int
testfs_init_super_block(const char *file, struct super_block **sbp)
{
struct super_block *sb = malloc(sizeof(struct super_block));
char block[BLOCK_SIZE];
int ret, sock;
if (!sb) {
return -ENOMEM;
}
if ((sock = open(file, O_RDWR)) < 0) {
return errno;
} else if ((sb->dev = fdopen(sock, "r+")) == NULL) {
return errno;
}
read_blocks(sb, block, 0, 1);
memcpy(&sb->sb, block, sizeof(struct dsuper_block));
ret = bitmap_create(BLOCK_SIZE * INODE_FREEMAP_SIZE * BITS_PER_WORD,
&sb->inode_freemap);
if (ret < 0)
return ret;
read_blocks(sb, bitmap_getdata(sb->inode_freemap),
sb->sb.inode_freemap_start, INODE_FREEMAP_SIZE);
ret = bitmap_create(BLOCK_SIZE * BLOCK_FREEMAP_SIZE * BITS_PER_WORD,
&sb->block_freemap);
if (ret < 0)
return ret;
read_blocks(sb, bitmap_getdata(sb->block_freemap),
sb->sb.block_freemap_start, BLOCK_FREEMAP_SIZE);
inode_hash_init();
*sbp = sb;
return 0;
}
struct super_block *
testfs_make_super_block(char *file) {
struct super_block *sb = calloc(1, sizeof(struct super_block));
if (!sb) {
EXIT("malloc");
}
if ((sb->dev = fopen(file, "w")) == NULL) {
EXIT(file);
}
sb->sb.inode_freemap_start = SUPER_BLOCK_SIZE;
sb->sb.block_freemap_start = sb->sb.inode_freemap_start +
INODE_FREEMAP_SIZE;
sb->sb.csum_table_start = sb->sb.block_freemap_start +
BLOCK_FREEMAP_SIZE;
sb->sb.inode_blocks_start = sb->sb.csum_table_start +
CSUM_TABLE_SIZE;
sb->sb.data_blocks_start = sb->sb.inode_blocks_start + NR_INODE_BLOCKS;
sb->sb.modification_time = 0;
testfs_write_super_block(sb);
inode_hash_init();
return sb;
}
struct super_block *
testfs_make_super_block(const char *dev, u64 max_fs_blocks)
{
struct super_block *sb = calloc(1, sizeof(struct super_block));
if (!sb) {
EXIT("malloc");
}
if ((sb->dev = fopen(dev, "w")) == NULL) {
EXIT(dev);
}
sb->sb.inode_freemap_start = SUPER_BLOCK_SIZE;
sb->sb.block_freemap_start = sb->sb.inode_freemap_start +
INODE_FREEMAP_SIZE;
sb->sb.inode_blocks_start = sb->sb.block_freemap_start +
BLOCK_FREEMAP_SIZE;
sb->sb.data_blocks_start = sb->sb.inode_blocks_start + NR_INODE_BLOCKS;
sb->sb.used_inode_count = 0;
sb->sb.used_block_count = 0;
sb->sb.max_fs_blocks = max_fs_blocks;
testfs_write_super_block(sb);
inode_hash_init();
return sb;
}
/* returns negative value on error
file is name of the disk that was given to testfs.
this function initializes all the in memory data structures maintained by the sb
block.
*/
int testfs_init_super_block(const char *file, int corrupt,
struct super_block **sbp) {
struct super_block *sb = malloc(sizeof(struct super_block));
char block[BLOCK_SIZE];
int ret, sock;
if (!sb) {
return -ENOMEM;
}
if ((sock = open(file, O_RDWR
#ifndef DISABLE_OSYNC
| O_SYNC
#endif
)) < 0) {
return errno;
} else if ((sb->dev = fdopen(sock, "r+")) == NULL) {
return errno;
}
// sb->dev type = FILE
// read from sb into block.
read_blocks(sb, block, 0, 1);
// copy only 24 bytes from block corresponding to dsuper_block
_memcpy(&sb->sb, block, sizeof(struct dsuper_block));
// 64 * 1 * 8
// bitmap create will return a inode_bitmap structure.
// and point sb->inode_freemap to that structure.
// currently the inode bitmap is all 0.
// at the end of this function, bitmap is created in memory
ret = bitmap_create(BLOCK_SIZE * INODE_FREEMAP_SIZE * BITS_PER_WORD,
&sb->inode_freemap);
if (ret < 0)
return ret;
// bitmap_getdata returns v -> the byte array containing bit info
// read_blocks reads sb->v into sb at offset freemap_start till
// INODE_FREEMAP_SIZE
// sb is only sent to read_blocks since we need the sb device handle.
// data from sb->dev is used to populate arg 2 sb->inode_freemap
read_blocks(sb, bitmap_getdata(sb->inode_freemap),
sb->sb.inode_freemap_start, INODE_FREEMAP_SIZE);
ret = bitmap_create(BLOCK_SIZE * BLOCK_FREEMAP_SIZE * BITS_PER_WORD,
&sb->block_freemap);
if (ret < 0)
return ret;
read_blocks(sb, bitmap_getdata(sb->block_freemap),
sb->sb.block_freemap_start, BLOCK_FREEMAP_SIZE);
sb->csum_table = malloc(CSUM_TABLE_SIZE * BLOCK_SIZE);
if (!sb->csum_table)
return -ENOMEM;
read_blocks(sb, (char *) sb->csum_table, sb->sb.csum_table_start,
CSUM_TABLE_SIZE);
sb->tx_in_progress = TX_NONE;
/*
inode_hash_init() initializes inode_hash_table of size 256 bytes
each entry of the inode table contains a first pointer. each
node of the first pointer has a prev pointer and a next pointer.
*/
inode_hash_init();
*sbp = sb;
return 0;
}
