[linux.git] / tools / bpf / bpftool / Documentation / bpftool-map.rst

================
bpftool-map
================
-------------------------------------------------------------------------------
tool for inspection and simple manipulation of eBPF maps
-------------------------------------------------------------------------------

:Manual section: 8

SYNOPSIS
========

	**bpftool** [*OPTIONS*] **map** *COMMAND*

	*OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } }

	*COMMANDS* :=
	{ **show** | **list** | **create** | **dump** | **update** | **lookup** | **getnext**
	| **delete** | **pin** | **help** }

MAP COMMANDS
=============

|	**bpftool** **map { show | list }**   [*MAP*]
|	**bpftool** **map create**     *FILE* **type** *TYPE* **key** *KEY_SIZE* **value** *VALUE_SIZE* \
|		**entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**dev** *NAME*]
|	**bpftool** **map dump**       *MAP*
|	**bpftool** **map update**     *MAP*  **key** *DATA*   **value** *VALUE* [*UPDATE_FLAGS*]
|	**bpftool** **map lookup**     *MAP*  **key** *DATA*
|	**bpftool** **map getnext**    *MAP* [**key** *DATA*]
|	**bpftool** **map delete**     *MAP*  **key** *DATA*
|	**bpftool** **map pin**        *MAP*  *FILE*
|	**bpftool** **map event_pipe** *MAP* [**cpu** *N* **index** *M*]
|	**bpftool** **map help**
|
|	*MAP* := { **id** *MAP_ID* | **pinned** *FILE* }
|	*DATA* := { [**hex**] *BYTES* }
|	*PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
|	*VALUE* := { *DATA* | *MAP* | *PROG* }
|	*UPDATE_FLAGS* := { **any** | **exist** | **noexist** }
|	*TYPE* := { **hash** | **array** | **prog_array** | **perf_event_array** | **percpu_hash**
|		| **percpu_array** | **stack_trace** | **cgroup_array** | **lru_hash**
|		| **lru_percpu_hash** | **lpm_trie** | **array_of_maps** | **hash_of_maps**
|		| **devmap** | **sockmap** | **cpumap** | **xskmap** | **sockhash**
|		| **cgroup_storage** | **reuseport_sockarray** | **percpu_cgroup_storage** }

DESCRIPTION
===========
	**bpftool map { show | list }**   [*MAP*]
		  Show information about loaded maps.  If *MAP* is specified
		  show information only about given map, otherwise list all
		  maps currently loaded on the system.

		  Output will start with map ID followed by map type and
		  zero or more named attributes (depending on kernel version).

	**bpftool map create** *FILE* **type** *TYPE* **key** *KEY_SIZE* **value** *VALUE_SIZE*  **entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**dev** *NAME*]
		  Create a new map with given parameters and pin it to *bpffs*
		  as *FILE*.

	**bpftool map dump**    *MAP*
		  Dump all entries in a given *MAP*.

	**bpftool map update**  *MAP*  **key** *DATA*   **value** *VALUE* [*UPDATE_FLAGS*]
		  Update map entry for a given *KEY*.

		  *UPDATE_FLAGS* can be one of: **any** update existing entry
		  or add if doesn't exit; **exist** update only if entry already
		  exists; **noexist** update only if entry doesn't exist.

		  If the **hex** keyword is provided in front of the bytes
		  sequence, the bytes are parsed as hexadeximal values, even if
		  no "0x" prefix is added. If the keyword is not provided, then
		  the bytes are parsed as decimal values, unless a "0x" prefix
		  (for hexadecimal) or a "0" prefix (for octal) is provided.

	**bpftool map lookup**  *MAP*  **key** *DATA*
		  Lookup **key** in the map.

	**bpftool map getnext** *MAP* [**key** *DATA*]
		  Get next key.  If *key* is not specified, get first key.

	**bpftool map delete**  *MAP*  **key** *DATA*
		  Remove entry from the map.

	**bpftool map pin**     *MAP*  *FILE*
		  Pin map *MAP* 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** **map event_pipe** *MAP* [**cpu** *N* **index** *M*]
		  Read events from a BPF_MAP_TYPE_PERF_EVENT_ARRAY map.

		  Install perf rings into a perf event array map and dump
		  output of any bpf_perf_event_output() call in the kernel.
		  By default read the number of CPUs on the system and
		  install perf ring for each CPU in the corresponding index
		  in the array.

		  If **cpu** and **index** are specified, install perf ring
		  for given **cpu** at **index** in the array (single ring).

		  Note that installing a perf ring into an array will silently
		  replace any existing ring.  Any other application will stop
		  receiving events if it installed its rings earlier.

	**bpftool map help**
		  Print short help message.

OPTIONS
=======
	-h, --help
		  Print short generic help message (similar to **bpftool help**).

	-v, --version
		  Print version number (similar to **bpftool version**).

	-j, --json
		  Generate JSON output. For commands that cannot produce JSON, this
		  option has no effect.

