+static minor_t next_minor = 0;
+static dtrace_state_t* dtrace_clients[DTRACE_NCLIENTS] = {NULL};
+
+
+minor_t
+dtrace_state_reserve(void)
+{
+ for (int i = 0; i < DTRACE_NCLIENTS; i++) {
+ minor_t minor = atomic_add_32(&next_minor, 1) % DTRACE_NCLIENTS;
+ if (dtrace_clients[minor] == NULL)
+ return minor;
+ }
+ return 0;
+}
+
+dtrace_state_t*
+dtrace_state_get(minor_t minor)
+{
+ ASSERT(minor < DTRACE_NCLIENTS);
+ return dtrace_clients[minor];
+}
+
+dtrace_state_t*
+dtrace_state_allocate(minor_t minor)
+{
+ dtrace_state_t *state = _MALLOC(sizeof(dtrace_state_t), M_TEMP, M_ZERO | M_WAITOK);
+ if (dtrace_casptr(&dtrace_clients[minor], NULL, state) != NULL) {
+ // We have been raced by another client for this number, abort
+ _FREE(state, M_TEMP);
+ return NULL;
+ }
+ return state;
+}
+
+void
+dtrace_state_free(minor_t minor)
+{
+ dtrace_state_t *state = dtrace_clients[minor];
+ dtrace_clients[minor] = NULL;
+ _FREE(state, M_TEMP);
+}