1 files changed, 522 insertions, 0 deletions

diff --git a/net/sched/sch_dsmark.c b/net/sched/sch_dsmark.c
new file mode 100644
index 0000000..ba43aab
--- /dev/null
+++ b/net/sched/sch_dsmark.c
@@ -0,0 +1,522 @@
+/* net/sched/sch_dsmark.c - Differentiated Services field marker */
+
+/* Written 1998-2000 by Werner Almesberger, EPFL ICA */
+
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/bitops.h>
+#include <net/pkt_sched.h>
+#include <net/dsfield.h>
+#include <net/inet_ecn.h>
+#include <asm/byteorder.h>
+
+/*
+ * classid	class		marking
+ * -------	-----		-------
+ *   n/a	  0		n/a
+ *   x:0	  1		use entry [0]
+ *   ...	 ...		...
+ *   x:y y>0	 y+1		use entry [y]
+ *   ...	 ...		...
+ * x:indices-1	indices		use entry [indices-1]
+ *   ...	 ...		...
+ *   x:y	 y+1		use entry [y & (indices-1)]
+ *   ...	 ...		...
+ * 0xffff	0x10000		use entry [indices-1]
+ */
+
+
+#define NO_DEFAULT_INDEX	(1 << 16)
+
+struct dsmark_qdisc_data {
+	struct Qdisc		*q;
+	struct tcf_proto	*filter_list;
+	u8			*mask;	/* "owns" the array */
+	u8			*value;
+	u16			indices;
+	u32			default_index;	/* index range is 0...0xffff */
+	int			set_tc_index;
+};
+
+static inline int dsmark_valid_index(struct dsmark_qdisc_data *p, u16 index)
+{
+	return (index <= p->indices && index > 0);
+}
+
+/* ------------------------- Class/flow operations ------------------------- */
+
+static int dsmark_graft(struct Qdisc *sch, unsigned long arg,
+			struct Qdisc *new, struct Qdisc **old)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+
+	pr_debug("dsmark_graft(sch %p,[qdisc %p],new %p,old %p)\n",
+		sch, p, new, old);
+
+	if (new == NULL) {
+		new = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
+					&pfifo_qdisc_ops,
+					sch->handle);
+		if (new == NULL)
+			new = &noop_qdisc;
+	}
+
+	sch_tree_lock(sch);
+	*old = xchg(&p->q, new);
+	qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
+	qdisc_reset(*old);
+	sch_tree_unlock(sch);
+
+	return 0;
+}
+
+static struct Qdisc *dsmark_leaf(struct Qdisc *sch, unsigned long arg)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	return p->q;
+}
+
+static unsigned long dsmark_get(struct Qdisc *sch, u32 classid)
+{
+	pr_debug("dsmark_get(sch %p,[qdisc %p],classid %x)\n",
+		sch, qdisc_priv(sch), classid);
+
+	return TC_H_MIN(classid) + 1;
+}
+
+static unsigned long dsmark_bind_filter(struct Qdisc *sch,
+					unsigned long parent, u32 classid)
+{
+	return dsmark_get(sch, classid);
+}
+
+static void dsmark_put(struct Qdisc *sch, unsigned long cl)
+{
+}
+
+static const struct nla_policy dsmark_policy[TCA_DSMARK_MAX + 1] = {
+	[TCA_DSMARK_INDICES]		= { .type = NLA_U16 },
+	[TCA_DSMARK_DEFAULT_INDEX]	= { .type = NLA_U16 },
+	[TCA_DSMARK_SET_TC_INDEX]	= { .type = NLA_FLAG },
+	[TCA_DSMARK_MASK]		= { .type = NLA_U8 },
+	[TCA_DSMARK_VALUE]		= { .type = NLA_U8 },
+};
+
+static int dsmark_change(struct Qdisc *sch, u32 classid, u32 parent,
+			 struct nlattr **tca, unsigned long *arg)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	struct nlattr *opt = tca[TCA_OPTIONS];
+	struct nlattr *tb[TCA_DSMARK_MAX + 1];
+	int err = -EINVAL;
+	u8 mask = 0;
+
+	pr_debug("dsmark_change(sch %p,[qdisc %p],classid %x,parent %x),"
+		"arg 0x%lx\n", sch, p, classid, parent, *arg);
+
+	if (!dsmark_valid_index(p, *arg)) {
+		err = -ENOENT;
+		goto errout;
+	}
+
+	if (!opt)
+		goto errout;
+
+	err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
+	if (err < 0)
+		goto errout;
+
+	if (tb[TCA_DSMARK_MASK])
+		mask = nla_get_u8(tb[TCA_DSMARK_MASK]);
+
+	if (tb[TCA_DSMARK_VALUE])
