tools/bpftool: Add documentation and bash-completion for `link detach`

Add info on link detach sub-command to man page. Add detach to bash-completion
as well.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com.
Link: https://lore.kernel.org/bpf/20200731182830.286260-6-andriin@fb.com

diff --git a/tools/bpf/bpftool/Documentation/bpftool-link.rst b/tools/bpf/bpftool/Documentation/bpftool-link.rst
index 38b0949a185b991bcd7bbaaec9f8b605317c35eb..4a52e7a933399c0df5e6e50ef32e02af25c70799 100644 (file)
--- a/tools/bpf/bpftool/Documentation/bpftool-link.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-link.rst
@@ -21,6 +21,7 @@ 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* }
@@ -49,6 +50,13 @@ DESCRIPTION
                  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.
 

diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool
index 257fa310ea2bb2444639df903bc61b7ab5b3e0f5..f53ed2f1a4aafd9a6d9d2ab72a4c0998bf26b074 100644 (file)
--- a/tools/bpf/bpftool/bash-completion/bpftool
+++ b/tools/bpf/bpftool/bash-completion/bpftool
@@ -1122,7 +1122,7 @@ _bpftool()
             ;;
         link)
             case $command in
-                show|list|pin)
+                show|list|pin|detach)
                     case $prev in
                         id)
                             _bpftool_get_link_ids
@@ -1139,7 +1139,7 @@ _bpftool()
                     COMPREPLY=( $( compgen -W "$LINK_TYPE" -- "$cur" ) )
                     return 0
                     ;;
-                pin)
+                pin|detach)
                     if [[ $prev == "$command" ]]; then
                         COMPREPLY=( $( compgen -W "$LINK_TYPE" -- "$cur" ) )
                     else