CN116821033A - A PCIe equipment control method and device - Google Patents

Abstract

The present application relates to a PCIe equipment control method and device. The method includes: when a bridge device is scanned from the system, determining whether the bridge device supports hot plugging; when the bridge device supports hot plugging, assigning an identifier to a slot connected to the bridge device; The identifier is a unique identifier; assign the identifier of the slot to the terminal device in the slot, and initialize the terminal device through the device driver. Using this method, in the process of device scanning, a unique identifier is assigned in advance to the slot connected to the bridge device that supports hot plugging. When the terminal device is inserted into the slot, the identifier of the slot is assigned to the terminal device. This prevents drive letter drift caused by the hot-swap operation of terminal equipment.

Description

A PCIe equipment control method and device

Technical field

The present application relates to the field of PCIe device control, and in particular to a PCIe device control method and device.

Background technique

PCIe (peripheral component interconnect express) is the third generation I/O bus standard after the PCI bus. Its main advantages over the PCI bus are high data transmission rate, strong anti-interference ability, long transmission distance and Lower power consumption. PCIe is widely used in consumer computer equipment, enterprise large servers, and switch systems. Equipment using PCIe is called PCIe equipment.

With the development of science and technology, the performance requirements for computers are getting higher and higher. While computers are required to have fast computing capabilities, they are also required to have powerful storage capabilities. Among them, the computing power mainly depends on the computer CPU, and the storage capacity mainly depends on the hard disk. When the performance of both reaches a certain level, the processing power of the entire computer depends on its data processing ability. In order to meet faster and higher data processing requirements, the hard disk interface standard NVME (non-volatile memory express, non-volatile memory host controller interface specification) was born. Hard disks that meet this standard are called NVME hard disks.

When using a computer system, if a component is damaged, such as a disk, it is often necessary to power off the system before it can be replaced. For large systems, once the power is cut off and operations cease, it will have a serious impact. In order to avoid frequent power outages affecting operations of large-scale systems, hot-swap technology is proposed. This technology includes hot-add and hot-deletion operations. Hot-swap technology can replace hard disks without power interruption. Most current operating systems support NVME hot-plug technology. When a device is hot-plugged into the system, the hot-plug driver is triggered by interrupts to perform different actions.

However, the existing method of adding character devices has the problem of drive letter drift. For example: there is device nvme1 inserted in slot 1, and the corresponding drive letter ID of this device is 1; there is device nvme2 inserted in slot 2, and the corresponding drive letter ID of this device is 2. At this time, the corresponding relationship between character devices in the operating system is: The character device /dev/nvme1 points to the nvme1 disk, and the character device /dev/nvme2 points to the nvme2 disk. After unplugging device nvme1 and device nvme2, insert device nvme2 first, and then insert device nvme1. Then the drive letter ID of device nvme2 changes to 1, and the drive letter ID of device nvme1 changes to 2. At this time, the character device under the operating system also Corresponding changes will occur: the character device /dev/nvme1 actually points to the nvme2 disk, and the character device /dev/nvme2 actually points to the nvme1 disk. Because the identifier of nvme1 has changed to 2, this is a very serious error for the upper-layer business. When the drive letter drifts, the business configuration needs to be changed to make the business proceed normally. This is not suitable for uninterruptible business. It's catastrophic. Therefore, it is necessary to find a way to prevent the hot-swap operation of the device from causing drive letter drift and thus affecting the normal operation of upper-layer services.

Contents of the invention

In view of this, this application aims to propose a PCIe device control method and device to solve the problem of drive letter drift caused by device hot-plug operation.

The first aspect of the embodiment of the present application provides a PCIe device control method, the method includes:

When a bridge device is scanned from the system, determine whether the bridge device supports hot plugging;

When the bridge device supports hot plugging, assign an identifier to the slot connected to the bridge device; the identifier is a unique identifier;

The identifier of the slot is assigned to the terminal device in the slot, and the terminal device is initialized through the device driver.

Optionally, when a bridge device is scanned from the system, determine whether the bridge device supports hot plugging, including:

Query whether the bridge device has enabled the interrupt function; the interrupt function includes MSI interrupt and MSI-X interrupt;

If the interrupt function is enabled on the bridge device, the register of the bridge device is further read to determine whether the bridge device supports hot swapping;

If the bridge device does not enable the interrupt function, the bridge device does not support hot plugging.

Optionally, assign an identifier to the slot to which the bridge device is connected, including:

Add a variable for storing the identifier of the slot to the data structure corresponding to the bridge device;

Get an identifier and store the identifier into the variable.

