Understanding Linux Network Internals

Functions and Variables Featured in This Chapter

Table 5-1 summarizes the functions, macros, variables, and data structures introduced in this chapter.

Table 5-1. Functions, macros, variables, and data structures related to system initialization

Name	Description
Functions and macros
request_irq free_irq	Registers and releases, respectively, a callback handler for an IRQ line. The registration can be exclusive or shared.
request_region release_region	Allocates and releases I/O ports and I/O memory.
call_usermodehelper	Invokes a user-space helper application.
module_param	Macro used to define configuration parameters for modules.
net_dev_init	Initializes a piece of the networking code at boot time.
Global variables
dev_boot_phase	Boolean flag used by legacy code to enforce the execution of net_dev_init before NIC device drivers register themselves.
irq_desc	Pointer to the vector of IRQ descriptors.
Data structure
struct irq_action	Each IRQ line is defined by an instance of this structure. Among other fields, it includes a callback function.
net_device	Describes a network device.