5502fe55ab
Ckfetches implements what might be your first idea on how to check
checksums in a filesystem: Check each block/mdir on first access
(fetch) to make sure the data is sound.
Unfortunately, there are two problems with this approach, both which
come from the fact that blocks are big and can't fit in RAM:
1. We still have a checksum-read hole.
We can't keep a whole block around in RAM, so reads after a fetch may
need to reread from disk, at which point new bit-errors may slip in
undetected.
This is especially problematic for traversing our rbyds, which
involves a lot of small reads in a block.
2. Ckfetches may have a surprisingly negative performance impact.
Consider the case of reading a large file with a bunch of small
reads. Because we don't cache blocks, each read may need a btree
lookup, and a full block fetch. On paper this can quickly end up
O(b^2), which is not great.
Though this is helped by the file buffer. It will be interesting to
benchmark and see if this theoretical O(b^2) translates to poor
performance in practice.
Note ckreads has this same performance issue.
Still, despite these problems, ckfetches may be useful for cases where
you just want an extra layer of safety, or don't care about the tiny
chance an error is introduced between a fetch an subsequent read.
---
Like ckprogs/ckreads, ckfetches is an opt-in feature, and requires both
1. defining LFS_CKFETCHES, and 2. passing LFS_M_CKFETCHES during mount.
This is a bit of a quick implementation to get testing in place, so the
code cost is probably higher than strictly necessary. If we can refactor
the code internally to avoid all the duplicate lfsr_rbyd_fetchck/
lfsr_bptr_ck calls, we can probably bring this down a bit:
code stack
before: 36428 2680
yes-ckfetches: 36848 (+1.2%) 2680 (+0.0%)
no-ckfetches: 36428 (+0.0%) 2680 (+0.0%)
Oh, and also added lfs_emubd_flipbit to allow tests to manually flip
bits themselves. LFS_EMUBD_BADBLOCK_PROGFLIP is quick to find the above
mentioned checksum-read hole.
This could be done manually with read+erase+prog, but no reason to make
it harder than it needs to be.
941 lines
30 KiB
TOML
941 lines
30 KiB
TOML
# Advanced mount tests
|
|
after = ['test_mtree', 'test_traversal']
|
|
|
|
|
|
# test we can mount
|
|
[cases.test_mount_simple]
|
|
code = '''
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
# test that various mount flags don't assert and are returned by
|
|
# lfsr_fs_stat
|
|
[cases.test_mount_flags]
|
|
defines.RDONLY = [false, true]
|
|
defines.CKPROGS = [false, true]
|
|
defines.CKREADS = [false, true]
|
|
defines.CKFETCHES = [false, true]
|
|
defines.FLUSH = [false, true]
|
|
defines.SYNC = [false, true]
|
|
defines.MTREEONLY = [false, true]
|
|
defines.MKCONSISTENT = [false, true]
|
|
defines.LOOKAHEAD = [false, true]
|
|
defines.COMPACT = [false, true]
|
|
defines.CKMETA = [false, true]
|
|
defines.CKDATA = [false, true]
|
|
if = [
|
|
'LFS_IFDEF_CKPROGS(true, !CKPROGS)',
|
|
'LFS_IFDEF_CKREADS(true, !CKREADS)',
|
|
'LFS_IFDEF_CKFETCHES(true, !CKFETCHES)',
|
|
'!RDONLY || !MKCONSISTENT',
|
|
'!RDONLY || !LOOKAHEAD',
|
|
'!RDONLY || !COMPACT',
|
|
'!MTREEONLY || !LOOKAHEAD',
