[mirror_ubuntu-jammy-kernel.git] / fs / btrfs / export.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/fs.h>
#include <linux/types.h>
#include "ctree.h"
#include "disk-io.h"
#include "btrfs_inode.h"
#include "print-tree.h"
#include "export.h"

#define BTRFS_FID_SIZE_NON_CONNECTABLE (offsetof(struct btrfs_fid, \
						 parent_objectid) / 4)
#define BTRFS_FID_SIZE_CONNECTABLE (offsetof(struct btrfs_fid, \
					     parent_root_objectid) / 4)
#define BTRFS_FID_SIZE_CONNECTABLE_ROOT (sizeof(struct btrfs_fid) / 4)

static int btrfs_encode_fh(struct inode *inode, u32 *fh, int *max_len,
			   struct inode *parent)
{
	struct btrfs_fid *fid = (struct btrfs_fid *)fh;
	int len = *max_len;
	int type;

	if (parent && (len < BTRFS_FID_SIZE_CONNECTABLE)) {
		*max_len = BTRFS_FID_SIZE_CONNECTABLE;
		return FILEID_INVALID;
	} else if (len < BTRFS_FID_SIZE_NON_CONNECTABLE) {
		*max_len = BTRFS_FID_SIZE_NON_CONNECTABLE;
		return FILEID_INVALID;
	}

	len  = BTRFS_FID_SIZE_NON_CONNECTABLE;
	type = FILEID_BTRFS_WITHOUT_PARENT;

	fid->objectid = btrfs_ino(BTRFS_I(inode));
	fid->root_objectid = BTRFS_I(inode)->root->root_key.objectid;
	fid->gen = inode->i_generation;

	if (parent) {
		u64 parent_root_id;

		fid->parent_objectid = BTRFS_I(parent)->location.objectid;
		fid->parent_gen = parent->i_generation;
		parent_root_id = BTRFS_I(parent)->root->root_key.objectid;

		if (parent_root_id != fid->root_objectid) {
			fid->parent_root_objectid = parent_root_id;
			len = BTRFS_FID_SIZE_CONNECTABLE_ROOT;
			type = FILEID_BTRFS_WITH_PARENT_ROOT;
		} else {
			len = BTRFS_FID_SIZE_CONNECTABLE;
			type = FILEID_BTRFS_WITH_PARENT;
		}
	}

	*max_len = len;
	return type;
}

static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
				       u64 root_objectid, u32 generation,
				       int check_generation)
{
	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
	struct btrfs_root *root;
	struct inode *inode;
	struct btrfs_key key;
	int index;
	int err = 0;

	if (objectid < BTRFS_FIRST_FREE_OBJECTID)
		return ERR_PTR(-ESTALE);

	key.objectid = root_objectid;
	key.type = BTRFS_ROOT_ITEM_KEY;
	key.offset = (u64)-1;

	index = srcu_read_lock(&fs_info->subvol_srcu);

	root = btrfs_read_fs_root_no_name(fs_info, &key);
	if (IS_ERR(root)) {
		err = PTR_ERR(root);
		goto fail;
	}

	key.objectid = objectid;
	key.type = BTRFS_INODE_ITEM_KEY;
	key.offset = 0;

	inode = btrfs_iget(sb, &key, root);
	if (IS_ERR(inode)) {
		err = PTR_ERR(inode);
		goto fail;
	}

	srcu_read_unlock(&fs_info->subvol_srcu, index);

	if (check_generation && generation != inode->i_generation) {
		iput(inode);
		return ERR_PTR(-ESTALE);
	}

	return d_obtain_alias(inode);
fail:
	srcu_read_unlock(&fs_info->subvol_srcu, index);
	return ERR_PTR(err);
}

static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh,
					 int fh_len, int fh_type)
{
	struct btrfs_fid *fid = (struct btrfs_fid *) fh;
	u64 objectid, root_objectid;
	u32 generation;

