in label.c [1057:1289]
static int __blk_label_update(struct nd_region *nd_region,
struct nd_mapping *nd_mapping, struct nd_namespace_blk *nsblk,
int num_labels)
{
int i, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
struct nd_interleave_set *nd_set = nd_region->nd_set;
struct nd_namespace_common *ndns = &nsblk->common;
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
struct nd_namespace_label *nd_label;
struct nd_label_ent *label_ent, *e;
struct nd_namespace_index *nsindex;
unsigned long *free, *victim_map = NULL;
struct resource *res, **old_res_list;
struct nd_label_id label_id;
int min_dpa_idx = 0;
LIST_HEAD(list);
u32 nslot, slot;
if (!preamble_next(ndd, &nsindex, &free, &nslot))
return -ENXIO;
old_res_list = nsblk->res;
nfree = nd_label_nfree(ndd);
old_num_resources = nsblk->num_resources;
nd_label_gen_id(&label_id, nsblk->uuid, NSLABEL_FLAG_LOCAL);
/*
* We need to loop over the old resources a few times, which seems a
* bit inefficient, but we need to know that we have the label
* space before we start mutating the tracking structures.
* Otherwise the recovery method of last resort for userspace is
* disable and re-enable the parent region.
*/
alloc = 0;
for_each_dpa_resource(ndd, res) {
if (strcmp(res->name, label_id.id) != 0)
continue;
if (!is_old_resource(res, old_res_list, old_num_resources))
alloc++;
}
victims = 0;
if (old_num_resources) {
/* convert old local-label-map to dimm-slot victim-map */
victim_map = bitmap_zalloc(nslot, GFP_KERNEL);
if (!victim_map)
return -ENOMEM;
/* mark unused labels for garbage collection */
for_each_clear_bit_le(slot, free, nslot) {
nd_label = to_label(ndd, slot);
if (!nsl_uuid_equal(ndd, nd_label, nsblk->uuid))
continue;
res = to_resource(ndd, nd_label);
if (res && is_old_resource(res, old_res_list,
old_num_resources))
continue;
slot = to_slot(ndd, nd_label);
set_bit(slot, victim_map);
victims++;
}
}
/* don't allow updates that consume the last label */
if (nfree - alloc < 0 || nfree - alloc + victims < 1) {
dev_info(&nsblk->common.dev, "insufficient label space\n");
bitmap_free(victim_map);
return -ENOSPC;
}
/* from here on we need to abort on error */
/* assign all resources to the namespace before writing the labels */
nsblk->res = NULL;
nsblk->num_resources = 0;
for_each_dpa_resource(ndd, res) {
if (strcmp(res->name, label_id.id) != 0)
continue;
if (!nsblk_add_resource(nd_region, ndd, nsblk, res->start)) {
rc = -ENOMEM;
goto abort;
}
}
/* release slots associated with any invalidated UUIDs */
mutex_lock(&nd_mapping->lock);
list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list)
if (test_and_clear_bit(ND_LABEL_REAP, &label_ent->flags)) {
reap_victim(nd_mapping, label_ent);
list_move(&label_ent->list, &list);
}
mutex_unlock(&nd_mapping->lock);
/*
* Find the resource associated with the first label in the set
* per the v1.2 namespace specification.
