virt: acrn: Introduce interfaces for virtual device creating/destroying

The ACRN hypervisor can emulate a virtual device within hypervisor for a
Guest VM. The emulated virtual device can work without the ACRN
userspace after creation. The hypervisor do the emulation of that device.

To support the virtual device creating/destroying, HSM provides the
following ioctls:
  - ACRN_IOCTL_CREATE_VDEV
    Pass data struct acrn_vdev from userspace to the hypervisor, and inform
    the hypervisor to create a virtual device for a User VM.
  - ACRN_IOCTL_DESTROY_VDEV
    Pass data struct acrn_vdev from userspace to the hypervisor, and inform
    the hypervisor to destroy a virtual device of a User VM.

These new APIs will be used by user space code vm_add_hv_vdev and
vm_remove_hv_vdev in
https://github.com/projectacrn/acrn-hypervisor/blob/master/devicemodel/core/vmmapi.c

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Signed-off-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20210923084128.18902-3-fei1.li@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 50 insertions, 0 deletions

diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index f567ca59d7c2..5419794fccf1 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -118,6 +118,7 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
 	struct acrn_msi_entry *msi;
 	struct acrn_pcidev *pcidev;
 	struct acrn_irqfd irqfd;
+	struct acrn_vdev *vdev;
 	struct page *page;
 	u64 cstate_cmd;
 	int i, ret = 0;
@@ -266,6 +267,29 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
 				"Failed to deassign pci device!\n");
 		kfree(pcidev);
 		break;
+	case ACRN_IOCTL_CREATE_VDEV:
+		vdev = memdup_user((void __user *)ioctl_param,
+				   sizeof(struct acrn_vdev));
+		if (IS_ERR(vdev))
+			return PTR_ERR(vdev);
+
+		ret = hcall_create_vdev(vm->vmid, virt_to_phys(vdev));
+		if (ret < 0)
+			dev_dbg(acrn_dev.this_device,
+				"Failed to create virtual device!\n");
+		kfree(vdev);
+		break;
+	case ACRN_IOCTL_DESTROY_VDEV:
+		vdev = memdup_user((void __user *)ioctl_param,
+				   sizeof(struct acrn_vdev));
+		if (IS_ERR(vdev))
+			return PTR_ERR(vdev);
+		ret = hcall_destroy_vdev(vm->vmid, virt_to_phys(vdev));
+		if (ret < 0)
+			dev_dbg(acrn_dev.this_device,
+				"Failed to destroy virtual device!\n");
+		kfree(vdev);
+		break;
 	case ACRN_IOCTL_SET_PTDEV_INTR:
 		irq_info = memdup_user((void __user *)ioctl_param,
 				       sizeof(struct acrn_ptdev_irq));
diff --git a/drivers/virt/acrn/hypercall.h b/drivers/virt/acrn/hypercall.h
index f0c78e52cebb..71d300821a18 100644
--- a/drivers/virt/acrn/hypercall.h
+++ b/drivers/virt/acrn/hypercall.h
@@ -43,6 +43,8 @@
 #define HC_DEASSIGN_PCIDEV		_HC_ID(HC_ID, HC_ID_PCI_BASE + 0x06)
 #define HC_ASSIGN_MMIODEV		_HC_ID(HC_ID, HC_ID_PCI_BASE + 0x07)
 #define HC_DEASSIGN_MMIODEV		_HC_ID(HC_ID, HC_ID_PCI_BASE + 0x08)
+#define HC_CREATE_VDEV			_HC_ID(HC_ID, HC_ID_PCI_BASE + 0x09)
+#define HC_DESTROY_VDEV			_HC_ID(HC_ID, HC_ID_PCI_BASE + 0x0A)
 
 #define HC_ID_PM_BASE			0x80UL
 #define HC_PM_GET_CPU_STATE		_HC_ID(HC_ID, HC_ID_PM_BASE + 0x00)
@@ -197,6 +199,30 @@ static inline long hcall_set_memory_regions(u64 regions_pa)
 }
 
 /**
+ * hcall_create_vdev() - Create a virtual device for a User VM
+ * @vmid:	User VM ID
+ * @addr:	Service VM GPA of the &struct acrn_vdev
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_create_vdev(u64 vmid, u64 addr)
+{
+	return acrn_hypercall2(HC_CREATE_VDEV, vmid, addr);
+}
+
+/**
+ * hcall_destroy_vdev() - Destroy a virtual device of a User VM
+ * @vmid:	User VM ID
+ * @addr:	Service VM GPA of the &struct acrn_vdev
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_destroy_vdev(u64 vmid, u64 addr)
+{
+	return acrn_hypercall2(HC_DESTROY_VDEV, vmid, addr);
+}
+
+/**
  * hcall_assign_mmiodev() - Assign a MMIO device to a User VM
  * @vmid:	User VM ID
  * @addr:	Service VM GPA of the &struct acrn_mmiodev