Documentation: Added table for program type and its helper functions (#1881)

* Documentation: Added table for program type and its helper functions

* updated the Program type table to follow the same Markdown format as other tables

* Fixed typos

* fixed typos and added new helper functions

docs/kernel-versions.md

@@ -232,3 +232,36 @@ Note: GPL-only BPF helpers require a GPL-compatible license. The current license
 * Dual MPL/GPL
 
 Check the list of GPL-compatible licenses in your [kernel source code](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/linux/license.h).
+
+## Program Types
+The list of program types and supported helper functions can be retrieved with:
+
+    git grep -W 'func_proto(enum bpf_func_id func_id' kernel/ net/ drivers/
+
+|Program Type| Helper Functions|
+|------------|-----------------|
+|`BPF_PROG_TYPE_SOCKET_FILTER`|`BPF_FUNC_get_current_uid_gid()` <br> `Base functions`|
+|`BPF_PROG_TYPE_KPROBE`|`BPF_FUNC_perf_event_output()` <br> `BPF_FUNC_get_stackid()` <br> `BPF_FUNC_get_stack()` <br> `BPF_FUNC_perf_event_read_value()` <br> `BPF_FUNC_override_return()` <br> `Tracing functions`|
+|`BPF_PROG_TYPE_SCHED_CLS` <br> `BPF_PROG_TYPE_SCHED_ACT`|`BPF_FUNC_skb_store_bytes()` <br> `BPF_FUNC_skb_load_bytes()` <br> `BPF_FUNC_skb_load_bytes_relative()` <br> `BPF_FUNC_skb_pull_data()` <br> `BPF_FUNC_csum_diff()` <br> `BPF_FUNC_csum_update()` <br> `BPF_FUNC_l3_csum_replace()` <br> `BPF_FUNC_l4_csum_replace()` <br> `BPF_FUNC_clone_redirect()` <br> `BPF_FUNC_get_cgroup_classid()` <br> `BPF_FUNC_skb_vlan_push()` <br> `BPF_FUNC_skb_vlan_pop()` <br> `BPF_FUNC_skb_change_proto()` <br> `BPF_FUNC_skb_change_type()` <br> `BPF_FUNC_skb_adjust_room()` <br> `BPF_FUNC_skb_change_tail()` <br> `BPF_FUNC_skb_get_tunnel_key()` <br> `BPF_FUNC_skb_set_tunnel_key()` <br> `BPF_FUNC_skb_get_tunnel_opt()` <br> `BPF_FUNC_skb_set_tunnel_opt()` <br> `BPF_FUNC_redirect()` <br> `BPF_FUNC_get_route_realm()` <br> `BPF_FUNC_get_hash_recalc()` <br> `BPF_FUNC_set_hash_invalid()` <br> `BPF_FUNC_set_hash()` <br> `BPF_FUNC_perf_event_output()` <br> `BPF_FUNC_get_smp_processor_id()` <br> `BPF_FUNC_skb_under_cgroup()` <br> `BPF_FUNC_get_socket_cookie()` <br> `BPF_FUNC_get_socket_uid()` <br> `BPF_FUNC_fib_lookup()` <br> `BPF_FUNC_skb_get_xfrm_state()` <br> `BPF_FUNC_skb_cgroup_id()` <br> `Base functions`|
+|`BPF_PROG_TYPE_TRACEPOINT`|`BPF_FUNC_perf_event_output()` <br> `BPF_FUNC_get_stackid()` <br> `BPF_FUNC_get_stack()` <br> `Tracing functions`|
+|`BPF_PROG_TYPE_XDP`| `BPF_FUNC_perf_event_output()` <br> `BPF_FUNC_get_smp_processor_id()` <br> `BPF_FUNC_csum_diff()` <br> `BPF_FUNC_xdp_adjust_head()` <br> `BPF_FUNC_xdp_adjust_meta()` <br> `BPF_FUNC_redirect()` <br> `BPF_FUNC_redirect_map()` <br> `BPF_FUNC_xdp_adjust_tail()` <br> `BPF_FUNC_fib_lookup()` <br> `Base functions`|
+|`BPF_PROG_TYPE_PERF_EVENT`| `BPF_FUNC_perf_event_output()` <br> `BPF_FUNC_get_stackid()` <br> `BPF_FUNC_get_stack()` <br> `BPF_FUNC_perf_prog_read_value()` <br> `Tracing functions`|
+|`BPF_PROG_TYPE_CGROUP_SKB`|`BPF_FUNC_skb_load_bytes()` <br> `BPF_FUNC_skb_load_bytes_relative()` <br> `BPF_FUNC_get_socket_cookie()` <br> `BPF_FUNC_get_socket_uid()` <br> `Base functions`|
+|`BPF_PROG_TYPE_CGROUP_SOCK`|`BPF_FUNC_get_current_uid_gid()` <br> `Base functions`|
+|`BPF_PROG_TYPE_LWT_IN`|`BPF_FUNC_lwt_push_encap()` <br> `LWT functions` <br> `Base functions`|
+|`BPF_PROG_TYPE_LWT_OUT`| `LWT functions` <br> `Base functions`|
