[linux-2.6-block.git] / fs / btrfs / super.c

#include <linux/module.h>
#include <linux/buffer_head.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/smp_lock.h>
#include <linux/backing-dev.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"

#define BTRFS_SUPER_MAGIC 0x9123682E

static struct inode_operations btrfs_dir_inode_operations;
static struct super_operations btrfs_super_ops;
static struct file_operations btrfs_dir_file_operations;

#if 0
/* some random number */

static struct super_operations ramfs_ops;

static struct backing_dev_info ramfs_backing_dev_info = {
	.ra_pages	= 0,	/* No readahead */
	.capabilities	= BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK |
			  BDI_CAP_MAP_DIRECT | BDI_CAP_MAP_COPY |
			  BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP,
};

struct inode *ramfs_get_inode(struct super_block *sb, int mode, dev_t dev)
{
	struct inode * inode = new_inode(sb);

	if (inode) {
		inode->i_mode = mode;
		inode->i_uid = current->fsuid;
		inode->i_gid = current->fsgid;
		inode->i_blocks = 0;
		inode->i_mapping->a_ops = &ramfs_aops;
		inode->i_mapping->backing_dev_info = &ramfs_backing_dev_info;
		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
		switch (mode & S_IFMT) {
		default:
			init_special_inode(inode, mode, dev);
			break;
		case S_IFREG:
			inode->i_op = &ramfs_file_inode_operations;
			inode->i_fop = &ramfs_file_operations;
			break;
		case S_IFDIR:
			inode->i_op = &ramfs_dir_inode_operations;
			inode->i_fop = &simple_dir_operations;

			/* directory inodes start off with i_nlink == 2 (for "." entry) */
			inc_nlink(inode);
			break;
		case S_IFLNK:
			inode->i_op = &page_symlink_inode_operations;
			break;
		}
	}
	return inode;
}

/*
 * File creation. Allocate an inode, and we're done..
 */
/* SMP-safe */
static int
ramfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
	struct inode * inode = ramfs_get_inode(dir->i_sb, mode, dev);
	int error = -ENOSPC;

	if (inode) {
		if (dir->i_mode & S_ISGID) {
			inode->i_gid = dir->i_gid;
			if (S_ISDIR(mode))
				inode->i_mode |= S_ISGID;
		}
		d_instantiate(dentry, inode);
		dget(dentry);	/* Extra count - pin the dentry in core */
		error = 0;
		dir->i_mtime = dir->i_ctime = CURRENT_TIME;
	}
	return error;
}

static int ramfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
{
	int retval = ramfs_mknod(dir, dentry, mode | S_IFDIR, 0);
	if (!retval)
		inc_nlink(dir);
	return retval;
}

static int ramfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd)
{
	return ramfs_mknod(dir, dentry, mode | S_IFREG, 0);
}

static int ramfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
{
	struct inode *inode;
	int error = -ENOSPC;

	inode = ramfs_get_inode(dir->i_sb, S_IFLNK|S_IRWXUGO, 0);
	if (inode) {
		int l = strlen(symname)+1;
		error = page_symlink(inode, symname, l);
		if (!error) {
			if (dir->i_mode & S_ISGID)
				inode->i_gid = dir->i_gid;
			d_instantiate(dentry, inode);
			dget(dentry);
			dir->i_mtime = dir->i_ctime = CURRENT_TIME;
		} else
			iput(inode);
	}
	return error;
}

static struct inode_operations ramfs_dir_inode_operations = {
	.create		= ramfs_create,
	.lookup		= simple_lookup,
	.link		= simple_link,
	.unlink		= simple_unlink,
	.symlink	= ramfs_symlink,
	.mkdir		= ramfs_mkdir,
	.rmdir		= simple_rmdir,
	.mknod		= ramfs_mknod,
	.rename		= simple_rename,
};
#endif

static void btrfs_read_locked_inode(struct inode *inode)
{
	struct btrfs_path path;
	struct btrfs_inode_item *inode_item;
	struct btrfs_root *root = btrfs_sb(inode->i_sb);
	int ret;
	btrfs_init_path(&path);
	ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
	if (ret) {
		make_bad_inode(inode);
		btrfs_release_path(root, &path);
		return;
	}
	inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
				  path.slots[0],
				  struct btrfs_inode_item);

	inode->i_mode = btrfs_inode_mode(inode_item);
	inode->i_nlink = btrfs_inode_nlink(inode_item);
	inode->i_uid = btrfs_inode_uid(inode_item);
	inode->i_gid = btrfs_inode_gid(inode_item);
	inode->i_size = btrfs_inode_size(inode_item);
	inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
	inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
	inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
	inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
	inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
	inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
	inode->i_blocks = btrfs_inode_nblocks(inode_item);
	inode->i_generation = btrfs_inode_generation(inode_item);
	btrfs_release_path(root, &path);
	switch (inode->i_mode & S_IFMT) {
#if 0
	default:
		init_special_inode(inode, inode->i_mode,
				   btrfs_inode_rdev(inode_item));
		break;
#endif
	case S_IFREG:
		break;
	case S_IFDIR:
		inode->i_op = &btrfs_dir_inode_operations;
		inode->i_fop = &btrfs_dir_file_operations;
		break;
	case S_IFLNK:
		// inode->i_op = &page_symlink_inode_operations;
		break;
	}
	return;
}

static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
{
	struct btrfs_path path;
	struct btrfs_root *root;
	struct btrfs_trans_handle *trans;
	const char *name = dentry->d_name.name;
	int name_len = dentry->d_name.len;
	int ret;
	u64 objectid;
	struct btrfs_dir_item *di;

