WebSVN – HelenOS – Diff – /branches/tracing/kernel/generic/src/udebug/udebug_ops.c


/*
 * Copyright (c) 2008 Jiri Svoboda
 * 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 generic
 * @{
 */
 
/**
 * @file
 * @brief   Udebug operations.
 *
 * Udebug operations on tasks and threads are implemented here. The
 * functions defined here are called from the udebug_ipc module
 * when servicing udebug IPC messages.
 */
 
#include <debug.h>
#include <proc/task.h>
#include <proc/thread.h>
#include <arch.h>
#include <errno.h>
#include <print.h>
#include <syscall/copy.h>
#include <ipc/ipc.h>
#include <udebug/udebug.h>
#include <udebug/udebug_ops.h>
 
/**
 * Prepare a thread for a debugging operation.
 *
 * Simply put, return thread t with t->udebug.lock held,
 * but only if it verifies all conditions.
 *
 * Specifically, verifies that thread t exists, is a userspace thread,
 * and belongs to the current task (TASK). Verifies, that the thread
 * is (or is not) go according to being_go (typically false).
 * It also locks t->udebug.lock, making sure that t->udebug.active
 * is true - that the thread is in a valid debugging session.
 *
 * With this verified and the t->udebug.lock mutex held, it is ensured
 * that the thread cannot leave the debugging session, let alone cease
 * to exist.
 *
 * In this function, holding the TASK->udebug.lock mutex prevents the
 * thread from leaving the debugging session, while relaxing from
 * the t->lock spinlock to the t->udebug.lock mutex.
 *
 * @param t     Pointer, need not at all be valid.
 * @param being_go  Required thread state.
 *
 * Returns EOK if all went well, or an error code otherwise.
 */
static int _thread_op_begin(thread_t *t, bool being_go)
{
    task_id_t taskid;
    ipl_t ipl;
 
    taskid = TASK->taskid;
 
    mutex_lock(&TASK->udebug.lock);
 
    /* thread_exists() must be called with threads_lock held */
    ipl = interrupts_disable();
    spinlock_lock(&threads_lock);
 
    if (!thread_exists(t)) {
        spinlock_unlock(&threads_lock);
        interrupts_restore(ipl);
        mutex_unlock(&TASK->udebug.lock);
        return ENOENT;
    }
 
    /* t->lock is enough to ensure the thread's existence */
    spinlock_lock(&t->lock);
    spinlock_unlock(&threads_lock);
 
    /* Verify that 't' is a userspace thread. */
    if ((t->flags & THREAD_FLAG_USPACE) == 0) {
        /* It's not, deny its existence */
        spinlock_unlock(&t->lock);
        interrupts_restore(ipl);
        mutex_unlock(&TASK->udebug.lock);
        return ENOENT;
    }
 
    /* Verify debugging state. */
    if (t->udebug.active != true) {
        /* Not in debugging session or undesired GO state */
        spinlock_unlock(&t->lock);
        interrupts_restore(ipl);
        mutex_unlock(&TASK->udebug.lock);
        return ENOENT;
    }
 
    /*
     * Since the thread has active == true, TASK->udebug.lock
     * is enough to ensure its existence and that active remains
     * true.
     */
    spinlock_unlock(&t->lock);
    interrupts_restore(ipl);
 
    /* Only mutex TASK->udebug.lock left. */
   
    /* Now verify that the thread belongs to the current task. */
    if (t->task != TASK) {
        /* No such thread belonging this task*/
        mutex_unlock(&TASK->udebug.lock);
        return ENOENT;
    }
 
    /*
     * Now we need to grab the thread's debug lock for synchronization
     * of the threads stoppability/stop state.
     */
    mutex_lock(&t->udebug.lock);
 
    /* The big task mutex is no longer needed. */
    mutex_unlock(&TASK->udebug.lock);
 
    if (t->udebug.go != being_go) {
        /* Not in debugging session or undesired GO state. */
        mutex_unlock(&t->udebug.lock);
        return EINVAL;
    }
 
    /* Only t->udebug.lock left. */
 
    return EOK; /* All went well. */
}
 
/** End debugging operation on a thread. */
static void _thread_op_end(thread_t *t)
{
    mutex_unlock(&t->udebug.lock);
}
 
/** Begin debugging the current task.
 *
 * Initiates a debugging session for the current task (and its threads).
 * When the debugging session has started a reply will be sent to the
 * UDEBUG_BEGIN call. This may happen immediately in this function if
 * all the threads in this task are stoppable at the moment and in this
 * case the function returns 1.
 *
 * Otherwise the function returns 0 and the reply will be sent as soon as
 * all the threads become stoppable (i.e. they can be considered stopped).
 *
 * @param call  The BEGIN call we are servicing.
 * @return  0 (OK, but not done yet), 1 (done) or negative error code.
 */
int udebug_begin(call_t *call)
{
    int reply;
 
    thread_t *t;
    link_t *cur;
 
    LOG("Debugging task %llu", TASK->taskid);
 
    mutex_lock(&TASK->udebug.lock);
 
 
    if (TASK->udebug.dt_state != UDEBUG_TS_INACTIVE) {
        mutex_unlock(&TASK->udebug.lock);
 
 
        return EBUSY;
    }
 
    TASK->udebug.dt_state = UDEBUG_TS_BEGINNING;
    TASK->udebug.begin_call = call;
    TASK->udebug.debugger = call->sender;
 
    if (TASK->udebug.not_stoppable_count == 0) {
        TASK->udebug.dt_state = UDEBUG_TS_ACTIVE;
        TASK->udebug.begin_call = NULL;
        reply = 1; /* immediate reply */
    } else {
        reply = 0; /* no reply */
    }
   
    /* Set udebug.active on all of the task's userspace threads. */
 
    for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) {
        t = list_get_instance(cur, thread_t, th_link);
 
        mutex_lock(&t->udebug.lock);
        if ((t->flags & THREAD_FLAG_USPACE) != 0)
            t->udebug.active = true;
        mutex_unlock(&t->udebug.lock);
    }
 
    mutex_unlock(&TASK->udebug.lock);
 
