Bluetooth: Convert link keys list to use RCU
This patch converts the hdev->link_keys list to be protected through
RCU, thereby eliminating the need to hold the hdev lock while accessing
the list.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index a67a4b8..5c319a4 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -274,15 +274,13 @@
static int link_keys_show(struct seq_file *f, void *ptr)
{
struct hci_dev *hdev = f->private;
- struct list_head *p, *n;
+ struct link_key *key;
- hci_dev_lock(hdev);
- list_for_each_safe(p, n, &hdev->link_keys) {
- struct link_key *key = list_entry(p, struct link_key, list);
+ rcu_read_lock();
+ list_for_each_entry_rcu(key, &hdev->link_keys, list)
seq_printf(f, "%pMR %u %*phN %u\n", &key->bdaddr, key->type,
HCI_LINK_KEY_SIZE, key->val, key->pin_len);
- }
- hci_dev_unlock(hdev);
+ rcu_read_unlock();
return 0;
}
@@ -3101,15 +3099,11 @@
void hci_link_keys_clear(struct hci_dev *hdev)
{
- struct list_head *p, *n;
+ struct link_key *key;
- list_for_each_safe(p, n, &hdev->link_keys) {
- struct link_key *key;
-
- key = list_entry(p, struct link_key, list);
-
- list_del(p);
- kfree(key);
+ list_for_each_entry_rcu(key, &hdev->link_keys, list) {
+ list_del_rcu(&key->list);
+ kfree_rcu(key, rcu);
}
}
@@ -3137,9 +3131,14 @@
{
struct link_key *k;
- list_for_each_entry(k, &hdev->link_keys, list)
- if (bacmp(bdaddr, &k->bdaddr) == 0)
+ rcu_read_lock();
+ list_for_each_entry_rcu(k, &hdev->link_keys, list) {
+ if (bacmp(bdaddr, &k->bdaddr) == 0) {
+ rcu_read_unlock();
return k;
+ }
+ }
+ rcu_read_unlock();
return NULL;
}
@@ -3290,7 +3289,7 @@
key = kzalloc(sizeof(*key), GFP_KERNEL);
if (!key)
return NULL;
- list_add(&key->list, &hdev->link_keys);
+ list_add_rcu(&key->list, &hdev->link_keys);
}
BT_DBG("%s key for %pMR type %u", hdev->name, bdaddr, type);
@@ -3383,8 +3382,8 @@
BT_DBG("%s removing %pMR", hdev->name, bdaddr);
- list_del(&key->list);
- kfree(key);
+ list_del_rcu(&key->list);
+ kfree_rcu(key, rcu);
return 0;
}