[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"

#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);
		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_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) {
		*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;

	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 = filp->f_pos > 0 && ret != 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];
			} 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;
		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)
			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 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,
	.drop_inode	= generic_delete_inode,
	.put_super	= btrfs_put_super,
	.read_inode	= btrfs_read_locked_inode,
};

static struct inode_operations btrfs_dir_inode_operations = {
	.lookup		= btrfs_lookup,
};

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"
2e635a27 CM	13
2e635a27 CM	14	#define BTRFS_SUPER_MAGIC 0x9123682E
e20d96d6 CM	15
	16	static struct inode_operations btrfs_dir_inode_operations;
	17	static struct super_operations btrfs_super_ops;
	18	static struct file_operations btrfs_dir_file_operations;
	19
2e635a27 CM	20	#if 0
	21	/* some random number */
	22
	23	static struct super_operations ramfs_ops;
2e635a27 CM	24
	25	static struct backing_dev_info ramfs_backing_dev_info = {
	26	.ra_pages = 0, /* No readahead */
	27	.capabilities = BDI_CAP_NO_ACCT_DIRTY \| BDI_CAP_NO_WRITEBACK \|
	28	BDI_CAP_MAP_DIRECT \| BDI_CAP_MAP_COPY \|
	29	BDI_CAP_READ_MAP \| BDI_CAP_WRITE_MAP \| BDI_CAP_EXEC_MAP,
	30	};
	31
	32	struct inode ramfs_get_inode(struct super_block sb, int mode, dev_t dev)
	33	{
	34	struct inode * inode = new_inode(sb);
	35
	36	if (inode) {
	37	inode->i_mode = mode;
	38	inode->i_uid = current->fsuid;
	39	inode->i_gid = current->fsgid;
	40	inode->i_blocks = 0;
	41	inode->i_mapping->a_ops = &ramfs_aops;
	42	inode->i_mapping->backing_dev_info = &ramfs_backing_dev_info;
	43	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	44	switch (mode & S_IFMT) {
	45	default:
	46	init_special_inode(inode, mode, dev);
	47	break;
	48	case S_IFREG:
	49	inode->i_op = &ramfs_file_inode_operations;
	50	inode->i_fop = &ramfs_file_operations;
	51	break;
	52	case S_IFDIR:
	53	inode->i_op = &ramfs_dir_inode_operations;
	54	inode->i_fop = &simple_dir_operations;
	55
	56	/* directory inodes start off with i_nlink == 2 (for "." entry) */
	57	inc_nlink(inode);
	58	break;
	59	case S_IFLNK:
	60	inode->i_op = &page_symlink_inode_operations;
	61	break;
	62	}
	63	}
	64	return inode;
	65	}
	66
	67	/*
	68	* File creation. Allocate an inode, and we're done..
	69	*/
	70	/* SMP-safe */
	71	static int
	72	ramfs_mknod(struct inode dir, struct dentry dentry, int mode, dev_t dev)
	73	{
	74	struct inode * inode = ramfs_get_inode(dir->i_sb, mode, dev);
	75	int error = -ENOSPC;
	76
	77	if (inode) {
	78	if (dir->i_mode & S_ISGID) {
	79	inode->i_gid = dir->i_gid;
	80	if (S_ISDIR(mode))
	81	inode->i_mode \|= S_ISGID;
	82	}
	83	d_instantiate(dentry, inode);
	84	dget(dentry); /* Extra count - pin the dentry in core */
	85	error = 0;
	86	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
	87	}
88	return error;
89	}
90
91	static int ramfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
92	{
93	int retval = ramfs_mknod(dir, dentry, mode \| S_IFDIR, 0);
94	if (!retval)
95	inc_nlink(dir);
96	return retval;
97	}
98
99	static int ramfs_create(struct inode dir, struct dentry dentry, int mode, struct nameidata *nd)
100	{
101	return ramfs_mknod(dir, dentry, mode \| S_IFREG, 0);
102	}
103
104	static int ramfs_symlink(struct inode * dir, struct dentry dentry, const char symname)
105	{
106	struct inode *inode;
107	int error = -ENOSPC;
108
109	inode = ramfs_get_inode(dir->i_sb, S_IFLNK\|S_IRWXUGO, 0);
110	if (inode) {
111	int l = strlen(symname)+1;
112	error = page_symlink(inode, symname, l);
113	if (!error) {
114	if (dir->i_mode & S_ISGID)
115	inode->i_gid = dir->i_gid;
116	d_instantiate(dentry, inode);
117	dget(dentry);
118	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
119	} else
120	iput(inode);
121	}
122	return error;
123	}
124
125	static struct inode_operations ramfs_dir_inode_operations = {
126	.create = ramfs_create,
127	.lookup = simple_lookup,
