4 files changed, 38 insertions, 1 deletions

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 7cc0122a18ce..f8a186381ae8 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -239,9 +239,12 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
 
                         return (flags & PCI_MSIX_FLAGS_QSIZE) + 1;
                 }
-        } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX)
+        } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) {
                 if (pci_is_pcie(vdev->pdev))
                         return 1;
+        } else if (irq_type == VFIO_PCI_REQ_IRQ_INDEX) {
+                return 1;
+        }
 
         return 0;
 }
@@ -464,6 +467,7 @@ static long vfio_pci_ioctl(void *device_data,
 
                 switch (info.index) {
                 case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX:
+                case VFIO_PCI_REQ_IRQ_INDEX:
                         break;
                 case VFIO_PCI_ERR_IRQ_INDEX:
                         if (pci_is_pcie(vdev->pdev))
@@ -828,6 +832,20 @@ static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma)
                                req_len, vma->vm_page_prot);
 }
 
+static void vfio_pci_request(void *device_data, unsigned int count)
+{
+        struct vfio_pci_device *vdev = device_data;
+
+        mutex_lock(&vdev->igate);
+
+        if (vdev->req_trigger) {
+                dev_dbg(&vdev->pdev->dev, "Requesting device from user\n");
+                eventfd_signal(vdev->req_trigger, 1);
+        }
+
+        mutex_unlock(&vdev->igate);
+}
+
 static const struct vfio_device_ops vfio_pci_ops = {
         .name           = "vfio-pci",
         .open           = vfio_pci_open,
@@ -836,6 +854,7 @@ static const struct vfio_device_ops vfio_pci_ops = {
         .read           = vfio_pci_read,
         .write          = vfio_pci_write,
         .mmap           = vfio_pci_mmap,
+        .request        = vfio_pci_request,
 };
 
 static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
index b134befbfd0e..f88bfdf5b6a0 100644
--- a/drivers/vfio/pci/vfio_pci_intrs.c
+++ b/drivers/vfio/pci/vfio_pci_intrs.c
@@ -817,6 +817,16 @@ static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev,
         return vfio_pci_set_ctx_trigger_single(&vdev->err_trigger, flags, data);
 }
 
+static int vfio_pci_set_req_trigger(struct vfio_pci_device *vdev,
+                                    unsigned index, unsigned start,
+                                    unsigned count, uint32_t flags, void *data)
+{
+        if (index != VFIO_PCI_REQ_IRQ_INDEX || start != 0 || count != 1)
+                return -EINVAL;
+
+        return vfio_pci_set_ctx_trigger_single(&vdev->req_trigger, flags, data);
+}
+
 int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
                             unsigned index, unsigned start, unsigned count,
                             void *data)
@@ -858,6 +868,12 @@ int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
                                 func = vfio_pci_set_err_trigger;
                         break;
                 }
+        case VFIO_PCI_REQ_IRQ_INDEX:
+                switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+                case VFIO_IRQ_SET_ACTION_TRIGGER:
+                        func = vfio_pci_set_req_trigger;
+                        break;
+                }
         }
 
         if (!func)
diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
index 671c17a6e6d0..c9f9b323f152 100644
--- a/drivers/vfio/pci/vfio_pci_private.h
+++ b/drivers/vfio/pci/vfio_pci_private.h
@@ -58,6 +58,7 @@ struct vfio_pci_device {
         struct pci_saved_state  *pci_saved_state;
         int                     refcnt;
         struct eventfd_ctx      *err_trigger;
+        struct eventfd_ctx      *req_trigger;
 };
 
 #define is_intx(vdev) (vdev->irq_type == VFIO_PCI_INTX_IRQ_INDEX)
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 29715d27548f..82889c30f4f5 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -333,6 +333,7 @@ enum {
         VFIO_PCI_MSI_IRQ_INDEX,
         VFIO_PCI_MSIX_IRQ_INDEX,
         VFIO_PCI_ERR_IRQ_INDEX,
+        VFIO_PCI_REQ_IRQ_INDEX,
         VFIO_PCI_NUM_IRQS
 };