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Merge remote-tracking branch 'origin/devel' into fix-dir-seek-end

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This commit is contained in:
Christopher Haster
2023-04-26 13:47:58 -05:00
parent b33a5b3f85 92298c749d
commit b6773e68bf
67 changed files with 26381 additions and 5141 deletions
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lfs.c
+427 -180
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@@ -135,14 +135,14 @@ static int lfs_bd_cmp(lfs_t *lfs,
uint8_t dat[8];
diff = lfs_min(size-i, sizeof(dat));
int res = lfs_bd_read(lfs,
int err = lfs_bd_read(lfs,
pcache, rcache, hint-i,
block, off+i, &dat, diff);
if (res) {
return res;
if (err) {
return err;
}
res = memcmp(dat, data + i, diff);
int res = memcmp(dat, data + i, diff);
if (res) {
return res < 0 ? LFS_CMP_LT : LFS_CMP_GT;
}
@@ -151,6 +151,27 @@ static int lfs_bd_cmp(lfs_t *lfs,
return LFS_CMP_EQ;
}
static int lfs_bd_crc(lfs_t *lfs,
const lfs_cache_t *pcache, lfs_cache_t *rcache, lfs_size_t hint,
lfs_block_t block, lfs_off_t off, lfs_size_t size, uint32_t *crc) {
lfs_size_t diff = 0;
for (lfs_off_t i = 0; i < size; i += diff) {
uint8_t dat[8];
diff = lfs_min(size-i, sizeof(dat));
int err = lfs_bd_read(lfs,
pcache, rcache, hint-i,
block, off+i, &dat, diff);
if (err) {
return err;
}
*crc = lfs_crc(*crc, &dat, diff);
}
return 0;
}
#ifndef LFS_READONLY
static int lfs_bd_flush(lfs_t *lfs,
lfs_cache_t *pcache, lfs_cache_t *rcache, bool validate) {
@@ -279,14 +300,12 @@ static inline int lfs_pair_cmp(
paira[0] == pairb[1] || paira[1] == pairb[0]);
}
#ifndef LFS_READONLY
static inline bool lfs_pair_sync(
static inline bool lfs_pair_issync(
const lfs_block_t paira[2],
const lfs_block_t pairb[2]) {
return (paira[0] == pairb[0] && paira[1] == pairb[1]) ||
(paira[0] == pairb[1] && paira[1] == pairb[0]);
}
#endif
static inline void lfs_pair_fromle32(lfs_block_t pair[2]) {
pair[0] = lfs_fromle32(pair[0]);
@@ -325,6 +344,10 @@ static inline uint16_t lfs_tag_type1(lfs_tag_t tag) {
return (tag & 0x70000000) >> 20;
}
static inline uint16_t lfs_tag_type2(lfs_tag_t tag) {
return (tag & 0x78000000) >> 20;
}
static inline uint16_t lfs_tag_type3(lfs_tag_t tag) {
return (tag & 0x7ff00000) >> 20;
}
@@ -386,12 +409,16 @@ static inline bool lfs_gstate_hasorphans(const lfs_gstate_t *a) {
}
static inline uint8_t lfs_gstate_getorphans(const lfs_gstate_t *a) {
return lfs_tag_size(a->tag);
return lfs_tag_size(a->tag) & 0x1ff;
}
static inline bool lfs_gstate_hasmove(const lfs_gstate_t *a) {
return lfs_tag_type1(a->tag);
}
static inline bool lfs_gstate_needssuperblock(const lfs_gstate_t *a) {
return lfs_tag_size(a->tag) >> 9;
}
#endif
static inline bool lfs_gstate_hasmovehere(const lfs_gstate_t *a,
@@ -413,6 +440,24 @@ static inline void lfs_gstate_tole32(lfs_gstate_t *a) {
}
#endif
// operations on forward-CRCs used to track erased state
struct lfs_fcrc {
lfs_size_t size;
uint32_t crc;
};
static void lfs_fcrc_fromle32(struct lfs_fcrc *fcrc) {
fcrc->size = lfs_fromle32(fcrc->size);
fcrc->crc = lfs_fromle32(fcrc->crc);
}
#ifndef LFS_READONLY
static void lfs_fcrc_tole32(struct lfs_fcrc *fcrc) {
fcrc->size = lfs_tole32(fcrc->size);
fcrc->crc = lfs_tole32(fcrc->crc);
}
#endif
// other endianness operations
static void lfs_ctz_fromle32(struct lfs_ctz *ctz) {
