KR20210061108A - Virtualization system and data exchange method between host and guest in the sytstem - Google Patents

Abstract

A virtualization system and a method of exchanging data between a host and a guest in the system are disclosed. According to the method of exchanging data, first, a system call defined in a kernel area of a guest OS is called by a specific application in a user area of the guest OS, where the system call includes an identifier of a hypercall defined in the kernel area of the host OS. Next, by the system call, the identifier of the hypercall is used to call the hypercall, so that information related to specific data in the user area of the guest OS is transferred to the hypercall, where the information related to the specific data includes a memory address for storing the specific data. Then, by the hypercall, a kernel buffer is created in the kernel area of the host OS, and by the hypercall, the information related to the specific data is used to copy the specific data in the user area of the guest OS to the kernel buffer.

Description

Virtualization system and data exchange method between host and guest in the system {VIRTUALIZATION SYSTEM AND DATA EXCHANGE METHOD BETWEEN HOST AND GUEST IN THE SYTSTEM}

The present invention relates to a virtualization system and a method of exchanging data between a host and a guest in the system.

Virtualization technology has many advantages, such as reduction of corporate IT infrastructure management costs, ease of application deployment, and utilization and integration of existing servers. Virtualization technology can efficiently manage limited resources by running multiple virtual machines on a physical machine, and improves security for each use environment by using the isolation between each of the driven virtual machines. It is a trend that is widely used in various fields from terminals to large-scale cloud computing.

As one of these virtualization methods, the KVM used in the Linux Kernel-based Virtual Machine (KVM)-based virtualization method is a virtualization platform that uses Linux as a host operating system (hereinafter referred to as "OS"), and is a host OS. In Linux, a virtualization environment is built through the kernel module, and I/O requests from virtual machines are handled using QEMU (Quick Emulator), an open source based machine emulator.

Meanwhile, Linux KVM uses Hypercall to virtualize the guest's Vcpu and vRAM. Here, the hypercall is based on a concept similar to the system call, and is used by the Linux KVM when the guest OS needs to access hardware resources. Such hypercalls, for example, store a value in a CPU register implemented virtually in software, process the stored value, and return it, or receive the guest's memory address and convert the host's real memory address. Used to In other words, in the past, Hypercall was used only to manage virtualized vCPU and vRAM, not IPC (Inter Process Communication).

On the other hand, since the existing data exchange between guest/host was mainly done through the internal socket function and a special virtual device of the hypervisor, virtualization was required for the network bridge as well, and a network port was used for socket communication inside. Therefore, the more guests there are, the more the host's network port is consumed.

In addition, since the buffer size of the network function is very small, there is a problem that many calls to the Send/Receive function occur when transmitting large data, which affects the system performance.

The problem to be solved by the present invention is a virtualization system and a virtualization system capable of controlling a guest in real time and efficient guest/host communication by implementing hyper-calls that can directly communicate with a guest on a hypervisor in the host's kernel. It is to provide a method of exchanging data between the host and the guest.

A data exchange method according to one aspect of the present invention,

A method of exchanging data between a host OS (Operating System) and a guest OS in a virtualization system, wherein in order to copy the data of the guest OS to the host OS, The step of calling a systemcall defined in the kernel area-The system call includes the identifier of the hypercall defined in the kernel area of the host OS -, by the system call, the identifier of the hypercall is used And, by calling the hypercall, information related to specific data in the user area of the guest OS is transferred to the hypercall-the information related to the specific data includes a memory address in which the specific data is stored -, the hypercall By, generating a kernel buffer in the kernel area of the host OS, and copying the specific data in the user area of the guest OS to the kernel buffer by using the memory address by the hypercall. do.

Here, the information related to the specific data further includes size information of the specific data, and the kernel buffer is generated to have a size corresponding to the size information of the specific data.

In addition, when the virtualization system is a Linux-based virtualization system and a Kernel-based Virtual Machine (KVM) is included in the kernel area of the host OS, in the step of being copied to the kernel buffer, the hypercall By doing so, the function of the KVM is used, and the specific data in the user area of the guest OS is copied to the kernel buffer.

