#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

// 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

struct Page
struct Thread
struct Message
struct Receiver
struct Capability
struct Caps
struct Memory

typedef Page *PageP
typedef Thread *ThreadP
typedef Message *MessageP
typedef Receiver *ReceiverP
typedef Capability *CapabilityP
typedef Caps *CapsP
typedef Memory *MemoryP
typedef void *Pointer

typedef unsigned Protected

struct CapRef:
	CapsP caps
	unsigned index
	inline Capability *deref ()
	operator bool ():
		return deref () != NULL
	Capability *operator-> ():
		return deref ()
	void reset ():
		caps = NULL
	CapRef (CapsP c, unsigned i) : caps (c), index (i):
	CapRef () : caps (NULL), index (~0):
	inline void clone (CapRef source, bool copy)
	inline void set (Receiver *target, Protected pdata, CapRef parent, CapRef *parent_ptr = NULL)

struct Object:
	CapRef refs
	MemoryP address_space
	// Next and previous object of the same type in any page.
	Pointer prev, next
	inline bool is_free ()

struct Free : public Object:
	// 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::is_free ():
	return ((Free *)this)->marker == ~0

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

struct Message : public Object:
	Protected protected_data
	unsigned data[4]
	unsigned char capabilities[4]

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

struct Thread : public Object:
	ReceiverP receivers
	unsigned pc, sp
	Thread_arch arch
	unsigned flags
	ThreadP schedule_prev, schedule_next
	CapRef rcaps[4]
	// caps is an array of slots pointers to Capses.
	unsigned slots
	// TODO: handle freeing of capses which are in use.
	CapsP caps[1]
	void raise (unsigned code, unsigned data)
	void run ()
	void unrun ()
	void wait (CapRef c0, CapRef c1, CapRef c2, CapRef c3)
	void unwait ()
	bool is_waiting ():
		return flags & THREAD_FLAG_WAITING
	CapRef find_capability (unsigned code, bool *copy)

struct Receiver : public Object:
	ThreadP owner
	ReceiverP prev_owned, next_owned
	ReceiverP prev_alarm, next_alarm
	unsigned alarm_count
	// random is used like the tlb random register to find invalid caps to store the message to.
	unsigned random
	CapsP caps
	// These are capabilities which call this receiver on invoke.
	CapRef capabilities
	// The message queue.  Messages are added at the tail, and removed at the front.
	MessageP messages
	MessageP last_message
	Protected reply_protected_data
	bool protected_only
	void own (ThreadP o)
	void orphan ()
	bool try_deliver ()
	bool send_message (Protected protected_data, Capability::Context *c)

struct Page : public Object:
	unsigned frame
	unsigned flags
	PageP share_first
	PageP share_prev, share_next
	Page_arch arch
	void forget ()

struct Caps : public Object:
	unsigned size
	Capability caps[1]
	Capability *cap (unsigned idx):
		return &caps[idx]
	void set (unsigned index, Receiver *target, Protected pdata, CapRef parent, CapRef *parent_ptr = NULL)
	void clone (unsigned index, CapRef source, bool copy)

struct Memory : public Object:
	Free *frees
	PageP pages
	ThreadP threads
	ReceiverP receivers
	CapsP capses
	MemoryP 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 (unsigned num = 1)
	void unuse (unsigned num = 1)
	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 (unsigned size)
	Message *alloc_message (Receiver *target)
	Receiver *alloc_receiver ()
	Caps *alloc_caps (unsigned size)
	Memory *alloc_memory ()

	void free_page (Page *page)
	void free_thread (Thread *thread)
	void free_message (Receiver *owner, Message *message)
	void free_receiver (Receiver *receiver)
	void free_caps (Caps *page)
	void free_memory (Memory *mem)

	void free_obj (Object *obj, void **first)

// 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_impl (unsigned n, unsigned line, char const *name, char const *message = "")
	EXTERN unsigned dbg_code
	EXTERN CapRef dbg_cap
	void dbg_log_char (unsigned ch)
	void dbg_log (char const *str)
	void dbg_log_num (unsigned num)

#define panic(n, m) panic_impl ((n), __LINE__, __PRETTY_FUNCTION__, (m))

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

EXTERN Memory top_memory
EXTERN ReceiverP first_alarm
EXTERN Thread idle
EXTERN Memory idle_memory
EXTERN Page idle_page
EXTERN ThreadP first_scheduled
EXTERN ThreadP current, old_current
EXTERN bool do_schedule

// Defined in memory.cc
unsigned init_memory (unsigned mem)
unsigned raw_zalloc ()
void raw_pfree (unsigned page)
unsigned phys_alloc (unsigned num)
void phys_free (unsigned page, unsigned num)

// Defined by architecture-specific files.
void Thread_arch_init (Thread *thread)
void Thread_arch_receive (Thread *thread, Protected protected_data, unsigned *data)
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, ReceiverP 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)
Capability *CapRef::deref ():
	return caps ? caps->cap (index) : NULL
void CapRef::clone (CapRef source, bool copy):
	caps->clone (index, source, copy)
void CapRef::set (Receiver *target, Protected pdata, CapRef parent, CapRef *parent_ptr):
	caps->set (index, target, pdata, parent, parent_ptr)

#define assert(x) do { if (!(x)) panic (__LINE__, "assertion failed"); } while (0)

#endif