[PATCH v3 10/12] vfio-user: handle device interrupts

[Jagannathan Raman <jag.raman@oracle.com>]

Forward remote device's interrupts to the guest

Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 include/hw/remote/iohub.h |  2 ++
 hw/remote/iohub.c         |  5 +++++
 hw/remote/vfio-user-obj.c | 28 ++++++++++++++++++++++++++++
 hw/remote/trace-events    |  1 +
 4 files changed, 36 insertions(+)

diff --git a/include/hw/remote/iohub.h b/include/hw/remote/iohub.h
index 0bf98e0d78..d5bd0b08b0 100644
--- a/include/hw/remote/iohub.h
+++ b/include/hw/remote/iohub.h
@@ -15,6 +15,7 @@
 #include "qemu/event_notifier.h"
 #include "qemu/thread-posix.h"
 #include "hw/remote/mpqemu-link.h"
+#include "libvfio-user.h"
 
 #define REMOTE_IOHUB_NB_PIRQS    PCI_DEVFN_MAX
 
@@ -30,6 +31,7 @@ typedef struct RemoteIOHubState {
     unsigned int irq_level[REMOTE_IOHUB_NB_PIRQS];
     ResampleToken token[REMOTE_IOHUB_NB_PIRQS];
     QemuMutex irq_level_lock[REMOTE_IOHUB_NB_PIRQS];
+    vfu_ctx_t *vfu_ctx[REMOTE_IOHUB_NB_PIRQS];
 } RemoteIOHubState;
 
 int remote_iohub_map_irq(PCIDevice *pci_dev, int intx);
diff --git a/hw/remote/iohub.c b/hw/remote/iohub.c
index 547d597f0f..94102338a8 100644
--- a/hw/remote/iohub.c
+++ b/hw/remote/iohub.c
@@ -18,6 +18,7 @@
 #include "hw/remote/machine.h"
 #include "hw/remote/iohub.h"
 #include "qemu/main-loop.h"
+#include "trace.h"
 
 void remote_iohub_init(RemoteIOHubState *iohub)
 {
@@ -62,6 +63,10 @@ void remote_iohub_set_irq(void *opaque, int pirq, int level)
     QEMU_LOCK_GUARD(&iohub->irq_level_lock[pirq]);
 
     if (level) {
+        if (iohub->vfu_ctx[pirq]) {
+            trace_vfu_interrupt(pirq);
+            vfu_irq_trigger(iohub->vfu_ctx[pirq], 0);
+        }
         if (++iohub->irq_level[pirq] == 1) {
             event_notifier_set(&iohub->irqfds[pirq]);
         }
diff --git a/hw/remote/vfio-user-obj.c b/hw/remote/vfio-user-obj.c
index 4c9ed1543c..63c468d6f3 100644
--- a/hw/remote/vfio-user-obj.c
+++ b/hw/remote/vfio-user-obj.c
@@ -48,6 +48,7 @@
 #include "libvfio-user.h"
 #include "hw/qdev-core.h"
 #include "hw/pci/pci.h"
+#include "hw/remote/iohub.h"
 
 #define TYPE_VFU_OBJECT "vfio-user-server"
 OBJECT_DECLARE_TYPE(VfuObject, VfuObjectClass, VFU_OBJECT)
@@ -325,6 +326,26 @@ static void vfu_object_register_bars(vfu_ctx_t *vfu_ctx, PCIDevice *pdev)
     }
 }
 
+static int vfu_object_setup_irqs(vfu_ctx_t *vfu_ctx, PCIDevice *pci_dev)
+{
+    RemoteMachineState *machine = REMOTE_MACHINE(current_machine);
+    RemoteIOHubState *iohub = &machine->iohub;
+    int pirq, intx, ret;
+
+    ret = vfu_setup_device_nr_irqs(vfu_ctx, VFU_DEV_INTX_IRQ, 1);
+    if (ret < 0) {
+        return ret;
+    }
+
+    intx = pci_get_byte(pci_dev->config + PCI_INTERRUPT_PIN) - 1;
+
+    pirq = remote_iohub_map_irq(pci_dev, intx);
+
+    iohub->vfu_ctx[pirq] = vfu_ctx;
+
+    return 0;
+}
+
 /*
  * vfio-user-server depends on the availability of the 'socket' and 'device'
  * properties. It also depends on devices instantiated in QEMU. These
@@ -394,6 +415,13 @@ static void vfu_object_machine_done(Notifier *notifier, void *data)
 
     vfu_object_register_bars(o->vfu_ctx, o->pci_dev);
 
+    ret = vfu_object_setup_irqs(o->vfu_ctx, o->pci_dev);
+    if (ret < 0) {
+        error_setg(&error_abort, "vfu: Failed to setup interrupts for %s",
+                   o->device);
+        return;
+    }
+
     ret = vfu_realize_ctx(o->vfu_ctx);
     if (ret < 0) {
         error_setg(&error_abort, "vfu: Failed to realize device %s- %s",
diff --git a/hw/remote/trace-events b/hw/remote/trace-events
index 847d50d88f..c167b3c7a5 100644
--- a/hw/remote/trace-events
+++ b/hw/remote/trace-events
@@ -12,3 +12,4 @@ vfu_dma_unregister(uint64_t gpa) "vfu: unregistering GPA 0x%"PRIx64""
 vfu_bar_register(int i, uint64_t addr, uint64_t size) "vfu: BAR %d: addr 0x%"PRIx64" size 0x%"PRIx64""
 vfu_bar_rw_enter(const char *op, uint64_t addr) "vfu: %s request for BAR address 0x%"PRIx64""
 vfu_bar_rw_exit(const char *op, uint64_t addr) "vfu: Finished %s of BAR address 0x%"PRIx64""
+vfu_interrupt(int pirq) "vfu: sending interrupt to device - PIRQ %d"
-- 
2.20.1