In addition, after the step of copying to the kernel buffer, the guest OS is monitored by the kernel region of the host OS through mirroring using data copied to the kernel buffer.

In addition, the information related to the specific data further includes an identifier of the guest OS, and when there are a plurality of the guest OS to which the specific data is to be copied, the kernel buffer to which the specific data is to be copied uses the identifier of the guest OS. It is distinguished.

In addition, the specific data is screen data that the screen of the guest OS is captured by the specific application and stored in a screen buffer in the user area of the guest OS, and the size information of the specific data is information on the horizontal resolution and the vertical resolution of the screen. to be.

Data exchange method according to another aspect of the present invention,

A method of exchanging data between a host OS (operating system) and a guest OS in a virtualization system, wherein to copy control data of the host OS to the guest OS, the guest OS Calling a system call defined in the kernel area of the host OS-The system call includes an identifier of a hypercall defined in the kernel area of the host OS -, by the system call, a memory space in the kernel area of the guest OS A step of allocating, by the system call, the hypercall identifier is used and the hypercall is called, so that the address of the memory space is transferred to the hypercall, by the hypercall, the address of the memory space Is used to copy control data in the kernel region of the host OS into the memory space of the kernel region of the guest OS, and

And transmitting the control data copied to the memory space to a user area of the guest OS by the system call.

Here, the step of transferring the control data to the user area of the guest OS is implemented by injecting the control data copied to the memory space into the device driver area of the kernel area of the guest OS by the system call. .

In addition, when the virtualization system is a Linux-based virtualization system and a Kernel-based Virtual Machine (KVM) is included in the kernel area of the host OS, in the step of copying to the memory space, the hypercall Accordingly, the KVM function is used, and control data of the kernel region of the host OS is copied to the memory space of the kernel region of the guest OS.

In addition, the control data is data of a keyboard event and a mouse event input through the driver area of the kernel area of the host OS, and the control data of the kernel area of the host OS is changed by the system call and the host call. It is injected as control data of the device driver in the kernel area of the OS, and input/output control for the guest OS is possible.

A virtualization system according to another aspect of the present invention directly accesses and controls hardware to provide virtualization, and a host OS (Operating System) composed of a kernel area and a user area, and a user area of the host OS. It is installed in, and includes one or more guest machines consisting of a kernel area and a user area of the guest OS, and to copy data in the user area of the guest OS to the kernel area of the host OS, in the kernel area of the guest OS. A first system call is defined, a first hypercall associated with the first system call is defined in the kernel area of the host OS, and the first system call is called by a specific application in the user area of the guest OS. If yes, the first hypercall associated with the first system call is called, information related to specific data in the user area of the guest OS is transferred to the first hypercall, and the specific data The information related to is used so that specific data in the user area of the guest OS is copied to a kernel buffer created in the kernel area of the host OS by the first hypercall, and the copy of the specific data to the kernel buffer is performed by the first hypercall. The memory address in which the specific data included in the specific data related information is stored is used by the first hypercall and executed.

Here, in order to copy the control data of the kernel area of the host OS to the kernel area of the guest OS, a second system call is additionally defined in the kernel area of the guest OS, and the second system call is added to the kernel area of the host OS. A second hypercall related to the system call is additionally defined, and when the second system call is called by a specific application in the user area of the guest OS, the second hypercall related to the second system call is called. , The address of the memory space allocated to the kernel area of the guest OS by the second system call is transferred to the second hypercall, and the address of the memory space is used by the second hypercall to use the kernel of the host OS. After the control data of the region is copied to the memory space, it is transferred to the user region by the second system call.

In addition, the specific data is screen data that is stored in a screen buffer in a user area of the guest OS after the screen of the guest OS is captured by the specific application.

In addition, the control data is data of a keyboard event and a mouse event input through the driver area of the kernel area of the host OS, and is transmitted to the user area by the second system call by the second system call. The data copied to the memory space is injected as control data of the driver area of the kernel area of the guest OS.

According to an embodiment of the present invention, the host may monitor the guest by using data transmitted from the user area of the guest to the kernel of the host.