	if (fh_type == FILEID_BTRFS_WITH_PARENT) {
		if (fh_len <  BTRFS_FID_SIZE_CONNECTABLE)
			return NULL;
		root_objectid = fid->root_objectid;
	} else if (fh_type == FILEID_BTRFS_WITH_PARENT_ROOT) {
		if (fh_len < BTRFS_FID_SIZE_CONNECTABLE_ROOT)
			return NULL;
		root_objectid = fid->parent_root_objectid;
	} else
		return NULL;

	objectid = fid->parent_objectid;
	generation = fid->parent_gen;

	return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1);
}

static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh,
					 int fh_len, int fh_type)
{
	struct btrfs_fid *fid = (struct btrfs_fid *) fh;
	u64 objectid, root_objectid;
	u32 generation;

	if ((fh_type != FILEID_BTRFS_WITH_PARENT ||
	     fh_len < BTRFS_FID_SIZE_CONNECTABLE) &&
	    (fh_type != FILEID_BTRFS_WITH_PARENT_ROOT ||
	     fh_len < BTRFS_FID_SIZE_CONNECTABLE_ROOT) &&
	    (fh_type != FILEID_BTRFS_WITHOUT_PARENT ||
	     fh_len < BTRFS_FID_SIZE_NON_CONNECTABLE))
		return NULL;

	objectid = fid->objectid;
	root_objectid = fid->root_objectid;
	generation = fid->gen;

	return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1);
}

static struct dentry *btrfs_get_parent(struct dentry *child)
{
	struct inode *dir = d_inode(child);
	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
	struct btrfs_root *root = BTRFS_I(dir)->root;
	struct btrfs_path *path;
	struct extent_buffer *leaf;
	struct btrfs_root_ref *ref;
	struct btrfs_key key;
	struct btrfs_key found_key;
	int ret;

	path = btrfs_alloc_path();
	if (!path)
		return ERR_PTR(-ENOMEM);

	if (btrfs_ino(BTRFS_I(dir)) == BTRFS_FIRST_FREE_OBJECTID) {
		key.objectid = root->root_key.objectid;
		key.type = BTRFS_ROOT_BACKREF_KEY;
		key.offset = (u64)-1;
		root = fs_info->tree_root;
	} else {
		key.objectid = btrfs_ino(BTRFS_I(dir));
		key.type = BTRFS_INODE_REF_KEY;
		key.offset = (u64)-1;
	}

	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
	if (ret < 0)
		goto fail;

	BUG_ON(ret == 0); /* Key with offset of -1 found */
	if (path->slots[0] == 0) {
		ret = -ENOENT;
		goto fail;
	}

	path->slots[0]--;
	leaf = path->nodes[0];

	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
	if (found_key.objectid != key.objectid || found_key.type != key.type) {
		ret = -ENOENT;
		goto fail;
	}

	if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
		ref = btrfs_item_ptr(leaf, path->slots[0],
				     struct btrfs_root_ref);
		key.objectid = btrfs_root_ref_dirid(leaf, ref);
	} else {
		key.objectid = found_key.offset;
	}
	btrfs_free_path(path);

	if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
		return btrfs_get_dentry(fs_info->sb, key.objectid,
					found_key.offset, 0, 0);
	}

	key.type = BTRFS_INODE_ITEM_KEY;
	key.offset = 0;
	return d_obtain_alias(btrfs_iget(fs_info->sb, &key, root));
fail:
	btrfs_free_path(path);
	return ERR_PTR(ret);
}

static int btrfs_get_name(struct dentry *parent, char *name,
			  struct dentry *child)
{
	struct inode *inode = d_inode(child);
	struct inode *dir = d_inode(parent);
	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
	struct btrfs_path *path;
	struct btrfs_root *root = BTRFS_I(dir)->root;
	struct btrfs_inode_ref *iref;
	struct btrfs_root_ref *rref;
	struct extent_buffer *leaf;
	unsigned long name_ptr;
	struct btrfs_key key;
	int name_len;
	int ret;
	u64 ino;

	if (!S_ISDIR(dir->i_mode))
		return -EINVAL;

	ino = btrfs_ino(BTRFS_I(inode));

