inode.c

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	buf->f_bavail = buf->f_bfree;
	buf->f_files = sb->u.minix_sb.s_ninodes;
	buf->f_ffree = minix_count_free_inodes(sb);
	buf->f_namelen = sb->u.minix_sb.s_namelen;
	return 0;
}

static int minix_get_block(struct inode *inode, long block,
		    struct buffer_head *bh_result, int create)
{
	if (INODE_VERSION(inode) == MINIX_V1)
		return V1_minix_get_block(inode, block, bh_result, create);
	else
		return V2_minix_get_block(inode, block, bh_result, create);
}

/*
 * the global minix fs getblk function.
 */
struct buffer_head *minix_getblk(struct inode *inode, int block, int create)
{
	struct buffer_head dummy;
	int error;

	dummy.b_state = 0;
	dummy.b_blocknr = -1000;
	error = minix_get_block(inode, block, &dummy, create);
	if (!error && buffer_mapped(&dummy)) {
		struct buffer_head *bh;
		bh = getblk(dummy.b_dev, dummy.b_blocknr, BLOCK_SIZE);
		if (buffer_new(&dummy)) {
			memset(bh->b_data, 0, BLOCK_SIZE);
			mark_buffer_uptodate(bh, 1);
			mark_buffer_dirty(bh);
		}
		return bh;
	}
	return NULL;
}

struct buffer_head * minix_bread(struct inode * inode, int block, int create)
{
	struct buffer_head * bh;

	bh = minix_getblk(inode, block, create);
	if (!bh || buffer_uptodate(bh))
		return bh;
	ll_rw_block(READ, 1, &bh);
	wait_on_buffer(bh);
	if (buffer_uptodate(bh))
		return bh;
	brelse(bh);
	return NULL;
}

static int minix_writepage(struct page *page)
{
	return block_write_full_page(page,minix_get_block);
}
static int minix_readpage(struct file *file, struct page *page)
{
	return block_read_full_page(page,minix_get_block);
}
static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
{
	return block_prepare_write(page,from,to,minix_get_block);
}
static int minix_bmap(struct address_space *mapping, long block)
{
	return generic_block_bmap(mapping,block,minix_get_block);
}
struct address_space_operations minix_aops = {
	readpage: minix_readpage,
	writepage: minix_writepage,
	sync_page: block_sync_page,
	prepare_write: minix_prepare_write,
	commit_write: generic_commit_write,
	bmap: minix_bmap
};

/*
 * The minix V1 function to read an inode.
 */
static void V1_minix_read_inode(struct inode * inode)
{
	struct buffer_head * bh;
	struct minix_inode * raw_inode;
	int block, ino;

	ino = inode->i_ino;
	inode->i_mode = 0;
	if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) {
		printk("Bad inode number on dev %s"
		       ": %d is out of range\n",
			kdevname(inode->i_dev), ino);
		return;
	}
	block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks +
		    inode->i_sb->u.minix_sb.s_zmap_blocks +
		    (ino-1)/MINIX_INODES_PER_BLOCK;
	if (!(bh=bread(inode->i_dev,block, BLOCK_SIZE))) {
		printk("Major problem: unable to read inode from dev "
		       "%s\n", kdevname(inode->i_dev));
		return;
	}
	raw_inode = ((struct minix_inode *) bh->b_data) +
		    (ino-1)%MINIX_INODES_PER_BLOCK;
	inode->i_mode = raw_inode->i_mode;
	inode->i_uid = (uid_t)raw_inode->i_uid;
	inode->i_gid = (gid_t)raw_inode->i_gid;
	inode->i_nlink = raw_inode->i_nlinks;
	inode->i_size = raw_inode->i_size;
	inode->i_mtime = inode->i_atime = inode->i_ctime = raw_inode->i_time;
	inode->i_blocks = inode->i_blksize = 0;
	for (block = 0; block < 9; block++)
		inode->u.minix_i.u.i1_data[block] = raw_inode->i_zone[block];
	if (S_ISREG(inode->i_mode)) {
		inode->i_op = &minix_file_inode_operations;
		inode->i_fop = &minix_file_operations;
		inode->i_mapping->a_ops = &minix_aops;
	} else if (S_ISDIR(inode->i_mode)) {
		inode->i_op = &minix_dir_inode_operations;
		inode->i_fop = &minix_dir_operations;
	} else if (S_ISLNK(inode->i_mode)) {
		inode->i_op = &page_symlink_inode_operations;
		inode->i_mapping->a_ops = &minix_aops;
	} else
		init_special_inode(inode, inode->i_mode, raw_inode->i_zone[0]);
	brelse(bh);
}

