Files
littlefs/scripts/dbgmtree.py
Christopher Haster c1fe64314c Reworked how filesystem-level config is stored
Now, instead of storing a single contiguous block of config data, config
is stored as tagged metadata like any other attribute.

This allows more flexibility towards adding/removing config in the
future, without cluttering up the config with deprecated entries (see
ATA's "IDENTIFY DEVICE" response).

Most of the config entries are single leb128 limits on various integer
types, with the exception of the magic string and version (major/minor
pair).

---

Note this also includes some semantic changes to the config:

- Limits are stored as size-1. This avoid issues with integer overflow
  at extreme ranges.

  This was also adopted for block size (block limit) and block count
  (disk limit). This deviation between on-disk config and user-facing
  config risks confusion, but allows the potential for the full 2^31 range
  for these values.

- The default cksum type, crc32c, has been changed to 0.

  Originally this was 2 to allow the type to map to the crc width for
  crc8, crc16, crc32c, crc64, etc. But dropping this idea and numbering
  checksums as they are implemented simplifies things.

  May come back to this.

- Storing these configs as attributes opens up of the option of on-disk
  defaults when configs are missing.

  I'm being a bit conservative with this one, as it's not clear to me if
  we should prefer default configs (less code/storage, risk of untested
  config parsing) or prefer explicit on-disk configs.

  Currently the following have defaults since they seem the most obvious
  to me:

  - cksum type  => defaults to crc32c
  - redund type => defaults to parity (TODO, should this default to
    no redund?)
  - utag_limit  => defaults to 0x7f (no special tag decoding)
  - uattr_limit => defaults to block_limit (implicit)
2023-09-15 14:51:25 -05:00

