int rt_buffer_inquire(RT_BUFFER *bf, RT_BUFFER_INFO *info)
{
int ret = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
bf = xeno_h2obj_validate(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
if (bf == NULL) {
ret = xeno_handle_error(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
goto unlock_and_exit;
}
strcpy(info->name, bf->name);
info->iwaiters = xnsynch_nsleepers(&bf->isynch_base);
info->owaiters = xnsynch_nsleepers(&bf->osynch_base);
info->totalmem = bf->bufsz;
info->availmem = bf->bufsz - bf->fillsz;
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return ret;
}
int rt_cond_signal(RT_COND *cond)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
cond = xeno_h2obj_validate(cond, XENO_COND_MAGIC, RT_COND);
if (!cond) {
err = xeno_handle_error(cond, XENO_COND_MAGIC, RT_COND);
goto unlock_and_exit;
}
if (thread2rtask(xnsynch_wakeup_one_sleeper(&cond->synch_base)) != NULL) {
xnsynch_set_owner(&cond->synch_base, NULL); /* No ownership to track. */
xnpod_schedule();
}
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_buffer_clear(RT_BUFFER *bf)
{
int ret = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
bf = xeno_h2obj_validate(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
if (bf == NULL) {
ret = xeno_handle_error(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
goto unlock_and_exit;
}
bf->wroff = 0;
bf->rdoff = 0;
bf->fillsz = 0;
if (xnsynch_flush(&bf->osynch_base, 0) == XNSYNCH_RESCHED)
xnpod_schedule();
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return ret;
}
int rt_event_clear(RT_EVENT *event, unsigned long mask, unsigned long *mask_r)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
event = xeno_h2obj_validate(event, XENO_EVENT_MAGIC, RT_EVENT);
if (!event) {
err = xeno_handle_error(event, XENO_EVENT_MAGIC, RT_EVENT);
goto unlock_and_exit;
}
if (mask_r)
*mask_r = event->value;
/* Clear the flags. */
event->value &= ~mask;
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_heap_inquire(RT_HEAP *heap, RT_HEAP_INFO *info)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
heap = xeno_h2obj_validate(heap, XENO_HEAP_MAGIC, RT_HEAP);
if (!heap) {
err = xeno_handle_error(heap, XENO_HEAP_MAGIC, RT_HEAP);
goto unlock_and_exit;
}
strcpy(info->name, heap->name);
info->nwaiters = xnsynch_nsleepers(&heap->synch_base);
info->heapsize = heap->csize;
info->usablemem = xnheap_usable_mem(&heap->heap_base);
info->usedmem = xnheap_used_mem(&heap->heap_base);
info->mode = heap->mode;
#ifdef __XENO_SIM__
info->phys_addr = 0;
#else
info->phys_addr = (heap->mode & H_SINGLE) ? virt_to_phys(heap->sba):0;
#endif
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_cond_wait_epilogue(RT_MUTEX *mutex, unsigned lockcnt)
{
int err;
spl_t s;
xnlock_get_irqsave(&nklock, s);
mutex = xeno_h2obj_validate(mutex, XENO_MUTEX_MAGIC, RT_MUTEX);
if (!mutex) {
err = xeno_handle_error(mutex, XENO_MUTEX_MAGIC, RT_MUTEX);
goto unlock_and_exit;
}
err = rt_mutex_acquire(mutex, TM_INFINITE);
if(!err)
mutex->lockcnt = lockcnt; /* Adjust lockcnt */
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_sem_v(RT_SEM *sem)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
sem = xeno_h2obj_validate(sem, XENO_SEM_MAGIC, RT_SEM);
if (!sem) {
err = xeno_handle_error(sem, XENO_SEM_MAGIC, RT_SEM);
goto unlock_and_exit;
}
if (xnsynch_wakeup_one_sleeper(&sem->synch_base) != NULL)