Optionally, assigning the identifier of the slot to the terminal device in the slot includes:

In the device driver, perform an operation of obtaining the bridge device connected to the slot;

Read the variable storing the identifier of the slot from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable;

An identifier of the slot is assigned to the terminal device.

Optionally, assign an identifier to the slot to which the bridge device is connected, including:

In the device driver, perform an operation of adding a variable used to save the identifier of the slot to the data structure corresponding to the bridge device;

Get an identifier and store the identifier into the variable.

Optionally, assigning the identifier of the slot to the terminal device in the slot includes:

In the device driver, perform an operation of obtaining the bridge device connected to the slot;

Read the variable holding the identifier of the slot from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable;

An identifier of the slot is assigned to the terminal device.

Optionally, the PCIe device control method also includes:

When the system starts, initialize the system configuration;

Initialize the data structure of the PCIe device and generate a data structure used to describe the PCIe device information; the data structure describing the PCIe device information includes: the bus to which the device belongs, device type and device ID; the data structure describing the PCIe device information is a tree like structure;

Scan the devices in the system and determine the type of the currently scanned device; the device is a bridge device or a terminal device, and any terminal device is connected to a bridge device one-to-one.

Optionally, the PCIe device control method also includes:

Allocate corresponding device resources to the currently scanned terminal device; the device resources include bus resources and memory resources;

Call the bus detection interface to match the corresponding device driver for the terminal device.

Optionally, the PCIe device control method also includes:

When the bridge device supports hot plugging, resources to be allocated are reserved for the bridge device; the resources to be allocated include bus resources and memory resources;

When the bridge device does not support hot plugging, return and continue scanning other devices in the system.

Optionally, the PCIe device control method also includes:

When the bridge device supports hot plugging, create an interrupt callback function;

Create an interrupt work queue and event processing callback function through the interrupt callback function;

The event processing callback function performs add or delete operations based on the hot plug behavior of the terminal device in the system, including:

Obtain interrupt information through the event processing callback function and determine the interrupt type;

If the interrupt type is device addition, rescan the devices in the system, and when the newly added terminal device is scanned, call the device driver;

Execute in the device driver the operation of obtaining the bridge device connected to the slot where the newly added terminal device is located;

Read the variable holding the identifier of the slot where the newly added terminal device is located from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable;

Assign the identifier of the slot to the newly added terminal device;

Initialize the newly added terminal device in the device driver;

If the interruption type is device deletion, call the delete operation function to stop the corresponding terminal device, delete the corresponding data in the data structure corresponding to the bridge device connected to the terminal device, and release the device resources allocated to the terminal device. ; The device resources include bus resources and memory resources.

According to the second aspect of the embodiment of the present application, a PCIe device control device is provided for implementing the PCIe device control method provided by the first aspect of the embodiment of the present application. The device includes:

A device scanning module configured to determine whether the bridge device supports hot swap when a bridge device is scanned from the system;

An identifier allocation module configured to allocate an identifier to a slot connected to the bridge device when the bridge device supports hot plugging;

The device initialization module is configured to allocate the identifier of the slot to the terminal device in the slot, and initialize the terminal device through a device driver.

Using the PCIe device control method provided by this application, when a bridge device is scanned in the system, it is judged whether the bridge device supports hot plugging. When the bridge device supports hot plugging, the plug-in connection for the bridge device is determined. The slot is assigned a unique identifier. When a terminal device is inserted into the slot, the slot's identifier can be assigned to the terminal device.

In the PCIe device control method provided by this application, by performing device scanning in the system, it is determined whether the currently scanned bridge device supports hot plugging, and during the device scanning process, a slot is connected to the bridge device that supports hot plugging in advance. Allocate a unique identifier. After the terminal device is inserted into the slot, the identifier of the slot is assigned to the terminal device, thereby preventing the hot-swap operation of the terminal device from causing drive letter drift.

Description of the drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the drawings needed to be used in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. , for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative labor.

Figure 1 is a flow chart of a PCIe device control method proposed by an embodiment of the present application;

Figure 2 is a schematic diagram of a PCIe device control device proposed by an embodiment of the present application;

Figure 3 is a flow chart of PCIe device initialization proposed by an embodiment of the present application;

Figure 4 is a flow chart of PCIe device initialization in related technology;

Figure 5 is a flow chart of hot plug management in an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

It will be understood that reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic associated with the embodiment is included in at least one embodiment of the present application. Thus, the appearances of "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

In the various embodiments of this application, it should be understood that the size of the sequence numbers of the following processes does not mean the order of execution. The execution order of each process should be determined by its functions and internal logic, and should not be implemented in this application. The implementation of the examples does not constitute any limitations.

