Modules

Cache
[Caching]

Modules

 Object
 Cache Implementation

Access Functions



int nl_cache_nitems (struct nl_cache *cache)
 Return the number of items in the cache.
int nl_cache_nitems_filter (struct nl_cache *cache, struct nl_object *filter)
 Return the number of items matching a filter in the cache.
int nl_cache_is_empty (struct nl_cache *cache)
 Returns true if the cache is empty.
struct nl_cache_opsnl_cache_get_ops (struct nl_cache *cache)
 Return the operations set of the cache.
struct nl_object * nl_cache_get_first (struct nl_cache *cache)
 Return the first element in the cache.
struct nl_object * nl_cache_get_last (struct nl_cache *cache)
 Return the last element in the cache.
struct nl_object * nl_cache_get_next (struct nl_object *obj)
 Return the next element in the cache.
struct nl_object * nl_cache_get_prev (struct nl_object *obj)
 Return the previous element in the cache.

Cache Creation/Deletion



struct nl_cache * nl_cache_alloc (struct nl_cache_ops *ops)
 Allocate an empty cache.
struct nl_cache * nl_cache_alloc_name (const char *kind)
 Allocate an empty cache based on type name.
struct nl_cache * nl_cache_subset (struct nl_cache *orig, struct nl_object *filter)
 Allocate a new cache containing a subset of a cache.
void nl_cache_clear (struct nl_cache *cache)
 Clear a cache.
void nl_cache_free (struct nl_cache *cache)
 Free a cache.

Cache Modifications



int nl_cache_add (struct nl_cache *cache, struct nl_object *obj)
 Add object to a cache.
int nl_cache_move (struct nl_cache *cache, struct nl_object *obj)
 Move object from one cache to another.
void nl_cache_remove (struct nl_object *obj)
 Removes an object from a cache.
struct nl_object * nl_cache_search (struct nl_cache *cache, struct nl_object *needle)
 Search for an object in a cache.

Synchronization



int nl_cache_request_full_dump (struct nl_handle *handle, struct nl_cache *cache)
 Request a full dump from the kernel to fill a cache.
int __cache_pickup (struct nl_handle *handle, struct nl_cache *cache, struct nl_parser_param *param)
int nl_cache_pickup (struct nl_handle *handle, struct nl_cache *cache)
 Pickup a netlink dump response and put it into a cache.
int nl_cache_include (struct nl_cache *cache, struct nl_object *obj, change_func_t change_cb)
int nl_cache_resync (struct nl_handle *handle, struct nl_cache *cache, change_func_t change_cb)

Parsing



int nl_cache_parse_and_add (struct nl_cache *cache, struct nl_msg *msg)
 Parse a netlink message and add it to the cache.
int nl_cache_refill (struct nl_handle *handle, struct nl_cache *cache)
 (Re)fill a cache with the contents in the kernel.

Utillities



void nl_cache_mark_all (struct nl_cache *cache)
 Mark all objects in a cache.

Dumping



void nl_cache_dump (struct nl_cache *cache, struct nl_dump_params *params)
 Dump all elements of a cache.
void nl_cache_dump_filter (struct nl_cache *cache, struct nl_dump_params *params, struct nl_object *filter)
 Dump all elements of a cache (filtered).

Iterators



void nl_cache_foreach (struct nl_cache *cache, void(*cb)(struct nl_object *, void *), void *arg)
 Call a callback on each element of the cache.
void nl_cache_foreach_filter (struct nl_cache *cache, struct nl_object *filter, void(*cb)(struct nl_object *, void *), void *arg)
 Call a callback on each element of the cache (filtered).

Detailed Description

   Cache Management             |    | Type Specific Cache Operations
                                      
                                |    | +----------------+ +------------+
                                       | request update | | msg_parser |
                                |    | +----------------+ +------------+
                                     +- - - - -^- - - - - - - -^- -|- - - -
    nl_cache_update:            |              |               |   |
          1) --------- co_request_update ------+               |   |
                                |                              |   |
          2) destroy old cache     +----------- pp_cb ---------|---+
                                |  |                           |
          3) ---------- nl_recvmsgs ----------+   +- cb_valid -+
             +--------------+   |  |          |   |
             | nl_cache_add |<-----+   + - - -v- -|- - - - - - - - - - -
             +--------------+   |      | +-------------+
                                         | nl_recvmsgs |
                                |      | +-----|-^-----+
                                           +---v-|---+
                                |      |   | nl_recv |
                                           +---------+
                                |      |                 Core Netlink

Function Documentation

int nl_cache_nitems ( struct nl_cache *  cache  ) 
Parameters:
cache cache handle

Definition at line 58 of file cache.c.

int nl_cache_nitems_filter ( struct nl_cache *  cache,
struct nl_object *  filter 
)
Parameters:
cache Cache object.
filter Filter object.

