bpftool: Add bpftool-token manpage

Add bpftool-token manpage with information and examples of token-related
commands.

Suggested-by: Quentin Monnet <[email protected]>
Reviewed-by: Quentin Monnet <[email protected]>
Signed-off-by: Tao Chen <[email protected]>

Author: Tao Chen

tools/bpf/bpftool/Documentation/bpftool-token.rst

@@ -0,0 +1,64 @@
+.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+================
+bpftool-token
+================
+-------------------------------------------------------------------------------
+tool for inspection and simple manipulation of eBPF tokens
+-------------------------------------------------------------------------------
+
+:Manual section: 8
+
+.. include:: substitutions.rst
+
+SYNOPSIS
+========
+
+**bpftool** [*OPTIONS*] **token** *COMMAND*
+
+*OPTIONS* := { |COMMON_OPTIONS| }
+
+*COMMANDS* := { **show** | **list** | **help** }
+
+TOKEN COMMANDS
+===============
+
+| **bpftool** **token** { **show** | **list** }
+| **bpftool** **token help**
+|
+
+DESCRIPTION
+===========
+bpftool token { show | list }
+    List BPF token information for each *bpffs* mount point containing token
+    information on the system. Information include mount point path, allowed
+    **bpf**\ () system call commands, maps, programs, and attach types for the
+    token.
+
+bpftool prog help
+    Print short help message.
+
+OPTIONS
+========
+.. include:: common_options.rst
+
+EXAMPLES
+========
+|
+| **# mkdir -p /sys/fs/bpf/token**
+| **# mount -t bpf bpffs /sys/fs/bpf/token** \
+|         **-o delegate_cmds=prog_load:map_create** \
+|         **-o delegate_progs=kprobe** \
+|         **-o delegate_attachs=xdp**
+| **# bpftool token list**
+
+::
+
+    token_info  /sys/fs/bpf/token
+            allowed_cmds:
+              map_create          prog_load
+            allowed_maps:
+            allowed_progs:
+              kprobe
+            allowed_attachs:
+              xdp