--- /dev/null
+/* 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/slab.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 __rcu *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("%s(sch %p,[qdisc %p],new %p,old %p)\n",
+ __func__, sch, p, new, old);
+
+ if (new == NULL) {
+ new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
+ sch->handle);
+ if (new == NULL)
+ new = &noop_qdisc;
+ }
+
+ sch_tree_lock(sch);
+ *old = p->q;
+ 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("%s(sch %p,[qdisc %p],classid %x)\n",
+ __func__, 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("%s(sch %p,[qdisc %p],classid %x,parent %x), arg 0x%lx\n",
+ __func__, 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("%s(sch %p,[qdisc %p],walker %p)\n",
+ __func__, 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 __rcu **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("%s(skb %p,sch %p,[qdisc %p])\n", __func__, skb, sch, p);
+
+ if (p->set_tc_index) {
+ switch (tc_skb_protocol(skb)) {
+ 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;
+ struct tcf_proto *fl = rcu_dereference_bh(p->filter_list);
+ int result = tc_classify(skb, fl, &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))
+ qdisc_qstats_drop(sch);
+ return err;
+ }
+
+ sch->q.qlen++;
+
+ return NET_XMIT_SUCCESS;
+
+drop:
+ qdisc_drop(skb, sch);
+ 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("%s(sch %p,[qdisc %p])\n", __func__, sch, p);
+
+ skb = p->q->ops->dequeue(p->q);
+ if (skb == NULL)
+ return NULL;
+
+ qdisc_bstats_update(sch, skb);
+ sch->q.qlen--;
+
+ index = skb->tc_index & (p->indices - 1);
+ pr_debug("index %d->%d\n", skb->tc_index, index);
+
+ switch (tc_skb_protocol(skb)) {
+ 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])
+ pr_warn("%s: unsupported protocol %d\n",
+ __func__, ntohs(tc_skb_protocol(skb)));
+ break;
+ }
+
+ return skb;
+}
+
+static struct sk_buff *dsmark_peek(struct Qdisc *sch)
+{
+ struct dsmark_qdisc_data *p = qdisc_priv(sch);
+
+ pr_debug("%s(sch %p,[qdisc %p])\n", __func__, sch, p);
+
+ return p->q->ops->peek(p->q);
+}
+
+static unsigned int dsmark_drop(struct Qdisc *sch)
+{
+ struct dsmark_qdisc_data *p = qdisc_priv(sch);
+ unsigned int len;
+
+ pr_debug("%s(sch %p,[qdisc %p])\n", __func__, 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("%s(sch %p,[qdisc %p],opt %p)\n", __func__, 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(sch->dev_queue, &pfifo_qdisc_ops, sch->handle);
+ if (p->q == NULL)
+ p->q = &noop_qdisc;
+
+ pr_debug("%s: qdisc %p\n", __func__, p->q);
+
+ err = 0;
+errout:
+ return err;
+}
+
+static void dsmark_reset(struct Qdisc *sch)
+{
+ struct dsmark_qdisc_data *p = qdisc_priv(sch);
+
+ pr_debug("%s(sch %p,[qdisc %p])\n", __func__, 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("%s(sch %p,[qdisc %p])\n", __func__, 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("%s(sch %p,[qdisc %p],class %ld\n", __func__, 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;
+ if (nla_put_u8(skb, TCA_DSMARK_MASK, p->mask[cl - 1]) ||
+ nla_put_u8(skb, TCA_DSMARK_VALUE, p->value[cl - 1]))
+ goto nla_put_failure;
+
+ 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;
+ if (nla_put_u16(skb, TCA_DSMARK_INDICES, p->indices))
+ goto nla_put_failure;
+
+ if (p->default_index != NO_DEFAULT_INDEX &&
+ nla_put_u16(skb, TCA_DSMARK_DEFAULT_INDEX, p->default_index))
+ goto nla_put_failure;
+
+ if (p->set_tc_index &&
+ nla_put_flag(skb, TCA_DSMARK_SET_TC_INDEX))
+ goto nla_put_failure;
+
+ 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,
+ .peek = dsmark_peek,
+ .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");
Code Review / kvmfornfv.git / blobdiff