1674 lines
60 KiB
Python
Executable File

#!/usr/bin/env python3
import bisect
import collections as co
import itertools as it
import math as m
import os
import struct
TAG_NULL = 0x0000
TAG_CONFIG = 0x0000
TAG_MAGIC = 0x0003
TAG_VERSION = 0x0004
TAG_FLAGS = 0x0005
TAG_CKSUMTYPE = 0x0006
TAG_REDUNDTYPE = 0x0007
TAG_BLOCKLIMIT = 0x0008
TAG_DISKLIMIT = 0x0009
TAG_MLEAFLIMIT = 0x000a
TAG_SIZELIMIT = 0x000b
TAG_NAMELIMIT = 0x000c
TAG_UTAGLIMIT = 0x000d
TAG_UATTRLIMIT = 0x000e
TAG_GSTATE = 0x0100
TAG_GRM = 0x0100
TAG_NAME = 0x0200
TAG_BRANCH = 0x0200
TAG_BOOKMARK = 0x0201
TAG_REG = 0x0202
TAG_DIR = 0x0203
TAG_STRUCT = 0x0300
TAG_INLINED = 0x0300
TAG_BLOCK = 0x0308
TAG_BTREE = 0x030c
TAG_MDIR = 0x0311
TAG_MTREE = 0x0314
TAG_MROOT = 0x0318
TAG_DID = 0x031c
TAG_UATTR = 0x0400
TAG_SATTR = 0x0500
TAG_ALT = 0x4000
TAG_CKSUM = 0x2000
TAG_ECKSUM = 0x2100
# parse some rbyd addr encodings
# 0xa -> [0xa]
# 0xa.b -> ([0xa], b)
# 0x{a,b} -> [0xa, 0xb]
def rbydaddr(s):
s = s.strip()
b = 10
if s.startswith('0x') or s.startswith('0X'):
s = s[2:]
b = 16
elif s.startswith('0o') or s.startswith('0O'):
s = s[2:]
b = 8
elif s.startswith('0b') or s.startswith('0B'):
s = s[2:]
b = 2
trunk = None
if '.' in s:
s, s_ = s.split('.', 1)
trunk = int(s_, b)
if s.startswith('{') and '}' in s:
ss = s[1:s.find('}')].split(',')
else:
ss = [s]
addr = []
for s in ss:
if trunk is not None:
addr.append((int(s, b), trunk))
else:
addr.append(int(s, b))
return addr
def crc32c(data, crc=0):
crc ^= 0xffffffff
for b in data:
crc ^= b
for j in range(8):
crc = (crc >> 1) ^ ((crc & 1) * 0x82f63b78)
return 0xffffffff ^ crc
def fromle32(data):
return struct.unpack('<I', data[0:4].ljust(4, b'\0'))[0]
def fromleb128(data):
word = 0
for i, b in enumerate(data):
word |= ((b & 0x7f) << 7*i)
word &= 0xffffffff
if not b & 0x80:
return word, i+1
return word, len(data)
def fromtag(data):
data = data.ljust(4, b'\0')
tag = (data[0] << 8) | data[1]
weight, d = fromleb128(data[2:])
size, d_ = fromleb128(data[2+d:])
return tag>>15, tag&0x7fff, weight, size, 2+d+d_
def frommdir(data):
blocks = []
d = 0
while d < len(data):
block, d_ = fromleb128(data[d:])
blocks.append(block)
d += d_
return blocks
def frombtree(data):
d = 0
block, d_ = fromleb128(data[d:]); d += d_
trunk, d_ = fromleb128(data[d:]); d += d_
w, d_ = fromleb128(data[d:]); d += d_
cksum = fromle32(data[d:]); d += 4
return block, trunk, w, cksum
def popc(x):
return bin(x).count('1')
def xxd(data, width=16):
for i in range(0, len(data), width):
yield '%-*s %-*s' % (
3*width,
' '.join('%02x' % b for b in data[i:i+width]),
width,
''.join(
b if b >= ' ' and b <= '~' else '.'
for b in map(chr, data[i:i+width])))
def tagrepr(tag, w, size, off=None):
if tag == TAG_NULL:
return 'null%s%s' % (
' w%d' % w if w else '',
' %d' % size if size else '')
elif (tag & 0xff00) == TAG_CONFIG:
return '%s%s %d' % (
'magic' if tag == TAG_MAGIC
else 'version' if tag == TAG_VERSION
else 'flags' if tag == TAG_FLAGS
else 'cksumtype' if tag == TAG_CKSUMTYPE
else 'redundtype' if tag == TAG_REDUNDTYPE
else 'blocklimit' if tag == TAG_BLOCKLIMIT
else 'disklimit' if tag == TAG_DISKLIMIT
else 'mleaflimit' if tag == TAG_MLEAFLIMIT
else 'sizelimit' if tag == TAG_SIZELIMIT
else 'namelimit' if tag == TAG_NAMELIMIT
else 'utaglimit' if tag == TAG_UTAGLIMIT
else 'uattrlimit' if tag == TAG_UATTRLIMIT
else 'config 0x%02x' % (tag & 0xff),
' w%d' % w if w else '',
size)
elif (tag & 0xff00) == TAG_GSTATE:
return '%s%s %d' % (
'grm' if tag == TAG_GRM
else 'gstate 0x%02x' % (tag & 0xff),
' w%d' % w if w else '',
size)
elif (tag & 0xff00) == TAG_NAME:
return '%s%s %d' % (
'branch' if tag == TAG_BRANCH
else 'bookmark' if tag == TAG_BOOKMARK
else 'reg' if tag == TAG_REG
else 'dir' if tag == TAG_DIR
else 'name 0x%02x' % (tag & 0xff),
' w%d' % w if w else '',
size)
elif (tag & 0xff00) == TAG_STRUCT:
return '%s%s %d' % (
'inlined' if tag == TAG_INLINED
else 'block' if tag == TAG_BLOCK
else 'btree' if tag == TAG_BTREE
else 'mdir' if tag == TAG_MDIR
else 'mtree' if tag == TAG_MTREE
else 'mroot' if tag == TAG_MROOT
else 'did' if tag == TAG_DID
else 'struct 0x%02x' % (tag & 0xff),
' w%d' % w if w else '',
size)
elif (tag & 0xff00) == TAG_UATTR:
return 'uattr 0x%02x%s %d' % (
tag & 0xff,
' w%d' % w if w else '',
size)
elif (tag & 0xff00) == TAG_SATTR:
return 'sattr 0x%02x%s %d' % (
tag & 0xff,
' w%d' % w if w else '',
size)
elif (tag & 0xff00) == TAG_CKSUM:
return 'cksum%x%s %d' % (
1 if tag & 0x1 else 0,
' 0x%x' % w if w > 0 else '',
size)
elif tag == TAG_ECKSUM:
return 'ecksum%s %d' % (
' 0x%x' % w if w > 0 else '',
size)
elif tag & 0x4000:
return 'alt%s%s 0x%x w%d %s' % (
'r' if tag & 0x1000 else 'b',
'gt' if tag & 0x2000 else 'le',
tag & 0x0fff,
w,
'0x%x' % (0xffffffff & (off-size))
if off is not None
else '-%d' % off)
else:
return '0x%04x w%d %d' % (tag, w, size)
# this type is used for tree representations
TBranch = co.namedtuple('TBranch', 'a, b, d, c')
# our core rbyd type
class Rbyd:
def __init__(self, block, data, rev, off, trunk, weight):
self.block = block
self.data = data
self.rev = rev
self.off = off
self.trunk = trunk
self.weight = weight
self.redund_blocks = []
def addr(self):
if not self.redund_blocks:
return '0x%x.%x' % (self.block, self.trunk)
else:
return '0x{%x,%s}.%x' % (