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings refer to the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with this application. Rather, they are merely examples of apparatus and methods consistent with aspects of the application as detailed in the appended claims.

It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other.

Hot-swap technology is hot-swap technology. Hot-swap technology allows users to remove and replace damaged hard drives, power supplies, boards and other components without shutting down the system or cutting off the power supply. The use of hot-swap technology can improve the reliability of the system. performance, scalability and flexibility, while enabling the system to have rapid repairability, redundancy and timely recovery capabilities from disasters.

Hot plugging of computer systems includes hot addition and hot deletion. Among them, hot add mainly reads the register information of the slot, and determines whether there is a device inserted signal based on the information. If so, continue to further traverse the slot, and finally call the hard disk driver. In the hard disk driver, it will Create files in the system and add devices to complete the initialization of the entire device.

There are character devices and block devices in the system. Character devices refer to devices that are accessed sequentially in a byte stream serial order. Reading and writing to them are in bytes. Common character devices include mice, keyboards, etc.; A block device refers to a device that can read data of a certain length from any location on the device. Common block devices include hard disks, magnetic disks, USB flash drives, etc. Terminal devices in the system are usually character devices. When adding a terminal device, the driver will obtain a unique identification ID through the IDA (a drive letter allocation mechanism) mechanism, and then create the corresponding terminal device based on this identification. This embodiment aims to solve the problem of drive letter drift caused by the hot plug operation of terminal equipment in the system.

For the PCIe initialization process, the devices scanned during the initialization process are divided into two types: terminal devices and bridge devices. Terminal equipment refers to computer external equipment such as hard drives, memory cards, etc. A bridge device is a special device in PCIe. Its main purpose is to expand other types of devices, such as terminal devices and bridge devices. That is, a bridge device can connect to terminal devices and other bridge devices. In this embodiment, all terminal devices are connected to the bridge device one-to-one, and a bridge device that supports hot-swappable devices can only extend one hot-swappable terminal device.

Figure 4 is a flow chart of PCIe device initialization in related art. As shown in Figure 4, under normal circumstances, the system initializes PCI devices as follows:

S1: Initialize the system when the system starts. The system initialization here mainly refers to some settings made after the system is turned on, such as memory initialization, system enabling or disabling certain functions, etc.;

S2: After the system is initialized, the initialization of the PCIe structure begins. This initialization refers to the establishment of a data structure used to describe the PCIe device information in the system. The data structure includes the bus to which the device in the system belongs, device type, device ID, etc. Information, in order to facilitate the management of all PCIe devices, all PCIe device structures will be connected in series to form a tree structure;

S3: After the PCIe structure initialization is completed, enter the device scanning stage. This step is mainly to scan which PCIe devices are in the system;

S4: When a terminal device is scanned, the corresponding device resources will be allocated to the terminal device, and then the device driver will be called to initialize the terminal device;

S5: When a bridge device is scanned, because the bridge device needs to be connected to other devices, some resources will be reserved for the bridge device, such as bus number resources and memory resources;

S6: Initialize the PCIe device, dynamically obtain a unique identifier through the IDA mechanism (calling the IDA interface) in the device driver to identify the uniqueness of the device, and then create the corresponding device.

The IDA mechanism (drive letter allocation mechanism) is a method for the kernel to manage integer resources. It can manage a large number of integer resources and is very efficient when retrieving resources.

In the above step S6, there is a problem of drive letter drift. This is because the device driver dynamically obtains an identifier and assigns it to the terminal device every time it initializes the terminal device. Therefore, once the terminal device is unplugged and re-inserted, , which will cause drive letter drift.

Since the phenomenon of drive letter drift in the system is mainly caused by the hot-swapping operation of the terminal device, whether the bridge device connected to the hot-swappable slot supports hot-swapping can actually be known by scanning the register during the system initialization process. , so before calling the device driver to initialize the connected terminal device, the problem of drive letter drift can be solved by reserving an identifier for the slot in advance. Moreover, the number of external devices connected to an operating system is limited, and the number of storage devices is even more limited. Therefore, reserving identifiers for external devices in advance will not cause a shortage of identifier resources.

The present application will be described in detail below with reference to the accompanying drawings and embodiments.

Figure 1 is a flow chart of a PCIe device control method proposed by an embodiment of the present application. As shown in Figure 1, the method includes:

S11: When a bridge device is scanned from the system, determine whether the bridge device supports hot swapping;

S12: When the bridge device supports hot plugging, assign an identifier to the slot connected to the bridge device; the identifier is a unique identifier;

S13: Assign the identifier of the slot to the terminal device in the slot, and initialize the terminal device through the device driver.

