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.
114         return Helper(proto=proto, desc=desc, ret=ret)
246                      'Could not find start of eBPF helper descriptions list')
249                 helper = self.parse_helper()
250                 self.helpers.append(helper)
251                 proto = helper.proto_break_down()
264                      'Could not find start of eBPF helper definition list')
288         for helper in self.helpers:
289             proto = helper.proto_break_down()
295                 raise Exception("Helper %s is missing from enum bpf_func_id" % name)
299 …       raise Exception("Helper %s has multiple descriptions which are not grouped together" % name)
305 …raise Exception("Helper %s (ID %d) comment order (#%d) must be aligned with its position (#%d) in …
307                 raise Exception("Helper %s has duplicated value %d" % (name, enum_val))
313             helper.enum_val = enum_val
329     Helper objects, and implement a way to print them in the desired fashion.
342     def print_one(self, helper):  argument
364                 # Function description is parsed until no helper is found (which can be due to
365                 # misformatting). Hence, only print the first missing/misformatted helper/enum.
440     @parser: A HeaderParser with Helper objects to print to standard output
444 …self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '___BPF…
452 list of eBPF helper functions
477 Due to eBPF conventions, a helper can not have more than five arguments.
479 Internally, eBPF programs call directly into the compiled helper functions
515 as "Dual BSD/GPL", may be used). Some helper functions are only accessible to
530 This manual page is an effort to document the existing eBPF helper functions.
532 program or map types are added, along with new helper functions. Some helpers
535 check by yourself what helper functions exist in your kernel, or what types of
540   of all helper functions, as well as many other BPF definitions including most
542 * *net/core/filter.c* contains the definition of most network-related helper
547   of eBPF maps are used with a given helper function.
550 * The bpftool utility can be used to probe the availability of helper functions
556 Compatibility between helper functions and program types can generally be found
557 in the files where helper functions are defined. Look for the **struct
564 Compatibility between helper functions and map types can be found in the
567 Helper functions that invalidate the checks on **data** and **data_end**
584     def print_proto(self, helper):  argument
589         proto = helper.proto_break_down()
610     def print_one(self, helper):  argument
611         self.print_proto(helper)
612         self.print_elem(helper)
653     @parser: A HeaderParser with Helper objects to print to standard output
657 …self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '___BPF…
807     def print_one(self, helper):  argument
808         proto = helper.proto_break_down()
817         if (helper.desc):
820             for line in re.sub('\n$', '', helper.desc, count=1).split('\n'):
823         if (helper.ret):
826             for line in helper.ret.rstrip().split('\n'):
849         print(') = (void *) %d;' % helper.enum_val)