 
 
 
    return reply;
}
 
/** Finish debugging the current task.
 *
 * Closes the debugging session for the current task.
 * @return Zero on success or negative error code.
 */
int udebug_end(void)
{
    int rc;
 
    LOG("Task %" PRIu64, TASK->taskid);
 
    mutex_lock(&TASK->udebug.lock);
 
 
    rc = udebug_task_cleanup(TASK);
 
    mutex_unlock(&TASK->udebug.lock);
 
    return rc;
}
 
/** Set the event mask.
 *
 * Sets the event mask that determines which events are enabled.
 *
 * @param mask  Or combination of events that should be enabled.
 * @return  Zero on success or negative error code.
 */
int udebug_set_evmask(udebug_evmask_t mask)
{
    LOG("mask = 0x%x", mask);
 
    mutex_lock(&TASK->udebug.lock);
 
    if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {
        mutex_unlock(&TASK->udebug.lock);
 
 
        return EINVAL;
    }
 
    TASK->udebug.evmask = mask;
 
    mutex_unlock(&TASK->udebug.lock);
 
    return 0;
}
 
/** Give thread GO.
 *
 * Upon recieving a go message, the thread is given GO. Being GO
 * means the thread is allowed to execute userspace code (until
 * a debugging event or STOP occurs, at which point the thread loses GO.
 *
 * @param t The thread to operate on (unlocked and need not be valid).
 * @param call  The GO call that we are servicing.
 */
int udebug_go(thread_t *t, call_t *call)
{
    int rc;
 
    /* On success, this will lock t->udebug.lock. */
    rc = _thread_op_begin(t, false);
    if (rc != EOK) {
        return rc;
    }
 
    t->udebug.go_call = call;
    t->udebug.go = true;
    t->udebug.cur_event = 0;    /* none */
 
    /*
     * Neither t's lock nor threads_lock may be held during wakeup.
     */
    waitq_wakeup(&t->udebug.go_wq, WAKEUP_FIRST);
 
    _thread_op_end(t);
 
    return 0;
}
 
/** Stop a thread (i.e. take its GO away)
 *
 * Generates a STOP event as soon as the thread becomes stoppable (i.e.
 * can be considered stopped).
 *
 * @param t The thread to operate on (unlocked and need not be valid).
 * @param call  The GO call that we are servicing.
 */
int udebug_stop(thread_t *t, call_t *call)
{
    int rc;
 
    LOG("udebug_stop()");
 
    /*
     * On success, this will lock t->udebug.lock. Note that this makes sure
     * the thread is not stopped.
     */
    rc = _thread_op_begin(t, true);
    if (rc != EOK) {
        return rc;
    }
 
    /* Take GO away from the thread. */
    t->udebug.go = false;
 
    if (t->udebug.stoppable != true) {
        /* Answer will be sent when the thread becomes stoppable. */
        _thread_op_end(t);
        return 0;
    }
 
    /*
     * Answer GO call.
     */
 
 
    /* Make sure nobody takes this call away from us. */
    call = t->udebug.go_call;
    t->udebug.go_call = NULL;
 
    IPC_SET_RETVAL(call->data, 0);
    IPC_SET_ARG1(call->data, UDEBUG_EVENT_STOP);
 
 
    THREAD->udebug.cur_event = UDEBUG_EVENT_STOP;
 
    _thread_op_end(t);
 
    mutex_lock(&TASK->udebug.lock);
    ipc_answer(&TASK->answerbox, call);
    mutex_unlock(&TASK->udebug.lock);
 
 
    return 0;
}
 
/** Read the list of userspace threads in the current task.
 *
 * The list takes the form of a sequence of thread hashes (i.e. the pointers
 * to thread structures). A buffer of size @a buf_size is allocated and
 * a pointer to it written to @a buffer. The sequence of hashes is written
 * into this buffer.
 *
 * If the sequence is longer than @a buf_size bytes, only as much hashes
 * as can fit are copied. The number of thread hashes copied is stored
 * in @a n.
 *
 * The rationale for having @a buf_size is that this function is only
 * used for servicing the THREAD_READ message, which always specifies
 * a maximum size for the userspace buffer.
 *
 * @param buffer    The buffer for storing thread hashes.
 * @param buf_size  Buffer size in bytes.
 * @param n     The actual number of hashes copied will be stored here.
 */
int udebug_thread_read(void **buffer, size_t buf_size, size_t *n)
{
    thread_t *t;
    link_t *cur;
    unative_t tid;
    unsigned copied_ids;
    ipl_t ipl;
    unative_t *id_buffer;
    int flags;
    size_t max_ids;
 
    LOG("udebug_thread_read()");
 
    /* Allocate a buffer to hold thread IDs */
    id_buffer = malloc(buf_size, 0);
 
    mutex_lock(&TASK->udebug.lock);
 
    /* Verify task state */
    if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {
        mutex_unlock(&TASK->udebug.lock);
        return EINVAL;
    }
 
    ipl = interrupts_disable();
    spinlock_lock(&TASK->lock);
    /* Copy down the thread IDs */
 
    max_ids = buf_size / sizeof(unative_t);
    copied_ids = 0;
 
    /* FIXME: make sure the thread isn't past debug shutdown... */
    for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) {
        /* Do not write past end of buffer */
        if (copied_ids >= max_ids) break;
 
        t = list_get_instance(cur, thread_t, th_link);
 
        spinlock_lock(&t->lock);
        flags = t->flags;
        spinlock_unlock(&t->lock);
 
        /* Not interested in kernel threads. */
        if ((flags & THREAD_FLAG_USPACE) != 0) {
            /* Using thread struct pointer as identification hash */
            tid = (unative_t) t;
            id_buffer[copied_ids++] = tid;
        }
    }
 
    spinlock_unlock(&TASK->lock);
    interrupts_restore(ipl);
 
    mutex_unlock(&TASK->udebug.lock);
 
