/*
* _determine_cache_argument
* @vg
* @lp
*
* 'lp->origin' is set with an LV that could be either the origin
* or the cache_pool of the cached LV which is being created. This
* function determines which it is and sets 'lp->origin' or
* 'lp->pool' appropriately.
*/
static int _determine_cache_argument(struct volume_group *vg,
struct lvcreate_params *lp)
{
struct lv_list *lvl;
if (!seg_is_cache(lp)) {
log_error(INTERNAL_ERROR
"Unable to determine cache argument on %s segtype",
lp->segtype->name);
return 0;
}
if (!lp->origin) {
log_error(INTERNAL_ERROR "Origin LV is not defined.");
return 0;
}
if (!(lvl = find_lv_in_vg(vg, lp->origin))) {
log_error("LV %s not found in Volume group %s.",
lp->origin, vg->name);
return 0;
}
if (lv_is_cache_pool(lvl->lv)) {
lp->pool = lp->origin;
lp->origin = NULL;
} else {
lp->pool = NULL;
lp->create_pool = 1;
}
return 1;
}
/*
* lv_cache_create
* @pool
* @origin
*
* Given a cache_pool and an origin, link the two and create a
* cached LV.
*
* Returns: cache LV on success, NULL on failure
*/
struct logical_volume *lv_cache_create(struct logical_volume *pool,
struct logical_volume *origin)
{
const struct segment_type *segtype;
struct cmd_context *cmd = pool->vg->cmd;
struct logical_volume *cache_lv;
struct lv_segment *seg;
if (!lv_is_cache_pool(pool)) {
log_error(INTERNAL_ERROR
"%s is not a cache_pool LV", pool->name);
return NULL;
}
if (!dm_list_empty(&pool->segs_using_this_lv)) {
seg = get_only_segment_using_this_lv(pool);
log_error("%s is already in use by %s",
pool->name, seg ? seg->lv->name : "another LV");
return NULL;
}
if (lv_is_cache_type(origin)) {
/*
* FIXME: We can layer caches, insert_layer_for_lv() would
* have to do a better job renaming the LVs in the stack
* first so that there isn't a name collision with <name>_corig.
* The origin under the origin would become *_corig_corig
* before renaming the origin above to *_corig.
*/
log_error(INTERNAL_ERROR
"The origin, %s, cannot be of cache type",
origin->name);
return NULL;
}
if (!(segtype = get_segtype_from_string(cmd, "cache")))
return_NULL;
cache_lv = origin;
if (!(origin = insert_layer_for_lv(cmd, cache_lv, CACHE, "_corig")))
return_NULL;
seg = first_seg(cache_lv);
seg->segtype = segtype;
if (!attach_pool_lv(seg, pool, NULL, NULL))
return_NULL;
return cache_lv;
}
static dm_percent_t _metadata_percent(const struct logical_volume *lv)
{
dm_percent_t percent;
struct lv_status_cache *status;
if (lv_is_cache(lv) || lv_is_cache_pool(lv)) {
if (!lv_cache_status(lv, &status)) {
stack;
return DM_PERCENT_INVALID;
}
percent = status->dirty_usage;
dm_pool_destroy(status->mem);
return percent;
}
if (lv_is_thin_pool(lv))
return lv_thin_pool_percent(lv, 1, &percent) ? percent : DM_PERCENT_INVALID;
return DM_PERCENT_INVALID;
}