In addition, since the control data input from the host can be transmitted to the user area of the guest, the host can control the guest.

In addition, data exchange between the guest and the host can be efficiently performed in a method that has not existed in the past, and in a small and medium-sized real-time system where performance issues are more important than versatility, the system concentration cost can be increased because the load is less than that of the existing method. There is a cost saving effect.

1 is a schematic configuration diagram of a virtualization system according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a concept of defining a hyper call and a system call for data exchange between a host and a guest in the virtualization system illustrated in FIG. 1.
3 is a schematic flowchart of a method of exchanging data between a host and a guest according to an embodiment of the present invention.
4 is a diagram illustrating the method of FIG. 3 applied to a virtualization system.
5 is a schematic flowchart of a method of exchanging data between a host and a guest according to another embodiment of the present invention.
6 is a diagram illustrating the method of FIG. 5 applied to a virtualization system.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary. In addition, terms such as "... unit", "... group", and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. have.

The devices described in the present invention are composed of hardware including at least one processor, a memory device, a communication device, and the like, and a program that is combined with the hardware and executed is stored in a designated place. The hardware has the configuration and capability to implement the method of the present invention. The program includes instructions for implementing the operating method of the present invention described with reference to the drawings, and executes the present invention by combining it with hardware such as a processor and a memory device.

In the present specification, "transmitting or providing" may include not only direct transmission or provision, but also transmission or provision indirectly through another device or using a bypass path.

Expressions described in the singular in this specification may be interpreted as the singular or plural unless an explicit expression such as "one" or "single" is used.

In the present specification, terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another component.

In this specification, an operating system (OS) is a set of programs that provide an interface so that a user can use hardware more easily in a computer device, and resources such as a processor, a storage device, an input/output device, a communication device, and data are To manage, window NT, window 2000, UNIX (Unix), LINUX (Linux), and the like are widely used, and among them, LINUX is used as an example of an OS in this specification.

The system call used in this specification refers to an interface for accessing the kernel according to the request of an application program for a service provided by the kernel of the OS.

Hereinafter, a method of exchanging data between a host and a guest in a virtualization system according to an embodiment of the present invention will be described.

1 is a schematic configuration diagram of a virtualization system according to an embodiment of the present invention.

Referring to FIG. 1, a virtualization system according to an embodiment of the present invention includes, for example, from a host OS 100 and a host OS that directly access and control hardware to provide Linux-based KVM-based virtualization. It includes a guest OS 200 that uses the allocated hardware resources. Here, the guest OS 200 may be at least one or more, and may constitute one guest machine. In addition, the guest OS 200 may be an OS supporting KVM, such as Ubuntu, Centos, and Android using a Linux kernel. Meanwhile, in FIG. 1, only components used only in the embodiments of the present invention are shown in order to simplify the description, but the present invention is not limited thereto.

The host OS 100 and the guest OS 200 are divided into a kernel area and a user area, respectively. That is, the host OS 100 is divided into a host kernel area 110 and a host user area 120, and the guest OS 200 is divided into a guest kernel area 210 and a guest user area 220.

Since the present invention follows the Linux KVM-based virtualization method, the host kernel area 110 is equipped with a KVM 300, which is a kernel module that allows the Linux kernel OS 100 to function as a type-1 hypervisor.

FIG. 2 is a diagram illustrating a concept of defining a hyper call and a system call for data exchange between a host and a guest in the virtualization system illustrated in FIG. 1.

Referring to FIG. 2, hypercalls 310 and 320 for mutual communication are defined for data exchange between a host and a guest in the KVM 300 in the host kernel area 110. In this case, the defined hypercall 310 is a hypercall for transferring user data of the guest user area 220 to the host kernel area 110, and the hypercall 320 is control data of the host kernel area 110 May be defined separately as hypercalls for delivering to the guest kernel area 210. In this case, the hypercalls 310 and 320 need to define multiple hypercalls having the same function according to the type of CPU of the guest machine. The definition of the hypercalls 310 and 320 may be implemented by modifying the kernel.