ctz->head = lfs_fromle32(ctz->head);
@@ -490,6 +535,7 @@ static int lfs_file_outline(lfs_t *lfs, lfs_file_t *file);
static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file);
static int lfs_fs_deorphan(lfs_t *lfs, bool powerloss);
static void lfs_fs_prepsuperblock(lfs_t *lfs, bool needssuperblock);
static int lfs_fs_preporphans(lfs_t *lfs, int8_t orphans);
static void lfs_fs_prepmove(lfs_t *lfs,
uint16_t id, const lfs_block_t pair[2]);
@@ -1035,6 +1081,11 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
bool tempsplit = false;
lfs_stag_t tempbesttag = besttag;
// assume not erased until proven otherwise
bool maybeerased = false;
bool hasfcrc = false;
struct lfs_fcrc fcrc;
dir->rev = lfs_tole32(dir->rev);
uint32_t crc = lfs_crc(0xffffffff, &dir->rev, sizeof(dir->rev));
dir->rev = lfs_fromle32(dir->rev);
@@ -1049,7 +1100,6 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
if (err) {
if (err == LFS_ERR_CORRUPT) {
// can't continue?
dir->erased = false;
break;
}
return err;
@@ -1058,19 +1108,18 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
crc = lfs_crc(crc, &tag, sizeof(tag));
tag = lfs_frombe32(tag) ^ ptag;
// next commit not yet programmed or we're not in valid range
// next commit not yet programmed?
if (!lfs_tag_isvalid(tag)) {
dir->erased = (lfs_tag_type1(ptag) == LFS_TYPE_CRC &&
dir->off % lfs->cfg->prog_size == 0);
maybeerased = true;
break;
// out of range?
} else if (off + lfs_tag_dsize(tag) > lfs->cfg->block_size) {
dir->erased = false;
break;
}
ptag = tag;
if (lfs_tag_type1(tag) == LFS_TYPE_CRC) {
if (lfs_tag_type2(tag) == LFS_TYPE_CCRC) {
// check the crc attr
uint32_t dcrc;
err = lfs_bd_read(lfs,
@@ -1078,7 +1127,6 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
dir->pair[0], off+sizeof(tag), &dcrc, sizeof(dcrc));
if (err) {
if (err == LFS_ERR_CORRUPT) {
dir->erased = false;
break;
}
return err;
@@ -1086,7 +1134,6 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
dcrc = lfs_fromle32(dcrc);
if (crc != dcrc) {
dir->erased = false;
break;
}
@@ -1113,21 +1160,19 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
continue;
}
// crc the entry first, hopefully leaving it in the cache
for (lfs_off_t j = sizeof(tag); j < lfs_tag_dsize(tag); j++) {
uint8_t dat;
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off+j, &dat, 1);
if (err) {
if (err == LFS_ERR_CORRUPT) {
dir->erased = false;
break;
}
return err;
}
// fcrc is only valid when last tag was a crc
hasfcrc = false;
crc = lfs_crc(crc, &dat, 1);
// crc the entry first, hopefully leaving it in the cache
err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off+sizeof(tag),
lfs_tag_dsize(tag)-sizeof(tag), &crc);
if (err) {
if (err == LFS_ERR_CORRUPT) {
break;
}
return err;
}
// directory modification tags?
@@ -1154,12 +1199,24 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
dir->pair[0], off+sizeof(tag), &temptail, 8);
if (err) {
if (err == LFS_ERR_CORRUPT) {
dir->erased = false;
break;
}
return err;
}
lfs_pair_fromle32(temptail);
} else if (lfs_tag_type3(tag) == LFS_TYPE_FCRC) {
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off+sizeof(tag),
&fcrc, sizeof(fcrc));
if (err) {
if (err == LFS_ERR_CORRUPT) {
break;
}
}
lfs_fcrc_fromle32(&fcrc);
hasfcrc = true;
}
// found a match for our fetcher?