self.block,
','.join('%x' % block for block in self.redund_blocks),
self.trunk)
@classmethod
def fetch(cls, f, block_size, blocks, trunk=None):
if isinstance(blocks, int):
blocks = [blocks]
if len(blocks) > 1:
# fetch all blocks
rbyds = [cls.fetch(f, block_size, block, trunk) for block in blocks]
# determine most recent revision
i = 0
for i_, rbyd in enumerate(rbyds):
# compare with sequence arithmetic
if rbyd and (
not rbyds[i]
or not ((rbyd.rev - rbyds[i].rev) & 0x80000000)
or (rbyd.rev == rbyds[i].rev
and rbyd.trunk > rbyds[i].trunk)):
i = i_
# keep track of the other blocks
rbyd = rbyds[i]
rbyd.redund_blocks = [rbyds[(i+1+j) % len(rbyds)].block
for j in range(len(rbyds)-1)]
return rbyd
else:
# block may encode a trunk
block = blocks[0]
if isinstance(block, tuple):
if trunk is None:
trunk = block[1]
block = block[0]
# seek to the block
f.seek(block * block_size)
data = f.read(block_size)
# fetch the rbyd
rev = fromle32(data[0:4])
cksum = 0
cksum_ = crc32c(data[0:4])
off = 0
j_ = 4
trunk_ = 0
trunk__ = 0
weight = 0
weight_ = 0
weight__ = 0
wastrunk = False
trunkoff = None
while j_ < len(data) and (not trunk or off <= trunk):
v, tag, w, size, d = fromtag(data[j_:])
if v != (popc(cksum_) & 1):
break
cksum_ = crc32c(data[j_:j_+d], cksum_)
j_ += d
if not tag & 0x4000 and j_ + size > len(data):
break
# take care of cksums
if not tag & 0x4000:
if (tag & 0xff00) != TAG_CKSUM:
cksum_ = crc32c(data[j_:j_+size], cksum_)
# found a cksum?
else:
cksum__ = fromle32(data[j_:j_+4])
if cksum_ != cksum__:
break
# commit what we have
off = trunkoff if trunkoff else j_ + size
cksum = cksum_
trunk_ = trunk__
weight = weight_
# evaluate trunks
if (tag & 0xe000) != 0x2000 and (
not trunk or trunk >= j_-d or wastrunk):
# new trunk?
if not wastrunk:
wastrunk = True
trunk__ = j_-d
weight__ = 0
# keep track of weight
weight__ += w
# end of trunk?
if not tag & 0x4000:
wastrunk = False
# update weight
weight_ = weight__
# keep track of off for best matching trunk
if trunk and j_ + size > trunk:
trunkoff = j_ + size
if not tag & 0x4000:
j_ += size
return cls(block, data, rev, off, trunk_, weight)
def lookup(self, rid, tag):
if not self:
return True, 0, -1, 0, 0, 0, b'', []
lower = -1
upper = self.weight
path = []
# descend down tree
j = self.trunk
while True:
_, alt, weight_, jump, d = fromtag(self.data[j:])
# found an alt?
if alt & 0x4000:
# follow?
if ((rid, tag & 0xfff) > (upper-weight_-1, alt & 0xfff)
if alt & 0x2000
else ((rid, tag & 0xfff)
<= (lower+weight_, alt & 0xfff))):
lower += upper-lower-1-weight_ if alt & 0x2000 else 0
upper -= upper-lower-1-weight_ if not alt & 0x2000 else 0
j = j - jump
# figure out which color
if alt & 0x1000:
_, nalt, _, _, _ = fromtag(self.data[j+jump+d:])
if nalt & 0x1000:
path.append((j+jump, j, True, 'y'))
else:
path.append((j+jump, j, True, 'r'))
else:
path.append((j+jump, j, True, 'b'))
# stay on path
else:
lower += weight_ if not alt & 0x2000 else 0
upper -= weight_ if alt & 0x2000 else 0
j = j + d
# figure out which color
if alt & 0x1000:
_, nalt, _, _, _ = fromtag(self.data[j:])
if nalt & 0x1000:
path.append((j-d, j, False, 'y'))
else:
path.append((j-d, j, False, 'r'))
else:
path.append((j-d, j, False, 'b'))
# found tag
else:
rid_ = upper-1
tag_ = alt
w_ = rid_-lower
done = not tag_ or (rid_, tag_) < (rid, tag)
return done, rid_, tag_, w_, j, d, self.data[j+d:j+d+jump], path
def __bool__(self):
return bool(self.trunk)
def __eq__(self, other):
return self.block == other.block and self.trunk == other.trunk
def __ne__(self, other):
return not self.__eq__(other)
def __iter__(self):
tag = 0
rid = -1
while True:
done, rid, tag, w, j, d, data, _ = self.lookup(rid, tag+0x1)
if done:
break
yield rid, tag, w, j, d, data
# create tree representation for debugging
def tree(self):
trunks = co.defaultdict(lambda: (-1, 0))
alts = co.defaultdict(lambda: {})
rid, tag = -1, 0
while True:
done, rid, tag, w, j, d, data, path = self.lookup(rid, tag+0x1)
# found end of tree?
if done:
break
# keep track of trunks/alts
trunks[j] = (rid, tag)
for j_, j__, followed, c in path:
if followed:
alts[j_] |= {'f': j__, 'c': c}
else:
alts[j_] |= {'nf': j__, 'c': c}
# prune any alts with unreachable edges
pruned = {}
for j_, alt in alts.items():
if 'f' not in alt:
pruned[j_] = alt['nf']
elif 'nf' not in alt:
pruned[j_] = alt['f']
for j_ in pruned.keys():
del alts[j_]
for j_, alt in alts.items():
while alt['f'] in pruned:
alt['f'] = pruned[alt['f']]
while alt['nf'] in pruned:
alt['nf'] = pruned[alt['nf']]
# find the trunk and depth of each alt, assuming pruned alts
# didn't exist
def rec_trunk(j_):
if j_ not in alts:
return trunks[j_]
else:
if 'nft' not in alts[j_]:
alts[j_]['nft'] = rec_trunk(alts[j_]['nf'])
return alts[j_]['nft']
for j_ in alts.keys():
rec_trunk(j_)
for j_, alt in alts.items():
if alt['f'] in alts:
alt['ft'] = alts[alt['f']]['nft']
else:
alt['ft'] = trunks[alt['f']]
def rec_height(j_):
if j_ not in alts:
return 0
else:
if 'h' not in alts[j_]:
alts[j_]['h'] = max(
rec_height(alts[j_]['f']),
rec_height(alts[j_]['nf'])) + 1
return alts[j_]['h']
for j_ in alts.keys():
rec_height(j_)
t_depth = max((alt['h']+1 for alt in alts.values()), default=0)
# convert to more general tree representation
tree = set()
