// SPDX-License-Identifier: GPL-2.0-only
/*
* Overlayfs NFS export support.
*
* Amir Goldstein <[email protected]>
*
* Copyright (C) 2017-2018 CTERA Networks. All Rights Reserved.
*/
#include <linux/fs.h>
#include <linux/cred.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/xattr.h>
#include <linux/exportfs.h>
#include <linux/ratelimit.h>
#include "overlayfs.h"
static int ovl_encode_maybe_copy_up(struct dentry *dentry)
{
int err;
if (ovl_dentry_upper(dentry))
return 0;
err = ovl_copy_up(dentry);
if (err) {
pr_warn_ratelimited("failed to copy up on encode (%pd2, err=%i)\n",
dentry, err);
}
return err;
}
/*
* Before encoding a non-upper directory file handle from real layer N, we need
* to check if it will be possible to reconnect an overlay dentry from the real
* lower decoded dentry. This is done by following the overlay ancestry up to a
* "layer N connected" ancestor and verifying that all parents along the way are
* "layer N connectable". If an ancestor that is NOT "layer N connectable" is
* found, we need to copy up an ancestor, which is "layer N connectable", thus
* making that ancestor "layer N connected". For example:
*
* layer 1: /a
* layer 2: /a/b/c
*
* The overlay dentry /a is NOT "layer 2 connectable", because if dir /a is
* copied up and renamed, upper dir /a will be indexed by lower dir /a from
* layer 1. The dir /a from layer 2 will never be indexed, so the algorithm (*)
* in ovl_lookup_real_ancestor() will not be able to lookup a connected overlay
* dentry from the connected lower dentry /a/b/c.
*
* To avoid this problem on decode time, we need to copy up an ancestor of
* /a/b/c, which is "layer 2 connectable", on encode time. That ancestor is
* /a/b. After copy up (and index) of /a/b, it will become "layer 2 connected"
* and when the time comes to decode the file handle from lower dentry /a/b/c,
* ovl_lookup_real_ancestor() will find the indexed ancestor /a/b and decoding
* a connected overlay dentry will be accomplished.
*
* (*) the algorithm in ovl_lookup_real_ancestor() can be improved to lookup an
* entry /a in the lower layers above layer N and find the indexed dir /a from
* layer 1. If that improvement is made, then the check for "layer N connected"
* will need to verify there are no redirects in lower layers above N. In the
* example above, /a will be "layer 2 connectable". However, if layer 2 dir /a
* is a target of a layer 1 redirect, then /a will NOT be "layer 2 connectable":
*
* layer 1: /A (redirect = /a)
* layer 2: /a/b/c
*/
/* Return the lowest layer for encoding a connectable file handle */
static int ovl_connectable_layer(struct dentry *dentry)
{
struct ovl_entry *oe = OVL_E(dentry);
/* We can get overlay root from root of any layer */
if (dentry == dentry->d_sb->s_root)
return ovl_numlower(oe);
/*
* If it's an unindexed merge dir, then it's not connectable with any
* lower layer
*/
if (ovl_dentry_upper(dentry) &&
!ovl_test_flag(OVL_INDEX, d_inode(dentry)))
return 0;
/* We can get upper/overlay path from indexed/lower dentry */
return ovl_lowerstack(oe)->layer->idx;
}
/*
* @dentry is "connected" if all ancestors up to root or a "connected" ancestor
* have the same uppermost lower layer as the origin's layer. We may need to
* copy up a "connectable" ancestor to make it "connected". A "connected" dentry
* cannot become non "connected", so cache positive result in dentry flags.
*
* Return the connected origin layer or < 0 on error.
*/
static int ovl_connect_layer(struct dentry *dentry)
{
struct dentry *next, *parent = NULL;
struct ovl_entry *oe = OVL_E(dentry);
int origin_layer;
int err = 0;
if (WARN_ON(dentry == dentry->d_sb->s_root) ||
WARN_ON(!ovl_dentry_lower(dentry)))
return -EIO;
origin_layer = ovl_lowerstack(oe)->layer->idx;
if (ovl_dentry_test_flag(OVL_E_CONNECTED, dentry))
return origin_layer;
/* Find the topmost origin layer connectable ancestor of @dentry */
next = dget(dentry);
for (;;) {
parent = dget_parent(next);
if (WARN_ON(parent == next)) {
err = -EIO;
break;
}
/*
* If @parent is not origin layer connectable, then copy up
* @next which is origin layer connectable and we are done.
