u32 off = skb_mac_header_len(skb);
int ret;
- if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
- return -ENOTSUPP;
-
ret = skb_cow(skb, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
struct skb_shared_info *shinfo = skb_shinfo(skb);
- /* SKB_GSO_TCPV4 needs to be changed into
- * SKB_GSO_TCPV6.
- */
+ /* SKB_GSO_TCPV4 needs to be changed into SKB_GSO_TCPV6. */
if (shinfo->gso_type & SKB_GSO_TCPV4) {
shinfo->gso_type &= ~SKB_GSO_TCPV4;
shinfo->gso_type |= SKB_GSO_TCPV6;
}
-
- /* Due to IPv6 header, MSS needs to be downgraded. */
- skb_decrease_gso_size(shinfo, len_diff);
- /* Header must be checked, and gso_segs recomputed. */
- shinfo->gso_type |= SKB_GSO_DODGY;
- shinfo->gso_segs = 0;
}
skb->protocol = htons(ETH_P_IPV6);
u32 off = skb_mac_header_len(skb);
int ret;
- if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
- return -ENOTSUPP;
-
ret = skb_unclone(skb, GFP_ATOMIC);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
struct skb_shared_info *shinfo = skb_shinfo(skb);
- /* SKB_GSO_TCPV6 needs to be changed into
- * SKB_GSO_TCPV4.
- */
+ /* SKB_GSO_TCPV6 needs to be changed into SKB_GSO_TCPV4. */
if (shinfo->gso_type & SKB_GSO_TCPV6) {
shinfo->gso_type &= ~SKB_GSO_TCPV6;
shinfo->gso_type |= SKB_GSO_TCPV4;
}
-
- /* Due to IPv4 header, MSS can be upgraded. */
- skb_increase_gso_size(shinfo, len_diff);
- /* Header must be checked, and gso_segs recomputed. */
- shinfo->gso_type |= SKB_GSO_DODGY;
- shinfo->gso_segs = 0;
}
skb->protocol = htons(ETH_P_IP);
.arg2_type = ARG_ANYTHING,
};
+/* XDP_REDIRECT works by a three-step process, implemented in the functions
+ * below:
+ *
+ * 1. The bpf_redirect() and bpf_redirect_map() helpers will lookup the target
+ * of the redirect and store it (along with some other metadata) in a per-CPU
+ * struct bpf_redirect_info.
+ *
+ * 2. When the program returns the XDP_REDIRECT return code, the driver will
+ * call xdp_do_redirect() which will use the information in struct
+ * bpf_redirect_info to actually enqueue the frame into a map type-specific
+ * bulk queue structure.
+ *
+ * 3. Before exiting its NAPI poll loop, the driver will call xdp_do_flush(),
+ * which will flush all the different bulk queues, thus completing the
+ * redirect.
+ *
+ * Pointers to the map entries will be kept around for this whole sequence of
+ * steps, protected by RCU. However, there is no top-level rcu_read_lock() in
+ * the core code; instead, the RCU protection relies on everything happening
+ * inside a single NAPI poll sequence, which means it's between a pair of calls
+ * to local_bh_disable()/local_bh_enable().
+ *
+ * The map entries are marked as __rcu and the map code makes sure to
+ * dereference those pointers with rcu_dereference_check() in a way that works
+ * for both sections that to hold an rcu_read_lock() and sections that are
+ * called from NAPI without a separate rcu_read_lock(). The code below does not
+ * use RCU annotations, but relies on those in the map code.
+ */
void xdp_do_flush(void)
{
__dev_flush();
}
EXPORT_SYMBOL_GPL(xdp_do_flush);
+void bpf_clear_redirect_map(struct bpf_map *map)
+{
+ struct bpf_redirect_info *ri;
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ ri = per_cpu_ptr(&bpf_redirect_info, cpu);
+ /* Avoid polluting remote cacheline due to writes if
+ * not needed. Once we pass this test, we need the
+ * cmpxchg() to make sure it hasn't been changed in
+ * the meantime by remote CPU.
