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Ignore whitespace Rev 4347 → Rev 4348

/branches/dynload/kernel/generic/src/ipc/irq.c
128,13 → 128,14
 
/** Register an answerbox as a receiving end for IRQ notifications.
*
* @param box Receiving answerbox.
* @param inr IRQ number.
* @param devno Device number.
* @param method Method to be associated with the notification.
* @param ucode Uspace pointer to top-half pseudocode.
* @param box Receiving answerbox.
* @param inr IRQ number.
* @param devno Device number.
* @param method Method to be associated with the notification.
* @param ucode Uspace pointer to top-half pseudocode.
*
* @return EBADMEM, ENOENT or EEXISTS on failure or 0 on success.
* @return EBADMEM, ENOENT or EEXISTS on failure or 0 on success.
*
*/
int ipc_irq_register(answerbox_t *box, inr_t inr, devno_t devno,
unative_t method, irq_code_t *ucode)
142,11 → 143,12
ipl_t ipl;
irq_code_t *code;
irq_t *irq;
link_t *hlp;
unative_t key[] = {
(unative_t) inr,
(unative_t) devno
};
 
if (ucode) {
code = code_from_uspace(ucode);
if (!code)
154,7 → 156,7
} else {
code = NULL;
}
 
/*
* Allocate and populate the IRQ structure.
*/
169,7 → 171,7
irq->notif_cfg.method = method;
irq->notif_cfg.code = code;
irq->notif_cfg.counter = 0;
 
/*
* Enlist the IRQ structure in the uspace IRQ hash table and the
* answerbox's list.
176,23 → 178,28
*/
ipl = interrupts_disable();
spinlock_lock(&irq_uspace_hash_table_lock);
spinlock_lock(&irq->lock);
spinlock_lock(&box->irq_lock);
if (hash_table_find(&irq_uspace_hash_table, key)) {
hlp = hash_table_find(&irq_uspace_hash_table, key);
if (hlp) {
irq_t *hirq __attribute__((unused))
= hash_table_get_instance(hlp, irq_t, link);
/* hirq is locked */
spinlock_unlock(&hirq->lock);
code_free(code);
spinlock_unlock(&box->irq_lock);
spinlock_unlock(&irq->lock);
spinlock_unlock(&irq_uspace_hash_table_lock);
free(irq);
interrupts_restore(ipl);
return EEXISTS;
}
spinlock_lock(&irq->lock); /* Not really necessary, but paranoid */
spinlock_lock(&box->irq_lock);
hash_table_insert(&irq_uspace_hash_table, key, &irq->link);
list_append(&irq->notif_cfg.link, &box->irq_head);
spinlock_unlock(&box->irq_lock);
spinlock_unlock(&irq->lock);
spinlock_unlock(&irq_uspace_hash_table_lock);
 
interrupts_restore(ipl);
return EOK;
}
222,7 → 229,7
return ENOENT;
}
irq = hash_table_get_instance(lnk, irq_t, link);
spinlock_lock(&irq->lock);
/* irq is locked */
spinlock_lock(&box->irq_lock);
ASSERT(irq->notif_cfg.answerbox == box);
233,11 → 240,19
/* Remove the IRQ from the answerbox's list. */
list_remove(&irq->notif_cfg.link);
 
/*
* We need to drop the IRQ lock now because hash_table_remove() will try
* to reacquire it. That basically violates the natural locking order,
* but a deadlock in hash_table_remove() is prevented by the fact that
* we already held the IRQ lock and didn't drop the hash table lock in
* the meantime.
*/
spinlock_unlock(&irq->lock);
 
/* Remove the IRQ from the uspace IRQ hash table. */
hash_table_remove(&irq_uspace_hash_table, key, 2);
spinlock_unlock(&irq_uspace_hash_table_lock);
spinlock_unlock(&irq->lock);
spinlock_unlock(&box->irq_lock);
/* Free up the IRQ structure. */
291,13 → 306,21
/* Unlist from the answerbox. */
list_remove(&irq->notif_cfg.link);
/* Remove from the hash table. */
hash_table_remove(&irq_uspace_hash_table, key, 2);
/* Free up the pseudo code and associated structures. */
code_free(irq->notif_cfg.code);
/*
* We need to drop the IRQ lock now because hash_table_remove()
* will try to reacquire it. That basically violates the natural
* locking order, but a deadlock in hash_table_remove() is
* prevented by the fact that we already held the IRQ lock and
* didn't drop the hash table lock in the meantime.
*/
spinlock_unlock(&irq->lock);
/* Remove from the hash table. */
hash_table_remove(&irq_uspace_hash_table, key, 2);
free(irq);
}