#pypp 0
// Iris: micro-kernel for a capability-based operating system.
// kernel.hhp: Header for all kernel sources.
// Copyright 2009 Bas Wijnen <wijnen@debian.org>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

#ifndef _KERNEL_HH
#define _KERNEL_HH

// Number of clock interrupts per second.
#define HZ 10

// Include definitions which are shared with user space.
#define __KERNEL
#include "iris.h"

// Normally define all variables in this file as extern.
// Exactly once (in data.ccp), EXTERN is predefined empty.
// That results in space being allocated in its object file.
#ifndef EXTERN
#define EXTERN extern
#endif

// Without the standard library, we don't have this definition.
// I preferred ((void*)0), but C++ has too strict type-checking to
// make that work.
#define NULL 0

struct Object_base
struct Page
struct Thread
struct Message
struct Receiver
struct Capability
struct Cappage
struct Memory

struct Object_base:
	Capability *refs
	Memory *address_space
	inline bool is_free ()

template <typename _T> //
struct Object : public Object_base:
	// Next and previous object of the same type in any page.
	_T *prev, *next

struct Free : public Object <Free>:
	// This marker is ~0.  No other kernel structure may allow this value
	// at this point.  It is used to recognize free chunks.
	unsigned marker

bool Object_base::is_free ():
	return ((Free *)this)->marker == ~0

// Include architecture-specific parts.
#include "arch.hh"

struct Thread : public Object <Thread>:
	Receiver *receivers
	unsigned pc, sp
	Thread_arch arch
	unsigned flags
	unsigned sleep
	Thread *schedule_prev, *schedule_next
	void run ()
	void unrun ()
	void wait ()
	void unwait ()
	bool is_waiting ():
		return flags & THREAD_FLAG_WAITING

struct Message : public Object <Message>:
	Capability *capabilities[4]
	unsigned data[4]
	unsigned protected_data

struct Capability : public Object <Capability>:
	struct Context:
		unsigned data[4]
		Capability *cap[4]
		bool copy[4]
	Receiver *target
	Capability *parent
	Capability *children
	Capability *sibling_prev, *sibling_next
	unsigned protected_data
	bool invoke (Context *c)
	void invalidate ()

struct Receiver : public Object <Receiver>:
	Thread *owner
	Receiver *prev_owned, *next_owned
	Capability *capabilities
	Message *messages
	unsigned reply_protected_data
	bool protected_only
	void own (Thread *o)
	void orphan ()
	bool try_deliver ()
	bool send_message (unsigned protected_data, Capability::Context *c)

struct ShareData :
	unsigned frame
	unsigned flags
	void *share_first
	void *share_prev, *share_next

struct Page : public Object <Page>:
	ShareData data
	Page_arch arch
	void forget ()

struct Cappage : public Object <Cappage>:
	ShareData data
	void forget ()

struct Memory : public Object <Memory>:
	Free *frees
	Page *pages
	Thread *threads
	Receiver *receivers
	Capability *capabilities
	Cappage *cappages
	Memory *memories
	unsigned limit, used
	Memory_arch arch

	inline bool map (Page *page, unsigned address, bool write)
	inline void unmap (Page *page, unsigned address)
	inline Page *get_mapping (unsigned address, bool *writable)

	// Allocation of pages.
	bool use ()
	void unuse ()
	unsigned palloc ()
	unsigned zalloc ()
	void pfree (unsigned page)
	void zfree (unsigned page)

	// Allocation routines for kernel structures
	void *search_free (unsigned size, void **first)
	Page *alloc_page ()
	Thread *alloc_thread ()
	Message *alloc_message (Receiver *target, unsigned protected_data)
	Receiver *alloc_receiver ()
	Capability *alloc_capability (Receiver *target, Capability *parent, Capability **parent_ptr, unsigned protected_data, Capability *ret = NULL)
	Capability *clone_capability (Capability *source, bool copy, Capability *ret = NULL)
	Cappage *alloc_cappage ()
	Memory *alloc_memory ()

	void free_page (Page *page)
	void free_thread (Thread *thread)
	void free_message (Message *message)
	void free_receiver (Receiver *receiver)
	void free_capability (Capability *capability)
	void free_cappage (Cappage *page)
	void free_memory (Memory *mem)

	void free_obj (Object_base *obj)

	Capability *find_capability (unsigned code, bool *copy)

// Functions which can be called from assembly must not be mangled.
extern "C":
	// Panic.  n is sent over caps led.  message is currently ignored.
	void panic (unsigned n, char const *message = "")
	// Debug: switch caps led
	void dbg_led (bool one, bool two, bool three)
	void dbg_sleep (unsigned ms)
	void dbg_send (unsigned code, unsigned bits = 32)

/// Defined in schedule.ccp
void schedule ()
void timer_interrupt ()

struct FreePage:
	FreePage *next

EXTERN FreePage *zero_pages, *junk_pages
EXTERN Memory top_memory
EXTERN Thread *sleepers, *runners
EXTERN Thread idle
EXTERN Memory idle_memory
EXTERN Page idle_page
EXTERN Thread *first_scheduled, *first_sleeper
EXTERN Thread *current

// Defined in alloc.cc
unsigned raw_zalloc ()
void raw_pfree (unsigned page)

// Defined by architecture-specific files.
void Thread_arch_init (Thread *thread)
void Thread_arch_receive (Thread *thread, unsigned protected_data, Capability::Context *c)
void Thread_arch_receive_fail (Thread *thread)
unsigned *Thread_arch_info (Thread *thread, unsigned num)
void Memory_arch_init (Memory *mem)
void Memory_arch_free (Memory *mem)
bool Memory_arch_map (Memory *mem, Page *page, unsigned address, bool write)
void Memory_arch_unmap (Memory *mem, Page *page, unsigned address)
Page *Memory_arch_get_mapping (Memory *mem, unsigned address, bool *writable)
void Page_arch_update_mapping (Page *page)
void arch_register_interrupt (unsigned num, Receiver *r)

bool Memory::map (Page *page, unsigned address, bool write):
	return Memory_arch_map (this, page, address, write)
void Memory::unmap (Page *page, unsigned address):
	Memory_arch_unmap (this, page, address)
Page *Memory::get_mapping (unsigned address, bool *writable):
	return Memory_arch_get_mapping (this, address, writable)

#endif