Linux-2.6.12-rc2v2.6.12-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!

1 files changed, 630 insertions, 0 deletions

diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c
new file mode 100644
index 000000000000..25c171c32715
--- /dev/null
+++ b/net/sched/sch_gred.c
@@ -0,0 +1,630 @@
+/*
+ * net/sched/sch_gred.c Generic Random Early Detection queue.
+ *
+ *
+ *              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:    J Hadi Salim (hadi@cyberus.ca) 1998-2002
+ *
+ *             991129: -  Bug fix with grio mode
+ *                     - a better sing. AvgQ mode with Grio(WRED)
+ *                     - A finer grained VQ dequeue based on sugestion
+ *                       from Ren Liu
+ *                     - More error checks
+ *
+ *
+ *
+ *  For all the glorious comments look at Alexey's sch_red.c
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/bitops.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/if_ether.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/notifier.h>
+#include <net/ip.h>
+#include <net/route.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+
+#if 1 /* control */
+#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
+#else
+#define DPRINTK(format,args...)
+#endif
+
+#if 0 /* data */
+#define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
+#else
+#define D2PRINTK(format,args...)
+#endif
+
+struct gred_sched_data;
+struct gred_sched;
+
+struct gred_sched_data
+{
+/* Parameters */
+        u32             limit;          /* HARD maximal queue length    */
+        u32             qth_min;        /* Min average length threshold: A scaled */
+        u32             qth_max;        /* Max average length threshold: A scaled */
+        u32             DP;             /* the drop pramaters */
+        char            Wlog;           /* log(W)               */
+        char            Plog;           /* random number bits   */
+        u32             Scell_max;
+        u32             Rmask;
+        u32             bytesin;        /* bytes seen on virtualQ so far*/
+        u32             packetsin;      /* packets seen on virtualQ so far*/
+        u32             backlog;        /* bytes on the virtualQ */
+        u32             forced; /* packets dropped for exceeding limits */
+        u32             early;  /* packets dropped as a warning */
+        u32             other;  /* packets dropped by invoking drop() */
+        u32             pdrop;  /* packets dropped because we exceeded physical queue limits */
+        char            Scell_log;
+        u8              Stab[256];
+        u8              prio;        /* the prio of this vq */
+
+/* Variables */
+        unsigned long   qave;           /* Average queue length: A scaled */
+        int             qcount;         /* Packets since last random number generation */
+        u32             qR;             /* Cached random number */
+
+        psched_time_t   qidlestart;     /* Start of idle period */
+};
+
+struct gred_sched
+{
+        struct gred_sched_data *tab[MAX_DPs];
+        u32             DPs;   
+        u32             def; 
+        u8              initd; 
+        u8              grio; 
+        u8              eqp; 
+};
+
+static int
+gred_enqueue(struct sk_buff *skb, struct Qdisc* sch)
+{
+        psched_time_t now;
+        struct gred_sched_data *q=NULL;
+        struct gred_sched *t= qdisc_priv(sch);
+        unsigned long   qave=0; 
+        int i=0;
+
+        if (!t->initd && skb_queue_len(&sch->q) < (sch->dev->tx_queue_len ? : 1)) {
+                D2PRINTK("NO GRED Queues setup yet! Enqueued anyway\n");
+                goto do_enqueue;
+        }
+
+
+        if ( ((skb->tc_index&0xf) > (t->DPs -1)) || !(q=t->tab[skb->tc_index&0xf])) {
+                printk("GRED: setting to default (%d)\n ",t->def);
+                if (!(q=t->tab[t->def])) {
+                        DPRINTK("GRED: setting to default FAILED! dropping!! "
+                            "(%d)\n ", t->def);
+                        goto drop;
+                }
+                /* fix tc_index? --could be controvesial but needed for
+                   requeueing */
+                skb->tc_index=(skb->tc_index&0xfffffff0) | t->def;
+        }
+