	btrfs_init_path(&path);
	root = btrfs_sb(dir->i_sb);
	mutex_lock(&root->fs_info->fs_mutex);
	trans = btrfs_start_transaction(root, 1);

	ret = btrfs_lookup_dir_item(trans, root, &path, dir->i_ino,
				    name, name_len, -1);
	if (ret < 0)
		goto err;
	if (ret > 0) {
		ret = -ENOENT;
		goto err;
	}
	di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
			    struct btrfs_dir_item);
	objectid = btrfs_dir_objectid(di);

	ret = btrfs_del_item(trans, root, &path);
	BUG_ON(ret);
	dentry->d_inode->i_ctime = dir->i_ctime;
err:
	btrfs_release_path(root, &path);
	btrfs_end_transaction(trans, root);
	mutex_unlock(&root->fs_info->fs_mutex);
	if (ret == 0)
		inode_dec_link_count(dentry->d_inode);
	return ret;
}

static int btrfs_free_inode(struct btrfs_trans_handle *trans,
			    struct btrfs_root *root,
			    struct inode *inode)
{
	u64 objectid = inode->i_ino;
	struct btrfs_path path;
	struct btrfs_inode_map_item *map;
	struct btrfs_key stat_data_key;
	int ret;
	clear_inode(inode);
	btrfs_init_path(&path);
	ret = btrfs_lookup_inode_map(trans, root, &path, objectid, -1);
	if (ret) {
		if (ret > 0)
			ret = -ENOENT;
		btrfs_release_path(root, &path);
		goto error;
	}
	map = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
			    struct btrfs_inode_map_item);
	btrfs_disk_key_to_cpu(&stat_data_key, &map->key);
	ret = btrfs_del_item(trans, root->fs_info->inode_root, &path);
	BUG_ON(ret);
	btrfs_release_path(root, &path);
	btrfs_init_path(&path);

	ret = btrfs_lookup_inode(trans, root, &path, objectid, -1);
	BUG_ON(ret);
	ret = btrfs_del_item(trans, root, &path);
	BUG_ON(ret);
	btrfs_release_path(root, &path);
error:
	return ret;
}

static void btrfs_delete_inode(struct inode *inode)
{
	struct btrfs_trans_handle *trans;
	struct btrfs_root *root = btrfs_sb(inode->i_sb);
	truncate_inode_pages(&inode->i_data, 0);
	if (is_bad_inode(inode)) {
		goto no_delete;
	}
	inode->i_size = 0;
	if (inode->i_blocks)
		WARN_ON(1);

	mutex_lock(&root->fs_info->fs_mutex);
	trans = btrfs_start_transaction(root, 1);
	btrfs_free_inode(trans, root, inode);
	btrfs_end_transaction(trans, root);
	mutex_unlock(&root->fs_info->fs_mutex);
	return;
no_delete:
	clear_inode(inode);
}


static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
			      ino_t *ino)
{
	const char *name = dentry->d_name.name;
	int namelen = dentry->d_name.len;
	struct btrfs_dir_item *di;
	struct btrfs_path path;
	struct btrfs_root *root = btrfs_sb(dir->i_sb);
	int ret;

	btrfs_init_path(&path);
	ret = btrfs_lookup_dir_item(NULL, root, &path, dir->i_ino, name,
				    namelen, 0);
	if (ret || !btrfs_match_dir_item_name(root, &path, name, namelen)) {
		*ino = 0;
		goto out;
	}
	di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
			    struct btrfs_dir_item);
	*ino = btrfs_dir_objectid(di);
out:
	btrfs_release_path(root, &path);
	return ret;
}

static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
				   struct nameidata *nd)
{
	struct inode * inode;
	ino_t ino;
	int ret;

	if (dentry->d_name.len > BTRFS_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

	ret = btrfs_inode_by_name(dir, dentry, &ino);
	if (ret < 0)
		return ERR_PTR(ret);
	inode = NULL;
	if (ino) {
		inode = iget(dir->i_sb, ino);
		if (!inode)
			return ERR_PTR(-EACCES);
	}
	return d_splice_alias(inode, dentry);
}

static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
	struct inode *inode = filp->f_path.dentry->d_inode;
	struct btrfs_root *root = btrfs_sb(inode->i_sb);
	struct btrfs_item *item;
	struct btrfs_dir_item *di;
	struct btrfs_key key;
	struct btrfs_path path;
	int ret;
	u32 nritems;
	struct btrfs_leaf *leaf;
	int slot;
	int advance;
	unsigned char d_type = DT_UNKNOWN;
	int over = 0;

	key.objectid = inode->i_ino;
	key.flags = 0;
	btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
	key.offset = filp->f_pos;
	btrfs_init_path(&path);
	ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
	if (ret < 0) {
		goto err;
	}
	advance = 0;
	while(1) {
		leaf = btrfs_buffer_leaf(path.nodes[0]);
		nritems = btrfs_header_nritems(&leaf->header);
		slot = path.slots[0];
		if (advance) {
			if (slot == nritems -1) {
				ret = btrfs_next_leaf(root, &path);
				if (ret)
					break;
				leaf = btrfs_buffer_leaf(path.nodes[0]);
				nritems = btrfs_header_nritems(&leaf->header);
				slot = path.slots[0];
#if 0
				page_cache_readahead(
				     inode->i_sb->s_bdev->bd_inode->i_mapping,
				     &filp->f_ra, filp,
				     path.nodes[0]->b_blocknr >>
				     (PAGE_CACHE_SHIFT - inode->i_blkbits), 1);
#endif
			} else {
				slot++;
				path.slots[0]++;
			}
		}
		advance = 1;
		item = leaf->items + slot;
		if (btrfs_disk_key_objectid(&item->key) != key.objectid)
			break;
		if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
			continue;
		if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
			continue;
		di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
		over = filldir(dirent, (const char *)(di + 1),
			       btrfs_dir_name_len(di),
			       btrfs_disk_key_offset(&item->key),
			       btrfs_dir_objectid(di), d_type);
		if (over) {
			filp->f_pos = btrfs_disk_key_offset(&item->key);
			break;
		}
		filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
	}
	ret = 0;
err:
	btrfs_release_path(root, &path);
	return ret;
}