For example, as an example of transmitting data from the guest OS 200 to the host OS 100, the user application in the guest user area 220 captures screen information and transmits the data to the host OS 100 In the case of exchange, the following hypercall 310 may be defined.

#define KVM_HC_CAPTURESCREEN

The function body of the hypercall 310 described above is defined and implemented in the host kernel area 110, specifically the KVM 300, but the ID (integer) macro of the hypercall 310 is stored in the guest kernel area 210. For reference, the guest kernel area 210 must also be defined as a macro.

On the other hand, since the hypercall 310 defined in the host kernel area 110 cannot be called in the guest user area 220, the privileged area so that the hypercall 310 in the host kernel area 110 can be called, That is, a system call 211 that enables access to the guest kernel area 210 needs to be defined. At this time, the system call 211 is defined in a memory space in the guest kernel area 210.

As described above, in the embodiment of the present invention, the hypercall 310 and the system call 211 for calling the hypercall 310 for data exchange and control between the host OS 100 and the guest OS 200 must be implemented in pairs.

Referring to the above example, the following system call 211 may be defined in order to capture screen information in the guest user area 220 and transmit it to the hypercall 310 of the KVM 300.

#define SYSCALL_CALL_HC_CAPTURE

As an example of the above-described system call 211, it may be defined as follows.

SYSCALL_DEFINE4(SYSCALL_CALL_HC_CAPTURE, int __user, nIndex, unsigned char __user *, pFrame, int __user *, nWidth, int __user *, nHeight)

{

int kWidth;

int kHeight;

int kIndex;

kWidth = g_kFBcapture.nWidth;

kHeight = g_kFBcapture.nHeight;

if(g_isAllocated==1)

{

if(g_isFBUpdating == 0)

{

copy_to_user(pFrame, g_kFBcapture.pFbData, g_kFBcapture.nHeight * g_kFBcapture.nWidth * 4);

}

else

{

copy_to_user(pFrame, g_kFBcapture.pFbDB, g_kFBcapture.nHeight * g_kFBcapture.nWidth * 4);

}

//printk("copy done.");

copy_to_user(nWidth, &kWidth, sizeof(kWidth));

copy_to_user(nHeight, &kHeight, sizeof(kHeight));

}

else

{

printk("Kernel space memory is not allocated!");

}

kvm_hypercall3(KVM_HC_INJECTEVENT, nIndex, pFrame, nWidth, nHeight);

return 0;

}

--------------

SYSCALL_DEFINE2(SYSCALL_CALL_HC_CAPTURE, int __user,nEventType, unsigned char __user *, pEventData,)

{

kvm_hypercall1(KVM_HC_CAPTURESCREEN, &nEventType, pEventData);

return 0;

}

The system call 211 of the above-described example is called to transmit screen information of the guest OS 200, in particular, screen capture information of the guest user area 220 to the host OS 100. It conveys the horizontal resolution, vertical resolution, screen buffer, guest ID, etc. Here, the screen buffer means address information of the screen buffer.

Next, as an example of transferring data from the host OS 100 to the guest OS 200, the host OS 100 transfers control information such as keyboard and mouse information to the guest OS 200. In this case, the above-described hypercall 320 may be defined as follows.

#define KVM_HC_INJECTEVENT

The hypercall 320 defined as described above may also be defined in a form added to the existing hypercall 310 as follows. Below, examples of hypercalls 310 and 320 defined according to an embodiment of the present invention are shown in bold.

#define KVM_HC_VAPIC_POLL_IRQ　　1

#define KVM_HC_MMU_OP　　　2

#define KVM_HC_FEATURES　　　3

#define KVM_HC_PPC_MAP_MAGIC_PAGE　4

#define KVM_HC_KICK_CPU　　　5

#define KVM_HC_MIPS_GET_CLOCK_FREQ　6

#define KVM_HC_MIPS_EXIT_VM　　7

#define KVM_HC_MIPS_CONSOLE_OUTPUT　8

#define KVM_HC_CLOCK_PAIRING　　9

#define KVM_HC_CAPTURESCREEN　　10

#define KVM_HC_INJECTEVENT　　　11

Similarly, the function body of the hypercall 320 described above is also defined and implemented in the host kernel area 110, specifically the KVM 300, but the ID (integer) macro of the hypercall 310 is used in the guest kernel area 210 ) Must be defined as a macro in the guest kernel area 210 as well.