+        D2PRINTK("gred_enqueue virtualQ 0x%x classid %x backlog %d "
+            "general backlog %d\n",skb->tc_index&0xf,sch->handle,q->backlog,
+            sch->qstats.backlog);
+        /* sum up all the qaves of prios <= to ours to get the new qave*/
+        if (!t->eqp && t->grio) {
+                for (i=0;i<t->DPs;i++) {
+                        if ((!t->tab[i]) || (i==q->DP)) 
+                                continue; 
+                                
+                        if ((t->tab[i]->prio < q->prio) && (PSCHED_IS_PASTPERFECT(t->tab[i]->qidlestart)))
+                                qave +=t->tab[i]->qave;
+                }
+                        
+        }
+
+        q->packetsin++;
+        q->bytesin+=skb->len;
+
+        if (t->eqp && t->grio) {
+                qave=0;
+                q->qave=t->tab[t->def]->qave;
+                q->qidlestart=t->tab[t->def]->qidlestart;
+        }
+
+        if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
+                long us_idle;
+                PSCHED_GET_TIME(now);
+                us_idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
+                PSCHED_SET_PASTPERFECT(q->qidlestart);
+
+                q->qave >>= q->Stab[(us_idle>>q->Scell_log)&0xFF];
+        } else {
+                if (t->eqp) {
+                        q->qave += sch->qstats.backlog - (q->qave >> q->Wlog);
+                } else {
+                        q->qave += q->backlog - (q->qave >> q->Wlog);
+                }
+
+        }
+        
+
+        if (t->eqp && t->grio) 
+                t->tab[t->def]->qave=q->qave;
+
+        if ((q->qave+qave) < q->qth_min) {
+                q->qcount = -1;
+enqueue:
+                if (q->backlog + skb->len <= q->limit) {
+                        q->backlog += skb->len;
+do_enqueue:
+                        __skb_queue_tail(&sch->q, skb);
+                        sch->qstats.backlog += skb->len;
+                        sch->bstats.bytes += skb->len;
+                        sch->bstats.packets++;
+                        return 0;
+                } else {
+                        q->pdrop++;
+                }
+
+drop:
+                kfree_skb(skb);
+                sch->qstats.drops++;
+                return NET_XMIT_DROP;
+        }
+        if ((q->qave+qave) >= q->qth_max) {
+                q->qcount = -1;
+                sch->qstats.overlimits++;
+                q->forced++;
+                goto drop;
+        }
+        if (++q->qcount) {
+                if ((((qave+q->qave) - q->qth_min)>>q->Wlog)*q->qcount < q->qR)
+                        goto enqueue;
+                q->qcount = 0;
+                q->qR = net_random()&q->Rmask;
+                sch->qstats.overlimits++;
+                q->early++;
+                goto drop;
+        }
+        q->qR = net_random()&q->Rmask;
+        goto enqueue;
+}
+
+static int
+gred_requeue(struct sk_buff *skb, struct Qdisc* sch)
+{
+        struct gred_sched_data *q;
+        struct gred_sched *t= qdisc_priv(sch);
+        q= t->tab[(skb->tc_index&0xf)];
+/* error checking here -- probably unnecessary */
+        PSCHED_SET_PASTPERFECT(q->qidlestart);
+
+        __skb_queue_head(&sch->q, skb);
+        sch->qstats.backlog += skb->len;
+        sch->qstats.requeues++;
+        q->backlog += skb->len;
+        return 0;
+}
+
+static struct sk_buff *
+gred_dequeue(struct Qdisc* sch)
+{
+        struct sk_buff *skb;
+        struct gred_sched_data *q;
+        struct gred_sched *t= qdisc_priv(sch);
+
+        skb = __skb_dequeue(&sch->q);
+        if (skb) {
+                sch->qstats.backlog -= skb->len;
+                q= t->tab[(skb->tc_index&0xf)];
+                if (q) {
+                        q->backlog -= skb->len;
+                        if (!q->backlog && !t->eqp)
+                                PSCHED_GET_TIME(q->qidlestart);
+                } else {
+                        D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf); 
+                }
+                return skb;
+        }
+
+        if (t->eqp) {
+                        q= t->tab[t->def];
+                        if (!q) 
+                                D2PRINTK("no default VQ set: Results will be "
+                                       "screwed up\n");
