Instead of mapping all physical memory 1:1 into core/kernel's address space,
this commit limits the 1:1 mapping to the binary image, and I/O memory
regions used by the kernel only. All subsequent memory accesses of core
are done by mapping the corresponding memory on demand, and not necessarily
1:1.
This commit has several side effects:
The page table code had to be revisited completely. The kernel inserts no
longer anything into the page tables, apart from the initial translations
to have the core/kernel image available when enabling the MMU. The page
tables and higher level translation tables are no longer named Tlb, but
Translation_table instead. There is no indirection class required to define
the translation tables of a concrete SoC, the appropriated ARM specifier
is sufficient.
The ability to map core's memory the same way like it's done for all other
protection domains, makes a special treatment of core's threads (no context
area) obsolete.
Ref #567 (partly solves it)
Fix#723Fix#1068
Kernel::resume_thread was restricted to core when the targeted thread was in
another domain. Now there are two kernel calls, resume_local_thread and
resume_thread, where the former is never restricted and is provided via
public kernel/interface.h and the latter is always restricted to core and
is provided via core-local kernel/core_interface.h.
ref #1101
Kernel::pause_current_thread can be implemented much simpler and is not
restricted to core threads, in contrast to Kernel::pause_thread which
also benefits from the split and can be moved to core_interface.h.
ref #1101
Previously this was not done before Thread_base::start(..) in
base-hw as it was not needed to have a valid cap that early. However,
when changing the affinity of a thread we need the cap to be valid
before Thread_base::start(..).
ref #1076
For a main thread a thread object is created by the CRT0 before _main gets
called so that _main can already run in a generic environment that, e.g.,
catches stack overflows as a page-fault instead of corrupting the BSS.
Additionally dynamic programs have only one CRT0 - the one of the LDSO -
which does the initialization for both LDSO and program.
ref #989
If an RM client gets dissolved the RM server tries to first
dissolve and then destruct the according pager object. As pager objects
previously cancelled unresolved faults only in destructor the dissolve
operation blocked forever when an unresolved fault existed.
As every pager object should get dissolved before it gets destructed
(signal-context complains otherwise) no more unresolved-fault cancelling
is needed in the destructor.
ref #989
Kernel::signal_context_kill can be used by any program to halt the processing
of a signal context synchronously to prevent broken refs when core destructs
the according kernel object. In turn, Kernel::bin_signal_context doesn't block
anymore and destructs a signal context no matter if there are unacknowledged
signals. This way, cores entrypoint doesn't depend on signal acks of a
untrustworthy client anymore.
ref #989
When using the initial SP of a main thread for the UTCB
startup-argument, fork_trampoline in libc_noux gets broken.
The function expects the SP to be initialized already in contrast
to the _start function in crt0.s that is called for processes that
are not forked. As the main-thread UTCB is located at the same virtual
address for every PD anyways, we can circumvent this problem by
defining it statically.
ref #964
Struct Msg was introduced due to the handling of pagefaults
and interrupts via synchronous IPC. Its only purpose was to provide
the message type in front of the typed message. Now pagefaults and
interrupts are handled via signals and struct Msg is not necessary
anymore.
ref #958
Every thread receives a startup message from its creator through the initial
state of its userland thread-context. The thread-startup code remembers the
kernel name of the new thread by reading this message before the userland
thread-context gets polluted. This way, Kernel::current_thread_id becomes
unnecessary.
fix#953
Enable routing of thread events to signal contexts via
Kernel::route_thread_event.
Replace Kernel::set_pager by Kernel::route_thread_event.
In base-hw a pager object is a signal context and a pager activation
is a signal receiver. If a thread wants to start communicating its page
faults via a pager object, the thread calls Kernel::route_thread_event with
its thread ID, event ID "FAULT", and the signal context ID of the pager object.
If a pager activation wants to start handling page faults of a pager object,
the pager activation assigns the corresponding signal context to its signal
receiver. If a pager activation wants to stop handling page faults of a pager
object, the pager activation dissolves the corresponding signal context from
its signal receiver. If a thread wants to start communicating its page faults
via a pager object, the thread calls Kernel::route_thread_event with its
thread ID, event ID "FAULT", and the invalid signal context ID.
Remove Kernel::resume_faulter.
Move all page fault related code from generic kernel sources to CPU
specific cpu_support.h and cpu_support.cc.
fix#935
By now Signal_session_component has allocated initial SLAB
blocks in constructor, wich crashed with the root
components assumptions about the RAM quota needs of
session creation. Thus, if the background allocator was already
exhausted from component allocation the session was created
with broken initial SLAB blocks.
fix#574
This patch eliminates calls of 'cmpxchg' prior enabling the MMU. This is
needed because the 'ldrex' and 'strex' instructions do not always work
with MMU and L1 cache disabled, i.e., on Raspberry Pi.
