libnvdimm, label: convert label tracking to a linked list
In preparation for enabling multiple namespaces per pmem region, convert
the label tracking to use a linked list. In particular this will allow
select_pmem_id() to move labels from the unvalidated state to the
validated state. Currently we only track one validated set per-region.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 96526dc..c373572 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -499,6 +499,7 @@
struct nd_namespace_label *victim_label;
struct nd_namespace_label *nd_label;
struct nd_namespace_index *nsindex;
+ struct nd_label_ent *label_ent;
unsigned long *free;
u32 nslot, slot;
size_t offset;
@@ -536,8 +537,13 @@
return rc;
/* Garbage collect the previous label */
- victim_label = nd_mapping->labels[0];
+ mutex_lock(&nd_mapping->lock);
+ label_ent = list_first_entry_or_null(&nd_mapping->labels,
+ typeof(*label_ent), list);
+ WARN_ON(!label_ent);
+ victim_label = label_ent ? label_ent->label : NULL;
if (victim_label) {
+ label_ent->label = NULL;
slot = to_slot(ndd, victim_label);
nd_label_free_slot(ndd, slot);
dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
@@ -546,28 +552,11 @@
/* update index */
rc = nd_label_write_index(ndd, ndd->ns_next,
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
- if (rc < 0)
- return rc;
+ if (rc == 0 && label_ent)
+ label_ent->label = nd_label;
+ mutex_unlock(&nd_mapping->lock);
- nd_mapping->labels[0] = nd_label;
-
- return 0;
-}
-
-static void del_label(struct nd_mapping *nd_mapping, int l)
-{
- struct nd_namespace_label *next_label, *nd_label;
- struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
- unsigned int slot;
- int j;
-
- nd_label = nd_mapping->labels[l];
- slot = to_slot(ndd, nd_label);
- dev_vdbg(ndd->dev, "%s: clear: %d\n", __func__, slot);
-
- for (j = l; (next_label = nd_mapping->labels[j + 1]); j++)
- nd_mapping->labels[j] = next_label;
- nd_mapping->labels[j] = NULL;
+ return rc;
}
static bool is_old_resource(struct resource *res, struct resource **list, int n)
@@ -607,14 +596,16 @@
struct nd_mapping *nd_mapping, struct nd_namespace_blk *nsblk,
int num_labels)
{
- int i, l, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
+ int i, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
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;
u8 uuid[NSLABEL_UUID_LEN];
+ LIST_HEAD(list);
u32 nslot, slot;
if (!preamble_next(ndd, &nsindex, &free, &nslot))
@@ -736,15 +727,22 @@
* entries in nd_mapping->labels
*/
nlabel = 0;
- for_each_label(l, nd_label, nd_mapping->labels) {
+ 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++;
memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
continue;
nlabel--;
- del_label(nd_mapping, l);
- l--; /* retry with the new label at this index */
+ 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
@@ -755,6 +753,15 @@
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 = nd_label_base(ndd) + slot;
memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
@@ -762,11 +769,19 @@
continue;
res = to_resource(ndd, nd_label);
res->flags &= ~DPA_RESOURCE_ADJUSTED;
- dev_vdbg(&nsblk->common.dev, "assign label[%d] slot: %d\n",
- l, slot);
- nd_mapping->labels[l++] = nd_label;
+ 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);
}
- nd_mapping->labels[l] = NULL;
+ mutex_unlock(&nd_mapping->lock);
out:
kfree(old_res_list);
@@ -788,32 +803,28 @@
static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
{
- int i, l, old_num_labels = 0;
+ int i, old_num_labels = 0;
+ struct nd_label_ent *label_ent;
struct nd_namespace_index *nsindex;
- struct nd_namespace_label *nd_label;
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
- size_t size = (num_labels + 1) * sizeof(struct nd_namespace_label *);
- for_each_label(l, nd_label, nd_mapping->labels)
+ mutex_lock(&nd_mapping->lock);
+ list_for_each_entry(label_ent, &nd_mapping->labels, list)
old_num_labels++;
+ mutex_unlock(&nd_mapping->lock);
/*
* We need to preserve all the old labels for the mapping so
* they can be garbage collected after writing the new labels.
*/
- if (num_labels > old_num_labels) {
- struct nd_namespace_label **labels;
-
- labels = krealloc(nd_mapping->labels, size, GFP_KERNEL);
- if (!labels)
+ for (i = old_num_labels; i < num_labels; i++) {
+ label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
+ if (!label_ent)
return -ENOMEM;
- nd_mapping->labels = labels;
+ mutex_lock(&nd_mapping->lock);
+ list_add_tail(&label_ent->list, &nd_mapping->labels);
+ mutex_unlock(&nd_mapping->lock);
}
- if (!nd_mapping->labels)
- return -ENOMEM;
-
- for (i = old_num_labels; i <= num_labels; i++)
- nd_mapping->labels[i] = NULL;
if (ndd->ns_current == -1 || ndd->ns_next == -1)
/* pass */;
@@ -837,42 +848,45 @@
static int del_labels(struct nd_mapping *nd_mapping, u8 *uuid)
{
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;
u8 label_uuid[NSLABEL_UUID_LEN];
- int l, num_freed = 0;
unsigned long *free;
+ LIST_HEAD(list);
u32 nslot, slot;
+ int active = 0;
if (!uuid)
return 0;
/* no index || no labels == nothing to delete */
- if (!preamble_next(ndd, &nsindex, &free, &nslot)
- || !nd_mapping->labels)
+ if (!preamble_next(ndd, &nsindex, &free, &nslot))
return 0;
- for_each_label(l, nd_label, nd_mapping->labels) {
+ mutex_lock(&nd_mapping->lock);
+ list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
+ struct nd_namespace_label *nd_label = label_ent->label;
+
+ if (!nd_label)
+ continue;
+ active++;
memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
if (memcmp(label_uuid, uuid, NSLABEL_UUID_LEN) != 0)
continue;
+ active--;
slot = to_slot(ndd, nd_label);
nd_label_free_slot(ndd, slot);
dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot);
- del_label(nd_mapping, l);
- num_freed++;
- l--; /* retry with new label at this index */
+ list_move_tail(&label_ent->list, &list);
+ label_ent->label = NULL;
}
+ list_splice_tail_init(&list, &nd_mapping->labels);
- if (num_freed > l) {
- /*
- * num_freed will only ever be > l when we delete the last
- * label
- */
- kfree(nd_mapping->labels);
- nd_mapping->labels = NULL;
- dev_dbg(ndd->dev, "%s: no more labels\n", __func__);
+ if (active == 0) {
+ nd_mapping_free_labels(nd_mapping);
+ dev_dbg(ndd->dev, "%s: no more active labels\n", __func__);
}
+ mutex_unlock(&nd_mapping->lock);
return nd_label_write_index(ndd, ndd->ns_next,
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);