irqchip/armada-370-xp: Fix support for Multi-MSI interrupts

commit d0a553502efd545c1ce3fd08fc4d423f8e4ac3d6 upstream.

irq-armada-370-xp driver already sets MSI_FLAG_MULTI_PCI_MSI flag into
msi_domain_info structure. But allocated interrupt numbers for Multi-MSI
needs to be properly aligned otherwise devices send MSI interrupt with
wrong number.

Fix this issue by using function bitmap_find_free_region() instead of
bitmap_find_next_zero_area() to allocate aligned interrupt numbers.

Signed-off-by: Pali Rohár <pali@kernel.org>
Fixes: a71b9412c90c ("irqchip/armada-370-xp: Allow allocation of multiple MSIs")
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211125130057.26705-2-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
index 2b82ebb..c91ddb0 100644 (file)
--- a/drivers/irqchip/irq-armada-370-xp.c
+++ b/drivers/irqchip/irq-armada-370-xp.c
@@ -232,16 +232,12 @@ static int armada_370_xp_msi_alloc(struct irq_domain *domain, unsigned int virq,
        int hwirq, i;
 
        mutex_lock(&msi_used_lock);
+       hwirq = bitmap_find_free_region(msi_used, PCI_MSI_DOORBELL_NR,
+                                       order_base_2(nr_irqs));
+       mutex_unlock(&msi_used_lock);
 
-       hwirq = bitmap_find_next_zero_area(msi_used, PCI_MSI_DOORBELL_NR,
-                                          0, nr_irqs, 0);
-       if (hwirq >= PCI_MSI_DOORBELL_NR) {
-               mutex_unlock(&msi_used_lock);
+       if (hwirq < 0)
                return -ENOSPC;
-       }
-
-       bitmap_set(msi_used, hwirq, nr_irqs);
-       mutex_unlock(&msi_used_lock);
 
        for (i = 0; i < nr_irqs; i++) {
                irq_domain_set_info(domain, virq + i, hwirq + i,
@@ -259,7 +255,7 @@ static void armada_370_xp_msi_free(struct irq_domain *domain,
        struct irq_data *d = irq_domain_get_irq_data(domain, virq);
 
        mutex_lock(&msi_used_lock);
-       bitmap_clear(msi_used, d->hwirq, nr_irqs);
+       bitmap_release_region(msi_used, d->hwirq, order_base_2(nr_irqs));
        mutex_unlock(&msi_used_lock);
 }