Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
new file mode 100644
index 0000000..4323a74
--- /dev/null
+++ b/net/sched/sch_api.c
@@ -0,0 +1,1296 @@
+/*
+ * net/sched/sch_api.c Packet scheduler API.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ * Fixes:
+ *
+ * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired.
+ * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
+ * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/kmod.h>
+#include <linux/list.h>
+#include <linux/bitops.h>
+
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, u32 clid,
+ struct Qdisc *old, struct Qdisc *new);
+static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n,
+ struct Qdisc *q, unsigned long cl, int event);
+
+/*
+
+ Short review.
+ -------------
+
+ This file consists of two interrelated parts:
+
+ 1. queueing disciplines manager frontend.
+ 2. traffic classes manager frontend.
+
+ Generally, queueing discipline ("qdisc") is a black box,
+ which is able to enqueue packets and to dequeue them (when
+ device is ready to send something) in order and at times
+ determined by algorithm hidden in it.
+
+ qdisc's are divided to two categories:
+ - "queues", which have no internal structure visible from outside.
+ - "schedulers", which split all the packets to "traffic classes",
+ using "packet classifiers" (look at cls_api.c)
+
+ In turn, classes may have child qdiscs (as rule, queues)
+ attached to them etc. etc. etc.
+
+ The goal of the routines in this file is to translate
+ information supplied by user in the form of handles
+ to more intelligible for kernel form, to make some sanity
+ checks and part of work, which is common to all qdiscs
+ and to provide rtnetlink notifications.
+
+ All real intelligent work is done inside qdisc modules.
+
+
+
+ Every discipline has two major routines: enqueue and dequeue.
+
+ ---dequeue
+
+ dequeue usually returns a skb to send. It is allowed to return NULL,
+ but it does not mean that queue is empty, it just means that
+ discipline does not want to send anything this time.
+ Queue is really empty if q->q.qlen == 0.
+ For complicated disciplines with multiple queues q->q is not
+ real packet queue, but however q->q.qlen must be valid.
+
+ ---enqueue
+
+ enqueue returns 0, if packet was enqueued successfully.
+ If packet (this one or another one) was dropped, it returns
+ not zero error code.
+ NET_XMIT_DROP - this packet dropped
+ Expected action: do not backoff, but wait until queue will clear.
+ NET_XMIT_CN - probably this packet enqueued, but another one dropped.
+ Expected action: backoff or ignore
+ NET_XMIT_POLICED - dropped by police.
+ Expected action: backoff or error to real-time apps.
+
+ Auxiliary routines:
+
+ ---requeue
+
+ requeues once dequeued packet. It is used for non-standard or
+ just buggy devices, which can defer output even if dev->tbusy=0.
+
+ ---reset
+
+ returns qdisc to initial state: purge all buffers, clear all
+ timers, counters (except for statistics) etc.
+
+ ---init
+
+ initializes newly created qdisc.
+
+ ---destroy
+
+ destroys resources allocated by init and during lifetime of qdisc.
+
+ ---change
+
+ changes qdisc parameters.
+ */
+
+/* Protects list of registered TC modules. It is pure SMP lock. */
+static DEFINE_RWLOCK(qdisc_mod_lock);
+
+
+/************************************************
+ * Queueing disciplines manipulation. *
+ ************************************************/
+
+
+/* The list of all installed queueing disciplines. */
+
+static struct Qdisc_ops *qdisc_base;
+
+/* Register/uregister queueing discipline */
+
+int register_qdisc(struct Qdisc_ops *qops)
+{
+ struct Qdisc_ops *q, **qp;
+ int rc = -EEXIST;
+
+ write_lock(&qdisc_mod_lock);
+ for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
+ if (!strcmp(qops->id, q->id))
+ goto out;
+
+ if (qops->enqueue == NULL)
+ qops->enqueue = noop_qdisc_ops.enqueue;
+ if (qops->requeue == NULL)
+ qops->requeue = noop_qdisc_ops.requeue;
+ if (qops->dequeue == NULL)
+ qops->dequeue = noop_qdisc_ops.dequeue;
+
+ qops->next = NULL;
+ *qp = qops;
+ rc = 0;
+out:
+ write_unlock(&qdisc_mod_lock);
+ return rc;
+}
+
+int unregister_qdisc(struct Qdisc_ops *qops)
+{
+ struct Qdisc_ops *q, **qp;
+ int err = -ENOENT;
+
+ write_lock(&qdisc_mod_lock);
+ for (qp = &qdisc_base; (q=*qp)!=NULL; qp = &q->next)
+ if (q == qops)
+ break;
+ if (q) {
+ *qp = q->next;
+ q->next = NULL;
+ err = 0;
+ }
+ write_unlock(&qdisc_mod_lock);
+ return err;
+}
+
+/* We know handle. Find qdisc among all qdisc's attached to device
+ (root qdisc, all its children, children of children etc.)
