sync with latest libbpf repo

sync with libbpf v0.2.0

Signed-off-by: Yonghong Song <[email protected]>

docs/kernel-versions.md

@@ -199,6 +199,8 @@ Alphabetical order
 Helper | Kernel version | License | Commit |
 -------|----------------|---------|--------|
 `BPF_FUNC_bind()` | 4.17 | | [`d74bad4e74ee`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d74bad4e74ee373787a9ae24197c17b7cdc428d5) |
+`BPF_FUNC_bpf_per_cpu_ptr()` | 5.10 | | [`eaa6bcb71ef6`](https://github.com/torvalds/linux/commit/eaa6bcb71ef6ed3dc18fc525ee7e293b06b4882b) |
+`BPF_FUNC_bpf_this_cpu_ptr()` | 5.10 | | [`63d9b80dcf2c`](https://github.com/torvalds/linux/commit/63d9b80dcf2c67bc5ade61cbbaa09d7af21f43f1) |
 `BPF_FUNC_clone_redirect()` | 4.2 | | [`3896d655f4d4`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3896d655f4d491c67d669a15f275a39f713410f8)
 `BPF_FUNC_copy_from_user()` | 5.10 | | [`07be4c4a3e7a`](https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit?id=07be4c4a3e7a0db148e44b16c5190e753d1c8569)
 `BPF_FUNC_csum_diff()` | 4.6 | | [`7d672345ed29`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7d672345ed295b1356a5d9f7111da1d1d7d65867)
@@ -272,6 +274,7 @@ Helper | Kernel version | License | Commit |
 `BPF_FUNC_redirect()` | 4.4 | | [`27b29f63058d`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=27b29f63058d26c6c1742f1993338280d5a41dc6)
 `BPF_FUNC_redirect_map()` | 4.14 | | [`97f91a7cf04f`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=97f91a7cf04ff605845c20948b8a80e54cbd3376)
 `BPF_FUNC_redirect_neigh()` | 5.10 | | [`b4ab31414970`](https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=b4ab31414970a7a03a5d55d75083f2c101a30592)
+`BPF_FUNC_redirect_peer()` | 5.10 | | [`9aa1206e8f48`](https://github.com/torvalds/linux/commit/9aa1206e8f48222f35a0c809f33b2f4aaa1e2661)
 `BPF_FUNC_reserve_hdr_opt()` | 5.10 | | [`0813a841566f`](https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit?id=0813a841566f0962a5551be7749b43c45f0022a0)
 `BPF_FUNC_ringbuf_discard()` | 5.8 | | [`457f44363a88`](https://github.com/torvalds/linux/commit/457f44363a8894135c85b7a9afd2bd8196db24ab)
 `BPF_FUNC_ringbuf_output()` | 5.8 | | [`457f44363a88`](https://github.com/torvalds/linux/commit/457f44363a8894135c85b7a9afd2bd8196db24ab)

src/cc/compat/linux/virtual_bpf.h

@@ -357,18 +357,36 @@ enum bpf_link_type {
 #define BPF_F_SLEEPABLE (1U << 4)
 
 /* When BPF ldimm64's insn[0].src_reg != 0 then this can have
- * two extensions:
- *
- * insn[0].src_reg: BPF_PSEUDO_MAP_FD BPF_PSEUDO_MAP_VALUE
- * insn[0].imm: map fd map fd
- * insn[1].imm: 0 offset into value
- * insn[0].off: 0 0
- * insn[1].off: 0 0
- * ldimm64 rewrite: address of map address of map[0]+offset
- * verifier type: CONST_PTR_TO_MAP PTR_TO_MAP_VALUE
+ * the following extensions:
+ *
+ * insn[0].src_reg: BPF_PSEUDO_MAP_FD
+ * insn[0].imm: map fd
+ * insn[1].imm: 0
+ * insn[0].off: 0
+ * insn[1].off: 0
+ * ldimm64 rewrite: address of map
+ * verifier type: CONST_PTR_TO_MAP
  */
 #define BPF_PSEUDO_MAP_FD 1
+/* insn[0].src_reg: BPF_PSEUDO_MAP_VALUE
+ * insn[0].imm: map fd
+ * insn[1].imm: offset into value
+ * insn[0].off: 0
+ * insn[1].off: 0
+ * ldimm64 rewrite: address of map[0]+offset
+ * verifier type: PTR_TO_MAP_VALUE
+ */
 #define BPF_PSEUDO_MAP_VALUE 2
+/* insn[0].src_reg: BPF_PSEUDO_BTF_ID
+ * insn[0].imm: kernel btd id of VAR
+ * insn[1].imm: 0
+ * insn[0].off: 0
+ * insn[1].off: 0
+ * ldimm64 rewrite: address of the kernel variable
+ * verifier type: PTR_TO_BTF_ID or PTR_TO_MEM, depending on whether the var
+ * is struct/union.
+ */
+#define BPF_PSEUDO_BTF_ID 3
 