*/
for (i = 0; i < nsblk->num_resources; i++) {
struct resource *min = nsblk->res[min_dpa_idx];
res = nsblk->res[i];
if (res->start < min->start)
min_dpa_idx = i;
}
for (i = 0; i < nsblk->num_resources; i++) {
size_t offset;
res = nsblk->res[i];
if (is_old_resource(res, old_res_list, old_num_resources))
continue; /* carry-over */
slot = nd_label_alloc_slot(ndd);
if (slot == UINT_MAX) {
rc = -ENXIO;
goto abort;
}
dev_dbg(ndd->dev, "allocated: %d\n", slot);
nd_label = to_label(ndd, slot);
memset(nd_label, 0, sizeof_namespace_label(ndd));
nsl_set_uuid(ndd, nd_label, nsblk->uuid);
nsl_set_name(ndd, nd_label, nsblk->alt_name);
nsl_set_flags(ndd, nd_label, NSLABEL_FLAG_LOCAL);
nsl_set_blk_nlabel(ndd, nd_label, nsblk->num_resources,
i == min_dpa_idx);
nsl_set_blk_position(ndd, nd_label, i == min_dpa_idx);
nsl_set_blk_isetcookie(ndd, nd_label, nd_set->cookie2);
nsl_set_dpa(ndd, nd_label, res->start);
nsl_set_rawsize(ndd, nd_label, resource_size(res));
nsl_set_lbasize(ndd, nd_label, nsblk->lbasize);
nsl_set_slot(ndd, nd_label, slot);
nsl_set_type_guid(ndd, nd_label, &nd_set->type_guid);
nsl_set_claim_class(ndd, nd_label, ndns->claim_class);
nsl_calculate_checksum(ndd, nd_label);
/* update label */
offset = nd_label_offset(ndd, nd_label);
rc = nvdimm_set_config_data(ndd, offset, nd_label,
sizeof_namespace_label(ndd));
if (rc < 0)
goto abort;
}
/* free up now unused slots in the new index */
for_each_set_bit(slot, victim_map, victim_map ? nslot : 0) {
dev_dbg(ndd->dev, "free: %d\n", slot);
nd_label_free_slot(ndd, slot);
}
/* update index */
rc = nd_label_write_index(ndd, ndd->ns_next,
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
if (rc)
goto abort;
/*
* Now that the on-dimm labels are up to date, fix up the tracking
* entries in nd_mapping->labels
*/
nlabel = 0;
mutex_lock(&nd_mapping->lock);
list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
nd_label = label_ent->label;
if (!nd_label)
continue;
nlabel++;
if (!nsl_uuid_equal(ndd, nd_label, nsblk->uuid))
continue;
nlabel--;
list_move(&label_ent->list, &list);
label_ent->label = NULL;
}
list_splice_tail_init(&list, &nd_mapping->labels);
mutex_unlock(&nd_mapping->lock);
if (nlabel + nsblk->num_resources > num_labels) {
/*
* Bug, we can't end up with more resources than
* available labels
*/
WARN_ON_ONCE(1);
rc = -ENXIO;
goto out;
}
mutex_lock(&nd_mapping->lock);
label_ent = list_first_entry_or_null(&nd_mapping->labels,
typeof(*label_ent), list);
if (!label_ent) {
WARN_ON(1);
mutex_unlock(&nd_mapping->lock);
rc = -ENXIO;
goto out;
}
for_each_clear_bit_le(slot, free, nslot) {
nd_label = to_label(ndd, slot);
if (!nsl_uuid_equal(ndd, nd_label, nsblk->uuid))
continue;
res = to_resource(ndd, nd_label);
res->flags &= ~DPA_RESOURCE_ADJUSTED;
dev_vdbg(&nsblk->common.dev, "assign label slot: %d\n", slot);
list_for_each_entry_from(label_ent, &nd_mapping->labels, list) {
if (label_ent->label)
continue;
label_ent->label = nd_label;
nd_label = NULL;
break;
}
if (nd_label)
dev_WARN(&nsblk->common.dev,
"failed to track label slot%d\n", slot);
}
mutex_unlock(&nd_mapping->lock);
out:
kfree(old_res_list);
bitmap_free(victim_map);
return rc;
abort:
/*
* 1/ repair the allocated label bitmap in the index
* 2/ restore the resource list
*/
nd_label_copy(ndd, nsindex, to_current_namespace_index(ndd));
kfree(nsblk->res);
nsblk->res = old_res_list;
nsblk->num_resources = old_num_resources;
old_res_list = NULL;
goto out;
}