+		p->value[*arg-1] = nla_get_u8(tb[TCA_DSMARK_VALUE]);
+
+	if (tb[TCA_DSMARK_MASK])
+		p->mask[*arg-1] = mask;
+
+	err = 0;
+
+errout:
+	return err;
+}
+
+static int dsmark_delete(struct Qdisc *sch, unsigned long arg)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+
+	if (!dsmark_valid_index(p, arg))
+		return -EINVAL;
+
+	p->mask[arg-1] = 0xff;
+	p->value[arg-1] = 0;
+
+	return 0;
+}
+
+static void dsmark_walk(struct Qdisc *sch, struct qdisc_walker *walker)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	int i;
+
+	pr_debug("dsmark_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
+
+	if (walker->stop)
+		return;
+
+	for (i = 0; i < p->indices; i++) {
+		if (p->mask[i] == 0xff && !p->value[i])
+			goto ignore;
+		if (walker->count >= walker->skip) {
+			if (walker->fn(sch, i+1, walker) < 0) {
+				walker->stop = 1;
+				break;
+			}
+		}
+ignore:
+		walker->count++;
+	}
+}
+
+static inline struct tcf_proto **dsmark_find_tcf(struct Qdisc *sch,
+						 unsigned long cl)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	return &p->filter_list;
+}
+
+/* --------------------------- Qdisc operations ---------------------------- */
+
+static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	int err;
+
+	pr_debug("dsmark_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
+
+	if (p->set_tc_index) {
+		switch (skb->protocol) {
+		case htons(ETH_P_IP):
+			if (skb_cow_head(skb, sizeof(struct iphdr)))
+				goto drop;
+
+			skb->tc_index = ipv4_get_dsfield(ip_hdr(skb))
+				& ~INET_ECN_MASK;
+			break;
+
+		case htons(ETH_P_IPV6):
+			if (skb_cow_head(skb, sizeof(struct ipv6hdr)))
+				goto drop;
+
+			skb->tc_index = ipv6_get_dsfield(ipv6_hdr(skb))
+				& ~INET_ECN_MASK;
+			break;
+		default:
+			skb->tc_index = 0;
+			break;
+		}
+	}
+
+	if (TC_H_MAJ(skb->priority) == sch->handle)
+		skb->tc_index = TC_H_MIN(skb->priority);
+	else {
+		struct tcf_result res;
+		int result = tc_classify(skb, p->filter_list, &res);
+
+		pr_debug("result %d class 0x%04x\n", result, res.classid);
+
+		switch (result) {
+#ifdef CONFIG_NET_CLS_ACT
+		case TC_ACT_QUEUED:
+		case TC_ACT_STOLEN:
+			kfree_skb(skb);
+			return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
+
+		case TC_ACT_SHOT:
+			goto drop;
+#endif
+		case TC_ACT_OK:
+			skb->tc_index = TC_H_MIN(res.classid);
+			break;
+
+		default:
+			if (p->default_index != NO_DEFAULT_INDEX)
+				skb->tc_index = p->default_index;
+			break;
+		}
+	}
+
+	err = qdisc_enqueue(skb, p->q);
+	if (err != NET_XMIT_SUCCESS) {
+		if (net_xmit_drop_count(err))
+			sch->qstats.drops++;
+		return err;
+	}
+
+	sch->bstats.bytes += qdisc_pkt_len(skb);
+	sch->bstats.packets++;
+	sch->q.qlen++;
+
+	return NET_XMIT_SUCCESS;
+
+drop:
+	kfree_skb(skb);
+	sch->qstats.drops++;
+	return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
+}
+
+static struct sk_buff *dsmark_dequeue(struct Qdisc *sch)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	struct sk_buff *skb;
+	u32 index;
+
+	pr_debug("dsmark_dequeue(sch %p,[qdisc %p])\n", sch, p);
+
+	skb = p->q->ops->dequeue(p->q);
+	if (skb == NULL)
+		return NULL;
+
+	sch->q.qlen--;
+
+	index = skb->tc_index & (p->indices - 1);
+	pr_debug("index %d->%d\n", skb->tc_index, index);
+
+	switch (skb->protocol) {
+	case htons(ETH_P_IP):
+		ipv4_change_dsfield(ip_hdr(skb), p->mask[index],
+				    p->value[index]);
+			break;
+	case htons(ETH_P_IPV6):
+		ipv6_change_dsfield(ipv6_hdr(skb), p->mask[index],
+				    p->value[index]);
+			break;
+	default:
+		/*
+		 * Only complain if a change was actually attempted.
