From 06d143d51f1a4adf1365c536ed2b5287e75325e8 Mon Sep 17 00:00:00 2001
From: Norman Feske <norman.feske@genode-labs.com>
Date: Wed, 13 May 2015 11:22:14 +0200
Subject: [PATCH] sel4: receive-sel handling for early IPC
---
repos/base-sel4/src/base/ipc/ipc.cc | 36 +++++++++++++++++++++++------
1 file changed, 29 insertions(+), 7 deletions(-)
diff --git a/repos/base-sel4/src/base/ipc/ipc.cc b/repos/base-sel4/src/base/ipc/ipc.cc
index 3390c3bd3a..b9e6212f69 100644
--- a/repos/base-sel4/src/base/ipc/ipc.cc
+++ b/repos/base-sel4/src/base/ipc/ipc.cc
@@ -38,6 +38,26 @@ enum {
};
+/**
+ * Return reference to receive selector of the calling thread
+ */
+static unsigned &rcv_sel()
+{
+ /*
+ * When the function is called at the very early initialization phase,
+ * we cannot access Thread_base::myself()->tid() because the Thread_base
+ * object of the main thread does not exist yet. During this phase, we
+ * return a reference to the 'main_rcv_sel' variable.
+ */
+ if (Thread_base::myself()) {
+ return Thread_base::myself()->tid().rcv_sel;
+ }
+
+ static unsigned main_rcv_sel = Capability_space::alloc_rcv_sel();
+ return main_rcv_sel;
+}
+
+
/**
* Convert Genode::Msgbuf_base content into seL4 message
*
@@ -77,10 +97,9 @@ static seL4_MessageInfo_t new_seL4_message(Msgbuf_base &msg,
/*
* Allocate and define receive selector
*/
- Native_thread &thread = Thread_base::myself()->tid();
- if (!thread.rcv_sel)
- thread.rcv_sel = Capability_space::alloc_rcv_sel();
+ if (!rcv_sel())
+ rcv_sel() = Capability_space::alloc_rcv_sel();
/*
* Supply data payload
@@ -174,7 +193,7 @@ static void decode_seL4_message(umword_t badge,
ASSERT(delegated);
- Native_thread &thread = Thread_base::myself()->tid();
+ ASSERT(delegated);
Native_capability arg_cap = Capability_space::lookup(rpc_obj_key);
@@ -189,14 +208,14 @@ static void decode_seL4_message(umword_t badge,
* Unfortunaltely, seL4 lacks such a comparison operation.
*/
- Capability_space::reset_sel(thread.rcv_sel);
+ Capability_space::reset_sel(rcv_sel());
dst_msg.append_cap(arg_cap);
} else {
Capability_space::Ipc_cap_data const
- ipc_cap_data(rpc_obj_key, thread.rcv_sel);
+ ipc_cap_data(rpc_obj_key, rcv_sel());
dst_msg.append_cap(Capability_space::import(ipc_cap_data));
@@ -204,7 +223,7 @@ static void decode_seL4_message(umword_t badge,
* Since we keep using the received selector, we need to
* allocate a fresh one for the next incoming delegation.
*/
- thread.rcv_sel = Capability_space::alloc_rcv_sel();
+ rcv_sel() = Capability_space::alloc_rcv_sel();
}
}
curr_sel4_cap_idx++;
@@ -295,6 +314,9 @@ void Ipc_client::_call()
kernel_debugger_panic("IPC destination is invalid");
}
+ if (!rcv_sel())
+ rcv_sel() = Capability_space::alloc_rcv_sel();
+
seL4_MessageInfo_t const request_msg_info =
new_seL4_message(*_snd_msg, _write_offset);