|
|
'!MTREEONLY || !CKDATA',
|
|
]
|
|
code = '''
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
lfsr_mount(&lfs,
|
|
((RDONLY) ? LFS_M_RDONLY : LFS_M_RDWR)
|
|
| ((CKPROGS) ? LFS_IFDEF_CKPROGS(LFS_M_CKPROGS, -1) : 0)
|
|
| ((CKREADS) ? LFS_IFDEF_CKREADS(LFS_M_CKREADS, -1) : 0)
|
|
| ((CKFETCHES) ? LFS_IFDEF_CKFETCHES(LFS_M_CKFETCHES, -1) : 0)
|
|
| ((FLUSH) ? LFS_M_FLUSH : 0)
|
|
| ((SYNC) ? LFS_M_SYNC : 0)
|
|
| ((MTREEONLY) ? LFS_M_MTREEONLY : 0)
|
|
| ((MKCONSISTENT) ? LFS_M_MKCONSISTENT : 0)
|
|
| ((LOOKAHEAD) ? LFS_M_LOOKAHEAD : 0)
|
|
| ((COMPACT) ? LFS_M_COMPACT : 0)
|
|
| ((CKMETA) ? LFS_M_CKMETA : 0)
|
|
| ((CKDATA) ? LFS_M_CKDATA : 0),
|
|
CFG) => 0;
|
|
|
|
// lfsr_fs_stat only returns some flags
|
|
struct lfs_fsinfo fsinfo;
|
|
lfsr_fs_stat(&lfs, &fsinfo) => 0;
|
|
assert(fsinfo.flags == (
|
|
((RDONLY) ? LFS_I_RDONLY : 0)
|
|
| ((CKPROGS) ? LFS_IFDEF_CKPROGS(LFS_I_CKPROGS, -1) : 0)
|
|
| ((CKREADS) ? LFS_IFDEF_CKREADS(LFS_I_CKREADS, -1) : 0)
|
|
| ((CKFETCHES) ? LFS_IFDEF_CKFETCHES(LFS_I_CKFETCHES, -1) : 0)
|
|
| ((FLUSH) ? LFS_I_FLUSH : 0)
|
|
| ((SYNC) ? LFS_I_SYNC : 0)
|
|
| ((!LOOKAHEAD) ? LFS_I_CANLOOKAHEAD : 0)
|
|
| ((!COMPACT) ? LFS_I_UNCOMPACTED : 0)));
|
|
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
# test that various format flags don't, uh, assert or anything
|
|
#
|
|
# these end up passed to mount internally
|
|
[cases.test_mount_format_flags]
|
|
defines.CKPROGS = [false, true]
|
|
defines.CKREADS = [false, true]
|
|
defines.CKFETCHES = [false, true]
|
|
defines.MTREEONLY = [false, true]
|
|
defines.COMPACT = [false, true]
|
|
defines.CKMETA = [false, true]
|
|
defines.CKDATA = [false, true]
|
|
if = [
|
|
'LFS_IFDEF_CKPROGS(true, !CKPROGS)',
|
|
'LFS_IFDEF_CKREADS(true, !CKREADS)',
|
|
'LFS_IFDEF_CKFETCHES(true, !CKFETCHES)',
|
|
'!MTREEONLY || !CKDATA',
|
|
]
|
|
code = '''
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs,
|
|
LFS_F_RDWR
|
|
| ((CKPROGS) ? LFS_IFDEF_CKPROGS(LFS_F_CKPROGS, -1) : 0)
|
|
| ((CKREADS) ? LFS_IFDEF_CKREADS(LFS_F_CKREADS, -1) : 0)
|
|
| ((CKFETCHES) ? LFS_IFDEF_CKFETCHES(LFS_F_CKFETCHES, -1) : 0)
|
|
| ((MTREEONLY) ? LFS_M_MTREEONLY : 0)
|
|
| ((COMPACT) ? LFS_M_COMPACT : 0)
|
|
| ((CKMETA) ? LFS_M_CKMETA : 0)
|
|
| ((CKDATA) ? LFS_M_CKDATA : 0),
|
|
CFG) => 0;
|
|
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
|
|
# test that on-mount traversals do what they say they do
|
|
|
|
[cases.test_mount_t_lookahead]
|
|
defines.CKMETA = [false, true]
|
|
defines.CKDATA = [false, true]
|
|
code = '''
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// by default we need a lookahead scan
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
struct lfs_fsinfo fsinfo;
|
|
lfsr_fs_stat(&lfs, &fsinfo) => 0;
|
|
assert(fsinfo.flags == (
|
|
LFS_I_CANLOOKAHEAD
|
|
| LFS_I_UNCOMPACTED));
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// with LFS_M_LOOKAHEAD, mount performs a lookahead scan
|
|
lfsr_mount(&lfs,
|
|
LFS_M_RDWR
|
|
| LFS_M_LOOKAHEAD
|
|
| ((CKMETA) ? LFS_M_CKMETA : 0)
|
|
| ((CKDATA) ? LFS_M_CKDATA : 0),
|
|
CFG) => 0;
|
|
lfsr_fs_stat(&lfs, &fsinfo) => 0;
|
|
assert(fsinfo.flags == LFS_I_UNCOMPACTED);