xnpod_schedule();
else if (!(sem->mode & S_PULSE))
sem->count++;
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_sem_broadcast(RT_SEM *sem)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
sem = xeno_h2obj_validate(sem, XENO_SEM_MAGIC, RT_SEM);
if (!sem) {
err = xeno_handle_error(sem, XENO_SEM_MAGIC, RT_SEM);
goto unlock_and_exit;
}
if (xnsynch_flush(&sem->synch_base, 0) == XNSYNCH_RESCHED)
xnpod_schedule();
sem->count = 0;
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_heap_free(RT_HEAP *heap, void *block)
{
int err, nwake;
spl_t s;
if (block == NULL)
return -EINVAL;
xnlock_get_irqsave(&nklock, s);
heap = xeno_h2obj_validate(heap, XENO_HEAP_MAGIC, RT_HEAP);
if (!heap) {
err = xeno_handle_error(heap, XENO_HEAP_MAGIC, RT_HEAP);
goto unlock_and_exit;
}
if (heap->mode & H_SINGLE) { /* No-op in single-block mode. */
err = 0;
goto unlock_and_exit;
}
err = xnheap_free(&heap->heap_base, block);
if (!err && xnsynch_nsleepers(&heap->synch_base) > 0) {
xnpholder_t *holder, *nholder;
nholder = getheadpq(xnsynch_wait_queue(&heap->synch_base));
nwake = 0;
while ((holder = nholder) != NULL) {
RT_TASK *sleeper =
thread2rtask(link2thread(holder, plink));
void *block;
block = xnheap_alloc(&heap->heap_base,
sleeper->wait_args.heap.size);
if (block) {
nholder =
xnsynch_wakeup_this_sleeper(&heap->
synch_base,
holder);
sleeper->wait_args.heap.block = block;
nwake++;
} else
nholder =
nextpq(xnsynch_wait_queue
(&heap->synch_base), holder);
}
if (nwake > 0)
xnpod_schedule();
}
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_heap_delete_inner(RT_HEAP *heap, void __user *mapaddr)
{
int err = 0;
spl_t s;
if (!xnpod_root_p())
return -EPERM;
xnlock_get_irqsave(&nklock, s);
heap = xeno_h2obj_validate(heap, XENO_HEAP_MAGIC, RT_HEAP);
if (!heap) {
err = xeno_handle_error(heap, XENO_HEAP_MAGIC, RT_HEAP);
xnlock_put_irqrestore(&nklock, s);
return err;
}
xeno_mark_deleted(heap);
/* Get out of the nklocked section before releasing the heap
memory, since we are about to invoke Linux kernel
services. */
xnlock_put_irqrestore(&nklock, s);
/*
* The heap descriptor has been marked as deleted before we
* released the superlock thus preventing any sucessful
* subsequent calls of rt_heap_delete(), so now we can
* actually destroy it safely.
*/
#ifdef CONFIG_XENO_OPT_PERVASIVE
if (heap->mode & H_MAPPABLE)
err = xnheap_destroy_mapped(&heap->heap_base,
__heap_post_release, mapaddr);
else
#endif /* CONFIG_XENO_OPT_PERVASIVE */
err = xnheap_destroy(&heap->heap_base, &__heap_flush_private, NULL);
xnlock_get_irqsave(&nklock, s);
if (err)
heap->magic = XENO_HEAP_MAGIC;
else if (!(heap->mode & H_MAPPABLE))
__heap_post_release(&heap->heap_base);
xnlock_put_irqrestore(&nklock, s);
return err;
}
static int vfile_rewind(struct xnvfile_snapshot_iterator *it)
{
struct vfile_priv *priv = xnvfile_iterator_priv(it);
RT_COND *cond = xnvfile_priv(it->vfile);
cond = xeno_h2obj_validate(cond, XENO_COND_MAGIC, RT_COND);
if (cond == NULL)
return -EIDRM;
priv->curr = getheadpq(xnsynch_wait_queue(&cond->synch_base));
return xnsynch_nsleepers(&cond->synch_base);
}
static int vfile_rewind(struct xnvfile_snapshot_iterator *it)
{
struct vfile_priv *priv = xnvfile_iterator_priv(it);
RT_EVENT *event = xnvfile_priv(it->vfile);
event = xeno_h2obj_validate(event, XENO_EVENT_MAGIC, RT_EVENT);
