From a0a55fb9e5942b51331947b855756abcac42a3c5 Mon Sep 17 00:00:00 2001 From: Christopher Haster Date: Fri, 2 Feb 2018 05:58:43 -0600 Subject: [PATCH] Added conversion to/from little-endian on disk Required to support big-endian processors, with the most notable being the PowerPC architecture. On little-endian architectures, these conversions can be optimized out and have no code impact. Initial patch provided by gmouchard --- lfs.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++---- lfs_util.h | 23 +++++++++++++++ 2 files changed, 99 insertions(+), 6 deletions(-) diff --git a/lfs.c b/lfs.c index b7cc6755792..0374853fa4d 100644 --- a/lfs.c +++ b/lfs.c @@ -323,6 +323,48 @@ static void lfs_alloc_ack(lfs_t *lfs) { } +/// Endian swapping functions /// +static void lfs_dir_fromle32(struct lfs_disk_dir *d) { + d->rev = lfs_fromle32(d->rev); + d->size = lfs_fromle32(d->size); + d->tail[0] = lfs_fromle32(d->tail[0]); + d->tail[1] = lfs_fromle32(d->tail[1]); +} + +static void lfs_dir_tole32(struct lfs_disk_dir *d) { + d->rev = lfs_tole32(d->rev); + d->size = lfs_tole32(d->size); + d->tail[0] = lfs_tole32(d->tail[0]); + d->tail[1] = lfs_tole32(d->tail[1]); +} + +static void lfs_entry_fromle32(struct lfs_disk_entry *d) { + d->u.dir[0] = lfs_fromle32(d->u.dir[0]); + d->u.dir[1] = lfs_fromle32(d->u.dir[1]); +} + +static void lfs_entry_tole32(struct lfs_disk_entry *d) { + d->u.dir[0] = lfs_tole32(d->u.dir[0]); + d->u.dir[1] = lfs_tole32(d->u.dir[1]); +} + +static void lfs_superblock_fromle32(struct lfs_disk_superblock *d) { + d->root[0] = lfs_fromle32(d->root[0]); + d->root[1] = lfs_fromle32(d->root[1]); + d->block_size = lfs_fromle32(d->block_size); + d->block_count = lfs_fromle32(d->block_count); + d->version = lfs_fromle32(d->version); +} + +static void lfs_superblock_tole32(struct lfs_disk_superblock *d) { + d->root[0] = lfs_tole32(d->root[0]); + d->root[1] = lfs_tole32(d->root[1]); + d->block_size = lfs_tole32(d->block_size); + d->block_count = lfs_tole32(d->block_count); + d->version = lfs_tole32(d->version); +} + + /// Metadata pair and directory operations /// static inline void lfs_pairswap(lfs_block_t pair[2]) { lfs_block_t t = pair[0]; @@ -364,6 +406,7 @@ static int lfs_dir_alloc(lfs_t *lfs, lfs_dir_t *dir) { // rather than clobbering one of the blocks we just pretend // the revision may be valid int err = lfs_bd_read(lfs, dir->pair[0], 0, &dir->d.rev, 4); + dir->d.rev = lfs_fromle32(dir->d.rev); if (err) { return err; } @@ -389,6 +432,7 @@ static int lfs_dir_fetch(lfs_t *lfs, for (int i = 0; i < 2; i++) { struct lfs_disk_dir test; int err = lfs_bd_read(lfs, tpair[i], 0, &test, sizeof(test)); + lfs_dir_fromle32(&test); if (err) { return err; } @@ -403,7 +447,9 @@ static int lfs_dir_fetch(lfs_t *lfs, } uint32_t crc = 0xffffffff; + lfs_dir_tole32(&test); lfs_crc(&crc, &test, sizeof(test)); + lfs_dir_fromle32(&test); err = lfs_bd_crc(lfs, tpair[i], sizeof(test), (0x7fffffff & test.size) - sizeof(test), &crc); if (err) { @@ -463,8 +509,10 @@ static int lfs_dir_commit(lfs_t *lfs, lfs_dir_t *dir, } uint32_t crc = 0xffffffff; + lfs_dir_tole32(&dir->d); lfs_crc(&crc, &dir->d, sizeof(dir->d)); err = lfs_bd_prog(lfs, dir->pair[0], 0, &dir->d, sizeof(dir->d)); + lfs_dir_fromle32(&dir->d); if (err) { if (err == LFS_ERR_CORRUPT) { goto relocate; @@ -511,7 +559,9 @@ static int lfs_dir_commit(lfs_t *lfs, lfs_dir_t *dir, } } + crc = lfs_tole32(crc); err = lfs_bd_prog(lfs, dir->pair[0], newoff, &crc, 4); + crc = lfs_fromle32(crc); if (err) { if (err == LFS_ERR_CORRUPT) { goto relocate; @@ -584,11 +634,14 @@ static int lfs_dir_commit(lfs_t *lfs, lfs_dir_t *dir, } static int lfs_dir_update(lfs_t *lfs, lfs_dir_t *dir, - const lfs_entry_t *entry, const void *data) { - return lfs_dir_commit(lfs, dir, (struct lfs_region[]){ + lfs_entry_t *entry, const void *data) { + lfs_entry_tole32(&entry->d); + int err = lfs_dir_commit(lfs, dir, (struct lfs_region[]){ {entry->off, sizeof(entry->d), &entry->d, sizeof(entry->d)}, {entry->off+sizeof(entry->d), entry->d.nlen, data, entry->d.nlen} }, data ? 2 : 1); + lfs_entry_fromle32(&entry->d); + return err; } static int lfs_dir_append(lfs_t *lfs, lfs_dir_t *dir, @@ -597,10 +650,14 @@ static int lfs_dir_append(lfs_t *lfs, lfs_dir_t *dir, while (true) { if (dir->d.size + lfs_entry_size(entry) <= lfs->cfg->block_size) { entry->off = dir->d.size - 4; - return lfs_dir_commit(lfs, dir, (struct lfs_region[]){ + + lfs_entry_tole32(&entry->d); + int err = lfs_dir_commit(lfs, dir, (struct lfs_region[]){ {entry->off, 0, &entry->d, sizeof(entry->d)}, {entry->off, 0, data, entry->d.nlen} }, 2); + lfs_entry_fromle32(&entry->d); + return err; } // we need to allocate a new dir block @@ -614,10 +671,12 @@ static int lfs_dir_append(lfs_t *lfs, lfs_dir_t *dir, newdir.d.tail[0] = dir->d.tail[0]; newdir.d.tail[1] = dir->d.tail[1]; entry->off = newdir.d.size - 4; + lfs_entry_tole32(&entry->d); err = lfs_dir_commit(lfs, &newdir, (struct lfs_region[]){ {entry->off, 0, &entry->d, sizeof(entry->d)}, {entry->off, 0, data, entry->d.nlen} }, 2); + lfs_entry_fromle32(&entry->d); if (err) { return err; } @@ -703,6 +762,7 @@ static int lfs_dir_next(lfs_t *lfs, lfs_dir_t *dir, lfs_entry_t *entry) { int err = lfs_bd_read(lfs, dir->pair[0], dir->off, &entry->d, sizeof(entry->d)); + lfs_entry_fromle32(&entry->d); if (err) { return err; } @@ -1065,6 +1125,7 @@ static int lfs_ctz_find(lfs_t *lfs, lfs_ctz(current)); int err = lfs_cache_read(lfs, rcache, pcache, head, 4*skip, &head, 4); + head = lfs_fromle32(head); if (err) { return err; } @@ -1140,8 +1201,10 @@ static int lfs_ctz_extend(lfs_t *lfs, lfs_size_t skips = lfs_ctz(index) + 1; for (lfs_off_t i = 0; i < skips; i++) { + head = lfs_tole32(head); err = lfs_cache_prog(lfs, pcache, rcache, nblock, 4*i, &head, 4); + head = lfs_fromle32(head); if (err) { if (err == LFS_ERR_CORRUPT) { goto relocate; @@ -1152,6 +1215,7 @@ static int lfs_ctz_extend(lfs_t *lfs, if (i != skips-1) { err = lfs_cache_read(lfs, rcache, NULL, head, 4*i, &head, 