static int
nffs_gc_block_chain_copy(struct nffs_hash_entry *last_entry, uint32_t data_len,
uint8_t to_area_idx)
{
struct nffs_hash_entry *entry;
struct nffs_block block;
uint32_t data_bytes_copied;
uint16_t copy_len;
int rc;
data_bytes_copied = 0;
entry = last_entry;
while (data_bytes_copied < data_len) {
assert(entry != NULL);
rc = nffs_block_from_hash_entry(&block, entry);
if (rc != 0) {
return rc;
}
copy_len = sizeof (struct nffs_disk_block) + block.nb_data_len;
rc = nffs_gc_copy_object(entry, copy_len, to_area_idx);
if (rc != 0) {
return rc;
}
data_bytes_copied += block.nb_data_len;
entry = block.nb_prev;
}
return 0;
}
/**
* Checks that each block a chain of data blocks was properly restored.
*
* @param last_block_entry The entry corresponding to the last block in
* the chain.
*
* @return 0 if the block chain is OK;
* FS_ECORRUPT if corruption is detected;
* nonzero on other error.
*/
static int
nffs_restore_validate_block_chain(struct nffs_hash_entry *last_block_entry)
{
struct nffs_disk_block disk_block;
struct nffs_hash_entry *cur;
struct nffs_block block;
uint32_t area_offset;
uint8_t area_idx;
int rc;
cur = last_block_entry;
while (cur != NULL) {
nffs_flash_loc_expand(cur->nhe_flash_loc, &area_idx, &area_offset);
rc = nffs_block_read_disk(area_idx, area_offset, &disk_block);
if (rc != 0) {
return rc;
}
rc = nffs_block_from_hash_entry(&block, cur);
if (rc != 0) {
return rc;
}
cur = block.nb_prev;
}
return 0;
}
/**
* Deletes the specified block entry from the nffs RAM representation.
*
* @param block_entry The block entry to delete.
*
* @return 0 on success; nonzero on failure.
*/
int
nffs_block_delete_from_ram(struct nffs_hash_entry *block_entry)
{
struct nffs_block block;
int rc;
rc = nffs_block_from_hash_entry(&block, block_entry);
if (rc != 0) {
return rc;
}
assert(block.nb_inode_entry != NULL);
if (block.nb_inode_entry->nie_last_block_entry == block_entry) {
block.nb_inode_entry->nie_last_block_entry = block.nb_prev;
}
nffs_hash_remove(block_entry);
nffs_block_entry_free(block_entry);
return 0;
}
/**
* Deletes the specified block entry from the nffs RAM representation.
*
* @param block_entry The block entry to delete.
*
* @return 0 on success; nonzero on failure.
*/
int
nffs_block_delete_from_ram(struct nffs_hash_entry *block_entry)
{
struct nffs_inode_entry *inode_entry;
struct nffs_block block;
int rc;
if (nffs_hash_entry_is_dummy(block_entry)) {
/*
* it's very limited to what we can do here as the block doesn't have
* any way to get to the inode via hash entry. Just delete the
* block and return FS_ECORRUPT
*/
nffs_hash_remove(block_entry);
nffs_block_entry_free(block_entry);
return FS_ECORRUPT;
}
rc = nffs_block_from_hash_entry(&block, block_entry);
if (rc == 0 || rc == FS_ECORRUPT) {
/* If file system corruption was detected, the resulting block is still
* valid and can be removed from RAM.
* Note that FS_CORRUPT can occur because the owning inode was not
* found in the hash table - this can occur during the sweep where
* the inodes were deleted ahead of the blocks.