if (event == NULL)
return -EIDRM;
priv->curr = getheadpq(xnsynch_wait_queue(&event->synch_base));
priv->value = event->value;
return xnsynch_nsleepers(&event->synch_base);
}
int rt_event_signal(RT_EVENT *event, unsigned long mask)
{
xnpholder_t *holder, *nholder;
int err = 0, resched = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
event = xeno_h2obj_validate(event, XENO_EVENT_MAGIC, RT_EVENT);
if (!event) {
err = xeno_handle_error(event, XENO_EVENT_MAGIC, RT_EVENT);
goto unlock_and_exit;
}
/* Post the flags. */
event->value |= mask;
/* And wakeup any sleeper having its request fulfilled. */
nholder = getheadpq(xnsynch_wait_queue(&event->synch_base));
while ((holder = nholder) != NULL) {
RT_TASK *sleeper = thread2rtask(link2thread(holder, plink));
int mode = sleeper->wait_args.event.mode;
unsigned long bits = sleeper->wait_args.event.mask;
if (((mode & EV_ANY) && (bits & event->value) != 0) ||
(!(mode & EV_ANY) && ((bits & event->value) == bits))) {
sleeper->wait_args.event.mask = (bits & event->value);
nholder =
xnsynch_wakeup_this_sleeper(&event->synch_base,
holder);
resched = 1;
} else
nholder =
nextpq(xnsynch_wait_queue(&event->synch_base),
holder);
}
if (resched)
xnpod_schedule();
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_sem_p_inner(RT_SEM *sem, xntmode_t timeout_mode, RTIME timeout)
{
xnflags_t info;
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
sem = xeno_h2obj_validate(sem, XENO_SEM_MAGIC, RT_SEM);
if (!sem) {
err = xeno_handle_error(sem, XENO_SEM_MAGIC, RT_SEM);
goto unlock_and_exit;
}
if (timeout == TM_NONBLOCK) {
if (sem->count > 0)
sem->count--;
else
err = -EWOULDBLOCK;
goto unlock_and_exit;
}
if (xnpod_unblockable_p()) {
err = -EPERM;
goto unlock_and_exit;
}
if (sem->count > 0)
--sem->count;
else {
info = xnsynch_sleep_on(&sem->synch_base,
timeout, timeout_mode);
if (info & XNRMID)
err = -EIDRM; /* Semaphore deleted while pending. */
else if (info & XNTIMEO)
err = -ETIMEDOUT; /* Timeout. */
else if (info & XNBREAK)
err = -EINTR; /* Unblocked. */
}
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
static int vfile_rewind(struct xnvfile_snapshot_iterator *it)
{
struct vfile_priv *priv = xnvfile_iterator_priv(it);
RT_HEAP *heap = xnvfile_priv(it->vfile);
heap = xeno_h2obj_validate(heap, XENO_HEAP_MAGIC, RT_HEAP);
if (heap == NULL)
return -EIDRM;
priv->curr = getheadpq(xnsynch_wait_queue(&heap->synch_base));
priv->mode = heap->mode;
priv->usable_mem = xnheap_usable_mem(&heap->heap_base);
priv->used_mem = xnheap_used_mem(&heap->heap_base);
priv->nrmaps = heap->heap_base.archdep.numaps;
return xnsynch_nsleepers(&heap->synch_base);
}
int rt_heap_delete_inner(RT_HEAP *heap, void __user *mapaddr)
{
int err;
spl_t s;
if (!xnpod_root_p())
return -EPERM;
xnlock_get_irqsave(&nklock, s);
heap = xeno_h2obj_validate(heap, XENO_HEAP_MAGIC, RT_HEAP);
if (!heap) {
err = xeno_handle_error(heap, XENO_HEAP_MAGIC, RT_HEAP);
xnlock_put_irqrestore(&nklock, s);
return err;
}
xeno_mark_deleted(heap);
/* Get out of the nklocked section before releasing the heap
memory, since we are about to invoke Linux kernel
services. */
xnlock_put_irqrestore(&nklock, s);
/*
* The heap descriptor has been marked as deleted before we
* released the superlock thus preventing any subsequent call
* to rt_heap_delete() to succeed, so now we can actually
* destroy it safely.
