| 0,0 → 1,218 |
|---|
| /* |
| * 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. |
| */ |
| |
| /* Lock ordering |
| * |
| * First the answerbox, then the phone |
| */ |
| |
| #include <synch/waitq.h> |
| #include <ipc/ipc.h> |
| #include <errno.h> |
| #include <mm/slab.h> |
| #include <arch.h> |
| #include <proc/task.h> |
| #include <memstr.h> |
| #include <debug.h> |
| |
| #include <print.h> |
| #include <proc/thread.h> |
| |
| answerbox_t *ipc_central_box; |
| |
| static slab_cache_t *ipc_call_slab; |
| |
| /** Allocate & initialize call structure |
| * |
| * The call is initialized, so that the reply will be directed |
| * to TASK->answerbox |
| */ |
| call_t * ipc_call_alloc(void) |
| { |
| call_t *call; |
| |
| call = slab_alloc(ipc_call_slab, 0); |
| memsetb((__address)call, sizeof(*call), 0); |
| call->callerbox = &TASK->answerbox; |
| |
| return call; |
| } |
| |
| /** Deallocate call stracuture */ |
| void ipc_call_free(call_t *call) |
| { |
| slab_free(ipc_call_slab, call); |
| } |
| |
| /** Initialize answerbox structure |
| */ |
| void ipc_answerbox_init(answerbox_t *box) |
| { |
| spinlock_initialize(&box->lock, "abox_lock"); |
| waitq_initialize(&box->wq); |
| list_initialize(&box->connected_phones); |
| list_initialize(&box->calls); |
| list_initialize(&box->dispatched_calls); |
| list_initialize(&box->answers); |
| } |
| |
| /** Initialize phone structure and connect phone to naswerbox |
| */ |
| void ipc_phone_init(phone_t *phone, answerbox_t *box) |
| { |
| spinlock_initialize(&phone->lock, "phone_lock"); |
| |
| phone->callee = box; |
| spinlock_lock(&box->lock); |
| list_append(&phone->list, &box->connected_phones); |
| spinlock_unlock(&box->lock); |
| } |
| |
| /** Disconnect phone from answerbox */ |
| void ipc_phone_destroy(phone_t *phone) |
| { |
| answerbox_t *box = phone->callee; |
| |
| ASSERT(box); |
| |
| spinlock_lock(&box->lock); |
| list_remove(&phone->list); |
| spinlock_unlock(&box->lock); |
| } |
| |
| |
| /** Send a request using phone to answerbox |
| * |
| * @param phone Phone connected to answerbox |
| * @param request Request to be sent |
| */ |
| void ipc_call(phone_t *phone, call_t *request) |
| { |
| answerbox_t *box = phone->callee; |
| |
| ASSERT(box); |
| |
| spinlock_lock(&box->lock); |
| list_append(&request->list, &box->calls); |
| spinlock_unlock(&box->lock); |
| waitq_wakeup(&box->wq, 0); |
| } |
| |
| /** Answer message back to phone |
| * |
| * @param box Answerbox that is answering the message |
| * @param request Modified request that is being sent back |
| */ |
| void ipc_answer(answerbox_t *box, call_t *request) |
| { |
| answerbox_t *callerbox = request->callerbox; |
| |
| request->flags |= IPC_CALL_ANSWERED; |
| |
| spinlock_lock(&box->lock); |
| spinlock_lock(&callerbox->lock); |
| |
| list_remove(&request->list); |
| list_append(&request->list, &callerbox->answers); |
| waitq_wakeup(&callerbox->wq, 0); |
| |
| spinlock_unlock(&callerbox->lock); |
| spinlock_unlock(&box->lock); |
| } |
| |
| /** Wait for phone call |
| * |
| * @return Recived message address |
| * - to distinguish between call and answer, look at call->flags |
| */ |
| call_t * ipc_wait_for_call(answerbox_t *box, int flags) |
| { |
| call_t *request; |
| |
| if ((flags & IPC_WAIT_NONBLOCKING)) { |
| if (waitq_sleep_timeout(&box->wq,SYNCH_NO_TIMEOUT,SYNCH_NON_BLOCKING) == ESYNCH_WOULD_BLOCK) |
| return 0; |
| } else { |
| waitq_sleep(&box->wq); |
| } |
| |
| |
| // TODO - might need condition variable+mutex if we want to support |
| // removing of requests from queue before dispatch |
| spinlock_lock(&box->lock); |
| /* Handle answers first */ |
| if (!list_empty(&box->answers)) { |
| request = list_get_instance(box->answers.next, call_t, list); |
| list_remove(&request->list); |
| } else { |
| ASSERT (! list_empty(&box->calls)); |
| request = list_get_instance(box->calls.next, call_t, list); |
| list_remove(&request->list); |
| /* Append request to dispatch queue */ |
| list_append(&request->list, &box->dispatched_calls); |
| } |
| spinlock_unlock(&box->lock); |
| |
| return request; |
| } |
| |
| /** Initilize ipc subsystem */ |
| void ipc_init(void) |
| { |
| ipc_call_slab = slab_cache_create("ipc_call", |
| sizeof(call_t), |
| 0, |
| NULL, NULL, 0); |
| } |
| |
| static void ipc_phonecompany_thread(void *data) |
| { |
| call_t *call; |
| |
| printf("Phone company started.\n"); |
| while (1) { |
| call = ipc_wait_for_call(&TASK->answerbox, 0); |
| printf("Received phone call - %P %P\n", |
| call->data[0], call->data[1]); |
| ipc_answer(&TASK->answerbox, call); |
| printf("Call answered.\n"); |
| } |
| } |
| |
| void ipc_create_phonecompany(void) |
| { |
| thread_t *t; |
| |
| if ((t = thread_create(ipc_phonecompany_thread, "phonecompany", |
| TASK, 0))) |
| thread_ready(t); |
| else |
| panic("thread_create/phonecompany"); |
| |
| ipc_central_box = &TASK->answerbox; |
| } |