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
[cases.test_mount_t_compact]
|
|
defines.LOOKAHEAD = [false, true]
|
|
defines.CKMETA = [false, true]
|
|
defines.CKDATA = [false, true]
|
|
defines.SIZE = [
|
|
'FILE_BUFFER_SIZE/2',
|
|
'2*FILE_BUFFER_SIZE',
|
|
'BLOCK_SIZE/2',
|
|
'BLOCK_SIZE',
|
|
'2*BLOCK_SIZE',
|
|
'8*BLOCK_SIZE',
|
|
]
|
|
# set compact thresh to minimum
|
|
defines.GC_COMPACT_THRESH = 'BLOCK_SIZE/2'
|
|
code = '''
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
uint32_t prng = 42;
|
|
|
|
// first lets create a compactable filesystem
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
|
|
// write to our mdir until >gc_compact_thresh full
|
|
lfsr_file_t file;
|
|
lfsr_file_open(&lfs, &file, "jellyfish",
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
|
|
// hack, don't use the internals like this
|
|
uint8_t wbuf[SIZE];
|
|
while ((file.o.o.mdir.rbyd.eoff & 0x7fffffff) <= GC_COMPACT_THRESH) {
|
|
lfsr_file_rewind(&lfs, &file) => 0;
|
|
for (lfs_size_t j = 0; j < SIZE; j++) {
|
|
wbuf[j] = 'a' + (TEST_PRNG(&prng) % 26);
|
|
}
|
|
lfsr_file_write(&lfs, &file, wbuf, SIZE) => SIZE;
|
|
lfsr_file_sync(&lfs, &file) => 0;
|
|
}
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// by default mount does not compact
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
struct lfs_fsinfo fsinfo;
|
|
lfsr_fs_stat(&lfs, &fsinfo) => 0;
|
|
assert(fsinfo.flags == (
|
|
LFS_I_CANLOOKAHEAD
|
|
| LFS_I_UNCOMPACTED));
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// with LFS_M_COMPACT, mount compact any uncompacted blocks
|
|
lfsr_mount(&lfs,
|
|
LFS_M_RDWR
|
|
| LFS_M_COMPACT
|
|
| ((LOOKAHEAD) ? LFS_M_LOOKAHEAD : 0)
|
|
| ((CKMETA) ? LFS_M_CKMETA : 0)
|
|
| ((CKDATA) ? LFS_M_CKDATA : 0),
|
|
CFG) => 0;
|
|
lfsr_fs_stat(&lfs, &fsinfo) => 0;
|
|
assert(fsinfo.flags == ((!LOOKAHEAD) ? LFS_I_CANLOOKAHEAD : 0));
|
|
|
|
// mdir should have been compacted
|
|
lfsr_file_open(&lfs, &file, "jellyfish", LFS_O_RDONLY) => 0;
|
|
assert((file.o.o.mdir.rbyd.eoff & 0x7fffffff) <= GC_COMPACT_THRESH);
|
|
|
|
// check we can still read the file
|
|
uint8_t rbuf[SIZE];
|
|
lfsr_file_read(&lfs, &file, rbuf, SIZE) => SIZE;
|
|
assert(memcmp(rbuf, wbuf, SIZE) == 0);
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
[cases.test_mount_t_mkconsistent]
|
|
defines.LOOKAHEAD = [false, true]
|
|
defines.COMPACT = [false, true]
|
|
defines.CKMETA = [false, true]
|
|
defines.CKDATA = [false, true]
|
|
defines.SIZE = 'FILE_BUFFER_SIZE/2'
|
|
# <=2 => grm-able
|
|
# >2 => requires orphans
|
|
defines.ORPHANS = [0, 1, 2, 3, 100]
|
|
code = '''
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
uint32_t prng = 42;
|
|
|
|
// first lets create some orphans
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
|
|
// create two files
|
|
lfsr_file_t file;
|
|
lfsr_file_open(&lfs, &file, "cuttlefish",
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
uint8_t wbuf1[SIZE];
|
|
for (lfs_size_t j = 0; j < SIZE; j++) {
|
|
wbuf1[j] = 'a' + (TEST_PRNG(&prng) % 26);
|
|
}
|
|
lfsr_file_write(&lfs, &file, wbuf1, SIZE) => SIZE;
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
|
|
