WebSVN – HelenOS – Diff – /branches/tracing/kernel/generic/src/ipc/sysipc.c

  *          Otherwise return 0.
  */
 static inline int method_is_forwardable(unative_t method)
+{
     switch (method) {
+    case IPC_M_CONNECTION_CLONE:
+    case IPC_M_CONNECT_ME:
     case IPC_M_PHONE_HUNGUP:
         /* This message is meant only for the original recipient. */
         return 0;
     default:
         return 1;
  *          Return 0 otherwise.
  */
 static inline int answer_need_old(call_t *call)
+{
     switch (IPC_GET_METHOD(call->data)) {
+    case IPC_M_CONNECTION_CLONE:
+    case IPC_M_CONNECT_ME:
     case IPC_M_CONNECT_TO_ME:
     case IPC_M_CONNECT_ME_TO:
     case IPC_M_SHARE_OUT:
     case IPC_M_SHARE_IN:
     case IPC_M_DATA_WRITE:
+    }
     if (!olddata)
         return 0;
+    if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECTION_CLONE) {
+        phoneid = IPC_GET_ARG1(*olddata);
+        phone_t *phone = &TASK->phones[phoneid];
+        if (IPC_GET_RETVAL(answer->data) != EOK) {
+            /*
+             * The recipient of the cloned phone rejected the offer.
+             * In this case, the connection was established at the
+             * request time and therefore we need to slam the phone.
+             * We don't merely hangup as that would result in
+             * sending IPC_M_HUNGUP to the third party on the
+             * other side of the cloned phone.
+             */
+            mutex_lock(&phone->lock);
+            if (phone->state == IPC_PHONE_CONNECTED) {
+                spinlock_lock(&phone->callee->lock);
+                list_remove(&phone->link);
+                phone->state = IPC_PHONE_SLAMMED;
+                spinlock_unlock(&phone->callee->lock);
+            }
+            mutex_unlock(&phone->lock);
+        }
+    } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME) {
+        phone_t *phone = (phone_t *)IPC_GET_ARG5(*olddata);
+        if (IPC_GET_RETVAL(answer->data) != EOK) {
+            /*
+             * The other party on the cloned phoned rejected our
+             * request for connection on the protocol level.
+             * We need to break the connection without sending
+             * IPC_M_HUNGUP back.
+             */
+            mutex_lock(&phone->lock);
+            if (phone->state == IPC_PHONE_CONNECTED) {
+                spinlock_lock(&phone->callee->lock);
+                list_remove(&phone->link);
+                phone->state = IPC_PHONE_SLAMMED;
+                spinlock_unlock(&phone->callee->lock);
+            }
+            mutex_unlock(&phone->lock);
+        }
-    if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_TO_ME) {
+    } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_TO_ME) {
         phoneid = IPC_GET_ARG5(*olddata);
-        if (IPC_GET_RETVAL(answer->data)) {
+        if (IPC_GET_RETVAL(answer->data) != EOK) {
             /* The connection was not accepted */
             phone_dealloc(phoneid);
         } else {
             /* The connection was accepted */
             phone_connect(phoneid, &answer->sender->answerbox);
             IPC_SET_ARG5(answer->data,
                 (unative_t) &TASK->phones[phoneid]);
+        }
     } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME_TO) {
         /* If the users accepted call, connect */
-        if (!IPC_GET_RETVAL(answer->data)) {
+        if (IPC_GET_RETVAL(answer->data) == EOK) {
             ipc_phone_connect((phone_t *) IPC_GET_ARG5(*olddata),
                 &TASK->answerbox);
+        }
     } else if (IPC_GET_METHOD(*olddata) == IPC_M_SHARE_OUT) {
         if (!IPC_GET_RETVAL(answer->data)) {
         answer->buffer = NULL;
+    }
     return 0;
+}
+static void phones_lock(phone_t *p1, phone_t *p2)
+{
+    if (p1 < p2) {
+        mutex_lock(&p1->lock);
+        mutex_lock(&p2->lock);
+    } else if (p1 > p2) {
+        mutex_lock(&p2->lock);
+        mutex_lock(&p1->lock);
+    } else {
+        mutex_lock(&p1->lock);
+    }
+}
+static void phones_unlock(phone_t *p1, phone_t *p2)
+{
+    mutex_unlock(&p1->lock);
+    if (p1 != p2)
+        mutex_unlock(&p2->lock);
+}
 /** Called before the request is sent.
+ *
  * @param call      Call structure with the request.
  * @param phone     Phone that the call will be sent through.
+ *
     size_t size;
     uintptr_t src;
     int rc;
     switch (IPC_GET_METHOD(call->data)) {
+    case IPC_M_CONNECTION_CLONE: {
+        phone_t *cloned_phone;
+        GET_CHECK_PHONE(cloned_phone, IPC_GET_ARG1(call->data),
+            return ENOENT);
+        phones_lock(cloned_phone, phone);
+        if ((cloned_phone->state != IPC_PHONE_CONNECTED) ||
+            phone->state != IPC_PHONE_CONNECTED) {
+            phones_unlock(cloned_phone, phone);
+            return EINVAL;
+        }
+        /*
+         * We can be pretty sure now that both tasks exist and we are
+         * connected to them. As we continue to hold the phone locks,
+         * we are effectively preventing them from finishing their
+         * potential cleanup.
+         */
+        newphid = phone_alloc(phone->callee->task);
+        if (newphid < 0) {
+            phones_unlock(cloned_phone, phone);
+            return ELIMIT;
+        }
+        ipc_phone_connect(&phone->callee->task->phones[newphid],
+            cloned_phone->callee);
+        phones_unlock(cloned_phone, phone);
+        /* Set the new phone for the callee. */
+        IPC_SET_ARG1(call->data, newphid);
+        break;
+    }
+    case IPC_M_CONNECT_ME:
+        IPC_SET_ARG5(call->data, (unative_t) phone);
+        break;
     case IPC_M_CONNECT_ME_TO:
-        newphid = phone_alloc();
+        newphid = phone_alloc(TASK);
         if (newphid < 0)
             return ELIMIT;
         /* Set arg5 for server */
         IPC_SET_ARG5(call->data, (unative_t) &TASK->phones[newphid]);
         call->flags |= IPC_CALL_CONN_ME_TO;
 static int process_request(answerbox_t *box, call_t *call)
+{
     int phoneid;
     if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME) {
-        phoneid = phone_alloc();
+        phoneid = phone_alloc(TASK);
         if (phoneid < 0) { /* Failed to allocate phone */
             IPC_SET_RETVAL(call->data, ELIMIT);
             ipc_answer(box, call);
             return -1;
+        }

Subversion Repositories HelenOS

(root)/branches/tracing/kernel/generic/src/ipc/sysipc.c @ 4509 – Rev 4377 → 4692