/* * Copyright (c) 2012 Jakub Jermar * 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. */ /** @addtogroup kernel_generic_ipc * @{ */ /** @file */ #ifndef KERN_SYSIPC_OPS_H_ #define KERN_SYSIPC_OPS_H_ #include <ipc/ipc.h> #define SYSIPC_OP(op, call, ...) \ ({ \ sysipc_ops_t *ops = sysipc_ops_get((call)->request_method); \ assert(ops->op); \ ops->op((call), ##__VA_ARGS__); \ }) /** * This header declares the per-method IPC callbacks. Using these callbacks, * each IPC method (but system methods in particular), can define actions that * will be called at specific moments in the call life-cycle. * * Normally, the kernel will attempt to invoke the following callbacks in the * following order on each call: * * request_preprocess() * request_process() * answer_preprocess() * answer_process() * * This callback invocation sequence is a natural order of processing. Note, * however, that due to various special circumstances, callbacks may be called * also in a different than natural order of processing. This means that some * callbacks may be skipped and some others may be called instead. * * The additional callbacks that may be called are as follows: * * request_forget() * answer_cleanup() * * There are several notable scenarios in which some callbacks of the natural * order of processing will be skipped. * * The request_process(), answer_preprocess() and answer_process() callbacks * will be skipped if the call cannot be delivered to the callee. This may * happen when e.g. the request_preprocess() callback fails or the connection * to the callee is not functional. The next callback that will be invoked on * the call is request_forget(). * * The comments for each callback type describe the specifics of each callback * such as the context in which it is invoked and various constraints. */ typedef struct { /** * This callback is called from request_preprocess(). * * Context: caller * Caller alive: guaranteed * Races with: N/A * Invoked on: all calls */ errno_t (*request_preprocess)(call_t *, phone_t *); /** * This callback is called when the IPC cleanup code wins the race to * forget the call. * * Context: caller * Caller alive: guaranteed * Races with: request_process(), answer_cleanup(), * _ipc_answer_free_call() * Invoked on: all forgotten calls */ errno_t (*request_forget)(call_t *); /** * This callback is called from process_request(). * * Context: callee * Caller alive: no guarantee * Races with: request_forget() * Invoked on: all calls delivered to the callee */ int (*request_process)(call_t *, answerbox_t *); /** * This callback is called when answer_preprocess() loses the race to * answer the call. * * Context: callee * Caller alive: no guarantee * Races with: request_forget() * Invoked on: all forgotten calls */ errno_t (*answer_cleanup)(call_t *, ipc_data_t *); /** * This callback is called when answer_preprocess() wins the race to * answer the call. * * Context: callee * Caller alive: guaranteed * Races with: N/A * Invoked on: all answered calls */ errno_t (*answer_preprocess)(call_t *, ipc_data_t *); /** * This callback is called from process_answer(). * * Context: caller * Caller alive: guaranteed * Races with: N/A * Invoked on: all answered calls */ errno_t (*answer_process)(call_t *); } sysipc_ops_t; extern sysipc_ops_t *sysipc_ops_get(sysarg_t); extern errno_t null_request_preprocess(call_t *, phone_t *); extern errno_t null_request_forget(call_t *); extern int null_request_process(call_t *, answerbox_t *); extern errno_t null_answer_cleanup(call_t *, ipc_data_t *); extern errno_t null_answer_preprocess(call_t *, ipc_data_t *); extern errno_t null_answer_process(call_t *); #endif /** @} */