lfsr_file_open(&lfs, &file, "octopus",
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
uint8_t wbuf2[SIZE];
|
|
for (lfs_size_t j = 0; j < SIZE; j++) {
|
|
wbuf2[j] = 'a' + (TEST_PRNG(&prng) % 26);
|
|
}
|
|
lfsr_file_write(&lfs, &file, wbuf2, SIZE) => SIZE;
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
|
|
// create this many orphaned files
|
|
//
|
|
// anytime we close a not-yet-created desync file, we create an
|
|
// orphan, but note we need these to be different files, and we need
|
|
// to close them after all open calls, otherwise we just end up with
|
|
// one orphan (littlefs is eager to clean up orphans)
|
|
//
|
|
lfsr_file_t orphans[ORPHANS];
|
|
for (lfs_size_t i = 0; i < ORPHANS; i++) {
|
|
char name[256];
|
|
sprintf(name, "jellyfish%03x", i);
|
|
lfsr_file_open(&lfs, &orphans[i], name,
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL | LFS_O_DESYNC) => 0;
|
|
}
|
|
for (lfs_size_t i = 0; i < ORPHANS; i++) {
|
|
lfsr_file_close(&lfs, &orphans[i]) => 0;
|
|
}
|
|
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// by default we clean up orphans lazily
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
struct lfs_fsinfo fsinfo;
|
|
lfsr_fs_stat(&lfs, &fsinfo) => 0;
|
|
assert(fsinfo.flags == (
|
|
((ORPHANS > 0) ? LFS_I_INCONSISTENT : 0)
|
|
| LFS_I_CANLOOKAHEAD
|
|
| LFS_I_UNCOMPACTED));
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// with LFS_M_MKCONSISTENT, mount cleans up orphans eagerly
|
|
lfsr_mount(&lfs,
|
|
LFS_M_RDWR
|
|
| LFS_M_MKCONSISTENT
|
|
| ((LOOKAHEAD) ? LFS_M_LOOKAHEAD : 0)
|
|
| ((COMPACT) ? LFS_M_COMPACT : 0)
|
|
| ((CKMETA) ? LFS_M_CKMETA : 0)
|
|
| ((CKDATA) ? LFS_M_CKDATA : 0),
|
|
CFG) => 0;
|
|
lfsr_fs_stat(&lfs, &fsinfo) => 0;
|
|
assert(fsinfo.flags == (
|
|
((!LOOKAHEAD) ? LFS_I_CANLOOKAHEAD : 0)
|
|
| ((!COMPACT) ? LFS_I_UNCOMPACTED : 0)));
|
|
|
|
// check we can still read the files
|
|
lfsr_file_open(&lfs, &file, "cuttlefish", LFS_O_RDONLY) => 0;
|
|
uint8_t rbuf[SIZE];
|
|
lfsr_file_read(&lfs, &file, rbuf, SIZE) => SIZE;
|
|
assert(memcmp(rbuf, wbuf1, SIZE) == 0);
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
|
|
lfsr_file_open(&lfs, &file, "octopus", LFS_O_RDONLY) => 0;
|
|
lfsr_file_read(&lfs, &file, rbuf, SIZE) => SIZE;
|
|
assert(memcmp(rbuf, wbuf2, SIZE) == 0);
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
# test we can detect at least fully clobbered blocks
|
|
#
|
|
# these are tested more thoroughly in test_ck
|
|
[cases.test_mount_t_ckmeta]
|
|
defines.N = [1, 2, 4, 8, 16, 32, 64]
|
|
defines.SIZE = [
|
|
'0',
|
|
'FILE_BUFFER_SIZE/2',
|
|
'2*FILE_BUFFER_SIZE',
|
|
'BLOCK_SIZE/2',
|
|
'BLOCK_SIZE',
|
|
'2*BLOCK_SIZE',
|
|
'8*BLOCK_SIZE',
|
|
]
|
|
if = '(SIZE*N)/BLOCK_SIZE <= 32'
|
|
code = '''
|
|
lfs_block_t i = 0;
|
|
while (true) {
|
|
// a bit hacky, but this catches infinite loops
|
|
assert(i < 2*BLOCK_COUNT);
|
|
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
|
|
// create an interesting filesystem
|
|
uint32_t prng = 42;
|
|
for (lfs_size_t i = 0; i < N; i++) {
|
|
char name[256];
|
|
sprintf(name, "squid%03x", i);
|
|
|
|
uint8_t wbuf[SIZE];
|
|
for (lfs_size_t j = 0; j < SIZE; j++) {