+ */
+
+struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
+{
+ struct Qdisc *q;
+
+ read_lock_bh(&qdisc_tree_lock);
+ list_for_each_entry(q, &dev->qdisc_list, list) {
+ if (q->handle == handle) {
+ read_unlock_bh(&qdisc_tree_lock);
+ return q;
+ }
+ }
+ read_unlock_bh(&qdisc_tree_lock);
+ return NULL;
+}
+
+static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
+{
+ unsigned long cl;
+ struct Qdisc *leaf;
+ struct Qdisc_class_ops *cops = p->ops->cl_ops;
+
+ if (cops == NULL)
+ return NULL;
+ cl = cops->get(p, classid);
+
+ if (cl == 0)
+ return NULL;
+ leaf = cops->leaf(p, cl);
+ cops->put(p, cl);
+ return leaf;
+}
+
+/* Find queueing discipline by name */
+
+static struct Qdisc_ops *qdisc_lookup_ops(struct rtattr *kind)
+{
+ struct Qdisc_ops *q = NULL;
+
+ if (kind) {
+ read_lock(&qdisc_mod_lock);
+ for (q = qdisc_base; q; q = q->next) {
+ if (rtattr_strcmp(kind, q->id) == 0) {
+ if (!try_module_get(q->owner))
+ q = NULL;
+ break;
+ }
+ }
+ read_unlock(&qdisc_mod_lock);
+ }
+ return q;
+}
+
+static struct qdisc_rate_table *qdisc_rtab_list;
+
+struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct rtattr *tab)
+{
+ struct qdisc_rate_table *rtab;
+
+ for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
+ if (memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) == 0) {
+ rtab->refcnt++;
+ return rtab;
+ }
+ }
+
+ if (tab == NULL || r->rate == 0 || r->cell_log == 0 || RTA_PAYLOAD(tab) != 1024)
+ return NULL;
+
+ rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
+ if (rtab) {
+ rtab->rate = *r;
+ rtab->refcnt = 1;
+ memcpy(rtab->data, RTA_DATA(tab), 1024);
+ rtab->next = qdisc_rtab_list;
+ qdisc_rtab_list = rtab;
+ }
+ return rtab;
+}
+
+void qdisc_put_rtab(struct qdisc_rate_table *tab)
+{
+ struct qdisc_rate_table *rtab, **rtabp;
+
+ if (!tab || --tab->refcnt)
+ return;
+
+ for (rtabp = &qdisc_rtab_list; (rtab=*rtabp) != NULL; rtabp = &rtab->next) {
+ if (rtab == tab) {
+ *rtabp = rtab->next;
+ kfree(rtab);
+ return;
+ }
+ }
+}
+
+
+/* Allocate an unique handle from space managed by kernel */
+
+static u32 qdisc_alloc_handle(struct net_device *dev)
+{
+ int i = 0x10000;
+ static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
+
+ do {
+ autohandle += TC_H_MAKE(0x10000U, 0);
+ if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
+ autohandle = TC_H_MAKE(0x80000000U, 0);
+ } while (qdisc_lookup(dev, autohandle) && --i > 0);
+
+ return i>0 ? autohandle : 0;
+}
+
+/* Attach toplevel qdisc to device dev */
+
+static struct Qdisc *
+dev_graft_qdisc(struct net_device *dev, struct Qdisc *qdisc)
+{
+ struct Qdisc *oqdisc;
+
+ if (dev->flags & IFF_UP)
+ dev_deactivate(dev);
+
+ qdisc_lock_tree(dev);
+ if (qdisc && qdisc->flags&TCQ_F_INGRESS) {
+ oqdisc = dev->qdisc_ingress;
+ /* Prune old scheduler */
+ if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1) {
+ /* delete */
+ qdisc_reset(oqdisc);
+ dev->qdisc_ingress = NULL;
+ } else { /* new */
+ dev->qdisc_ingress = qdisc;
+ }
+
+ } else {
+
+ oqdisc = dev->qdisc_sleeping;
+
+ /* Prune old scheduler */
+ if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1)
+ qdisc_reset(oqdisc);
+
+ /* ... and graft new one */
+ if (qdisc == NULL)
+ qdisc = &noop_qdisc;
+ dev->qdisc_sleeping = qdisc;
+ dev->qdisc = &noop_qdisc;
+ }
+
+ qdisc_unlock_tree(dev);
+
+ if (dev->flags & IFF_UP)
+ dev_activate(dev);
+
+ return oqdisc;
+}
+
+
+/* Graft qdisc "new" to class "classid" of qdisc "parent" or
+ to device "dev".
+
+ Old qdisc is not destroyed but returned in *old.