*/
inode_entry = block.nb_inode_entry;
if (inode_entry != NULL &&
inode_entry->nie_last_block_entry == block_entry) {
inode_entry->nie_last_block_entry = block.nb_prev;
}
nffs_hash_remove(block_entry);
nffs_block_entry_free(block_entry);
}
return rc;
}
static int
nffs_gc_inode_blocks(struct nffs_inode_entry *inode_entry,
uint8_t from_area_idx, uint8_t to_area_idx,
struct nffs_hash_entry **inout_next)
{
struct nffs_hash_entry *last_entry;
struct nffs_hash_entry *entry;
struct nffs_block block;
uint32_t prospective_data_len;
uint32_t area_offset;
uint32_t data_len;
uint8_t area_idx;
int multiple_blocks;
int rc;
assert(nffs_hash_id_is_file(inode_entry->nie_hash_entry.nhe_id));
data_len = 0;
last_entry = NULL;
multiple_blocks = 0;
entry = inode_entry->nie_last_block_entry;
while (entry != NULL) {
rc = nffs_block_from_hash_entry(&block, entry);
if (rc != 0) {
return rc;
}
nffs_flash_loc_expand(entry->nhe_flash_loc, &area_idx, &area_offset);
if (area_idx == from_area_idx) {
if (last_entry == NULL) {
last_entry = entry;
}
prospective_data_len = data_len + block.nb_data_len;
if (prospective_data_len <= nffs_block_max_data_sz) {
data_len = prospective_data_len;
if (last_entry != entry) {
multiple_blocks = 1;
}
} else {
rc = nffs_gc_block_chain(last_entry, multiple_blocks, data_len,
to_area_idx, inout_next);
if (rc != 0) {
return rc;
}
last_entry = entry;
data_len = block.nb_data_len;
multiple_blocks = 0;
}
} else {
if (last_entry != NULL) {
rc = nffs_gc_block_chain(last_entry, multiple_blocks, data_len,
to_area_idx, inout_next);
if (rc != 0) {
return rc;
}
last_entry = NULL;
data_len = 0;
multiple_blocks = 0;
}
}
entry = block.nb_prev;
}
if (last_entry != NULL) {
rc = nffs_gc_block_chain(last_entry, multiple_blocks, data_len,
to_area_idx, inout_next);
if (rc != 0) {
return rc;
}
}
return 0;
}
/**
* Moves a chain of blocks from one area to another. This function attempts to
* collate the blocks into a single new block in the destination area.
*
* @param last_entry The last block entry in the chain.
* @param data_len The total length of data to collate.
* @param to_area_idx The index of the area to copy to.
* @param inout_next This parameter is only necessary if you are
* calling this function during an iteration
* of the entire hash table; pass null
* otherwise.
* On input, this points to the next hash entry
* you plan on processing.
* On output, this points to the next hash entry
* that should be processed.
*
* @return 0 on success;
* FS_ENOMEM if there is insufficient heap;
* other nonzero on failure.
*/
static int
nffs_gc_block_chain_collate(struct nffs_hash_entry *last_entry,
uint32_t data_len, uint8_t to_area_idx,
struct nffs_hash_entry **inout_next)
{
struct nffs_disk_block disk_block;
struct nffs_hash_entry *entry;
struct nffs_area *to_area;
struct nffs_block last_block;
struct nffs_block block;
uint32_t to_area_offset;
uint32_t from_area_offset;
uint32_t data_offset;
uint8_t *data;
uint8_t from_area_idx;
int rc;
memset(&last_block, 0, sizeof last_block);
data = malloc(data_len);
if (data == NULL) {
rc = FS_ENOMEM;
goto done;
}
memset(&last_block, 0, sizeof(last_block));
to_area = nffs_areas + to_area_idx;
entry = last_entry;
data_offset = data_len;
while (data_offset > 0) {
rc = nffs_block_from_hash_entry(&block, entry);
if (rc != 0) {
goto done;
}
data_offset -= block.nb_data_len;
nffs_flash_loc_expand(block.nb_hash_entry->nhe_flash_loc,
&from_area_idx, &from_area_offset);
from_area_offset += sizeof disk_block;
STATS_INC(nffs_stats, nffs_readcnt_gccollate);
rc = nffs_flash_read(from_area_idx, from_area_offset,
data + data_offset, block.nb_data_len);
if (rc != 0) {
goto done;
}
if (entry != last_entry) {
if (inout_next != NULL && *inout_next == entry) {
*inout_next = SLIST_NEXT(entry, nhe_next);
}
nffs_block_delete_from_ram(entry);
} else {
last_block = block;
}
entry = block.nb_prev;
}
/* we had better have found the last block */
assert(last_block.nb_hash_entry);
/* The resulting block should inherit its ID from its last constituent
* block (this is the ID referenced by the parent inode and subsequent data
* block). The previous ID gets inherited from the first constituent
* block.