Definition at line 68 of file cache.c.

References nl_object_match_filter().

int nl_cache_is_empty ( struct nl_cache *  cache  ) 
Parameters:
cache Cache to check
Returns:
true if the cache is empty, otherwise false is returned.

Definition at line 94 of file cache.c.

struct nl_cache_ops* nl_cache_get_ops ( struct nl_cache *  cache  )  [read]
Parameters:
cache cache handle

Definition at line 103 of file cache.c.

struct nl_object* nl_cache_get_first ( struct nl_cache *  cache  )  [read]
Parameters:
cache cache handle

Definition at line 112 of file cache.c.

struct nl_object* nl_cache_get_last ( struct nl_cache *  cache  )  [read]
Parameters:
cache cache handle

Definition at line 125 of file cache.c.

struct nl_object* nl_cache_get_next ( struct nl_object *  obj  )  [read]
Parameters:
obj current object

Definition at line 138 of file cache.c.

struct nl_object* nl_cache_get_prev ( struct nl_object *  obj  )  [read]
Parameters:
obj current object

Definition at line 151 of file cache.c.

struct nl_cache* nl_cache_alloc ( struct nl_cache_ops ops  )  [read]
struct nl_cache* nl_cache_alloc_name ( const char *  kind  )  [read]
Parameters:
kind Name of cache type
Returns:
A newly allocated and initialized cache.

Definition at line 196 of file cache.c.

References nl_cache_alloc(), and nl_cache_ops_lookup().

struct nl_cache* nl_cache_subset ( struct nl_cache *  orig,
struct nl_object *  filter 
) [read]
Parameters:
orig Original cache to be based on
filter Filter defining the subset to be filled into new cache
Returns:
A newly allocated cache or NULL.

Definition at line 215 of file cache.c.

References nl_cache_add(), nl_cache_alloc(), and nl_object_match_filter().

void nl_cache_clear ( struct nl_cache *  cache  ) 
Parameters:
cache cache to clear

Removes all elements of a cache.

Definition at line 247 of file cache.c.

References nl_cache_remove().

Referenced by nl_cache_free(), and nl_cache_refill().

void nl_cache_free ( struct nl_cache *  cache  ) 
Parameters:
cache Cache to free.

Removes all elements of a cache and frees all memory.

Note:
Use this function if you are working with allocated caches.

Definition at line 265 of file cache.c.

References nl_cache_clear().

Referenced by genl_ctrl_resolve(), nl_cache_mngr_add(), rtnl_class_alloc_cache(), rtnl_cls_alloc_cache(), rtnl_link_alloc_cache(), rtnl_neigh_alloc_cache(), rtnl_neightbl_alloc_cache(), and rtnl_qdisc_alloc_cache().

int nl_cache_add ( struct nl_cache *  cache,
struct nl_object *  obj 
)
Parameters:
cache Cache to add object to
obj Object to be added to the cache

Adds the given object to the specified cache. The object is cloned if it has been added to another cache already.

Returns:
0 or a negative error code.

Definition at line 302 of file cache.c.

References nl_object_clone(), and nl_object_get().

Referenced by nl_cache_subset().

int nl_cache_move ( struct nl_cache *  cache,
struct nl_object *  obj 
)
Parameters:
cache Cache to move object to.
obj Object subject to be moved

Removes the given object from its associated cache if needed and adds it to the new cache.

Returns:
0 on success or a negative error code.

Definition at line 331 of file cache.c.

References nl_cache_remove(), and nl_object_get().

void nl_cache_remove ( struct nl_object *  obj  ) 
Parameters:
obj Object to remove from its cache

Removes the object obj from the cache it is assigned to, since an object can only be assigned to one cache at a time, the cache must ne be passed along with it.

Definition at line 356 of file cache.c.

References nl_object_put().