static void btrfs_put_super (struct super_block * sb)
{
	struct btrfs_root *root = btrfs_sb(sb);
	int ret;

	ret = close_ctree(root);
	if (ret) {
		printk("close ctree returns %d\n", ret);
	}
	sb->s_fs_info = NULL;
}

static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
{
	struct inode * inode;
	struct dentry * root_dentry;
	struct btrfs_super_block *disk_super;
	struct buffer_head *bh;
	struct btrfs_root *root;

	sb->s_maxbytes = MAX_LFS_FILESIZE;
	sb->s_blocksize = PAGE_CACHE_SIZE;
	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	sb->s_magic = BTRFS_SUPER_MAGIC;
	sb->s_op = &btrfs_super_ops;
	sb->s_time_gran = 1;

	bh = sb_bread(sb, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize);
	if (!bh) {
		printk("btrfs: unable to read on disk super\n");
		return -EIO;
	}
	disk_super = (struct btrfs_super_block *)bh->b_data;
	root = open_ctree(sb, bh, disk_super);
	sb->s_fs_info = root;
	if (!root) {
		printk("btrfs: open_ctree failed\n");
		return -EIO;
	}
	printk("read in super total blocks %Lu root %Lu\n",
	       btrfs_super_total_blocks(disk_super),
	       btrfs_super_root_dir(disk_super));

	inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
	if (!inode)
		return -ENOMEM;
	if (inode->i_state & I_NEW) {
		btrfs_read_locked_inode(inode);
		unlock_new_inode(inode);
	}

	root_dentry = d_alloc_root(inode);
	if (!root_dentry) {
		iput(inode);
		return -ENOMEM;
	}
	sb->s_root = root_dentry;

	return 0;
}

static void fill_inode_item(struct btrfs_inode_item *item,
			    struct inode *inode)
{
	btrfs_set_inode_uid(item, inode->i_uid);
	btrfs_set_inode_gid(item, inode->i_gid);
	btrfs_set_inode_size(item, inode->i_size);
	btrfs_set_inode_mode(item, inode->i_mode);
	btrfs_set_inode_nlink(item, inode->i_nlink);
	btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
	btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
	btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
	btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
	btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
	btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
	btrfs_set_inode_nblocks(item, inode->i_blocks);
	btrfs_set_inode_generation(item, inode->i_generation);
}

static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
				     struct inode *dir, int mode)
{
	struct inode *inode;
	struct btrfs_inode_item inode_item;
	struct btrfs_root *root = btrfs_sb(dir->i_sb);
	struct btrfs_key key;
	int ret;
	u64 objectid;

	inode = new_inode(dir->i_sb);
	if (!inode)
		return ERR_PTR(-ENOMEM);

	ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
	BUG_ON(ret);

	inode->i_uid = current->fsuid;
	inode->i_gid = current->fsgid;
	inode->i_mode = mode;
	inode->i_ino = objectid;
	inode->i_blocks = 0;
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
	fill_inode_item(&inode_item, inode);


	key.objectid = objectid;
	key.flags = 0;
	key.offset = 0;
	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
	ret = btrfs_insert_inode_map(trans, root, objectid, &key);
	BUG_ON(ret);

	ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
	BUG_ON(ret);

	insert_inode_hash(inode);
	// FIXME mark_inode_dirty(inode)
	return inode;
}

static int btrfs_add_link(struct btrfs_trans_handle *trans,
			    struct dentry *dentry, struct inode *inode)
{
	int ret;
	ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
				    dentry->d_name.name, dentry->d_name.len,
				    dentry->d_parent->d_inode->i_ino,
				    inode->i_ino, 0);
	return ret;
}

static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
			    struct dentry *dentry, struct inode *inode)
{
	int err = btrfs_add_link(trans, dentry, inode);
	if (!err) {
		d_instantiate(dentry, inode);
		return 0;
	}
	return err;
}

static int btrfs_create(struct inode *dir, struct dentry *dentry,
			int mode, struct nameidata *nd)
{
	struct btrfs_trans_handle *trans;
	struct btrfs_root *root = btrfs_sb(dir->i_sb);
	struct inode *inode;
	int err;
	int drop_inode = 0;

	mutex_lock(&root->fs_info->fs_mutex);
	trans = btrfs_start_transaction(root, 1);
	inode = btrfs_new_inode(trans, dir, mode);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out_unlock;
	// FIXME mark the inode dirty
	err = btrfs_add_nondir(trans, dentry, inode);
	if (err)
		drop_inode = 1;
	dir->i_sb->s_dirt = 1;
	btrfs_end_transaction(trans, root);
out_unlock:
	mutex_unlock(&root->fs_info->fs_mutex);
	if (drop_inode) {
		inode_dec_link_count(inode);
		iput(inode);
	}
	return err;
}

static int btrfs_sync_fs(struct super_block *sb, int wait)
{
	struct btrfs_trans_handle *trans;
	struct btrfs_root *root;
	int ret;

