/*
* Copyright (C) 2006 Ondrej Palkovsky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __IPC_H__
#define __IPC_H__
/* Length of data being transfered with IPC call */
/* - the uspace may not be able to utilize full length */
#define IPC_CALL_LEN 4
/** Maximum active async calls per thread */
#define IPC_MAX_ASYNC_CALLS 4
/* Flags for calls */
#define IPC_CALL_ANSWERED (1<<0) /**< This is answer to a call */
#define IPC_CALL_STATIC_ALLOC (1<<1) /**< This call will not be freed on error */
#define IPC_CALL_DISCARD_ANSWER (1<<2) /**< Answer will not be passed to
* userspace, will be discarded */
#define IPC_CALL_FORWARDED (1<<3) /* Call was forwarded */
#define IPC_CALL_CONN_ME_TO (1<<4) /* Identify connect_me_to */
/* Flags for ipc_wait_for_call */
#define IPC_WAIT_NONBLOCKING 1
/* Flags of callid (the addresses are aligned at least to 4,
* that is why we can use bottom 2 bits of the call address
*/
#define IPC_CALLID_ANSWERED 1 /**< Type of this msg is 'answer' */
#define IPC_CALLID_NOTIFICATION 2 /**< Type of this msg is 'notification' */
/* Return values from IPC_ASYNC */
#define IPC_CALLRET_FATAL -1
#define IPC_CALLRET_TEMPORARY -2
/* Macros for manipulating calling data */
#define IPC_SET_RETVAL(data, retval) ((data).args[0] = (retval))
#define IPC_SET_METHOD(data, val) ((data).args[0] = (val))
#define IPC_SET_ARG1(data, val) ((data).args[1] = (val))
#define IPC_SET_ARG2(data, val) ((data).args[2] = (val))
#define IPC_SET_ARG3(data, val) ((data).args[3] = (val))
#define IPC_GET_METHOD(data) ((data).args[0])
#define IPC_GET_RETVAL(data) ((data).args[0])
#define IPC_GET_ARG1(data) ((data).args[1])
#define IPC_GET_ARG2(data) ((data).args[2])
#define IPC_GET_ARG3(data) ((data).args[3])
/* Well known phone descriptors */
#define PHONE_NS 0
/* System-specific methods - only through special syscalls
* These methods have special behaviour
*/
/** Protocol for CONNECT - TO - ME
*
* Calling process asks the callee to create a callback connection,
* so that it can start initiating new messages.
*
* The protocol for negotiating is:
* - sys_connect_to_me - sends a message IPC_M_CONNECTTOME
* - sys_wait_for_call - upon receipt tries to allocate new phone
* - if it fails, responds with ELIMIT
* - passes call to userspace. If userspace
* responds with error, phone is deallocated and
* error is sent back to caller. Otherwise
* the call is accepted and the response is sent back.
* - the allocated phoneid is passed to userspace
* (on the receiving sid) as ARG3 of the call.
* - the caller obtains taskid of the called thread
*/
#define IPC_M_CONNECT_TO_ME 1
/** Protocol for CONNECT - ME - TO
*
* Calling process asks the callee to create for him a new connection.
* E.g. the caller wants a name server to connect him to print server.
*
* The protocol for negotiating is:
* - sys_connect_me_to - send a synchronous message to name server
* indicating that it wants to be connected to some
* service
* - arg1/2 are user specified, arg3 contains
* address of the phone that should be connected
* (TODO: it leaks to userspace)
* recepient - if ipc_answer == 0, then accept connection
* - otherwise connection refused
* - recepient may forward message. Forwarding
* system message
*
*/
#define IPC_M_CONNECT_ME_TO 2
/** This message is sent to answerbox when the phone
* is hung up
*/
#define IPC_M_PHONE_HUNGUP 3
/* Well-known methods */
#define IPC_M_LAST_SYSTEM 511
#define IPC_M_PING 512
/* User methods */
#define FIRST_USER_METHOD 1024
#ifdef KERNEL
#include <synch/mutex.h>
#include <synch/condvar.h>
#include <adt/list.h>
#define IPC_MAX_PHONES 16
typedef struct answerbox_s answerbox_t;
typedef struct phone_s phone_t;
typedef struct {
__native args[IPC_CALL_LEN];
phone_t *phone;
}ipc_data_t;
struct answerbox_s {
SPINLOCK_DECLARE(lock);
task_t *task;
waitq_t wq;
link_t connected_phones; /**< Phones connected to this answerbox */
link_t calls; /**< Received calls */
link_t dispatched_calls; /* Should be hash table in the future */
link_t answers; /**< Answered calls */
};
typedef enum {
IPC_BUSY_FREE = 0,
IPC_BUSY_CONNECTING,
IPC_BUSY_CONNECTED
} ipc_busy_t;
struct phone_s {
SPINLOCK_DECLARE(lock);
link_t list;
answerbox_t *callee;
ipc_busy_t busy;
atomic_t active_calls;
};
typedef struct {
link_t list;
int flags;
/* Identification of the caller */
task_t *sender;
/* The caller box is different from sender->answerbox
* for synchronous calls
*/
answerbox_t *callerbox;
__native private; /**< Private data to internal IPC */
ipc_data_t data; /**< Data passed from/to userspace */
}call_t;
extern void ipc_init(void);
extern call_t * ipc_wait_for_call(answerbox_t *box, int flags);
extern void ipc_answer(answerbox_t *box, call_t *request);
extern int ipc_call(phone_t *phone, call_t *call);
extern void ipc_call_sync(phone_t *phone, call_t *request);
extern void ipc_phone_init(phone_t *phone);
extern void ipc_phone_connect(phone_t *phone, answerbox_t *box);
extern void ipc_call_free(call_t *call);
extern call_t * ipc_call_alloc(void);
extern void ipc_answerbox_init(answerbox_t *box);
extern void ipc_call_static_init(call_t *call);
extern void task_print_list(void);
extern int ipc_forward(call_t *call, phone_t *newphone, answerbox_t *oldbox);
extern void ipc_cleanup(task_t *task);
extern int ipc_phone_hangup(phone_t *phone);
extern void ipc_backsend_err(phone_t *phone, call_t *call, __native err);
extern answerbox_t *ipc_phone_0;
#endif
#endif