25 class Helper(object):  class
27     An object representing the description of an eBPF helper function.
28     @proto: function prototype of the helper function
29     @desc: textual description of the helper function
30     @ret: description of the return value of the helper function
39         Break down helper function protocol into smaller chunks: return type,
66     list of eBPF helper functions. All the helpers that can be retrieved are
67     stored as Helper object, in the self.helpers() array.
80         return Helper(proto=proto, desc=desc, ret=ret)
101             # Helper can have empty description and we might be parsing another
124             # Helper can have empty retval and we might be parsing another
144         # Advance to start of helper function descriptions.
145         offset = self.reader.read().find('* Start of BPF helper function descriptions:')
147             raise Exception('Could not find start of eBPF helper descriptions list')
155                 helper = self.parse_helper()
156                 self.helpers.append(helper)
161         print('Parsed description of %d helper function(s)' % len(self.helpers),
169     Helper objects, and implement a way to print them in the desired fashion.
170     @helpers: array of Helper objects to print to standard output
181     def print_one(self, helper):  argument
186         for helper in self.helpers:
187             self.print_one(helper)
195     @helpers: array of Helper objects to print to standard output
233 list of eBPF helper functions
256 Due to eBPF conventions, a helper can not have more than five arguments.
258 Internally, eBPF programs call directly into the compiled helper functions
288 as "Dual BSD/GPL", may be used). Some helper functions are only accessible to
303 This manual page is an effort to document the existing eBPF helper functions.
305 program or map types are added, along with new helper functions. Some helpers
308 check by yourself what helper functions exist in your kernel, or what types of
313   of all helper functions, as well as many other BPF definitions including most
315 * *net/core/filter.c* contains the definition of most network-related helper
320   of eBPF maps are used with a given helper function.
324 Compatibility between helper functions and program types can generally be found
325 in the files where helper functions are defined. Look for the **struct
332 Compatibility between helper functions and map types can be found in the
335 Helper functions that invalidate the checks on **data** and **data_end**
351     def print_proto(self, helper):  argument
356         proto = helper.proto_break_down()
377     def print_one(self, helper):  argument
378         self.print_proto(helper)
380         if (helper.desc):
384             for line in re.sub('\n$', '', helper.desc, count=1).split('\n'):
387         if (helper.ret):
389             for line in helper.ret.rstrip().split('\n'):
404 Parse eBPF header file and generate documentation for eBPF helper functions.