	-p, --pretty
		  Generate human-readable JSON output. Implies **-j**.

	-f, --bpffs
		  Show file names of pinned maps.

EXAMPLES
========
**# bpftool map show**
::

  10: hash  name some_map  flags 0x0
	key 4B  value 8B  max_entries 2048  memlock 167936B

The following three commands are equivalent:

|
| **# bpftool map update id 10 key hex   20   c4   b7   00 value hex   0f   ff   ff   ab   01   02   03   4c**
| **# bpftool map update id 10 key     0x20 0xc4 0xb7 0x00 value     0x0f 0xff 0xff 0xab 0x01 0x02 0x03 0x4c**
| **# bpftool map update id 10 key       32  196  183    0 value       15  255  255  171    1    2    3   76**

**# bpftool map lookup id 10 key 0 1 2 3**

::

  key: 00 01 02 03 value: 00 01 02 03 04 05 06 07


**# bpftool map dump id 10**
::

  key: 00 01 02 03  value: 00 01 02 03 04 05 06 07
  key: 0d 00 07 00  value: 02 00 00 00 01 02 03 04
  Found 2 elements

**# bpftool map getnext id 10 key 0 1 2 3**
::

  key:
  00 01 02 03
  next key:
  0d 00 07 00

|
| **# mount -t bpf none /sys/fs/bpf/**
| **# bpftool map pin id 10 /sys/fs/bpf/map**
| **# bpftool map del pinned /sys/fs/bpf/map key 13 00 07 00**