In one embodiment, when the system starts, the device registers in the system are scanned. When a bridge device is scanned, it is determined whether the bridge device supports hot plugging. When it is known that the bridge device supports hot plugging, a unique identifier can be assigned to the slot to which the bridge device is connected. In this embodiment, a bridge device that supports hot swapping is only connected to one slot, that is, one bridge device can only expand one terminal device.

When an external terminal device is inserted into the slot, the identifier of the slot is first assigned to the terminal device, and then subsequent initialization of the terminal device is completed through the device driver corresponding to the terminal device. In this embodiment, when a bridge device is scanned during system initialization, a unique identifier is reserved for the slot to which the bridge device is connected. When a terminal device is inserted into the slot, the unique identifier of the slot can be The drive letter is assigned to the terminal device to solve the problem of drive letter drift.

S111: Query whether the bridge device has enabled the interrupt function; the interrupt function includes MSI interrupt and MSI-X interrupt;

If the interrupt function is enabled on the bridge device, the register of the bridge device is further read to determine whether the bridge device supports hot swapping;

If the bridge device does not enable the interrupt function, the bridge device does not support hot plugging.

In one embodiment, the bridge device is first queried whether the interrupt function is enabled. When it is found that the interrupt function of the bridge device is enabled, the register of the bridge device is further read to determine whether the bridge device supports hot plugging. For example, if the relevant value read in the register is 1, it means that the bridge device supports hot plugging. If the relevant value read in the register is 0, it means the bridge device does not support hot plugging. If the query shows that the bridge device does not have the interrupt function enabled, it means that the bridge device does not support hot swapping.

In this embodiment, the interrupt function enabled by the bridge device may be an MSI interrupt or an MSI-X interrupt. MSI (MessageSignaled Interrupts) is a way to generate interrupts by writing information in memory, where the memory address is negotiated between the device driver and the hardware device. MSI is different from traditional interrupt lines. It does not require a separate interrupt line, but communicates through the PCI bus; MSI-X (Extended Message Signaled Interrupts, Extended Message Signaled Interrupts) is an extension based on MSI Interrupt mode, which allows the device to use multiple independent interrupt signals, thereby improving the efficiency of interrupt processing. Commonly used in applications that require high-speed response, such as virtualization or high-performance computing.

In this embodiment, when the bridge device is scanned, it is first determined whether the interrupt function is enabled on the bridge device, so as to reserve an identifier for the slot connected to the bridge device that enables the interrupt function and supports hot plugging. When the bridge device is not enabled, When the function is interrupted, there is no need to make the next step of judgment, thereby saving system resources and speeding up initialization.

S121: Add a variable for storing the identifier of the slot to the data structure corresponding to the bridge device;

S122: Obtain an identifier and store the identifier into the variable.

In one embodiment, when the system starts scanning for devices within the system, identifiers are assigned to the scanned slots. Specifically, after the bridge device is scanned and it is determined that the bridge device supports hot plugging, it means that the slot connected to the bridge device can be plugged into an external terminal device. At this time, in the data structure formed by the PCIe structure initialization, the bridge device is Add a variable to save the identifier of the slot to which the bridge device is connected in the partial structure corresponding to the device. This variable is used to store the identifier of the slot. This variable can be defined by itself, for example, set the variable name to int32_t instance_id.

When a variable is added to the data structure, an identifier is obtained, which will be used as the unique identifier of the slot, and the identifier is stored in the variable for subsequent reading.

It should be noted that in this embodiment, the method of obtaining the identifier can be to call the IDA interface to obtain the identifier, or to obtain the identifier without using the IDA mechanism. The method of obtaining the identifier in this embodiment is not specifically limited, as long as the identifier is obtained A unique identifier is sufficient.

S131: In the device driver, perform the operation of obtaining the bridge device connected to the slot;

S132: Read the variable storing the identifier of the slot from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable;

S133: Assign the identifier of the slot to the terminal device.

In one embodiment, when the terminal device is initialized, a unique identifier is assigned to the terminal device in the device driver. Specifically, before the device driver initializes the terminal device, the device driver will first obtain the slot where the terminal device is located, and find and obtain the bridge device connected to the slot.

Find the corresponding part from the data structure according to the bridge device, and then read the variables that have been saved in this part of the data structure. This variable is used to save the unique identifier of the slot, that is, the value of the slot is read. Unique identifier.

