Re: [PATCH v9 05/21] virt: geniezone: Add vm support

From: AngeloGioacchino Del Regno
Date: Thu Feb 01 2024 - 04:44:29 EST

Il 29/01/24 09:32, Yi-De Wu ha scritto:
From: "Yingshiuan Pan" <yingshiuan.pan@xxxxxxxxxxxx>

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@xxxxxxxxxxxx>
Signed-off-by: Jerry Wang <ze-yu.wang@xxxxxxxxxxxx>
Signed-off-by: Liju Chen <liju-clr.chen@xxxxxxxxxxxx>
Signed-off-by: Yi-De Wu <yi-de.wu@xxxxxxxxxxxx>
---
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 0cb2d0599469..3ecac8794ba9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9022,6 +9022,7 @@ 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@xxxxxxxxxxxxx>
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_CREATE_VM,
GZVM_FUNC_DESTROY_VM,

The first one will always be zero by default, subsequent members are always
incremental anyway.

+ 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);

As far as I can understand, this tuple is a union of two u16.

If you add that union, you won't even need this function anymore.

+}
+
#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)

This value is unused. Anyway, isn't this just GENMASK_ULL(47, 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;

return gzvm_dev_ioctl_create_vm(user_args);

+ 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 @@

.snip..

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*/

Why are you not using kerneldoc to document this structure?

After all, you're already partially documenting it.

+ 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);

Why is there a trailing space on this function sig?

Regards,
Angelo