SEE ALSO
========
	**bpf**\ (2),
	**bpf-helpers**\ (7),
	**bpftool**\ (8),
	**bpftool-prog**\ (8),
	**bpftool-cgroup**\ (8),
	**bpftool-net**\ (8),
	**bpftool-perf**\ (8)
Commit	Line	Data
ff69c21a JK	1	================
	2	bpftool-map
	3	================
	4	-------------------------------------------------------------------------------
	5	tool for inspection and simple manipulation of eBPF maps
	6	-------------------------------------------------------------------------------
	7
	8	:Manual section: 8
	9
	10	SYNOPSIS
	11	========
	12
0641c3c8 QM	13	bpftool [OPTIONS] map COMMAND
0641c3c8 QM	14
c541b734	15	OPTIONS := { { -j \| --json } [{ -p \| --pretty }] \| { -f \| --bpffs } }
ff69c21a JK	16
ff69c21a JK	17	COMMANDS :=
0b592b5a JK	18	{ show \| list \| create \| dump \| update \| lookup \| getnext
0b592b5a JK	19	\| delete \| pin \| help }
ff69c21a JK	20
	21	MAP COMMANDS
	22	=============
	23
6ebe6dbd	24	\| bpftool map { show \| list } [MAP]
0b592b5a JK	25	\| bpftool map create FILE type TYPE key KEY_SIZE value VALUE_SIZE \
0b592b5a JK	26	\| entries MAX_ENTRIES name NAME [flags FLAGS] [dev NAME]
f412eed9 JK	27	\| bpftool map dump MAP
	28	\| bpftool map update MAP key DATA value VALUE [UPDATE_FLAGS]
	29	\| bpftool map lookup MAP key DATA
	30	\| bpftool map getnext MAP [key DATA]
	31	\| bpftool map delete MAP key DATA
	32	\| bpftool map pin MAP FILE
	33	\| bpftool map event_pipe MAP [cpu N index M]
47ff7ac6	34	\| bpftool map help
ff69c21a	35	\|
47ff7ac6	36	\| MAP := { id MAP_ID \| pinned FILE }
c642ea26	37	\| DATA := { [hex] BYTES }
2148481d	38	\| PROG := { id PROG_ID \| pinned FILE \| tag PROG_TAG }
c642ea26	39	\| VALUE := { DATA \| MAP \| PROG }
47ff7ac6	40	\| UPDATE_FLAGS := { any \| exist \| noexist }
0b592b5a JK	41	\| TYPE := { hash \| array \| prog_array \| perf_event_array \| percpu_hash
	42	\| \| percpu_array \| stack_trace \| cgroup_array \| lru_hash
	43	\| \| lru_percpu_hash \| lpm_trie \| array_of_maps \| hash_of_maps
	44	\| \| devmap \| sockmap \| cpumap \| xskmap \| sockhash
	45	\| \| cgroup_storage \| reuseport_sockarray \| percpu_cgroup_storage }
ff69c21a JK	46
	47	DESCRIPTION
	48	===========
6ebe6dbd	49	bpftool map { show \| list } [MAP]
ff69c21a JK	50	Show information about loaded maps. If MAP is specified
	51	show information only about given map, otherwise list all
	52	maps currently loaded on the system.
	53
	54	Output will start with map ID followed by map type and
	55	zero or more named attributes (depending on kernel version).
	56
0b592b5a JK	57	bpftool map create FILE type TYPE key KEY_SIZE value VALUE_SIZE entries MAX_ENTRIES name NAME [flags FLAGS] [dev NAME]
	58	Create a new map with given parameters and pin it to bpffs
	59	as FILE.
	60
ff69c21a JK	61	bpftool map dump MAP
	62	Dump all entries in a given MAP.
	63
c642ea26	64	bpftool map update MAP key DATA value VALUE [UPDATE_FLAGS]
ff69c21a JK	65	Update map entry for a given KEY.
	66
	67	UPDATE_FLAGS can be one of: any update existing entry
	68	or add if doesn't exit; exist update only if entry already
	69	exists; noexist update only if entry doesn't exist.
	70
0c90f224 QM	71	If the hex keyword is provided in front of the bytes
	72	sequence, the bytes are parsed as hexadeximal values, even if
	73	no "0x" prefix is added. If the keyword is not provided, then
	74	the bytes are parsed as decimal values, unless a "0x" prefix
	75	(for hexadecimal) or a "0" prefix (for octal) is provided.
	76
c642ea26	77	bpftool map lookup MAP key DATA
ff69c21a JK	78	Lookup key in the map.
ff69c21a JK	79
c642ea26	80	bpftool map getnext MAP [key DATA]
ff69c21a JK	81	Get next key. If key is not specified, get first key.
ff69c21a JK	82
c642ea26	83	bpftool map delete MAP key DATA
ff69c21a JK	84	Remove entry from the map.
	85
	86	bpftool map pin MAP FILE
	87	Pin map MAP as FILE.
	88
882731e0 QM	89	Note: FILE must be located in bpffs mount. It must not
	90	contain a dot character ('.'), which is reserved for future
	91	extensions of bpffs.
ff69c21a	92
f412eed9 JK	93	bpftool map event_pipe MAP [cpu N index M]
	94	Read events from a BPF_MAP_TYPE_PERF_EVENT_ARRAY map.
	95
	96	Install perf rings into a perf event array map and dump
	97	output of any bpf_perf_event_output() call in the kernel.
	98	By default read the number of CPUs on the system and
	99	install perf ring for each CPU in the corresponding index
	100	in the array.
	101
	102	If cpu and index are specified, install perf ring
	103	for given cpu at index in the array (single ring).
	104
	105	Note that installing a perf ring into an array will silently
	106	replace any existing ring. Any other application will stop
	107	receiving events if it installed its rings earlier.
	108
ff69c21a JK	109	bpftool map help
	110	Print short help message.
	111
a2bc2e5c QM	112	OPTIONS
	113	=======
	114	-h, --help
	115	Print short generic help message (similar to bpftool help).
	116
	117	-v, --version
	118	Print version number (similar to bpftool version).
	119
0641c3c8 QM	120	-j, --json
	121	Generate JSON output. For commands that cannot produce JSON, this
	122	option has no effect.
	123
	124	-p, --pretty
	125	Generate human-readable JSON output. Implies -j.
	126
c541b734 PB	127	-f, --bpffs
	128	Show file names of pinned maps.
	129
ff69c21a JK	130	EXAMPLES
	131	========
	132	# bpftool map show
	133	::
	134
	135	10: hash name some_map flags 0x0
	136	key 4B value 8B max_entries 2048 memlock 167936B
	137
0c90f224 QM	138	The following three commands are equivalent:
	139
	140	\|
	141	\| # bpftool map update id 10 key hex 20 c4 b7 00 value hex 0f ff ff ab 01 02 03 4c
	142	\| # bpftool map update id 10 key 0x20 0xc4 0xb7 0x00 value 0x0f 0xff 0xff 0xab 0x01 0x02 0x03 0x4c
	143	\| # bpftool map update id 10 key 32 196 183 0 value 15 255 255 171 1 2 3 76
ff69c21a JK	144
	145	# bpftool map lookup id 10 key 0 1 2 3
	146
	147	::
	148
	149	key: 00 01 02 03 value: 00 01 02 03 04 05 06 07
	150
	151
	152	# bpftool map dump id 10
	153	::
	154
	155	key: 00 01 02 03 value: 00 01 02 03 04 05 06 07
	156	key: 0d 00 07 00 value: 02 00 00 00 01 02 03 04
	157	Found 2 elements
	158
	159	# bpftool map getnext id 10 key 0 1 2 3
	160	::
	161
	162	key:
	163	00 01 02 03
	164	next key:
	165	0d 00 07 00
	166
	167	\|
	168	\| # mount -t bpf none /sys/fs/bpf/
	169	\| # bpftool map pin id 10 /sys/fs/bpf/map
	170	\| # bpftool map del pinned /sys/fs/bpf/map key 13 00 07 00
	171
	172	SEE ALSO
	173	========
f98e46a2 QM	174	bpf\ (2),
	175	bpf-helpers\ (7),
	176	bpftool\ (8),
	177	bpftool-prog\ (8),
	178	bpftool-cgroup\ (8),
	179	bpftool-net\ (8),
	180	bpftool-perf\ (8)