In addition, a system call 212 that calls the above-described hypercall 320 for obtaining control information of the host OS 200 from the guest user area 220 may be additionally defined as follows.

#define SYSCALL_CALL_HC_INJECT

The system call of the above example is called to get a keyboard/mouse event (here, the event means event data) from the host OS 100, and the guest kernel to receive the ID of the hypercall, the mouse event, and the keyboard event. Information such as a memory address of the area 210 is transmitted.

Meanwhile, as described above, in order to exchange data between the host OS 100 and the guest OS 200 periodically, the guest OS 100 needs to be called periodically. Since the system calls (211, 212) defined in the guest kernel area 210 must be called in each specific period, for example, 30, 60, 90 fps (frame per second), or 33 ms/16 ms/11 ms It may be implemented to call the corresponding system calls 211 and 212 periodically.

Hereinafter, a method of exchanging data between the host OS 100 and the guest OS 200 according to an embodiment of the present invention will be described in detail with reference to the drawings.

Here, a method of transferring data from the guest OS 200 to the host OS 100 will be described. In order to facilitate explanation of this method, the above-described example is used. That is, here, the screen information of the guest OS 200, that is, data stored in the screen buffer 221 in which the screen capture data of the screen in the guest user area 220 is stored, is the host OS 100, that is, the host kernel area. Although the method of transferring to (110) will be described, the present invention is not limited to this example.

3 is a schematic flowchart of a method for exchanging data between a host and a guest according to an embodiment of the present invention, and FIG. 4 is a diagram illustrating the method according to FIG. 3 applied to a virtualization system.

First, while the user application 221 in the guest user area 220 performs screen capture and stores the acquired screen data in the screen buffer 222 (S100), the screen data is transferred to the host OS 100 In order to do so, the system call 211 defined in the guest kernel area 210 is called (S110). At this time, the system call 211 to be called is, for example, the aforementioned HC_CAPTURE. Also, these calls can be made periodically.

Since the ID of the corresponding hypercall 310 is included in the called system call 211, the hypercall 310 in the host kernel area 110 is called by the system call 211 (S120), and screen information, that is, The horizontal and vertical resolution information of the screen, the memory address of the screen buffer 222, and the guest ID are transmitted to the hypercall 310 (S120).

The hypercall 310 called from the host kernel area 110 generates a kernel buffer 111 in the host kernel area 110 according to the received screen information (S130). Optionally, the kernel buffer may be generated to have a size corresponding to the horizontal resolution and vertical resolution information of the screen information. In addition, the hypercall 310 defined in the called KVM 300 is the aforementioned HC_CAPTURESCREEN.

Thereafter, the hypercall 310 of the host kernel area 110 accesses the screen buffer 222 in the guest user area 220 using the memory address of the screen buffer 222 and stores the screen in the screen buffer 222. The data is copied to the kernel buffer 111 in the host kernel area 110 (S140). In this case, accessing the screen buffer 222 in the guest user area 220 using the memory address of the screen buffer 222 in the host kernel area 110 may be implemented through, for example, a kvm_read_guest_mmu function. Also, the kernel buffer 111 can be identified through a guest ID.

As described above, in the present invention, the system call 211 defined in the guest kernel area 210 and the hypercall 310 defined in the KVM 300 of the host kernel area 110 are used to control the guest user area 220. Since screen data can be transferred to the host kernel area 110, the host OS 100 can monitor the guest OS 200 using the screen data. For example, monitoring of the guest OS 200 may be performed through mirroring using xwindows/qt/opencv or the like.

Next, a method of transferring data from the host OS 100 to the guest OS 200 will be described. In order to facilitate explanation of this method, the above-described example is used. That is, here, a method of transmitting control information of the host OS 100, specifically a keyboard event and a mouse event, to the guest OS 200, that is, the guest user area 220 will be described.

