[PATCH bpf-next v1 3/7] tools: bpftool: create map of maps
From: Alban Crequy
Date: Wed Mar 20 2019 - 13:35:05 EST
From: Alban Crequy <alban@xxxxxxxxxx>
Before this patch, there was no way to fill attr.inner_map_fd, necessary
for array_of_maps or hash_of_maps.
This patch adds keyword 'innermap' to pass the innermap, either as an id
or as a pinned map.
Example of commands:
$ sudo bpftool map create /sys/fs/bpf/innermap type hash \
key 8 value 8 entries 64 name innermap flags 1
$ sudo bpftool map create /sys/fs/bpf/outermap type hash_of_maps \
innermap pinned /sys/fs/bpf/innermap key 64 value 4 \
entries 64 name myoutermap flags 1
$ sudo bpftool map show pinned /sys/fs/bpf/outermap
47: hash_of_maps name myoutermap flags 0x1
key 64B value 4B max_entries 64 memlock 12288B
Documentation and bash completion updated as well.
Signed-off-by: Alban Crequy <alban@xxxxxxxxxx>
---
Previous version of this patch was sent while bpf-next was closed.
https://marc.info/?l=linux-kernel&m=155180393501258&w=2
Since then, the following changes were done:
- error management when calling map_parse_fd (review from Jakub)
- fix documentation and bash completion (review from Quentin)
---
.../bpf/bpftool/Documentation/bpftool-map.rst | 9 ++-
tools/bpf/bpftool/bash-completion/bpftool | 9 +++
tools/bpf/bpftool/map.c | 75 +++++++++++++++++--
3 files changed, 83 insertions(+), 10 deletions(-)
diff --git a/tools/bpf/bpftool/Documentation/bpftool-map.rst b/tools/bpf/bpftool/Documentation/bpftool-map.rst
index 5c984ffc9f01..b685641bfd74 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-map.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-map.rst
@@ -23,7 +23,7 @@ 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*]
+| **entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**dev** *NAME*] [**innermap** MAP]
| **bpftool** **map dump** *MAP*
| **bpftool** **map update** *MAP* [**key** *DATA*] [**value** *VALUE*] [*UPDATE_FLAGS*]
| **bpftool** **map lookup** *MAP* [**key** *DATA*]
@@ -60,10 +60,15 @@ DESCRIPTION
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*]
+ **bpftool map create** *FILE* **type** *TYPE* **key** *KEY_SIZE* **value** *VALUE_SIZE* **entries** *MAX_ENTRIES* **name** *NAME* [**flags** *FLAGS*] [**dev** *NAME*] [**innermap** MAP]
Create a new map with given parameters and pin it to *bpffs*
as *FILE*.
+ To create a map of type **array_of_maps** or
+ **hash_of_maps**, the additional parameter **innermap** needs
+ to reference an existing map with the type and size of the
+ maps in the values.
+
**bpftool map dump** *MAP*
Dump all entries in a given *MAP*.
diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool
index b803827d01e8..9e37de8bb227 100644
--- a/tools/bpf/bpftool/bash-completion/bpftool
+++ b/tools/bpf/bpftool/bash-completion/bpftool
@@ -461,6 +461,14 @@ _bpftool()
_sysfs_get_netdevs
return 0
;;
+ innermap)
+ COMPREPLY+=( $( compgen -W "id pinned" -- "$cur" ) )
+ return 0
+ ;;
+ id)
+ _bpftool_get_map_ids
+ return 0
+ ;;
*)
_bpftool_once_attr 'type'
_bpftool_once_attr 'key'
@@ -469,6 +477,7 @@ _bpftool()
_bpftool_once_attr 'name'
_bpftool_once_attr 'flags'
_bpftool_once_attr 'dev'
+ _bpftool_once_attr 'innermap'
return 0
;;
esac
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 18f9bc3aed4f..a576f2a019be 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -1100,6 +1100,7 @@ static int do_create(int argc, char **argv)
struct bpf_create_map_attr attr = { NULL, };
const char *pinfile;
int err, fd;
+ int inner_map_fd = -1;
if (!REQ_ARGS(7))
return -1;
@@ -1108,48 +1109,75 @@ static int do_create(int argc, char **argv)
while (argc) {
if (is_prefix(*argv, "type")) {
NEXT_ARG();
- if (!REQ_ARGS(1))
+ if (!REQ_ARGS(1)) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
+ }
if (attr.map_type) {
p_err("map type already specified");
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
}
attr.map_type = map_type_from_str(*argv);
if ((int)attr.map_type < 0) {
p_err("unrecognized map type: %s", *argv);
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
}
NEXT_ARG();
} else if (is_prefix(*argv, "name")) {
NEXT_ARG();
- if (!REQ_ARGS(1))
+ if (!REQ_ARGS(1)) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
+ }
attr.name = GET_ARG();
} else if (is_prefix(*argv, "key")) {
if (parse_u32_arg(&argc, &argv, &attr.key_size,
- "key size"))
+ "key size")) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
+ }
} else if (is_prefix(*argv, "value")) {
if (parse_u32_arg(&argc, &argv, &attr.value_size,
- "value size"))
+ "value size")) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
+ }
} else if (is_prefix(*argv, "entries")) {
if (parse_u32_arg(&argc, &argv, &attr.max_entries,
- "max entries"))
+ "max entries")) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
+ }
} else if (is_prefix(*argv, "flags")) {
if (parse_u32_arg(&argc, &argv, &attr.map_flags,
- "flags"))
+ "flags")) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
+ }
} else if (is_prefix(*argv, "dev")) {
NEXT_ARG();
- if (!REQ_ARGS(1))
+ if (!REQ_ARGS(1)) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
+ }
if (attr.map_ifindex) {
p_err("offload device already specified");
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
}
@@ -1157,28 +1185,59 @@ static int do_create(int argc, char **argv)
if (!attr.map_ifindex) {
p_err("unrecognized netdevice '%s': %s",
*argv, strerror(errno));
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
}
NEXT_ARG();
+ } else if (is_prefix(*argv, "innermap")) {
+ NEXT_ARG();
+ if (!REQ_ARGS(1)) {
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
+ return -1;
+ }
+
+ if (inner_map_fd != -1) {
+ close(inner_map_fd);
+ p_err("innermap already specified");
+ return -1;
+ }
+
+ inner_map_fd = map_parse_fd(&argc, &argv);
+ if (inner_map_fd < 0)
+ return -1;
} else {
p_err("unknown arg %s", *argv);
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
}
}
if (!attr.name) {
p_err("map name not specified");
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
}
set_max_rlimit();
+ if (inner_map_fd != -1)
+ attr.inner_map_fd = inner_map_fd;
+
fd = bpf_create_map_xattr(&attr);
if (fd < 0) {
p_err("map create failed: %s", strerror(errno));
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
return -1;
}
+ if (inner_map_fd != -1)
+ close(inner_map_fd);
+
err = do_pin_fd(fd, pinfile);
close(fd);
if (err)
@@ -1243,7 +1302,7 @@ static int do_help(int argc, char **argv)
"Usage: %s %s { show | list } [MAP]\n"
" %s %s create FILE type TYPE key KEY_SIZE value VALUE_SIZE \\\n"
" entries MAX_ENTRIES name NAME [flags FLAGS] \\\n"
- " [dev NAME]\n"
+ " [dev NAME] [innermap MAP]\n"
" %s %s dump MAP\n"
" %s %s update MAP [key DATA] [value VALUE] [UPDATE_FLAGS]\n"
" %s %s lookup MAP [key DATA]\n"
--
2.20.1