128	.link = simple_link,
129	.unlink = simple_unlink,
130	.symlink = ramfs_symlink,
131	.mkdir = ramfs_mkdir,
132	.rmdir = simple_rmdir,
133	.mknod = ramfs_mknod,
134	.rename = simple_rename,
135	};
136	#endif
137
e20d96d6	138	static void btrfs_read_locked_inode(struct inode *inode)
2e635a27	139	{
e20d96d6 CM	140	struct btrfs_path path;
	141	struct btrfs_inode_item *inode_item;
	142	struct btrfs_root *root = btrfs_sb(inode->i_sb);
	143	int ret;
e20d96d6 CM	144	btrfs_init_path(&path);
	145	ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
	146	if (ret) {
	147	make_bad_inode(inode);
	148	return;
	149	}
	150	inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
	151	path.slots[0],
	152	struct btrfs_inode_item);
2e635a27	153
e20d96d6 CM	154	inode->i_mode = btrfs_inode_mode(inode_item);
	155	inode->i_nlink = btrfs_inode_nlink(inode_item);
	156	inode->i_uid = btrfs_inode_uid(inode_item);
	157	inode->i_gid = btrfs_inode_gid(inode_item);
	158	inode->i_size = btrfs_inode_size(inode_item);
	159	inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
	160	inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
	161	inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
	162	inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
	163	inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
	164	inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
	165	inode->i_blocks = btrfs_inode_nblocks(inode_item);
	166	inode->i_generation = btrfs_inode_generation(inode_item);
e20d96d6 CM	167	btrfs_release_path(root, &path);
	168	switch (inode->i_mode & S_IFMT) {
	169	#if 0
	170	default:
	171	init_special_inode(inode, inode->i_mode,
	172	btrfs_inode_rdev(inode_item));
	173	break;
	174	#endif
	175	case S_IFREG:
e20d96d6 CM	176	break;
e20d96d6 CM	177	case S_IFDIR:
e20d96d6 CM	178	inode->i_op = &btrfs_dir_inode_operations;
	179	inode->i_fop = &btrfs_dir_file_operations;
	180	break;
	181	case S_IFLNK:
e20d96d6 CM	182	// inode->i_op = &page_symlink_inode_operations;
e20d96d6 CM	183	break;
2e635a27	184	}
e20d96d6	185	return;
2e635a27 CM	186	}
2e635a27 CM	187
e20d96d6 CM	188	static int btrfs_inode_by_name(struct inode dir, struct dentry dentry,
	189	ino_t *ino)
	190	{
	191	const char *name = dentry->d_name.name;
	192	int namelen = dentry->d_name.len;
	193	struct btrfs_dir_item *di;
	194	struct btrfs_path path;
	195	struct btrfs_root *root = btrfs_sb(dir->i_sb);
	196	int ret;
	197
	198	btrfs_init_path(&path);
	199	ret = btrfs_lookup_dir_item(NULL, root, &path, dir->i_ino, name,
	200	namelen, 0);
	201	if (ret) {
	202	*ino = 0;
	203	goto out;
	204	}
	205	di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
	206	struct btrfs_dir_item);
	207	*ino = btrfs_dir_objectid(di);
	208	out:
	209	btrfs_release_path(root, &path);
	210	return ret;
	211	}
	212
	213	static struct dentry btrfs_lookup(struct inode dir, struct dentry *dentry,
	214	struct nameidata *nd)
	215	{
	216	struct inode * inode;
	217	ino_t ino;
	218	int ret;
	219
	220	if (dentry->d_name.len > BTRFS_NAME_LEN)
	221	return ERR_PTR(-ENAMETOOLONG);
	222
	223	ret = btrfs_inode_by_name(dir, dentry, &ino);
	224	if (ret < 0)
	225	return ERR_PTR(ret);
	226	inode = NULL;
	227	if (ino) {
e20d96d6 CM	228	inode = iget(dir->i_sb, ino);
	229	if (!inode)
	230	return ERR_PTR(-EACCES);
	231	}
	232	return d_splice_alias(inode, dentry);
	233	}
	234
	235	static int btrfs_readdir(struct file filp, void dirent, filldir_t filldir)
	236	{
	237	struct inode *inode = filp->f_path.dentry->d_inode;
	238	struct btrfs_root *root = btrfs_sb(inode->i_sb);
	239	struct btrfs_item *item;
	240	struct btrfs_dir_item *di;
	241	struct btrfs_key key;
	242	struct btrfs_path path;
	243	int ret;
	244	u32 nritems;
	245	struct btrfs_leaf *leaf;
	246	int slot;
	247	int advance;
	248	unsigned char d_type = DT_UNKNOWN;
	249	int over;
	250
	251	key.objectid = inode->i_ino;
e20d96d6 CM	252	key.flags = 0;
	253	btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
	254	key.offset = filp->f_pos;
	255	btrfs_init_path(&path);
	256	ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
	257	if (ret < 0) {
	258	goto err;
	259	}
e20d96d6 CM	260	advance = filp->f_pos > 0 && ret != 0;
	261	while(1) {
	262	leaf = btrfs_buffer_leaf(path.nodes[0]);