|
|
wbuf[j] = 'a' + (TEST_PRNG(&prng) % 26);
|
|
}
|
|
|
|
lfsr_file_t file;
|
|
lfsr_file_open(&lfs, &file, name,
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
lfsr_file_write(&lfs, &file, wbuf, SIZE) => SIZE;
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
}
|
|
|
|
// traverse to find blocks
|
|
lfsr_traversal_t t;
|
|
lfsr_traversal_open(&lfs, &t, 0) => 0;
|
|
lfs_block_t k = 0;
|
|
for (lfs_block_t j = 0;; j++) {
|
|
assert(j < 2*BLOCK_COUNT);
|
|
|
|
struct lfs_tinfo tinfo;
|
|
int err = lfsr_traversal_read(&lfs, &t, &tinfo);
|
|
assert(!err || err == LFS_ERR_NOENT);
|
|
if (err == LFS_ERR_NOENT) {
|
|
lfsr_traversal_close(&lfs, &t) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
goto done;
|
|
}
|
|
|
|
// this gets a bit tricky be cause we need to clobber both
|
|
// blocks in mdir pairs
|
|
if (tinfo.btype == LFS_BTYPE_MDIR
|
|
|| tinfo.btype == LFS_BTYPE_BTREE) {
|
|
if (k == i || k == i+1) {
|
|
// clobber this block
|
|
printf("clobbering 0x%x\n", tinfo.block);
|
|
uint8_t clobber_buf[BLOCK_SIZE];
|
|
memset(clobber_buf, 0xcc, BLOCK_SIZE);
|
|
CFG->erase(CFG, tinfo.block) => 0;
|
|
CFG->prog(CFG, tinfo.block, 0,
|
|
clobber_buf, BLOCK_SIZE) => 0;
|
|
if (tinfo.btype != LFS_BTYPE_MDIR || k == i+1) {
|
|
i += (tinfo.btype == LFS_BTYPE_MDIR) ? 2 : 1;
|
|
lfsr_traversal_close(&lfs, &t) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
goto clobbered;
|
|
}
|
|
}
|
|
k += 1;
|
|
}
|
|
}
|
|
|
|
clobbered:;
|
|
// mount with LFS_M_CKMETA, we should detect clobbered blocks
|
|
lfsr_mount(&lfs,
|
|
LFS_M_RDWR
|
|
| LFS_M_CKMETA,
|
|
CFG) => LFS_ERR_CORRUPT;
|
|
}
|
|
done:;
|
|
'''
|
|
|
|
[cases.test_mount_t_ckdata]
|
|
defines.N = [1, 2, 4, 8, 16, 32, 64]
|
|
defines.SIZE = [
|
|
'0',
|
|
'FILE_BUFFER_SIZE/2',
|
|
'2*FILE_BUFFER_SIZE',
|
|
'BLOCK_SIZE/2',
|
|
'BLOCK_SIZE',
|
|
'2*BLOCK_SIZE',
|
|
'8*BLOCK_SIZE',
|
|
]
|
|
if = '(SIZE*N)/BLOCK_SIZE <= 32'
|
|
code = '''
|
|
lfs_block_t i = 0;
|
|
while (true) {
|
|
// a bit hacky, but this catches infinite loops
|
|
assert(i < 2*BLOCK_COUNT);
|
|
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
|
|
// create an interesting filesystem
|
|
uint32_t prng = 42;
|
|
for (lfs_size_t i = 0; i < N; i++) {
|
|
char name[256];
|
|
sprintf(name, "squid%03x", i);
|
|
|
|
uint8_t wbuf[SIZE];
|
|
for (lfs_size_t j = 0; j < SIZE; j++) {
|
|
wbuf[j] = 'a' + (TEST_PRNG(&prng) % 26);
|
|
}
|
|
|
|
lfsr_file_t file;
|
|
lfsr_file_open(&lfs, &file, name,
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
lfsr_file_write(&lfs, &file, wbuf, SIZE) => SIZE;
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
}
|
|
|
|
// traverse to find blocks
|
|
lfsr_traversal_t t;
|
|
lfsr_traversal_open(&lfs, &t, 0) => 0;
|
|
lfs_block_t k = 0;
|
|
for (lfs_block_t j = 0;; j++) {
|
|
assert(j < 2*BLOCK_COUNT);
|
|
|
|
struct lfs_tinfo tinfo;
|
|
int err = lfsr_traversal_read(&lfs, &t, &tinfo);
|
|
assert(!err || err == LFS_ERR_NOENT);
|
|
if (err == LFS_ERR_NOENT) {
|
|
lfsr_traversal_close(&lfs, &t) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
goto done;
|
|
}
|
|
|
|
// this gets a bit tricky be cause we need to clobber both
|
