Commit 37b7c058 authored by Alexei Starovoitov's avatar Alexei Starovoitov
Browse files

Merge branch 'bpftool-net-attach' 



Daniel T. Lee says:

====================
Currently, bpftool net only supports dumping progs attached on the
interface. To attach XDP prog on interface, user must use other tool
(eg. iproute2). By this patch, with `bpftool net attach/detach`, user
can attach/detach XDP prog on interface.

    # bpftool prog
        16: xdp  name xdp_prog1  tag 539ec6ce11b52f98  gpl
        loaded_at 2019-08-07T08:30:17+0900  uid 0
        ...
        20: xdp  name xdp_fwd_prog  tag b9cb69f121e4a274  gpl
        loaded_at 2019-08-07T08:30:17+0900  uid 0

    # bpftool net attach xdpdrv id 16 dev enp6s0np0
    # bpftool net
    xdp:
        enp6s0np0(4) driver id 16

    # bpftool net attach xdpdrv id 20 dev enp6s0np0 overwrite
    # bpftool net
    xdp:
        enp6s0np0(4) driver id 20

    # bpftool net detach xdpdrv dev enp6s0np0
    # bpftool net
    xdp:

While this patch only contains support for XDP, through `net
attach/detach`, bpftool can further support other prog attach types.

XDP attach/detach tested on Mellanox ConnectX-4 and Netronome Agilio.

---
Changes in v5:
  - fix wrong error message, from errno to err with do_attach/detach

Changes in v4:
  - rename variable, attach/detach error message enhancement
  - bash-completion cleanup, doc update with brief description (attach
    types)

Changes in v3:
  - added 'overwrite' option for replacing previously attached XDP prog
  - command argument order has been changed ('ATTACH_TYPE' comes first)
  - add 'dev' keyword in front of <devname>
  - added bash-completion and documentation

Changes in v2:
  - command 'load/unload' changed to 'attach/detach' for the consistency
====================

Reviewed-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parents a9436dca cb9d9968

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

+54 −3
Original line number Diff line number Diff line
@@ -15,17 +15,22 @@ SYNOPSIS 
	*OPTIONS* := { [{ **-j** | **--json** }] [{ **-p** | **--pretty** }] }



	*COMMANDS* :=

	{ **show** | **list** } [ **dev** name ] | **help**

	{ **show** | **list** | **attach** | **detach** | **help** }



NET COMMANDS

============



|	**bpftool** **net { show | list } [ dev name ]**

|	**bpftool** **net { show | list }** [ **dev** *NAME* ]

|	**bpftool** **net attach** *ATTACH_TYPE* *PROG* **dev** *NAME* [ **overwrite** ]

|	**bpftool** **net detach** *ATTACH_TYPE* **dev** *NAME*

|	**bpftool** **net help**

|

|	*PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }

|	*ATTACH_TYPE* := { **xdp** | **xdpgeneric** | **xdpdrv** | **xdpoffload** }



DESCRIPTION

===========

	**bpftool net { show | list } [ dev name ]**

	**bpftool net { show | list }** [ **dev** *NAME* ]

                  List bpf program attachments in the kernel networking subsystem.



                  Currently, only device driver xdp attachments and tc filter
@@ -47,6 +52,24 @@ DESCRIPTION 
                  all bpf programs attached to non clsact qdiscs, and finally all

                  bpf programs attached to root and clsact qdisc.



	**bpftool** **net attach** *ATTACH_TYPE* *PROG* **dev** *NAME* [ **overwrite** ]

                  Attach bpf program *PROG* to network interface *NAME* with

                  type specified by *ATTACH_TYPE*. Previously attached bpf program

                  can be replaced by the command used with **overwrite** option.

                  Currently, only XDP-related modes are supported for *ATTACH_TYPE*.