5 is a schematic flowchart of a method of exchanging data between a host and a guest according to another embodiment of the present invention, and FIG. 6 is a diagram illustrating the method of FIG. 5 applied to a virtualization system.

First, the user application 221 in the guest user area 220 calls the system call 212 defined in the guest kernel area 210 to get keyboard events and mouse events from the host kernel area 110. (S200). At this time, the system call 212 to be called is HC_INJECT described above. In addition, the system call 212 may be called periodically.

The called system call 212 is allocated a memory space 214 to receive keyboard events and mouse events in the guest kernel area 210 (S210).

On the other hand, since the ID of the corresponding hypercall 320 is included in the system call 212, the hypercall 320 in the host kernel area 110 is called by the system call 212, and keyboard events and mouse events are displayed. The memory address of the memory space 214 to be transmitted is transmitted (S220). Here, the hypercall 320 defined in the called host kernel area 110 is the aforementioned HC_INJECTEVENT.

Thereafter, the hypercall 320 called from the host kernel area 110 is the driver area 112 into which keyboard and mouse event information of the host OS 100 is input, for example, a device driver, /dev/input/ The keyboard events and mouse events are read from the event and copied to the memory space 214 allocated to the guest kernel area 210 by using the address of the memory space 214 (S230). In this case, copying the keyboard event and mouse event information of the host OS 100 to the memory space 214 allocated to the guest kernel area 210 may be implemented through, for example, a kvm_write_guest_mmu function.

Thereafter, the system call 212 of the guest kernel area 210 transmits keyboard events and mouse events copied to the memory space 214 to the driver area 215 in the guest kernel area 210, for example, a device driver, Guest Inject to /dev/event (S240). Through such injection, a keyboard event and a mouse event generated in the host kernel area 110 may be transmitted to the user application 221.

As described above, in the present invention, the system call 212 defined in the guest kernel area 210 and the hyper call 320 defined in the KVM 300 of the host kernel area 110 are used to control the host kernel area 110. Since control data can be transferred to the guest user area 220, the host OS 100 can control the guest OS 200, for example, input/output (I/O) control.

Meanwhile, data that can be transferred from the guest OS 200 to the host OS 100 through the system calls 211 and 212 and the hyper calls 310 and 320 as described above are files (including media files) and the guest OS ( 200) is the system status of the guest OS 200 for monitoring, and on the contrary, from the host OS 100 to the guest OS 200, the host OS 100 triggers the guest OS 200 to perform a specific function. Control information can be delivered to enable the user to hang.

The embodiments of the present invention described above are not implemented only through an apparatus and a method, but may be implemented through a program that realizes a function corresponding to the configuration of the embodiment of the present invention or a recording medium in which the program is recorded.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (14)