+ */
+ if (unlikely(READ_ONCE(ri->map) == map))
+ cmpxchg(&ri->map, map, NULL);
+ }
+}
+
int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
struct bpf_prog *xdp_prog)
{
enum bpf_map_type map_type = ri->map_type;
void *fwd = ri->tgt_value;
u32 map_id = ri->map_id;
+ struct bpf_map *map;
int err;
ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
case BPF_MAP_TYPE_DEVMAP:
fallthrough;
case BPF_MAP_TYPE_DEVMAP_HASH:
- err = dev_map_enqueue(fwd, xdp, dev);
+ map = READ_ONCE(ri->map);
+ if (unlikely(map)) {
+ WRITE_ONCE(ri->map, NULL);
+ err = dev_map_enqueue_multi(xdp, dev, map,
+ ri->flags & BPF_F_EXCLUDE_INGRESS);
+ } else {
+ err = dev_map_enqueue(fwd, xdp, dev);
+ }
break;
case BPF_MAP_TYPE_CPUMAP:
err = cpu_map_enqueue(fwd, xdp, dev);
enum bpf_map_type map_type, u32 map_id)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
+ struct bpf_map *map;
int err;
switch (map_type) {
case BPF_MAP_TYPE_DEVMAP:
fallthrough;
case BPF_MAP_TYPE_DEVMAP_HASH:
- err = dev_map_generic_redirect(fwd, skb, xdp_prog);
+ map = READ_ONCE(ri->map);
+ if (unlikely(map)) {
+ WRITE_ONCE(ri->map, NULL);
+ err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
+ ri->flags & BPF_F_EXCLUDE_INGRESS);
+ } else {
+ err = dev_map_generic_redirect(fwd, skb, xdp_prog);
+ }
if (unlikely(err))
goto err;
break;
static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
struct sock_reuseport *reuse,
struct sock *sk, struct sk_buff *skb,
+ struct sock *migrating_sk,
u32 hash)
{
reuse_kern->skb = skb;
reuse_kern->sk = sk;
reuse_kern->selected_sk = NULL;
+ reuse_kern->migrating_sk = migrating_sk;
reuse_kern->data_end = skb->data + skb_headlen(skb);
reuse_kern->hash = hash;
reuse_kern->reuseport_id = reuse->reuseport_id;
struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
struct bpf_prog *prog, struct sk_buff *skb,
+ struct sock *migrating_sk,
u32 hash)
{
struct sk_reuseport_kern reuse_kern;
enum sk_action action;
- bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, hash);
+ bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, migrating_sk, hash);
action = BPF_PROG_RUN(prog, &reuse_kern);
if (action == SK_PASS)
return &sk_reuseport_load_bytes_proto;
case BPF_FUNC_skb_load_bytes_relative:
return &sk_reuseport_load_bytes_relative_proto;
+ case BPF_FUNC_get_socket_cookie:
+ return &bpf_get_socket_ptr_cookie_proto;
default:
return bpf_base_func_proto(func_id);
}
case offsetof(struct sk_reuseport_md, hash):
return size == size_default;
+ case offsetof(struct sk_reuseport_md, sk):
+ info->reg_type = PTR_TO_SOCKET;
+ return size == sizeof(__u64);
+
+ case offsetof(struct sk_reuseport_md, migrating_sk):
+ info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
+ return size == sizeof(__u64);
+
/* Fields that allow narrowing */
case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
if (size < sizeof_field(struct sk_buff, protocol))
case offsetof(struct sk_reuseport_md, bind_inany):
SK_REUSEPORT_LOAD_FIELD(bind_inany);
break;
+
+ case offsetof(struct sk_reuseport_md, sk):
+ SK_REUSEPORT_LOAD_FIELD(sk);
+ break;
+
+ case offsetof(struct sk_reuseport_md, migrating_sk):
+ SK_REUSEPORT_LOAD_FIELD(migrating_sk);
+ break;
}
return insn - insn_buf;
projects / linux-2.6-microblaze.git / blobdiff