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;
	path->leave_spinning = 1;

	if (ino == BTRFS_FIRST_FREE_OBJECTID) {
		key.objectid = BTRFS_I(inode)->root->root_key.objectid;
		key.type = BTRFS_ROOT_BACKREF_KEY;
		key.offset = (u64)-1;
		root = fs_info->tree_root;
	} else {
		key.objectid = ino;
		key.offset = btrfs_ino(BTRFS_I(dir));
		key.type = BTRFS_INODE_REF_KEY;
	}

	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
	if (ret < 0) {
		btrfs_free_path(path);
		return ret;
	} else if (ret > 0) {
		if (ino == BTRFS_FIRST_FREE_OBJECTID) {
			path->slots[0]--;
		} else {
			btrfs_free_path(path);
			return -ENOENT;
		}
	}
	leaf = path->nodes[0];

	if (ino == BTRFS_FIRST_FREE_OBJECTID) {
		rref = btrfs_item_ptr(leaf, path->slots[0],
				     struct btrfs_root_ref);
		name_ptr = (unsigned long)(rref + 1);
		name_len = btrfs_root_ref_name_len(leaf, rref);
	} else {
		iref = btrfs_item_ptr(leaf, path->slots[0],
				      struct btrfs_inode_ref);
		name_ptr = (unsigned long)(iref + 1);
		name_len = btrfs_inode_ref_name_len(leaf, iref);
	}

	read_extent_buffer(leaf, name, name_ptr, name_len);
	btrfs_free_path(path);

	/*
	 * have to add the null termination to make sure that reconnect_path
	 * gets the right len for strlen
	 */
	name[name_len] = '\0';

