source: mainline/kernel/generic/include/proc/task.h@ 1004b37

/*
 * Copyright (c) 2001-2004 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 genericproc
 * @{
 */
/** @file
 */

#ifndef KERN_TASK_H_
#define KERN_TASK_H_

#include <cpu.h>
#include <synch/spinlock.h>
#include <synch/mutex.h>
#include <synch/rwlock.h>
#include <synch/futex.h>
#include <adt/btree.h>
#include <adt/list.h>
#include <security/cap.h>
#include <arch/proc/task.h>
#include <arch/proc/thread.h>
#include <arch/context.h>
#include <arch/fpu_context.h>
#include <arch/cpu.h>
#include <mm/tlb.h>
#include <proc/scheduler.h>

#define IPC_MAX_PHONES  16

struct answerbox;
struct task;
struct thread;

typedef enum {
        IPC_PHONE_FREE = 0,     /**< Phone is free and can be allocated */
        IPC_PHONE_CONNECTING,   /**< Phone is connecting somewhere */
        IPC_PHONE_CONNECTED,    /**< Phone is connected */
        IPC_PHONE_HUNGUP,       /**< Phone is hung up, waiting for answers to come */
        IPC_PHONE_SLAMMED       /**< Phone was hungup from server */
} ipc_phone_state_t;

/** Structure identifying phone (in TASK structure) */
typedef struct {
        SPINLOCK_DECLARE(lock);
        link_t link;
        struct answerbox *callee;
        ipc_phone_state_t state;
        atomic_t active_calls;
} phone_t;

typedef struct answerbox {
        SPINLOCK_DECLARE(lock);

        struct task *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 */

        SPINLOCK_DECLARE(irq_lock);
        link_t irq_notifs;              /**< Notifications from IRQ handlers */
        link_t irq_head;                /**< IRQs with notifications to this answerbox. */
} answerbox_t;

/** Task structure. */
typedef struct task {
        /** Task lock.
         *
         * Must be acquired before threads_lock and thread lock of any of its threads.
         */
        SPINLOCK_DECLARE(lock);
        
        char *name;
        struct thread *main_thread;     /**< Pointer to the main thread. */
        link_t th_head;         /**< List of threads contained in this task. */
        as_t *as;               /**< Address space. */
        task_id_t taskid;       /**< Unique identity of task */
        context_id_t context;   /**< Task security context */

        /** If this is true, new threads can become part of the task. */
        bool accept_new_threads;

        count_t refcount;       /**< Number of references (i.e. threads). */

        cap_t capabilities;     /**< Task capabilities. */

        /* IPC stuff */
        answerbox_t answerbox;  /**< Communication endpoint */
        phone_t phones[IPC_MAX_PHONES];
        atomic_t active_calls;  /**< Active asynchronous messages.
                                 *   It is used for limiting uspace to
                                 *   certain extent. */
        
        task_arch_t arch;       /**< Architecture specific task data. */
        
        /**
         * Serializes access to the B+tree of task's futexes. This mutex is
         * independent on the task spinlock.
         */
        mutex_t futexes_lock;
        btree_t futexes;        /**< B+tree of futexes referenced by this task. */
        
        uint64_t cycles;        /**< Accumulated accounting. */
} task_t;

typedef void (* timeout_handler_t)(void *arg);

typedef struct {
        SPINLOCK_DECLARE(lock);

        link_t link;                    /**< Link to the list of active timeouts on THE->cpu */
        
        uint64_t ticks;                 /**< Timeout will be activated in this amount of clock() ticks. */

        timeout_handler_t handler;      /**< Function that will be called on timeout activation. */
        void *arg;                      /**< Argument to be passed to handler() function. */
        
        cpu_t *cpu;                     /**< On which processor is this timeout registered. */
} timeout_t;

/** Thread states. */
typedef enum {
        Invalid,        /**< It is an error, if thread is found in this state. */
        Running,        /**< State of a thread that is currently executing on some CPU. */
        Sleeping,       /**< Thread in this state is waiting for an event. */
        Ready,          /**< State of threads in a run queue. */
        Entering,       /**< Threads are in this state before they are first readied. */
        Exiting,        /**< After a thread calls thread_exit(), it is put into Exiting state. */
        Undead          /**< Threads that were not detached but exited are in the Undead state. */
} state_t;

/** Join types. */
typedef enum {
        None,
        TaskClnp,       /**< The thread will be joined by ktaskclnp thread. */
        TaskGC          /**< The thread will be joined by ktaskgc thread. */
} thread_join_type_t;

SPINLOCK_EXTERN(tasks_lock);
extern btree_t tasks_btree;

extern void task_init(void);
extern task_t *task_create(as_t *as, char *name);
extern void task_destroy(task_t *t);
extern task_t *task_run_program(void *program_addr, char *name);
extern task_t *task_find_by_id(task_id_t id);
extern int task_kill(task_id_t id);
extern uint64_t task_get_accounting(task_t *t);

extern void cap_set(task_t *t, cap_t caps);
extern cap_t cap_get(task_t *t);


#ifndef task_create_arch
extern void task_create_arch(task_t *t);
#endif

#ifndef task_destroy_arch
extern void task_destroy_arch(task_t *t);
#endif

extern unative_t sys_task_get_id(task_id_t *uspace_task_id);

#endif

/** @}
 */