2
* lib/route/qdisc.c Queueing Disciplines
4
* This library is free software; you can redistribute it and/or
5
* modify it under the terms of the GNU Lesser General Public
6
* License as published by the Free Software Foundation version 2.1
9
* Copyright (c) 2003-2011 Thomas Graf <tgraf@suug.ch>
14
* @defgroup qdisc Queueing Disciplines
17
* In general, qdiscs are identified by the major part of a traffic control
18
* handle (the upper 16 bits). A few special values exist though:
19
* - \c TC_H_ROOT: root qdisc (directly attached to the device)
20
* - \c TC_H_INGRESS: ingress qdisc (directly attached to the device)
21
* - \c TC_H_UNSPEC: unspecified qdisc (no reference)
23
* @par 1) Adding a Qdisc
25
* // Allocate a new empty qdisc to be filled out
26
* struct rtnl_qdisc *qdisc = rtnl_qdisc_alloc();
28
* // ... specify the kind of the Qdisc
29
* rtnl_qdisc_set_kind(qdisc, "pfifo");
31
* // Specify the device the qdisc should be attached to
32
* rtnl_qdisc_set_ifindex(qdisc, ifindex);
34
* // ... specify the parent qdisc
35
* rtnl_qdisc_set_parent(qdisc, TC_H_ROOT);
37
* // Specifying the handle is not required but makes reidentifying easier
38
* // and may help to avoid adding a qdisc twice.
39
* rtnl_qdisc_set_handle(qdisc, 0x000A0000);
41
* // Now on to specify the qdisc specific options, see the relevant qdisc
42
* // modules for documentation, in this example we set the upper limit of
43
* // the packet fifo qdisc to 64
44
* rtnl_qdisc_fifo_set_limit(qdisc, 64);
46
* rtnl_qdisc_add(handle, qdisc, NLM_R_REPLACE);
48
* // Free up the memory
49
* rtnl_qdisc_put(qdisc);
52
* @par 2) Deleting a Qdisc
54
* // Allocate a new empty qdisc to be filled out with the parameters
55
* // specifying the qdisc to be deleted. Alternatively a fully equiped
56
* // Qdisc object from a cache can be used.
57
* struct rtnl_qdisc *qdisc = rtnl_qdisc_alloc();
59
* // The interface index of the device the qdisc is on and the parent handle
60
* // are the least required fields to be filled out.
61
* // Note: Specify TC_H_ROOT or TC_H_INGRESS as parent handle to delete the
62
* // root respectively root ingress qdisc.
63
* rtnl_qdisc_set_ifindex(qdisc, ifindex);
64
* rtnl_qdisc_set_parent(qdisc, parent_handle);
66
* // If required for identification, the handle can be specified as well.
67
* rtnl_qdisc_set_handle(qdisc, qdisc_handle);
69
* // Not required but maybe helpful as sanity check, the kind of the qdisc
70
* // can be specified to avoid mistakes.
71
* rtnl_qdisc_set_kind(qdisc, "pfifo");
73
* // Finally delete the qdisc with rtnl_qdisc_delete(), alternatively
74
* // rtnl_qdisc_build_delete_request() can be invoked to generate an
75
* // appropritate netlink message to send out.
76
* rtnl_qdisc_delete(handle, qdisc);
78
* // Free up the memory
79
* rtnl_qdisc_put(qdisc);
85
#include <netlink-local.h>
86
#include <netlink-tc.h>
87
#include <netlink/netlink.h>
88
#include <netlink/utils.h>
89
#include <netlink/route/link.h>
90
#include <netlink/route/tc-api.h>
91
#include <netlink/route/qdisc.h>
92
#include <netlink/route/class.h>
93
#include <netlink/route/classifier.h>
95
static struct nl_cache_ops rtnl_qdisc_ops;
97
static int qdisc_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
98
struct nlmsghdr *n, struct nl_parser_param *pp)
100
struct rtnl_qdisc *qdisc;
103
if (!(qdisc = rtnl_qdisc_alloc()))
106
if ((err = rtnl_tc_msg_parse(n, TC_CAST(qdisc))) < 0)
109
err = pp->pp_cb(OBJ_CAST(qdisc), pp);
111
rtnl_qdisc_put(qdisc);
116
static int qdisc_request_update(struct nl_cache *c, struct nl_sock *sk)
118
struct tcmsg tchdr = {
119
.tcm_family = AF_UNSPEC,
120
.tcm_ifindex = c->c_iarg1,
123
return nl_send_simple(sk, RTM_GETQDISC, NLM_F_DUMP, &tchdr,
128
* @name QDisc Addition
132
static int qdisc_build(struct rtnl_qdisc *qdisc, int type, int flags,
133
struct nl_msg **result)
135
return rtnl_tc_msg_build(TC_CAST(qdisc), type, flags, result);
138
/* Some qdiscs don't accept properly nested messages (e.g. netem). To
139
* accomodate for this, they can complete the message themselves.