After reading the slot identifier, the device driver assigns the slot identifier to the terminal device. In this embodiment, the device driver reads the bridge device corresponding to the slot where the terminal device is located, obtains the unique identifier of the slot from the data structure corresponding to the bridge device, and uses the identifier as the terminal device. The identifier of the device makes the identifier of the terminal device depend on the identifier of the slot in which it is located. Therefore, the hot-swap operation of the terminal device will not cause the identifier to change, thereby avoiding drive letter drift.

S121’: In the device driver, perform the operation of adding a variable for storing the identifier of the slot to the data structure corresponding to the bridge device;

S122’: Obtain an identifier and store the identifier into the variable.

In one embodiment, the slot may be assigned a unique identifier directly through the device driver. Specifically, add a program or code statement for assigning an identifier to a slot in the device driver, find the bridge device connected to the slot where the terminal device is located, and add a data structure for saving the slot to the data structure corresponding to the bridge device. Identifier variable. After adding the variable, obtain an identifier that will serve as a unique identifier for the slot and store the identifier in the variable for subsequent reading.

S131’: In the device driver, perform the operation of obtaining the bridge device connected to the slot;

S132’: Read the variable storing the identifier of the slot from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable;

S133': Assign the identifier of the slot to the terminal device.

In one embodiment, after the device driver assigns a unique identifier to the slot, the device driver assigns the slot identifier to the terminal device. Specifically, the device driver obtains the bridge device connected to the slot where the terminal device is located, and reads the variable that holds the unique identifier of the slot from the data structure corresponding to the bridge device, that is, reads the variable of the slot. Unique identifier. The identifier of the slot is used as the identifier of the terminal device, and then the device driver continues to initialize the terminal device.

In this embodiment, an identifier is allocated in the device driver for the slot where the terminal device is located, and the identifier of the slot is assigned to the terminal device, so that the identifier of the terminal device depends on the identifier of the slot where it is located, Therefore, the hot-swappable operation of the terminal device will not cause the identifier to change, thereby avoiding drive letter drift.

In one embodiment, the PCIe device control method further includes:

S101: When the system starts, initialize the system configuration;

S102: Initialize the data structure of the PCIe device and generate a data structure used to describe the PCIe device information; the data structure describing the PCIe device information includes: the bus to which the device belongs, device type and device ID; the data structure describing the PCIe device information It is a tree structure;

S103: Scan the devices in the system and determine the type of the currently scanned device; the device is a bridge device or a terminal device, and any terminal device is connected to a bridge device one-to-one.

In the above embodiment, before the system allocates a unique identifier to the terminal device, the system first needs to perform initial configuration. The initial configuration of the system mainly refers to some settings made after the system is turned on, such as memory initialization, system enabling or disabling certain Function settings, etc.

After system initialization, initialize the PCIe structure. PCIe structure initialization is mainly to establish a data structure describing PCIe device information in the system, which includes the data structure and connection information of each PCIe device. Specifically, it includes the bus to which the device belongs, device type, device ID and other information. In order to facilitate management, in one embodiment, the data structures of PCIe devices are concatenated and formed into a tree structure for management.

After the PCIe data structure is initialized, scan the PCIe devices in the system. Specifically, the register of the device is read. If the data is successfully read, it means that the device exists. The register related to the device type is further read to obtain the type of the device.

S123: Allocate corresponding device resources to the currently scanned terminal device; the device resources include bus resources and memory resources.

In the above embodiment, when a terminal device is scanned, corresponding device resources need to be allocated to the terminal device so that the terminal device can be used normally after subsequent initialization. The resources allocated to terminal devices are usually bus resources and memory resources.

S124: Call the bus detection interface to match the corresponding device driver for the terminal device.

Initializing the terminal device needs to be done through the device driver. In one embodiment, before initializing the device through the device driver, it is also necessary to call the bus detection interface, match the corresponding device driver according to the type of the terminal device, and then execute the terminal device through the corresponding device driver. initialization.

S125: When the bridge device supports hot plugging, reserve resources to be allocated for the bridge device; the resources to be allocated include bus resources and memory resources;

S126: When the bridge device does not support hot plugging, return and continue scanning other devices in the system.

In the above embodiment, when the scanned bridge device supports hot swapping, some resources need to be reserved for the bridge device so that when the terminal device is subsequently connected to an external terminal device through the bridge device, corresponding device resources are allocated to the terminal device. In this embodiment, the resources reserved for the bridge device include bus number resources and memory resources.

S104: When the bridge device supports hot plugging, create an event processing callback function, and the event processing callback function performs an adding or deleting operation according to the hot plugging behavior of the terminal device in the system.

