Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 108 insertions, 0 deletions

diff --git a/tools/bpf/bpftool/Documentation/bpftool-link.rst b/tools/bpf/bpftool/Documentation/bpftool-link.rst
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+================
+bpftool-link
+================
+-------------------------------------------------------------------------------
+tool for inspection and simple manipulation of eBPF links
+-------------------------------------------------------------------------------
+
+:Manual section: 8
+
+SYNOPSIS
+========
+
+	**bpftool** [*OPTIONS*] **link** *COMMAND*
+
+	*OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } }
+
+	*COMMANDS* := { **show** | **list** | **pin** | **help** }
+
+LINK COMMANDS
+=============
+
+|	**bpftool** **link { show | list }** [*LINK*]
+|	**bpftool** **link pin** *LINK* *FILE*
+|	**bpftool** **link detach** *LINK*
+|	**bpftool** **link help**
+|
+|	*LINK* := { **id** *LINK_ID* | **pinned** *FILE* }
+
+
+DESCRIPTION
+===========
+	**bpftool link { show | list }** [*LINK*]
+		  Show information about active links. If *LINK* is
+		  specified show information only about given link,
+		  otherwise list all links currently active on the system.
+
+		  Output will start with link ID followed by link type and
+		  zero or more named attributes, some of which depend on type
+		  of link.
+
+		  Since Linux 5.8 bpftool is able to discover information about
+		  processes that hold open file descriptors (FDs) against BPF
+		  links. On such kernels bpftool will automatically emit this
+		  information as well.
+
+	**bpftool link pin** *LINK* *FILE*
+		  Pin link *LINK* as *FILE*.
+
+		  Note: *FILE* must be located in *bpffs* mount. It must not
+		  contain a dot character ('.'), which is reserved for future
+		  extensions of *bpffs*.
+
+	**bpftool link detach** *LINK*
+		  Force-detach link *LINK*. BPF link and its underlying BPF
+		  program will stay valid, but they will be detached from the
+		  respective BPF hook and BPF link will transition into
+		  a defunct state until last open file descriptor for that
+		  link is closed.
+
+	**bpftool link help**
+		  Print short help message.
+
+OPTIONS
+=======
+	.. include:: common_options.rst
+
+	-f, --bpffs
+		  When showing BPF links, show file names of pinned
+		  links.
+
+	-n, --nomount
+		  Do not automatically attempt to mount any virtual file system
+		  (such as tracefs or BPF virtual file system) when necessary.
+
+EXAMPLES
+========
+**# bpftool link show**
+
+::
+
+    10: cgroup  prog 25
+            cgroup_id 614  attach_type egress
+            pids test_progs(223)
+
+**# bpftool --json --pretty link show**
+
+::
+
+    [{
+            "type": "cgroup",
+            "prog_id": 25,
+            "cgroup_id": 614,
+            "attach_type": "egress",
+            "pids": [{
+                    "pid": 223,
+                    "comm": "test_progs"
+                }
+            ]
+        }
+    ]
+
+|
+| **# bpftool link pin id 10 /sys/fs/bpf/link**
+| **# ls -l /sys/fs/bpf/**
+
+::
+
+    -rw------- 1 root root 0 Apr 23 21:39 link