/**
* Constructs a full data block representation from the specified minimal
* block entry. However, the resultant block's pointers are set to null,
* rather than populated via hash table lookups. This behavior is useful when
* the RAM representation has not been fully constructed yet.
*
* @param out_block On success, this gets populated with the data
* block information.
* @param block_entry The source block entry to convert.
*
* @return 0 on success; nonzero on failure.
*/
int
nffs_block_from_hash_entry_no_ptrs(struct nffs_block *out_block,
struct nffs_hash_entry *block_entry)
{
struct nffs_disk_block disk_block;
uint32_t area_offset;
uint8_t area_idx;
int rc;
assert(nffs_hash_id_is_block(block_entry->nhe_id));
if (nffs_hash_entry_is_dummy(block_entry)) {
/*
* We can't read this from disk so we'll be missing filling in anything
* not already in inode_entry (e.g., prev_id).
*/
out_block->nb_hash_entry = block_entry;
return FS_ENOENT; /* let caller know it's a partial inode_entry */
}
nffs_flash_loc_expand(block_entry->nhe_flash_loc, &area_idx, &area_offset);
rc = nffs_block_read_disk(area_idx, area_offset, &disk_block);
if (rc != 0) {
return rc;
}
out_block->nb_hash_entry = block_entry;
nffs_block_from_disk_no_ptrs(out_block, &disk_block);
return 0;
}
static int
nffs_block_from_disk(struct nffs_block *out_block,
const struct nffs_disk_block *disk_block,
uint8_t area_idx, uint32_t area_offset)
{
nffs_block_from_disk_no_ptrs(out_block, disk_block);
out_block->nb_inode_entry = nffs_hash_find_inode(disk_block->ndb_inode_id);
if (out_block->nb_inode_entry == NULL) {
return FS_ECORRUPT;
}
if (disk_block->ndb_prev_id != NFFS_ID_NONE) {
out_block->nb_prev = nffs_hash_find_block(disk_block->ndb_prev_id);
if (out_block->nb_prev == NULL) {
return FS_ECORRUPT;
}
}
return 0;
}
/**
* Constructs a full data block representation from the specified minimal
* block entry. However, the resultant block's pointers are set to null,
* rather than populated via hash table lookups. This behavior is useful when
* the RAM representation has not been fully constructed yet.
*
* @param out_block On success, this gets populated with the data
* block information.
* @param block_entry The source block entry to convert.
*
* @return 0 on success; nonzero on failure.
*/
int
nffs_block_from_hash_entry_no_ptrs(struct nffs_block *out_block,
struct nffs_hash_entry *block_entry)
{
struct nffs_disk_block disk_block;
uint32_t area_offset;
uint8_t area_idx;
int rc;
assert(nffs_hash_id_is_block(block_entry->nhe_id));
nffs_flash_loc_expand(block_entry->nhe_flash_loc, &area_idx, &area_offset);
rc = nffs_block_read_disk(area_idx, area_offset, &disk_block);
if (rc != 0) {
return rc;
}
out_block->nb_hash_entry = block_entry;
nffs_block_from_disk_no_ptrs(out_block, &disk_block);
return 0;
}
/**
* Constructs a block representation from a disk record. If the disk block
* references other objects (inode or previous data block), the resulting block
* object is populated with pointers to the referenced objects. If the any
* referenced objects are not present in the NFFS RAM representation, this
* indicates file system corruption. In this case, the resulting block is
* populated with all valid references, and an FS_ECORRUPT code is returned.
*
* @param out_block The resulting block is written here (regardless
* of this function's return code).
* @param disk_block The source disk record to convert.
*
* @return 0 if the block was successfully constructed;
* FS_ECORRUPT if one or more pointers could not
* be filled in due to file system corruption.
*/
static int
nffs_block_from_disk(struct nffs_block *out_block,
const struct nffs_disk_block *disk_block)
{
int rc;
rc = 0;
nffs_block_from_disk_no_ptrs(out_block, disk_block);
out_block->nb_inode_entry = nffs_hash_find_inode(disk_block->ndb_inode_id);
if (out_block->nb_inode_entry == NULL) {
rc = FS_ECORRUPT;
}
if (disk_block->ndb_prev_id != NFFS_ID_NONE) {
out_block->nb_prev = nffs_hash_find_block(disk_block->ndb_prev_id);
if (out_block->nb_prev == NULL) {
rc = FS_ECORRUPT;
}
}
return rc;
}