 /* when bpf_call->src_reg == BPF_PSEUDO_CALL, bpf_call->imm == pc-relative
  * offset to another bpf function
@@ -415,6 +433,12 @@ enum {
 
 /* Enable memory-mapping BPF map */
  BPF_F_MMAPABLE = (1U << 10),
+
+/* Share perf_event among processes */
+ BPF_F_PRESERVE_ELEMS = (1U << 11),
+
+/* Create a map that is suitable to be an inner map with dynamic max entries */
+ BPF_F_INNER_MAP = (1U << 12),
 };
 
 /* Flags for BPF_PROG_QUERY. */
@@ -1678,7 +1702,7 @@ union bpf_attr {
  * **TCP_CONGESTION**, **TCP_BPF_IW**,
  * **TCP_BPF_SNDCWND_CLAMP**, **TCP_SAVE_SYN**,
  * **TCP_KEEPIDLE**, **TCP_KEEPINTVL**, **TCP_KEEPCNT**,
- *  **TCP_SYNCNT**, **TCP_USER_TIMEOUT**.
+ * **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**.
  * * **IPPROTO_IP**, which supports *optname* **IP_TOS**.
  * * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
  * Return
@@ -2233,7 +2257,7 @@ union bpf_attr {
  * Description
  * This helper is used in programs implementing policies at the
  * skb socket level. If the sk_buff *skb* is allowed to pass (i.e.
- * if the verdeict eBPF program returns **SK_PASS**), redirect it
+ * if the verdict eBPF program returns **SK_PASS**), redirect it
  * to the socket referenced by *map* (of type
  * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and
  * egress interfaces can be used for redirection. The
@@ -3654,15 +3678,68 @@ union bpf_attr {
  * Return
  * The id is returned or 0 in case the id could not be retrieved.
  *
- * long bpf_redirect_neigh(u32 ifindex, u64 flags)
+ * long bpf_redirect_neigh(u32 ifindex, struct bpf_redir_neigh *params, int plen, u64 flags)
  * Description
  * Redirect the packet to another net device of index *ifindex*
  * and fill in L2 addresses from neighboring subsystem. This helper
  * is somewhat similar to **bpf_redirect**\ (), except that it
- * fills in e.g. MAC addresses based on the L3 information from
- * the packet. This helper is supported for IPv4 and IPv6 protocols.
+ * populates L2 addresses as well, meaning, internally, the helper
+ * relies on the neighbor lookup for the L2 address of the nexthop.
+ *
+ * The helper will perform a FIB lookup based on the skb's
+ * networking header to get the address of the next hop, unless
+ * this is supplied by the caller in the *params* argument. The
+ * *plen* argument indicates the len of *params* and should be set
+ * to 0 if *params* is NULL.
+ *
+ * The *flags* argument is reserved and must be 0. The helper is
+ * currently only supported for tc BPF program types, and enabled
+ * for IPv4 and IPv6 protocols.
+ * Return
+ * The helper returns **TC_ACT_REDIRECT** on success or
+ * **TC_ACT_SHOT** on error.
+ *
+ * void *bpf_per_cpu_ptr(const void *percpu_ptr, u32 cpu)
+ * Description
+ * Take a pointer to a percpu ksym, *percpu_ptr*, and return a
+ * pointer to the percpu kernel variable on *cpu*. A ksym is an
+ * extern variable decorated with '__ksym'. For ksym, there is a
+ * global var (either static or global) defined of the same name
+ * in the kernel. The ksym is percpu if the global var is percpu.
+ * The returned pointer points to the global percpu var on *cpu*.
+ *
+ * bpf_per_cpu_ptr() has the same semantic as per_cpu_ptr() in the
+ * kernel, except that bpf_per_cpu_ptr() may return NULL. This
+ * happens if *cpu* is larger than nr_cpu_ids. The caller of
+ * bpf_per_cpu_ptr() must check the returned value.
+ * Return
+ * A pointer pointing to the kernel percpu variable on *cpu*, or
+ * NULL, if *cpu* is invalid.
+ *
+ * void *bpf_this_cpu_ptr(const void *percpu_ptr)
+ * Description
+ * Take a pointer to a percpu ksym, *percpu_ptr*, and return a
+ * pointer to the percpu kernel variable on this cpu. See the
+ * description of 'ksym' in **bpf_per_cpu_ptr**\ ().
+ *
+ * bpf_this_cpu_ptr() has the same semantic as this_cpu_ptr() in
+ * the kernel. Different from **bpf_per_cpu_ptr**\ (), it would
+ * never return NULL.
+ * Return
+ * A pointer pointing to the kernel percpu variable on this cpu.
+ *
+ * long bpf_redirect_peer(u32 ifindex, u64 flags)
+ * Description
+ * Redirect the packet to another net device of index *ifindex*.
+ * This helper is somewhat similar to **bpf_redirect**\ (), except
+ * that the redirection happens to the *ifindex*' peer device and
+ * the netns switch takes place from ingress to ingress without
+ * going through the CPU's backlog queue.
+ *
  * The *flags* argument is reserved and must be 0. The helper is
- * currently only supported for tc BPF program types.
+ * currently only supported for tc BPF program types at the ingress
+ * hook and for veth device types. The peer device must reside in a
+ * different network namespace.
  * Return
  * The helper returns **TC_ACT_REDIRECT** on success or
  * **TC_ACT_SHOT** on error.
@@ -3821,6 +3898,9 @@ union bpf_attr {
  FN(seq_printf_btf), \
  FN(skb_cgroup_classid), \
  FN(redirect_neigh), \
+ FN(bpf_per_cpu_ptr), \
+ FN(bpf_this_cpu_ptr), \
+ FN(redirect_peer), \
  /* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
@@ -4831,6 +4911,16 @@ struct bpf_fib_lookup {
  __u8 dmac[6]; /* ETH_ALEN */
 };
 