                  *ATTACH_TYPE* can be of:

                  **xdp** - try native XDP and fallback to generic XDP if NIC driver does not support it;

                  **xdpgeneric** - Generic XDP. runs at generic XDP hook when packet already enters receive path as skb;

                  **xdpdrv** - Native XDP. runs earliest point in driver's receive path;

                  **xdpoffload** - Offload XDP. runs directly on NIC on each packet reception;



	**bpftool** **net detach** *ATTACH_TYPE* **dev** *NAME*

                  Detach bpf program attached to network interface *NAME* with

                  type specified by *ATTACH_TYPE*. To detach bpf program, same

                  *ATTACH_TYPE* previously used for attach must be specified.

                  Currently, only XDP-related modes are supported for *ATTACH_TYPE*.



	**bpftool net help**

		  Print short help message.
@@ -137,6 +160,34 @@ EXAMPLES 
        }

    ]



|

| **# bpftool net attach xdpdrv id 16 dev enp6s0np0**

| **# bpftool net**



::



      xdp:

      enp6s0np0(4) driver id 16



|

| **# bpftool net attach xdpdrv id 16 dev enp6s0np0**

| **# bpftool net attach xdpdrv id 20 dev enp6s0np0 overwrite**

| **# bpftool net**



::



      xdp:

      enp6s0np0(4) driver id 20



|

| **# bpftool net attach xdpdrv id 16 dev enp6s0np0**

| **# bpftool net detach xdpdrv dev enp6s0np0**

| **# bpftool net**



::



      xdp:





SEE ALSO

========

tools/bpf/bpftool/bash-completion/bpftool

+55 −10
Original line number Diff line number Diff line
@@ -201,6 +201,10 @@ _bpftool() 
            _bpftool_get_prog_tags

            return 0

            ;;

        dev)

            _sysfs_get_netdevs

            return 0

            ;;

        file|pinned)

            _filedir

            return 0
@@ -399,10 +403,6 @@ _bpftool() 
                            _filedir

                            return 0

                            ;;

                        dev)

                            _sysfs_get_netdevs

                            return 0

                            ;;

                        *)

                            COMPREPLY=( $( compgen -W "map" -- "$cur" ) )

                            _bpftool_once_attr 'type'
@@ -498,10 +498,6 @@ _bpftool() 
                        key|value|flags|name|entries)

                            return 0

                            ;;

                        dev)

                            _sysfs_get_netdevs

                            return 0

                            ;;

                        *)

                            _bpftool_once_attr 'type'

                            _bpftool_once_attr 'key'
@@ -778,18 +774,67 @@ _bpftool() 
            esac

            ;;

        net)

            local PROG_TYPE='id pinned tag'

            local ATTACH_TYPES='xdp xdpgeneric xdpdrv xdpoffload'

            case $command in

                show|list)

                    [[ $prev != "$command" ]] && return 0

                    COMPREPLY=( $( compgen -W 'dev' -- "$cur" ) )

                    return 0

                    ;;

                attach)

                    case $cword in

                        3)

                            COMPREPLY=( $( compgen -W "$ATTACH_TYPES" -- "$cur" ) )

                            return 0

                            ;;

                        4)

                            COMPREPLY=( $( compgen -W "$PROG_TYPE" -- "$cur" ) )

                            return 0

                            ;;

                        5)

                            case $prev in

                                id)

                                    _bpftool_get_prog_ids

                                    ;;

                                pinned)

                                    _filedir

                                    ;;

                            esac

                            return 0

                            ;;

                        6)

                            COMPREPLY=( $( compgen -W 'dev' -- "$cur" ) )

                            return 0

                            ;;

                        8)

                            _bpftool_once_attr 'overwrite'

                            return 0

                            ;;

                    esac

                    ;;

                detach)

                    case $cword in

                        3)

                            COMPREPLY=( $( compgen -W "$ATTACH_TYPES" -- "$cur" ) )

                            return 0

                            ;;

                        4)

                            COMPREPLY=( $( compgen -W 'dev' -- "$cur" ) )

