linux/drivers/virt/acrn/hsm.c
Shuo Liu 666834c47d virt: acrn: Introduce ACRN HSM basic driver
ACRN Hypervisor Service Module (HSM) is a kernel module in Service VM
which communicates with ACRN userspace through ioctls and talks to ACRN
Hypervisor through hypercalls.

Add a basic HSM driver which allows Service VM userspace to communicate
with ACRN. The following patches will add more ioctls, guest VM memory
mapping caching, I/O request processing, ioeventfd and irqfd into this
module. HSM exports a char device interface (/dev/acrn_hsm) to userspace.

Cc: Dave Hansen <dave.hansen@intel.com>
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: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-6-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09 10:58:18 +01:00

88 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* ACRN Hypervisor Service Module (HSM)
*
* Copyright (C) 2020 Intel Corporation. All rights reserved.
*
* Authors:
* Fengwei Yin <fengwei.yin@intel.com>
* Yakui Zhao <yakui.zhao@intel.com>
*/
#include <linux/miscdevice.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <asm/acrn.h>
#include <asm/hypervisor.h>
#include "acrn_drv.h"
/*
* When /dev/acrn_hsm is opened, a 'struct acrn_vm' object is created to
* represent a VM instance and continues to be associated with the opened file
* descriptor. All ioctl operations on this file descriptor will be targeted to
* the VM instance. Release of this file descriptor will destroy the object.
*/
static int acrn_dev_open(struct inode *inode, struct file *filp)
{
struct acrn_vm *vm;
vm = kzalloc(sizeof(*vm), GFP_KERNEL);
if (!vm)
return -ENOMEM;
vm->vmid = ACRN_INVALID_VMID;
filp->private_data = vm;
return 0;
}
static int acrn_dev_release(struct inode *inode, struct file *filp)
{
struct acrn_vm *vm = filp->private_data;
kfree(vm);
return 0;
}
static const struct file_operations acrn_fops = {
.owner = THIS_MODULE,
.open = acrn_dev_open,
.release = acrn_dev_release,
};
static struct miscdevice acrn_dev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "acrn_hsm",
.fops = &acrn_fops,
};
static int __init hsm_init(void)
{
int ret;
if (x86_hyper_type != X86_HYPER_ACRN)
return -ENODEV;
if (!(cpuid_eax(ACRN_CPUID_FEATURES) & ACRN_FEATURE_PRIVILEGED_VM))
return -EPERM;
ret = misc_register(&acrn_dev);
if (ret)
pr_err("Create misc dev failed!\n");
return ret;
}
static void __exit hsm_exit(void)
{
misc_deregister(&acrn_dev);
}
module_init(hsm_init);
module_exit(hsm_exit);
MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ACRN Hypervisor Service Module (HSM)");