[RFC PATCH V2 06/18] vfio/pci: Separate MSI and MSI-X handling

[Reinette Chatre]

VFIO PCI interrupt management uses a single entry for both
MSI and MSI-X management with the called functions using a boolean
when necessary to distinguish between MSI and MSI-X. This remains
unchanged.

Virtual device interrupt management should not be required to
use the same callback for both MSI and MSI-X. It may be possible
for a virtual device to not support MSI at all and only
provide MSI-X interrupt management.

Separate the MSI and MSI-X interrupt management by allowing
different callbacks for each interrupt type. For PCI devices
the callback remains the same.

Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
 drivers/vfio/pci/vfio_pci_intrs.c | 14 +++++++++++++-
 include/linux/vfio_pci_core.h     |  3 +++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
index e2d39b7561b8..76ec5af3681a 100644
--- a/drivers/vfio/pci/vfio_pci_intrs.c
+++ b/drivers/vfio/pci/vfio_pci_intrs.c
@@ -800,6 +800,7 @@ struct vfio_pci_intr_ops vfio_pci_intr_ops = {
 	.set_intx_unmask = vfio_pci_set_intx_unmask,
 	.set_intx_trigger = vfio_pci_set_intx_trigger,
 	.set_msi_trigger = vfio_pci_set_msi_trigger,
+	.set_msix_trigger = vfio_pci_set_msi_trigger,
 	.set_err_trigger = vfio_pci_set_err_trigger,
 	.set_req_trigger = vfio_pci_set_req_trigger,
 };
@@ -838,7 +839,6 @@ int vfio_pci_set_irqs_ioctl(struct vfio_pci_intr_ctx *intr_ctx, uint32_t flags,
 		}
 		break;
 	case VFIO_PCI_MSI_IRQ_INDEX:
-	case VFIO_PCI_MSIX_IRQ_INDEX:
 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 		case VFIO_IRQ_SET_ACTION_MASK:
 		case VFIO_IRQ_SET_ACTION_UNMASK:
@@ -850,6 +850,18 @@ int vfio_pci_set_irqs_ioctl(struct vfio_pci_intr_ctx *intr_ctx, uint32_t flags,
 			break;
 		}
 		break;
+	case VFIO_PCI_MSIX_IRQ_INDEX:
+		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+		case VFIO_IRQ_SET_ACTION_MASK:
+		case VFIO_IRQ_SET_ACTION_UNMASK:
+			/* XXX Need masking support exported */
+			break;
+		case VFIO_IRQ_SET_ACTION_TRIGGER:
+			if (intr_ctx->ops->set_msix_trigger)
+				func = intr_ctx->ops->set_msix_trigger;
+			break;
+		}
+		break;
 	case VFIO_PCI_ERR_IRQ_INDEX:
 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
 		case VFIO_IRQ_SET_ACTION_TRIGGER:
diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h
index aba69669ec25..e9bfca9a0c0a 100644
--- a/include/linux/vfio_pci_core.h
+++ b/include/linux/vfio_pci_core.h
@@ -72,6 +72,9 @@ struct vfio_pci_intr_ops {
 	int (*set_msi_trigger)(struct vfio_pci_intr_ctx *intr_ctx,
 			       unsigned int index, unsigned int start,
 			       unsigned int count, uint32_t flags, void *data);
+	int (*set_msix_trigger)(struct vfio_pci_intr_ctx *intr_ctx,
+				unsigned int index, unsigned int start,
+				unsigned int count, uint32_t flags, void *data);
 	int (*set_err_trigger)(struct vfio_pci_intr_ctx *intr_ctx,
 			       unsigned int index, unsigned int start,
 			       unsigned int count, uint32_t flags, void *data);
-- 
2.34.1