Merge tag 'v3.10.87' into update

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / sched / sch_api.c

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 2b935e7cfe7b7bbb78c3cc914a39929f1db766a8..e87b27c7bffd6e469afebc45d48c3a972426bbb7 100644 (file)
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -285,28 +285,70 @@ static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
        return q;
 }
 
+/* The linklayer setting were not transferred from iproute2, in older
+ * versions, and the rate tables lookup systems have been dropped in
+ * the kernel. To keep backward compatible with older iproute2 tc
+ * utils, we detect the linklayer setting by detecting if the rate
+ * table were modified.
+ *
+ * For linklayer ATM table entries, the rate table will be aligned to
+ * 48 bytes, thus some table entries will contain the same value.  The
+ * mpu (min packet unit) is also encoded into the old rate table, thus
+ * starting from the mpu, we find low and high table entries for
+ * mapping this cell.  If these entries contain the same value, when
+ * the rate tables have been modified for linklayer ATM.
+ *
+ * This is done by rounding mpu to the nearest 48 bytes cell/entry,
+ * and then roundup to the next cell, calc the table entry one below,
+ * and compare.
+ */
+static __u8 __detect_linklayer(struct tc_ratespec *r, __u32 *rtab)
+{
+       int low       = roundup(r->mpu, 48);
+       int high      = roundup(low+1, 48);
+       int cell_low  = low >> r->cell_log;
+       int cell_high = (high >> r->cell_log) - 1;
+
+       /* rtab is too inaccurate at rates > 100Mbit/s */
+       if ((r->rate > (100000000/8)) || (rtab[0] == 0)) {
+               pr_debug("TC linklayer: Giving up ATM detection\n");
+               return TC_LINKLAYER_ETHERNET;
+       }
+
+       if ((cell_high > cell_low) && (cell_high < 256)
+           && (rtab[cell_low] == rtab[cell_high])) {
+               pr_debug("TC linklayer: Detected ATM, low(%d)=high(%d)=%u\n",
+                        cell_low, cell_high, rtab[cell_high]);
+               return TC_LINKLAYER_ATM;
+       }
+       return TC_LINKLAYER_ETHERNET;
+}
+
 static struct qdisc_rate_table *qdisc_rtab_list;
 
 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab)
 {
        struct qdisc_rate_table *rtab;
 
+       if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
+           nla_len(tab) != TC_RTAB_SIZE)
+               return NULL;
+
        for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
-               if (memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) == 0) {
+               if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) &&
+                   !memcmp(&rtab->data, nla_data(tab), 1024)) {
                        rtab->refcnt++;
                        return rtab;
                }
        }
 
-       if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
-           nla_len(tab) != TC_RTAB_SIZE)
-               return NULL;
-
        rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
        if (rtab) {
                rtab->rate = *r;
                rtab->refcnt = 1;
                memcpy(rtab->data, nla_data(tab), 1024);
+               if (r->linklayer == TC_LINKLAYER_UNAWARE)
+                       r->linklayer = __detect_linklayer(r, rtab->data);
                rtab->next = qdisc_rtab_list;
                qdisc_rtab_list = rtab;
        }
@@ -710,10 +752,8 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
                if (dev->flags & IFF_UP)
                        dev_deactivate(dev);
 
-               if (new && new->ops->attach) {
-                       new->ops->attach(new);
-                       num_q = 0;
-               }
+               if (new && new->ops->attach)
+                       goto skip;
 
                for (i = 0; i < num_q; i++) {
                        struct netdev_queue *dev_queue = dev_ingress_queue(dev);
@@ -729,12 +769,16 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
                                qdisc_destroy(old);
                }
 
+skip:
                if (!ingress) {
                        notify_and_destroy(net, skb, n, classid,
                                           dev->qdisc, new);
                        if (new && !new->ops->attach)
                                atomic_inc(&new->refcnt);
                        dev->qdisc = new ? : &noop_qdisc;
+
+                       if (new && new->ops->attach)
+                               new->ops->attach(new);
                } else {
                        notify_and_destroy(net, skb, n, classid, old, new);
                }
@@ -982,7 +1026,7 @@ static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
        struct Qdisc *p = NULL;
        int err;
 
-       if ((n->nlmsg_type != RTM_GETQDISC) && !capable(CAP_NET_ADMIN))
+       if ((n->nlmsg_type != RTM_GETQDISC) && !netlink_capable(skb, CAP_NET_ADMIN))
                return -EPERM;
 
        err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
@@ -1049,7 +1093,7 @@ static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
        struct Qdisc *q, *p;
        int err;
 
-       if (!capable(CAP_NET_ADMIN))
+       if (!netlink_capable(skb, CAP_NET_ADMIN))
                return -EPERM;
 
 replay:
@@ -1389,7 +1433,7 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
        u32 qid;
        int err;
 
-       if ((n->nlmsg_type != RTM_GETTCLASS) && !capable(CAP_NET_ADMIN))
+       if ((n->nlmsg_type != RTM_GETTCLASS) && !netlink_capable(skb, CAP_NET_ADMIN))
                return -EPERM;
 
        err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);