141
else if (qops && qops->qo_build_msg) {
142
err = qops->qo_build_msg(qdisc, *result);
150
* Build a netlink message to add a new qdisc
151
* @arg qdisc qdisc to add
152
* @arg flags additional netlink message flags
153
* @arg result Pointer to store resulting message.
155
* Builds a new netlink message requesting an addition of a qdisc.
156
* The netlink message header isn't fully equipped with all relevant
157
* fields and must be sent out via nl_send_auto_complete() or
158
* supplemented as needed.
160
* Common message flags used:
161
* - NLM_F_REPLACE - replace a potential existing qdisc
163
* @return 0 on success or a negative error code.
165
int rtnl_qdisc_build_add_request(struct rtnl_qdisc *qdisc, int flags,
166
struct nl_msg **result)
168
return qdisc_build(qdisc, RTM_NEWQDISC, NLM_F_CREATE | flags, result);
173
* @arg sk Netlink socket.
174
* @arg qdisc qdisc to delete
175
* @arg flags additional netlink message flags
177
* Builds a netlink message by calling rtnl_qdisc_build_add_request(),
178
* sends the request to the kernel and waits for the ACK to be
179
* received and thus blocks until the request has been processed.
181
* Common message flags used:
182
* - NLM_F_REPLACE - replace a potential existing qdisc
184
* @return 0 on success or a negative error code
186
int rtnl_qdisc_add(struct nl_sock *sk, struct rtnl_qdisc *qdisc,
192
if ((err = rtnl_qdisc_build_add_request(qdisc, flags, &msg)) < 0)
195
err = nl_send_auto_complete(sk, msg);
200
return wait_for_ack(sk);
206
* @name QDisc Modification
211
* Build a netlink message to change attributes of a existing qdisc
212
* @arg qdisc qdisc to change
213
* @arg new new qdisc attributes
214
* @arg result Pointer to store resulting message.
216
* Builds a new netlink message requesting an change of qdisc
217
* attributes. The netlink message header isn't fully equipped
218
* with all relevant fields and must be sent out via
219
* nl_send_auto_complete() or supplemented as needed.
221
* @return 0 on success or a negative error code.
223
int rtnl_qdisc_build_change_request(struct rtnl_qdisc *qdisc,
224
struct rtnl_qdisc *new,
225
struct nl_msg **result)
227
return qdisc_build(qdisc, RTM_NEWQDISC, NLM_F_REPLACE, result);
231
* Change attributes of a qdisc
232
* @arg sk Netlink socket.
233
* @arg qdisc qdisc to change
234
* @arg new new qdisc attributes
236
* Builds a netlink message by calling rtnl_qdisc_build_change_request(),
237
* sends the request to the kernel and waits for the ACK to be
238
* received and thus blocks until the request has been processed.
240
* @return 0 on success or a negative error code
242
int rtnl_qdisc_change(struct nl_sock *sk, struct rtnl_qdisc *qdisc,
243
struct rtnl_qdisc *new)
248
if ((err = rtnl_qdisc_build_change_request(qdisc, new, &msg)) < 0)
251
err = nl_send_auto_complete(sk, msg);
256
return wait_for_ack(sk);
262
* @name QDisc Deletion
267
* Build a netlink request message to delete a qdisc
268
* @arg qdisc qdisc to delete
269
* @arg result Pointer to store resulting message.
