import argparse
import re
import sys, os
+import subprocess
+
+helpersDocStart = 'Start of BPF helper function descriptions:'
class NoHelperFound(BaseException):
pass
@desc: textual description of the helper function
@ret: description of the return value of the helper function
"""
+ def __init__(self, *args, **kwargs):
+ super().__init__(*args, **kwargs)
+ self.enum_val = None
+
def proto_break_down(self):
"""
Break down helper function protocol into smaller chunks: return type,
self.commands = []
self.desc_unique_helpers = set()
self.define_unique_helpers = []
+ self.helper_enum_vals = {}
+ self.helper_enum_pos = {}
self.desc_syscalls = []
self.enum_syscalls = []
self.enum_syscalls = re.findall('(BPF\w+)+', bpf_cmd_str)
def parse_desc_helpers(self):
- self.seek_to('* Start of BPF helper function descriptions:',
+ self.seek_to(helpersDocStart,
'Could not find start of eBPF helper descriptions list')
while True:
try:
break
def parse_define_helpers(self):
- # Parse the number of FN(...) in #define __BPF_FUNC_MAPPER to compare
- # later with the number of unique function names present in description.
+ # Parse FN(...) in #define ___BPF_FUNC_MAPPER to compare later with the
+ # number of unique function names present in description and use the
+ # correct enumeration value.
# Note: seek_to(..) discards the first line below the target search text,
- # resulting in FN(unspec) being skipped and not added to self.define_unique_helpers.
- self.seek_to('#define __BPF_FUNC_MAPPER(FN)',
+ # resulting in FN(unspec, 0, ##ctx) being skipped and not added to
+ # self.define_unique_helpers.
+ self.seek_to('#define ___BPF_FUNC_MAPPER(FN, ctx...)',
'Could not find start of eBPF helper definition list')
- # Searches for either one or more FN(\w+) defines or a backslash for newline
- p = re.compile('\s*(FN\(\w+\))+|\\\\')
+ # Searches for one FN(\w+) define or a backslash for newline
+ p = re.compile('\s*FN\((\w+), (\d+), ##ctx\)|\\\\')
fn_defines_str = ''
+ i = 0
while True:
capture = p.match(self.line)
if capture:
fn_defines_str += self.line
+ helper_name = capture.expand(r'bpf_\1')
+ self.helper_enum_vals[helper_name] = int(capture[2])
+ self.helper_enum_pos[helper_name] = i
+ i += 1
else:
break
self.line = self.reader.readline()
# Find the number of occurences of FN(\w+)
- self.define_unique_helpers = re.findall('FN\(\w+\)', fn_defines_str)
+ self.define_unique_helpers = re.findall('FN\(\w+, \d+, ##ctx\)', fn_defines_str)
+
+ def validate_helpers(self):
+ last_helper = ''
+ seen_helpers = set()
+ seen_enum_vals = set()
+ i = 0
+ for helper in self.helpers:
+ proto = helper.proto_break_down()
+ name = proto['name']
+ try:
+ enum_val = self.helper_enum_vals[name]
+ enum_pos = self.helper_enum_pos[name]
+ except KeyError:
+ raise Exception("Helper %s is missing from enum bpf_func_id" % name)
+
+ if name in seen_helpers:
+ if last_helper != name:
+ raise Exception("Helper %s has multiple descriptions which are not grouped together" % name)
+ continue
+
+ # Enforce current practice of having the descriptions ordered
+ # by enum value.
+ if enum_pos != i:
+ raise Exception("Helper %s (ID %d) comment order (#%d) must be aligned with its position (#%d) in enum bpf_func_id" % (name, enum_val, i + 1, enum_pos + 1))
+ if enum_val in seen_enum_vals:
+ raise Exception("Helper %s has duplicated value %d" % (name, enum_val))
+
+ seen_helpers.add(name)
+ last_helper = name
+ seen_enum_vals.add(enum_val)
+
+ helper.enum_val = enum_val
+ i += 1
def run(self):
self.parse_desc_syscall()
self.parse_enum_syscall()
self.parse_desc_helpers()
self.parse_define_helpers()
+ self.validate_helpers()
self.reader.close()
###############################################################################
print('')
+ def get_kernel_version(self):
+ try:
+ version = subprocess.run(['git', 'describe'], cwd=linuxRoot,
+ capture_output=True, check=True)
+ version = version.stdout.decode().rstrip()
+ except:
+ try:
+ version = subprocess.run(['make', 'kernelversion'], cwd=linuxRoot,
+ capture_output=True, check=True)
+ version = version.stdout.decode().rstrip()
+ except:
+ return 'Linux'
+ return 'Linux {version}'.format(version=version)
+
+ def get_last_doc_update(self, delimiter):
+ try:
+ cmd = ['git', 'log', '-1', '--pretty=format:%cs', '--no-patch',
+ '-L',
+ '/{}/,/\*\//:include/uapi/linux/bpf.h'.format(delimiter)]
+ date = subprocess.run(cmd, cwd=linuxRoot,
+ capture_output=True, check=True)
+ return date.stdout.decode().rstrip()
+ except:
+ return ''
+
class PrinterHelpersRST(PrinterRST):
"""
A printer for dumping collected information about helpers as a ReStructured
"""
def __init__(self, parser):
self.elements = parser.helpers
- self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '__BPF_FUNC_MAPPER')
+ self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '___BPF_FUNC_MAPPER')
def print_header(self):
header = '''\
-------------------------------------------------------------------------------
:Manual section: 7
+:Version: {version}
+{date_field}{date}
DESCRIPTION
===========
HELPERS
=======
'''
+ kernelVersion = self.get_kernel_version()
+ lastUpdate = self.get_last_doc_update(helpersDocStart)
+
PrinterRST.print_license(self)
- print(header)
+ print(header.format(version=kernelVersion,
+ date_field = ':Date: ' if lastUpdate else '',
+ date=lastUpdate))
def print_footer(self):
footer = '''
"""
def __init__(self, parser):
self.elements = parser.helpers
- self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '__BPF_FUNC_MAPPER')
+ self.elem_number_check(parser.desc_unique_helpers, parser.define_unique_helpers, 'helper', '___BPF_FUNC_MAPPER')
type_fwds = [
'struct bpf_fib_lookup',
'struct udp6_sock',
'struct unix_sock',
'struct task_struct',
+ 'struct cgroup',
'struct __sk_buff',
'struct sk_msg_md',
'struct udp6_sock',
'struct unix_sock',
'struct task_struct',
+ 'struct cgroup',
'struct path',
'struct btf_ptr',
'struct inode',
'struct bpf_timer',
'struct mptcp_sock',
'struct bpf_dynptr',
+ 'const struct bpf_dynptr',
'struct iphdr',
'struct ipv6hdr',
}
comma = ', '
print(one_arg, end='')
- print(') = (void *) %d;' % len(self.seen_helpers))
+ print(') = (void *) %d;' % helper.enum_val)
print('')
###############################################################################
projects / linux.git / blobdiff