/*
 * The minix V2 function to read an inode.
 */
static void V2_minix_read_inode(struct inode * inode)
{
	struct buffer_head * bh;
	struct minix2_inode * raw_inode;
	int block, ino;

	ino = inode->i_ino;
	inode->i_mode = 0;
	if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) {
		printk("Bad inode number on dev %s"
		       ": %d is out of range\n",
			kdevname(inode->i_dev), ino);
		return;
	}
	block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks +
		    inode->i_sb->u.minix_sb.s_zmap_blocks +
		    (ino-1)/MINIX2_INODES_PER_BLOCK;
	if (!(bh=bread(inode->i_dev,block, BLOCK_SIZE))) {
		printk("Major problem: unable to read inode from dev "
		       "%s\n", kdevname(inode->i_dev));
		return;
	}
	raw_inode = ((struct minix2_inode *) bh->b_data) +
		    (ino-1)%MINIX2_INODES_PER_BLOCK;
	inode->i_mode = raw_inode->i_mode;
	inode->i_uid = (uid_t)raw_inode->i_uid;
	inode->i_gid = (gid_t)raw_inode->i_gid;
	inode->i_nlink = raw_inode->i_nlinks;
	inode->i_size = raw_inode->i_size;
	inode->i_mtime = raw_inode->i_mtime;
	inode->i_atime = raw_inode->i_atime;
	inode->i_ctime = raw_inode->i_ctime;
	inode->i_blocks = inode->i_blksize = 0;
	for (block = 0; block < 10; block++)
		inode->u.minix_i.u.i2_data[block] = raw_inode->i_zone[block];
	if (S_ISREG(inode->i_mode)) {
		inode->i_op = &minix_file_inode_operations;
		inode->i_fop = &minix_file_operations;
		inode->i_mapping->a_ops = &minix_aops;
	} else if (S_ISDIR(inode->i_mode)) {
		inode->i_op = &minix_dir_inode_operations;
		inode->i_fop = &minix_dir_operations;
	} else if (S_ISLNK(inode->i_mode)) {
		inode->i_op = &page_symlink_inode_operations;
		inode->i_mapping->a_ops = &minix_aops;
	} else
		init_special_inode(inode, inode->i_mode, raw_inode->i_zone[0]);
	brelse(bh);
}

/*
 * The global function to read an inode.
 */
static void minix_read_inode(struct inode * inode)
{
	if (INODE_VERSION(inode) == MINIX_V1)
		V1_minix_read_inode(inode);
	else
		V2_minix_read_inode(inode);
}

/*
 * The minix V1 function to synchronize an inode.
 */
static struct buffer_head * V1_minix_update_inode(struct inode * inode)
{
	struct buffer_head * bh;
	struct minix_inode * raw_inode;
	int ino, block;