for j, alt in alts.items():
# note all non-trunk edges should be black
tree.add(TBranch(
a=alt['nft'],
b=alt['nft'],
d=t_depth-1 - alt['h'],
c=alt['c'],
))
tree.add(TBranch(
a=alt['nft'],
b=alt['ft'],
d=t_depth-1 - alt['h'],
c='b',
))
return tree, t_depth
# btree lookup with this rbyd as the root
def btree_lookup(self, f, block_size, bid, *,
depth=None):
rbyd = self
rid = bid
depth_ = 1
path = []
# corrupted? return a corrupted block once
if not rbyd:
return bid > 0, bid, 0, rbyd, -1, [], path
while True:
# collect all tags, normally you don't need to do this
# but we are debugging here
name = None
tags = []
branch = None
rid_ = rid
tag = 0
w = 0
for i in it.count():
done, rid__, tag, w_, j, d, data, _ = rbyd.lookup(
rid_, tag+0x1)
if done or (i != 0 and rid__ != rid_):
break
# first tag indicates the branch's weight
if i == 0:
rid_, w = rid__, w_
# catch any branches
if tag == TAG_BTREE:
branch = (tag, j, d, data)
tags.append((tag, j, d, data))
# keep track of path
path.append((bid + (rid_-rid), w, rbyd, rid_, tags))
# descend down branch?
if branch is not None and (
not depth or depth_ < depth):
tag, j, d, data = branch
block, trunk, _, cksum = frombtree(data)
rbyd = Rbyd.fetch(f, block_size, block, trunk)
# corrupted? bail here so we can keep traversing the tree
if not rbyd:
return False, bid + (rid_-rid), w, rbyd, -1, [], path
rid -= (rid_-(w-1))
depth_ += 1
else:
return not tags, bid + (rid_-rid), w, rbyd, rid_, tags, path
# btree rbyd-tree generation for debugging
def btree_tree(self, f, block_size, *,
depth=None,
inner=False):
# find the max depth of each layer to nicely align trees
bdepths = {}
bid = -1
while True:
done, bid, w, rbyd, rid, tags, path = self.btree_lookup(
f, block_size, bid+1, depth=depth)
if done:
break
for d, (bid, w, rbyd, rid, tags) in enumerate(path):
_, rdepth = rbyd.tree()
bdepths[d] = max(bdepths.get(d, 0), rdepth)
# find all branches
tree = set()
root = None
branches = {}
bid = -1
while True:
done, bid, w, rbyd, rid, tags, path = self.btree_lookup(
f, block_size, bid+1, depth=depth)
if done:
break
d_ = 0
leaf = None
for d, (bid, w, rbyd, rid, tags) in enumerate(path):
if not tags:
continue
# map rbyd tree into B-tree space
rtree, rdepth = rbyd.tree()
# note we adjust our bid/rids to be left-leaning,
# this allows a global order and make tree rendering quite
# a bit easier
rtree_ = set()
for branch in rtree:
a_rid, a_tag = branch.a
b_rid, b_tag = branch.b
_, _, _, a_w, _, _, _, _ = rbyd.lookup(a_rid, 0)
_, _, _, b_w, _, _, _, _ = rbyd.lookup(b_rid, 0)
rtree_.add(TBranch(
a=(a_rid-(a_w-1), a_tag),
b=(b_rid-(b_w-1), b_tag),
d=branch.d,
c=branch.c,
))
rtree = rtree_
# connect our branch to the rbyd's root
if leaf is not None:
root = min(rtree,
key=lambda branch: branch.d,
default=None)
if root is not None:
r_rid, r_tag = root.a
else:
r_rid, r_tag = rid-(w-1), tags[0][0]
tree.add(TBranch(
a=leaf,
b=(bid-rid+r_rid, d, r_rid, r_tag),
d=d_-1,
c='b',
))
for branch in rtree:
# map rbyd branches into our btree space
a_rid, a_tag = branch.a
b_rid, b_tag = branch.b
tree.add(TBranch(
a=(bid-rid+a_rid, d, a_rid, a_tag),
b=(bid-rid+b_rid, d, b_rid, b_tag),
d=branch.d + d_ + bdepths.get(d, 0)-rdepth,
c=branch.c,
))
d_ += max(bdepths.get(d, 0), 1)
leaf = (bid-(w-1), d, rid-(w-1), TAG_BTREE)
# remap branches to leaves if we aren't showing inner branches
if not inner:
# step through each layer backwards
b_depth = max((branch.a[1]+1 for branch in tree), default=0)
# keep track of the original bids, unfortunately because we
# store the bids in the branches we overwrite these
tree = {(branch.b[0] - branch.b[2], branch) for branch in tree}
for bd in reversed(range(b_depth-1)):
# find leaf-roots at this level
roots = {}
for bid, branch in tree:
# choose the highest node as the root
if (branch.b[1] == b_depth-1
and (bid not in roots
or branch.d < roots[bid].d)):
roots[bid] = branch
# remap branches to leaf-roots
tree_ = set()
for bid, branch in tree:
if branch.a[1] == bd and branch.a[0] in roots:
branch = TBranch(
a=roots[branch.a[0]].b,
b=branch.b,
d=branch.d,
c=branch.c,
)
if branch.b[1] == bd and branch.b[0] in roots:
branch = TBranch(
a=branch.a,
b=roots[branch.b[0]].b,
d=branch.d,
c=branch.c,
)
tree_.add((bid, branch))
tree = tree_
# strip out bids
tree = {branch for _, branch in tree}
return tree, max((branch.d+1 for branch in tree), default=0)
# btree B-tree generation for debugging
def btree_btree(self, f, block_size, *,
depth=None,
inner=False):
# find all branches
tree = set()
root = None
branches = {}
bid = -1
while True:
done, bid, w, rbyd, rid, tags, path = self.btree_lookup(
f, block_size, bid+1, depth=depth)
if done:
break
# if we're not showing inner nodes, prefer names higher in
# the tree since this avoids showing vestigial names
name = None
if not inner:
name = None
for bid_, w_, rbyd_, rid_, tags_ in reversed(path):
for tag_, j_, d_, data_ in tags_:
if tag_ & 0x7f00 == TAG_NAME:
name = (tag_, j_, d_, data_)
if rid_-(w_-1) != 0:
break
a = root
for d, (bid, w, rbyd, rid, tags) in enumerate(path):
if not tags:
continue
b = (bid-(w-1), d, rid-(w-1),
(name if name else tags[0])[0])
# remap branches to leaves if we aren't showing
# inner branches
if not inner:
if b not in branches:
bid, w, rbyd, rid, tags = path[-1]
