virt: acrn: Introduce VM management interfaces

The VM management interfaces expose several VM operations to ACRN
userspace via ioctls. For example, creating VM, starting VM, destroying
VM and so on.

The ACRN Hypervisor needs to exchange data with the ACRN userspace
during the VM operations. HSM provides VM operation ioctls to the ACRN
userspace and communicates with the ACRN Hypervisor for VM operations
via hypercalls.

HSM maintains a list of User VM. Each User VM will be bound to an
existing file descriptor of /dev/acrn_hsm. The User VM will be
destroyed when the file descriptor is closed.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-7-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 74 insertions, 2 deletions

diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index a8dcb250649d..5fd933471683 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -9,7 +9,6 @@
  *	Yakui Zhao <yakui.zhao@intel.com>
  */
 
-#include <linux/miscdevice.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/slab.h>
@@ -38,10 +37,82 @@ static int acrn_dev_open(struct inode *inode, struct file *filp)
 	return 0;
 }
 
+/*
+ * HSM relies on hypercall layer of the ACRN hypervisor to do the
+ * sanity check against the input parameters.
+ */
+static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
+			   unsigned long ioctl_param)
+{
+	struct acrn_vm *vm = filp->private_data;
+	struct acrn_vm_creation *vm_param;
+	int ret = 0;
+
+	if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) {
+		dev_dbg(acrn_dev.this_device,
+			"ioctl 0x%x: Invalid VM state!\n", cmd);
+		return -EINVAL;
+	}
+
+	switch (cmd) {
+	case ACRN_IOCTL_CREATE_VM:
+		vm_param = memdup_user((void __user *)ioctl_param,
+				       sizeof(struct acrn_vm_creation));
+		if (IS_ERR(vm_param))
+			return PTR_ERR(vm_param);
+
+		if ((vm_param->reserved0 | vm_param->reserved1) != 0)
+			return -EINVAL;
+
+		vm = acrn_vm_create(vm, vm_param);
+		if (!vm) {
+			ret = -EINVAL;
+			kfree(vm_param);
+			break;
+		}
+
+		if (copy_to_user((void __user *)ioctl_param, vm_param,
+				 sizeof(struct acrn_vm_creation))) {
+			acrn_vm_destroy(vm);
+			ret = -EFAULT;
+		}
+
+		kfree(vm_param);
+		break;
+	case ACRN_IOCTL_START_VM:
+		ret = hcall_start_vm(vm->vmid);
+		if (ret < 0)
+			dev_dbg(acrn_dev.this_device,
+				"Failed to start VM %u!\n", vm->vmid);
+		break;
+	case ACRN_IOCTL_PAUSE_VM:
+		ret = hcall_pause_vm(vm->vmid);
+		if (ret < 0)
+			dev_dbg(acrn_dev.this_device,
+				"Failed to pause VM %u!\n", vm->vmid);
+		break;
+	case ACRN_IOCTL_RESET_VM:
+		ret = hcall_reset_vm(vm->vmid);
+		if (ret < 0)
+			dev_dbg(acrn_dev.this_device,
+				"Failed to restart VM %u!\n", vm->vmid);
+		break;
+	case ACRN_IOCTL_DESTROY_VM:
+		ret = acrn_vm_destroy(vm);
+		break;
+	default:
+		dev_dbg(acrn_dev.this_device, "Unknown IOCTL 0x%x!\n", cmd);
+		ret = -ENOTTY;
+	}
+
+	return ret;
+}
+
 static int acrn_dev_release(struct inode *inode, struct file *filp)
 {
 	struct acrn_vm *vm = filp->private_data;
 
+	acrn_vm_destroy(vm);
 	kfree(vm);
 	return 0;
 }
@@ -50,9 +121,10 @@ static const struct file_operations acrn_fops = {
 	.owner		= THIS_MODULE,
 	.open		= acrn_dev_open,
 	.release	= acrn_dev_release,
+	.unlocked_ioctl = acrn_dev_ioctl,
 };
 
-static struct miscdevice acrn_dev = {
+struct miscdevice acrn_dev = {
 	.minor	= MISC_DYNAMIC_MINOR,
 	.name	= "acrn_hsm",
 	.fops	= &acrn_fops,