|
// blocks in mdir pairs
|
|
if (tinfo.btype == LFS_BTYPE_MDIR
|
|
|| tinfo.btype == LFS_BTYPE_BTREE
|
|
|| tinfo.btype == LFS_BTYPE_DATA) {
|
|
if (k == i || k == i+1) {
|
|
// clobber this block
|
|
printf("clobbering 0x%x\n", tinfo.block);
|
|
uint8_t clobber_buf[BLOCK_SIZE];
|
|
memset(clobber_buf, 0xcc, BLOCK_SIZE);
|
|
CFG->erase(CFG, tinfo.block) => 0;
|
|
CFG->prog(CFG, tinfo.block, 0,
|
|
clobber_buf, BLOCK_SIZE) => 0;
|
|
if (tinfo.btype != LFS_BTYPE_MDIR || k == i+1) {
|
|
i += (tinfo.btype == LFS_BTYPE_MDIR) ? 2 : 1;
|
|
lfsr_traversal_close(&lfs, &t) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
goto clobbered;
|
|
}
|
|
}
|
|
k += 1;
|
|
}
|
|
}
|
|
|
|
clobbered:;
|
|
// mount with LFS_M_CKDATA, we should detect clobbered blocks
|
|
//
|
|
// note LFS_M_CKDATA implies LFS_M_CKMETA
|
|
lfsr_mount(&lfs,
|
|
LFS_M_RDWR
|
|
| LFS_M_CKDATA,
|
|
CFG) => LFS_ERR_CORRUPT;
|
|
}
|
|
done:;
|
|
'''
|
|
|
|
|
|
|
|
## incompatiblity tests ##
|
|
|
|
# test that we fail if we find no magic
|
|
[cases.test_mount_incompat_no_magic]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// delete the magic string
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_RM | LFSR_TAG_MAGIC, 0,
|
|
LFSR_DATA_NULL()))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_CORRUPT;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_CORRUPT;
|
|
'''
|
|
|
|
# test that we fail if we find bad magic
|
|
[cases.test_mount_incompat_bad_magic]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// tweak the magic string
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_MAGIC, 0,
|
|
LFSR_DATA_BUF("lottlefs", 8)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_CORRUPT;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_CORRUPT;
|
|
'''
|
|
|
|
# test that we fail to mount after a major version bump
|
|
[cases.test_mount_incompat_major]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// bump the major version
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_VERSION, 0,
|
|
LFSR_DATA_BUF(((const uint8_t[2]){
|
|
LFS_DISK_VERSION_MAJOR+1,
|
|
0}), 2)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test that we fail to mount after a minor version bump
|
|
[cases.test_mount_incompat_minor]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// bump the minor version
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_VERSION, 0,
|
|
LFSR_DATA_BUF(((const uint8_t[2]){
|
|
LFS_DISK_VERSION_MAJOR,
|
|
LFS_DISK_VERSION_MINOR+1}), 2)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test that we fail to mount incompatible rcompat flags
|
|
[cases.test_mount_incompat_rcompat]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set the nonstandard rcompat flag, this will always be incompatible
|
|
// with standard littlefs
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_RCOMPAT, 0,
|
|
LFSR_DATA_RCOMPAT(
|
|
LFSR_RCOMPAT_COMPAT
|
|
| LFSR_RCOMPAT_NONSTANDARD)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test that we fail to mount incompatible wcompat flags
|
|
[cases.test_mount_incompat_wcompat]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set the nonstandard rcompat flag, this will always be incompatible