if not tags:
continue
branches[b] = (
bid-(w-1), len(path)-1, rid-(w-1),
(name if name else tags[0])[0])
b = branches[b]
# found entry point?
if root is None:
root = b
a = root
tree.add(TBranch(
a=a,
b=b,
d=d,
c='b',
))
a = b
return tree, max((branch.d+1 for branch in tree), default=0)
def main(disk, mroots=None, *,
block_size=None,
mleaf_weight=None,
color='auto',
**args):
# figure out what color should be
if color == 'auto':
color = sys.stdout.isatty()
elif color == 'always':
color = True
else:
color = False
# flatten mroots, default to 0x{0,1}
if not mroots:
mroots = [[0,1]]
mroots = [block for mroots_ in mroots for block in mroots_]
# we seek around a bunch, so just keep the disk open
with open(disk, 'rb') as f:
# if block_size is omitted, assume the block device is one big block
if block_size is None:
f.seek(0, os.SEEK_END)
block_size = f.tell()
# determine the mleaf_weight from the block_size, this is just for
# printing purposes
if mleaf_weight is None:
mleaf_weight = 1 << m.ceil(m.log2(block_size // 16))
# before we print, we need to do a pass for a few things:
# - find the actual mroot
# - find the total weight
bweight = 0
rweight = 0
mroot = Rbyd.fetch(f, block_size, mroots)
mdepth = 1
while True:
# corrupted?
if not mroot:
break
rweight = max(rweight, mroot.weight)
# stop here?
if args.get('depth') and mdepth >= args.get('depth'):
break
# fetch the next mroot
done, rid, tag, w, j, d, data, _ = mroot.lookup(-1, TAG_MROOT)
if not (not done and rid == -1 and tag == TAG_MROOT):
break
blocks = frommdir(data)
mroot = Rbyd.fetch(f, block_size, blocks)
mdepth += 1
# fetch the mdir, if there is one
mdir = None
if not args.get('depth') or mdepth < args.get('depth'):
done, rid, tag, w, j, _, data, _ = mroot.lookup(-1, TAG_MDIR)
if not done and rid == -1 and tag == TAG_MDIR:
blocks = frommdir(data)
mdir = Rbyd.fetch(f, block_size, blocks)
# corrupted?
if mdir:
rweight = max(rweight, mdir.weight)
# fetch the actual mtree, if there is one
mtree = None
if not args.get('depth') or mdepth < args.get('depth'):
done, rid, tag, w, j, d, data, _ = mroot.lookup(-1, TAG_MTREE)
if not done and rid == -1 and tag == TAG_MTREE:
block, trunk, w, cksum = frombtree(data)
mtree = Rbyd.fetch(f, block_size, block, trunk)
bweight = w
# traverse entries
mbid = -1
while True:
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
f, block_size, mbid+1,
depth=args.get('depth', mdepth)-mdepth)
if done:
break
# corrupted?
if not rbyd:
continue
mdir__ = None
if (not args.get('depth')
or mdepth+len(path) < args.get('depth')):
mdir__ = next(((tag, j, d, data)
for tag, j, d, data in tags
if tag == TAG_MDIR),
None)
if mdir__:
# fetch the mdir
_, _, _, data = mdir__
blocks = frommdir(data)
mdir_ = Rbyd.fetch(f, block_size, blocks)
# corrupted?
if mdir_:
rweight = max(rweight, mdir_.weight)
# precompute rbyd-tree if requested
t_width = 0
if args.get('tree'):
# compute mroot chain "tree", prefix our actual mtree with this
tree = set()
d_ = 0
mroot_ = Rbyd.fetch(f, block_size, mroots)
mdepth_ = 1
for d in it.count():
# corrupted?
if not mroot_:
break
# compute the mroots rbyd-tree
rtree, rdepth = mroot_.tree()
# connect branch to our root
if d > 0:
root = min(rtree,
key=lambda branch: branch.d,
default=None)
if root:
r_rid, r_tag = root.a
else:
_, r_rid, r_tag, _, _, _, _, _ = mroot_.lookup(-1, 0x1)
tree.add(TBranch(
a=(-1, d-1, 0, -1, TAG_MROOT),
b=(-1, d, 0, r_rid, r_tag),
d=d_-1,
c='b',
))
# map the tree into our metadata space
for branch in rtree:
a_rid, a_tag = branch.a
b_rid, b_tag = branch.b
tree.add(TBranch(
a=(-1, d, 0, a_rid, a_tag),
b=(-1, d, 0, b_rid, b_tag),
d=d_ + branch.d,
c=branch.c,
))
d_ += rdepth
# stop here?
if args.get('depth') and mdepth_ >= args.get('depth'):
break
# fetch the next mroot
done, rid, tag, w, j, _, data, _ = mroot_.lookup(-1, TAG_MROOT)
if not (not done and rid == -1 and tag == TAG_MROOT):
break
blocks = frommdir(data)
mroot_ = Rbyd.fetch(f, block_size, blocks)
mdepth_ += 1
# compute mdir's rbyd-tree if there is one
if mdir:
rtree, rdepth = mdir.tree()
# connect branch to our root
root = min(rtree,
key=lambda branch: branch.d,
default=None)
if root:
r_rid, r_tag = root.a
else:
_, r_rid, r_tag, _, _, _, _, _ = mdir.lookup(-1, 0x1)
tree.add(TBranch(
a=(-1, d, 0, -1, TAG_MDIR),
b=(0, 0, 0, r_rid, r_tag),
d=d_-1,
c='b',
))
# map the tree into our metadata space
for branch in rtree:
a_rid, a_tag = branch.a
b_rid, b_tag = branch.b
tree.add(TBranch(
a=(0, 0, 0, a_rid, a_tag),
b=(0, 0, 0, b_rid, b_tag),
d=d_ + branch.d,
c=branch.c,
))
# compute the mtree's rbyd-tree if there is one
if mtree:
tree_, tdepth = mtree.btree_tree(
f, block_size,
depth=args.get('depth', mdepth)-mdepth,
inner=args.get('inner'))
# connect a branch to the root of the tree
root = min(tree_, key=lambda branch: branch.d, default=None)
if root:
r_bid, r_bd, r_rid, r_tag = root.a
tree.add(TBranch(
a=(-1, d, 0, -1, TAG_MTREE),
b=(r_bid, r_bd, r_rid, 0, r_tag),
d=d_-1,
c='b',
))
# map the tree into our metadata space
for branch in tree_:
a_bid, a_bd, a_rid, a_tag = branch.a
b_bid, b_bd, b_rid, b_tag = branch.b
tree.add(TBranch(
a=(a_bid, a_bd, a_rid, 0, a_tag),
b=(b_bid, b_bd, b_rid, 0, b_tag),
d=d_ + branch.d,
c=branch.c,
))
