| /* 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(sch->dev, 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 __constant_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 __constant_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; |
| |
| 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 = p->q->enqueue(skb, p->q); |
| if (err != NET_XMIT_SUCCESS) { |
| sch->qstats.drops++; |
| return err; |
| } |
| |
| sch->bstats.bytes += skb->len; |
| sch->bstats.packets++; |
| sch->q.qlen++; |
| |
| return NET_XMIT_SUCCESS; |
| |
| drop: |
| kfree_skb(skb); |
| sch->qstats.drops++; |
| return 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 __constant_htons(ETH_P_IP): |
| ipv4_change_dsfield(ip_hdr(skb), p->mask[index], |
| p->value[index]); |
| break; |
| case __constant_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) { |
| 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(sch->dev, 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"); |