*/
#ifndef __XENO_SIM__
if (heap->mode & H_MAPPABLE)
xnheap_destroy_mapped(&heap->heap_base,
__heap_post_release, mapaddr);
else
#endif
{
xnheap_destroy(&heap->heap_base, &__heap_flush_private, NULL);
__heap_post_release(&heap->heap_base);
}
return 0;
}
static int vfile_rewind(struct xnvfile_snapshot_iterator *it)
{
struct vfile_priv *priv = xnvfile_iterator_priv(it);
RT_BUFFER *bf = xnvfile_priv(it->vfile);
bf = xeno_h2obj_validate(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
if (bf == NULL)
return -EIDRM;
/* Start collecting records from the input wait side. */
priv->curr = getheadpq(xnsynch_wait_queue(&bf->isynch_base));
priv->mode = bf->mode;
priv->bufsz = bf->bufsz;
priv->fillsz = bf->fillsz;
priv->input = 1;
return xnsynch_nsleepers(&bf->isynch_base) +
xnsynch_nsleepers(&bf->osynch_base);
}
int rt_intr_delete(RT_INTR *intr)
{
int err = 0, rc = XNSYNCH_DONE;
spl_t s;
if (xnpod_asynch_p())
return -EPERM;
xnlock_get_irqsave(&nklock, s);
intr = xeno_h2obj_validate(intr, XENO_INTR_MAGIC, RT_INTR);
if (!intr) {
err = xeno_handle_error(intr, XENO_INTR_MAGIC, RT_INTR);
xnlock_put_irqrestore(&nklock, s);
return err;
}
removeq(intr->rqueue, &intr->rlink);
#ifdef CONFIG_XENO_OPT_PERVASIVE
rc = xnsynch_destroy(&intr->synch_base);
#endif /* CONFIG_XENO_OPT_PERVASIVE */
if (intr->handle)
xnregistry_remove(intr->handle);
xeno_mark_deleted(intr);
xnlock_put_irqrestore(&nklock, s);
err = xnintr_destroy(&intr->intr_base);
if (rc == XNSYNCH_RESCHED)
/* Some task has been woken up as a result of the deletion:
reschedule now. */
xnpod_schedule();
return err;
}
int rt_intr_disable(RT_INTR *intr)
{
int err;
spl_t s;
xnlock_get_irqsave(&nklock, s);
intr = xeno_h2obj_validate(intr, XENO_INTR_MAGIC, RT_INTR);
if (!intr) {
err = xeno_handle_error(intr, XENO_INTR_MAGIC, RT_INTR);
goto unlock_and_exit;
}
err = xnintr_disable(&intr->intr_base);
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_event_delete(RT_EVENT *event)
{
int err = 0, rc;
spl_t s;
if (xnpod_asynch_p())
return -EPERM;
xnlock_get_irqsave(&nklock, s);
event = xeno_h2obj_validate(event, XENO_EVENT_MAGIC, RT_EVENT);
if (!event) {
err = xeno_handle_error(event, XENO_EVENT_MAGIC, RT_EVENT);
goto unlock_and_exit;
}
removeq(event->rqueue, &event->rlink);
rc = xnsynch_destroy(&event->synch_base);
#ifdef CONFIG_XENO_OPT_REGISTRY
if (event->handle)
xnregistry_remove(event->handle);
#endif /* CONFIG_XENO_OPT_REGISTRY */
xeno_mark_deleted(event);
if (rc == XNSYNCH_RESCHED)
/* Some task has been woken up as a result of the deletion:
reschedule now. */
xnpod_schedule();
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_buffer_delete(RT_BUFFER *bf)
{
int ret = 0, resched;
spl_t s;
if (xnpod_asynch_p())
return -EPERM;
xnlock_get_irqsave(&nklock, s);
bf = xeno_h2obj_validate(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
if (bf == NULL) {
ret = xeno_handle_error(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
goto unlock_and_exit;
}
xnarch_free_host_mem(bf->bufmem, bf->bufsz);
removeq(bf->rqueue, &bf->rlink);
resched = xnsynch_destroy(&bf->isynch_base) == XNSYNCH_RESCHED;
resched += xnsynch_destroy(&bf->osynch_base) == XNSYNCH_RESCHED;
if (bf->handle)
xnregistry_remove(bf->handle);
xeno_mark_deleted(bf);
if (resched)
/*
* Some task has been woken up as a result of the
* deletion: reschedule now.