+struct bpf_redir_neigh {
+ /* network family for lookup (AF_INET, AF_INET6) */
+ __u32 nh_family;
+ /* network address of nexthop; skips fib lookup to find gateway */
+ union {
+ __be32 ipv4_nh;
+ __u32 ipv6_nh[4]; /* in6_addr; network order */
+ };
+};
+
 enum bpf_task_fd_type {
  BPF_FD_TYPE_RAW_TRACEPOINT, /* tp name */
  BPF_FD_TYPE_TRACEPOINT, /* tp name */

src/cc/export/helpers.h

@@ -784,16 +784,22 @@ static long (*bpf_d_path)(struct path *path, char *buf, u32 sz) =
 static long (*bpf_copy_from_user)(void *dst, u32 size, const void *user_ptr) =
  (void *)BPF_FUNC_copy_from_user;
 
-static long (*bpf_snprintf_btf)(char *str, __u32 str_size, struct btf_ptr *ptr,
- __u32 btf_ptr_size, __u64 flags) =
+static long (*bpf_snprintf_btf)(char *str, u32 str_size, struct btf_ptr *ptr,
+ u32 btf_ptr_size, u64 flags) =
  (void *)BPF_FUNC_snprintf_btf;
 static long (*bpf_seq_printf_btf)(struct seq_file *m, struct btf_ptr *ptr,
- __u32 ptr_size, __u64 flags) =
+ u32 ptr_size, u64 flags) =
  (void *)BPF_FUNC_seq_printf_btf;
-static __u64 (*bpf_skb_cgroup_classid)(struct __sk_buff *skb) =
+static u64 (*bpf_skb_cgroup_classid)(struct sk_buff *skb) =
  (void *)BPF_FUNC_skb_cgroup_classid;
-static long (*bpf_redirect_neigh)(__u32 ifindex, __u64 flags) =
+static long (*bpf_redirect_neigh)(u32 ifindex, struct bpf_redir_neigh *params,
+ u64 flags) =
  (void *)BPF_FUNC_redirect_neigh;
+static void * (*bpf_per_cpu_ptr)(const void *percpu_ptr, u32 cpu) =
+ (void *)BPF_FUNC_bpf_per_cpu_ptr;
+static void * (*bpf_this_cpu_ptr)(const void *percpu_ptr) =
+ (void *)BPF_FUNC_bpf_this_cpu_ptr;
+long (*bpf_redirect_peer)(u32 ifindex, u64 flags) = (void *)BPF_FUNC_redirect_peer;
 
 /* llvm builtin functions that eBPF C program may use to
  * emit BPF_LD_ABS and BPF_LD_IND instructions

src/cc/libbpf.c

@@ -251,6 +251,9 @@ static struct bpf_helper helpers[] = {
  {"seq_printf_btf", "5.10"},
  {"skb_cgroup_classid", "5.10"},
  {"redirect_neigh", "5.10"},
+ {"per_cpu_ptr", "5.10"},
+ {"this_cpu_ptr", "5.10"},
+ {"redirect_peer", "5.10"},
 };
 
 static uint64_t ptr_to_u64(void *ptr)