	sb->s_dirt = 0;
	if (!wait) {
		filemap_flush(sb->s_bdev->bd_inode->i_mapping);
		return 0;
	}
	filemap_write_and_wait(sb->s_bdev->bd_inode->i_mapping);

	root = btrfs_sb(sb);
	mutex_lock(&root->fs_info->fs_mutex);
	trans = btrfs_start_transaction(root, 1);
	ret = btrfs_commit_transaction(trans, root);
	sb->s_dirt = 0;
	BUG_ON(ret);
printk("btrfs sync_fs\n");
	mutex_unlock(&root->fs_info->fs_mutex);
	return 0;
}

static void btrfs_write_super(struct super_block *sb)
{
	btrfs_sync_fs(sb, 1);
}


static int btrfs_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
	return get_sb_bdev(fs_type, flags, dev_name, data,
			   btrfs_fill_super, mnt);
}

static struct file_system_type btrfs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "btrfs",
	.get_sb		= btrfs_get_sb,
	.kill_sb	= kill_block_super,
	.fs_flags	= FS_REQUIRES_DEV,
};

static struct super_operations btrfs_super_ops = {
	.statfs		= simple_statfs,
	.delete_inode	= btrfs_delete_inode,
	.put_super	= btrfs_put_super,
	.read_inode	= btrfs_read_locked_inode,
	.write_super	= btrfs_write_super,
	.sync_fs	= btrfs_sync_fs,
};

static struct inode_operations btrfs_dir_inode_operations = {
	.lookup		= btrfs_lookup,
	.create		= btrfs_create,
	.unlink		= btrfs_unlink,
};

static struct file_operations btrfs_dir_file_operations = {
	.llseek		= generic_file_llseek,
	.read		= generic_read_dir,
	.readdir	= btrfs_readdir,
};


static int __init init_btrfs_fs(void)
{
	printk("btrfs loaded!\n");
	return register_filesystem(&btrfs_fs_type);
}

static void __exit exit_btrfs_fs(void)
{
	unregister_filesystem(&btrfs_fs_type);
	printk("btrfs unloaded\n");
}

module_init(init_btrfs_fs)
module_exit(exit_btrfs_fs)

