Rev 1088 | Rev 1141 | Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed
/*
* 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.
*/
#include <arch.h>
#include <proc/task.h>
#include <errno.h>
#include <mm/page.h>
#include <memstr.h>
#include <debug.h>
#include <ipc/ipc.h>
#include <ipc/sysipc.h>
#include <ipc/ipcrsc.h>
#include <print.h>
#include <arch.h>
#include <proc/thread.h>
#define GET_CHECK_PHONE(phone,phoneid,err) { \
if (phoneid > IPC_MAX_PHONES) { err; } \
phone = &TASK->phones[phoneid]; \
}
#define STRUCT_TO_USPACE(dst,src) copy_to_uspace(dst,src,sizeof(*(src)))
/** Return true if the method is a system method */
static inline int is_system_method(__native method)
{
if (method <= IPC_M_LAST_SYSTEM)
return 1;
return 0;
}
/** Return true if the message with this method is forwardable
*
* - some system messages may be forwarded, for some of them
* it is useless
*/
static inline int is_forwardable(__native method)
{
if (method == IPC_M_PHONE_HUNGUP)
return 0; /* This message is meant only for the receiver */
return 1;
}
/****************************************************/
/* Functions that preprocess answer before sending
* it to the recepient
*/
/** Return true if the caller (ipc_answer) should save
* the old call contents for answer_preprocess
*/
static inline int answer_need_old(call_t *call)
{
if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME)
return 1;
if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_ME_TO)
return 1;
return 0;
}
/** Interpret process answer as control information */
static inline void answer_preprocess(call_t *answer, ipc_data_t *olddata)
{
int phoneid;
if (IPC_GET_RETVAL(answer->data) == EHANGUP) {
/* Atomic operation */
answer->data.phone->callee = NULL;
}
if (!olddata)
return;
if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_TO_ME) {
phoneid = IPC_GET_ARG3(*olddata);
if (IPC_GET_RETVAL(answer->data)) {
/* The connection was not accepted */
phone_dealloc(phoneid);
} else {
/* The connection was accepted */
phone_connect(phoneid,&answer->sender->answerbox);
/* Set 'phone identification' as arg3 of response */
IPC_SET_ARG3(answer->data, (__native)&TASK->phones[phoneid]);
}
} else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME_TO) {
/* If the users accepted call, connect */
if (!IPC_GET_RETVAL(answer->data)) {
ipc_phone_connect((phone_t *)IPC_GET_ARG3(*olddata),
&TASK->answerbox);
}
}
}
/** Called before the request is sent
*
* @return 0 - no error, -1 - report error to user
*/
static int request_preprocess(call_t *call)
{
int newphid;
switch (IPC_GET_METHOD(call->data)) {
case IPC_M_CONNECT_ME_TO:
newphid = phone_alloc();
if (newphid < 0)
return ELIMIT;
/* Set arg3 for server */
IPC_SET_ARG3(call->data, (__native)&TASK->phones[newphid]);
call->flags |= IPC_CALL_CONN_ME_TO;
call->private = newphid;
break;
default:
break;
}
return 0;
}
/****************************************************/
/* Functions called to process received call/answer
* before passing to uspace
*/
/** Do basic kernel processing of received call answer */
static void process_answer(call_t *call)
{
if (IPC_GET_RETVAL(call->data) == EHANGUP && \
call->flags & IPC_CALL_FORWARDED)
IPC_SET_RETVAL(call->data, EFORWARD);
if (call->flags & IPC_CALL_CONN_ME_TO) {
if (IPC_GET_RETVAL(call->data))
phone_dealloc(call->private);
else
IPC_SET_ARG3(call->data, call->private);
}
}
/** Do basic kernel processing of received call request
*
* @return 0 - the call should be passed to userspace, 1 - ignore call
*/
static int process_request(answerbox_t *box,call_t *call)
{
int phoneid;
if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME) {
phoneid = phone_alloc();
if (phoneid < 0) { /* Failed to allocate phone */
IPC_SET_RETVAL(call->data, ELIMIT);
ipc_answer(box,call);
return -1;
}
IPC_SET_ARG3(call->data, phoneid);
}
return 0;
}
/** Send a call over IPC, wait for reply, return to user
*
* @return Call identification, returns -1 on fatal error,
-2 on 'Too many async request, handle answers first
*/
__native sys_ipc_call_sync_fast(__native phoneid, __native method,
__native arg1, ipc_data_t *data)
{
call_t call;
phone_t *phone;
int res;
GET_CHECK_PHONE(phone, phoneid, return ENOENT);
ipc_call_static_init(&call);
IPC_SET_METHOD(call.data, method);
IPC_SET_ARG1(call.data, arg1);
if (!(res=request_preprocess(&call))) {
ipc_call_sync(phone, &call);
process_answer(&call);
} else
IPC_SET_RETVAL(call.data, res);
STRUCT_TO_USPACE(&data->args, &call.data.args);
return 0;
}
/** Synchronous IPC call allowing to send whole message */
__native sys_ipc_call_sync(__native phoneid, ipc_data_t *question,
ipc_data_t *reply)
{
call_t call;
phone_t *phone;
int res;
ipc_call_static_init(&call);
copy_from_uspace(&call.data.args, &question->args, sizeof(call.data.args));
GET_CHECK_PHONE(phone, phoneid, return ENOENT);
if (!(res=request_preprocess(&call))) {
ipc_call_sync(phone, &call);
process_answer(&call);
} else
IPC_SET_RETVAL(call.data, res);