*/
xnpod_schedule();
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return ret;
}
int rt_cond_inquire(RT_COND *cond, RT_COND_INFO *info)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
cond = xeno_h2obj_validate(cond, XENO_COND_MAGIC, RT_COND);
if (!cond) {
err = xeno_handle_error(cond, XENO_COND_MAGIC, RT_COND);
goto unlock_and_exit;
}
strcpy(info->name, cond->name);
info->nwaiters = xnsynch_nsleepers(&cond->synch_base);
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_cond_broadcast(RT_COND *cond)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
cond = xeno_h2obj_validate(cond, XENO_COND_MAGIC, RT_COND);
if (!cond) {
err = xeno_handle_error(cond, XENO_COND_MAGIC, RT_COND);
goto unlock_and_exit;
}
if (xnsynch_flush(&cond->synch_base, 0) == XNSYNCH_RESCHED)
xnpod_schedule();
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_sem_delete(RT_SEM *sem)
{
int err = 0, rc;
spl_t s;
if (xnpod_asynch_p())
return -EPERM;
xnlock_get_irqsave(&nklock, s);
sem = xeno_h2obj_validate(sem, XENO_SEM_MAGIC, RT_SEM);
if (!sem) {
err = xeno_handle_error(sem, XENO_SEM_MAGIC, RT_SEM);
goto unlock_and_exit;
}
removeq(sem->rqueue, &sem->rlink);
rc = xnsynch_destroy(&sem->synch_base);
if (sem->handle)
xnregistry_remove(sem->handle);
xeno_mark_deleted(sem);
if (rc == XNSYNCH_RESCHED)
/* Some task has been woken up as a result of the deletion:
reschedule now. */
xnpod_schedule();
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_intr_inquire(RT_INTR *intr, RT_INTR_INFO *info)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
intr = xeno_h2obj_validate(intr, XENO_INTR_MAGIC, RT_INTR);
if (!intr) {
err = xeno_handle_error(intr, XENO_INTR_MAGIC, RT_INTR);
goto unlock_and_exit;
}
strcpy(info->name, intr->name);
info->hits = __intr_get_hits(intr);
info->irq = intr->intr_base.irq;
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_event_inquire(RT_EVENT *event, RT_EVENT_INFO *info)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
event = xeno_h2obj_validate(event, XENO_EVENT_MAGIC, RT_EVENT);
if (!event) {
err = xeno_handle_error(event, XENO_EVENT_MAGIC, RT_EVENT);
goto unlock_and_exit;
}
strcpy(info->name, event->name);
info->value = event->value;
info->nwaiters = xnsynch_nsleepers(&event->synch_base);
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_sem_inquire(RT_SEM *sem, RT_SEM_INFO *info)
{
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
sem = xeno_h2obj_validate(sem, XENO_SEM_MAGIC, RT_SEM);
if (!sem) {
err = xeno_handle_error(sem, XENO_SEM_MAGIC, RT_SEM);
goto unlock_and_exit;
}
strcpy(info->name, sem->name);
info->count = sem->count;
info->nwaiters = xnsynch_nsleepers(&sem->synch_base);
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_event_wait_inner(RT_EVENT *event,
unsigned long mask,
unsigned long *mask_r,
int mode, xntmode_t timeout_mode, RTIME timeout)
{
RT_TASK *task;
xnflags_t info;
int err = 0;
spl_t s;
xnlock_get_irqsave(&nklock, s);
event = xeno_h2obj_validate(event, XENO_EVENT_MAGIC, RT_EVENT);
if (!event) {
