Commit 7a279e93 authored by Quentin Monnet's avatar Quentin Monnet Committed by Daniel Borkmann
Browse files

bpf: clean up eBPF helpers documentation 



These are minor edits for the eBPF helpers documentation in
include/uapi/linux/bpf.h.

The main fix consists in removing "BPF_FIB_LOOKUP_", because it ends
with a non-escaped underscore that gets interpreted by rst2man and
produces the following message in the resulting manual page:

    DOCUTILS SYSTEM MESSAGES
           System Message: ERROR/3 (/tmp/bpf-helpers.rst:, line 1514)
                  Unknown target name: "bpf_fib_lookup".

Other edits consist in:

- Improving formatting for flag values for "bpf_fib_lookup()" helper.
- Emphasising a parameter name in description of the return value for
  "bpf_get_stack()" helper.
- Removing unnecessary blank lines between "Description" and "Return"
  sections for the few helpers that would use it, for consistency.

Signed-off-by: default avatarQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: default avatarSong Liu <songliubraving@fb.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent f198222f

include/uapi/linux/bpf.h

+10 −11
Original line number Diff line number Diff line
@@ -1010,7 +1010,6 @@ union bpf_attr { 
 * 		::

 *

 * 			# sysctl kernel.perf_event_max_stack=<new value>

 *

 * 	Return

 * 		The positive or null stack id on success, or a negative error

 * 		in case of failure.
@@ -1821,10 +1820,9 @@ union bpf_attr { 
 * 		::

 *

 * 			# sysctl kernel.perf_event_max_stack=<new value>

 *

 * 	Return

 * 		a non-negative value equal to or less than size on success, or

 * 		a negative error in case of failure.

 * 		A non-negative value equal to or less than *size* on success,

 * 		or a negative error in case of failure.

 *

 * int skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header)

 * 	Description
@@ -1845,7 +1843,6 @@ union bpf_attr { 
 * 		in socket filters where *skb*\ **->data** does not always point

 * 		to the start of the mac header and where "direct packet access"

 * 		is not available.

 *

 * 	Return

 * 		0 on success, or a negative error in case of failure.

 *
@@ -1861,16 +1858,18 @@ union bpf_attr { 
 *		rt_metric is set to metric from route.

 *

 *             *plen* argument is the size of the passed in struct.

 *             *flags* argument can be one or more BPF_FIB_LOOKUP_ flags:

 *             *flags* argument can be a combination of one or more of the

 *             following values:

 *

 *             **BPF_FIB_LOOKUP_DIRECT** means do a direct table lookup vs

 *             full lookup using FIB rules

 *             **BPF_FIB_LOOKUP_OUTPUT** means do lookup from an egress

 *             perspective (default is ingress)

 *		**BPF_FIB_LOOKUP_DIRECT**

 *			Do a direct table lookup vs full lookup using FIB

 *			rules.

 *		**BPF_FIB_LOOKUP_OUTPUT**

 *			Perform lookup from an egress perspective (default is

 *			ingress).

 *

 *             *ctx* is either **struct xdp_md** for XDP programs or

 *             **struct sk_buff** tc cls_act programs.

 *

 *     Return

 *             Egress device index on success, 0 if packet needs to continue

 *             up the stack for further processing or a negative error in case

tools/include/uapi/linux/bpf.h

+10 −11
Original line number Diff line number Diff line
@@ -1010,7 +1010,6 @@ union bpf_attr { 
 * 		::

 *

 * 			# sysctl kernel.perf_event_max_stack=<new value>

 *

 * 	Return

 * 		The positive or null stack id on success, or a negative error

 * 		in case of failure.
@@ -1821,10 +1820,9 @@ union bpf_attr { 
 * 		::

 *

 * 			# sysctl kernel.perf_event_max_stack=<new value>

 *

 * 	Return

 * 		a non-negative value equal to or less than size on success, or

 * 		a negative error in case of failure.

 * 		A non-negative value equal to or less than *size* on success,

 * 		or a negative error in case of failure.

 *

 * int skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header)

 * 	Description
@@ -1845,7 +1843,6 @@ union bpf_attr { 
 * 		in socket filters where *skb*\ **->data** does not always point

 * 		to the start of the mac header and where "direct packet access"

 * 		is not available.

 *

 * 	Return

 * 		0 on success, or a negative error in case of failure.

 *
@@ -1861,16 +1858,18 @@ union bpf_attr { 
 *		rt_metric is set to metric from route.

 *

 *             *plen* argument is the size of the passed in struct.

 *             *flags* argument can be one or more BPF_FIB_LOOKUP_ flags:

 *             *flags* argument can be a combination of one or more of the

 *             following values:

 *

 *             **BPF_FIB_LOOKUP_DIRECT** means do a direct table lookup vs

 *             full lookup using FIB rules

 *             **BPF_FIB_LOOKUP_OUTPUT** means do lookup from an egress

 *             perspective (default is ingress)

 *		**BPF_FIB_LOOKUP_DIRECT**

 *			Do a direct table lookup vs full lookup using FIB

 *			rules.

 *		**BPF_FIB_LOOKUP_OUTPUT**

 *			Perform lookup from an egress perspective (default is

 *			ingress).

 *

 *             *ctx* is either **struct xdp_md** for XDP programs or

 *             **struct sk_buff** tc cls_act programs.

 *

 *     Return

 *             Egress device index on success, 0 if packet needs to continue

 *             up the stack for further processing or a negative error in case

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