*/
memset(&disk_block, 0, sizeof disk_block);
disk_block.ndb_id = last_block.nb_hash_entry->nhe_id;
disk_block.ndb_seq = last_block.nb_seq + 1;
disk_block.ndb_inode_id = last_block.nb_inode_entry->nie_hash_entry.nhe_id;
if (entry == NULL) {
disk_block.ndb_prev_id = NFFS_ID_NONE;
} else {
disk_block.ndb_prev_id = entry->nhe_id;
}
disk_block.ndb_data_len = data_len;
nffs_crc_disk_block_fill(&disk_block, data);
to_area_offset = to_area->na_cur;
rc = nffs_flash_write(to_area_idx, to_area_offset,
&disk_block, sizeof disk_block);
if (rc != 0) {
goto done;
}
rc = nffs_flash_write(to_area_idx, to_area_offset + sizeof disk_block,
data, data_len);
if (rc != 0) {
goto done;
}
last_entry->nhe_flash_loc = nffs_flash_loc(to_area_idx, to_area_offset);
rc = 0;
ASSERT_IF_TEST(nffs_crc_disk_block_validate(&disk_block, to_area_idx,
to_area_offset) == 0);
done:
free(data);
return rc;
}
/**
* Moves a chain of blocks from one area to another. This function attempts to
* collate the blocks into a single new block in the destination area.
*
* @param last_entry The last block entry in the chain.
* @param data_len The total length of data to collate.
* @param to_area_idx The index of the area to copy to.
* @param inout_next This parameter is only necessary if you are
* calling this function during an iteration
* of the entire hash table; pass null
* otherwise.
* On input, this points to the next hash entry
* you plan on processing.
* On output, this points to the next hash entry
* that should be processed.
*
* @return 0 on success;
* FS_ENOMEM if there is insufficient heap;
* other nonzero on failure.
*/
static int
nffs_gc_block_chain_collate(struct nffs_hash_entry *last_entry,
uint32_t data_len, uint8_t to_area_idx,
struct nffs_hash_entry **inout_next)
{
struct nffs_disk_block disk_block;
struct nffs_hash_entry *entry;
struct nffs_area *to_area;
struct nffs_block block;
uint32_t to_area_offset;
uint32_t from_area_offset;
uint32_t data_offset;
uint8_t *data;
uint8_t from_area_idx;
int rc;
data = malloc(data_len);
if (data == NULL) {
rc = FS_ENOMEM;
goto done;
}
to_area = nffs_areas + to_area_idx;
entry = last_entry;
data_offset = data_len;
while (data_offset > 0) {
rc = nffs_block_from_hash_entry(&block, entry);
if (rc != 0) {
goto done;
}
data_offset -= block.nb_data_len;
nffs_flash_loc_expand(block.nb_hash_entry->nhe_flash_loc,
&from_area_idx, &from_area_offset);
from_area_offset += sizeof disk_block;
rc = nffs_flash_read(from_area_idx, from_area_offset,
data + data_offset, block.nb_data_len);
if (rc != 0) {
goto done;
}
if (entry != last_entry) {
if (inout_next != NULL && *inout_next == entry) {
*inout_next = SLIST_NEXT(entry, nhe_next);
}
nffs_block_delete_from_ram(entry);
}
entry = block.nb_prev;
}
memset(&disk_block, 0, sizeof disk_block);
disk_block.ndb_magic = NFFS_BLOCK_MAGIC;
disk_block.ndb_id = block.nb_hash_entry->nhe_id;
disk_block.ndb_seq = block.nb_seq + 1;
disk_block.ndb_inode_id = block.nb_inode_entry->nie_hash_entry.nhe_id;
if (entry == NULL) {
disk_block.ndb_prev_id = NFFS_ID_NONE;
} else {
disk_block.ndb_prev_id = entry->nhe_id;
}
disk_block.ndb_data_len = data_len;
nffs_crc_disk_block_fill(&disk_block, data);
to_area_offset = to_area->na_cur;
rc = nffs_flash_write(to_area_idx, to_area_offset,
&disk_block, sizeof disk_block);
if (rc != 0) {
goto done;
}
rc = nffs_flash_write(to_area_idx, to_area_offset + sizeof disk_block,
data, data_len);
if (rc != 0) {
goto done;
}
last_entry->nhe_flash_loc = nffs_flash_loc(to_area_idx, to_area_offset);
rc = 0;
ASSERT_IF_TEST(nffs_crc_disk_block_validate(&disk_block, to_area_idx,
to_area_offset) == 0);
done:
free(data);
return rc;
}
/**
* Overwrites an existing data block. The resulting block has the same ID as
* the old one, but it supersedes it with a greater sequence number.
*
* @param entry The data block to overwrite.
* @param left_copy_len The number of bytes of existing data to retain
* before the new data begins.