MODULE_LICENSE("GPL");
Commit	Line	Data
2e635a27	1	#include <linux/module.h>
e20d96d6	2	#include <linux/buffer_head.h>
2e635a27 CM	3	#include <linux/fs.h>
	4	#include <linux/pagemap.h>
	5	#include <linux/highmem.h>
	6	#include <linux/time.h>
	7	#include <linux/init.h>
	8	#include <linux/string.h>
	9	#include <linux/smp_lock.h>
	10	#include <linux/backing-dev.h>
	11	#include "ctree.h"
e20d96d6	12	#include "disk-io.h"
d5719762	13	#include "transaction.h"
2e635a27 CM	14
2e635a27 CM	15	#define BTRFS_SUPER_MAGIC 0x9123682E
e20d96d6 CM	16
	17	static struct inode_operations btrfs_dir_inode_operations;
	18	static struct super_operations btrfs_super_ops;
	19	static struct file_operations btrfs_dir_file_operations;
	20
2e635a27 CM	21	#if 0
	22	/* some random number */
	23
	24	static struct super_operations ramfs_ops;
2e635a27 CM	25
	26	static struct backing_dev_info ramfs_backing_dev_info = {
	27	.ra_pages = 0, /* No readahead */
	28	.capabilities = BDI_CAP_NO_ACCT_DIRTY \| BDI_CAP_NO_WRITEBACK \|
	29	BDI_CAP_MAP_DIRECT \| BDI_CAP_MAP_COPY \|
	30	BDI_CAP_READ_MAP \| BDI_CAP_WRITE_MAP \| BDI_CAP_EXEC_MAP,
	31	};
	32
	33	struct inode ramfs_get_inode(struct super_block sb, int mode, dev_t dev)
	34	{
	35	struct inode * inode = new_inode(sb);
	36
	37	if (inode) {
	38	inode->i_mode = mode;
	39	inode->i_uid = current->fsuid;
	40	inode->i_gid = current->fsgid;
	41	inode->i_blocks = 0;
	42	inode->i_mapping->a_ops = &ramfs_aops;
	43	inode->i_mapping->backing_dev_info = &ramfs_backing_dev_info;
	44	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	45	switch (mode & S_IFMT) {
	46	default:
	47	init_special_inode(inode, mode, dev);
	48	break;
	49	case S_IFREG:
	50	inode->i_op = &ramfs_file_inode_operations;
	51	inode->i_fop = &ramfs_file_operations;
	52	break;
	53	case S_IFDIR:
	54	inode->i_op = &ramfs_dir_inode_operations;
	55	inode->i_fop = &simple_dir_operations;
	56
	57	/* directory inodes start off with i_nlink == 2 (for "." entry) */
	58	inc_nlink(inode);
	59	break;
	60	case S_IFLNK:
	61	inode->i_op = &page_symlink_inode_operations;
	62	break;
	63	}
	64	}
	65	return inode;
	66	}
	67
	68	/*
	69	* File creation. Allocate an inode, and we're done..
	70	*/
	71	/* SMP-safe */
	72	static int
	73	ramfs_mknod(struct inode dir, struct dentry dentry, int mode, dev_t dev)
	74	{
	75	struct inode * inode = ramfs_get_inode(dir->i_sb, mode, dev);
	76	int error = -ENOSPC;
	77
	78	if (inode) {
	79	if (dir->i_mode & S_ISGID) {
	80	inode->i_gid = dir->i_gid;
	81	if (S_ISDIR(mode))
	82	inode->i_mode \|= S_ISGID;
	83	}
	84	d_instantiate(dentry, inode);
	85	dget(dentry); /* Extra count - pin the dentry in core */
	86	error = 0;
	87	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
	88	}
89	return error;
90	}
91
92	static int ramfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
93	{
94	int retval = ramfs_mknod(dir, dentry, mode \| S_IFDIR, 0);
95	if (!retval)
96	inc_nlink(dir);
97	return retval;
98	}
99
100	static int ramfs_create(struct inode dir, struct dentry dentry, int mode, struct nameidata *nd)
101	{
102	return ramfs_mknod(dir, dentry, mode \| S_IFREG, 0);
103	}
104
105	static int ramfs_symlink(struct inode * dir, struct dentry dentry, const char symname)
106	{
107	struct inode *inode;
108	int error = -ENOSPC;
109
110	inode = ramfs_get_inode(dir->i_sb, S_IFLNK\|S_IRWXUGO, 0);
111	if (inode) {
112	int l = strlen(symname)+1;
113	error = page_symlink(inode, symname, l);
114	if (!error) {
115	if (dir->i_mode & S_ISGID)
116	inode->i_gid = dir->i_gid;
117	d_instantiate(dentry, inode);
118	dget(dentry);
119	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
120	} else
121	iput(inode);
122	}
123	return error;
124	}
125
126	static struct inode_operations ramfs_dir_inode_operations = {
127	.create = ramfs_create,
128	.lookup = simple_lookup,
129	.link = simple_link,
130	.unlink = simple_unlink,
131	.symlink = ramfs_symlink,
132	.mkdir = ramfs_mkdir,
133	.rmdir = simple_rmdir,
134	.mknod = ramfs_mknod,
135	.rename = simple_rename,
136	};
137	#endif
138
e20d96d6	139	static void btrfs_read_locked_inode(struct inode *inode)
2e635a27	140	{
e20d96d6 CM	141	struct btrfs_path path;
	142	struct btrfs_inode_item *inode_item;
	143	struct btrfs_root *root = btrfs_sb(inode->i_sb);
	144	int ret;
e20d96d6 CM	145	btrfs_init_path(&path);
	146	ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
	147	if (ret) {
	148	make_bad_inode(inode);
78fae27e	149	btrfs_release_path(root, &path);
e20d96d6 CM	150	return;
	151	}
	152	inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
	153	path.slots[0],
	154	struct btrfs_inode_item);
2e635a27	155
e20d96d6 CM	156	inode->i_mode = btrfs_inode_mode(inode_item);
	157	inode->i_nlink = btrfs_inode_nlink(inode_item);
	158	inode->i_uid = btrfs_inode_uid(inode_item);
	159	inode->i_gid = btrfs_inode_gid(inode_item);
	160	inode->i_size = btrfs_inode_size(inode_item);
	161	inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
	162	inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
	163	inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
	164	inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