@@ -1168,7 +1225,6 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
dir->pair[0], off+sizeof(tag)});
if (res < 0) {
if (res == LFS_ERR_CORRUPT) {
dir->erased = false;
break;
}
return res;
@@ -1190,35 +1246,54 @@ static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
}
}
// consider what we have good enough
if (dir->off > 0) {
// synthetic move
if (lfs_gstate_hasmovehere(&lfs->gdisk, dir->pair)) {
if (lfs_tag_id(lfs->gdisk.tag) == lfs_tag_id(besttag)) {
besttag |= 0x80000000;
} else if (besttag != -1 &&
lfs_tag_id(lfs->gdisk.tag) < lfs_tag_id(besttag)) {
besttag -= LFS_MKTAG(0, 1, 0);
}
// found no valid commits?
if (dir->off == 0) {
// try the other block?
lfs_pair_swap(dir->pair);
dir->rev = revs[(r+1)%2];
continue;
}
// did we end on a valid commit? we may have an erased block
dir->erased = false;
if (maybeerased && hasfcrc && dir->off % lfs->cfg->prog_size == 0) {
// check for an fcrc matching the next prog's erased state, if
// this failed most likely a previous prog was interrupted, we
// need a new erase
uint32_t fcrc_ = 0xffffffff;
int err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], dir->off, fcrc.size, &fcrc_);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
// found tag? or found best id?
if (id) {
*id = lfs_min(lfs_tag_id(besttag), dir->count);
}
// found beginning of erased part?
dir->erased = (fcrc_ == fcrc.crc);
}
if (lfs_tag_isvalid(besttag)) {
return besttag;
} else if (lfs_tag_id(besttag) < dir->count) {
return LFS_ERR_NOENT;
} else {
return 0;
// synthetic move
if (lfs_gstate_hasmovehere(&lfs->gdisk, dir->pair)) {
if (lfs_tag_id(lfs->gdisk.tag) == lfs_tag_id(besttag)) {
besttag |= 0x80000000;
} else if (besttag != -1 &&
lfs_tag_id(lfs->gdisk.tag) < lfs_tag_id(besttag)) {
besttag -= LFS_MKTAG(0, 1, 0);
}
}
// failed, try the other block?
lfs_pair_swap(dir->pair);
dir->rev = revs[(r+1)%2];
// found tag? or found best id?
if (id) {
*id = lfs_min(lfs_tag_id(besttag), dir->count);
}
if (lfs_tag_isvalid(besttag)) {
return besttag;
} else if (lfs_tag_id(besttag) < dir->count) {
return LFS_ERR_NOENT;
} else {
return 0;
}
}
LFS_ERROR("Corrupted dir pair at {0x%"PRIx32", 0x%"PRIx32"}",
@@ -1492,9 +1567,15 @@ static int lfs_dir_commitattr(lfs_t *lfs, struct lfs_commit *commit,
#endif
#ifndef LFS_READONLY
static int lfs_dir_commitcrc(lfs_t *lfs, struct lfs_commit *commit) {
// align to program units
const lfs_off_t end = lfs_alignup(commit->off + 2*sizeof(uint32_t),
//
// this gets a bit complex as we have two types of crcs:
// - 5-word crc with fcrc to check following prog (middle of block)
// - 2-word crc with no following prog (end of block)
const lfs_off_t end = lfs_alignup(
lfs_min(commit->off + 5*sizeof(uint32_t), lfs->cfg->block_size),
lfs->cfg->prog_size);
lfs_off_t off1 = 0;
@@ -1504,89 +1585,116 @@ static int lfs_dir_commitcrc(lfs_t *lfs, struct lfs_commit *commit) {
// padding is not crced, which lets fetches skip padding but
// makes committing a bit more complicated
while (commit->off < end) {
lfs_off_t off = commit->off + sizeof(lfs_tag_t);
lfs_off_t noff = lfs_min(end - off, 0x3fe) + off;
lfs_off_t noff = (
lfs_min(end - (commit->off+sizeof(lfs_tag_t)), 0x3fe)
+ (commit->off+sizeof(lfs_tag_t)));
// too large for crc tag? need padding commits
if (noff < end) {
noff = lfs_min(noff, end - 2*sizeof(uint32_t));
noff = lfs_min(noff, end - 5*sizeof(uint32_t));
}
// read erased state from next program unit
lfs_tag_t tag = 0xffffffff;
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, sizeof(tag),
commit->block, noff, &tag, sizeof(tag));
if (err && err != LFS_ERR_CORRUPT) {
return err;
// space for fcrc?