Referenced by nl_cache_clear(), nl_cache_move(), and nl_object_free().

struct nl_object* nl_cache_search ( struct nl_cache *  cache,
struct nl_object *  needle 
) [read]
Parameters:
cache Cache to search in.
needle Object to look for.

Iterates over the cache and looks for an object with identical identifiers as the needle.

Returns:
Reference to object or NULL if not found.
Note:
The returned object must be returned via nl_object_put().

Definition at line 383 of file cache.c.

References nl_object_get(), and nl_object_identical().

int nl_cache_request_full_dump ( struct nl_handle *  handle,
struct nl_cache *  cache 
)
Parameters:
handle Netlink handle
cache Cache subjected to be filled.

Send a dumping request to the kernel causing it to dump all objects related to the specified cache to the netlink socket.

Use nl_cache_pickup() to read the objects from the socket and fill them into a cache.

Definition at line 417 of file cache.c.

Referenced by nl_cache_refill().

int nl_cache_pickup ( struct nl_handle *  handle,
struct nl_cache *  cache 
)
Parameters:
handle Netlink handle.
cache Cache to put items into.

Waits for netlink messages to arrive, parses them and puts them into the specified cache.

Returns:
0 on success or a negative error code.

Definition at line 487 of file cache.c.

Referenced by flnl_lookup(), and nl_cache_refill().

int nl_cache_parse_and_add ( struct nl_cache *  cache,
struct nl_msg *  msg 
)
Parameters:
cache cache to add element to
msg netlink message

Parses a netlink message by calling the cache specific message parser and adds the new element to the cache.

Returns:
0 or a negative error code.

Definition at line 642 of file cache.c.

References nlmsg_hdr().

int nl_cache_refill ( struct nl_handle *  handle,
struct nl_cache *  cache 
)
Parameters:
handle netlink handle
cache cache to update

Clears the specified cache and fills it with the current state in the kernel.

Returns:
0 or a negative error code.

Definition at line 662 of file cache.c.

References nl_cache_clear(), nl_cache_pickup(), and nl_cache_request_full_dump().

Referenced by nfnl_ct_alloc_cache(), nl_cache_mngr_add(), rtnl_class_alloc_cache(), rtnl_cls_alloc_cache(), rtnl_link_alloc_cache(), rtnl_neigh_alloc_cache(), rtnl_neightbl_alloc_cache(), rtnl_qdisc_alloc_cache(), rtnl_route_alloc_cache(), and rtnl_rule_alloc_cache_by_family().

void nl_cache_mark_all ( struct nl_cache *  cache  ) 
Parameters:
cache Cache to mark all objects in

Definition at line 688 of file cache.c.

References nl_object_mark().

void nl_cache_dump ( struct nl_cache *  cache,
struct nl_dump_params params 
)
Parameters:
cache cache to dump
params dumping parameters

Dumps all elements of the cache to the file descriptor fd.

Definition at line 713 of file cache.c.

References nl_cache_dump_filter().

void nl_cache_dump_filter ( struct nl_cache *  cache,
struct nl_dump_params params,
struct nl_object *  filter 
)
Parameters:
cache cache to dump
params dumping parameters (optional)
filter filter object

Dumps all elements of the cache to the file descriptor fd given they match the given filter filter.

Definition at line 727 of file cache.c.

References nl_dump_params::dp_type, nl_object_match_filter(), and nl_object_ops::oo_dump.

Referenced by nl_cache_dump().

void nl_cache_foreach ( struct nl_cache *  cache,
void(*)(struct nl_object *, void *)  cb,
void *  arg 
)
Parameters:
cache cache to iterate on
cb callback function
arg argument passed to callback function

Calls a callback function cb on each element of the cache. The argument arg is passed on the callback function.

Definition at line 773 of file cache.c.

References nl_cache_foreach_filter().

void nl_cache_foreach_filter ( struct nl_cache *  cache,
struct nl_object *  filter,
void(*)(struct nl_object *, void *)  cb,
void *  arg 
)
Parameters:
cache cache to iterate on
filter filter object
cb callback function
arg argument passed to callback function

Calls a callback function cb on each element of the cache that matches the filter. The argument arg is passed on to the callback function.

Definition at line 790 of file cache.c.

References nl_object_match_filter().

Referenced by nl_cache_foreach(), rtnl_class_foreach_child(), rtnl_class_foreach_cls(), rtnl_qdisc_foreach_child(), and rtnl_qdisc_foreach_cls().