	165	inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
	166	inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
	167	inode->i_blocks = btrfs_inode_nblocks(inode_item);
	168	inode->i_generation = btrfs_inode_generation(inode_item);
e20d96d6 CM	169	btrfs_release_path(root, &path);
	170	switch (inode->i_mode & S_IFMT) {
	171	#if 0
	172	default:
	173	init_special_inode(inode, inode->i_mode,
	174	btrfs_inode_rdev(inode_item));
	175	break;
	176	#endif
	177	case S_IFREG:
e20d96d6 CM	178	break;
e20d96d6 CM	179	case S_IFDIR:
e20d96d6 CM	180	inode->i_op = &btrfs_dir_inode_operations;
	181	inode->i_fop = &btrfs_dir_file_operations;
	182	break;
	183	case S_IFLNK:
e20d96d6 CM	184	// inode->i_op = &page_symlink_inode_operations;
e20d96d6 CM	185	break;
2e635a27	186	}
e20d96d6	187	return;
2e635a27 CM	188	}
2e635a27 CM	189
134e9731 CM	190	static int btrfs_unlink(struct inode dir, struct dentry dentry)
	191	{
	192	struct btrfs_path path;
	193	struct btrfs_root *root;
	194	struct btrfs_trans_handle *trans;
	195	const char *name = dentry->d_name.name;
	196	int name_len = dentry->d_name.len;
	197	int ret;
	198	u64 objectid;
	199	struct btrfs_dir_item *di;
	200
	201	btrfs_init_path(&path);
	202	root = btrfs_sb(dir->i_sb);
	203	mutex_lock(&root->fs_info->fs_mutex);
	204	trans = btrfs_start_transaction(root, 1);
	205
	206	ret = btrfs_lookup_dir_item(trans, root, &path, dir->i_ino,
	207	name, name_len, -1);
	208	if (ret < 0)
	209	goto err;
	210	if (ret > 0) {
	211	ret = -ENOENT;
	212	goto err;
	213	}
	214	di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
	215	struct btrfs_dir_item);
	216	objectid = btrfs_dir_objectid(di);
	217
	218	ret = btrfs_del_item(trans, root, &path);
	219	BUG_ON(ret);
	220	dentry->d_inode->i_ctime = dir->i_ctime;
	221	err:
	222	btrfs_release_path(root, &path);
	223	btrfs_end_transaction(trans, root);
	224	mutex_unlock(&root->fs_info->fs_mutex);
	225	if (ret == 0)
	226	inode_dec_link_count(dentry->d_inode);
	227	return ret;
	228	}
	229
	230	static int btrfs_free_inode(struct btrfs_trans_handle *trans,
	231	struct btrfs_root *root,
	232	struct inode *inode)
	233	{
	234	u64 objectid = inode->i_ino;
	235	struct btrfs_path path;
	236	struct btrfs_inode_map_item *map;
	237	struct btrfs_key stat_data_key;
	238	int ret;
	239	clear_inode(inode);
	240	btrfs_init_path(&path);
	241	ret = btrfs_lookup_inode_map(trans, root, &path, objectid, -1);
	242	if (ret) {
	243	if (ret > 0)
	244	ret = -ENOENT;
	245	btrfs_release_path(root, &path);
	246	goto error;
	247	}
	248	map = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
	249	struct btrfs_inode_map_item);
	250	btrfs_disk_key_to_cpu(&stat_data_key, &map->key);
	251	ret = btrfs_del_item(trans, root->fs_info->inode_root, &path);
	252	BUG_ON(ret);
	253	btrfs_release_path(root, &path);
254	btrfs_init_path(&path);
255
256	ret = btrfs_lookup_inode(trans, root, &path, objectid, -1);
257	BUG_ON(ret);
258	ret = btrfs_del_item(trans, root, &path);
259	BUG_ON(ret);
260	btrfs_release_path(root, &path);
261	error:
262	return ret;
263	}
264
265	static void btrfs_delete_inode(struct inode *inode)
266	{
267	struct btrfs_trans_handle *trans;
268	struct btrfs_root *root = btrfs_sb(inode->i_sb);
269	truncate_inode_pages(&inode->i_data, 0);
270	if (is_bad_inode(inode)) {
271	goto no_delete;
272	}
273	inode->i_size = 0;
274	if (inode->i_blocks)
275	WARN_ON(1);
276
277	mutex_lock(&root->fs_info->fs_mutex);
278	trans = btrfs_start_transaction(root, 1);
279	btrfs_free_inode(trans, root, inode);
280	btrfs_end_transaction(trans, root);
281	mutex_unlock(&root->fs_info->fs_mutex);
282	return;
283	no_delete:
284	clear_inode(inode);
285	}
286
287
e20d96d6 CM	288	static int btrfs_inode_by_name(struct inode dir, struct dentry dentry,
	289	ino_t *ino)
	290	{
	291	const char *name = dentry->d_name.name;
	292	int namelen = dentry->d_name.len;
	293	struct btrfs_dir_item *di;
	294	struct btrfs_path path;
	295	struct btrfs_root *root = btrfs_sb(dir->i_sb);
	296	int ret;
	297
	298	btrfs_init_path(&path);
	299	ret = btrfs_lookup_dir_item(NULL, root, &path, dir->i_ino, name,
	300	namelen, 0);
7f5c1516	301	if (ret \|\| !btrfs_match_dir_item_name(root, &path, name, namelen)) {
e20d96d6 CM	302	*ino = 0;
	303	goto out;
	304	}
	305	di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
	306	struct btrfs_dir_item);
	307	*ino = btrfs_dir_objectid(di);
	308	out:
	309	btrfs_release_path(root, &path);
	310	return ret;
	311	}
	312
	313	static struct dentry btrfs_lookup(struct inode dir, struct dentry *dentry,
	314	struct nameidata *nd)
	315	{
	316	struct inode * inode;
	317	ino_t ino;
	318	int ret;
	319
	320	if (dentry->d_name.len > BTRFS_NAME_LEN)
	321	return ERR_PTR(-ENAMETOOLONG);
	322
	323	ret = btrfs_inode_by_name(dir, dentry, &ino);
	324	if (ret < 0)
	325	return ERR_PTR(ret);
	326	inode = NULL;
	327	if (ino) {
e20d96d6 CM	328	inode = iget(dir->i_sb, ino);
	329	if (!inode)
	330	return ERR_PTR(-EACCES);
	331	}
	332	return d_splice_alias(inode, dentry);
	333	}
	334
	335	static int btrfs_readdir(struct file filp, void dirent, filldir_t filldir)
	336	{
	337	struct inode *inode = filp->f_path.dentry->d_inode;