# find the max depth of each mdir to nicely align trees
mdepth_ = 0
mbid = -1
while True:
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
f, block_size, mbid+1,
depth=args.get('depth', mdepth)-mdepth)
if done:
break
# corrupted?
if not rbyd:
continue
mdir__ = None
if (not args.get('depth')
or mdepth+len(path) < args.get('depth')):
mdir__ = next(((tag, j, d, data)
for tag, j, d, data in tags
if tag == TAG_MDIR),
None)
if mdir__:
# fetch the mdir
_, _, _, data = mdir__
blocks = frommdir(data)
mdir_ = Rbyd.fetch(f, block_size, blocks)
rtree, rdepth = mdir_.tree()
mdepth_ = max(mdepth_, rdepth)
# compute the rbyd-tree for each mdir
mbid = -1
while True:
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
f, block_size, mbid+1,
depth=args.get('depth', mdepth)-mdepth)
if done:
break
# corrupted?
if not rbyd:
continue
mdir__ = None
if (not args.get('depth')
or mdepth+len(path) < args.get('depth')):
mdir__ = next(((tag, j, d, data)
for tag, j, d, data in tags
if tag == TAG_MDIR),
None)
if mdir__:
# fetch the mdir
_, _, _, data = mdir__
blocks = frommdir(data)
mdir_ = Rbyd.fetch(f, block_size, blocks)
rtree, rdepth = mdir_.tree()
# connect the root to the mtree
branch = max(
(branch for branch in tree
if branch.b[0] == mbid-(mw-1)),
key=lambda branch: branch.d,
default=None)
if branch:
root = min(rtree,
key=lambda branch: branch.d,
default=None)
if root:
r_rid, r_tag = root.a
else:
_, r_rid, r_tag, _, _, _, _, _ = (
mdir_.lookup(-1, 0x1))
tree.add(TBranch(
a=branch.b,
b=(mbid-(mw-1), len(path), 0, r_rid, r_tag),
d=d_ + tdepth,
c='b',
))
# map the tree into our metadata space
for branch in rtree:
a_rid, a_tag = branch.a
b_rid, b_tag = branch.b
tree.add(TBranch(
a=(mbid-(mw-1), len(path), 0, a_rid, a_tag),
b=(mbid-(mw-1), len(path), 0, b_rid, b_tag),
d=(d_ + tdepth + 1
+ branch.d + mdepth_-rdepth),
c=branch.c,
))
# remap branches to leaves if we aren't showing inner branches
if not args.get('inner'):
# step through each layer backwards
b_depth = max((branch.b[1]+1 for branch in tree), default=0)
# keep track of the original bids, unfortunately because we
# store the bids in the branches we overwrite these
tree = {(branch.b[0] - branch.b[2], branch)
for branch in tree}
for bd in reversed(range(b_depth-1)):
# find leaf-roots at this level
roots = {}
for bid, branch in tree:
# choose the highest node as the root
if (branch.b[1] == b_depth-1
and (bid not in roots
or branch.d < roots[bid].d)):
roots[bid] = branch
# remap branches to leaf-roots
tree_ = set()
for bid, branch in tree:
# note we ignore mroot branches, we don't collapse
# normally these
if (branch.a[0] != -1
and branch.a[1] == bd
and branch.a[0] in roots):
branch = TBranch(
a=roots[branch.a[0]].b,
b=branch.b,
d=branch.d,
c=branch.c,
)
if (branch.b[0] != -1
and branch.b[1] == bd
and branch.b[0] in roots):
branch = TBranch(
a=branch.a,
b=roots[branch.b[0]].b,
d=branch.d,
c=branch.c,
)
tree_.add((bid, branch))
tree = tree_
# strip out bids
tree = {branch for _, branch in tree}
# precompute B-tree if requested
elif args.get('btree'):
# compute mroot chain "tree", prefix our actual mtree with this
tree = set()
mroot_ = Rbyd.fetch(f, block_size, mroots)
mdepth_ = 1
for d in it.count():
# corrupted?
if not mroot_:
break
# connect branch to our first tag
if d > 0:
done, rid, tag, w, j, _, data, _ = mroot_.lookup(-1, 0x1)
if not done:
tree.add(TBranch(
a=(-1, d-1, 0, -1, TAG_MROOT),
b=(-1, d, 0, rid, tag),
d=0,
c='b',
))
# stop here?
if args.get('depth') and mdepth_ >= args.get('depth'):
break
# fetch the next mroot
done, rid, tag, w, j, _, data, _ = mroot_.lookup(-1, TAG_MROOT)
if not (not done and rid == -1 and tag == TAG_MROOT):
break
blocks = frommdir(data)
mroot_ = Rbyd.fetch(f, block_size, blocks)
mdepth_ += 1
# create a branch to our mdir if there is one
if mdir:
# connect branch to our first tag
done, rid, tag, w, j, _, data, _ = mdir.lookup(-1, 0x1)
if not done:
tree.add(TBranch(
a=(-1, d, 0, -1, TAG_MDIR),
b=(0, 0, 0, rid, tag),
d=0,
c='b',
))
# compute the mtree's B-tree if there is one
if mtree:
tree_, tdepth = mtree.btree_btree(
f, block_size,
depth=args.get('depth', mdepth)-mdepth,
inner=args.get('inner'))
# connect a branch to the root of the tree
root = min(tree_, key=lambda branch: branch.d, default=None)
if root:
r_bid, r_bd, r_rid, r_tag = root.a
tree.add(TBranch(
a=(-1, d, 0, -1, TAG_MTREE),
b=(r_bid, r_bd, r_rid, 0, r_tag),
d=0,
c='b',
))
# map the tree into our metadata space
for branch in tree_:
a_bid, a_bd, a_rid, a_tag = branch.a
b_bid, b_bd, b_rid, b_tag = branch.b
tree.add(TBranch(
a=(a_bid, a_bd, a_rid, 0, a_tag),
b=(b_bid, b_bd, b_rid, 0, b_tag),
d=1 + branch.d,
c=branch.c,
))
# remap branches to leaves if we aren't showing inner branches
if not args.get('inner'):
mbid = -1
while True:
done, mbid, mw, rbyd, rid, tags, path = (
mtree.btree_lookup(
f, block_size, mbid+1,
depth=args.get('depth', mdepth)-mdepth))
if done:
break
# corrupted?
if not rbyd:
continue
mdir__ = None
if (not args.get('depth')
or mdepth+len(path) < args.get('depth')):
mdir__ = next(((tag, j, d, data)
for tag, j, d, data in tags
if tag == TAG_MDIR),
None)
if mdir__:
# fetch the mdir
_, _, _, data = mdir__
blocks = frommdir(data)
mdir_ = Rbyd.fetch(f, block_size, blocks)