As a method of exchanging data between a host OS (Operating System) and a guest OS in a virtualization system,
In order to copy the data of the guest OS to the host OS, a systemcall defined in the kernel area of the guest OS is called by a specific application running in the guest OS.- The system call is the host Contains the identifier of the hypercall defined in the kernel area of the OS -,
By the system call, the hypercall identifier is used and the hypercall is called, so that information related to specific data in the user area of the guest OS is transferred to the hypercall.- The information related to the specific data is Contains the memory address where the data is stored -,
By the hypercall, generating a kernel buffer in the kernel area of the host OS, and
By the hypercall, the memory address is used and the specific data in the user area of the guest OS is copied to the kernel buffer.
Data exchange method comprising a. The method of claim 1,
The information related to the specific data further includes size information of the specific data,
The kernel buffer is created to have a size corresponding to the size information of the specific data,
How to exchange data. The method of claim 1,
When the virtualization system is a Linux-based virtualization system and a Kernel-based Virtual Machine (KVM) is included in the kernel area of the host OS,
In the step of copying to the kernel buffer, by the hypercall, the function of the KVM is used so that the specific data in the user area of the guest OS is copied to the kernel buffer,
How to exchange data. The method of claim 3,
After the step of being copied to the kernel buffer,
Monitoring of the guest OS is performed through mirroring using data copied to the kernel buffer by the kernel region of the host OS,
How to exchange data. The method of claim 1,
The information related to the specific data further includes an identifier of the guest OS,
When there are a plurality of guest OSs to which the specific data is to be copied, a kernel buffer to which the specific data is to be copied is identified using an identifier of the guest OS,
How to exchange data. The method according to any one of claims 1 to 5,
The specific data is screen data that the screen of the guest OS is captured by the specific application and stored in a screen buffer in the user area of the guest OS,
The size information of the specific data is information on the horizontal resolution and the vertical resolution of the screen,
How to exchange data. As a method of exchanging data between a host OS (Operating System) and a guest OS in a virtualization system,
In order to copy the control data of the host OS to the guest OS, a system call defined in the kernel area of the guest OS is called by a specific application running in the guest OS.- The system call Contains the hypercall identifier defined in the kernel area -,
Allocating a memory space in the kernel area of the guest OS by the system call,
By the system call, the hypercall identifier is used and the hypercall is called, so that the address of the memory space is transferred to the hypercall,
By the hypercall, the address of the memory space is used and control data in the kernel region of the host OS is copied to the memory space of the kernel region of the guest OS, and
Transferring the control data copied to the memory space to the user area of the guest OS by the system call
Data exchange method comprising a. The method of claim 7,
The step of transferring the control data to the user area of the guest OS,
By the system call, the control data copied to the memory space is implemented by injecting into the device driver area of the kernel area of the guest OS,
How to exchange data. The method of claim 7,
When the virtualization system is a Linux-based virtualization system and a Kernel-based Virtual Machine (KVM) is included in the kernel area of the host OS,
In the step of copying to the memory space, the KVM function is used by the hypercall, so that control data of the kernel region of the host OS is copied to the memory space of the kernel region of the guest OS,
How to exchange data. The method according to any one of claims 7 to 9,
The control data is data of a keyboard event and a mouse event input through a driver area of the kernel area of the host OS,
By the system call and the host call, control data of the kernel area of the host OS is injected as control data of the device driver of the kernel area of the guest OS, so that input/output control for the guest OS is possible,
How to exchange data. As a virtualization system,
To provide virtualization, it directly accesses the hardware and performs control, and the host OS (Operating System) consisting of a kernel area and a user area, and
One or more guest machines installed in the user area of the host OS and composed of a kernel area and a user area of the guest OS
Including,
In order to copy data in the user area of the guest OS to the kernel area of the host OS, a first system call is defined in the kernel area of the guest OS, and is associated with the first system call in the kernel area of the host OS. The first hypercall is defined,
When the first system call is called by a specific application in the user area of the guest OS, the first hypercall associated with the first system call is called, so that information related to specific data in the user area of the guest OS is Delivered to the first hypercall,
Information related to the specific data is used by the first hypercall, so that specific data in the user area of the guest OS is copied to a kernel buffer created in the kernel area of the host OS by the first hypercall,
The copying of the specific data to the kernel buffer is performed by using a memory address in which the specific data included in the information related to the specific data is stored is used by the first hypercall,
Virtualization system. The method of claim 11,
In order to copy the control data of the kernel area of the host OS to the kernel area of the guest OS, a second system call is additionally defined in the kernel area of the guest OS, and the second system call is included in the kernel area of the host OS. A second hypercall associated with is additionally defined,
When the second system call is called by a specific application in the user area of the guest OS, the second hypercall associated with the second system call is called, and the kernel area of the guest OS is called by the second system call. The address of the allocated memory space is transferred to the second hypercall,
After the address of the memory space is used by the second hypercall and control data of the kernel region of the host OS is copied to the memory space, it is transferred to the user region by the second system call,
Virtualization system. The method of claim 11,
The specific data is screen data that the screen of the guest OS is captured by the specific application and stored in a screen buffer in a user area of the guest OS,
Virtualization system. The method of claim 12,
The control data is data of a keyboard event and a mouse event input through a driver area of the kernel area of the host OS,
Delivered to the user area by the second system call,
The data copied to the memory space by the second system call is injected as control data of the driver region of the kernel region of the guest OS,
Virtualization system.

Images