	338	struct btrfs_root *root = btrfs_sb(inode->i_sb);
	339	struct btrfs_item *item;
	340	struct btrfs_dir_item *di;
	341	struct btrfs_key key;
	342	struct btrfs_path path;
	343	int ret;
	344	u32 nritems;
	345	struct btrfs_leaf *leaf;
	346	int slot;
	347	int advance;
	348	unsigned char d_type = DT_UNKNOWN;
7f5c1516	349	int over = 0;
e20d96d6 CM	350
e20d96d6 CM	351	key.objectid = inode->i_ino;
e20d96d6 CM	352	key.flags = 0;
	353	btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
	354	key.offset = filp->f_pos;
	355	btrfs_init_path(&path);
	356	ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
	357	if (ret < 0) {
	358	goto err;
	359	}
7f5c1516	360	advance = 0;
e20d96d6 CM	361	while(1) {
	362	leaf = btrfs_buffer_leaf(path.nodes[0]);
	363	nritems = btrfs_header_nritems(&leaf->header);
	364	slot = path.slots[0];
e20d96d6	365	if (advance) {
e20d96d6 CM	366	if (slot == nritems -1) {
	367	ret = btrfs_next_leaf(root, &path);
	368	if (ret)
	369	break;
	370	leaf = btrfs_buffer_leaf(path.nodes[0]);
	371	nritems = btrfs_header_nritems(&leaf->header);
	372	slot = path.slots[0];
134e9731 CM	373	#if 0
	374	page_cache_readahead(
	375	inode->i_sb->s_bdev->bd_inode->i_mapping,
	376	&filp->f_ra, filp,
	377	path.nodes[0]->b_blocknr >>
	378	(PAGE_CACHE_SHIFT - inode->i_blkbits), 1);
	379	#endif
e20d96d6 CM	380	} else {
	381	slot++;
	382	path.slots[0]++;
	383	}
	384	}
	385	advance = 1;
	386	item = leaf->items + slot;
e20d96d6 CM	387	if (btrfs_disk_key_objectid(&item->key) != key.objectid)
	388	break;
	389	if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
	390	continue;
7f5c1516 CM	391	if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
7f5c1516 CM	392	continue;
e20d96d6	393	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
e20d96d6 CM	394	over = filldir(dirent, (const char *)(di + 1),
	395	btrfs_dir_name_len(di),
	396	btrfs_disk_key_offset(&item->key),
	397	btrfs_dir_objectid(di), d_type);
7f5c1516 CM	398	if (over) {
7f5c1516 CM	399	filp->f_pos = btrfs_disk_key_offset(&item->key);
e20d96d6	400	break;
7f5c1516	401	}
e20d96d6 CM	402	filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
e20d96d6 CM	403	}
e20d96d6 CM	404	ret = 0;
	405	err:
	406	btrfs_release_path(root, &path);
	407	return ret;
	408	}
	409
	410	static void btrfs_put_super (struct super_block * sb)
	411	{
	412	struct btrfs_root *root = btrfs_sb(sb);
	413	int ret;
	414
	415	ret = close_ctree(root);
	416	if (ret) {
	417	printk("close ctree returns %d\n", ret);
	418	}
	419	sb->s_fs_info = NULL;
	420	}
2e635a27 CM	421
	422	static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
	423	{
	424	struct inode * inode;
e20d96d6 CM	425	struct dentry * root_dentry;
	426	struct btrfs_super_block *disk_super;
	427	struct buffer_head *bh;
	428	struct btrfs_root *root;
2e635a27 CM	429
	430	sb->s_maxbytes = MAX_LFS_FILESIZE;
	431	sb->s_blocksize = PAGE_CACHE_SIZE;
	432	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	433	sb->s_magic = BTRFS_SUPER_MAGIC;
e20d96d6	434	sb->s_op = &btrfs_super_ops;
2e635a27	435	sb->s_time_gran = 1;
e20d96d6 CM	436
	437	bh = sb_bread(sb, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize);
	438	if (!bh) {
	439	printk("btrfs: unable to read on disk super\n");
	440	return -EIO;
	441	}
	442	disk_super = (struct btrfs_super_block *)bh->b_data;
	443	root = open_ctree(sb, bh, disk_super);
	444	sb->s_fs_info = root;
	445	if (!root) {
	446	printk("btrfs: open_ctree failed\n");
	447	return -EIO;
	448	}
	449	printk("read in super total blocks %Lu root %Lu\n",
	450	btrfs_super_total_blocks(disk_super),
	451	btrfs_super_root_dir(disk_super));
	452
	453	inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
2e635a27 CM	454	if (!inode)
2e635a27 CM	455	return -ENOMEM;
e20d96d6 CM	456	if (inode->i_state & I_NEW) {
	457	btrfs_read_locked_inode(inode);
	458	unlock_new_inode(inode);
	459	}
2e635a27	460
e20d96d6 CM	461	root_dentry = d_alloc_root(inode);
e20d96d6 CM	462	if (!root_dentry) {
2e635a27 CM	463	iput(inode);
	464	return -ENOMEM;
	465	}
e20d96d6 CM	466	sb->s_root = root_dentry;
e20d96d6 CM	467
2e635a27 CM	468	return 0;
	469	}
	470
d5719762 CM	471	static void fill_inode_item(struct btrfs_inode_item *item,
	472	struct inode *inode)
	473	{
	474	btrfs_set_inode_uid(item, inode->i_uid);
	475	btrfs_set_inode_gid(item, inode->i_gid);
	476	btrfs_set_inode_size(item, inode->i_size);
	477	btrfs_set_inode_mode(item, inode->i_mode);
	478	btrfs_set_inode_nlink(item, inode->i_nlink);
	479	btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
	480	btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
	481	btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
	482	btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
	483	btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
	484	btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
	485	btrfs_set_inode_nblocks(item, inode->i_blocks);
	486	btrfs_set_inode_generation(item, inode->i_generation);
	487	}
	488
	489	static struct inode btrfs_new_inode(struct btrfs_trans_handle trans,
	490	struct inode *dir, int mode)
	491	{
	492	struct inode *inode;