uint8_t eperturb = -1;
if (noff >= end && noff <= lfs->cfg->block_size - lfs->cfg->prog_size) {
// first read the leading byte, this always contains a bit
// we can perturb to avoid writes that don't change the fcrc
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->prog_size,
commit->block, noff, &eperturb, 1);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
// find the expected fcrc, don't bother avoiding a reread
// of the eperturb, it should still be in our cache
struct lfs_fcrc fcrc = {.size=lfs->cfg->prog_size, .crc=0xffffffff};
err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, lfs->cfg->prog_size,
commit->block, noff, fcrc.size, &fcrc.crc);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
lfs_fcrc_tole32(&fcrc);
err = lfs_dir_commitattr(lfs, commit,
LFS_MKTAG(LFS_TYPE_FCRC, 0x3ff, sizeof(struct lfs_fcrc)),
&fcrc);
if (err) {
return err;
}
}
// build crc tag
bool reset = ~lfs_frombe32(tag) >> 31;
tag = LFS_MKTAG(LFS_TYPE_CRC + reset, 0x3ff, noff - off);
// build commit crc
struct {
lfs_tag_t tag;
uint32_t crc;
} ccrc;
lfs_tag_t ntag = LFS_MKTAG(
LFS_TYPE_CCRC + (((uint8_t)~eperturb) >> 7), 0x3ff,
noff - (commit->off+sizeof(lfs_tag_t)));
ccrc.tag = lfs_tobe32(ntag ^ commit->ptag);
commit->crc = lfs_crc(commit->crc, &ccrc.tag, sizeof(lfs_tag_t));
ccrc.crc = lfs_tole32(commit->crc);
// write out crc
uint32_t footer[2];
footer[0] = lfs_tobe32(tag ^ commit->ptag);
commit->crc = lfs_crc(commit->crc, &footer[0], sizeof(footer[0]));
footer[1] = lfs_tole32(commit->crc);
err = lfs_bd_prog(lfs,
int err = lfs_bd_prog(lfs,
&lfs->pcache, &lfs->rcache, false,
commit->block, commit->off, &footer, sizeof(footer));
commit->block, commit->off, &ccrc, sizeof(ccrc));
if (err) {
return err;
}
// keep track of non-padding checksum to verify
if (off1 == 0) {
off1 = commit->off + sizeof(uint32_t);
off1 = commit->off + sizeof(lfs_tag_t);
crc1 = commit->crc;
}
commit->off += sizeof(tag)+lfs_tag_size(tag);
commit->ptag = tag ^ ((lfs_tag_t)reset << 31);
commit->crc = 0xffffffff; // reset crc for next "commit"
commit->off = noff;
// perturb valid bit?
commit->ptag = ntag ^ ((0x80 & ~eperturb) << 24);
// reset crc for next commit
commit->crc = 0xffffffff;
// manually flush here since we don't prog the padding, this confuses
// the caching layer
if (noff >= end || noff >= lfs->pcache.off + lfs->cfg->cache_size) {
// flush buffers
int err = lfs_bd_sync(lfs, &lfs->pcache, &lfs->rcache, false);
if (err) {
return err;
}
}
}
// flush buffers
int err = lfs_bd_sync(lfs, &lfs->pcache, &lfs->rcache, false);
// successful commit, check checksums to make sure
//
// note that we don't need to check padding commits, worst
// case if they are corrupted we would have had to compact anyways
lfs_off_t off = commit->begin;
uint32_t crc = 0xffffffff;
int err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, off1+sizeof(uint32_t),
commit->block, off, off1-off, &crc);
if (err) {
return err;
}
// successful commit, check checksums to make sure
lfs_off_t off = commit->begin;
lfs_off_t noff = off1;
while (off < end) {
uint32_t crc = 0xffffffff;
for (lfs_off_t i = off; i < noff+sizeof(uint32_t); i++) {
// check against written crc, may catch blocks that
// become readonly and match our commit size exactly
if (i == off1 && crc != crc1) {
return LFS_ERR_CORRUPT;
}
// check non-padding commits against known crc
if (crc != crc1) {
return LFS_ERR_CORRUPT;
}
// leave it up to caching to make this efficient
uint8_t dat;
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, noff+sizeof(uint32_t)-i,
commit->block, i, &dat, 1);
if (err) {
return err;
}
// make sure to check crc in case we happen to pick
// up an unrelated crc (frozen block?)