    *buffer = id_buffer;
    *n = copied_ids * sizeof(unative_t);
 
    return 0;
}
 
/** Read the arguments of a system call.
 *
 * The arguments of the system call being being executed are copied
 * to an allocated buffer and a pointer to it is written to @a buffer.
 * The size of the buffer is exactly such that it can hold the maximum number
 * of system-call arguments.
 *
 * Unless the thread is currently blocked in a SYSCALL_B or SYSCALL_E event,
 * this function will fail with an EINVAL error code.
 *
 * @param buffer    The buffer for storing thread hashes.
 */
int udebug_args_read(thread_t *t, void **buffer)
{
    int rc;
    unative_t *arg_buffer;
 
    /* Prepare a buffer to hold the arguments. */
    arg_buffer = malloc(6 * sizeof(unative_t), 0);
 
    /* On success, this will lock t->udebug.lock. */
    rc = _thread_op_begin(t, false);
    if (rc != EOK) {
        return rc;
    }
 
    /* Additionally we need to verify that we are inside a syscall. */
    if (t->udebug.cur_event != UDEBUG_EVENT_SYSCALL_B &&
        t->udebug.cur_event != UDEBUG_EVENT_SYSCALL_E) {
        _thread_op_end(t);
        return EINVAL;
    }
 
    /* Copy to a local buffer before releasing the lock. */
    memcpy(arg_buffer, t->udebug.syscall_args, 6 * sizeof(unative_t));
 
    _thread_op_end(t);
 
    *buffer = arg_buffer;
    return 0;
}
 
int udebug_regs_read(thread_t *t, void *buffer)
{
    istate_t *state;
    int rc;
 
    LOG("udebug_regs_read()");
 
    /* On success, this will lock t->udebug.lock */
    rc = _thread_op_begin(t, false);
    if (rc != EOK) {
        return rc;
    }
 
    state = t->udebug.uspace_state;
    if (state == NULL) {
        _thread_op_end(t);
        LOG("udebug_regs_read() - istate not available\n");
        return EBUSY;
    }
 
    /* Copy to the allocated buffer */
    memcpy(buffer, state, sizeof(istate_t));
 
    _thread_op_end(t);
 
    LOG("pc = 0x%" PRIp, istate_get_pc((istate_t *) buffer));
 
    return 0;
}
 
int udebug_regs_write(thread_t *t, void *buffer)
{
    int rc;
    istate_t *state;
 
    LOG("udebug_regs_write()\n");
 
    /* Try to change the thread's uspace_state */
 
    /* On success, this will lock t->udebug.lock */
    rc = _thread_op_begin(t, false);
    if (rc != EOK) {
        LOG("error locking thread\n");
        return rc;
    }
 
    state = t->udebug.uspace_state;
    if (state == NULL) {
        _thread_op_end(t);
        LOG("udebug_regs_write() - istate not available\n");
        return EBUSY;
    }
 
    memcpy(t->udebug.uspace_state, buffer, sizeof(istate_t));
 
    _thread_op_end(t);
 
    return 0;
}
 
/** Read the memory of the debugged task.
 *
 * Reads @a n bytes from the address space of the debugged task, starting
 * from @a uspace_addr. The bytes are copied into an allocated buffer
 * and a pointer to it is written into @a buffer.
 *
 * @param uspace_addr   Address from where to start reading.
 * @param n     Number of bytes to read.
 * @param buffer    For storing a pointer to the allocated buffer.
 */
int udebug_mem_read(unative_t uspace_addr, size_t n, void **buffer)
{
    void *data_buffer;
    int rc;
 
    /* Verify task state */
    mutex_lock(&TASK->udebug.lock);
 
    if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {
        mutex_unlock(&TASK->udebug.lock);
        return EBUSY;
    }
 
    data_buffer = malloc(n, 0);
 
    /* NOTE: this is not strictly from a syscall... but that shouldn't
     * be a problem */
    rc = copy_from_uspace(data_buffer, (void *)uspace_addr, n);
    mutex_unlock(&TASK->udebug.lock);
 
    if (rc != 0) return rc;
 
    *buffer = data_buffer;
    return 0;
}
 
int udebug_mem_write(unative_t uspace_addr, void *data, size_t n)
{
    int rc;
 
    LOG("udebug_mem_write()\n");
 
    /* n must be positive */
    if (n < 1)
        return EINVAL;
 
    /* Verify task state */
    mutex_lock(&TASK->udebug.lock);
 
    if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {
        mutex_unlock(&TASK->udebug.lock);
        return EBUSY;
    }
   
    LOG("dst=%u, size=%u\n", uspace_addr, n);
 
    /* NOTE: this is not strictly from a syscall... but that shouldn't
     * be a problem */
//  rc = copy_to_uspace((void *)uspace_addr, data, n);
//  if (rc) return rc;
 
    rc = as_debug_write(uspace_addr, data, n);
   