+		 * This way, we can send non-IP traffic through dsmark
+		 * and don't need yet another qdisc as a bypass.
+		 */
+		if (p->mask[index] != 0xff || p->value[index])
+			printk(KERN_WARNING
+			       "dsmark_dequeue: unsupported protocol %d\n",
+			       ntohs(skb->protocol));
+		break;
+	}
+
+	return skb;
+}
+
+static int dsmark_requeue(struct sk_buff *skb, struct Qdisc *sch)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	int err;
+
+	pr_debug("dsmark_requeue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
+
+	err = p->q->ops->requeue(skb, p->q);
+	if (err != NET_XMIT_SUCCESS) {
+		if (net_xmit_drop_count(err))
+			sch->qstats.drops++;
+		return err;
+	}
+
+	sch->q.qlen++;
+	sch->qstats.requeues++;
+
+	return NET_XMIT_SUCCESS;
+}
+
+static unsigned int dsmark_drop(struct Qdisc *sch)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	unsigned int len;
+
+	pr_debug("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
+
+	if (p->q->ops->drop == NULL)
+		return 0;
+
+	len = p->q->ops->drop(p->q);
+	if (len)
+		sch->q.qlen--;
+
+	return len;
+}
+
+static int dsmark_init(struct Qdisc *sch, struct nlattr *opt)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	struct nlattr *tb[TCA_DSMARK_MAX + 1];
+	int err = -EINVAL;
+	u32 default_index = NO_DEFAULT_INDEX;
+	u16 indices;
+	u8 *mask;
+
+	pr_debug("dsmark_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
+
+	if (!opt)
+		goto errout;
+
+	err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
+	if (err < 0)
+		goto errout;
+
+	err = -EINVAL;
+	indices = nla_get_u16(tb[TCA_DSMARK_INDICES]);
+
+	if (hweight32(indices) != 1)
+		goto errout;
+
+	if (tb[TCA_DSMARK_DEFAULT_INDEX])
+		default_index = nla_get_u16(tb[TCA_DSMARK_DEFAULT_INDEX]);
+
+	mask = kmalloc(indices * 2, GFP_KERNEL);
+	if (mask == NULL) {
+		err = -ENOMEM;
+		goto errout;
+	}
+
+	p->mask = mask;
+	memset(p->mask, 0xff, indices);
+
+	p->value = p->mask + indices;
+	memset(p->value, 0, indices);
+
+	p->indices = indices;
+	p->default_index = default_index;
+	p->set_tc_index = nla_get_flag(tb[TCA_DSMARK_SET_TC_INDEX]);
+
+	p->q = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
+				 &pfifo_qdisc_ops, sch->handle);
+	if (p->q == NULL)
+		p->q = &noop_qdisc;
+
+	pr_debug("dsmark_init: qdisc %p\n", p->q);
+
+	err = 0;
+errout:
+	return err;
+}
+
+static void dsmark_reset(struct Qdisc *sch)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+
+	pr_debug("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
+	qdisc_reset(p->q);
+	sch->q.qlen = 0;
+}
+
+static void dsmark_destroy(struct Qdisc *sch)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+