err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, sizeof(uint32_t),
commit->block, off1, sizeof(uint32_t), &crc);
if (err) {
return err;
}
crc = lfs_crc(crc, &dat, 1);
}
// detected write error?
if (crc != 0) {
return LFS_ERR_CORRUPT;
}
// skip padding
off = lfs_min(end - noff, 0x3fe) + noff;
if (off < end) {
off = lfs_min(off, end - 2*sizeof(uint32_t));
}
noff = off + sizeof(uint32_t);
if (crc != 0) {
return LFS_ERR_CORRUPT;
}
return 0;
@@ -1927,11 +2035,20 @@ static int lfs_dir_splittingcompact(lfs_t *lfs, lfs_mdir_t *dir,
return err;
}
// space is complicated, we need room for tail, crc, gstate,
// cleanup delete, and we cap at half a block to give room
// for metadata updates.
// space is complicated, we need room for:
//
// - tail: 4+2*4 = 12 bytes
// - gstate: 4+3*4 = 16 bytes
// - move delete: 4 = 4 bytes
// - crc: 4+4 = 8 bytes
// total = 40 bytes
//
// And we cap at half a block to avoid degenerate cases with
// nearly-full metadata blocks.
//
if (end - split < 0xff
&& size <= lfs_min(lfs->cfg->block_size - 36,
&& size <= lfs_min(
lfs->cfg->block_size - 40,
lfs_alignup(
(lfs->cfg->metadata_max
? lfs->cfg->metadata_max
@@ -3905,6 +4022,12 @@ static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
lfs->cfg = cfg;
int err = 0;
// check that bool is a truthy-preserving type
//
// note the most common reason for this failure is a before-c99 compiler,
// which littlefs currently does not support
LFS_ASSERT((bool)0x80000000);
// validate that the lfs-cfg sizes were initiated properly before
// performing any arithmetic logics with them
LFS_ASSERT(lfs->cfg->read_size != 0);
@@ -3917,7 +4040,10 @@ static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
LFS_ASSERT(lfs->cfg->cache_size % lfs->cfg->prog_size == 0);
LFS_ASSERT(lfs->cfg->block_size % lfs->cfg->cache_size == 0);
// check that the block size is large enough to fit ctz pointers
// check that the block size is large enough to fit all ctz pointers
LFS_ASSERT(lfs->cfg->block_size >= 128);
// this is the exact calculation for all ctz pointers, if this fails
// and the simpler assert above does not, math must be broken
LFS_ASSERT(4*lfs_npw2(0xffffffff / (lfs->cfg->block_size-2*4))
<= lfs->cfg->block_size);
@@ -4101,14 +4227,23 @@ static int lfs_rawmount(lfs_t *lfs, const struct lfs_config *cfg) {
// scan directory blocks for superblock and any global updates
lfs_mdir_t dir = {.tail = {0, 1}};
lfs_block_t cycle = 0;
lfs_block_t tortoise[2] = {LFS_BLOCK_NULL, LFS_BLOCK_NULL};
lfs_size_t tortoise_i = 1;
lfs_size_t tortoise_period = 1;
while (!lfs_pair_isnull(dir.tail)) {
if (cycle >= lfs->cfg->block_count/2) {
// loop detected
// detect cycles with Brent's algorithm
if (lfs_pair_issync(dir.tail, tortoise)) {
LFS_WARN("Cycle detected in tail list");
err = LFS_ERR_CORRUPT;
goto cleanup;
}
cycle += 1;
if (tortoise_i == tortoise_period) {
tortoise[0] = dir.tail[0];
tortoise[1] = dir.tail[1];
tortoise_i = 0;
tortoise_period *= 2;
}
tortoise_i += 1;
// fetch next block in tail list