* @param new_data The new data to write to the block.
* @param new_data_len The number of new bytes to write to the block.
* If this value plus left_copy_len is less
* than the existing block's data length,
* previous data at the end of the block is
* retained.
*
* @return 0 on success; nonzero on failure.
*/
static int
nffs_write_over_block(struct nffs_hash_entry *entry, uint16_t left_copy_len,
const void *new_data, uint16_t new_data_len)
{
struct nffs_disk_block disk_block;
struct nffs_block block;
uint32_t src_area_offset;
uint32_t dst_area_offset;
uint16_t right_copy_len;
uint16_t block_off;
uint8_t src_area_idx;
uint8_t dst_area_idx;
int rc;
rc = nffs_block_from_hash_entry(&block, entry);
if (rc != 0) {
return rc;
}
assert(left_copy_len <= block.nb_data_len);
/* Determine how much old data at the end of the block needs to be
* retained. If the new data doesn't extend to the end of the block, the
* the rest of the block retains its old contents.
*/
if (left_copy_len + new_data_len > block.nb_data_len) {
right_copy_len = 0;
} else {
right_copy_len = block.nb_data_len - left_copy_len - new_data_len;
}
block.nb_seq++;
block.nb_data_len = left_copy_len + new_data_len + right_copy_len;
nffs_block_to_disk(&block, &disk_block);
nffs_flash_loc_expand(entry->nhe_flash_loc,
&src_area_idx, &src_area_offset);
rc = nffs_write_fill_crc16_overwrite(&disk_block,
src_area_idx, src_area_offset,
left_copy_len, right_copy_len,
new_data, new_data_len);
if (rc != 0) {
return rc;
}
rc = nffs_misc_reserve_space(sizeof disk_block + disk_block.ndb_data_len,
&dst_area_idx, &dst_area_offset);
if (rc != 0) {
return rc;
}
block_off = 0;
/* Write the block header. */
rc = nffs_flash_write(dst_area_idx, dst_area_offset + block_off,
&disk_block, sizeof disk_block);
if (rc != 0) {
return rc;
}
block_off += sizeof disk_block;
/* Copy data from the start of the old block, in case the new data starts
* at a non-zero offset.
*/
if (left_copy_len > 0) {
rc = nffs_flash_copy(src_area_idx, src_area_offset + block_off,
dst_area_idx, dst_area_offset + block_off,
left_copy_len);
if (rc != 0) {
return rc;
}
block_off += left_copy_len;
}
/* Write the new data into the data block. This may extend the block's
* length beyond its old value.
*/
rc = nffs_flash_write(dst_area_idx, dst_area_offset + block_off,
new_data, new_data_len);
if (rc != 0) {
return rc;
}
block_off += new_data_len;
/* Copy data from the end of the old block, in case the new data doesn't
* extend to the end of the block.
*/
if (right_copy_len > 0) {
rc = nffs_flash_copy(src_area_idx, src_area_offset + block_off,
dst_area_idx, dst_area_offset + block_off,
right_copy_len);
if (rc != 0) {
return rc;
}
block_off += right_copy_len;
}
assert(block_off == sizeof disk_block + block.nb_data_len);
entry->nhe_flash_loc = nffs_flash_loc(dst_area_idx, dst_area_offset);
ASSERT_IF_TEST(nffs_crc_disk_block_validate(&disk_block, dst_area_idx,
dst_area_offset) == 0);
return 0;
}
/**
* Performs a sweep of the RAM representation at the end of a successful
* restore. The sweep phase performs the following actions of each inode in
* the file system:
* 1. If the inode is a dummy directory, its children are migrated to the
* lost+found directory.
* 2. Else if the inode is a dummy file, it is fully deleted from RAM.
* 3. Else, a CRC check is performed on each of the inode's constituent
* blocks. If corruption is detected, the inode is fully deleted from
* RAM.
*
* @return 0 on success; nonzero on failure.
*/
int
nffs_restore_sweep(void)
{
struct nffs_inode_entry *inode_entry;
struct nffs_hash_entry *entry;
struct nffs_hash_entry *next;
struct nffs_hash_list *list;
struct nffs_inode inode;
struct nffs_block block;
int del = 0;
int rc;
int i;
/* Iterate through every object in the hash table, deleting all inodes that
* should be removed.
