#include <linux/uaccess.h>
#include <linux/mm.h>
-void res_counter_init(struct res_counter *counter)
+void res_counter_init(struct res_counter *counter, struct res_counter *parent)
{
spin_lock_init(&counter->lock);
counter->limit = (unsigned long long)LLONG_MAX;
+ counter->parent = parent;
}
int res_counter_charge_locked(struct res_counter *counter, unsigned long val)
return 0;
}
-int res_counter_charge(struct res_counter *counter, unsigned long val)
+int res_counter_charge(struct res_counter *counter, unsigned long val,
+ struct res_counter **limit_fail_at)
{
int ret;
unsigned long flags;
-
- spin_lock_irqsave(&counter->lock, flags);
- ret = res_counter_charge_locked(counter, val);
- spin_unlock_irqrestore(&counter->lock, flags);
+ struct res_counter *c, *u;
+
+ *limit_fail_at = NULL;
+ local_irq_save(flags);
+ for (c = counter; c != NULL; c = c->parent) {
+ spin_lock(&c->lock);
+ ret = res_counter_charge_locked(c, val);
+ spin_unlock(&c->lock);
+ if (ret < 0) {
+ *limit_fail_at = c;
+ goto undo;
+ }
+ }
+ ret = 0;
+ goto done;
+undo:
+ for (u = counter; u != c; u = u->parent) {
+ spin_lock(&u->lock);
+ res_counter_uncharge_locked(u, val);
+ spin_unlock(&u->lock);
+ }
+done:
+ local_irq_restore(flags);
return ret;
}
void res_counter_uncharge(struct res_counter *counter, unsigned long val)
{
unsigned long flags;
+ struct res_counter *c;
- spin_lock_irqsave(&counter->lock, flags);
- res_counter_uncharge_locked(counter, val);
- spin_unlock_irqrestore(&counter->lock, flags);
+ local_irq_save(flags);
+ for (c = counter; c != NULL; c = c->parent) {
+ spin_lock(&c->lock);
+ res_counter_uncharge_locked(c, val);
+ spin_unlock(&c->lock);
+ }
+ local_irq_restore(flags);
}