+ */
+
+static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
+ u32 classid,
+ struct Qdisc *new, struct Qdisc **old)
+{
+ int err = 0;
+ struct Qdisc *q = *old;
+
+
+ if (parent == NULL) {
+ if (q && q->flags&TCQ_F_INGRESS) {
+ *old = dev_graft_qdisc(dev, q);
+ } else {
+ *old = dev_graft_qdisc(dev, new);
+ }
+ } else {
+ struct Qdisc_class_ops *cops = parent->ops->cl_ops;
+
+ err = -EINVAL;
+
+ if (cops) {
+ unsigned long cl = cops->get(parent, classid);
+ if (cl) {
+ err = cops->graft(parent, cl, new, old);
+ if (new)
+ new->parent = classid;
+ cops->put(parent, cl);
+ }
+ }
+ }
+ return err;
+}
+
+/*
+ Allocate and initialize new qdisc.
+
+ Parameters are passed via opt.
+ */
+
+static struct Qdisc *
+qdisc_create(struct net_device *dev, u32 handle, struct rtattr **tca, int *errp)
+{
+ int err;
+ struct rtattr *kind = tca[TCA_KIND-1];
+ void *p = NULL;
+ struct Qdisc *sch;
+ struct Qdisc_ops *ops;
+ int size;
+
+ ops = qdisc_lookup_ops(kind);
+#ifdef CONFIG_KMOD
+ if (ops == NULL && kind != NULL) {
+ char name[IFNAMSIZ];
+ if (rtattr_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
+ /* We dropped the RTNL semaphore in order to
+ * perform the module load. So, even if we
+ * succeeded in loading the module we have to
+ * tell the caller to replay the request. We
+ * indicate this using -EAGAIN.
+ * We replay the request because the device may
+ * go away in the mean time.
+ */
+ rtnl_unlock();
+ request_module("sch_%s", name);
+ rtnl_lock();
+ ops = qdisc_lookup_ops(kind);
+ if (ops != NULL) {
+ /* We will try again qdisc_lookup_ops,
+ * so don't keep a reference.
+ */
+ module_put(ops->owner);
+ err = -EAGAIN;
+ goto err_out;
+ }
+ }
+ }
+#endif
+
+ err = -EINVAL;
+ if (ops == NULL)
+ goto err_out;
+
+ /* ensure that the Qdisc and the private data are 32-byte aligned */
+ size = ((sizeof(*sch) + QDISC_ALIGN_CONST) & ~QDISC_ALIGN_CONST);
+ size += ops->priv_size + QDISC_ALIGN_CONST;
+
+ p = kmalloc(size, GFP_KERNEL);
+ err = -ENOBUFS;
+ if (!p)
+ goto err_out2;
+ memset(p, 0, size);
+ sch = (struct Qdisc *)(((unsigned long)p + QDISC_ALIGN_CONST)
+ & ~QDISC_ALIGN_CONST);
+ sch->padded = (char *)sch - (char *)p;
+
+ INIT_LIST_HEAD(&sch->list);
+ skb_queue_head_init(&sch->q);
+
+ if (handle == TC_H_INGRESS)
+ sch->flags |= TCQ_F_INGRESS;
+
+ sch->ops = ops;
+ sch->enqueue = ops->enqueue;
+ sch->dequeue = ops->dequeue;
+ sch->dev = dev;
+ dev_hold(dev);
+ atomic_set(&sch->refcnt, 1);
+ sch->stats_lock = &dev->queue_lock;
+ if (handle == 0) {
+ handle = qdisc_alloc_handle(dev);
+ err = -ENOMEM;
+ if (handle == 0)
+ goto err_out3;
+ }
+
+ if (handle == TC_H_INGRESS)
+ sch->handle =TC_H_MAKE(TC_H_INGRESS, 0);
+ else
+ sch->handle = handle;
+
+ if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS-1])) == 0) {
+ qdisc_lock_tree(dev);
+ list_add_tail(&sch->list, &dev->qdisc_list);
+ qdisc_unlock_tree(dev);
+
+#ifdef CONFIG_NET_ESTIMATOR
+ if (tca[TCA_RATE-1])
+ gen_new_estimator(&sch->bstats, &sch->rate_est,
+ sch->stats_lock, tca[TCA_RATE-1]);
+#endif
+ return sch;
+ }
+err_out3:
+ dev_put(dev);
+err_out2:
+ module_put(ops->owner);
+err_out:
+ *errp = err;
+ if (p)
+ kfree(p);
+ return NULL;
+}
+
+static int qdisc_change(struct Qdisc *sch, struct rtattr **tca)
+{
+ if (tca[TCA_OPTIONS-1]) {
+ int err;
+
+ if (sch->ops->change == NULL)
+ return -EINVAL;
+ err = sch->ops->change(sch, tca[TCA_OPTIONS-1]);
+ if (err)
+ return err;
+ }
+#ifdef CONFIG_NET_ESTIMATOR
+ if (tca[TCA_RATE-1])
+ gen_replace_estimator(&sch->bstats, &sch->rate_est,
+ sch->stats_lock, tca[TCA_RATE-1]);
+#endif
+ return 0;
+}
+
+struct check_loop_arg
+{
+ struct qdisc_walker w;
+ struct Qdisc *p;
+ int depth;
+};
+
+static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w);
+
+static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
+{
+ struct check_loop_arg arg;
+
+ if (q->ops->cl_ops == NULL)
+ return 0;
+
+ arg.w.stop = arg.w.skip = arg.w.count = 0;
+ arg.w.fn = check_loop_fn;
+ arg.depth = depth;
+ arg.p = p;
+ q->ops->cl_ops->walk(q, &arg.w);
+ return arg.w.stop ? -ELOOP : 0;
+}
+
+static int
+check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
+{
+ struct Qdisc *leaf;
+ struct Qdisc_class_ops *cops = q->ops->cl_ops;
+ struct check_loop_arg *arg = (struct check_loop_arg *)w;
+
+ leaf = cops->leaf(q, cl);
+ if (leaf) {
+ if (leaf == arg->p || arg->depth > 7)
+ return -ELOOP;
+ return check_loop(leaf, arg->p, arg->depth + 1);
+ }
+ return 0;
+}
+
+/*
+ * Delete/get qdisc.