271
* Builds a new netlink message requesting a deletion of a qdisc.
272
* The netlink message header isn't fully equipped with all relevant
273
* fields and must thus be sent out via nl_send_auto_complete()
274
* or supplemented as needed.
276
* @return 0 on success or a negative error code.
278
int rtnl_qdisc_build_delete_request(struct rtnl_qdisc *qdisc,
279
struct nl_msg **result)
283
int required = TCA_ATTR_IFINDEX | TCA_ATTR_PARENT;
285
if ((qdisc->ce_mask & required) != required)
288
msg = nlmsg_alloc_simple(RTM_DELQDISC, 0);
292
tchdr.tcm_family = AF_UNSPEC;
293
tchdr.tcm_handle = qdisc->q_handle;
294
tchdr.tcm_parent = qdisc->q_parent;
295
tchdr.tcm_ifindex = qdisc->q_ifindex;
296
if (nlmsg_append(msg, &tchdr, sizeof(tchdr), NLMSG_ALIGNTO) < 0) {
307
* @arg sk Netlink socket.
308
* @arg qdisc qdisc to delete
310
* Builds a netlink message by calling rtnl_qdisc_build_delete_request(),
311
* sends the request to the kernel and waits for the ACK to be
312
* received and thus blocks until the request has been processed.
314
* @return 0 on success or a negative error code
316
int rtnl_qdisc_delete(struct nl_sock *sk, struct rtnl_qdisc *qdisc)
321
if ((err = rtnl_qdisc_build_delete_request(qdisc, &msg)) < 0)
324
err = nl_send_auto_complete(sk, msg);
329
return wait_for_ack(sk);
335
* @name Qdisc Cache Management
340
* Build a qdisc cache including all qdiscs currently configured in
342
* @arg sk Netlink socket.
343
* @arg result Pointer to store resulting message.
345
* Allocates a new cache, initializes it properly and updates it to
346
* include all qdiscs currently configured in the kernel.
348
* @return 0 on success or a negative error code.
350
int rtnl_qdisc_alloc_cache(struct nl_sock *sk, struct nl_cache **result)
352
return nl_cache_alloc_and_fill(&rtnl_qdisc_ops, sk, result);
356
* Look up qdisc by its parent in the provided cache
357
* @arg cache qdisc cache
358
* @arg ifindex interface the qdisc is attached to
359
* @arg parent parent handle
360
* @return pointer to qdisc inside the cache or NULL if no match was found.
362
struct rtnl_qdisc * rtnl_qdisc_get_by_parent(struct nl_cache *cache,
363
int ifindex, uint32_t parent)
365
struct rtnl_qdisc *q;
367
if (cache->c_ops != &rtnl_qdisc_ops)
370
nl_list_for_each_entry(q, &cache->c_items, ce_list) {
371
if (q->q_parent == parent && q->q_ifindex == ifindex) {
372
nl_object_get((struct nl_object *) q);
381
* Look up qdisc by its handle in the provided cache
382
* @arg cache qdisc cache
383
* @arg ifindex interface the qdisc is attached to
384
* @arg handle qdisc handle
385
* @return pointer to qdisc inside the cache or NULL if no match was found.
