15 helpersDocStart = 'Start of BPF helper function descriptions:'
46 class Helper(APIElement):  class
48     An object representing the description of an eBPF helper function.
49     @proto: function prototype of the helper function
50     @desc: textual description of the helper function
51     @ret: description of the return value of the helper function
59         Break down helper function protocol into smaller chunks: return type,
87     list of eBPF helper functions. All the helpers that can be retrieved are
88     stored as Helper object, in the self.helpers() array.
113         return Helper(proto=proto, desc=desc, ret=ret)
245                      'Could not find start of eBPF helper descriptions list')
248                 helper = self.parse_helper()
249                 self.helpers.append(helper)
250                 proto = helper.proto_break_down()
262                      'Could not find start of eBPF helper definition list')
281         for helper in self.helpers:
282             proto = helper.proto_break_down()
287                 raise Exception("Helper %s is missing from enum bpf_func_id" % name)
294 …raise Exception("Helper %s comment order (#%d) must be aligned with its position (#%d) in enum bpf…
296             helper.enum_val = enum_val
311     Helper objects, and implement a way to print them in the desired fashion.
324     def print_one(self, helper):  argument
346                 # Function description is parsed until no helper is found (which can be due to
347                 # misformatting). Hence, only print the first missing/misformatted helper/enum.
422     @parser: A HeaderParser with Helper objects to print to standard output
426 …self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '__BPF_…
434 list of eBPF helper functions
459 Due to eBPF conventions, a helper can not have more than five arguments.
461 Internally, eBPF programs call directly into the compiled helper functions
497 as "Dual BSD/GPL", may be used). Some helper functions are only accessible to
512 This manual page is an effort to document the existing eBPF helper functions.
514 program or map types are added, along with new helper functions. Some helpers
517 check by yourself what helper functions exist in your kernel, or what types of
522   of all helper functions, as well as many other BPF definitions including most
524 * *net/core/filter.c* contains the definition of most network-related helper
529   of eBPF maps are used with a given helper function.
532 * The bpftool utility can be used to probe the availability of helper functions
538 Compatibility between helper functions and program types can generally be found
539 in the files where helper functions are defined. Look for the **struct
546 Compatibility between helper functions and map types can be found in the
549 Helper functions that invalidate the checks on **data** and **data_end**
566     def print_proto(self, helper):  argument
571         proto = helper.proto_break_down()
592     def print_one(self, helper):  argument
593         self.print_proto(helper)
594         self.print_elem(helper)
635     @parser: A HeaderParser with Helper objects to print to standard output
639 …self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '__BPF_…
786     def print_one(self, helper):  argument
787         proto = helper.proto_break_down()
796         if (helper.desc):
799             for line in re.sub('\n$', '', helper.desc, count=1).split('\n'):
802         if (helper.ret):
805             for line in helper.ret.rstrip().split('\n'):
828         print(') = (void *) %d;' % helper.enum_val)