*/
if (ovl_connectable_layer(parent) < origin_layer) {
err = ovl_encode_maybe_copy_up(next);
break;
}
/* If @parent is connected or indexed we are done */
if (ovl_dentry_test_flag(OVL_E_CONNECTED, parent) ||
ovl_test_flag(OVL_INDEX, d_inode(parent)))
break;
dput(next);
next = parent;
}
dput(parent);
dput(next);
if (!err)
ovl_dentry_set_flag(OVL_E_CONNECTED, dentry);
return err ?: origin_layer;
}
/*
* We only need to encode origin if there is a chance that the same object was
* encoded pre copy up and then we need to stay consistent with the same
* encoding also after copy up. If non-pure upper is not indexed, then it was
* copied up before NFS export was enabled. In that case we don't need to worry
* about staying consistent with pre copy up encoding and we encode an upper
* file handle. Overlay root dentry is a private case of non-indexed upper.
*
* The following table summarizes the different file handle encodings used for
* different overlay object types:
*
* Object type | Encoding
* --------------------------------
* Pure upper | U
* Non-indexed upper | U
* Indexed upper | L (*)
* Non-upper | L (*)
*
* U = upper file handle
* L = lower file handle
*
* (*) Decoding a connected overlay dir from real lower dentry is not always
* possible when there are redirects in lower layers and non-indexed merge dirs.
* To mitigate those case, we may copy up the lower dir ancestor before encode
* of a decodable file handle for non-upper dir.
*
* Return 0 for upper file handle, > 0 for lower file handle or < 0 on error.
*/
static int ovl_check_encode_origin(struct dentry *dentry)
{
struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
bool decodable = ofs->config.nfs_export;
/* No upper layer? */
if (!ovl_upper_mnt(ofs))
return 1;
/* Lower file handle for non-upper non-decodable */
if (!ovl_dentry_upper(dentry) && !decodable)
return 1;
/* Upper file handle for pure upper */
if (!ovl_dentry_lower(dentry))
return 0;
/*
* Root is never indexed, so if there's an upper layer, encode upper for
* root.
*/
if (dentry == dentry->d_sb->s_root)
return 0;
/*
* Upper decodable file handle for non-indexed upper.
*/
if (ovl_dentry_upper(dentry) && decodable &&
!ovl_test_flag(OVL_INDEX, d_inode(dentry)))
return 0;
/*
* Decoding a merge dir, whose origin's ancestor is under a redirected
* lower dir or under a non-indexed upper is not always possible.
* ovl_connect_layer() will try to make origin's layer "connected" by
* copying up a "connectable" ancestor.
*/
if (d_is_dir(dentry) && decodable)
return ovl_connect_layer(dentry);
/* Lower file handle for indexed and non-upper dir/non-dir */
return 1;
}
static int ovl_dentry_to_fid(struct ovl_fs *ofs, struct dentry *dentry,
u32 *fid, int buflen)
{
struct ovl_fh *fh = NULL;
int err, enc_lower;
int len;
/*
* Check if we should encode a lower or upper file handle and maybe
* copy up an ancestor to make lower file handle connectable.
*/
err = enc_lower = ovl_check_encode_origin(dentry);
if (enc_lower < 0)
goto fail;
/* Encode an upper or lower file handle */
fh = ovl_encode_real_fh(ofs, enc_lower ? ovl_dentry_lower(dentry) :
ovl_dentry_upper(dentry), !enc_lower);
if (IS_ERR(fh))
return PTR_ERR(fh);
len = OVL_FH_LEN(fh);
if (len <= buflen)
memcpy(fid, fh, len);
err = len;
out:
kfree(fh);
return err;
fail:
pr_warn_ratelimited("failed to encode file handle (%pd2, err=%i)\n",
dentry, err);
goto out;
}
static int ovl_encode_fh(struct inode *inode, u32 *fid, int *max_len,
struct inode *parent)
{
struct ovl_fs *ofs = OVL_FS(inode->i_sb);
struct dentry *dentry;
int bytes, buflen = *max_len << 2;
/* TODO: encode connectable file handles */
if (parent)
return FILEID_INVALID;
dentry = d_find_any_alias(inode);
if (!dentry)
return FILEID_INVALID;
bytes = ovl_dentry_to_fid(ofs, dentry, fid, buflen);
dput(dentry);
if (bytes <= 0)
return FILEID_INVALID;
*max_len = bytes >> 2;
if (bytes > buflen)
return FILEID_INVALID;
return OVL_FILEID_V1;
}
/*
* Find or instantiate an overlay dentry from real dentries and index.
