hw/vfio/platform: add irq assignment

This patch adds the code requested to assign interrupts to
a guest. The interrupts are mediated through user handled
eventfds only.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/include/hw/vfio/vfio-platform.h b/include/hw/vfio/vfio-platform.h
index 338f0c6163..26b2ad6f4e 100644
--- a/include/hw/vfio/vfio-platform.h
+++ b/include/hw/vfio/vfio-platform.h
@@ -18,14 +18,45 @@
 
 #include "hw/sysbus.h"
 #include "hw/vfio/vfio-common.h"
+#include "qemu/event_notifier.h"
+#include "qemu/queue.h"
+#include "hw/irq.h"
 
 #define TYPE_VFIO_PLATFORM "vfio-platform"
 
+enum {
+    VFIO_IRQ_INACTIVE = 0,
+    VFIO_IRQ_PENDING = 1,
+    VFIO_IRQ_ACTIVE = 2,
+    /* VFIO_IRQ_ACTIVE_AND_PENDING cannot happen with VFIO */
+};
+
+typedef struct VFIOINTp {
+    QLIST_ENTRY(VFIOINTp) next; /* entry for IRQ list */
+    QSIMPLEQ_ENTRY(VFIOINTp) pqnext; /* entry for pending IRQ queue */
+    EventNotifier interrupt; /* eventfd triggered on interrupt */
+    EventNotifier unmask; /* eventfd for unmask on QEMU bypass */
+    qemu_irq qemuirq;
+    struct VFIOPlatformDevice *vdev; /* back pointer to device */
+    int state; /* inactive, pending, active */
+    uint8_t pin; /* index */
+    uint32_t flags; /* IRQ info flags */
+} VFIOINTp;
+
+/* function type for user side eventfd handler */
+typedef void (*eventfd_user_side_handler_t)(VFIOINTp *intp);
+
 typedef struct VFIOPlatformDevice {
     SysBusDevice sbdev;
     VFIODevice vbasedev; /* not a QOM object */
     VFIORegion **regions;
+    QLIST_HEAD(, VFIOINTp) intp_list; /* list of IRQs */
+    /* queue of pending IRQs */
+    QSIMPLEQ_HEAD(pending_intp_queue, VFIOINTp) pending_intp_queue;
     char *compat; /* compatibility string */
+    uint32_t mmap_timeout; /* delay to re-enable mmaps after interrupt */
+    QEMUTimer *mmap_timer; /* allows fast-path resume after IRQ hit */
+    QemuMutex intp_mutex; /* protect the intp_list IRQ state */
 } VFIOPlatformDevice;
 
 typedef struct VFIOPlatformDeviceClass {