+ */
+
+static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+{
+ struct tcmsg *tcm = NLMSG_DATA(n);
+ struct rtattr **tca = arg;
+ struct net_device *dev;
+ u32 clid = tcm->tcm_parent;
+ struct Qdisc *q = NULL;
+ struct Qdisc *p = NULL;
+ int err;
+
+ if ((dev = __dev_get_by_index(tcm->tcm_ifindex)) == NULL)
+ return -ENODEV;
+
+ if (clid) {
+ if (clid != TC_H_ROOT) {
+ if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
+ if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL)
+ return -ENOENT;
+ q = qdisc_leaf(p, clid);
+ } else { /* ingress */
+ q = dev->qdisc_ingress;
+ }
+ } else {
+ q = dev->qdisc_sleeping;
+ }
+ if (!q)
+ return -ENOENT;
+
+ if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
+ return -EINVAL;
+ } else {
+ if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL)
+ return -ENOENT;
+ }
+
+ if (tca[TCA_KIND-1] && rtattr_strcmp(tca[TCA_KIND-1], q->ops->id))
+ return -EINVAL;
+
+ if (n->nlmsg_type == RTM_DELQDISC) {
+ if (!clid)
+ return -EINVAL;
+ if (q->handle == 0)
+ return -ENOENT;
+ if ((err = qdisc_graft(dev, p, clid, NULL, &q)) != 0)
+ return err;
+ if (q) {
+ qdisc_notify(skb, n, clid, q, NULL);
+ spin_lock_bh(&dev->queue_lock);
+ qdisc_destroy(q);
+ spin_unlock_bh(&dev->queue_lock);
+ }
+ } else {
+ qdisc_notify(skb, n, clid, NULL, q);
+ }
+ return 0;
+}
+
+/*
+ Create/change qdisc.
+ */
+
+static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+{
+ struct tcmsg *tcm;
+ struct rtattr **tca;
+ struct net_device *dev;
+ u32 clid;
+ struct Qdisc *q, *p;
+ int err;
+
+replay:
+ /* Reinit, just in case something touches this. */
+ tcm = NLMSG_DATA(n);
+ tca = arg;
+ clid = tcm->tcm_parent;
+ q = p = NULL;
+
+ if ((dev = __dev_get_by_index(tcm->tcm_ifindex)) == NULL)
+ return -ENODEV;
+
+ if (clid) {
+ if (clid != TC_H_ROOT) {
+ if (clid != TC_H_INGRESS) {
+ if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL)
+ return -ENOENT;
+ q = qdisc_leaf(p, clid);
+ } else { /*ingress */
+ q = dev->qdisc_ingress;
+ }
+ } else {
+ q = dev->qdisc_sleeping;
+ }
+
+ /* It may be default qdisc, ignore it */
+ if (q && q->handle == 0)
+ q = NULL;
+
+ if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
+ if (tcm->tcm_handle) {
+ if (q && !(n->nlmsg_flags&NLM_F_REPLACE))
+ return -EEXIST;
+ if (TC_H_MIN(tcm->tcm_handle))
+ return -EINVAL;
+ if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL)
+ goto create_n_graft;
+ if (n->nlmsg_flags&NLM_F_EXCL)
+ return -EEXIST;
+ if (tca[TCA_KIND-1] && rtattr_strcmp(tca[TCA_KIND-1], q->ops->id))
+ return -EINVAL;
+ if (q == p ||
+ (p && check_loop(q, p, 0)))
+ return -ELOOP;
+ atomic_inc(&q->refcnt);
+ goto graft;
+ } else {
+ if (q == NULL)
+ goto create_n_graft;
+
+ /* This magic test requires explanation.