+                        else
+                                PSCHED_GET_TIME(q->qidlestart);
+        }
+
+        return NULL;
+}
+
+static unsigned int gred_drop(struct Qdisc* sch)
+{
+        struct sk_buff *skb;
+
+        struct gred_sched_data *q;
+        struct gred_sched *t= qdisc_priv(sch);
+
+        skb = __skb_dequeue_tail(&sch->q);
+        if (skb) {
+                unsigned int len = skb->len;
+                sch->qstats.backlog -= len;
+                sch->qstats.drops++;
+                q= t->tab[(skb->tc_index&0xf)];
+                if (q) {
+                        q->backlog -= len;
+                        q->other++;
+                        if (!q->backlog && !t->eqp)
+                                PSCHED_GET_TIME(q->qidlestart);
+                } else {
+                        D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf); 
+                }
+
+                kfree_skb(skb);
+                return len;
+        }
+
+        q=t->tab[t->def];
+        if (!q) {
+                D2PRINTK("no default VQ set: Results might be screwed up\n");
+                return 0;
+        }
+
+        PSCHED_GET_TIME(q->qidlestart);
+        return 0;
+
+}
+
+static void gred_reset(struct Qdisc* sch)
+{
+        int i;
+        struct gred_sched_data *q;
+        struct gred_sched *t= qdisc_priv(sch);
+
+        __skb_queue_purge(&sch->q);
+
+        sch->qstats.backlog = 0;
+
+        for (i=0;i<t->DPs;i++) {
+                q= t->tab[i];
+                if (!q) 
+                        continue; 
+                PSCHED_SET_PASTPERFECT(q->qidlestart);
+                q->qave = 0;
+                q->qcount = -1;
+                q->backlog = 0;
+                q->other=0;
+                q->forced=0;
+                q->pdrop=0;
+                q->early=0;
+        }
+}
+
+static int gred_change(struct Qdisc *sch, struct rtattr *opt)
+{
+        struct gred_sched *table = qdisc_priv(sch);
+        struct gred_sched_data *q;
+        struct tc_gred_qopt *ctl;
+        struct tc_gred_sopt *sopt;
+        struct rtattr *tb[TCA_GRED_STAB];
+        struct rtattr *tb2[TCA_GRED_DPS];
+        int i;
+
+        if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
+                return -EINVAL;
+
+        if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
+                rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
+
+            if (tb2[TCA_GRED_DPS-1] == 0) 
+                        return -EINVAL;
+
+                sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
+                table->DPs=sopt->DPs;   
+                table->def=sopt->def_DP; 
+                table->grio=sopt->grio; 
+                table->initd=0;
+                /* probably need to clear all the table DP entries as well */
+                return 0;
+            }
+
+
+        if (!table->DPs || tb[TCA_GRED_PARMS-1] == 0 || tb[TCA_GRED_STAB-1] == 0 ||
+                RTA_PAYLOAD(tb[TCA_GRED_PARMS-1]) < sizeof(*ctl) ||
+                RTA_PAYLOAD(tb[TCA_GRED_STAB-1]) < 256)
+                        return -EINVAL;
+
+        ctl = RTA_DATA(tb[TCA_GRED_PARMS-1]);
+        if (ctl->DP > MAX_DPs-1 ) {
+                /* misbehaving is punished! Put in the default drop probability */
+                DPRINTK("\nGRED: DP %u not in  the proper range fixed. New DP "
+                        "set to default at %d\n",ctl->DP,table->def);
+                ctl->DP=table->def;
+        }
+        
+        if (table->tab[ctl->DP] == NULL) {
+                table->tab[ctl->DP]=kmalloc(sizeof(struct gred_sched_data),
+                                            GFP_KERNEL);
+                if (NULL == table->tab[ctl->DP])
+                        return -ENOMEM;
+                memset(table->tab[ctl->DP], 0, (sizeof(struct gred_sched_data)));
+        }
+        q= table->tab[ctl->DP]; 
+
+        if (table->grio) {
+                if (ctl->prio <=0) {
+                        if (table->def && table->tab[table->def]) {
+                                DPRINTK("\nGRED: DP %u does not have a prio"
+                                        "setting default to %d\n",ctl->DP,
+                                        table->tab[table->def]->prio);