	return 0;
}

const struct export_operations btrfs_export_ops = {
	.encode_fh	= btrfs_encode_fh,
	.fh_to_dentry	= btrfs_fh_to_dentry,
	.fh_to_parent	= btrfs_fh_to_parent,
	.get_parent	= btrfs_get_parent,
	.get_name	= btrfs_get_name,
};
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
c1d7c514	2
be6e8dc0 BR	3	#include <linux/fs.h>
	4	#include <linux/types.h>
	5	#include "ctree.h"
	6	#include "disk-io.h"
	7	#include "btrfs_inode.h"
	8	#include "print-tree.h"
	9	#include "export.h"
be6e8dc0	10
d397712b CM	11	#define BTRFS_FID_SIZE_NON_CONNECTABLE (offsetof(struct btrfs_fid, \
	12	parent_objectid) / 4)
	13	#define BTRFS_FID_SIZE_CONNECTABLE (offsetof(struct btrfs_fid, \
	14	parent_root_objectid) / 4)
	15	#define BTRFS_FID_SIZE_CONNECTABLE_ROOT (sizeof(struct btrfs_fid) / 4)
be6e8dc0	16
b0b0382b AV	17	static int btrfs_encode_fh(struct inode inode, u32 fh, int *max_len,
b0b0382b AV	18	struct inode *parent)
be6e8dc0 BR	19	{
be6e8dc0 BR	20	struct btrfs_fid fid = (struct btrfs_fid )fh;
be6e8dc0 BR	21	int len = *max_len;
	22	int type;
	23
b0b0382b	24	if (parent && (len < BTRFS_FID_SIZE_CONNECTABLE)) {
5fe0c237	25	*max_len = BTRFS_FID_SIZE_CONNECTABLE;
94e07a75	26	return FILEID_INVALID;
5fe0c237 AK	27	} else if (len < BTRFS_FID_SIZE_NON_CONNECTABLE) {
5fe0c237 AK	28	*max_len = BTRFS_FID_SIZE_NON_CONNECTABLE;
94e07a75	29	return FILEID_INVALID;
5fe0c237	30	}
be6e8dc0 BR	31
	32	len = BTRFS_FID_SIZE_NON_CONNECTABLE;
	33	type = FILEID_BTRFS_WITHOUT_PARENT;
	34
4a0cc7ca	35	fid->objectid = btrfs_ino(BTRFS_I(inode));
4fd786e6	36	fid->root_objectid = BTRFS_I(inode)->root->root_key.objectid;
be6e8dc0 BR	37	fid->gen = inode->i_generation;
be6e8dc0 BR	38
b0b0382b	39	if (parent) {
be6e8dc0 BR	40	u64 parent_root_id;
be6e8dc0 BR	41
be6e8dc0 BR	42	fid->parent_objectid = BTRFS_I(parent)->location.objectid;
be6e8dc0 BR	43	fid->parent_gen = parent->i_generation;
4fd786e6	44	parent_root_id = BTRFS_I(parent)->root->root_key.objectid;
be6e8dc0	45
be6e8dc0 BR	46	if (parent_root_id != fid->root_objectid) {
	47	fid->parent_root_objectid = parent_root_id;
	48	len = BTRFS_FID_SIZE_CONNECTABLE_ROOT;
	49	type = FILEID_BTRFS_WITH_PARENT_ROOT;
	50	} else {
	51	len = BTRFS_FID_SIZE_CONNECTABLE;
	52	type = FILEID_BTRFS_WITH_PARENT;
	53	}
	54	}
	55
	56	*max_len = len;
	57	return type;
	58	}
	59
	60	static struct dentry btrfs_get_dentry(struct super_block sb, u64 objectid,
76dda93c YZ	61	u64 root_objectid, u32 generation,
76dda93c YZ	62	int check_generation)
be6e8dc0	63	{
815745cf	64	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
be6e8dc0 BR	65	struct btrfs_root *root;
be6e8dc0 BR	66	struct inode *inode;
be6e8dc0	67	struct btrfs_key key;
76dda93c YZ	68	int index;
	69	int err = 0;
	70
	71	if (objectid < BTRFS_FIRST_FREE_OBJECTID)
	72	return ERR_PTR(-ESTALE);
be6e8dc0	73
2d4d9fbd	74	key.objectid = root_objectid;
962a298f	75	key.type = BTRFS_ROOT_ITEM_KEY;
2d4d9fbd DW	76	key.offset = (u64)-1;
2d4d9fbd DW	77
76dda93c YZ	78	index = srcu_read_lock(&fs_info->subvol_srcu);
	79
	80	root = btrfs_read_fs_root_no_name(fs_info, &key);
	81	if (IS_ERR(root)) {
	82	err = PTR_ERR(root);
	83	goto fail;
	84	}
	85
be6e8dc0	86	key.objectid = objectid;
962a298f	87	key.type = BTRFS_INODE_ITEM_KEY;
be6e8dc0 BR	88	key.offset = 0;
be6e8dc0 BR	89
4c66e0d4	90	inode = btrfs_iget(sb, &key, root);
76dda93c YZ	91	if (IS_ERR(inode)) {
	92	err = PTR_ERR(inode);
	93	goto fail;
	94	}
	95
	96	srcu_read_unlock(&fs_info->subvol_srcu, index);
be6e8dc0	97