# find the first entry in the mdir, map branches
# to this entry
done, rid, tag, _, j, d, data, _ = (
mdir_.lookup(-1, 0x1))
tree_ = set()
for branch in tree:
if branch.a[0] == mbid-(mw-1):
a_bid, a_bd, _, _, _ = branch.a
branch = TBranch(
a=(a_bid, a_bd+1, 0, rid, tag),
b=branch.b,
d=branch.d,
c=branch.c,
)
if branch.b[0] == mbid-(mw-1):
b_bid, b_bd, _, _, _ = branch.b
branch = TBranch(
a=branch.a,
b=(b_bid, b_bd+1, 0, rid, tag),
d=branch.d,
c=branch.c,
)
tree_.add(branch)
tree = tree_
# common tree renderer
if args.get('tree') or args.get('btree'):
# find the max depth from the tree
t_depth = max((branch.d+1 for branch in tree), default=0)
if t_depth > 0:
t_width = 2*t_depth + 2
def treerepr(mbid, mw, md, mrid, rid, tag):
if t_depth == 0:
return ''
def branchrepr(x, d, was):
for branch in tree:
if branch.d == d and branch.b == x:
if any(branch.d == d and branch.a == x
for branch in tree):
return '+-', branch.c, branch.c
elif any(branch.d == d
and x > min(branch.a, branch.b)
and x < max(branch.a, branch.b)
for branch in tree):
return '|-', branch.c, branch.c
elif branch.a < branch.b:
return '\'-', branch.c, branch.c
else:
return '.-', branch.c, branch.c
for branch in tree:
if branch.d == d and branch.a == x:
return '+ ', branch.c, None
for branch in tree:
if (branch.d == d
and x > min(branch.a, branch.b)
and x < max(branch.a, branch.b)):
return '| ', branch.c, was
if was:
return '--', was, was
return ' ', None, None
trunk = []
was = None
for d in range(t_depth):
t, c, was = branchrepr(
(mbid-max(mw-1, 0), md, mrid-max(mw-1, 0), rid, tag),
d, was)
trunk.append('%s%s%s%s' % (
'\x1b[33m' if color and c == 'y'
else '\x1b[31m' if color and c == 'r'
else '\x1b[90m' if color and c == 'b'
else '',
t,
('>' if was else ' ') if d == t_depth-1 else '',
'\x1b[m' if color and c else ''))
return '%s ' % ''.join(trunk)
def dbg_mdir(mdir, mbid, mw, md):
for i, (rid, tag, w, j, d, data) in enumerate(mdir):
# show human-readable tag representation
print('%12s %s%-57s' % (
'{%s}:' % ','.join('%04x' % block
for block in it.chain([mdir.block],
mdir.redund_blocks))
if i == 0 else '',
treerepr(mbid-max(mw-1, 0), 0, md, 0, rid, tag)
if args.get('tree') or args.get('btree') else '',
'%*s %-22s%s' % (
w_width, '%d.%d-%d' % (
mbid//mleaf_weight, rid-(w-1), rid)
if w > 1 else '%d.%d' % (mbid//mleaf_weight, rid)
if w > 0 or i == 0 else '',
tagrepr(tag, w, len(data), j),
' %s' % next(xxd(data, 8), '')
if not args.get('no_truncate') else '')))
# show in-device representation
if args.get('device'):
print('%11s %*s%*s %s' % (
'',
t_width, '',
w_width, '',
'%-22s%s' % (
'%04x %08x %07x' % (tag, w, len(data)),
' %s' % ' '.join(
'%08x' % fromle32(
mdir.data[j+d+i*4
: j+d+min(i*4+4,len(data))])
for i in range(
min(m.ceil(len(data)/4),
3)))[:23]
if not args.get('no_truncate')
and not tag & 0x4000 else '')))
# show on-disk encoding of tags
if args.get('raw'):
for o, line in enumerate(xxd(mdir.data[j:j+d])):
print('%11s: %*s%*s %s' % (
'%04x' % (j + o*16),
t_width, '',
w_width, '',
line))
if args.get('raw') or args.get('no_truncate'):
if not tag & 0x4000:
for o, line in enumerate(xxd(data)):
print('%11s: %*s%*s %s' % (
'%04x' % (j+d + o*16),
t_width, '',
w_width, '',
line))
# prbyd here means the last rendered rbyd, we update
# in dbg_branch to always print interleaved addresses
prbyd = None
def dbg_branch(bid, w, rbyd, rid, tags, bd):
nonlocal prbyd
# show human-readable representation
for i, (tag, j, d, data) in enumerate(tags):
print('%12s %s%*s %-22s %s' % (
'%04x.%04x:' % (rbyd.block, rbyd.trunk)
if prbyd is None or rbyd != prbyd
else '',
treerepr(bid, w, bd, rid, 0, tag)
if args.get('tree') or args.get('btree') else '',
w_width, '' if i != 0
else '%d-%d' % (
(bid-(w-1))//mleaf_weight,
bid//mleaf_weight)
if (w//mleaf_weight) > 1
else bid//mleaf_weight if w > 0
else '',
tagrepr(tag, w if i == 0 else 0, len(data), None),
# note we render names a bit different here
next(xxd(data, 8), '') if not args.get('no_truncate')
else ''))
prbyd = rbyd
# show in-device representation
if args.get('device'):
print('%11s %*s%*s %-22s%s' % (
'',
t_width, '',
w_width, '',
'%04x %08x %07x' % (tag, w if i == 0 else 0, len(data)),
' %s' % ' '.join(
'%08x' % fromle32(
rbyd.data[j+d+i*4 : j+d + min(i*4+4,len(data))])
for i in range(min(m.ceil(len(data)/4), 3)))[:23]))
# show on-disk encoding of tags/data
if args.get('raw'):
for o, line in enumerate(xxd(rbyd.data[j:j+d])):
print('%11s: %*s%*s %s' % (
'%04x' % (j + o*16),
t_width, '',
w_width, '',
line))
if args.get('raw') or args.get('no_truncate'):
for o, line in enumerate(xxd(data)):
print('%11s: %*s%*s %s' % (
'%04x' % (j+d + o*16),
t_width, '',
w_width, '',
line))
#### actual debugging begins here
# print some information about the mtree
print('mtree %s, rev %d, weight %d.%d' % (
mroot.addr(), mroot.rev, bweight//mleaf_weight, 1*mleaf_weight))
# print header
w_width = (m.ceil(m.log10(max(1, bweight//mleaf_weight)+1))
+ 2*m.ceil(m.log10(max(1, rweight)+1))
+ 2)
print('%-11s %*s%-*s %-22s %s' % (
'mdir',
t_width, '',
w_width, 'mid',
'tag',
'data (truncated)'
if not args.get('no_truncate') else ''))
# show each mroot
prbyd = None
ppath = []
corrupted = False
mroot = Rbyd.fetch(f, block_size, mroots)
mdepth = 1
for d in it.count():
# corrupted?
if not mroot:
print('{%s}: %s%s%s' % (
','.join('%04x' % block
for block in it.chain([mroot.block],
mroot.redund_blocks)),
'\x1b[31m' if color else '',
'(corrupted mroot %s)' % mroot.addr(),
'\x1b[m' if color else ''))
corrupted = True
break
else:
# show the mdir
dbg_mdir(mroot, -1, 0, d)
# stop here?
if args.get('depth') and mdepth >= args.get('depth'):
break
# fetch the next mroot
done, rid, tag, w, j, _, data, _ = mroot.lookup(-1, TAG_MROOT)
if not (not done and rid == -1 and tag == TAG_MROOT):
break
blocks = frommdir(data)
mroot = Rbyd.fetch(f, block_size, blocks)
mdepth += 1
# show the mdir, if there is one
if not args.get('depth') or mdepth < args.get('depth'):
done, rid, tag, w, j, _, data, _ = mroot.lookup(-1, TAG_MDIR)
if not done and rid == -1 and tag == TAG_MDIR:
blocks = frommdir(data)
mdir = Rbyd.fetch(f, block_size, blocks)
# corrupted?
if not mdir:
print('{%s}: %s%s%s' % (
','.join('%04x' % block
for block in it.chain([mdir.block],
mdir.redund_blocks)),
'\x1b[31m' if color else '',
'(corrupted mdir %s)' % mdir.addr(),
'\x1b[m' if color else ''))
corrupted = True
else:
# show the mdir
dbg_mdir(mdir, 0, 0, 0)
# fetch the actual mtree, if there is one
if not args.get('depth') or mdepth < args.get('depth'):
done, rid, tag, w, j, d, data, _ = mroot.lookup(-1, TAG_MTREE)
if not done and rid == -1 and tag == TAG_MTREE:
block, trunk, w, cksum = frombtree(data)
mtree = Rbyd.fetch(f, block_size, block, trunk)
# traverse entries
mbid = -1
while True:
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
f, block_size, mbid+1,
depth=args.get('depth', mdepth)-mdepth)
if done:
break
# print inner btree entries if requested
if args.get('inner'):
changed = False
for (x, px) in it.zip_longest(
enumerate(path[:-1]),
enumerate(ppath[:-1])):
if x is None:
break
if not (changed or px is None or x != px):
continue
changed = True
# show the inner entry
d, (mid_, w_, rbyd_, rid_, tags_) = x
dbg_branch(mid_, w_, rbyd_, rid_, tags_, d)
ppath = path
# corrupted? try to keep printing the tree
if not rbyd:
print('%11s: %*s%s%s%s' % (
'%04x.%04x' % (rbyd.block, rbyd.trunk),
t_width, '',
'\x1b[31m' if color else '',
'(corrupted rbyd %s)' % rbyd.addr(),
'\x1b[m' if color else ''))
prbyd = rbyd
corrupted = True
continue
# if we're not showing inner nodes, prefer names higher in
# the tree since this avoids showing vestigial names
if not args.get('inner'):
name = None
for mid_, w_, rbyd_, rid_, tags_ in reversed(path):
for tag_, j_, d_, data_ in tags_:
if tag_ & 0x7f00 == TAG_NAME:
name = (tag_, j_, d_, data_)
if rid_-(w_-1) != 0:
break
if name is not None:
tags = [name] + [(tag, j, d, data)
for tag, j, d, data in tags
if tag & 0x7f00 != TAG_NAME]
# find mdir in the tags
mdir__ = None
if (not args.get('depth')
or mdepth+len(path) < args.get('depth')):
mdir__ = next(((tag, j, d, data)
for tag, j, d, data in tags
if tag == TAG_MDIR),
None)
# print btree entries in certain cases
if args.get('inner') or not mdir__:
dbg_branch(mbid, mw, rbyd, rid, tags, len(path)-1)
if not mdir__:
continue
# fetch the mdir
_, _, _, data = mdir__
blocks = frommdir(data)
mdir_ = Rbyd.fetch(f, block_size, blocks)
# corrupted?
if not mdir_:
print('{%s}: %*s%s%s%s' % (
','.join('%04x' % block
for block in it.chain([mdir_.block],
mdir_.redund_blocks)),
t_width, '',
'\x1b[31m' if color else '',
'(corrupted mdir %s)' % mdir_.addr(),
'\x1b[m' if color else ''))
corrupted = True
else:
# show the mdir
dbg_mdir(mdir_, mbid, mw, len(path))
# force next btree entry to be shown
prbyd = None
if args.get('error_on_corrupt') and corrupted:
sys.exit(2)
if __name__ == "__main__":
import argparse
import sys
parser = argparse.ArgumentParser(
description="Debug littlefs's metadata tree.",
allow_abbrev=False)
parser.add_argument(
'disk',
help="File containing the block device.")
parser.add_argument(
'mroots',
nargs='*',
type=rbydaddr,
help="Block address of the mroots. Defaults to 0x{0,1}.")
parser.add_argument(
'-B', '--block-size',
type=lambda x: int(x, 0),
help="Block size in bytes.")
parser.add_argument(
'-M', '--mleaf-weight',
type=lambda x: int(x, 0),
help="Maximum weight of mdirs for mid decoding. Defaults to a "
"block_size derived value.")
parser.add_argument(
'--color',
choices=['never', 'always', 'auto'],
default='auto',
help="When to use terminal colors. Defaults to 'auto'.")
parser.add_argument(
'-r', '--raw',
action='store_true',
help="Show the raw data including tag encodings.")
parser.add_argument(
'-x', '--device',
action='store_true',
help="Show the device-side representation of tags.")
parser.add_argument(
'-T', '--no-truncate',
action='store_true',
help="Don't truncate, show the full contents.")
parser.add_argument(
'-i', '--inner',
action='store_true',
help="Show inner branches.")
parser.add_argument(
'-t', '--tree',
action='store_true',
help="Show the underlying rbyd trees.")
parser.add_argument(
'-b', '--btree',
action='store_true',
help="Show the underlying B-tree.")
parser.add_argument(
'-Z', '--depth',
nargs='?',
type=lambda x: int(x, 0),
const=0,
help="Depth of tree to show.")
parser.add_argument(
'-e', '--error-on-corrupt',
action='store_true',
help="Error if B-tree is corrupt.")
sys.exit(main(**{k: v
for k, v in vars(parser.parse_intermixed_args()).items()
if v is not None}))