*/
for (i = 0; i < NFFS_HASH_SIZE; i++) {
list = nffs_hash + i;
entry = SLIST_FIRST(list);
while (entry != NULL) {
next = SLIST_NEXT(entry, nhe_next);
if (nffs_hash_id_is_inode(entry->nhe_id)) {
inode_entry = (struct nffs_inode_entry *)entry;
/*
* If this is a dummy inode directory, the file system
* is corrupt. Move the directory's children inodes to
* the lost+found directory.
*/
rc = nffs_restore_migrate_orphan_children(inode_entry);
if (rc != 0) {
return rc;
}
/* Determine if this inode needs to be deleted. */
rc = nffs_restore_should_sweep_inode_entry(inode_entry, &del);
if (rc != 0) {
return rc;
}
rc = nffs_inode_from_entry(&inode, inode_entry);
if (rc != 0 && rc != FS_ENOENT) {
return rc;
}
if (del) {
/* Remove the inode and all its children from RAM. We
* expect some file system corruption; the children are
* subject to garbage collection and may not exist in the
* hash. Remove what is actually present and ignore
* corruption errors.
*/
rc = nffs_inode_unlink_from_ram_corrupt_ok(&inode, &next);
if (rc != 0) {
return rc;
}
next = SLIST_FIRST(list);
}
} else if (nffs_hash_id_is_block(entry->nhe_id)) {
if (nffs_hash_id_is_dummy(entry->nhe_id)) {
del = 1;
nffs_block_delete_from_ram(entry);
} else {
rc = nffs_block_from_hash_entry(&block, entry);
if (rc != 0 && rc != FS_ENOENT) {
del = 1;
nffs_block_delete_from_ram(entry);
}
}
if (del) {
del = 0;
next = SLIST_FIRST(list);
}
}
entry = next;
}
}
return 0;
}
static void
nffs_log_contents(void)
{
#if MYNEWT_VAL(LOG_LEVEL) > LOG_LEVEL_DEBUG
return;
#endif
struct nffs_inode_entry *inode_entry;
struct nffs_hash_entry *entry;
struct nffs_hash_entry *next;
struct nffs_block block;
struct nffs_inode inode;
int rc;
int i;
NFFS_HASH_FOREACH(entry, i, next) {
if (nffs_hash_id_is_block(entry->nhe_id)) {
rc = nffs_block_from_hash_entry(&block, entry);
assert(rc == 0 || rc == FS_ENOENT);
NFFS_LOG(DEBUG, "block; id=%u inode_id=",
(unsigned int)entry->nhe_id);
if (block.nb_inode_entry == NULL) {
NFFS_LOG(DEBUG, "null ");
} else {
NFFS_LOG(DEBUG, "%u ",
(unsigned int)block.nb_inode_entry->nie_hash_entry.nhe_id);
}
NFFS_LOG(DEBUG, "prev_id=");
if (block.nb_prev == NULL) {
NFFS_LOG(DEBUG, "null ");
} else {
NFFS_LOG(DEBUG, "%u ", (unsigned int)block.nb_prev->nhe_id);
}
NFFS_LOG(DEBUG, "data_len=%u\n", block.nb_data_len);
} else {
inode_entry = (void *)entry;
rc = nffs_inode_from_entry(&inode, inode_entry);
if (rc == FS_ENOENT) {
NFFS_LOG(DEBUG, "DUMMY file; id=%x ref=%d block_id=",
(unsigned int)entry->nhe_id, inode_entry->nie_refcnt);
if (inode_entry->nie_last_block_entry == NULL) {
NFFS_LOG(DEBUG, "null");
} else {
NFFS_LOG(DEBUG, "%x",
(unsigned int)inode_entry->nie_last_block_entry->nhe_id);
}
} else if (rc != 0) {
continue;
}
/*assert(rc == 0);*/
if (nffs_hash_id_is_file(entry->nhe_id)) {
NFFS_LOG(DEBUG, "file; id=%u name=%.3s block_id=",
(unsigned int)entry->nhe_id, inode.ni_filename);
if (inode_entry->nie_last_block_entry == NULL) {
NFFS_LOG(DEBUG, "null");
} else {
NFFS_LOG(DEBUG, "%u",
(unsigned int)inode_entry->nie_last_block_entry->nhe_id);
}
NFFS_LOG(DEBUG, "\n");
} else {
inode_entry = (void *)entry;
NFFS_LOG(DEBUG, "dir; id=%u name=%.3s\n",
(unsigned int)entry->nhe_id, inode.ni_filename);
}
}
}
}
