Merge branch 'for-linus' of git://git.kernel.dk/linux-block
[firefly-linux-kernel-4.4.55.git] / net / sched / act_bpf.c
index 5f6288fa3f1247462897cd747364dfbc9e0da843..dc6a2d324bd8163841e7c9e6a0defebd87792ae5 100644 (file)
 #include <linux/skbuff.h>
 #include <linux/rtnetlink.h>
 #include <linux/filter.h>
+#include <linux/bpf.h>
+
 #include <net/netlink.h>
 #include <net/pkt_sched.h>
 
 #include <linux/tc_act/tc_bpf.h>
 #include <net/tc_act/tc_bpf.h>
 
-#define BPF_TAB_MASK     15
+#define BPF_TAB_MASK           15
+#define ACT_BPF_NAME_LEN       256
+
+struct tcf_bpf_cfg {
+       struct bpf_prog *filter;
+       struct sock_filter *bpf_ops;
+       char *bpf_name;
+       u32 bpf_fd;
+       u16 bpf_num_ops;
+};
 
-static int tcf_bpf(struct sk_buff *skb, const struct tc_action *a,
+static int tcf_bpf(struct sk_buff *skb, const struct tc_action *act,
                   struct tcf_result *res)
 {
-       struct tcf_bpf *b = a->priv;
+       struct tcf_bpf *prog = act->priv;
        int action, filter_res;
 
-       spin_lock(&b->tcf_lock);
+       if (unlikely(!skb_mac_header_was_set(skb)))
+               return TC_ACT_UNSPEC;
+
+       spin_lock(&prog->tcf_lock);
 
-       b->tcf_tm.lastuse = jiffies;
-       bstats_update(&b->tcf_bstats, skb);
+       prog->tcf_tm.lastuse = jiffies;
+       bstats_update(&prog->tcf_bstats, skb);
 
-       filter_res = BPF_PROG_RUN(b->filter, skb);
+       /* Needed here for accessing maps. */
+       rcu_read_lock();
+       filter_res = BPF_PROG_RUN(prog->filter, skb);
+       rcu_read_unlock();
 
        /* A BPF program may overwrite the default action opcode.
         * Similarly as in cls_bpf, if filter_res == -1 we use the
@@ -52,52 +69,87 @@ static int tcf_bpf(struct sk_buff *skb, const struct tc_action *a,
                break;
        case TC_ACT_SHOT:
                action = filter_res;
-               b->tcf_qstats.drops++;
+               prog->tcf_qstats.drops++;
                break;
        case TC_ACT_UNSPEC:
-               action = b->tcf_action;
+               action = prog->tcf_action;
                break;
        default:
                action = TC_ACT_UNSPEC;
                break;
        }
 
-       spin_unlock(&b->tcf_lock);
+       spin_unlock(&prog->tcf_lock);
        return action;
 }
 
-static int tcf_bpf_dump(struct sk_buff *skb, struct tc_action *a,
+static bool tcf_bpf_is_ebpf(const struct tcf_bpf *prog)
+{
+       return !prog->bpf_ops;
+}
+
+static int tcf_bpf_dump_bpf_info(const struct tcf_bpf *prog,
+                                struct sk_buff *skb)
+{
+       struct nlattr *nla;
+
+       if (nla_put_u16(skb, TCA_ACT_BPF_OPS_LEN, prog->bpf_num_ops))
+               return -EMSGSIZE;
+
+       nla = nla_reserve(skb, TCA_ACT_BPF_OPS, prog->bpf_num_ops *
+                         sizeof(struct sock_filter));
+       if (nla == NULL)
+               return -EMSGSIZE;
+
+       memcpy(nla_data(nla), prog->bpf_ops, nla_len(nla));
+
+       return 0;
+}
+
+static int tcf_bpf_dump_ebpf_info(const struct tcf_bpf *prog,
+                                 struct sk_buff *skb)
+{
+       if (nla_put_u32(skb, TCA_ACT_BPF_FD, prog->bpf_fd))
+               return -EMSGSIZE;
+
+       if (prog->bpf_name &&
+           nla_put_string(skb, TCA_ACT_BPF_NAME, prog->bpf_name))
+               return -EMSGSIZE;
+
+       return 0;
+}
+
+static int tcf_bpf_dump(struct sk_buff *skb, struct tc_action *act,
                        int bind, int ref)
 {
        unsigned char *tp = skb_tail_pointer(skb);
-       struct tcf_bpf *b = a->priv;
+       struct tcf_bpf *prog = act->priv;
        struct tc_act_bpf opt = {
-               .index    = b->tcf_index,
-               .refcnt   = b->tcf_refcnt - ref,
-               .bindcnt  = b->tcf_bindcnt - bind,
-               .action   = b->tcf_action,
+               .index   = prog->tcf_index,
+               .refcnt  = prog->tcf_refcnt - ref,
+               .bindcnt = prog->tcf_bindcnt - bind,
+               .action  = prog->tcf_action,
        };
-       struct tcf_t t;
-       struct nlattr *nla;
+       struct tcf_t tm;
+       int ret;
 