	493	struct btrfs_inode_item inode_item;
	494	struct btrfs_root *root = btrfs_sb(dir->i_sb);
	495	struct btrfs_key key;
	496	int ret;
	497	u64 objectid;
	498
	499	inode = new_inode(dir->i_sb);
	500	if (!inode)
	501	return ERR_PTR(-ENOMEM);
	502
	503	ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
	504	BUG_ON(ret);
	505
	506	inode->i_uid = current->fsuid;
	507	inode->i_gid = current->fsgid;
	508	inode->i_mode = mode;
	509	inode->i_ino = objectid;
	510	inode->i_blocks = 0;
	511	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
	512	fill_inode_item(&inode_item, inode);
	513
	514
	515	key.objectid = objectid;
	516	key.flags = 0;
	517	key.offset = 0;
	518	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
	519	ret = btrfs_insert_inode_map(trans, root, objectid, &key);
	520	BUG_ON(ret);
	521
	522	ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
	523	BUG_ON(ret);
	524
	525	insert_inode_hash(inode);
	526	// FIXME mark_inode_dirty(inode)
	527	return inode;
	528	}
	529
	530	static int btrfs_add_link(struct btrfs_trans_handle *trans,
	531	struct dentry dentry, struct inode inode)
	532	{
	533	int ret;
	534	ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
535	dentry->d_name.name, dentry->d_name.len,
536	dentry->d_parent->d_inode->i_ino,
537	inode->i_ino, 0);
d5719762 CM	538	return ret;
	539	}
	540
	541	static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
	542	struct dentry dentry, struct inode inode)
	543	{
	544	int err = btrfs_add_link(trans, dentry, inode);
	545	if (!err) {
	546	d_instantiate(dentry, inode);
	547	return 0;
	548	}
d5719762 CM	549	return err;
	550	}
	551
	552	static int btrfs_create(struct inode dir, struct dentry dentry,
	553	int mode, struct nameidata *nd)
	554	{
	555	struct btrfs_trans_handle *trans;
	556	struct btrfs_root *root = btrfs_sb(dir->i_sb);
	557	struct inode *inode;
	558	int err;
134e9731	559	int drop_inode = 0;
d5719762	560
d561c025	561	mutex_lock(&root->fs_info->fs_mutex);
d5719762 CM	562	trans = btrfs_start_transaction(root, 1);
	563	inode = btrfs_new_inode(trans, dir, mode);
	564	err = PTR_ERR(inode);
	565	if (IS_ERR(inode))
d561c025	566	goto out_unlock;
d5719762 CM	567	// FIXME mark the inode dirty
d5719762 CM	568	err = btrfs_add_nondir(trans, dentry, inode);
134e9731 CM	569	if (err)
134e9731 CM	570	drop_inode = 1;
d5719762 CM	571	dir->i_sb->s_dirt = 1;
d5719762 CM	572	btrfs_end_transaction(trans, root);
d561c025 CM	573	out_unlock:
d561c025 CM	574	mutex_unlock(&root->fs_info->fs_mutex);
134e9731 CM	575	if (drop_inode) {
	576	inode_dec_link_count(inode);
	577	iput(inode);
	578	}
d5719762 CM	579	return err;
	580	}
	581
d5719762 CM	582	static int btrfs_sync_fs(struct super_block *sb, int wait)
	583	{
	584	struct btrfs_trans_handle *trans;
	585	struct btrfs_root *root;
	586	int ret;
df2ce34c	587
d5719762	588	sb->s_dirt = 0;
d561c025 CM	589	if (!wait) {
	590	filemap_flush(sb->s_bdev->bd_inode->i_mapping);
	591	return 0;
	592	}
	593	filemap_write_and_wait(sb->s_bdev->bd_inode->i_mapping);
df2ce34c	594
d5719762	595	root = btrfs_sb(sb);
d561c025	596	mutex_lock(&root->fs_info->fs_mutex);
d5719762 CM	597	trans = btrfs_start_transaction(root, 1);
	598	ret = btrfs_commit_transaction(trans, root);
	599	sb->s_dirt = 0;
	600	BUG_ON(ret);
	601	printk("btrfs sync_fs\n");
d561c025	602	mutex_unlock(&root->fs_info->fs_mutex);
d5719762 CM	603	return 0;
	604	}
	605
d561c025 CM	606	static void btrfs_write_super(struct super_block *sb)
	607	{
	608	btrfs_sync_fs(sb, 1);
	609	}
	610
	611
2e635a27 CM	612	static int btrfs_get_sb(struct file_system_type *fs_type,
	613	int flags, const char dev_name, void data, struct vfsmount *mnt)
	614	{
	615	return get_sb_bdev(fs_type, flags, dev_name, data,
	616	btrfs_fill_super, mnt);
	617	}
	618
	619	static struct file_system_type btrfs_fs_type = {
	620	.owner = THIS_MODULE,
	621	.name = "btrfs",
	622	.get_sb = btrfs_get_sb,
	623	.kill_sb = kill_block_super,
	624	.fs_flags = FS_REQUIRES_DEV,
	625	};
	626
e20d96d6 CM	627	static struct super_operations btrfs_super_ops = {
e20d96d6 CM	628	.statfs = simple_statfs,
134e9731	629	.delete_inode = btrfs_delete_inode,
e20d96d6 CM	630	.put_super = btrfs_put_super,
e20d96d6 CM	631	.read_inode = btrfs_read_locked_inode,
d5719762 CM	632	.write_super = btrfs_write_super,
d5719762 CM	633	.sync_fs = btrfs_sync_fs,
e20d96d6 CM	634	};
	635
	636	static struct inode_operations btrfs_dir_inode_operations = {
	637	.lookup = btrfs_lookup,
d5719762	638	.create = btrfs_create,
134e9731	639	.unlink = btrfs_unlink,
e20d96d6 CM	640	};
	641
	642	static struct file_operations btrfs_dir_file_operations = {
	643	.llseek = generic_file_llseek,
	644	.read = generic_read_dir,
	645	.readdir = btrfs_readdir,
	646	};
	647
	648
2e635a27 CM	649	static int __init init_btrfs_fs(void)
	650	{
	651	printk("btrfs loaded!\n");
	652	return register_filesystem(&btrfs_fs_type);
	653	}
	654
	655	static void __exit exit_btrfs_fs(void)
	656	{
	657	unregister_filesystem(&btrfs_fs_type);
	658	printk("btrfs unloaded\n");
	659	}
	660
	661	module_init(init_btrfs_fs)
	662	module_exit(exit_btrfs_fs)
	663
	664	MODULE_LICENSE("GPL");