                            return 0

                            ;;

                    esac

                    ;;

                *)

                    [[ $prev == $object ]] && \

                        COMPREPLY=( $( compgen -W 'help \

                            show list' -- "$cur" ) )

                            show list attach detach' -- "$cur" ) )

                    ;;

            esac

            ;;

        feature)

            case $command in

                probe)

                    [[ $prev == "dev" ]] && _sysfs_get_netdevs && return 0

                    [[ $prev == "prefix" ]] && return 0

                    if _bpftool_search_list 'macros'; then

                        COMPREPLY+=( $( compgen -W 'prefix' -- "$cur" ) )

tools/bpf/bpftool/net.c

+169 −7
Original line number Diff line number Diff line
@@ -55,6 +55,35 @@ struct bpf_attach_info { 
	__u32 flow_dissector_id;

};



enum net_attach_type {

	NET_ATTACH_TYPE_XDP,

	NET_ATTACH_TYPE_XDP_GENERIC,

	NET_ATTACH_TYPE_XDP_DRIVER,

	NET_ATTACH_TYPE_XDP_OFFLOAD,

};



static const char * const attach_type_strings[] = {

	[NET_ATTACH_TYPE_XDP]		= "xdp",

	[NET_ATTACH_TYPE_XDP_GENERIC]	= "xdpgeneric",

	[NET_ATTACH_TYPE_XDP_DRIVER]	= "xdpdrv",

	[NET_ATTACH_TYPE_XDP_OFFLOAD]	= "xdpoffload",

};



const size_t net_attach_type_size = ARRAY_SIZE(attach_type_strings);



static enum net_attach_type parse_attach_type(const char *str)

{

	enum net_attach_type type;



	for (type = 0; type < net_attach_type_size; type++) {

		if (attach_type_strings[type] &&

		    is_prefix(str, attach_type_strings[type]))

			return type;

	}



	return net_attach_type_size;

}



static int dump_link_nlmsg(void *cookie, void *msg, struct nlattr **tb)

{

	struct bpf_netdev_t *netinfo = cookie;
@@ -223,6 +252,134 @@ static int query_flow_dissector(struct bpf_attach_info *attach_info) 
	return 0;

}



static int net_parse_dev(int *argc, char ***argv)

{

	int ifindex;



	if (is_prefix(**argv, "dev")) {

		NEXT_ARGP();



		ifindex = if_nametoindex(**argv);

		if (!ifindex)

			p_err("invalid devname %s", **argv);



		NEXT_ARGP();

	} else {

		p_err("expected 'dev', got: '%s'?", **argv);

		return -1;

	}



	return ifindex;

}



static int do_attach_detach_xdp(int progfd, enum net_attach_type attach_type,

				int ifindex, bool overwrite)

{

	__u32 flags = 0;



	if (!overwrite)

		flags = XDP_FLAGS_UPDATE_IF_NOEXIST;

	if (attach_type == NET_ATTACH_TYPE_XDP_GENERIC)

		flags |= XDP_FLAGS_SKB_MODE;

	if (attach_type == NET_ATTACH_TYPE_XDP_DRIVER)

		flags |= XDP_FLAGS_DRV_MODE;

	if (attach_type == NET_ATTACH_TYPE_XDP_OFFLOAD)

		flags |= XDP_FLAGS_HW_MODE;



	return bpf_set_link_xdp_fd(ifindex, progfd, flags);

}



static int do_attach(int argc, char **argv)

{

	enum net_attach_type attach_type;

	int progfd, ifindex, err = 0;

	bool overwrite = false;



	/* parse attach args */

	if (!REQ_ARGS(5))

		return -EINVAL;



	attach_type = parse_attach_type(*argv);

	if (attach_type == net_attach_type_size) {

		p_err("invalid net attach/detach type: %s", *argv);

		return -EINVAL;

