[PATCH v4 05/17] virt: acrn: Introduce ACRN HSM basic driver

shuo.a.liu
2020-09-22T11:47:13Z

From: Shuo Liu <shuo.a.liu@intel.com>

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.

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
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>
---
MAINTAINERS | 1 +
drivers/virt/Kconfig | 2 +
drivers/virt/Makefile | 1 +
drivers/virt/acrn/Kconfig | 14 ++++++
drivers/virt/acrn/Makefile | 3 ++
drivers/virt/acrn/acrn_drv.h | 18 ++++++++
drivers/virt/acrn/hsm.c | 87 ++++++++++++++++++++++++++++++++++++
7 files changed, 126 insertions(+)
create mode 100644 drivers/virt/acrn/Kconfig
create mode 100644 drivers/virt/acrn/Makefile
create mode 100644 drivers/virt/acrn/acrn_drv.h
create mode 100644 drivers/virt/acrn/hsm.c

diff --git a/MAINTAINERS b/MAINTAINERS
index e0fea5e464b4..3030d0e93d02 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -442,6 +442,7 @@ L: acrn-dev@lists.projectacrn.org
S: Supported
W: https://projectacrn.org
F: Documentation/virt/acrn/
+F: drivers/virt/acrn/

AD1889 ALSA SOUND DRIVER
L: linux-parisc@vger.kernel.org
diff --git a/drivers/virt/Kconfig b/drivers/virt/Kconfig
index cbc1f25c79ab..d9484a2e9b46 100644
--- a/drivers/virt/Kconfig
+++ b/drivers/virt/Kconfig
@@ -32,4 +32,6 @@ config FSL_HV_MANAGER
partition shuts down.

source "drivers/virt/vboxguest/Kconfig"
+
+source "drivers/virt/acrn/Kconfig"
endif
diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile
index fd331247c27a..f0491bbf0d4d 100644
--- a/drivers/virt/Makefile
+++ b/drivers/virt/Makefile
@@ -5,3 +5,4 @@

obj-$(CONFIG_FSL_HV_MANAGER) += fsl_hypervisor.o
obj-y += vboxguest/
+obj-$(CONFIG_ACRN_HSM) += acrn/
diff --git a/drivers/virt/acrn/Kconfig b/drivers/virt/acrn/Kconfig
new file mode 100644
index 000000000000..36c80378c30c
--- /dev/null
+++ b/drivers/virt/acrn/Kconfig
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0
+config ACRN_HSM
+ tristate "ACRN Hypervisor Service Module"
+ depends on ACRN_GUEST
+ help
+ ACRN Hypervisor Service Module (HSM) is a kernel module which
+ communicates with ACRN userspace through ioctls and talks to
+ the ACRN Hypervisor through hypercalls. HSM will only run in
+ a privileged management VM, called Service VM, to manage User
+ VMs and do I/O emulation. Not required for simply running
+ under ACRN as a User VM.
+
+ To compile as a module, choose M, the module will be called
+ acrn. If unsure, say N.
diff --git a/drivers/virt/acrn/Makefile b/drivers/virt/acrn/Makefile
new file mode 100644
index 000000000000..6920ed798aaf
--- /dev/null
+++ b/drivers/virt/acrn/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_ACRN_HSM) := acrn.o
+acrn-y := hsm.o
diff --git a/drivers/virt/acrn/acrn_drv.h b/drivers/virt/acrn/acrn_drv.h
new file mode 100644
index 000000000000..29eedd696327
--- /dev/null
+++ b/drivers/virt/acrn/acrn_drv.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ACRN_HSM_DRV_H
+#define __ACRN_HSM_DRV_H
+
+#include <linux/types.h>
+
+#define ACRN_INVALID_VMID (0xffffU)
+
+/**
+ * struct acrn_vm - Properties of ACRN User VM.
+ * @vmid: User VM ID
+ */
+struct acrn_vm {
+ u16 vmid;
+};
+
+#endif /* __ACRN_HSM_DRV_H */
diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
new file mode 100644
index 000000000000..28a3052ffa55
--- /dev/null
+++ b/drivers/virt/acrn/hsm.c
@@ -0,0 +1,87 @@
+// 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 (!acrn_is_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)");
--
2.28.0