[PATCH v8 04/20] virt: geniezone: Add vm support

[Yi-De Wu <yi-de.wu@mediatek.com>]

From: "Yingshiuan Pan" <yingshiuan.pan@mediatek.com>

The VM component is responsible for setting up the capability and memory
management for the protected VMs. The capability is mainly about the
lifecycle control and boot context initialization.

Signed-off-by: Yingshiuan Pan <yingshiuan.pan@mediatek.com>
Signed-off-by: Jerry Wang <ze-yu.wang@mediatek.com>
Signed-off-by: Liju Chen <liju-clr.chen@mediatek.com>
Signed-off-by: Yi-De Wu <yi-de.wu@mediatek.com>
---
 MAINTAINERS                             |   1 +
 arch/arm64/geniezone/gzvm_arch_common.h |   9 ++
 arch/arm64/geniezone/vm.c               |  29 +++++++
 drivers/virt/geniezone/Makefile         |   2 +-
 drivers/virt/geniezone/gzvm_main.c      |  19 +++++
 drivers/virt/geniezone/gzvm_vm.c        | 107 ++++++++++++++++++++++++
 include/linux/gzvm_drv.h                |  26 ++++++
 include/uapi/linux/gzvm.h               |  25 ++++++
 8 files changed, 217 insertions(+), 1 deletion(-)
 create mode 100644 drivers/virt/geniezone/gzvm_vm.c
 create mode 100644 include/uapi/linux/gzvm.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 682396176290..ee7cc8cd7622 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8988,6 +8988,7 @@ F:	Documentation/virt/geniezone/
 F:	arch/arm64/geniezone/
 F:	drivers/virt/geniezone/
 F:	include/linux/gzvm_drv.h
+F:	include/uapi/linux/gzvm.h
 
 GENWQE (IBM Generic Workqueue Card)
 M:	Frank Haverkamp <haver@linux.ibm.com>
diff --git a/arch/arm64/geniezone/gzvm_arch_common.h b/arch/arm64/geniezone/gzvm_arch_common.h
index f5bddcfe3a1f..fdaa7849353d 100644
--- a/arch/arm64/geniezone/gzvm_arch_common.h
+++ b/arch/arm64/geniezone/gzvm_arch_common.h
@@ -9,6 +9,8 @@
 #include <linux/arm-smccc.h>
 
 enum {
+	GZVM_FUNC_CREATE_VM = 0,
+	GZVM_FUNC_DESTROY_VM = 1,
 	GZVM_FUNC_PROBE = 12,
 	NR_GZVM_FUNC,
 };
@@ -19,6 +21,8 @@ enum {
 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_64,	\
 			   SMC_ENTITY_MTK, (GZVM_FUNCID_START + (func)))
 
+#define MT_HVC_GZVM_CREATE_VM		GZVM_HCALL_ID(GZVM_FUNC_CREATE_VM)
+#define MT_HVC_GZVM_DESTROY_VM		GZVM_HCALL_ID(GZVM_FUNC_DESTROY_VM)
 #define MT_HVC_GZVM_PROBE		GZVM_HCALL_ID(GZVM_FUNC_PROBE)
 
 /**
@@ -41,4 +45,9 @@ int gzvm_hypcall_wrapper(unsigned long a0, unsigned long a1,
 			 unsigned long a6, unsigned long a7,
 			 struct arm_smccc_res *res);
 
+static inline u16 get_vmid_from_tuple(unsigned int tuple)
+{
+	return (u16)(tuple >> 16);
+}
+
 #endif /* __GZVM_ARCH_COMMON_H__ */
diff --git a/arch/arm64/geniezone/vm.c b/arch/arm64/geniezone/vm.c
index e313aadec212..a15bad13c2ee 100644
--- a/arch/arm64/geniezone/vm.c
+++ b/arch/arm64/geniezone/vm.c
@@ -7,9 +7,12 @@
 #include <linux/err.h>
 #include <linux/uaccess.h>
 
+#include <linux/gzvm.h>
 #include <linux/gzvm_drv.h>
 #include "gzvm_arch_common.h"
 