lfs_stag_t tag = lfs_dir_fetchmatch(lfs, &dir, dir.tail,
@@ -4144,12 +4279,29 @@ static int lfs_rawmount(lfs_t *lfs, const struct lfs_config *cfg) {
uint16_t minor_version = (0xffff & (superblock.version >> 0));
if ((major_version != LFS_DISK_VERSION_MAJOR ||
minor_version > LFS_DISK_VERSION_MINOR)) {
LFS_ERROR("Invalid version v%"PRIu16".%"PRIu16,
major_version, minor_version);
LFS_ERROR("Invalid version "
"v%"PRIu16".%"PRIu16" != v%"PRIu16".%"PRIu16,
major_version, minor_version,
LFS_DISK_VERSION_MAJOR, LFS_DISK_VERSION_MINOR);
err = LFS_ERR_INVAL;
goto cleanup;
}
// found older minor version? set an in-device only bit in the
// gstate so we know we need to rewrite the superblock before
// the first write
if (minor_version < LFS_DISK_VERSION_MINOR) {
LFS_DEBUG("Found older minor version "
"v%"PRIu16".%"PRIu16" < v%"PRIu16".%"PRIu16,
major_version, minor_version,
LFS_DISK_VERSION_MAJOR, LFS_DISK_VERSION_MINOR);
#ifndef LFS_READONLY
// note this bit is reserved on disk, so fetching more gstate
// will not interfere here
lfs_fs_prepsuperblock(lfs, true);
#endif
}
// check superblock configuration
if (superblock.name_max) {
if (superblock.name_max > lfs->name_max) {
@@ -4259,13 +4411,22 @@ int lfs_fs_rawtraverse(lfs_t *lfs,
}
#endif
lfs_block_t cycle = 0;
lfs_block_t tortoise[2] = {LFS_BLOCK_NULL, LFS_BLOCK_NULL};
lfs_size_t tortoise_i = 1;
lfs_size_t tortoise_period = 1;
while (!lfs_pair_isnull(dir.tail)) {
if (cycle >= lfs->cfg->block_count/2) {
// loop detected
// detect cycles with Brent's algorithm
if (lfs_pair_issync(dir.tail, tortoise)) {
LFS_WARN("Cycle detected in tail list");
return LFS_ERR_CORRUPT;
}
cycle += 1;
if (tortoise_i == tortoise_period) {
tortoise[0] = dir.tail[0];
tortoise[1] = dir.tail[1];
tortoise_i = 0;
tortoise_period *= 2;
}
tortoise_i += 1;
for (int i = 0; i < 2; i++) {
int err = cb(data, dir.tail[i]);
@@ -4344,13 +4505,22 @@ static int lfs_fs_pred(lfs_t *lfs,
// iterate over all directory directory entries
pdir->tail[0] = 0;
pdir->tail[1] = 1;
lfs_block_t cycle = 0;
lfs_block_t tortoise[2] = {LFS_BLOCK_NULL, LFS_BLOCK_NULL};
lfs_size_t tortoise_i = 1;
lfs_size_t tortoise_period = 1;
while (!lfs_pair_isnull(pdir->tail)) {
if (cycle >= lfs->cfg->block_count/2) {
// loop detected
// detect cycles with Brent's algorithm
if (lfs_pair_issync(pdir->tail, tortoise)) {
LFS_WARN("Cycle detected in tail list");
return LFS_ERR_CORRUPT;
}
cycle += 1;
if (tortoise_i == tortoise_period) {
tortoise[0] = pdir->tail[0];
tortoise[1] = pdir->tail[1];
tortoise_i = 0;
tortoise_period *= 2;
}
tortoise_i += 1;
if (lfs_pair_cmp(pdir->tail, pair) == 0) {
return 0;
@@ -4400,13 +4570,22 @@ static lfs_stag_t lfs_fs_parent(lfs_t *lfs, const lfs_block_t pair[2],
// use fetchmatch with callback to find pairs
parent->tail[0] = 0;
parent->tail[1] = 1;
lfs_block_t cycle = 0;
lfs_block_t tortoise[2] = {LFS_BLOCK_NULL, LFS_BLOCK_NULL};
lfs_size_t tortoise_i = 1;
lfs_size_t tortoise_period = 1;
while (!lfs_pair_isnull(parent->tail)) {