+|`BPF_PROG_TYPE_LWT_XMIT`| `BPF_FUNC_skb_get_tunnel_key()` <br> `BPF_FUNC_skb_set_tunnel_key()` <br> `BPF_FUNC_skb_get_tunnel_opt()` <br> `BPF_FUNC_skb_set_tunnel_opt()` <br> `BPF_FUNC_redirect()` <br> `BPF_FUNC_clone_redirect()` <br> `BPF_FUNC_skb_change_tail()` <br> `BPF_FUNC_skb_change_head()` <br> `BPF_FUNC_skb_store_bytes()` <br> `BPF_FUNC_csum_update()` <br> `BPF_FUNC_l3_csum_replace()` <br> `BPF_FUNC_l4_csum_replace()` <br> `BPF_FUNC_set_hash_invalid()` <br> `LWT functions`|
+|`BPF_PROG_TYPE_SOCK_OPS`|`BPF_FUNC_setsockopt()` <br> `BPF_FUNC_getsockopt()` <br> `BPF_FUNC_sock_ops_cb_flags_set()` <br> `BPF_FUNC_sock_map_update()` <br> `BPF_FUNC_sock_hash_update()` <br> `BPF_FUNC_get_socket_cookie()` <br> `Base functions`|
+|`BPF_PROG_TYPE_SK_SKB`|`BPF_FUNC_skb_store_bytes()` <br> `BPF_FUNC_skb_load_bytes()` <br> `BPF_FUNC_skb_pull_data()` <br> `BPF_FUNC_skb_change_tail()` <br> `BPF_FUNC_skb_change_head()` <br> `BPF_FUNC_get_socket_cookie()` <br> `BPF_FUNC_get_socket_uid()` <br> `BPF_FUNC_sk_redirect_map()` <br> `BPF_FUNC_sk_redirect_hash()` <br> `Base functions`|
+|`BPF_PROG_TYPE_CGROUP_DEVICE`|`BPF_FUNC_map_lookup_elem()` <br> `BPF_FUNC_map_update_elem()` <br> `BPF_FUNC_map_delete_elem()` <br> `BPF_FUNC_get_current_uid_gid()` <br> `BPF_FUNC_trace_printk()`|
+|`BPF_PROG_TYPE_SK_MSG`|`BPF_FUNC_msg_redirect_map()` <br> `BPF_FUNC_msg_redirect_hash()` <br> `BPF_FUNC_msg_apply_bytes()` <br> `BPF_FUNC_msg_cork_bytes()` <br> `BPF_FUNC_msg_pull_data()` <br> `Base functions`|
+|`BPF_PROG_TYPE_RAW_TRACEPOINT`|`BPF_FUNC_perf_event_output()` <br> `BPF_FUNC_get_stackid()` <br> `BPF_FUNC_get_stack()` <br> `Tracing functions`|
+|`BPF_PROG_TYPE_CGROUP_SOCK_ADDR`|`BPF_FUNC_get_current_uid_gid()` <br> `BPF_FUNC_bind()` <br> `BPF_FUNC_get_socket_cookie()` <br> `Base functions`|
+|`BPF_PROG_TYPE_LWT_SEG6LOCAL`|`BPF_FUNC_lwt_seg6_store_bytes()` <br> `BPF_FUNC_lwt_seg6_action()` <br> `BPF_FUNC_lwt_seg6_adjust_srh()` <br> `LWT functions`|
+|`BPF_PROG_TYPE_LIRC_MODE2`|`BPF_FUNC_rc_repeat()` <br> `BPF_FUNC_rc_keydown()` <br> `BPF_FUNC_map_lookup_elem()` <br> `BPF_FUNC_map_update_elem()` <br> `BPF_FUNC_map_delete_elem()` <br> `BPF_FUNC_ktime_get_ns()` <br> `BPF_FUNC_tail_call()` <br> `BPF_FUNC_get_prandom_u32()` <br> `BPF_FUNC_trace_printk()`|
+
+|Function Group| Functions|
+|------------------|-------|
+|`Base functions`| `BPF_FUNC_map_lookup_elem()` <br> `BPF_FUNC_map_update_elem()` <br> `BPF_FUNC_map_delete_elem()` <br> `BPF_FUNC_get_prandom_u32()` <br> `BPF_FUNC_get_smp_processor_id()` <br> `BPF_FUNC_get_numa_node_id()` <br> `BPF_FUNC_tail_call()` <br> `BPF_FUNC_ktime_get_ns()` <br> `BPF_FUNC_trace_printk()`|
+|`Tracing functions`|`BPF_FUNC_map_lookup_elem()` <br> `BPF_FUNC_map_update_elem()` <br> `BPF_FUNC_map_delete_elem()` <br> `BPF_FUNC_probe_read()` <br> `BPF_FUNC_ktime_get_ns()` <br> `BPF_FUNC_tail_call()` <br> `BPF_FUNC_get_current_pid_tgid()` <br> `BPF_FUNC_get_current_task()` <br> `BPF_FUNC_get_current_uid_gid()` <br> `BPF_FUNC_get_current_comm()` <br> `BPF_FUNC_trace_printk()` <br> `BPF_FUNC_get_smp_processor_id()` <br> `BPF_FUNC_get_numa_node_id()` <br> `BPF_FUNC_perf_event_read()` <br> `BPF_FUNC_probe_write_user()` <br> `BPF_FUNC_current_task_under_cgroup()` <br> `BPF_FUNC_get_prandom_u32()` <br> `BPF_FUNC_probe_read_str()` <br> `BPF_FUNC_get_current_cgroup_id()` |
+|`LWT functions`|  `BPF_FUNC_skb_load_bytes()` <br> `BPF_FUNC_skb_pull_data()` <br> `BPF_FUNC_csum_diff()` <br> `BPF_FUNC_get_cgroup_classid()` <br> `BPF_FUNC_get_route_realm()` <br> `BPF_FUNC_get_hash_recalc()` <br> `BPF_FUNC_perf_event_output()` <br> `BPF_FUNC_get_smp_processor_id()` <br> `BPF_FUNC_skb_under_cgroup()`|