err = xeno_handle_error(event, XENO_EVENT_MAGIC, RT_EVENT);
goto unlock_and_exit;
}
if (!mask) {
*mask_r = event->value;
goto unlock_and_exit;
}
if (timeout == TM_NONBLOCK) {
unsigned long bits = (event->value & mask);
*mask_r = bits;
if (mode & EV_ANY) {
if (!bits)
err = -EWOULDBLOCK;
} else if (bits != mask)
err = -EWOULDBLOCK;
goto unlock_and_exit;
}
if (((mode & EV_ANY) && (mask & event->value) != 0) ||
(!(mode & EV_ANY) && ((mask & event->value) == mask))) {
*mask_r = (event->value & mask);
goto unlock_and_exit;
}
if (xnpod_unblockable_p()) {
err = -EPERM;
goto unlock_and_exit;
}
task = xeno_current_task();
task->wait_args.event.mode = mode;
task->wait_args.event.mask = mask;
info = xnsynch_sleep_on(&event->synch_base,
timeout, timeout_mode);
if (info & XNRMID)
err = -EIDRM; /* Event group deleted while pending. */
else if (info & XNTIMEO)
err = -ETIMEDOUT; /* Timeout. */
else if (info & XNBREAK)
err = -EINTR; /* Unblocked. */
/*
* The returned mask is only significant if the operation has
* succeeded, but do always write it back anyway.
*/
*mask_r = task->wait_args.event.mask;
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
int rt_cond_wait_prologue(RT_COND *cond, RT_MUTEX *mutex, unsigned *plockcnt,
xntmode_t timeout_mode, RTIME timeout)
{
xnthread_t *thread;
xnflags_t info;
spl_t s;
int err;
if (timeout == TM_NONBLOCK)
return -EWOULDBLOCK;
if (xnpod_unblockable_p())
return -EPERM;
xnlock_get_irqsave(&nklock, s);
cond = xeno_h2obj_validate(cond, XENO_COND_MAGIC, RT_COND);
if (!cond) {
err = xeno_handle_error(cond, XENO_COND_MAGIC, RT_COND);
goto unlock_and_exit;
}
mutex = xeno_h2obj_validate(mutex, XENO_MUTEX_MAGIC, RT_MUTEX);
if (!mutex) {
err = xeno_handle_error(mutex, XENO_MUTEX_MAGIC, RT_MUTEX);
goto unlock_and_exit;
}
thread = xnpod_current_thread();
err = xnsynch_owner_check(&mutex->synch_base, thread);
if (err)
goto unlock_and_exit;
/*
* We can't use rt_mutex_release since that might reschedule
* before enter xnsynch_sleep_on.
*/
*plockcnt = mutex->lockcnt; /* Leave even if mutex is nested */
mutex->lockcnt = 0;
xnsynch_release(&mutex->synch_base);
/* Scheduling deferred */
info = xnsynch_sleep_on(&cond->synch_base,
timeout, timeout_mode);
if (info & XNRMID)
err = -EIDRM; /* Condvar deleted while pending. */
else if (info & XNTIMEO)
err = -ETIMEDOUT; /* Timeout. */
else if (info & XNBREAK) {
err = -EINTR; /* Unblocked. */
}
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return err;
}
ssize_t rt_buffer_read_inner(RT_BUFFER *bf,
struct xnbufd *bufd,
xntmode_t timeout_mode, RTIME timeout)
{
xnthread_t *thread, *waiter;
size_t len, rbytes, n;
xnflags_t info;
u_long rdtoken;
off_t rdoff;
ssize_t ret;
spl_t s;
xnlock_get_irqsave(&nklock, s);
bf = xeno_h2obj_validate(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
if (bf == NULL) {
ret = xeno_handle_error(bf, XENO_BUFFER_MAGIC, RT_BUFFER);
goto unlock_and_exit;
}
/*
* We may only return complete messages to readers, so there
* is no point in waiting for messages which are larger than
* what the buffer can hold.
