;
if (s->cow == lv)
return s;
}
return NULL;
}
struct list *find_snapshots(const struct logical_volume *lv)
{
struct list *slh;
struct list *snaplist;
struct snapshot *s;
struct snapshot_list *newsl;
struct pool *mem = lv->vg->cmd->mem;
if (!(snaplist = pool_alloc(mem, sizeof(*snaplist)))) {
log_error("snapshot name list allocation failed");
return NULL;
}
list_init(snaplist);
list_iterate(slh, &lv->vg->snapshots) {
s = list_item(slh, struct snapshot_list)->snapshot;
if (!(s->origin == lv))
continue;
if (!(newsl = pool_alloc(mem, sizeof(*newsl)))) {
log_error("snapshot_list structure allocation failed");
pool_free(mem, snaplist);
return NULL;
}
newsl->snapshot = s;
list_add(snaplist, &newsl->list);
}
return snaplist;
}
int vg_add_snapshot(struct logical_volume *origin,
struct logical_volume *cow,
int persistent, struct id *id, uint32_t chunk_size)
{
struct snapshot *s;
struct snapshot_list *sl;
struct pool *mem = origin->vg->cmd->mem;
/*
* 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 (!(s = pool_alloc(mem, sizeof(*s)))) {
stack;
return 0;
}
s->persistent = persistent;
s->chunk_size = chunk_size;
s->origin = origin;
s->cow = cow;
if (id)
s->id = *id;
else if (!id_create(&s->id)) {
log_error("Snapshot UUID creation failed");
return 0;
}
if (!(sl = pool_alloc(mem, sizeof(*sl)))) {
stack;
pool_free(mem, s);
return 0;
}
cow->status &= ~VISIBLE_LV;
sl->snapshot = s;
list_add(&origin->vg->snapshots, &sl->list);
origin->vg->snapshot_count++;
return 1;
}
int vg_remove_snapshot(struct volume_group *vg, struct logical_volume *cow)
{
struct list *slh;
struct snapshot_list *sl;
list_iterate(slh, &vg->snapshots) {
sl = list_item(slh, struct snapshot_list);
if (sl->snapshot->cow == cow) {
list_del(slh);
vg->snapshot_count--;
return 1;
}
}
/* fail */
log_err("Asked to remove an unknown snapshot.");
return 0;
}
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