        if (nla_put(skb, TCA_ACT_BPF_PARMS, sizeof(opt), &opt))
                goto nla_put_failure;
 
-       if (nla_put_u16(skb, TCA_ACT_BPF_OPS_LEN, b->bpf_num_ops))
-               goto nla_put_failure;
-
-       nla = nla_reserve(skb, TCA_ACT_BPF_OPS, b->bpf_num_ops *
-                         sizeof(struct sock_filter));
-       if (!nla)
+       if (tcf_bpf_is_ebpf(prog))
+               ret = tcf_bpf_dump_ebpf_info(prog, skb);
+       else
+               ret = tcf_bpf_dump_bpf_info(prog, skb);
+       if (ret)
                goto nla_put_failure;
 
-       memcpy(nla_data(nla), b->bpf_ops, nla_len(nla));
+       tm.install = jiffies_to_clock_t(jiffies - prog->tcf_tm.install);
+       tm.lastuse = jiffies_to_clock_t(jiffies - prog->tcf_tm.lastuse);
+       tm.expires = jiffies_to_clock_t(prog->tcf_tm.expires);
 
-       t.install = jiffies_to_clock_t(jiffies - b->tcf_tm.install);
-       t.lastuse = jiffies_to_clock_t(jiffies - b->tcf_tm.lastuse);
-       t.expires = jiffies_to_clock_t(b->tcf_tm.expires);
-       if (nla_put(skb, TCA_ACT_BPF_TM, sizeof(t), &t))
+       if (nla_put(skb, TCA_ACT_BPF_TM, sizeof(tm), &tm))
                goto nla_put_failure;
+
        return skb->len;
 
 nla_put_failure:
@@ -107,36 +159,21 @@ nla_put_failure:
 
 static const struct nla_policy act_bpf_policy[TCA_ACT_BPF_MAX + 1] = {
        [TCA_ACT_BPF_PARMS]     = { .len = sizeof(struct tc_act_bpf) },
+       [TCA_ACT_BPF_FD]        = { .type = NLA_U32 },
+       [TCA_ACT_BPF_NAME]      = { .type = NLA_NUL_STRING, .len = ACT_BPF_NAME_LEN },
        [TCA_ACT_BPF_OPS_LEN]   = { .type = NLA_U16 },
        [TCA_ACT_BPF_OPS]       = { .type = NLA_BINARY,
                                    .len = sizeof(struct sock_filter) * BPF_MAXINSNS },
 };
 
-static int tcf_bpf_init(struct net *net, struct nlattr *nla,
-                       struct nlattr *est, struct tc_action *a,
-                       int ovr, int bind)
+static int tcf_bpf_init_from_ops(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
 {
-       struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
-       struct tc_act_bpf *parm;
-       struct tcf_bpf *b;
-       u16 bpf_size, bpf_num_ops;
        struct sock_filter *bpf_ops;
-       struct sock_fprog_kern tmp;
+       struct sock_fprog_kern fprog_tmp;
        struct bpf_prog *fp;
+       u16 bpf_size, bpf_num_ops;
        int ret;
 