+	pr_debug("dsmark_destroy(sch %p,[qdisc %p])\n", sch, p);
+
+	tcf_destroy_chain(&p->filter_list);
+	qdisc_destroy(p->q);
+	kfree(p->mask);
+}
+
+static int dsmark_dump_class(struct Qdisc *sch, unsigned long cl,
+			     struct sk_buff *skb, struct tcmsg *tcm)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	struct nlattr *opts = NULL;
+
+	pr_debug("dsmark_dump_class(sch %p,[qdisc %p],class %ld\n", sch, p, cl);
+
+	if (!dsmark_valid_index(p, cl))
+		return -EINVAL;
+
+	tcm->tcm_handle = TC_H_MAKE(TC_H_MAJ(sch->handle), cl-1);
+	tcm->tcm_info = p->q->handle;
+
+	opts = nla_nest_start(skb, TCA_OPTIONS);
+	if (opts == NULL)
+		goto nla_put_failure;
+	NLA_PUT_U8(skb, TCA_DSMARK_MASK, p->mask[cl-1]);
+	NLA_PUT_U8(skb, TCA_DSMARK_VALUE, p->value[cl-1]);
+
+	return nla_nest_end(skb, opts);
+
+nla_put_failure:
+	nla_nest_cancel(skb, opts);
+	return -EMSGSIZE;
+}
+
+static int dsmark_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+	struct dsmark_qdisc_data *p = qdisc_priv(sch);
+	struct nlattr *opts = NULL;
+
+	opts = nla_nest_start(skb, TCA_OPTIONS);
+	if (opts == NULL)
+		goto nla_put_failure;
+	NLA_PUT_U16(skb, TCA_DSMARK_INDICES, p->indices);
+
+	if (p->default_index != NO_DEFAULT_INDEX)
+		NLA_PUT_U16(skb, TCA_DSMARK_DEFAULT_INDEX, p->default_index);
+
+	if (p->set_tc_index)
+		NLA_PUT_FLAG(skb, TCA_DSMARK_SET_TC_INDEX);
+
+	return nla_nest_end(skb, opts);
+
+nla_put_failure:
+	nla_nest_cancel(skb, opts);
+	return -EMSGSIZE;
+}
+
+static const struct Qdisc_class_ops dsmark_class_ops = {
+	.graft		=	dsmark_graft,
+	.leaf		=	dsmark_leaf,
+	.get		=	dsmark_get,
+	.put		=	dsmark_put,
+	.change		=	dsmark_change,
+	.delete		=	dsmark_delete,
+	.walk		=	dsmark_walk,
+	.tcf_chain	=	dsmark_find_tcf,
+	.bind_tcf	=	dsmark_bind_filter,
+	.unbind_tcf	=	dsmark_put,
+	.dump		=	dsmark_dump_class,
+};
+
+static struct Qdisc_ops dsmark_qdisc_ops __read_mostly = {
+	.next		=	NULL,
+	.cl_ops		=	&dsmark_class_ops,
+	.id		=	"dsmark",
+	.priv_size	=	sizeof(struct dsmark_qdisc_data),
+	.enqueue	=	dsmark_enqueue,
+	.dequeue	=	dsmark_dequeue,
+	.requeue	=	dsmark_requeue,
+	.drop		=	dsmark_drop,
+	.init		=	dsmark_init,
+	.reset		=	dsmark_reset,
+	.destroy	=	dsmark_destroy,
+	.change		=	NULL,
+	.dump		=	dsmark_dump,
+	.owner		=	THIS_MODULE,
+};
+
+static int __init dsmark_module_init(void)
+{
+	return register_qdisc(&dsmark_qdisc_ops);
+}
+
+static void __exit dsmark_module_exit(void)
+{
+	unregister_qdisc(&dsmark_qdisc_ops);
+}
+
+module_init(dsmark_module_init)
+module_exit(dsmark_module_exit)
+
+MODULE_LICENSE("GPL");