    LOG("rc=%d\n", rc);
 
    mutex_unlock(&TASK->udebug.lock);
 
    return rc;
}
 
/** @}
 */
 

Rev 4393	Rev 4692
1	/*	1	/*
2	* Copyright (c) 2008 Jiri Svoboda	2	* Copyright (c) 2008 Jiri Svoboda
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup generic	29	/** @addtogroup generic
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file	34	* @file
35	* @brief Udebug operations.	35	* @brief Udebug operations.
36	*	36	*
37	* Udebug operations on tasks and threads are implemented here. The	37	* Udebug operations on tasks and threads are implemented here. The
38	* functions defined here are called from the udebug_ipc module	38	* functions defined here are called from the udebug_ipc module
39	* when servicing udebug IPC messages.	39	* when servicing udebug IPC messages.
40	*/	40	*/
41		41
42	#include <debug.h>	42	#include <debug.h>
43	#include <proc/task.h>	43	#include <proc/task.h>
44	#include <proc/thread.h>	44	#include <proc/thread.h>
45	#include <arch.h>	45	#include <arch.h>
46	#include <errno.h>	46	#include <errno.h>
47	#include <print.h>	47	#include <print.h>
48	#include <syscall/copy.h>	48	#include <syscall/copy.h>
49	#include <ipc/ipc.h>	49	#include <ipc/ipc.h>
50	#include <udebug/udebug.h>	50	#include <udebug/udebug.h>
51	#include <udebug/udebug_ops.h>	51	#include <udebug/udebug_ops.h>
52		52
53	/**	53	/**
54	* Prepare a thread for a debugging operation.	54	* Prepare a thread for a debugging operation.
55	*	55	*
56	* Simply put, return thread t with t->udebug.lock held,	56	* Simply put, return thread t with t->udebug.lock held,
57	* but only if it verifies all conditions.	57	* but only if it verifies all conditions.
58	*	58	*
59	* Specifically, verifies that thread t exists, is a userspace thread,	59	* Specifically, verifies that thread t exists, is a userspace thread,
60	* and belongs to the current task (TASK). Verifies, that the thread	60	* and belongs to the current task (TASK). Verifies, that the thread
61	* is (or is not) go according to being_go (typically false).	61	* is (or is not) go according to being_go (typically false).
62	* It also locks t->udebug.lock, making sure that t->udebug.active	62	* It also locks t->udebug.lock, making sure that t->udebug.active
63	* is true - that the thread is in a valid debugging session.	63	* is true - that the thread is in a valid debugging session.
64	*	64	*
65	* With this verified and the t->udebug.lock mutex held, it is ensured	65	* With this verified and the t->udebug.lock mutex held, it is ensured
66	* that the thread cannot leave the debugging session, let alone cease	66	* that the thread cannot leave the debugging session, let alone cease
67	* to exist.	67	* to exist.
68	*	68	*
69	* In this function, holding the TASK->udebug.lock mutex prevents the	69	* In this function, holding the TASK->udebug.lock mutex prevents the
70	* thread from leaving the debugging session, while relaxing from	70	* thread from leaving the debugging session, while relaxing from
71	* the t->lock spinlock to the t->udebug.lock mutex.	71	* the t->lock spinlock to the t->udebug.lock mutex.
72	*	72	*
73	* @param t Pointer, need not at all be valid.	73	* @param t Pointer, need not at all be valid.
74	* @param being_go Required thread state.	74	* @param being_go Required thread state.
75	*	75	*
76	* Returns EOK if all went well, or an error code otherwise.	76	* Returns EOK if all went well, or an error code otherwise.
77	*/	77	*/
78	static int _thread_op_begin(thread_t *t, bool being_go)	78	static int _thread_op_begin(thread_t *t, bool being_go)
79	{	79	{
80	task_id_t taskid;	80	task_id_t taskid;
81	ipl_t ipl;	81	ipl_t ipl;
82		82
83	taskid = TASK->taskid;	83	taskid = TASK->taskid;
84		84
85	mutex_lock(&TASK->udebug.lock);	85	mutex_lock(&TASK->udebug.lock);
86		86
87	/* thread_exists() must be called with threads_lock held */	87	/* thread_exists() must be called with threads_lock held */
88	ipl = interrupts_disable();	88	ipl = interrupts_disable();
89	spinlock_lock(&threads_lock);	89	spinlock_lock(&threads_lock);
90		90
91	if (!thread_exists(t)) {	91	if (!thread_exists(t)) {
92	spinlock_unlock(&threads_lock);	92	spinlock_unlock(&threads_lock);
93	interrupts_restore(ipl);	93	interrupts_restore(ipl);
94	mutex_unlock(&TASK->udebug.lock);	94	mutex_unlock(&TASK->udebug.lock);
95	return ENOENT;	95	return ENOENT;
96	}	96	}
97		97
98	/* t->lock is enough to ensure the thread's existence */	98	/* t->lock is enough to ensure the thread's existence */
99	spinlock_lock(&t->lock);	99	spinlock_lock(&t->lock);
100	spinlock_unlock(&threads_lock);	100	spinlock_unlock(&threads_lock);
101		101
102	/* Verify that 't' is a userspace thread. */	102	/* Verify that 't' is a userspace thread. */
103	if ((t->flags & THREAD_FLAG_USPACE) == 0) {	103	if ((t->flags & THREAD_FLAG_USPACE) == 0) {
104	/* It's not, deny its existence */	104	/* It's not, deny its existence */
105	spinlock_unlock(&t->lock);	105	spinlock_unlock(&t->lock);
106	interrupts_restore(ipl);	106	interrupts_restore(ipl);
107	mutex_unlock(&TASK->udebug.lock);	107	mutex_unlock(&TASK->udebug.lock);
108	return ENOENT;	108	return ENOENT;
109	}	109	}
110		110
111	/* Verify debugging state. */	111	/* Verify debugging state. */
112	if (t->udebug.active != true) {	112	if (t->udebug.active != true) {