-       if (!nla)
-               return -EINVAL;
-
-       ret = nla_parse_nested(tb, TCA_ACT_BPF_MAX, nla, act_bpf_policy);
-       if (ret < 0)
-               return ret;
-
-       if (!tb[TCA_ACT_BPF_PARMS] ||
-           !tb[TCA_ACT_BPF_OPS_LEN] || !tb[TCA_ACT_BPF_OPS])
-               return -EINVAL;
-       parm = nla_data(tb[TCA_ACT_BPF_PARMS]);
-
        bpf_num_ops = nla_get_u16(tb[TCA_ACT_BPF_OPS_LEN]);
        if (bpf_num_ops > BPF_MAXINSNS || bpf_num_ops == 0)
                return -EINVAL;
@@ -146,68 +183,165 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
                return -EINVAL;
 
        bpf_ops = kzalloc(bpf_size, GFP_KERNEL);
-       if (!bpf_ops)
+       if (bpf_ops == NULL)
                return -ENOMEM;
 
        memcpy(bpf_ops, nla_data(tb[TCA_ACT_BPF_OPS]), bpf_size);
 
-       tmp.len = bpf_num_ops;
-       tmp.filter = bpf_ops;
+       fprog_tmp.len = bpf_num_ops;
+       fprog_tmp.filter = bpf_ops;
 
-       ret = bpf_prog_create(&fp, &tmp);
-       if (ret)
-               goto free_bpf_ops;
+       ret = bpf_prog_create(&fp, &fprog_tmp);
+       if (ret < 0) {
+               kfree(bpf_ops);
+               return ret;
+       }
 
-       if (!tcf_hash_check(parm->index, a, bind)) {
-               ret = tcf_hash_create(parm->index, est, a, sizeof(*b), bind);
-               if (ret)
+       cfg->bpf_ops = bpf_ops;
+       cfg->bpf_num_ops = bpf_num_ops;
+       cfg->filter = fp;
+
+       return 0;
+}
+
+static int tcf_bpf_init_from_efd(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
+{
+       struct bpf_prog *fp;
+       char *name = NULL;
+       u32 bpf_fd;
+
+       bpf_fd = nla_get_u32(tb[TCA_ACT_BPF_FD]);
+
+       fp = bpf_prog_get(bpf_fd);
+       if (IS_ERR(fp))
+               return PTR_ERR(fp);
+
+       if (fp->type != BPF_PROG_TYPE_SCHED_ACT) {
+               bpf_prog_put(fp);
+               return -EINVAL;
+       }
+
+       if (tb[TCA_ACT_BPF_NAME]) {
+               name = kmemdup(nla_data(tb[TCA_ACT_BPF_NAME]),
+                              nla_len(tb[TCA_ACT_BPF_NAME]),
+                              GFP_KERNEL);
+               if (!name) {
+                       bpf_prog_put(fp);
+                       return -ENOMEM;
+               }
+       }
+
+       cfg->bpf_fd = bpf_fd;
+       cfg->bpf_name = name;
+       cfg->filter = fp;
+
+       return 0;
+}
+
+static int tcf_bpf_init(struct net *net, struct nlattr *nla,
+                       struct nlattr *est, struct tc_action *act,
+                       int replace, int bind)
+{
+       struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
+       struct tc_act_bpf *parm;
+       struct tcf_bpf *prog;
+       struct tcf_bpf_cfg cfg;
+       bool is_bpf, is_ebpf;
+       int ret;
+
+       if (!nla)
+               return -EINVAL;
+
+       ret = nla_parse_nested(tb, TCA_ACT_BPF_MAX, nla, act_bpf_policy);
+       if (ret < 0)
+               return ret;
+
+       is_bpf = tb[TCA_ACT_BPF_OPS_LEN] && tb[TCA_ACT_BPF_OPS];
+       is_ebpf = tb[TCA_ACT_BPF_FD];
+
+       if ((!is_bpf && !is_ebpf) || (is_bpf && is_ebpf) ||
+           !tb[TCA_ACT_BPF_PARMS])
+               return -EINVAL;
+
+       parm = nla_data(tb[TCA_ACT_BPF_PARMS]);
+
+       memset(&cfg, 0, sizeof(cfg));
+
+       ret = is_bpf ? tcf_bpf_init_from_ops(tb, &cfg) :
+                      tcf_bpf_init_from_efd(tb, &cfg);
+       if (ret < 0)
+               return ret;
+
+       if (!tcf_hash_check(parm->index, act, bind)) {
+               ret = tcf_hash_create(parm->index, est, act,
+                                     sizeof(*prog), bind);
+               if (ret < 0)
                        goto destroy_fp;
 