+ *
+ * We know, that some child q is already
+ * attached to this parent and have choice:
+ * either to change it or to create/graft new one.
+ *
+ * 1. We are allowed to create/graft only
+ * if CREATE and REPLACE flags are set.
+ *
+ * 2. If EXCL is set, requestor wanted to say,
+ * that qdisc tcm_handle is not expected
+ * to exist, so that we choose create/graft too.
+ *
+ * 3. The last case is when no flags are set.
+ * Alas, it is sort of hole in API, we
+ * cannot decide what to do unambiguously.
+ * For now we select create/graft, if
+ * user gave KIND, which does not match existing.
+ */
+ if ((n->nlmsg_flags&NLM_F_CREATE) &&
+ (n->nlmsg_flags&NLM_F_REPLACE) &&
+ ((n->nlmsg_flags&NLM_F_EXCL) ||
+ (tca[TCA_KIND-1] &&
+ rtattr_strcmp(tca[TCA_KIND-1], q->ops->id))))
+ goto create_n_graft;
+ }
+ }
+ } else {
+ if (!tcm->tcm_handle)
+ return -EINVAL;
+ q = qdisc_lookup(dev, tcm->tcm_handle);
+ }
+
+ /* Change qdisc parameters */
+ if (q == NULL)
+ return -ENOENT;
+ if (n->nlmsg_flags&NLM_F_EXCL)
+ return -EEXIST;
+ if (tca[TCA_KIND-1] && rtattr_strcmp(tca[TCA_KIND-1], q->ops->id))
+ return -EINVAL;
+ err = qdisc_change(q, tca);
+ if (err == 0)
+ qdisc_notify(skb, n, clid, NULL, q);
+ return err;
+
+create_n_graft:
+ if (!(n->nlmsg_flags&NLM_F_CREATE))
+ return -ENOENT;
+ if (clid == TC_H_INGRESS)
+ q = qdisc_create(dev, tcm->tcm_parent, tca, &err);
+ else
+ q = qdisc_create(dev, tcm->tcm_handle, tca, &err);
+ if (q == NULL) {
+ if (err == -EAGAIN)
+ goto replay;
+ return err;
+ }
+
+graft:
+ if (1) {
+ struct Qdisc *old_q = NULL;
+ err = qdisc_graft(dev, p, clid, q, &old_q);
+ if (err) {
+ if (q) {
+ spin_lock_bh(&dev->queue_lock);
+ qdisc_destroy(q);
+ spin_unlock_bh(&dev->queue_lock);
+ }
+ return err;
+ }
+ qdisc_notify(skb, n, clid, old_q, q);
+ if (old_q) {
+ spin_lock_bh(&dev->queue_lock);
+ qdisc_destroy(old_q);
+ spin_unlock_bh(&dev->queue_lock);
+ }
+ }
+ return 0;
+}
+
+static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
+ u32 pid, u32 seq, unsigned flags, int event)
+{
+ struct tcmsg *tcm;
+ struct nlmsghdr *nlh;
+ unsigned char *b = skb->tail;
+ struct gnet_dump d;
+
+ nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*tcm));
+ nlh->nlmsg_flags = flags;
+ tcm = NLMSG_DATA(nlh);
+ tcm->tcm_family = AF_UNSPEC;
+ tcm->tcm_ifindex = q->dev->ifindex;
+ tcm->tcm_parent = clid;
+ tcm->tcm_handle = q->handle;
+ tcm->tcm_info = atomic_read(&q->refcnt);
+ RTA_PUT(skb, TCA_KIND, IFNAMSIZ, q->ops->id);
+ if (q->ops->dump && q->ops->dump(q, skb) < 0)
+ goto rtattr_failure;
+ q->qstats.qlen = q->q.qlen;
+
+ if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS,
+ TCA_XSTATS, q->stats_lock, &d) < 0)
+ goto rtattr_failure;
+
+ if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
+ goto rtattr_failure;
+
+ if (gnet_stats_copy_basic(&d, &q->bstats) < 0 ||
+#ifdef CONFIG_NET_ESTIMATOR
+ gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
+#endif
+ gnet_stats_copy_queue(&d, &q->qstats) < 0)
+ goto rtattr_failure;
+
+ if (gnet_stats_finish_copy(&d) < 0)
+ goto rtattr_failure;
+
+ nlh->nlmsg_len = skb->tail - b;
+ return skb->len;
+
+nlmsg_failure:
+rtattr_failure:
+ skb_trim(skb, b - skb->data);
+ return -1;
+}
+
+static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n,
+ u32 clid, struct Qdisc *old, struct Qdisc *new)
+{
+ struct sk_buff *skb;
+ u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
+
+ skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+ if (!skb)
+ return -ENOBUFS;
+
+ if (old && old->handle) {
+ if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq, 0, RTM_DELQDISC) < 0)
+ goto err_out;
+ }
+ if (new) {
+ if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq, old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
+ goto err_out;
+ }
+
+ if (skb->len)
+ return rtnetlink_send(skb, pid, RTMGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
+
+err_out:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ int idx, q_idx;
+ int s_idx, s_q_idx;
+ struct net_device *dev;
+ struct Qdisc *q;
+
+ s_idx = cb->args[0];
+ s_q_idx = q_idx = cb->args[1];
+ read_lock(&dev_base_lock);