76dda93c	98	if (check_generation && generation != inode->i_generation) {
be6e8dc0 BR	99	iput(inode);
	100	return ERR_PTR(-ESTALE);
	101	}
	102
af53d29a	103	return d_obtain_alias(inode);
76dda93c YZ	104	fail:
	105	srcu_read_unlock(&fs_info->subvol_srcu, index);
	106	return ERR_PTR(err);
be6e8dc0 BR	107	}
	108
	109	static struct dentry btrfs_fh_to_parent(struct super_block sb, struct fid *fh,
	110	int fh_len, int fh_type)
	111	{
	112	struct btrfs_fid fid = (struct btrfs_fid ) fh;
	113	u64 objectid, root_objectid;
	114	u32 generation;
	115
	116	if (fh_type == FILEID_BTRFS_WITH_PARENT) {
7d35199e	117	if (fh_len < BTRFS_FID_SIZE_CONNECTABLE)
be6e8dc0 BR	118	return NULL;
	119	root_objectid = fid->root_objectid;
	120	} else if (fh_type == FILEID_BTRFS_WITH_PARENT_ROOT) {
7d35199e	121	if (fh_len < BTRFS_FID_SIZE_CONNECTABLE_ROOT)
be6e8dc0 BR	122	return NULL;
	123	root_objectid = fid->parent_root_objectid;
	124	} else
	125	return NULL;
	126
	127	objectid = fid->parent_objectid;
	128	generation = fid->parent_gen;
	129
76dda93c	130	return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1);
be6e8dc0 BR	131	}
	132
	133	static struct dentry btrfs_fh_to_dentry(struct super_block sb, struct fid *fh,
	134	int fh_len, int fh_type)
	135	{
	136	struct btrfs_fid fid = (struct btrfs_fid ) fh;
	137	u64 objectid, root_objectid;
	138	u32 generation;
	139
	140	if ((fh_type != FILEID_BTRFS_WITH_PARENT \|\|
7d35199e	141	fh_len < BTRFS_FID_SIZE_CONNECTABLE) &&
be6e8dc0	142	(fh_type != FILEID_BTRFS_WITH_PARENT_ROOT \|\|
7d35199e	143	fh_len < BTRFS_FID_SIZE_CONNECTABLE_ROOT) &&
be6e8dc0	144	(fh_type != FILEID_BTRFS_WITHOUT_PARENT \|\|
7d35199e	145	fh_len < BTRFS_FID_SIZE_NON_CONNECTABLE))
be6e8dc0 BR	146	return NULL;
	147
	148	objectid = fid->objectid;
	149	root_objectid = fid->root_objectid;
	150	generation = fid->gen;
	151
76dda93c	152	return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1);
be6e8dc0 BR	153	}
	154
	155	static struct dentry btrfs_get_parent(struct dentry child)
	156	{
2b0143b5	157	struct inode *dir = d_inode(child);
0b246afa	158	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
be6e8dc0	159	struct btrfs_root *root = BTRFS_I(dir)->root;
be6e8dc0 BR	160	struct btrfs_path *path;
be6e8dc0 BR	161	struct extent_buffer *leaf;
76dda93c YZ	162	struct btrfs_root_ref *ref;
	163	struct btrfs_key key;
	164	struct btrfs_key found_key;
be6e8dc0 BR	165	int ret;
	166
	167	path = btrfs_alloc_path();
2a29edc6	168	if (!path)
2a29edc6	169	return ERR_PTR(-ENOMEM);
be6e8dc0	170
4a0cc7ca	171	if (btrfs_ino(BTRFS_I(dir)) == BTRFS_FIRST_FREE_OBJECTID) {
76dda93c YZ	172	key.objectid = root->root_key.objectid;
	173	key.type = BTRFS_ROOT_BACKREF_KEY;
	174	key.offset = (u64)-1;
0b246afa	175	root = fs_info->tree_root;
76dda93c	176	} else {
4a0cc7ca	177	key.objectid = btrfs_ino(BTRFS_I(dir));
76dda93c YZ	178	key.type = BTRFS_INODE_REF_KEY;
	179	key.offset = (u64)-1;
	180	}
be6e8dc0	181
87acb4ef	182	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
76dda93c YZ	183	if (ret < 0)
	184	goto fail;
	185
79787eaa	186	BUG_ON(ret == 0); /* Key with offset of -1 found */
76dda93c YZ	187	if (path->slots[0] == 0) {
	188	ret = -ENOENT;
	189	goto fail;
d54a8390	190	}
76dda93c YZ	191
76dda93c YZ	192	path->slots[0]--;
be6e8dc0	193	leaf = path->nodes[0];
76dda93c YZ	194
	195	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
	196	if (found_key.objectid != key.objectid \|\| found_key.type != key.type) {
	197	ret = -ENOENT;
	198	goto fail;