	}

	NEXT_ARG();



	progfd = prog_parse_fd(&argc, &argv);

	if (progfd < 0)

		return -EINVAL;



	ifindex = net_parse_dev(&argc, &argv);

	if (ifindex < 1) {

		close(progfd);

		return -EINVAL;

	}



	if (argc) {

		if (is_prefix(*argv, "overwrite")) {

			overwrite = true;

		} else {

			p_err("expected 'overwrite', got: '%s'?", *argv);

			close(progfd);

			return -EINVAL;

		}

	}



	/* attach xdp prog */

	if (is_prefix("xdp", attach_type_strings[attach_type]))

		err = do_attach_detach_xdp(progfd, attach_type, ifindex,

					   overwrite);



	if (err < 0) {

		p_err("interface %s attach failed: %s",

		      attach_type_strings[attach_type], strerror(-err));

		return err;

	}



	if (json_output)

		jsonw_null(json_wtr);



	return 0;

}



static int do_detach(int argc, char **argv)

{

	enum net_attach_type attach_type;

	int progfd, ifindex, err = 0;



	/* parse detach args */

	if (!REQ_ARGS(3))

		return -EINVAL;



	attach_type = parse_attach_type(*argv);

	if (attach_type == net_attach_type_size) {

		p_err("invalid net attach/detach type: %s", *argv);

		return -EINVAL;

	}

	NEXT_ARG();



	ifindex = net_parse_dev(&argc, &argv);

	if (ifindex < 1)

		return -EINVAL;



	/* detach xdp prog */

	progfd = -1;

	if (is_prefix("xdp", attach_type_strings[attach_type]))

		err = do_attach_detach_xdp(progfd, attach_type, ifindex, NULL);



	if (err < 0) {

		p_err("interface %s detach failed: %s",

		      attach_type_strings[attach_type], strerror(-err));

		return err;

	}



	if (json_output)

		jsonw_null(json_wtr);



	return 0;

}



static int do_show(int argc, char **argv)

{

	struct bpf_attach_info attach_info = {};
@@ -232,13 +389,9 @@ static int do_show(int argc, char **argv) 
	char err_buf[256];



	if (argc == 2) {

		if (strcmp(argv[0], "dev") != 0)

			usage();

		filter_idx = if_nametoindex(argv[1]);

		if (filter_idx == 0) {

			fprintf(stderr, "invalid dev name %s\n", argv[1]);

		filter_idx = net_parse_dev(&argc, &argv);

		if (filter_idx < 1)

			return -1;

		}

	} else if (argc != 0) {

		usage();

	}
@@ -305,13 +458,20 @@ static int do_help(int argc, char **argv) 


	fprintf(stderr,

		"Usage: %s %s { show | list } [dev <devname>]\n"

		"       %s %s attach ATTACH_TYPE PROG dev <devname> [ overwrite ]\n"

		"       %s %s detach ATTACH_TYPE dev <devname>\n"

		"       %s %s help\n"

		"\n"

		"       " HELP_SPEC_PROGRAM "\n"

		"       ATTACH_TYPE := { xdp | xdpgeneric | xdpdrv | xdpoffload }\n"

		"\n"

		"Note: Only xdp and tc attachments are supported now.\n"

		"      For progs attached to cgroups, use \"bpftool cgroup\"\n"

		"      to dump program attachments. For program types\n"

		"      sk_{filter,skb,msg,reuseport} and lwt/seg6, please\n"

		"      consult iproute2.\n",

		bin_name, argv[-2], bin_name, argv[-2]);

		bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],

		bin_name, argv[-2]);



	return 0;

}
@@ -319,6 +479,8 @@ static int do_help(int argc, char **argv) 
static const struct cmd cmds[] = {

	{ "show",	do_show },

	{ "list",	do_show },

	{ "attach",	do_attach },

	{ "detach",	do_detach },

	{ "help",	do_help },

	{ 0 }

};

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