In one embodiment, the hot-plug management of external terminal devices is performed by creating an event processing callback function. In this embodiment, hot-plug management includes addition and deletion. When an external terminal device is inserted into the slot, or there is a terminal When the device is unplugged from the slot, the corresponding operation of adding or deleting the device is performed through the event processing callback function.

Figure 5 is a flow chart of hot plug management in an embodiment of the present application. As shown in Figure 5, in hot-plug management in the system, adding and deleting terminal devices includes the following steps:

S1041: When the bridge device supports hot plugging, create an interrupt callback function, and create an interrupt work queue and event processing callback function through the interrupt callback function.

In one embodiment, when a bridge device is scanned, it is first checked whether the bridge device has an interrupt (MSI interrupt or MSI-X interrupt) function enabled. When the bridge device enables the interrupt function, create an interrupt callback function. The interrupt callback function will further create an interrupt work queue and event processing callback function.

S1042: Obtain interrupt information through the event processing callback function and determine the interrupt type.

In this embodiment, the event processing callback function obtains the interrupt information of the system, such as the interrupt information of device access or device removal.

S1043: If the interrupt type is device addition, rescan the devices in the system, and when the newly added terminal device is scanned, call the device driver;

Execute in the device driver the operation of obtaining the bridge device connected to the slot where the newly added terminal device is located;

Read the variable holding the identifier of the slot where the newly added terminal device is located from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable;

Assign the identifier of the slot to the newly added terminal device;

Initialize the newly added terminal device in the device driver.

In this embodiment, after obtaining the interrupt information of the system, the event processing callback function further determines the type of the interrupt information. If the type of interrupt information is device addition (that is, an event triggered by inserting a disk), the device will be rescanned in the system. If a newly added terminal device is scanned, the device driver will be further called to read the socket where the terminal device is located. The unique identifier of the slot determines the identifier of the terminal device, thereby assigning a unique identifier to the newly added terminal device before the device driver initializes the terminal device to prevent drive letter drift.

The device driver will obtain the identifier of the newly added terminal device through the method provided in the above embodiment, and then create a corresponding character device in the system to complete the adding process of the terminal device.

S1044: If the interrupt type is device deletion, call the delete operation function to stop the corresponding terminal device, delete the corresponding data in the data structure corresponding to the bridge device connected to the terminal device, and release the data allocated to the terminal device. Device resources; the device resources include bus resources and memory resources.

If the type of interrupt information is device deletion (for example: an interrupt event triggered by unplugging the device), the event processing callback function will call the corresponding delete operation function to stop the running process of the unplugged terminal device and delete the unplugged terminal device. Data corresponding to the terminal device and release related resources, for example, delete and release the bus resources and memory resources allocated to the terminal device when the terminal device is initialized for subsequent reallocation for the terminal device newly inserted into the slot.

Based on the same inventive concept, an embodiment of the present application provides a PCIe device control device. Referring to Figure 2, Figure 2 is a schematic diagram of a PCIe device control device 200 proposed by an embodiment of the present application. As shown in Figure 2, the device includes:

The device scanning module 201 is configured to determine whether the bridge device supports hot plugging when scanning a bridge device from the system;

The identifier allocation module 202 is configured to allocate an identifier to the slot connected to the bridge device when the bridge device supports hot plugging;

The device initialization module 203 is configured to assign the identifier of the slot to the terminal device in the slot, and initialize the terminal device through the device driver.

Optionally, the device scanning module 201 also includes a query sub-module configured to query whether the bridge device has an interrupt function enabled; the interrupt function includes MSI interrupt and MSI-X interrupt;

If the interrupt function is enabled on the bridge device, the register of the bridge device is further read to determine whether the bridge device supports hot swapping;

If the bridge device does not enable the interrupt function, the bridge device does not support hot plugging.

Optionally, the PCIe device control apparatus 200 further includes a device identifier allocation module configured to add the identification of the slot to the data structure corresponding to the bridge device. symbol variable;

Get an identifier and store the identifier into the variable.

In one embodiment, the program or code statement that allocates identifiers and stores corresponding identification data is encapsulated as a device identifier allocation module, so that it can be directly called whenever an identifier needs to be allocated. When assigning an identifier to a slot or device, the device identifier allocation module can be called during the scanning process of the PCIe device to pre-allocate an identifier for the slot; it can also be called through the device driver when initializing the terminal device. The device identifier assignment module assigns identifiers to the slots in which the terminal devices are located. After the device identifier allocation module allocates the identifier, the identifier data is stored in the corresponding data structure.