*/
static struct dentry *ovl_obtain_alias(struct super_block *sb,
struct dentry *upper_alias,
struct ovl_path *lowerpath,
struct dentry *index)
{
struct dentry *lower = lowerpath ? lowerpath->dentry : NULL;
struct dentry *upper = upper_alias ?: index;
struct inode *inode = NULL;
struct ovl_entry *oe;
struct ovl_inode_params oip = {
.index = index,
};
/* We get overlay directory dentries with ovl_lookup_real() */
if (d_is_dir(upper ?: lower))
return ERR_PTR(-EIO);
oe = ovl_alloc_entry(!!lower);
if (!oe)
return ERR_PTR(-ENOMEM);
oip.upperdentry = dget(upper);
if (lower) {
ovl_lowerstack(oe)->dentry = dget(lower);
ovl_lowerstack(oe)->layer = lowerpath->layer;
}
oip.oe = oe;
inode = ovl_get_inode(sb, &oip);
if (IS_ERR(inode)) {
ovl_free_entry(oe);
dput(upper);
return ERR_CAST(inode);
}
if (upper)
ovl_set_flag(OVL_UPPERDATA, inode);
return d_obtain_alias(inode);
}
/* Get the upper or lower dentry in stack whose on layer @idx */
static struct dentry *ovl_dentry_real_at(struct dentry *dentry, int idx)
{
struct ovl_entry *oe = OVL_E(dentry);
struct ovl_path *lowerstack = ovl_lowerstack(oe);
int i;
if (!idx)
return ovl_dentry_upper(dentry);
for (i = 0; i < ovl_numlower(oe); i++) {
if (lowerstack[i].layer->idx == idx)
return lowerstack[i].dentry;
}
return NULL;
}
/*
* Lookup a child overlay dentry to get a connected overlay dentry whose real
* dentry is @real. If @real is on upper layer, we lookup a child overlay
* dentry with the same name as the real dentry. Otherwise, we need to consult
* index for lookup.
*/
static struct dentry *ovl_lookup_real_one(struct dentry *connected,
struct dentry *real,
const struct ovl_layer *layer)
{
struct inode *dir = d_inode(connected);
struct dentry *this, *parent = NULL;
struct name_snapshot name;
int err;
/*
* Lookup child overlay dentry by real name. The dir mutex protects us
* from racing with overlay rename. If the overlay dentry that is above
* real has already been moved to a parent that is not under the
* connected overlay dir, we return -ECHILD and restart the lookup of
* connected real path from the top.
*/
inode_lock_nested(dir, I_MUTEX_PARENT);
err = -ECHILD;
parent = dget_parent(real);
if (ovl_dentry_real_at(connected, layer->idx) != parent)
goto fail;
/*
* We also need to take a snapshot of real dentry name to protect us
* from racing with underlying layer rename. In this case, we don't
* care about returning ESTALE, only from dereferencing a free name
* pointer because we hold no lock on the real dentry.
*/
take_dentry_name_snapshot(&name, real);
/*
* No idmap handling here: it's an internal lookup. Could skip
* permission checking altogether, but for now just use non-idmap
* transformed ids.