	ino = inode->i_ino;
	if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) {
		printk("Bad inode number on dev %s"
		       ": %d is out of range\n",
			kdevname(inode->i_dev), ino);
		return 0;
	}
	block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks + inode->i_sb->u.minix_sb.s_zmap_blocks +
		(ino-1)/MINIX_INODES_PER_BLOCK;
	if (!(bh=bread(inode->i_dev, block, BLOCK_SIZE))) {
		printk("unable to read i-node block\n");
		return 0;
	}
	raw_inode = ((struct minix_inode *)bh->b_data) +
		(ino-1)%MINIX_INODES_PER_BLOCK;
	raw_inode->i_mode = inode->i_mode;
	raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
	raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
	raw_inode->i_nlinks = inode->i_nlink;
	raw_inode->i_size = inode->i_size;
	raw_inode->i_time = inode->i_mtime;
	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
		raw_inode->i_zone[0] = kdev_t_to_nr(inode->i_rdev);
	else for (block = 0; block < 9; block++)
		raw_inode->i_zone[block] = inode->u.minix_i.u.i1_data[block];
	mark_buffer_dirty(bh);
	return bh;
}

/*
 * The minix V2 function to synchronize an inode.
 */
static struct buffer_head * V2_minix_update_inode(struct inode * inode)
{
	struct buffer_head * bh;
	struct minix2_inode * raw_inode;
	int ino, block;

	ino = inode->i_ino;
	if (!ino || ino > inode->i_sb->u.minix_sb.s_ninodes) {
		printk("Bad inode number on dev %s"
		       ": %d is out of range\n",
			kdevname(inode->i_dev), ino);
		return 0;
	}
	block = 2 + inode->i_sb->u.minix_sb.s_imap_blocks + inode->i_sb->u.minix_sb.s_zmap_blocks +
		(ino-1)/MINIX2_INODES_PER_BLOCK;
	if (!(bh=bread(inode->i_dev, block, BLOCK_SIZE))) {
		printk("unable to read i-node block\n");
		return 0;
	}
	raw_inode = ((struct minix2_inode *)bh->b_data) +
		(ino-1)%MINIX2_INODES_PER_BLOCK;
	raw_inode->i_mode = inode->i_mode;
	raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
	raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
	raw_inode->i_nlinks = inode->i_nlink;
	raw_inode->i_size = inode->i_size;
	raw_inode->i_mtime = inode->i_mtime;
	raw_inode->i_atime = inode->i_atime;
	raw_inode->i_ctime = inode->i_ctime;
	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
		raw_inode->i_zone[0] = kdev_t_to_nr(inode->i_rdev);
	else for (block = 0; block < 10; block++)
		raw_inode->i_zone[block] = inode->u.minix_i.u.i2_data[block];
	mark_buffer_dirty(bh);
	return bh;
}

static struct buffer_head *minix_update_inode(struct inode *inode)
{
	if (INODE_VERSION(inode) == MINIX_V1)
		return V1_minix_update_inode(inode);
	else
		return V2_minix_update_inode(inode);
}

static void minix_write_inode(struct inode * inode, int wait)
{
	struct buffer_head *bh;

	lock_kernel();
	bh = minix_update_inode(inode);
	unlock_kernel();
	brelse(bh);
}

int minix_sync_inode(struct inode * inode)
{
	int err = 0;
	struct buffer_head *bh;

	bh = minix_update_inode(inode);
	if (bh && buffer_dirty(bh))
	{
		ll_rw_block(WRITE, 1, &bh);
		wait_on_buffer(bh);
		if (buffer_req(bh) && !buffer_uptodate(bh))
		{
			printk ("IO error syncing minix inode ["
				"%s:%08lx]\n",
				kdevname(inode->i_dev), inode->i_ino);
			err = -1;
		}
	}
	else if (!bh)
		err = -1;
	brelse (bh);
	return err;
}

/*
 * The function that is called for file truncation.
 */
void minix_truncate(struct inode * inode)
{
	if (INODE_VERSION(inode) == MINIX_V1)
		V1_minix_truncate(inode);
	else
		V2_minix_truncate(inode);
}

static DECLARE_FSTYPE_DEV(minix_fs_type,"minix",minix_read_super);

static int __init init_minix_fs(void)
{
        return register_filesystem(&minix_fs_type);
}

static void __exit exit_minix_fs(void)
{
        unregister_filesystem(&minix_fs_type);
}

EXPORT_NO_SYMBOLS;

module_init(init_minix_fs)
module_exit(exit_minix_fs)