+ for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
+ if (idx < s_idx)
+ continue;
+ if (idx > s_idx)
+ s_q_idx = 0;
+ read_lock_bh(&qdisc_tree_lock);
+ q_idx = 0;
+ list_for_each_entry(q, &dev->qdisc_list, list) {
+ if (q_idx < s_q_idx) {
+ q_idx++;
+ continue;
+ }
+ if (tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid,
+ cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) {
+ read_unlock_bh(&qdisc_tree_lock);
+ goto done;
+ }
+ q_idx++;
+ }
+ read_unlock_bh(&qdisc_tree_lock);
+ }
+
+done:
+ read_unlock(&dev_base_lock);
+
+ cb->args[0] = idx;
+ cb->args[1] = q_idx;
+
+ return skb->len;
+}
+
+
+
+/************************************************
+ * Traffic classes manipulation. *
+ ************************************************/
+
+
+
+static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+{
+ struct tcmsg *tcm = NLMSG_DATA(n);
+ struct rtattr **tca = arg;
+ struct net_device *dev;
+ struct Qdisc *q = NULL;
+ struct Qdisc_class_ops *cops;
+ unsigned long cl = 0;
+ unsigned long new_cl;
+ u32 pid = tcm->tcm_parent;
+ u32 clid = tcm->tcm_handle;
+ u32 qid = TC_H_MAJ(clid);
+ int err;
+
+ if ((dev = __dev_get_by_index(tcm->tcm_ifindex)) == NULL)
+ return -ENODEV;
+
+ /*
+ parent == TC_H_UNSPEC - unspecified parent.
+ parent == TC_H_ROOT - class is root, which has no parent.
+ parent == X:0 - parent is root class.
+ parent == X:Y - parent is a node in hierarchy.
+ parent == 0:Y - parent is X:Y, where X:0 is qdisc.
+
+ handle == 0:0 - generate handle from kernel pool.
+ handle == 0:Y - class is X:Y, where X:0 is qdisc.
+ handle == X:Y - clear.
+ handle == X:0 - root class.
+ */
+
+ /* Step 1. Determine qdisc handle X:0 */
+
+ if (pid != TC_H_ROOT) {
+ u32 qid1 = TC_H_MAJ(pid);
+
+ if (qid && qid1) {
+ /* If both majors are known, they must be identical. */
+ if (qid != qid1)
+ return -EINVAL;
+ } else if (qid1) {
+ qid = qid1;
+ } else if (qid == 0)
+ qid = dev->qdisc_sleeping->handle;
+
+ /* Now qid is genuine qdisc handle consistent
+ both with parent and child.
+
+ TC_H_MAJ(pid) still may be unspecified, complete it now.
+ */
+ if (pid)
+ pid = TC_H_MAKE(qid, pid);
+ } else {
+ if (qid == 0)
+ qid = dev->qdisc_sleeping->handle;
+ }
+
+ /* OK. Locate qdisc */
+ if ((q = qdisc_lookup(dev, qid)) == NULL)
+ return -ENOENT;
+
+ /* An check that it supports classes */
+ cops = q->ops->cl_ops;
+ if (cops == NULL)
+ return -EINVAL;
+
+ /* Now try to get class */
+ if (clid == 0) {
+ if (pid == TC_H_ROOT)
+ clid = qid;
+ } else
+ clid = TC_H_MAKE(qid, clid);
+
+ if (clid)
+ cl = cops->get(q, clid);
+
+ if (cl == 0) {
+ err = -ENOENT;
+ if (n->nlmsg_type != RTM_NEWTCLASS || !(n->nlmsg_flags&NLM_F_CREATE))
+ goto out;
+ } else {
+ switch (n->nlmsg_type) {
+ case RTM_NEWTCLASS:
+ err = -EEXIST;
+ if (n->nlmsg_flags&NLM_F_EXCL)
+ goto out;
+ break;
+ case RTM_DELTCLASS:
+ err = cops->delete(q, cl);
+ if (err == 0)
+ tclass_notify(skb, n, q, cl, RTM_DELTCLASS);
+ goto out;
+ case RTM_GETTCLASS:
+ err = tclass_notify(skb, n, q, cl, RTM_NEWTCLASS);
+ goto out;
+ default:
+ err = -EINVAL;
+ goto out;
+ }
+ }
+
+ new_cl = cl;
+ err = cops->change(q, clid, pid, tca, &new_cl);
+ if (err == 0)
+ tclass_notify(skb, n, q, new_cl, RTM_NEWTCLASS);
+
+out:
+ if (cl)
+ cops->put(q, cl);
+
+ return err;
+}
+
+
+static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
+ unsigned long cl,
+ u32 pid, u32 seq, unsigned flags, int event)
+{
+ struct tcmsg *tcm;
+ struct nlmsghdr *nlh;
+ unsigned char *b = skb->tail;
+ struct gnet_dump d;
+ struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
+
+ nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*tcm));
+ nlh->nlmsg_flags = flags;
+ tcm = NLMSG_DATA(nlh);
+ tcm->tcm_family = AF_UNSPEC;
+ tcm->tcm_ifindex = q->dev->ifindex;
+ tcm->tcm_parent = q->handle;
+ tcm->tcm_handle = q->handle;
+ tcm->tcm_info = 0;
+ RTA_PUT(skb, TCA_KIND, IFNAMSIZ, q->ops->id);
+ if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
+ goto rtattr_failure;
+
+ if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS,
+ TCA_XSTATS, q->stats_lock, &d) < 0)
+ goto rtattr_failure;
+