113	/* Not in debugging session or undesired GO state */	113	/* Not in debugging session or undesired GO state */
114	spinlock_unlock(&t->lock);	114	spinlock_unlock(&t->lock);
115	interrupts_restore(ipl);	115	interrupts_restore(ipl);
116	mutex_unlock(&TASK->udebug.lock);	116	mutex_unlock(&TASK->udebug.lock);
117	return ENOENT;	117	return ENOENT;
118	}	118	}
119		119
120	/*	120	/*
121	* Since the thread has active == true, TASK->udebug.lock	121	* Since the thread has active == true, TASK->udebug.lock
122	* is enough to ensure its existence and that active remains	122	* is enough to ensure its existence and that active remains
123	* true.	123	* true.
124	*/	124	*/
125	spinlock_unlock(&t->lock);	125	spinlock_unlock(&t->lock);
126	interrupts_restore(ipl);	126	interrupts_restore(ipl);
127		127
128	/* Only mutex TASK->udebug.lock left. */	128	/* Only mutex TASK->udebug.lock left. */
129		129
130	/* Now verify that the thread belongs to the current task. */	130	/* Now verify that the thread belongs to the current task. */
131	if (t->task != TASK) {	131	if (t->task != TASK) {
132	/* No such thread belonging this task*/	132	/* No such thread belonging this task*/
133	mutex_unlock(&TASK->udebug.lock);	133	mutex_unlock(&TASK->udebug.lock);
134	return ENOENT;	134	return ENOENT;
135	}	135	}
136		136
137	/*	137	/*
138	* Now we need to grab the thread's debug lock for synchronization	138	* Now we need to grab the thread's debug lock for synchronization
139	* of the threads stoppability/stop state.	139	* of the threads stoppability/stop state.
140	*/	140	*/
141	mutex_lock(&t->udebug.lock);	141	mutex_lock(&t->udebug.lock);
142		142
143	/* The big task mutex is no longer needed. */	143	/* The big task mutex is no longer needed. */
144	mutex_unlock(&TASK->udebug.lock);	144	mutex_unlock(&TASK->udebug.lock);
145		145
146	if (t->udebug.go != being_go) {	146	if (t->udebug.go != being_go) {
147	/* Not in debugging session or undesired GO state. */	147	/* Not in debugging session or undesired GO state. */
148	mutex_unlock(&t->udebug.lock);	148	mutex_unlock(&t->udebug.lock);
149	return EINVAL;	149	return EINVAL;
150	}	150	}
151		151
152	/* Only t->udebug.lock left. */	152	/* Only t->udebug.lock left. */
153		153
154	return EOK; /* All went well. */	154	return EOK; /* All went well. */
155	}	155	}
156		156
157	/** End debugging operation on a thread. */	157	/** End debugging operation on a thread. */
158	static void _thread_op_end(thread_t *t)	158	static void _thread_op_end(thread_t *t)
159	{	159	{
160	mutex_unlock(&t->udebug.lock);	160	mutex_unlock(&t->udebug.lock);
161	}	161	}
162		162
163	/** Begin debugging the current task.	163	/** Begin debugging the current task.
164	*	164	*
165	* Initiates a debugging session for the current task (and its threads).	165	* Initiates a debugging session for the current task (and its threads).
166	* When the debugging session has started a reply will be sent to the	166	* When the debugging session has started a reply will be sent to the
167	* UDEBUG_BEGIN call. This may happen immediately in this function if	167	* UDEBUG_BEGIN call. This may happen immediately in this function if
168	* all the threads in this task are stoppable at the moment and in this	168	* all the threads in this task are stoppable at the moment and in this
169	* case the function returns 1.	169	* case the function returns 1.
170	*	170	*
171	* Otherwise the function returns 0 and the reply will be sent as soon as	171	* Otherwise the function returns 0 and the reply will be sent as soon as
172	* all the threads become stoppable (i.e. they can be considered stopped).	172	* all the threads become stoppable (i.e. they can be considered stopped).
173	*	173	*
174	* @param call The BEGIN call we are servicing.	174	* @param call The BEGIN call we are servicing.
175	* @return 0 (OK, but not done yet), 1 (done) or negative error code.	175	* @return 0 (OK, but not done yet), 1 (done) or negative error code.
176	*/	176	*/
177	int udebug_begin(call_t *call)	177	int udebug_begin(call_t *call)
178	{	178	{
179	int reply;	179	int reply;
180		180
181	thread_t *t;	181	thread_t *t;
182	link_t *cur;	182	link_t *cur;
183		183
184	LOG("udebug_begin()\n");	184	LOG("Debugging task %llu", TASK->taskid);
185		-
186	mutex_lock(&TASK->udebug.lock);	185	mutex_lock(&TASK->udebug.lock);
187	LOG("debugging task %llu\n", TASK->taskid);	-
188		186
189	if (TASK->udebug.dt_state != UDEBUG_TS_INACTIVE) {	187	if (TASK->udebug.dt_state != UDEBUG_TS_INACTIVE) {
190	mutex_unlock(&TASK->udebug.lock);	188	mutex_unlock(&TASK->udebug.lock);
191	LOG("udebug_begin(): busy error\n");	-
192		-
193	return EBUSY;	189	return EBUSY;
194	}	190	}
195		191
196	TASK->udebug.dt_state = UDEBUG_TS_BEGINNING;	192	TASK->udebug.dt_state = UDEBUG_TS_BEGINNING;
197	TASK->udebug.begin_call = call;	193	TASK->udebug.begin_call = call;
198	TASK->udebug.debugger = call->sender;	194	TASK->udebug.debugger = call->sender;
199		195
200	if (TASK->udebug.not_stoppable_count == 0) {	196	if (TASK->udebug.not_stoppable_count == 0) {
201	TASK->udebug.dt_state = UDEBUG_TS_ACTIVE;	197	TASK->udebug.dt_state = UDEBUG_TS_ACTIVE;
202	TASK->udebug.begin_call = NULL;	198	TASK->udebug.begin_call = NULL;
203	reply = 1; /* immediate reply */	199	reply = 1; /* immediate reply */