	263	nritems = btrfs_header_nritems(&leaf->header);
	264	slot = path.slots[0];
e20d96d6	265	if (advance) {
e20d96d6 CM	266	if (slot == nritems -1) {
	267	ret = btrfs_next_leaf(root, &path);
	268	if (ret)
	269	break;
	270	leaf = btrfs_buffer_leaf(path.nodes[0]);
	271	nritems = btrfs_header_nritems(&leaf->header);
	272	slot = path.slots[0];
e20d96d6 CM	273	} else {
	274	slot++;
	275	path.slots[0]++;
	276	}
	277	}
	278	advance = 1;
	279	item = leaf->items + slot;
e20d96d6 CM	280	if (btrfs_disk_key_objectid(&item->key) != key.objectid)
	281	break;
	282	if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
	283	continue;
	284	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
e20d96d6 CM	285	over = filldir(dirent, (const char *)(di + 1),
	286	btrfs_dir_name_len(di),
	287	btrfs_disk_key_offset(&item->key),
	288	btrfs_dir_objectid(di), d_type);
	289	if (over)
	290	break;
	291	filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
	292	}
e20d96d6 CM	293	ret = 0;
	294	err:
	295	btrfs_release_path(root, &path);
	296	return ret;
	297	}
	298
	299	static void btrfs_put_super (struct super_block * sb)
	300	{
	301	struct btrfs_root *root = btrfs_sb(sb);
	302	int ret;
	303
	304	ret = close_ctree(root);
	305	if (ret) {
	306	printk("close ctree returns %d\n", ret);
	307	}
	308	sb->s_fs_info = NULL;
	309	}
2e635a27 CM	310
	311	static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
	312	{
	313	struct inode * inode;
e20d96d6 CM	314	struct dentry * root_dentry;
	315	struct btrfs_super_block *disk_super;
	316	struct buffer_head *bh;
	317	struct btrfs_root *root;
2e635a27 CM	318
	319	sb->s_maxbytes = MAX_LFS_FILESIZE;
	320	sb->s_blocksize = PAGE_CACHE_SIZE;
	321	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	322	sb->s_magic = BTRFS_SUPER_MAGIC;
e20d96d6	323	sb->s_op = &btrfs_super_ops;
2e635a27	324	sb->s_time_gran = 1;
e20d96d6 CM	325
	326	bh = sb_bread(sb, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize);
	327	if (!bh) {
	328	printk("btrfs: unable to read on disk super\n");
	329	return -EIO;
	330	}
	331	disk_super = (struct btrfs_super_block *)bh->b_data;
	332	root = open_ctree(sb, bh, disk_super);
	333	sb->s_fs_info = root;
	334	if (!root) {
	335	printk("btrfs: open_ctree failed\n");
	336	return -EIO;
	337	}
	338	printk("read in super total blocks %Lu root %Lu\n",
	339	btrfs_super_total_blocks(disk_super),
	340	btrfs_super_root_dir(disk_super));
	341
	342	inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
2e635a27 CM	343	if (!inode)
2e635a27 CM	344	return -ENOMEM;
e20d96d6 CM	345	if (inode->i_state & I_NEW) {
	346	btrfs_read_locked_inode(inode);
	347	unlock_new_inode(inode);
	348	}
2e635a27	349
e20d96d6 CM	350	root_dentry = d_alloc_root(inode);
e20d96d6 CM	351	if (!root_dentry) {
2e635a27 CM	352	iput(inode);
	353	return -ENOMEM;
	354	}
e20d96d6 CM	355	sb->s_root = root_dentry;
e20d96d6 CM	356
2e635a27 CM	357	return 0;
	358	}
	359
	360	static int btrfs_get_sb(struct file_system_type *fs_type,
	361	int flags, const char dev_name, void data, struct vfsmount *mnt)
	362	{
	363	return get_sb_bdev(fs_type, flags, dev_name, data,
	364	btrfs_fill_super, mnt);
	365	}
	366
	367	static struct file_system_type btrfs_fs_type = {
	368	.owner = THIS_MODULE,
	369	.name = "btrfs",
	370	.get_sb = btrfs_get_sb,
	371	.kill_sb = kill_block_super,
	372	.fs_flags = FS_REQUIRES_DEV,
	373	};
	374
e20d96d6 CM	375	static struct super_operations btrfs_super_ops = {
	376	.statfs = simple_statfs,
	377	.drop_inode = generic_delete_inode,
	378	.put_super = btrfs_put_super,
	379	.read_inode = btrfs_read_locked_inode,
	380	};
	381
	382	static struct inode_operations btrfs_dir_inode_operations = {
	383	.lookup = btrfs_lookup,
	384	};
	385
	386	static struct file_operations btrfs_dir_file_operations = {
	387	.llseek = generic_file_llseek,
	388	.read = generic_read_dir,
	389	.readdir = btrfs_readdir,
	390	};
	391
	392
2e635a27 CM	393	static int __init init_btrfs_fs(void)
	394	{
	395	printk("btrfs loaded!\n");
	396	return register_filesystem(&btrfs_fs_type);
	397	}
	398
	399	static void __exit exit_btrfs_fs(void)
	400	{
	401	unregister_filesystem(&btrfs_fs_type);
	402	printk("btrfs unloaded\n");
	403	}
	404
	405	module_init(init_btrfs_fs)
	406	module_exit(exit_btrfs_fs)
	407
	408	MODULE_LICENSE("GPL");