|
|
// with standard littlefs
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_WCOMPAT, 0,
|
|
LFSR_DATA_WCOMPAT(
|
|
LFSR_WCOMPAT_COMPAT
|
|
| LFSR_WCOMPAT_NONSTANDARD)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
|
|
// but we _can_ mount readonly
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
# test that an incompatible ocompat flag is a noop
|
|
[cases.test_mount_incompat_ocompat]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set the nonstandard ocompat flag, this will always be incompatible
|
|
// with standard littlefs
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_OCOMPAT, 0,
|
|
LFSR_DATA_OCOMPAT(
|
|
LFSR_OCOMPAT_COMPAT
|
|
| LFSR_OCOMPAT_NONSTANDARD)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should _not_ fail, ocompat should always be ignored
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
# these are just a bit harder to detect
|
|
[cases.test_mount_incompat_rcompat_overflow]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set a really far rcompat flag
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR_CAT(
|
|
LFSR_TAG_RCOMPAT, 0,
|
|
LFSR_DATA_RCOMPAT(LFSR_RCOMPAT_COMPAT),
|
|
LFSR_DATA_BUF("\x00\x00\x00\x00\x80", 5)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
[cases.test_mount_incompat_wcompat_overflow]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set a really far wcompat flag
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR_CAT(
|
|
LFSR_TAG_WCOMPAT, 0,
|
|
LFSR_DATA_WCOMPAT(LFSR_WCOMPAT_COMPAT),
|
|
LFSR_DATA_BUF("\x00\x00\x00\x00\x80", 5)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
|
|
// but we _can_ mount readonly
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
[cases.test_mount_incompat_ocompat_overflow]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set a really far ocompat flag
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR_CAT(
|
|
LFSR_TAG_OCOMPAT, 0,
|
|
LFSR_DATA_OCOMPAT(LFSR_OCOMPAT_COMPAT),
|
|
LFSR_DATA_BUF("\x00\x00\x00\x00\x80", 5)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should _not_ fail, ocompat should always be ignored
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|
|
|
|
# test that we fail to mount incompatible block sizes
|
|
[cases.test_mount_incompat_block_size]
|
|
defines.INC_BLOCK_SIZE = ['BLOCK_SIZE/2', 'BLOCK_SIZE*2']
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set an incompatible block size
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_GEOMETRY, 0,
|
|
LFSR_DATA_GEOMETRY((&(lfsr_geometry_t){
|
|
INC_BLOCK_SIZE,
|
|
BLOCK_COUNT}))))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test that we fail to mount after incompatible block counts
|
|
[cases.test_mount_incompat_block_count]
|
|
defines.INC_BLOCK_COUNT = ['BLOCK_COUNT*2']
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set an incompatible block count
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_GEOMETRY, 0,
|
|
LFSR_DATA_GEOMETRY((&(lfsr_geometry_t){
|
|
BLOCK_SIZE,
|
|
INC_BLOCK_COUNT}))))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test that we fail to mount after incompatible name limit
|
|