*/
len = bufd->b_len;
if (len > bf->bufsz) {
ret = -EINVAL;
goto unlock_and_exit;
}
if (len == 0) {
ret = 0;
goto unlock_and_exit;
}
if (timeout_mode == XN_RELATIVE &&
timeout != TM_NONBLOCK && timeout != TM_INFINITE) {
/*
* We may sleep several times before receiving the
* data, so let's always use an absolute time spec.
*/
timeout_mode = XN_REALTIME;
timeout += xntbase_get_time(__native_tbase);
}
redo:
for (;;) {
/*
* We should be able to read a complete message of the
* requested length, or block.
*/
if (bf->fillsz < len)
goto wait;
/*
* Draw the next read token so that we can later
* detect preemption.
*/
rdtoken = ++bf->rdtoken;
/* Read from the buffer in a circular way. */
rdoff = bf->rdoff;
rbytes = len;
do {
if (rdoff + rbytes > bf->bufsz)
n = bf->bufsz - rdoff;
else
n = rbytes;
/*
* Release the nklock while retrieving the
* data to keep latency low.
*/
xnlock_put_irqrestore(&nklock, s);
ret = xnbufd_copy_from_kmem(bufd, bf->bufmem + rdoff, n);
if (ret < 0)
return ret;
xnlock_get_irqsave(&nklock, s);
/*
* In case we were preempted while retrieving
* the message, we have to re-read the whole
* thing.
*/
if (bf->rdtoken != rdtoken) {
xnbufd_reset(bufd);
goto redo;
}
rdoff = (rdoff + n) % bf->bufsz;
rbytes -= n;
} while (rbytes > 0);
bf->fillsz -= len;
bf->rdoff = rdoff;
ret = (ssize_t)len;
/*
* Wake up all threads pending on the output wait
* queue, if we freed enough room for the leading one
* to post its message.
*/
waiter = xnsynch_peek_pendq(&bf->osynch_base);
if (waiter && waiter->wait_u.size + bf->fillsz <= bf->bufsz) {
if (xnsynch_flush(&bf->osynch_base, 0) == XNSYNCH_RESCHED)
xnpod_schedule();
}
/*
* We cannot fail anymore once some data has been
* copied via the buffer descriptor, so no need to
* check for any reason to invalidate the latter.
*/
goto unlock_and_exit;
wait:
if (timeout_mode == XN_RELATIVE && timeout == TM_NONBLOCK) {
ret = -EWOULDBLOCK;
break;
}
if (xnpod_unblockable_p()) {
ret = -EPERM;
break;
}
/*
* Check whether writers are already waiting for
* sending data, while we are about to wait for
* receiving some. In such a case, we have a
* pathological use of the buffer. We must allow for a
* short read to prevent a deadlock.
*/
if (bf->fillsz > 0 &&
xnsynch_nsleepers(&bf->osynch_base) > 0) {
len = bf->fillsz;
goto redo;
}
thread = xnpod_current_thread();
thread->wait_u.bufd = bufd;
info = xnsynch_sleep_on(&bf->isynch_base,
timeout, timeout_mode);
if (info & XNRMID) {
ret = -EIDRM; /* Buffer deleted while pending. */
break;
} else if (info & XNTIMEO) {
ret = -ETIMEDOUT; /* Timeout. */
break;
} if (info & XNBREAK) {
ret = -EINTR; /* Unblocked. */
break;
}
}
unlock_and_exit:
xnlock_put_irqrestore(&nklock, s);
return ret;
}