return spi_mask & (1 << (spi & 31));
}
-static int irqchip_init_pending(struct per_cpu *cpu_data)
+void irqchip_set_pending(struct per_cpu *cpu_data, u16 irq_id, bool try_inject)
{
- struct pending_irq *pend_array;
-
- if (cpu_data->pending_irqs == NULL) {
- cpu_data->pending_irqs = pend_array = page_alloc(&mem_pool, 1);
- if (pend_array == NULL)
- return -ENOMEM;
- } else {
- pend_array = cpu_data->pending_irqs;
- }
-
- memset(pend_array, 0, PAGE_SIZE);
-
- cpu_data->pending_irqs = pend_array;
- cpu_data->first_pending = NULL;
-
- return 0;
-}
-
-/*
- * Find the first available pending struct for insertion. The `prev' pointer is
- * set to the previous pending interrupt, if any, to help inserting the new one
- * into the list.
- * Returns NULL when no slot is available
- */
-static struct pending_irq* get_pending_slot(struct per_cpu *cpu_data,
- struct pending_irq **prev)
-{
- u32 i, pending_idx;
- struct pending_irq *pending = cpu_data->first_pending;
-
- *prev = NULL;
-
- for (i = 0; i < MAX_PENDING_IRQS; i++) {
- pending_idx = pending - cpu_data->pending_irqs;
- if (pending == NULL || i < pending_idx)
- return cpu_data->pending_irqs + i;
+ unsigned int new_tail;
- *prev = pending;
- pending = pending->next;
- }
-
- return NULL;
-}
+ if (try_inject && irqchip.inject_irq(cpu_data, irq_id) != -EBUSY)
+ return;
-int irqchip_insert_pending(struct per_cpu *cpu_data, struct pending_irq *irq)
-{
- struct pending_irq *prev = NULL;
- struct pending_irq *slot;
+ spin_lock(&cpu_data->pending_irqs_lock);
- spin_lock(&cpu_data->gic_lock);
+ new_tail = (cpu_data->pending_irqs_tail + 1) % MAX_PENDING_IRQS;
- slot = get_pending_slot(cpu_data, &prev);
- if (slot == NULL) {
- spin_unlock(&cpu_data->gic_lock);
- return -ENOMEM;
+ /* Queue space available? */
+ if (new_tail != cpu_data->pending_irqs_head) {
+ cpu_data->pending_irqs[cpu_data->pending_irqs_tail] = irq_id;
+ cpu_data->pending_irqs_tail = new_tail;
+ /*
+ * Make the change to pending_irqs_tail visible before the
+ * caller sends SGI_INJECT.
+ */
+ memory_barrier();
}
- /*
- * Don't override the pointers yet, they may be read by the injection
- * loop. Odds are astronomically low, but hey.
- */
- memcpy(slot, irq, sizeof(struct pending_irq) - 2 * sizeof(void *));
- slot->prev = prev;
- if (prev) {
- slot->next = prev->next;
- prev->next = slot;
- } else {
- slot->next = cpu_data->first_pending;
- cpu_data->first_pending = slot;
- }
- if (slot->next)
- slot->next->prev = slot;
-
- spin_unlock(&cpu_data->gic_lock);
-
- return 0;
-}
-
-void irqchip_set_pending(struct per_cpu *cpu_data, u32 irq_id, bool try_inject)
-{
- struct pending_irq pending;
-
- pending.virt_id = irq_id;
-
- if (!try_inject || irqchip.inject_irq(cpu_data, &pending) == -EBUSY)
- irqchip_insert_pending(cpu_data, &pending);
-}
-
-/*
- * Only executed by `irqchip_inject_pending' on a CPU to inject its own stuff.
- */
-int irqchip_remove_pending(struct per_cpu *cpu_data, struct pending_irq *irq)
-{
- spin_lock(&cpu_data->gic_lock);
-
- if (cpu_data->first_pending == irq)
- cpu_data->first_pending = irq->next;
- if (irq->prev)
- irq->prev->next = irq->next;
- if (irq->next)
- irq->next->prev = irq->prev;
-
- spin_unlock(&cpu_data->gic_lock);
-
- return 0;
+ spin_unlock(&cpu_data->pending_irqs_lock);
}
void irqchip_inject_pending(struct per_cpu *cpu_data)
{
- int err;
- struct pending_irq *pending = cpu_data->first_pending;
+ u16 irq_id;
- while (pending != NULL) {
- err = irqchip.inject_irq(cpu_data, pending);
- if (err == -EBUSY) {
+ while (cpu_data->pending_irqs_head != cpu_data->pending_irqs_tail) {
+ irq_id = cpu_data->pending_irqs[cpu_data->pending_irqs_head];
+
+ if (irqchip.inject_irq(cpu_data, irq_id) == -EBUSY) {
/*
* The list registers are full, trigger maintenance
* interrupt and leave.
*/
irqchip.enable_maint_irq(true);
return;
- } else {
- /*
- * Removal only changes the pointers, but does not
- * deallocate anything.
- * Concurrent accesses are avoided with the spinlock,
- * but the `next' pointer of the current pending object
- * may be rewritten by an external insert before or
- * after this removal, which isn't an issue.
- */
- irqchip_remove_pending(cpu_data, pending);
}
- pending = pending->next;
+ cpu_data->pending_irqs_head =
+ (cpu_data->pending_irqs_head + 1) % MAX_PENDING_IRQS;
}
/*
int irqchip_cpu_init(struct per_cpu *cpu_data)
{
- int err;
-
- err = irqchip_init_pending(cpu_data);
- if (err)
- return err;
-
if (irqchip.cpu_init)
return irqchip.cpu_init(cpu_data);
int irqchip_cpu_reset(struct per_cpu *cpu_data)
{
- int err;
-
- err = irqchip_init_pending(cpu_data);
- if (err)
- return err;
+ cpu_data->pending_irqs_head = cpu_data->pending_irqs_tail = 0;
if (irqchip.cpu_reset)
return irqchip.cpu_reset(cpu_data, false);
projects / jailhouse.git / blobdiff