提交 1e4f7bc8 编写于 作者: S Stefan Richter

ieee1394: nodemgr: remove a kcalloc

Was I sleepwalking when I wrote this?
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
上级 3015c739
......@@ -754,59 +754,33 @@ static DEFINE_MUTEX(nodemgr_serialize_remove_uds);
static void nodemgr_remove_uds(struct node_entry *ne)
{
struct class_device *cdev;
struct unit_directory *ud, **unreg;
size_t i, count;
struct unit_directory *tmp, *ud;
/*
* This is awkward:
* Iteration over nodemgr_ud_class.children has to be protected by
/* Iteration over nodemgr_ud_class.children has to be protected by
* nodemgr_ud_class.sem, but class_device_unregister() will eventually
* take nodemgr_ud_class.sem too. Therefore store all uds to be
* unregistered in a temporary array, release the semaphore, and then
* unregister the uds.
*
* Since nodemgr_remove_uds can also run in other contexts than the
* knodemgrds (which are currently globally serialized), protect the
* take nodemgr_ud_class.sem too. Therefore pick out one ud at a time,
* release the semaphore, and then unregister the ud. Since this code
* may be called from other contexts besides the knodemgrds, protect the
* gap after release of the semaphore by nodemgr_serialize_remove_uds.
*/
mutex_lock(&nodemgr_serialize_remove_uds);
down(&nodemgr_ud_class.sem);
count = 0;
list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
ud = container_of(cdev, struct unit_directory, class_dev);
if (ud->ne == ne)
count++;
}
if (!count) {
up(&nodemgr_ud_class.sem);
mutex_unlock(&nodemgr_serialize_remove_uds);
return;
}
unreg = kcalloc(count, sizeof(*unreg), GFP_KERNEL);
if (!unreg) {
HPSB_ERR("NodeMgr: out of memory in nodemgr_remove_uds");
up(&nodemgr_ud_class.sem);
mutex_unlock(&nodemgr_serialize_remove_uds);
return;
}
i = 0;
list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
ud = container_of(cdev, struct unit_directory, class_dev);
if (ud->ne == ne) {
BUG_ON(i >= count);
unreg[i++] = ud;
for (;;) {
ud = NULL;
down(&nodemgr_ud_class.sem);
list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
tmp = container_of(cdev, struct unit_directory,
class_dev);
if (tmp->ne == ne) {
ud = tmp;
break;
}
}
up(&nodemgr_ud_class.sem);
if (ud == NULL)
break;
class_device_unregister(&ud->class_dev);
device_unregister(&ud->device);
}
up(&nodemgr_ud_class.sem);
for (i = 0; i < count; i++) {
class_device_unregister(&unreg[i]->class_dev);
device_unregister(&unreg[i]->device);
}
kfree(unreg);
mutex_unlock(&nodemgr_serialize_remove_uds);
}
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册