4); + head = lfs_fromle32(head); if (err) { return err; } @@ -1196,6 +1260,8 @@ static int lfs_ctz_traverse(lfs_t *lfs, lfs_block_t heads[2]; int count = 2 - (index & 1); err = lfs_cache_read(lfs, rcache, pcache, head, 0, &heads, count*4); + heads[0] = lfs_fromle32(heads[0]); + heads[1] = lfs_fromle32(heads[1]); if (err) { return err; } @@ -1456,6 +1522,7 @@ int lfs_file_sync(lfs_t *lfs, lfs_file_t *file) { lfs_entry_t entry = {.off = file->poff}; err = lfs_bd_read(lfs, cwd.pair[0], entry.off, &entry.d, sizeof(entry.d)); + lfs_entry_fromle32(&entry.d); if (err) { return err; } @@ -2075,6 +2142,7 @@ int lfs_format(lfs_t *lfs, const struct lfs_config *cfg) { superdir.d.size = sizeof(superdir.d) + sizeof(superblock.d) + 4; // write both pairs to be safe + lfs_superblock_tole32(&superblock.d); bool valid = false; for (int i = 0; i < 2; i++) { err = lfs_dir_commit(lfs, &superdir, (struct lfs_region[]){ @@ -2125,6 +2193,7 @@ int lfs_mount(lfs_t *lfs, const struct lfs_config *cfg) { if (!err) { err = lfs_bd_read(lfs, dir.pair[0], sizeof(dir.d), &superblock.d, sizeof(superblock.d)); + lfs_superblock_fromle32(&superblock.d); if (err) { return err; } @@ -2182,6 +2251,7 @@ int lfs_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data) { while (dir.off + sizeof(entry.d) <= (0x7fffffff & dir.d.size)-4) { err = lfs_bd_read(lfs, dir.pair[0], dir.off, &entry.d, sizeof(entry.d)); + lfs_entry_fromle32(&entry.d); if (err) { return err; } @@ -2222,7 +2292,7 @@ int lfs_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data) { } } } - + return 0; } @@ -2256,7 +2326,7 @@ static int lfs_parent(lfs_t *lfs, const lfs_block_t dir[2], if (lfs_pairisnull(lfs->root)) { return 0; } - + parent->d.tail[0] = 0; parent->d.tail[1] = 1; @@ -2317,7 +2387,7 @@ static int lfs_moved(lfs_t *lfs, const void *e) { break; } - if (!(0x80 & entry.d.type) && + if (!(0x80 & entry.d.type) && memcmp(&entry.d.u, e, sizeof(entry.d.u)) == 0) { return true; } diff --git a/lfs_util.h b/lfs_util.h index 586a32e33ad..9fe77de3025 100644 --- a/lfs_util.h +++ b/lfs_util.h @@ -70,6 +70,29 @@ static inline int lfs_scmp(uint32_t a, uint32_t b) { return (int)(unsigned)(a - b); } +static inline uint32_t lfs_fromle32(uint32_t a) { +#if ( \ + (defined( BYTE_ORDER ) && BYTE_ORDER == ORDER_LITTLE_ENDIAN ) || \ + (defined(__BYTE_ORDER ) && __BYTE_ORDER == __ORDER_LITTLE_ENDIAN ) || \ + (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)) + return a; +#elif ( \ + (defined( BYTE_ORDER ) && BYTE_ORDER == ORDER_BIG_ENDIAN ) || \ + (defined(__BYTE_ORDER ) && __BYTE_ORDER == __ORDER_BIG_ENDIAN ) || \ + (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)) + return __builtin_bswap32(a); +#else + return (((uint8_t*)&a)[0] << 0) | + (((uint8_t*)&a)[1] << 8) | + (((uint8_t*)&a)[2] << 16) | + (((uint8_t*)&a)[3] << 24); +#endif +} + +static inline uint32_t lfs_tole32(uint32_t a) { + return lfs_fromle32(a); +} + // CRC-32 with polynomial = 0x04c11db7 void lfs_crc(uint32_t *crc, const void *buffer, size_t size);