                ret = ACT_P_CREATED;
        } else {
+               /* Don't override defaults. */
                if (bind)
                        goto destroy_fp;
-               tcf_hash_release(a, bind);
-               if (!ovr) {
+
+               tcf_hash_release(act, bind);
+               if (!replace) {
                        ret = -EEXIST;
                        goto destroy_fp;
                }
        }
 
-       b = to_bpf(a);
-       spin_lock_bh(&b->tcf_lock);
-       b->tcf_action = parm->action;
-       b->bpf_num_ops = bpf_num_ops;
-       b->bpf_ops = bpf_ops;
-       b->filter = fp;
-       spin_unlock_bh(&b->tcf_lock);
+       prog = to_bpf(act);
+       spin_lock_bh(&prog->tcf_lock);
+
+       prog->bpf_ops = cfg.bpf_ops;
+       prog->bpf_name = cfg.bpf_name;
+
+       if (cfg.bpf_num_ops)
+               prog->bpf_num_ops = cfg.bpf_num_ops;
+       if (cfg.bpf_fd)
+               prog->bpf_fd = cfg.bpf_fd;
+
+       prog->tcf_action = parm->action;
+       prog->filter = cfg.filter;
+
+       spin_unlock_bh(&prog->tcf_lock);
 
        if (ret == ACT_P_CREATED)
-               tcf_hash_insert(a);
+               tcf_hash_insert(act);
+
        return ret;
 
 destroy_fp:
-       bpf_prog_destroy(fp);
-free_bpf_ops:
-       kfree(bpf_ops);
+       if (is_ebpf)
+               bpf_prog_put(cfg.filter);
+       else
+               bpf_prog_destroy(cfg.filter);
+
+       kfree(cfg.bpf_ops);
+       kfree(cfg.bpf_name);
+
        return ret;
 }
 
-static void tcf_bpf_cleanup(struct tc_action *a, int bind)
+static void tcf_bpf_cleanup(struct tc_action *act, int bind)
 {
-       struct tcf_bpf *b = a->priv;
+       const struct tcf_bpf *prog = act->priv;
 
-       bpf_prog_destroy(b->filter);
+       if (tcf_bpf_is_ebpf(prog))
+               bpf_prog_put(prog->filter);
+       else
+               bpf_prog_destroy(prog->filter);
 }
 
-static struct tc_action_ops act_bpf_ops = {
-       .kind =         "bpf",
-       .type =         TCA_ACT_BPF,
-       .owner        THIS_MODULE,
-       .act =          tcf_bpf,
-       .dump =         tcf_bpf_dump,
-       .cleanup =      tcf_bpf_cleanup,
-       .init =         tcf_bpf_init,
+static struct tc_action_ops act_bpf_ops __read_mostly = {
+       .kind           =       "bpf",
+       .type           =       TCA_ACT_BPF,
+       .owner          =       THIS_MODULE,
+       .act            =       tcf_bpf,
+       .dump           =       tcf_bpf_dump,
+       .cleanup        =       tcf_bpf_cleanup,
+       .init           =       tcf_bpf_init,
 };
 
 static int __init bpf_init_module(void)