Optionally, the PCIe device control apparatus 200 further includes a device identifier acquisition module, and the device identifier acquisition module is configured to acquire a bridge device connected to the slot;

Read the variable storing the identifier of the slot from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable;

An identifier of the slot is assigned to the terminal device.

In one embodiment, the program or code statement that reads the identifier of the slot from the relevant data structure is encapsulated as a device identifier acquisition module, so that it can be directly called whenever it is necessary to obtain the identifier of the slot. When the slot identifier needs to be read from the data structure, the device identifier acquisition module is called to read it.

Figure 3 is a flow chart of PCIe device initialization proposed by an embodiment of the present application. As shown in Figure 3, in one embodiment, the initialization steps for the terminal device are as follows:

S1: When the system starts, perform system initialization;

S2: Initialize the PCIe structure in the system;

S3: Scan devices in the system;

S4: During the process of scanning the device, pre-allocate resources to the bridge device that supports hot-swapping, and call the device identifier allocation module to pre-allocate a unique identifier for the slot;

S5: When a terminal device is scanned, call the device identifier acquisition module in the device driver to obtain the identifier of the slot where the terminal device is located, and assign the identifier to the terminal device to complete subsequent initialization of the terminal device.

Optionally, the PCIe device control device 200 also includes:

The system initialization module is configured to initialize the system configuration when the system starts;

The PCIe initialization module is configured to initialize the data structure of the PCIe device and generate a data structure used to describe the PCIe device information; the data structure describing the PCIe device information includes: the bus to which the device belongs, the device type and the device ID; the describing PCIe The data structure of device information is a tree structure;

The device scanning module 201 is also configured to scan the devices in the system and determine the type of the currently scanned device; the device is a bridge device or a terminal device, and any terminal device is connected to a bridge device one-to-one. .

Optionally, the PCIe device control device 200 also includes:

The resource configuration module is configured to allocate corresponding device resources to the currently scanned terminal device; the device resources include bus resources and memory resources;

The driver matching module is configured to call the bus detection interface to match the corresponding device driver for the terminal device.

Optionally, the resource configuration module is further configured to reserve resources to be allocated for the bridge device when the bridge device supports hot plugging; the resources to be allocated include bus resources and memory resources.

Optionally, the device scanning module 201 is also configured to return and continue scanning other devices in the system when the bridge device does not support hot plugging.

Optionally, the PCIe device control device 200 also includes a hot plug processing module configured to create an event processing callback function when the bridge device supports hot plug, and according to the hot plug of the terminal device in the system Behavior, perform add or delete operations.

Optionally, the hot-plug processing module is also configured to obtain interrupt information through the event processing callback function and determine the interrupt type;

If the interrupt type is device addition, rescan the devices in the system and initialize the newly added terminal device in the device driver;

If the interrupt type is device deletion, call the delete operation function to stop the corresponding terminal device, delete the corresponding data in the data structure corresponding to the bridge device connected to the terminal device, and release device resources; the device resources include a bus resources and memory resources.

Optionally, the hot-swap processing module is also configured to create an interrupt callback function;

Create an interrupt work queue with the event processing callback function through the interrupt callback function.

Regarding the devices in the above embodiments, the specific manner in which each module performs operations has been described in detail in the embodiments related to the method, and will not be described in detail here.

The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the present application. within the scope of protection.

For the method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that this application is not limited by the described action sequence, because according to this application, some steps Other orders or simultaneous steps are possible. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and components involved are not necessarily necessary for this application.

Those skilled in the art should understand that embodiments of the present application may be provided as methods, devices, or computer program products. Therefore, embodiments of the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, embodiments of the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

Embodiments of the present application are described with reference to flowcharts and/or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the present application. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine such that the instructions are executed by the processor of the computer or other programmable data processing terminal device. Means are generated for implementing the functions specified in the process or processes of the flowchart diagrams and/or the block or blocks of the block diagrams.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing terminal equipment to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the The instruction means implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, so that a series of operating steps are performed on the computer or other programmable terminal equipment to produce computer-implemented processing, thereby causing the computer or other programmable terminal equipment to perform a computer-implemented process. The instructions executed on provide steps for implementing the functions specified in a process or processes of the flow diagrams and/or a block or blocks of the block diagrams.

Although preferred embodiments of the embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once the basic inventive concepts are understood. Therefore, the appended claims are intended to be construed to include the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

Finally, it should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or any such actual relationship or sequence between operations. Furthermore, the terms "comprises," "comprises," or any other variation thereof are intended to cover a non-exclusive inclusion such that a process, method, article, or end device that includes a list of elements includes not only those elements, but also elements not expressly listed or other elements inherent to such process, method, article or terminal equipment. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article or terminal device including the stated element.