+ if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
+ goto rtattr_failure;
+
+ if (gnet_stats_finish_copy(&d) < 0)
+ goto rtattr_failure;
+
+ nlh->nlmsg_len = skb->tail - b;
+ return skb->len;
+
+nlmsg_failure:
+rtattr_failure:
+ skb_trim(skb, b - skb->data);
+ return -1;
+}
+
+static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n,
+ struct Qdisc *q, unsigned long cl, int event)
+{
+ struct sk_buff *skb;
+ u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
+
+ skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+ if (!skb)
+ return -ENOBUFS;
+
+ if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+
+ return rtnetlink_send(skb, pid, RTMGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
+}
+
+struct qdisc_dump_args
+{
+ struct qdisc_walker w;
+ struct sk_buff *skb;
+ struct netlink_callback *cb;
+};
+
+static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg)
+{
+ struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
+
+ return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid,
+ a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
+}
+
+static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ int t;
+ int s_t;
+ struct net_device *dev;
+ struct Qdisc *q;
+ struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh);
+ struct qdisc_dump_args arg;
+
+ if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
+ return 0;
+ if ((dev = dev_get_by_index(tcm->tcm_ifindex)) == NULL)
+ return 0;
+
+ s_t = cb->args[0];
+ t = 0;
+
+ read_lock_bh(&qdisc_tree_lock);
+ list_for_each_entry(q, &dev->qdisc_list, list) {
+ if (t < s_t || !q->ops->cl_ops ||
+ (tcm->tcm_parent &&
+ TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
+ t++;
+ continue;
+ }
+ if (t > s_t)
+ memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
+ arg.w.fn = qdisc_class_dump;
+ arg.skb = skb;
+ arg.cb = cb;
+ arg.w.stop = 0;
+ arg.w.skip = cb->args[1];
+ arg.w.count = 0;
+ q->ops->cl_ops->walk(q, &arg.w);
+ cb->args[1] = arg.w.count;
+ if (arg.w.stop)
+ break;
+ t++;
+ }
+ read_unlock_bh(&qdisc_tree_lock);
+
+ cb->args[0] = t;
+
+ dev_put(dev);
+ return skb->len;
+}
+
+/* Main classifier routine: scans classifier chain attached
+ to this qdisc, (optionally) tests for protocol and asks
+ specific classifiers.
+ */
+int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
+ struct tcf_result *res)
+{
+ int err = 0;
+ u32 protocol = skb->protocol;
+#ifdef CONFIG_NET_CLS_ACT
+ struct tcf_proto *otp = tp;
+reclassify:
+#endif
+ protocol = skb->protocol;
+
+ for ( ; tp; tp = tp->next) {
+ if ((tp->protocol == protocol ||
+ tp->protocol == __constant_htons(ETH_P_ALL)) &&
+ (err = tp->classify(skb, tp, res)) >= 0) {
+#ifdef CONFIG_NET_CLS_ACT
+ if ( TC_ACT_RECLASSIFY == err) {
+ __u32 verd = (__u32) G_TC_VERD(skb->tc_verd);
+ tp = otp;
+
+ if (MAX_REC_LOOP < verd++) {
+ printk("rule prio %d protocol %02x reclassify is buggy packet dropped\n",
+ tp->prio&0xffff, ntohs(tp->protocol));
+ return TC_ACT_SHOT;
+ }
+ skb->tc_verd = SET_TC_VERD(skb->tc_verd,verd);
+ goto reclassify;
+ } else {
+ if (skb->tc_verd)
+ skb->tc_verd = SET_TC_VERD(skb->tc_verd,0);
+ return err;
+ }
+#else
+
+ return err;
+#endif
+ }
+
+ }
+ return -1;
+}
+
+static int psched_us_per_tick = 1;
+static int psched_tick_per_us = 1;
+
+#ifdef CONFIG_PROC_FS
+static int psched_show(struct seq_file *seq, void *v)
+{
+ seq_printf(seq, "%08x %08x %08x %08x\n",
+ psched_tick_per_us, psched_us_per_tick,
+ 1000000, HZ);
+
+ return 0;
+}
+
+static int psched_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, psched_show, PDE(inode)->data);
+}
+
+static struct file_operations psched_fops = {
+ .owner = THIS_MODULE,
+ .open = psched_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+#endif
+
+#ifdef CONFIG_NET_SCH_CLK_CPU
+psched_tdiff_t psched_clock_per_hz;
+int psched_clock_scale;
+EXPORT_SYMBOL(psched_clock_per_hz);
+EXPORT_SYMBOL(psched_clock_scale);
+
+psched_time_t psched_time_base;
+cycles_t psched_time_mark;
+EXPORT_SYMBOL(psched_time_mark);
+EXPORT_SYMBOL(psched_time_base);
+
+/*
+ * Periodically adjust psched_time_base to avoid overflow
+ * with 32-bit get_cycles(). Safe up to 4GHz CPU.