+                                q->prio=table->tab[table->def]->prio;
+                        } else { 
+                                DPRINTK("\nGRED: DP %u does not have a prio"
+                                        " setting default to 8\n",ctl->DP);
+                                q->prio=8;
+                        }
+                } else {
+                        q->prio=ctl->prio;
+                }
+        } else {
+                q->prio=8;
+        }
+
+
+        q->DP=ctl->DP;
+        q->Wlog = ctl->Wlog;
+        q->Plog = ctl->Plog;
+        q->limit = ctl->limit;
+        q->Scell_log = ctl->Scell_log;
+        q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
+        q->Scell_max = (255<<q->Scell_log);
+        q->qth_min = ctl->qth_min<<ctl->Wlog;
+        q->qth_max = ctl->qth_max<<ctl->Wlog;
+        q->qave=0;
+        q->backlog=0;
+        q->qcount = -1;
+        q->other=0;
+        q->forced=0;
+        q->pdrop=0;
+        q->early=0;
+
+        PSCHED_SET_PASTPERFECT(q->qidlestart);
+        memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
+
+        if ( table->initd && table->grio) {
+        /* this looks ugly but it's not in the fast path */
+                for (i=0;i<table->DPs;i++) {
+                        if ((!table->tab[i]) || (i==q->DP) )    
+                                continue; 
+                        if (table->tab[i]->prio == q->prio ){
+                                /* WRED mode detected */
+                                table->eqp=1;
+                                break;
+                        }
+                }
+        }
+
+        if (!table->initd) {
+                table->initd=1;
+                /* 
+                the first entry also goes into the default until
+                over-written 
+                */
+
+                if (table->tab[table->def] == NULL) {
+                        table->tab[table->def]=
+                                kmalloc(sizeof(struct gred_sched_data), GFP_KERNEL);
+                        if (NULL == table->tab[table->def])
+                                return -ENOMEM;
+
+                        memset(table->tab[table->def], 0,
+                               (sizeof(struct gred_sched_data)));
+                }
+                q= table->tab[table->def]; 
+                q->DP=table->def;
+                q->Wlog = ctl->Wlog;
+                q->Plog = ctl->Plog;
+                q->limit = ctl->limit;
+                q->Scell_log = ctl->Scell_log;
+                q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
+                q->Scell_max = (255<<q->Scell_log);
+                q->qth_min = ctl->qth_min<<ctl->Wlog;
+                q->qth_max = ctl->qth_max<<ctl->Wlog;
+
+                if (table->grio)
+                        q->prio=table->tab[ctl->DP]->prio;
+                else
+                        q->prio=8;
+
+                q->qcount = -1;
+                PSCHED_SET_PASTPERFECT(q->qidlestart);
+                memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
+        }
+        return 0;
+
+}
+
+static int gred_init(struct Qdisc *sch, struct rtattr *opt)
+{
+        struct gred_sched *table = qdisc_priv(sch);
+        struct tc_gred_sopt *sopt;
+        struct rtattr *tb[TCA_GRED_STAB];
+        struct rtattr *tb2[TCA_GRED_DPS];
+
+        if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
+                return -EINVAL;
+
+        if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
+                rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
+
+            if (tb2[TCA_GRED_DPS-1] == 0) 
+                        return -EINVAL;
+
+                sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
+                table->DPs=sopt->DPs;   
+                table->def=sopt->def_DP; 
+                table->grio=sopt->grio; 
+                table->initd=0;
+                return 0;
+        }
+
+        DPRINTK("\n GRED_INIT error!\n");
+        return -EINVAL;
+}
+
+static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+        unsigned long qave;
+        struct rtattr *rta;
+        struct tc_gred_qopt *opt = NULL ;
+        struct tc_gred_qopt *dst;
+        struct gred_sched *table = qdisc_priv(sch);
