diff --git a/lfs.c b/lfs.c index af3a5d7..a8724bb 100644 --- a/lfs.c +++ b/lfs.c @@ -1232,65 +1232,85 @@ static int lfs_dir_commitattr(lfs_t *lfs, struct lfs_commit *commit, static int lfs_dir_commitcrc(lfs_t *lfs, struct lfs_commit *commit) { // align to program units - lfs_off_t off = lfs_alignup(commit->off + 2*sizeof(uint32_t), + const lfs_off_t off1 = commit->off + sizeof(lfs_tag_t); + const lfs_off_t end = lfs_alignup(off1 + sizeof(uint32_t), lfs->cfg->prog_size); - // read erased state from next program unit - lfs_tag_t tag; - int err = lfs_bd_read(lfs, - NULL, &lfs->rcache, sizeof(tag), - commit->block, off, &tag, sizeof(tag)); - if (err && err != LFS_ERR_CORRUPT) { - return err; - } + // create crc tags to fill up remainder of commit, note that + // padding is not crcd, 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; + if (noff < end) { + noff = lfs_min(noff, end - 2*sizeof(uint32_t)); + } - // build crc tag - bool reset = ~lfs_frombe32(tag) >> 31; - tag = LFS_MKTAG(LFS_TYPE_CRC + reset, 0x3ff, - lfs_min(off - (commit->off+sizeof(lfs_tag_t)), 0x3fe)); + // 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; + } - // 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, - &lfs->pcache, &lfs->rcache, false, - commit->block, commit->off, &footer, sizeof(footer)); - if (err) { - return err; - } - commit->off += sizeof(tag)+lfs_tag_size(tag); - commit->ptag = tag ^ (reset << 31); + // build crc tag + bool reset = ~lfs_frombe32(tag) >> 31; + tag = LFS_MKTAG(LFS_TYPE_CRC + reset, 0x3ff, noff - off); - // flush buffers - err = lfs_bd_sync(lfs, &lfs->pcache, &lfs->rcache, false); - if (err) { - return err; - } - - // successful commit, check checksum to make sure - uint32_t crc = 0xffffffff; - lfs_size_t size = commit->off - lfs_tag_size(tag) - commit->begin; - for (lfs_off_t i = 0; i < size; i++) { - // leave it up to caching to make this efficient - uint8_t dat; - err = lfs_bd_read(lfs, - NULL, &lfs->rcache, size-i, - commit->block, commit->begin+i, &dat, 1); + // 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, + &lfs->pcache, &lfs->rcache, false, + commit->block, commit->off, &footer, sizeof(footer)); if (err) { return err; } - crc = lfs_crc(crc, &dat, 1); + commit->off += sizeof(tag)+lfs_tag_size(tag); + commit->ptag = tag ^ (reset << 31); + commit->crc = 0xffffffff; // reset crc for next "commit" } + // flush buffers + int err = lfs_bd_sync(lfs, &lfs->pcache, &lfs->rcache, false); if (err) { return err; } - if (crc != commit->crc) { - return LFS_ERR_CORRUPT; + // 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++) { + // 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; + } + + 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); } return 0; @@ -1583,11 +1603,11 @@ static int lfs_dir_compact(lfs_t *lfs, } // successful compaction, swap dir pair to indicate most recent + LFS_ASSERT(commit.off % lfs->cfg->prog_size == 0); lfs_pair_swap(dir->pair); dir->count = end - begin; dir->off = commit.off; dir->etag = commit.ptag; - dir->erased = (dir->off % lfs->cfg->prog_size == 0); // note we able to have already handled move here if (lfs_gstate_hasmovehere(&lfs->gpending, dir->pair)) { lfs_gstate_xormove(&lfs->gpending, @@ -1758,10 +1778,9 @@ static int lfs_dir_commit(lfs_t *lfs, lfs_mdir_t *dir, } // successful commit, update dir + LFS_ASSERT(commit.off % lfs->cfg->prog_size == 0); dir->off = commit.off; dir->etag = commit.ptag; - // workaround to handle prog_size >1024 - dir->erased = (dir->off % lfs->cfg->prog_size == 0); // note we able to have already handled move here if (lfs_gstate_hasmovehere(&lfs->gpending, dir->pair)) {