+#define PAR_PA47_MASK ((((1UL << 48) - 1) >> 12) << 12)
+
 /**
  * gzvm_hypcall_wrapper() - the wrapper for hvc calls
  * @a0: arguments passed in registers 0
@@ -45,3 +48,29 @@ int gzvm_arch_probe(void)
 
 	return 0;
 }
+
+/**
+ * gzvm_arch_create_vm() - create vm
+ * @vm_type: VM type. Only supports Linux VM now.
+ *
+ * Return:
+ * * positive value	- VM ID
+ * * -ENOMEM		- Memory not enough for storing VM data
+ */
+int gzvm_arch_create_vm(unsigned long vm_type)
+{
+	struct arm_smccc_res res;
+	int ret;
+
+	ret = gzvm_hypcall_wrapper(MT_HVC_GZVM_CREATE_VM, vm_type, 0, 0, 0, 0,
+				   0, 0, &res);
+	return ret ? ret : res.a1;
+}
+
+int gzvm_arch_destroy_vm(u16 vm_id)
+{
+	struct arm_smccc_res res;
+
+	return gzvm_hypcall_wrapper(MT_HVC_GZVM_DESTROY_VM, vm_id, 0, 0, 0, 0,
+				    0, 0, &res);
+}
diff --git a/drivers/virt/geniezone/Makefile b/drivers/virt/geniezone/Makefile
index 8c1f0053e773..066efddc0b9c 100644
--- a/drivers/virt/geniezone/Makefile
+++ b/drivers/virt/geniezone/Makefile
@@ -6,5 +6,5 @@
 
 GZVM_DIR ?= ../../../drivers/virt/geniezone
 
-gzvm-y := $(GZVM_DIR)/gzvm_main.o
+gzvm-y := $(GZVM_DIR)/gzvm_main.o $(GZVM_DIR)/gzvm_vm.o
 
diff --git a/drivers/virt/geniezone/gzvm_main.c b/drivers/virt/geniezone/gzvm_main.c
index f7d4f0646d97..4e7d60067c55 100644
--- a/drivers/virt/geniezone/gzvm_main.c
+++ b/drivers/virt/geniezone/gzvm_main.c
@@ -4,6 +4,7 @@
  */
 
 #include <linux/device.h>
+#include <linux/file.h>
 #include <linux/kdev_t.h>
 #include <linux/miscdevice.h>
 #include <linux/module.h>
@@ -40,7 +41,24 @@ int gzvm_err_to_errno(unsigned long err)
 	return -EINVAL;
 }
 
+static long gzvm_dev_ioctl(struct file *filp, unsigned int cmd,
+			   unsigned long user_args)
+{
+	long ret;
+
+	switch (cmd) {
+	case GZVM_CREATE_VM:
+		ret = gzvm_dev_ioctl_create_vm(user_args);
+		return ret;
+	default:
+		break;
+	}
+
+	return -ENOTTY;
+}
+
 static const struct file_operations gzvm_chardev_ops = {
+	.unlocked_ioctl = gzvm_dev_ioctl,
 	.llseek		= noop_llseek,
 };
 
@@ -62,6 +80,7 @@ static int gzvm_drv_probe(struct platform_device *pdev)
 