[cases.test_mount_incompat_name_limit]
|
|
defines.INC_NAME_LIMIT = ['LFS_NAME_MAX*2']
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set an incompatible block size
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_NAMELIMIT, 0,
|
|
LFSR_DATA_LLEB128(INC_NAME_LIMIT)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test that we fail to mount after incompatible file limit
|
|
[cases.test_mount_incompat_file_limit]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// set an incompatible file limit
|
|
//
|
|
// note we're messing around with internals to do this! this
|
|
// is not a user API
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR_CAT(
|
|
LFSR_TAG_FILELIMIT, 0,
|
|
// it's a bit difficult to test this since file limit
|
|
// is usually our integer limit, but we can force a
|
|
// larger value by inserting an extra byte into our
|
|
// leb128 encoding
|
|
LFSR_DATA_BUF("\xff", 1),
|
|
LFSR_DATA_LEB128(LFS_FILE_MAX)))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test what happens if we find an unknown config
|
|
[cases.test_mount_incompat_unknown_config]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// create an unknown config
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_ATTRS(
|
|
LFSR_ATTR(
|
|
LFSR_TAG_CONFIG + 0x13, 0,
|
|
LFSR_DATA_BUF("oh no!", strlen("oh no!"))))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => LFS_ERR_NOTSUP;
|
|
'''
|
|
|
|
# test what happens if we find an unknown file type
|
|
[cases.test_mount_incompat_unknown_type]
|
|
in = 'lfs.c'
|
|
code = '''
|
|
// create a superblock
|
|
lfs_t lfs;
|
|
lfsr_format(&lfs, LFS_F_RDWR, CFG) => 0;
|
|
|
|
// create some files
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_file_t file;
|
|
lfsr_file_open(&lfs, &file, "a",
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
lfsr_file_write(&lfs, &file,
|
|
"hi a!", strlen("hi a!")) => strlen("hi a!");
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
lfsr_file_open(&lfs, &file, "b",
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
lfsr_file_write(&lfs, &file,
|
|
"oh no!", strlen("oh no!")) => strlen("oh no!");
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
lfsr_file_open(&lfs, &file, "c",
|
|
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
|
|
lfsr_file_write(&lfs, &file,
|
|
"hi c!", strlen("hi c!")) => strlen("hi c!");
|
|
lfsr_file_close(&lfs, &file) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// change a file's type to something unknown
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
|
|
lfsr_mdir_t mdir;
|
|
lfsr_did_t did;
|
|
const char *name;
|
|
lfs_size_t name_size;
|
|
lfsr_mtree_pathlookup(&lfs, "b",
|
|
&mdir, NULL,
|
|
&did, &name, &name_size) => LFS_ERR_EXIST;
|
|
lfsr_mdir_commit(&lfs, &mdir, LFSR_ATTRS(
|
|
LFSR_ATTR_NAME(
|
|
LFSR_TAG_SUB | (LFSR_TAG_NAME + 0x13), 0,
|
|
did, name, name_size))) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
|
|
// mount should now fail
|
|
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => LFS_ERR_NOTSUP;
|
|
|
|
// but we _can_ mount readonly
|
|
lfsr_mount(&lfs, LFS_M_RDONLY, CFG) => 0;
|
|
lfsr_unmount(&lfs) => 0;
|
|
'''
|