+ */
+static void psched_tick(unsigned long);
+static struct timer_list psched_timer = TIMER_INITIALIZER(psched_tick, 0, 0);
+
+static void psched_tick(unsigned long dummy)
+{
+ if (sizeof(cycles_t) == sizeof(u32)) {
+ psched_time_t dummy_stamp;
+ PSCHED_GET_TIME(dummy_stamp);
+ psched_timer.expires = jiffies + 1*HZ;
+ add_timer(&psched_timer);
+ }
+}
+
+int __init psched_calibrate_clock(void)
+{
+ psched_time_t stamp, stamp1;
+ struct timeval tv, tv1;
+ psched_tdiff_t delay;
+ long rdelay;
+ unsigned long stop;
+
+ psched_tick(0);
+ stop = jiffies + HZ/10;
+ PSCHED_GET_TIME(stamp);
+ do_gettimeofday(&tv);
+ while (time_before(jiffies, stop)) {
+ barrier();
+ cpu_relax();
+ }
+ PSCHED_GET_TIME(stamp1);
+ do_gettimeofday(&tv1);
+
+ delay = PSCHED_TDIFF(stamp1, stamp);
+ rdelay = tv1.tv_usec - tv.tv_usec;
+ rdelay += (tv1.tv_sec - tv.tv_sec)*1000000;
+ if (rdelay > delay)
+ return -1;
+ delay /= rdelay;
+ psched_tick_per_us = delay;
+ while ((delay>>=1) != 0)
+ psched_clock_scale++;
+ psched_us_per_tick = 1<<psched_clock_scale;
+ psched_clock_per_hz = (psched_tick_per_us*(1000000/HZ))>>psched_clock_scale;
+ return 0;
+}
+#endif
+
+static int __init pktsched_init(void)
+{
+ struct rtnetlink_link *link_p;
+
+#ifdef CONFIG_NET_SCH_CLK_CPU
+ if (psched_calibrate_clock() < 0)
+ return -1;
+#elif defined(CONFIG_NET_SCH_CLK_JIFFIES)
+ psched_tick_per_us = HZ<<PSCHED_JSCALE;
+ psched_us_per_tick = 1000000;
+#endif
+
+ link_p = rtnetlink_links[PF_UNSPEC];
+
+ /* Setup rtnetlink links. It is made here to avoid
+ exporting large number of public symbols.
+ */
+
+ if (link_p) {
+ link_p[RTM_NEWQDISC-RTM_BASE].doit = tc_modify_qdisc;
+ link_p[RTM_DELQDISC-RTM_BASE].doit = tc_get_qdisc;
+ link_p[RTM_GETQDISC-RTM_BASE].doit = tc_get_qdisc;
+ link_p[RTM_GETQDISC-RTM_BASE].dumpit = tc_dump_qdisc;
+ link_p[RTM_NEWTCLASS-RTM_BASE].doit = tc_ctl_tclass;
+ link_p[RTM_DELTCLASS-RTM_BASE].doit = tc_ctl_tclass;
+ link_p[RTM_GETTCLASS-RTM_BASE].doit = tc_ctl_tclass;
+ link_p[RTM_GETTCLASS-RTM_BASE].dumpit = tc_dump_tclass;
+ }
+
+ register_qdisc(&pfifo_qdisc_ops);
+ register_qdisc(&bfifo_qdisc_ops);
+ proc_net_fops_create("psched", 0, &psched_fops);
+
+ return 0;
+}
+
+subsys_initcall(pktsched_init);
+
+EXPORT_SYMBOL(qdisc_get_rtab);
+EXPORT_SYMBOL(qdisc_put_rtab);
+EXPORT_SYMBOL(register_qdisc);
+EXPORT_SYMBOL(unregister_qdisc);
+EXPORT_SYMBOL(tc_classify);