204	} else {	200	} else {
205	reply = 0; /* no reply */	201	reply = 0; /* no reply */
206	}	202	}
207		203
208	/* Set udebug.active on all of the task's userspace threads. */	204	/* Set udebug.active on all of the task's userspace threads. */
209		205
210	for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) {	206	for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) {
211	t = list_get_instance(cur, thread_t, th_link);	207	t = list_get_instance(cur, thread_t, th_link);
212		208
213	mutex_lock(&t->udebug.lock);	209	mutex_lock(&t->udebug.lock);
214	if ((t->flags & THREAD_FLAG_USPACE) != 0)	210	if ((t->flags & THREAD_FLAG_USPACE) != 0)
215	t->udebug.active = true;	211	t->udebug.active = true;
216	mutex_unlock(&t->udebug.lock);	212	mutex_unlock(&t->udebug.lock);
217	}	213	}
218		214
219	mutex_unlock(&TASK->udebug.lock);	215	mutex_unlock(&TASK->udebug.lock);
220		-
221	LOG("udebug_begin() done (%s)\n",	-
222	reply ? "reply" : "stoppability wait");	-
223		-
224	return reply;	216	return reply;
225	}	217	}
226		218
227	/** Finish debugging the current task.	219	/** Finish debugging the current task.
228	*	220	*
229	* Closes the debugging session for the current task.	221	* Closes the debugging session for the current task.
230	* @return Zero on success or negative error code.	222	* @return Zero on success or negative error code.
231	*/	223	*/
232	int udebug_end(void)	224	int udebug_end(void)
233	{	225	{
234	int rc;	226	int rc;
235		227
236	LOG("udebug_end()\n");	228	LOG("Task %" PRIu64, TASK->taskid);
237		229
238	mutex_lock(&TASK->udebug.lock);	230	mutex_lock(&TASK->udebug.lock);
239	LOG("task %" PRIu64 "\n", TASK->taskid);	-
240		-
241	rc = udebug_task_cleanup(TASK);	231	rc = udebug_task_cleanup(TASK);
242		-
243	mutex_unlock(&TASK->udebug.lock);	232	mutex_unlock(&TASK->udebug.lock);
244		233
245	return rc;	234	return rc;
246	}	235	}
247		236
248	/** Set the event mask.	237	/** Set the event mask.
249	*	238	*
250	* Sets the event mask that determines which events are enabled.	239	* Sets the event mask that determines which events are enabled.
251	*	240	*
252	* @param mask Or combination of events that should be enabled.	241	* @param mask Or combination of events that should be enabled.
253	* @return Zero on success or negative error code.	242	* @return Zero on success or negative error code.
254	*/	243	*/
255	int udebug_set_evmask(udebug_evmask_t mask)	244	int udebug_set_evmask(udebug_evmask_t mask)
256	{	245	{
257	LOG("udebug_set_mask()\n");	246	LOG("mask = 0x%x", mask);
258		247
259	mutex_lock(&TASK->udebug.lock);	248	mutex_lock(&TASK->udebug.lock);
260		249
261	if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {	250	if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {
262	mutex_unlock(&TASK->udebug.lock);	251	mutex_unlock(&TASK->udebug.lock);
263	LOG("udebug_set_mask(): not active debuging session\n");	-
264		-
265	return EINVAL;	252	return EINVAL;
266	}	253	}
267		254
268	TASK->udebug.evmask = mask;	255	TASK->udebug.evmask = mask;
269		-
270	mutex_unlock(&TASK->udebug.lock);	256	mutex_unlock(&TASK->udebug.lock);
271		257
272	return 0;	258	return 0;
273	}	259	}
274		260
275	/** Give thread GO.	261	/** Give thread GO.
276	*	262	*
277	* Upon recieving a go message, the thread is given GO. Being GO	263	* Upon recieving a go message, the thread is given GO. Being GO
278	* means the thread is allowed to execute userspace code (until	264	* means the thread is allowed to execute userspace code (until
279	* a debugging event or STOP occurs, at which point the thread loses GO.	265	* a debugging event or STOP occurs, at which point the thread loses GO.
280	*	266	*
281	* @param t The thread to operate on (unlocked and need not be valid).	267	* @param t The thread to operate on (unlocked and need not be valid).
282	* @param call The GO call that we are servicing.	268	* @param call The GO call that we are servicing.
283	*/	269	*/
284	int udebug_go(thread_t t, call_t call)	270	int udebug_go(thread_t t, call_t call)
285	{	271	{
286	int rc;	272	int rc;
287		273
288	/* On success, this will lock t->udebug.lock. */	274	/* On success, this will lock t->udebug.lock. */
289	rc = _thread_op_begin(t, false);	275	rc = _thread_op_begin(t, false);
290	if (rc != EOK) {	276	if (rc != EOK) {
291	return rc;	277	return rc;
292	}	278	}
293		279
294	t->udebug.go_call = call;	280	t->udebug.go_call = call;
295	t->udebug.go = true;	281	t->udebug.go = true;
296	t->udebug.cur_event = 0; /* none */	282	t->udebug.cur_event = 0; /* none */
297		283
298	/*	284	/*
299	* Neither t's lock nor threads_lock may be held during wakeup.	285	* Neither t's lock nor threads_lock may be held during wakeup.
300	*/	286	*/
301	waitq_wakeup(&t->udebug.go_wq, WAKEUP_FIRST);	287	waitq_wakeup(&t->udebug.go_wq, WAKEUP_FIRST);
302		288
303	_thread_op_end(t);	289	_thread_op_end(t);
304		290
305	return 0;	291	return 0;
306	}	292	}
307		293
308	/** Stop a thread (i.e. take its GO away)	294	/** Stop a thread (i.e. take its GO away)
309	*	295	*
310	* Generates a STOP event as soon as the thread becomes stoppable (i.e.	296	* Generates a STOP event as soon as the thread becomes stoppable (i.e.
311	* can be considered stopped).	297	* can be considered stopped).
312	*	298	*