if (cycle >= lfs->cfg->block_count/2) {
// loop detected
// detect cycles with Brent's algorithm
if (lfs_pair_issync(parent->tail, tortoise)) {
LFS_WARN("Cycle detected in tail list");
return LFS_ERR_CORRUPT;
}
cycle += 1;
if (tortoise_i == tortoise_period) {
tortoise[0] = parent->tail[0];
tortoise[1] = parent->tail[1];
tortoise_i = 0;
tortoise_period *= 2;
}
tortoise_i += 1;
lfs_stag_t tag = lfs_dir_fetchmatch(lfs, parent, parent->tail,
LFS_MKTAG(0x7ff, 0, 0x3ff),
@@ -4423,9 +4602,17 @@ static lfs_stag_t lfs_fs_parent(lfs_t *lfs, const lfs_block_t pair[2],
}
#endif
#ifndef LFS_READONLY
static void lfs_fs_prepsuperblock(lfs_t *lfs, bool needssuperblock) {
lfs->gstate.tag = (lfs->gstate.tag & ~LFS_MKTAG(0, 0, 0x200))
| (uint32_t)needssuperblock << 9;
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_preporphans(lfs_t *lfs, int8_t orphans) {
LFS_ASSERT(lfs_tag_size(lfs->gstate.tag) > 0 || orphans >= 0);
LFS_ASSERT(lfs_tag_size(lfs->gstate.tag) > 0x000 || orphans >= 0);
LFS_ASSERT(lfs_tag_size(lfs->gstate.tag) < 0x1ff || orphans <= 0);
lfs->gstate.tag += orphans;
lfs->gstate.tag = ((lfs->gstate.tag & ~LFS_MKTAG(0x800, 0, 0)) |
((uint32_t)lfs_gstate_hasorphans(&lfs->gstate) << 31));
@@ -4444,6 +4631,45 @@ static void lfs_fs_prepmove(lfs_t *lfs,
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_desuperblock(lfs_t *lfs) {
if (!lfs_gstate_needssuperblock(&lfs->gstate)) {
return 0;
}
LFS_DEBUG("Rewriting superblock {0x%"PRIx32", 0x%"PRIx32"}",
lfs->root[0],
lfs->root[1]);
lfs_mdir_t root;
int err = lfs_dir_fetch(lfs, &root, lfs->root);
if (err) {
return err;
}
// write a new superblock
lfs_superblock_t superblock = {
.version = LFS_DISK_VERSION,
.block_size = lfs->cfg->block_size,
.block_count = lfs->cfg->block_count,
.name_max = lfs->name_max,
.file_max = lfs->file_max,
.attr_max = lfs->attr_max,
};
lfs_superblock_tole32(&superblock);
err = lfs_dir_commit(lfs, &root, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, sizeof(superblock)),
&superblock}));
if (err) {
return err;
}
lfs_fs_prepsuperblock(lfs, false);
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_demove(lfs_t *lfs) {
if (!lfs_gstate_hasmove(&lfs->gdisk)) {
@@ -4456,6 +4682,10 @@ static int lfs_fs_demove(lfs_t *lfs) {
lfs->gdisk.pair[1],
lfs_tag_id(lfs->gdisk.tag));
// no other gstate is supported at this time, so if we found something else
// something most likely went wrong in gstate calculation
LFS_ASSERT(lfs_tag_type3(lfs->gdisk.tag) == LFS_TYPE_DELETE);
// fetch and delete the moved entry
lfs_mdir_t movedir;
int err = lfs_dir_fetch(lfs, &movedir, lfs->gdisk.pair);
@@ -4483,11 +4713,21 @@ static int lfs_fs_deorphan(lfs_t *lfs, bool powerloss) {
}
int8_t found = 0;
restart:
{
// Check for orphans in two separate passes:
// - 1 for half-orphans (relocations)
// - 2 for full-orphans (removes/renames)
//
// Two separate passes are needed as half-orphans can contain outdated
// references to full-orphans, effectively hiding them from the deorphan
// search.