387
struct rtnl_qdisc * rtnl_qdisc_get(struct nl_cache *cache,
388
int ifindex, uint32_t handle)
390
struct rtnl_qdisc *q;
392
if (cache->c_ops != &rtnl_qdisc_ops)
395
nl_list_for_each_entry(q, &cache->c_items, ce_list) {
396
if (q->q_handle == handle && q->q_ifindex == ifindex) {
397
nl_object_get((struct nl_object *) q);
408
* @name Allocation/Freeing
412
struct rtnl_qdisc *rtnl_qdisc_alloc(void)
416
tc = TC_CAST(nl_object_alloc(&qdisc_obj_ops));
418
tc->tc_type = RTNL_TC_TYPE_QDISC;
420
return (struct rtnl_qdisc *) tc;
423
void rtnl_qdisc_put(struct rtnl_qdisc *qdisc)
425
nl_object_put((struct nl_object *) qdisc);
436
* Call a callback for each child class of a qdisc
437
* @arg qdisc the parent qdisc
438
* @arg cache a class cache including all classes of the interface
439
* the specified qdisc is attached to
440
* @arg cb callback function
441
* @arg arg argument to be passed to callback function
443
void rtnl_qdisc_foreach_child(struct rtnl_qdisc *qdisc, struct nl_cache *cache,
444
void (*cb)(struct nl_object *, void *), void *arg)
446
struct rtnl_class *filter;
448
filter = rtnl_class_alloc();
452
rtnl_tc_set_parent(TC_CAST(filter), qdisc->q_handle);
453
rtnl_tc_set_ifindex(TC_CAST(filter), qdisc->q_ifindex);
454
rtnl_tc_set_kind(TC_CAST(filter), qdisc->q_kind);
456
nl_cache_foreach_filter(cache, OBJ_CAST(filter), cb, arg);
458
rtnl_class_put(filter);
462
* Call a callback for each filter attached to the qdisc
463
* @arg qdisc the parent qdisc
464
* @arg cache a filter cache including at least all the filters
465
* attached to the specified qdisc
466
* @arg cb callback function
467
* @arg arg argument to be passed to callback function
469
void rtnl_qdisc_foreach_cls(struct rtnl_qdisc *qdisc, struct nl_cache *cache,
470
void (*cb)(struct nl_object *, void *), void *arg)
472
struct rtnl_cls *filter;
474
filter = rtnl_cls_alloc();
478
rtnl_tc_set_ifindex((struct rtnl_tc *) filter, qdisc->q_ifindex);
479
rtnl_tc_set_parent((struct rtnl_tc *) filter, qdisc->q_parent);
481
nl_cache_foreach_filter(cache, (struct nl_object *) filter, cb, arg);
482
rtnl_cls_put(filter);
487
static void qdisc_dump_details(struct rtnl_tc *tc, struct nl_dump_params *p)
489
struct rtnl_qdisc *qdisc = (struct rtnl_qdisc *) tc;
491
nl_dump(p, "refcnt %u ", qdisc->q_info);
494
static struct rtnl_tc_type_ops qdisc_ops = {
495
.tt_type = RTNL_TC_TYPE_QDISC,
496
.tt_dump_prefix = "qdisc",
498
[NL_DUMP_DETAILS] = qdisc_dump_details,
502
static struct nl_cache_ops rtnl_qdisc_ops = {
503
.co_name = "route/qdisc",
504
.co_hdrsize = sizeof(struct tcmsg),
506
{ RTM_NEWQDISC, NL_ACT_NEW, "new" },
507
{ RTM_DELQDISC, NL_ACT_DEL, "del" },
508
{ RTM_GETQDISC, NL_ACT_GET, "get" },
509
END_OF_MSGTYPES_LIST,
511
.co_protocol = NETLINK_ROUTE,
512
.co_request_update = qdisc_request_update,
513
.co_msg_parser = qdisc_msg_parser,
514
.co_obj_ops = &qdisc_obj_ops,
517
struct nl_object_ops qdisc_obj_ops = {
518
.oo_name = "route/qdisc",
519
.oo_size = sizeof(struct rtnl_qdisc),
520
.oo_free_data = rtnl_tc_free_data,
521
.oo_clone = rtnl_tc_clone,
523
[NL_DUMP_LINE] = rtnl_tc_dump_line,
524
[NL_DUMP_DETAILS] = rtnl_tc_dump_details,
525
[NL_DUMP_STATS] = rtnl_tc_dump_stats,
527
.oo_compare = rtnl_tc_compare,
528
.oo_id_attrs = (TCA_ATTR_IFINDEX | TCA_ATTR_HANDLE),
531
static void __init qdisc_init(void)
533
rtnl_tc_type_register(&qdisc_ops);
534
nl_cache_mngt_register(&rtnl_qdisc_ops);
537
static void __exit qdisc_exit(void)
539
nl_cache_mngt_unregister(&rtnl_qdisc_ops);
540
rtnl_tc_type_unregister(&qdisc_ops);
added
removed
lib/route/qdisc.c