be6e8dc0 BR	199	}
be6e8dc0 BR	200
76dda93c YZ	201	if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
	202	ref = btrfs_item_ptr(leaf, path->slots[0],
	203	struct btrfs_root_ref);
	204	key.objectid = btrfs_root_ref_dirid(leaf, ref);
	205	} else {
	206	key.objectid = found_key.offset;
	207	}
be6e8dc0 BR	208	btrfs_free_path(path);
be6e8dc0 BR	209
76dda93c	210	if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
0b246afa	211	return btrfs_get_dentry(fs_info->sb, key.objectid,
76dda93c YZ	212	found_key.offset, 0, 0);
76dda93c YZ	213	}
2d4d9fbd	214
76dda93c	215	key.type = BTRFS_INODE_ITEM_KEY;
be6e8dc0	216	key.offset = 0;
4c66e0d4	217	return d_obtain_alias(btrfs_iget(fs_info->sb, &key, root));
76dda93c YZ	218	fail:
	219	btrfs_free_path(path);
	220	return ERR_PTR(ret);
be6e8dc0 BR	221	}
be6e8dc0 BR	222
2ede0daf JB	223	static int btrfs_get_name(struct dentry parent, char name,
	224	struct dentry *child)
	225	{
2b0143b5 DH	226	struct inode *inode = d_inode(child);
2b0143b5 DH	227	struct inode *dir = d_inode(parent);
0b246afa	228	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2ede0daf JB	229	struct btrfs_path *path;
	230	struct btrfs_root *root = BTRFS_I(dir)->root;
	231	struct btrfs_inode_ref *iref;
	232	struct btrfs_root_ref *rref;
	233	struct extent_buffer *leaf;
	234	unsigned long name_ptr;
	235	struct btrfs_key key;
	236	int name_len;
	237	int ret;
33345d01	238	u64 ino;
2ede0daf	239
2ede0daf JB	240	if (!S_ISDIR(dir->i_mode))
	241	return -EINVAL;
	242
4a0cc7ca	243	ino = btrfs_ino(BTRFS_I(inode));
33345d01	244
2ede0daf JB	245	path = btrfs_alloc_path();
	246	if (!path)
	247	return -ENOMEM;
	248	path->leave_spinning = 1;
	249
33345d01	250	if (ino == BTRFS_FIRST_FREE_OBJECTID) {
2ede0daf JB	251	key.objectid = BTRFS_I(inode)->root->root_key.objectid;
	252	key.type = BTRFS_ROOT_BACKREF_KEY;
	253	key.offset = (u64)-1;
0b246afa	254	root = fs_info->tree_root;
2ede0daf	255	} else {
33345d01	256	key.objectid = ino;
4a0cc7ca	257	key.offset = btrfs_ino(BTRFS_I(dir));
2ede0daf JB	258	key.type = BTRFS_INODE_REF_KEY;
	259	}
	260
	261	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
	262	if (ret < 0) {
	263	btrfs_free_path(path);
	264	return ret;
	265	} else if (ret > 0) {
33345d01	266	if (ino == BTRFS_FIRST_FREE_OBJECTID) {
2ede0daf JB	267	path->slots[0]--;
	268	} else {
	269	btrfs_free_path(path);
	270	return -ENOENT;
	271	}
	272	}
	273	leaf = path->nodes[0];
	274
33345d01 LZ	275	if (ino == BTRFS_FIRST_FREE_OBJECTID) {
33345d01 LZ	276	rref = btrfs_item_ptr(leaf, path->slots[0],
2ede0daf	277	struct btrfs_root_ref);
33345d01 LZ	278	name_ptr = (unsigned long)(rref + 1);
33345d01 LZ	279	name_len = btrfs_root_ref_name_len(leaf, rref);
2ede0daf JB	280	} else {
	281	iref = btrfs_item_ptr(leaf, path->slots[0],
	282	struct btrfs_inode_ref);
	283	name_ptr = (unsigned long)(iref + 1);
	284	name_len = btrfs_inode_ref_name_len(leaf, iref);
	285	}
	286
	287	read_extent_buffer(leaf, name, name_ptr, name_len);
	288	btrfs_free_path(path);
	289
	290	/*
	291	* have to add the null termination to make sure that reconnect_path
	292	* gets the right len for strlen
	293	*/
	294	name[name_len] = '\0';
	295
	296	return 0;
	297	}
	298
be6e8dc0 BR	299	const struct export_operations btrfs_export_ops = {
	300	.encode_fh = btrfs_encode_fh,
	301	.fh_to_dentry = btrfs_fh_to_dentry,
	302	.fh_to_parent = btrfs_fh_to_parent,
	303	.get_parent = btrfs_get_parent,
2ede0daf	304	.get_name = btrfs_get_name,
be6e8dc0	305	};