The PCIe device control method and device provided by this application have been introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and implementation of this application. Its core idea; at the same time, for those of ordinary skill in the field, there will be changes in the specific implementation and application scope based on the ideas of this application. In summary, the content of this specification should not be understood as an infringement of this application. limit.

Claims (11)

1. A PCIe device control method, characterized by comprising: When a bridge device is scanned from the system, determine whether the bridge device supports hot plugging; When the bridge device supports hot plugging, assign an identifier to the slot connected to the bridge device; the identifier is a unique identifier; The identifier of the slot is assigned to the terminal device in the slot, and the terminal device is initialized through the device driver. 2. The PCIe device control method according to claim 1, characterized in that when a bridge device is scanned from the system, determining whether the bridge device supports hot plugging includes: Query whether the bridge device has enabled the interrupt function; the interrupt function includes MSI interrupt and MSI-X interrupt; If the interrupt function is enabled on the bridge device, the register of the bridge device is further read to determine whether the bridge device supports hot swapping; If the interrupt function is not enabled on the bridge device, the bridge device does not support hot plugging. 3. The PCIe device control method according to claim 1, characterized in that allocating an identifier to a slot connected to the bridge device includes: Add a variable for storing the identifier of the slot to the data structure corresponding to the bridge device; Get an identifier and store the identifier into the variable. 4. The PCIe device control method according to claim 3, wherein allocating the identifier of the slot to the terminal device in the slot includes: In the device driver, perform an operation of obtaining the bridge device connected to the slot; Read the variable storing the identifier of the slot from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable; An identifier of the slot is assigned to the terminal device. 5. The PCIe device control method according to claim 1, wherein allocating an identifier to a slot connected to the bridge device includes: In the device driver, perform an operation of adding a variable used to save the identifier of the slot to the data structure corresponding to the bridge device; Get an identifier and store the identifier into the variable. 6. The PCIe device control method according to claim 5, characterized in that allocating the identifier of the slot to the terminal device in the slot includes: In the device driver, perform an operation of obtaining the bridge device connected to the slot; Read the variable storing the identifier of the slot from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable; An identifier of the slot is assigned to the terminal device. 7. The PCIe device control method according to claim 1, further comprising: When the system starts, initialize the system configuration; Initialize the data structure of the PCIe device and generate a data structure used to describe the PCIe device information; the data structure describing the PCIe device information includes: the bus to which the device belongs, device type and device ID; the data structure describing the PCIe device information is a tree like structure; Scan the devices in the system and determine the type of the currently scanned device; the device is a bridge device or a terminal device, and any terminal device is connected to a bridge device one-to-one. 8. The PCIe device control method according to claim 1, further comprising: Allocate corresponding device resources to the currently scanned terminal device; the device resources include bus resources and memory resources; Call the bus detection interface to match the corresponding device driver for the terminal device. 9. The PCIe device control method according to claim 1, further comprising: When the bridge device supports hot plugging, resources to be allocated are reserved for the bridge device; the resources to be allocated include bus resources and memory resources; When the bridge device does not support hot plugging, return and continue scanning other devices in the system. 10. The PCIe device control method according to claim 1, further comprising: When the bridge device supports hot plugging, create an interrupt callback function, and create an interrupt work queue and event processing callback function through the interrupt callback function; The event processing callback function performs add or delete operations based on the hot plug behavior of the terminal device in the system, including: Obtain interrupt information through the event processing callback function and determine the interrupt type; If the interrupt type is device addition, rescan the devices in the system, and when the newly added terminal device is scanned, call the device driver; Execute in the device driver the operation of obtaining the bridge device connected to the slot where the newly added terminal device is located; Read the variable holding the identifier of the slot where the newly added terminal device is located from the data structure corresponding to the bridge device, and obtain the identifier of the slot from the variable; Assign the identifier of the slot to the newly added terminal device; Initialize the newly added terminal device in the device driver; If the interruption type is device deletion, call the delete operation function to stop the corresponding terminal device, delete the corresponding data in the data structure corresponding to the bridge device connected to the terminal device, and release the device resources allocated to the terminal device. ; The device resources include bus resources and memory resources. 11. A PCIe device control device, characterized in that it is used to perform the method according to any one of claims 1-10, including: A device scanning module configured to determine whether the bridge device supports hot swap when a bridge device is scanned from the system; An identifier allocation module configured to allocate an identifier to a slot connected to the bridge device when the bridge device supports hot plugging; The device initialization module is configured to allocate the identifier of the slot to the terminal device in the slot, and initialize the terminal device through a device driver.