Section 36.6.  Functions and Variables Featured in This Part of the Book

36.6. Functions and Variables Featured in This Part of the Book Table 36-13 summarizes the main functions, variables, and data structures introduced or referenced in the chapters of this book covering the routing subsystem. You can find more in the section "Generic Helper Routines and Macros" and "Helper Routines" in Chapter 32, and the two "Helper Routines", in Chapter 35. Table 36-13. Functions, variables, and data structures in the routing subsystem Functions   for_ifa, endfor_ifa for_primary_ifa, endfor_ifa Macros used to browse the IPv4 addresses configured on a network device. See the section "Primary and Secondary IP Addresses" in Chapter 32. FIB_RES_XXX Set of macros used to access the fields of the fib_result structure. See the section "Generic Helper Routines and Macros" in Chapter 32. LOOPBACK ZERONET MULTICAST LOCAL_MCAST/BADCLASS Macros used to recognize special IP addresses. See the section "Generic Helper Routines and Macros" in Chapter 32. fib_hash_lock fib_info_lock fib_rules_lock rt_flush_lock fib_multipath_lock alg_table_lock Locks used to protect various pieces of data. See the section "Global Locks" in Chapter 32. ip_rt_init ip_fib_init devinet_init fib_rules_init fib_hash_init dst_init Initialization routines. See the section "Routing Subsystem Initialization" in Chapter 32. dst_alloc Allocate an entry for the routing cache. See the section "Cache Entry Allocation and Reference Counts" in Chapter 33. rt_periodic_timer rt_secret_timer Timers. See the sections "Garbage Collection" and "Flushing the Routing Cache" in Chapter 33. fib_netdev_event fib_inetaddr_event Handlers for the netdev_chain and inetaddr_chain notification chains. See the section "External Events" in Chapter 32. fib_add_ifaddr fib_del_ifaddr Used to update the routing table upon the addition or removal of an IP address from the configuration of a local network device. See the sections "Adding an IP address" and "Removing an IP address" in Chapter 32. fib_magic Used by the kernel to insert routes under specific conditions. See the section "Routes Inserted by the Kernel: The fib_magic Function." fib_rules_detach fib_rules_attach Enables and disables routing policies when network devices are registered and unregistered, respectively. See the section "Impacts on the policy database" in Chapter 32. rtmsg_fib Used to send notification on a specific Netlink multicast group when routes are added or removed. See the section "Netlink Notifications" in Chapter 32. ip_route_input _ _ip_route_output_key ip_route_output_flow ip_route_output_key ip_route_connect ip_route_newports The first two functions are routing cache lookup routines, and the others are wrappers around them. See the section "Cache Lookup" in Chapter 33. ip_route_input_slow ip_route_output_slow Routing table lookup routines. See Chapter 35. ip_route_input_mc Lookup routines used for multicast destinations. ip_mkroute_input ip_mkroute_input_def ip_mkroute_output ip_mkroute_output_def fib_select_default fib_select_multipath Various support routines used by ip_route_input_slow and ip_route_output_slow. See Chapter 35. fib_lookup fn_hash_lookup fib_semantic_match Routines called at different stages during a routing table lookup. See the section "High-Level View of Lookup Functions" in Chapter 35. fn_hash_insert Add a new route to a routing table. See the section "Adding a Route" in Chapter 34. fn_hash_delete Remove a route from a routing table. See the section "Deleting a Route" in Chapter 34. rt_intern_hash Add an entry to the routing cache. See the section "Adding Elements to the Cache" in Chapter 33. multipath_alg_register multipath_alg_unregister Register and unregister a multipath caching algorithm. See the section "Registering a Caching Algorithm" in Chapter 33. multipath_select_route multipath_flush multipath_set_nhinfo multipath_remove Various routines used to manage cache entries associated with multipath routes. See the section "Interface Between the Routing Cache and Multipath" in Chapter 33. More routines are listed in the section "Helper Routines" in the same chapter. rt_free dst_free Free an rtable and a dst_entry structure, respectively. rt_garbage_collect rt_may_expire Garbage collection routines used for the routing cache. See the section "rt_garbage_collect Function" in Chapter 33. dst_input dst_output Complete the reception and transmission of a packet, respectively. See the section "Cache Lookup" in Chapter 33. See also the section "Setting Functions for Reception and Transmission" in Chapter 35. rt_garbage_collect dst_destroy dst_ifdown dst_negative_advice dst_link_failure dst_set_expires Routines used for the initialization of the dst_ops instance associated with the IPv4 protocol. See the section "Interface Between the DST and Calling Protocols" in Chapter 33. dst_dev_event Handler used by the DST subsystem to process notifications from the neTDev_chain notification chain. See the section "External Events" in Chapter 32. RT_CACHE_STAT_INC Update per-CPU statistics. See the section "Statistics." Variables   ip_fib_local_table ip_fib_main_table Routing tables. See the section "The Two Default Routing Tables: ip_fib_main_table and ip_fib_local_table" in Chapter 34. rt_hash_table Routing cache. See Chapter 33. rt_hash_mask Size of the routing cache (i.e., number of buckets of the hash table). dst_garbage_list List of dst_entry instances that cannot be removed because they are still referenced. See Chapter 33. fib_tables List of fib_table instances. See Figure 34-1 in Chapter 34. fib_rules List of routing policies. See the section "fib_lookup with Policy Routing" in Chapter 35. fib_info_cnt Number of outstanding fib_info instances. See the section "Dynamic resizing of global hash tables" in Chapter 34. fib_info_hash fib_info_laddrhash Hash tables used to search fib_info instances. See the section "Organization of fib_info Structures" in Chapter 34. fib_info_devhash Hash table used to search fib_nh instances. See the section "Organization of Next-Hop Router Structures" in Chapter 34. fib_props Vector whose elements are used by the lookup routine fib_semantic_match to map route types to return values. See the section "Return value from fib_semantic_match" in Chapter 35. Data structures   fib_table structure fn_zone structure fib_node structure fib_alias structure fib_info structure fib_nh structure fib_rule structure rtable structure dst_entry structure dst_ops structure flowi structure rt_cache_stat structure ip_mp_alg_ops structure Key data structures used by the routing code. They are described in detail in the section "Data Structures Featured in This Part of the Book."