313	* @param t The thread to operate on (unlocked and need not be valid).	299	* @param t The thread to operate on (unlocked and need not be valid).
314	* @param call The GO call that we are servicing.	300	* @param call The GO call that we are servicing.
315	*/	301	*/
316	int udebug_stop(thread_t t, call_t call)	302	int udebug_stop(thread_t t, call_t call)
317	{	303	{
318	int rc;	304	int rc;
319		305
320	LOG("udebug_stop()\n");	306	LOG("udebug_stop()");
321		307
322	/*	308	/*
323	* On success, this will lock t->udebug.lock. Note that this makes sure	309	* On success, this will lock t->udebug.lock. Note that this makes sure
324	* the thread is not stopped.	310	* the thread is not stopped.
325	*/	311	*/
326	rc = _thread_op_begin(t, true);	312	rc = _thread_op_begin(t, true);
327	if (rc != EOK) {	313	if (rc != EOK) {
328	return rc;	314	return rc;
329	}	315	}
330		316
331	/* Take GO away from the thread. */	317	/* Take GO away from the thread. */
332	t->udebug.go = false;	318	t->udebug.go = false;
333		319
334	if (t->udebug.stoppable != true) {	320	if (t->udebug.stoppable != true) {
335	/* Answer will be sent when the thread becomes stoppable. */	321	/* Answer will be sent when the thread becomes stoppable. */
336	_thread_op_end(t);	322	_thread_op_end(t);
337	return 0;	323	return 0;
338	}	324	}
339		325
340	/*	326	/*
341	* Answer GO call.	327	* Answer GO call.
342	*/	328	*/
343	LOG("udebug_stop - answering go call\n");	-
344		329
345	/* Make sure nobody takes this call away from us. */	330	/* Make sure nobody takes this call away from us. */
346	call = t->udebug.go_call;	331	call = t->udebug.go_call;
347	t->udebug.go_call = NULL;	332	t->udebug.go_call = NULL;
348		333
349	IPC_SET_RETVAL(call->data, 0);	334	IPC_SET_RETVAL(call->data, 0);
350	IPC_SET_ARG1(call->data, UDEBUG_EVENT_STOP);	335	IPC_SET_ARG1(call->data, UDEBUG_EVENT_STOP);
351	LOG("udebug_stop/ipc_answer\n");	-
352		336
353	THREAD->udebug.cur_event = UDEBUG_EVENT_STOP;	337	THREAD->udebug.cur_event = UDEBUG_EVENT_STOP;
354		338
355	_thread_op_end(t);	339	_thread_op_end(t);
356		340
357	mutex_lock(&TASK->udebug.lock);	341	mutex_lock(&TASK->udebug.lock);
358	ipc_answer(&TASK->answerbox, call);	342	ipc_answer(&TASK->answerbox, call);
359	mutex_unlock(&TASK->udebug.lock);	343	mutex_unlock(&TASK->udebug.lock);
360		344
361	LOG("udebog_stop/done\n");	-
362	return 0;	345	return 0;
363	}	346	}
364		347
365	/** Read the list of userspace threads in the current task.	348	/** Read the list of userspace threads in the current task.
366	*	349	*
367	* The list takes the form of a sequence of thread hashes (i.e. the pointers	350	* The list takes the form of a sequence of thread hashes (i.e. the pointers
368	* to thread structures). A buffer of size @a buf_size is allocated and	351	* to thread structures). A buffer of size @a buf_size is allocated and
369	* a pointer to it written to @a buffer. The sequence of hashes is written	352	* a pointer to it written to @a buffer. The sequence of hashes is written
370	* into this buffer.	353	* into this buffer.
371	*	354	*
372	* If the sequence is longer than @a buf_size bytes, only as much hashes	355	* If the sequence is longer than @a buf_size bytes, only as much hashes
373	* as can fit are copied. The number of thread hashes copied is stored	356	* as can fit are copied. The number of thread hashes copied is stored
374	* in @a n.	357	* in @a n.
375	*	358	*
376	* The rationale for having @a buf_size is that this function is only	359	* The rationale for having @a buf_size is that this function is only
377	* used for servicing the THREAD_READ message, which always specifies	360	* used for servicing the THREAD_READ message, which always specifies
378	* a maximum size for the userspace buffer.	361	* a maximum size for the userspace buffer.
379	*	362	*
380	* @param buffer The buffer for storing thread hashes.	363	* @param buffer The buffer for storing thread hashes.
381	* @param buf_size Buffer size in bytes.	364	* @param buf_size Buffer size in bytes.
382	* @param n The actual number of hashes copied will be stored here.	365	* @param n The actual number of hashes copied will be stored here.
383	*/	366	*/
384	int udebug_thread_read(void *buffer, size_t buf_size, size_t n)	367	int udebug_thread_read(void *buffer, size_t buf_size, size_t n)
385	{	368	{
386	thread_t *t;	369	thread_t *t;
387	link_t *cur;	370	link_t *cur;
388	unative_t tid;	371	unative_t tid;
389	unsigned copied_ids;	372	unsigned copied_ids;
390	ipl_t ipl;	373	ipl_t ipl;
391	unative_t *id_buffer;	374	unative_t *id_buffer;
392	int flags;	375	int flags;
393	size_t max_ids;	376	size_t max_ids;
394		377
395	LOG("udebug_thread_read()\n");	378	LOG("udebug_thread_read()");
396		379
397	/* Allocate a buffer to hold thread IDs */	380	/* Allocate a buffer to hold thread IDs */
398	id_buffer = malloc(buf_size, 0);	381	id_buffer = malloc(buf_size, 0);
399		382
400	mutex_lock(&TASK->udebug.lock);	383	mutex_lock(&TASK->udebug.lock);
401		384
402	/* Verify task state */	385	/* Verify task state */
403	if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {	386	if (TASK->udebug.dt_state != UDEBUG_TS_ACTIVE) {
404	mutex_unlock(&TASK->udebug.lock);	387	mutex_unlock(&TASK->udebug.lock);
405	return EINVAL;	388	return EINVAL;
406	}	389	}
407		390