 static int gzvm_drv_remove(struct platform_device *pdev)
 {
+	gzvm_destroy_all_vms();
 	misc_deregister(&gzvm_dev);
 	return 0;
 }
diff --git a/drivers/virt/geniezone/gzvm_vm.c b/drivers/virt/geniezone/gzvm_vm.c
new file mode 100644
index 000000000000..d5e850af924a
--- /dev/null
+++ b/drivers/virt/geniezone/gzvm_vm.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2023 MediaTek Inc.
+ */
+
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/kdev_t.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/gzvm_drv.h>
+
+static DEFINE_MUTEX(gzvm_list_lock);
+static LIST_HEAD(gzvm_list);
+
+static void gzvm_destroy_vm(struct gzvm *gzvm)
+{
+	pr_debug("VM-%u is going to be destroyed\n", gzvm->vm_id);
+
+	mutex_lock(&gzvm->lock);
+
+	gzvm_arch_destroy_vm(gzvm->vm_id);
+
+	mutex_lock(&gzvm_list_lock);
+	list_del(&gzvm->vm_list);
+	mutex_unlock(&gzvm_list_lock);
+
+	mutex_unlock(&gzvm->lock);
+
+	kfree(gzvm);
+}
+
+static int gzvm_vm_release(struct inode *inode, struct file *filp)
+{
+	struct gzvm *gzvm = filp->private_data;
+
+	gzvm_destroy_vm(gzvm);
+	return 0;
+}
+
+static const struct file_operations gzvm_vm_fops = {
+	.release        = gzvm_vm_release,
+	.llseek		= noop_llseek,
+};
+
+static struct gzvm *gzvm_create_vm(unsigned long vm_type)
+{
+	int ret;
+	struct gzvm *gzvm;
+
+	gzvm = kzalloc(sizeof(*gzvm), GFP_KERNEL);
+	if (!gzvm)
+		return ERR_PTR(-ENOMEM);
+
+	ret = gzvm_arch_create_vm(vm_type);
+	if (ret < 0) {
+		kfree(gzvm);
+		return ERR_PTR(ret);
+	}
+
+	gzvm->vm_id = ret;
+	gzvm->mm = current->mm;
+	mutex_init(&gzvm->lock);
+
+	mutex_lock(&gzvm_list_lock);
+	list_add(&gzvm->vm_list, &gzvm_list);
+	mutex_unlock(&gzvm_list_lock);
+
+	pr_debug("VM-%u is created\n", gzvm->vm_id);
+
+	return gzvm;
+}
+
+/**
+ * gzvm_dev_ioctl_create_vm - Create vm fd
+ * @vm_type: VM type. Only supports Linux VM now.
+ *
+ * Return: fd of vm, negative if error
+ */
+int gzvm_dev_ioctl_create_vm(unsigned long vm_type)
+{
+	struct gzvm *gzvm;
+
+	gzvm = gzvm_create_vm(vm_type);
+	if (IS_ERR(gzvm))
+		return PTR_ERR(gzvm);
+
+	return anon_inode_getfd("gzvm-vm", &gzvm_vm_fops, gzvm,
+			       O_RDWR | O_CLOEXEC);
+}
+
+void gzvm_destroy_all_vms(void)
+{
+	struct gzvm *gzvm, *tmp;
+
+	mutex_lock(&gzvm_list_lock);
+	if (list_empty(&gzvm_list))
+		goto out;
+
+	list_for_each_entry_safe(gzvm, tmp, &gzvm_list, vm_list)
+		gzvm_destroy_vm(gzvm);
+
+out:
+	mutex_unlock(&gzvm_list_lock);
+}
diff --git a/include/linux/gzvm_drv.h b/include/linux/gzvm_drv.h
index 907f2f984de9..f1dce23838e4 100644
--- a/include/linux/gzvm_drv.h
+++ b/include/linux/gzvm_drv.h
@@ -6,6 +6,12 @@
 #ifndef __GZVM_DRV_H__
 #define __GZVM_DRV_H__
 
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/gzvm.h>
+
+#define INVALID_VM_ID   0xffff
+
 /*
  * These are the definitions of APIs between GenieZone hypervisor and driver,
  * there's no need to be visible to uapi. Furthermore, we need GenieZone
@@ -17,9 +23,29 @@
 #define ERR_NOT_IMPLEMENTED     (-27)
 #define ERR_FAULT               (-40)
 
+/*
+ * The following data structures are for data transferring between driver and
+ * hypervisor, and they're aligned with hypervisor definitions
+ */
+
+struct gzvm {
+	/* userspace tied to this vm */
+	struct mm_struct *mm;
+	/* lock for list_add*/
+	struct mutex lock;
+	struct list_head vm_list;
+	u16 vm_id;
+};
+
+int gzvm_dev_ioctl_create_vm(unsigned long vm_type);
+
 int gzvm_err_to_errno(unsigned long err);
 
+void gzvm_destroy_all_vms(void);
+
 /* arch-dependant functions */
 int gzvm_arch_probe(void);
+int gzvm_arch_create_vm(unsigned long vm_type);
+int gzvm_arch_destroy_vm(u16 vm_id);
 
 #endif /* __GZVM_DRV_H__ */
diff --git a/include/uapi/linux/gzvm.h b/include/uapi/linux/gzvm.h
new file mode 100644
index 000000000000..c26c7720fab7
--- /dev/null
+++ b/include/uapi/linux/gzvm.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2023 MediaTek Inc.
+ */
+
+/**
+ * DOC: UAPI of GenieZone Hypervisor
+ *
+ * This file declares common data structure shared among user space,
+ * kernel space, and GenieZone hypervisor.
+ */
+#ifndef __GZVM_H__
+#define __GZVM_H__
+
+#include <linux/const.h>
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/* GZVM ioctls */
+#define GZVM_IOC_MAGIC			0x92	/* gz */
+
+/* ioctls for /dev/gzvm fds */
+#define GZVM_CREATE_VM             _IO(GZVM_IOC_MAGIC,   0x01) /* Returns a Geniezone VM fd */
+
+#endif /* __GZVM_H__ */
-- 
2.18.0