//
int pass = 0;
while (pass < 2) {
// Fix any orphans
lfs_mdir_t pdir = {.split = true, .tail = {0, 1}};
lfs_mdir_t dir;
bool moreorphans = false;
// iterate over all directory directory entries
while (!lfs_pair_isnull(pdir.tail)) {
@@ -4505,42 +4745,7 @@ restart:
return tag;
}
// note we only check for full orphans if we may have had a
// power-loss, otherwise orphans are created intentionally
// during operations such as lfs_mkdir
if (tag == LFS_ERR_NOENT && powerloss) {
// we are an orphan
LFS_DEBUG("Fixing orphan {0x%"PRIx32", 0x%"PRIx32"}",
pdir.tail[0], pdir.tail[1]);
// steal state
err = lfs_dir_getgstate(lfs, &dir, &lfs->gdelta);
if (err) {
return err;
}
// steal tail
lfs_pair_tole32(dir.tail);
int state = lfs_dir_orphaningcommit(lfs, &pdir, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_TAIL + dir.split, 0x3ff, 8),
dir.tail}));
lfs_pair_fromle32(dir.tail);
if (state < 0) {
return state;
}
found += 1;
// did our commit create more orphans?
if (state == LFS_OK_ORPHANED) {
goto restart;
}
// refetch tail
continue;
}
if (tag != LFS_ERR_NOENT) {
if (pass == 0 && tag != LFS_ERR_NOENT) {
lfs_block_t pair[2];
lfs_stag_t state = lfs_dir_get(lfs, &parent,
LFS_MKTAG(0x7ff, 0x3ff, 0), tag, pair);
@@ -4549,7 +4754,7 @@ restart:
}
lfs_pair_fromle32(pair);
if (!lfs_pair_sync(pair, pdir.tail)) {
if (!lfs_pair_issync(pair, pdir.tail)) {
// we have desynced
LFS_DEBUG("Fixing half-orphan "
"{0x%"PRIx32", 0x%"PRIx32"} "
@@ -4583,17 +4788,54 @@ restart:
// did our commit create more orphans?
if (state == LFS_OK_ORPHANED) {
goto restart;
moreorphans = true;
}
// refetch tail
continue;
}
}
// note we only check for full orphans if we may have had a
// power-loss, otherwise orphans are created intentionally
// during operations such as lfs_mkdir
if (pass == 1 && tag == LFS_ERR_NOENT && powerloss) {
// we are an orphan
LFS_DEBUG("Fixing orphan {0x%"PRIx32", 0x%"PRIx32"}",
pdir.tail[0], pdir.tail[1]);
// steal state
err = lfs_dir_getgstate(lfs, &dir, &lfs->gdelta);
if (err) {
return err;
}
// steal tail
lfs_pair_tole32(dir.tail);
int state = lfs_dir_orphaningcommit(lfs, &pdir, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_TAIL + dir.split, 0x3ff, 8),
dir.tail}));
lfs_pair_fromle32(dir.tail);
if (state < 0) {
return state;
}
found += 1;
// did our commit create more orphans?
if (state == LFS_OK_ORPHANED) {
moreorphans = true;
}
// refetch tail
continue;
}
}
pdir = dir;
}
pass = moreorphans ? 0 : pass+1;
}
// mark orphans as fixed
@@ -4605,7 +4847,12 @@ restart:
#ifndef LFS_READONLY
static int lfs_fs_forceconsistency(lfs_t *lfs) {
int err = lfs_fs_demove(lfs);
int err = lfs_fs_desuperblock(lfs);
if (err) {
return err;
}
err = lfs_fs_demove(lfs);
if (err) {
return err;
}