+        struct gred_sched_data *q;
+        int i;
+        unsigned char    *b = skb->tail;
+
+        rta = (struct rtattr*)b;
+        RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
+
+        opt=kmalloc(sizeof(struct tc_gred_qopt)*MAX_DPs, GFP_KERNEL);
+
+        if (opt  == NULL) {
+                DPRINTK("gred_dump:failed to malloc for %Zd\n",
+                    sizeof(struct tc_gred_qopt)*MAX_DPs);
+                goto rtattr_failure;
+        }
+
+        memset(opt, 0, (sizeof(struct tc_gred_qopt))*table->DPs);
+
+        if (!table->initd) {
+                DPRINTK("NO GRED Queues setup!\n");
+        }
+
+        for (i=0;i<MAX_DPs;i++) {
+                dst= &opt[i]; 
+                q= table->tab[i]; 
+
+                if (!q) {
+                        /* hack -- fix at some point with proper message
+                           This is how we indicate to tc that there is no VQ
+                           at this DP */
+
+                        dst->DP=MAX_DPs+i;
+                        continue;
+                }
+
+                dst->limit=q->limit;
+                dst->qth_min=q->qth_min>>q->Wlog;
+                dst->qth_max=q->qth_max>>q->Wlog;
+                dst->DP=q->DP;
+                dst->backlog=q->backlog;
+                if (q->qave) {
+                        if (table->eqp && table->grio) {
+                                q->qidlestart=table->tab[table->def]->qidlestart;
+                                q->qave=table->tab[table->def]->qave;
+                        }
+                        if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
+                                long idle;
+                                psched_time_t now;
+                                PSCHED_GET_TIME(now);
+                                idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
+                                qave  = q->qave >> q->Stab[(idle>>q->Scell_log)&0xFF];
+                                dst->qave = qave >> q->Wlog;
+
+                        } else {
+                                dst->qave = q->qave >> q->Wlog;
+                        }
+                } else {
+                        dst->qave = 0;
+                }
+                
+
+                dst->Wlog = q->Wlog;
+                dst->Plog = q->Plog;
+                dst->Scell_log = q->Scell_log;
+                dst->other = q->other;
+                dst->forced = q->forced;
+                dst->early = q->early;
+                dst->pdrop = q->pdrop;
+                dst->prio = q->prio;
+                dst->packets=q->packetsin;
+                dst->bytesin=q->bytesin;
+        }
+
+        RTA_PUT(skb, TCA_GRED_PARMS, sizeof(struct tc_gred_qopt)*MAX_DPs, opt);
+        rta->rta_len = skb->tail - b;
+
+        kfree(opt);
+        return skb->len;
+
+rtattr_failure:
+        if (opt)
+                kfree(opt);
+        DPRINTK("gred_dump: FAILURE!!!!\n");
+
+/* also free the opt struct here */
+        skb_trim(skb, b - skb->data);
+        return -1;
+}
+
+static void gred_destroy(struct Qdisc *sch)
+{
+        struct gred_sched *table = qdisc_priv(sch);
+        int i;
+
+        for (i = 0;i < table->DPs; i++) {
+                if (table->tab[i])
+                        kfree(table->tab[i]);
+        }
+}
+
+static struct Qdisc_ops gred_qdisc_ops = {
+        .next           =       NULL,
+        .cl_ops         =       NULL,
+        .id             =       "gred",
+        .priv_size      =       sizeof(struct gred_sched),
+        .enqueue        =       gred_enqueue,
+        .dequeue        =       gred_dequeue,
+        .requeue        =       gred_requeue,
+        .drop           =       gred_drop,
+        .init           =       gred_init,
+        .reset          =       gred_reset,
+        .destroy        =       gred_destroy,
+        .change         =       gred_change,
+        .dump           =       gred_dump,
+        .owner          =       THIS_MODULE,
+};
+
+static int __init gred_module_init(void)
+{
+        return register_qdisc(&gred_qdisc_ops);
+}
+static void __exit gred_module_exit(void) 
+{
+        unregister_qdisc(&gred_qdisc_ops);
+}
+module_init(gred_module_init)
+module_exit(gred_module_exit)
+MODULE_LICENSE("GPL");