408	ipl = interrupts_disable();	391	ipl = interrupts_disable();
409	spinlock_lock(&TASK->lock);	392	spinlock_lock(&TASK->lock);
410	/* Copy down the thread IDs */	393	/* Copy down the thread IDs */
411		394
412	max_ids = buf_size / sizeof(unative_t);	395	max_ids = buf_size / sizeof(unative_t);
413	copied_ids = 0;	396	copied_ids = 0;
414		397
415	/* FIXME: make sure the thread isn't past debug shutdown... */	398	/* FIXME: make sure the thread isn't past debug shutdown... */
416	for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) {	399	for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) {
417	/* Do not write past end of buffer */	400	/* Do not write past end of buffer */
418	if (copied_ids >= max_ids) break;	401	if (copied_ids >= max_ids) break;
419		402
420	t = list_get_instance(cur, thread_t, th_link);	403	t = list_get_instance(cur, thread_t, th_link);
421		404
422	spinlock_lock(&t->lock);	405	spinlock_lock(&t->lock);
423	flags = t->flags;	406	flags = t->flags;
424	spinlock_unlock(&t->lock);	407	spinlock_unlock(&t->lock);
425		408
426	/* Not interested in kernel threads. */	409	/* Not interested in kernel threads. */
427	if ((flags & THREAD_FLAG_USPACE) != 0) {	410	if ((flags & THREAD_FLAG_USPACE) != 0) {
428	/* Using thread struct pointer as identification hash */	411	/* Using thread struct pointer as identification hash */
429	tid = (unative_t) t;	412	tid = (unative_t) t;
430	id_buffer[copied_ids++] = tid;	413	id_buffer[copied_ids++] = tid;
431	}	414	}
432	}	415	}
433		416
434	spinlock_unlock(&TASK->lock);	417	spinlock_unlock(&TASK->lock);
435	interrupts_restore(ipl);	418	interrupts_restore(ipl);
436		419
437	mutex_unlock(&TASK->udebug.lock);	420	mutex_unlock(&TASK->udebug.lock);
438		421
439	*buffer = id_buffer;	422	*buffer = id_buffer;
440	n = copied_ids sizeof(unative_t);	423	n = copied_ids sizeof(unative_t);
441		424
442	return 0;	425	return 0;
443	}	426	}
444		427
445	/** Read the arguments of a system call.	428	/** Read the arguments of a system call.
446	*	429	*
447	* The arguments of the system call being being executed are copied	430	* The arguments of the system call being being executed are copied
448	* to an allocated buffer and a pointer to it is written to @a buffer.	431	* to an allocated buffer and a pointer to it is written to @a buffer.
449	* The size of the buffer is exactly such that it can hold the maximum number	432	* The size of the buffer is exactly such that it can hold the maximum number
450	* of system-call arguments.	433	* of system-call arguments.
451	*	434	*
452	* Unless the thread is currently blocked in a SYSCALL_B or SYSCALL_E event,	435	* Unless the thread is currently blocked in a SYSCALL_B or SYSCALL_E event,
453	* this function will fail with an EINVAL error code.	436	* this function will fail with an EINVAL error code.
454	*	437	*
455	* @param buffer The buffer for storing thread hashes.	438	* @param buffer The buffer for storing thread hashes.
456	*/	439	*/
457	int udebug_args_read(thread_t t, void *buffer)	440	int udebug_args_read(thread_t t, void *buffer)
458	{	441	{
459	int rc;	442	int rc;
460	unative_t *arg_buffer;	443	unative_t *arg_buffer;
461		444
462	/* Prepare a buffer to hold the arguments. */	445	/* Prepare a buffer to hold the arguments. */
463	arg_buffer = malloc(6 * sizeof(unative_t), 0);	446	arg_buffer = malloc(6 * sizeof(unative_t), 0);
464		447
465	/* On success, this will lock t->udebug.lock. */	448	/* On success, this will lock t->udebug.lock. */
466	rc = _thread_op_begin(t, false);	449	rc = _thread_op_begin(t, false);
467	if (rc != EOK) {	450	if (rc != EOK) {
468	return rc;	451	return rc;
469	}	452	}
470		453
471	/* Additionally we need to verify that we are inside a syscall. */	454	/* Additionally we need to verify that we are inside a syscall. */
472	if (t->udebug.cur_event != UDEBUG_EVENT_SYSCALL_B &&	455	if (t->udebug.cur_event != UDEBUG_EVENT_SYSCALL_B &&
473	t->udebug.cur_event != UDEBUG_EVENT_SYSCALL_E) {	456	t->udebug.cur_event != UDEBUG_EVENT_SYSCALL_E) {
474	_thread_op_end(t);	457	_thread_op_end(t);
475	return EINVAL;	458	return EINVAL;
476	}	459	}
477		460
478	/* Copy to a local buffer before releasing the lock. */	461	/* Copy to a local buffer before releasing the lock. */
479	memcpy(arg_buffer, t->udebug.syscall_args, 6 * sizeof(unative_t));	462	memcpy(arg_buffer, t->udebug.syscall_args, 6 * sizeof(unative_t));
480		463
481	_thread_op_end(t);	464	_thread_op_end(t);
482		465
483	*buffer = arg_buffer;	466	*buffer = arg_buffer;
484	return 0;	467	return 0;
485	}	468	}
486		469
487	int udebug_regs_read(thread_t t, void buffer)	470	int udebug_regs_read(thread_t t, void buffer)
488	{	471	{
489	istate_t *state;	472	istate_t *state;
490	int rc;	473	int rc;
491		474
492	LOG("udebug_regs_read()");	475	LOG("udebug_regs_read()");
493		476
494	/* On success, this will lock t->udebug.lock */	477	/* On success, this will lock t->udebug.lock */
495	rc = _thread_op_begin(t, false);	478	rc = _thread_op_begin(t, false);
496	if (rc != EOK) {	479	if (rc != EOK) {
497	return rc;	480	return rc;
498	}	481	}
499		482
500	state = t->udebug.uspace_state;	483	state = t->udebug.uspace_state;

Subversion Repositories HelenOS

(root)/branches/tracing/kernel/generic/src/udebug/udebug_ops.c – Rev 4393 → 4692