STRUCT_TO_USPACE(&reply->args, &call.data.args);
return 0;
}
/** Check that the task did not exceed allowed limit
*
* @return 0 - Limit OK, -1 - limit exceeded
*/
static int check_call_limit(void)
{
if (atomic_preinc(&TASK->active_calls) > IPC_MAX_ASYNC_CALLS) {
atomic_dec(&TASK->active_calls);
return -1;
}
return 0;
}
/** Send an asynchronous call over ipc
*
* @return Call identification, returns -1 on fatal error,
-2 on 'Too many async request, handle answers first
*/
__native sys_ipc_call_async_fast(__native phoneid, __native method,
__native arg1, __native arg2)
{
call_t *call;
phone_t *phone;
int res;
if (check_call_limit())
return IPC_CALLRET_TEMPORARY;
GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
call = ipc_call_alloc();
IPC_SET_METHOD(call->data, method);
IPC_SET_ARG1(call->data, arg1);
IPC_SET_ARG2(call->data, arg2);
if (!(res=request_preprocess(call)))
ipc_call(phone, call);
else
ipc_backsend_err(phone, call, res);
return (__native) call;
}
/** Synchronous IPC call allowing to send whole message
*
* @return The same as sys_ipc_call_async
*/
__native sys_ipc_call_async(__native phoneid, ipc_data_t *data)
{
call_t *call;
phone_t *phone;
int res;
if (check_call_limit())
return IPC_CALLRET_TEMPORARY;
GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
call = ipc_call_alloc();
copy_from_uspace(&call->data.args, &data->args, sizeof(call->data.args));
if (!(res=request_preprocess(call)))
ipc_call(phone, call);
else
ipc_backsend_err(phone, call, res);
return (__native) call;
}
/** Forward received call to another destination
*
* The arg1 and arg2 are changed in the forwarded message
*
* Warning: If implementing non-fast version, make sure that
* arg3 is not rewritten for certain system IPC
*/
__native sys_ipc_forward_fast(__native callid, __native phoneid,
__native method, __native arg1)
{
call_t *call;
phone_t *phone;
call = get_call(callid);
if (!call)
return ENOENT;
call->flags |= IPC_CALL_FORWARDED;
GET_CHECK_PHONE(phone, phoneid, {
IPC_SET_RETVAL(call->data, EFORWARD);
ipc_answer(&TASK->answerbox, call);
return ENOENT;
});
if (!is_forwardable(IPC_GET_METHOD(call->data))) {
IPC_SET_RETVAL(call->data, EFORWARD);
ipc_answer(&TASK->answerbox, call);
return EPERM;
}
/* Userspace is not allowed to change method of system methods
* on forward, allow changing ARG1 and ARG2 by means of method and arg1
*/
if (is_system_method(IPC_GET_METHOD(call->data))) {
if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME)
phone_dealloc(IPC_GET_ARG3(call->data));
IPC_SET_ARG1(call->data, method);
IPC_SET_ARG2(call->data, arg1);
} else {
IPC_SET_METHOD(call->data, method);
IPC_SET_ARG1(call->data, arg1);
}
return ipc_forward(call, phone, &TASK->answerbox);
}
/** Send IPC answer */
__native sys_ipc_answer_fast(__native callid, __native retval,
__native arg1, __native arg2)
{
call_t *call;
ipc_data_t saved_data;
int saveddata = 0;
call = get_call(callid);
if (!call)
return ENOENT;
if (answer_need_old(call)) {
memcpy(&saved_data, &call->data, sizeof(call->data));
saveddata = 1;
}
IPC_SET_RETVAL(call->data, retval);
IPC_SET_ARG1(call->data, arg1);
IPC_SET_ARG2(call->data, arg2);
answer_preprocess(call, saveddata ? &saved_data : NULL);
ipc_answer(&TASK->answerbox, call);
return 0;
}
/** Send IPC answer */
__native sys_ipc_answer(__native callid, ipc_data_t *data)
{
call_t *call;
ipc_data_t saved_data;
int saveddata = 0;
call = get_call(callid);
if (!call)
return ENOENT;
if (answer_need_old(call)) {
memcpy(&saved_data, &call->data, sizeof(call->data));
saveddata = 1;
}
copy_from_uspace(&call->data.args, &data->args,
sizeof(call->data.args));
answer_preprocess(call, saveddata ? &saved_data : NULL);
ipc_answer(&TASK->answerbox, call);
return 0;
}
/** Hang up the phone
*
*/
__native sys_ipc_hangup(int phoneid)
{
phone_t *phone;
GET_CHECK_PHONE(phone, phoneid, return ENOENT);
if (ipc_phone_hangup(phone))
return -1;
return 0;
}
/** Wait for incoming ipc call or answer
*
* @param calldata Pointer to buffer where the call/answer data is stored
* @param taskid On 'CONNECT_ME_TO' call it is filled with 'taskid' of
* the caller.
* @param flags
* @return Callid, if callid & 1, then the call is answer
*/
__native sys_ipc_wait_for_call(ipc_data_t *calldata, __native flags)
{
call_t *call;
restart:
call = ipc_wait_for_call(&TASK->answerbox, flags);
if (!call)
return 0;
if (call->flags & IPC_CALL_ANSWERED) {
process_answer(call);
ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
atomic_dec(&TASK->active_calls);
if (call->flags & IPC_CALL_DISCARD_ANSWER) {
ipc_call_free(call);
goto restart;
}
STRUCT_TO_USPACE(&calldata->args, &call->data.args);
ipc_call_free(call);
return ((__native)call) | IPC_CALLID_ANSWERED;
}
if (process_request(&TASK->answerbox, call))
goto restart;
/* Include phone address('id') of the caller in the request,
* copy whole call->data, not only call->data.args */
STRUCT_TO_USPACE(calldata, &call->data);
return (__native)call;
}