*/
this = lookup_one_len(name.name.name, connected, name.name.len);
release_dentry_name_snapshot(&name);
err = PTR_ERR(this);
if (IS_ERR(this)) {
goto fail;
} else if (!this || !this->d_inode) {
dput(this);
err = -ENOENT;
goto fail;
} else if (ovl_dentry_real_at(this, layer->idx) != real) {
dput(this);
err = -ESTALE;
goto fail;
}
out:
dput(parent);
inode_unlock(dir);
return this;
fail:
pr_warn_ratelimited("failed to lookup one by real (%pd2, layer=%d, connected=%pd2, err=%i)\n",
real, layer->idx, connected, err);
this = ERR_PTR(err);
goto out;
}
static struct dentry *ovl_lookup_real(struct super_block *sb,
struct dentry *real,
const struct ovl_layer *layer);
/*
* Lookup an indexed or hashed overlay dentry by real inode.
*/
static struct dentry *ovl_lookup_real_inode(struct super_block *sb,
struct dentry *real,
const struct ovl_layer *layer)
{
struct ovl_fs *ofs = OVL_FS(sb);
struct dentry *index = NULL;
struct dentry *this = NULL;
struct inode *inode;
/*
* Decoding upper dir from index is expensive, so first try to lookup
* overlay dentry in inode/dcache.
*/
inode = ovl_lookup_inode(sb, real, !layer->idx);
if (IS_ERR(inode))
return ERR_CAST(inode);
if (inode) {
this = d_find_any_alias(inode);
iput(inode);
}
/*
* For decoded lower dir file handle, lookup index by origin to check
* if lower dir was copied up and and/or removed.
*/
if (!this && layer->idx && ovl_indexdir(sb) && !WARN_ON(!d_is_dir(real))) {
index = ovl_lookup_index(ofs, NULL, real, false);
if (IS_ERR(index))
return index;
}
/* Get connected upper overlay dir from index */
if (index) {
struct dentry *upper = ovl_index_upper(ofs, index, true);
dput(index);
if (IS_ERR_OR_NULL(upper))
return upper;
/*
* ovl_lookup_real() in lower layer may call recursively once to
* ovl_lookup_real() in upper layer. The first level call walks
* back lower parents to the topmost indexed parent. The second
* recursive call walks back from indexed upper to the topmost
* connected/hashed upper parent (or up to root).
*/
this = ovl_lookup_real(sb, upper, &ofs->layers[0]);
dput(upper);
}
if (IS_ERR_OR_NULL(this))
return this;
if (ovl_dentry_real_at(this, layer->idx) != real) {
dput(this);
this = ERR_PTR(-EIO);
}
return this;
}
/*
* Lookup an indexed or hashed overlay dentry, whose real dentry is an
* ancestor of @real.
*/
static struct dentry *ovl_lookup_real_ancestor(struct super_block *sb,
struct dentry *real,
const struct ovl_layer *layer)
{
struct dentry *next, *parent = NULL;
struct dentry *ancestor = ERR_PTR(-EIO);
if (real == layer->mnt->mnt_root)
return dget(sb->s_root);
/* Find the topmost indexed or hashed ancestor */
next = dget(real);
for (;;) {
parent = dget_parent(next);
/*
* Lookup a matching overlay dentry in inode/dentry
* cache or in index by real inode.
*/
ancestor = ovl_lookup_real_inode(sb, next, layer);
if (ancestor)
break;
if (parent == layer->mnt->mnt_root) {
ancestor = dget(sb->s_root);
break;
}
/*
* If @real has been moved out of the layer root directory,
* we will eventully hit the real fs root. This cannot happen
* by legit overlay rename, so we return error in that case.
*/
if (parent == next) {
ancestor = ERR_PTR(-EXDEV);
break;
}
dput(next);
next = parent;
}
dput(parent);
dput(next);
return ancestor;
}
/*
* Lookup a connected overlay dentry whose real dentry is @real.
* If @real is on upper layer, we lookup a child overlay dentry with the same
* path the real dentry. Otherwise, we need to consult index for lookup.
*/
static struct dentry *ovl_lookup_real(struct super_block *sb,
struct dentry *real,
const struct ovl_layer *layer)
{
struct dentry *connected;
int err = 0;
connected = ovl_lookup_real_ancestor(sb, real, layer);
if (IS_ERR(connected))
return connected;
while (!err) {
struct dentry *next, *this;
struct dentry *parent = NULL;
struct dentry *real_connected = ovl_dentry_real_at(connected,
layer->idx);
if (real_connected == real)
break;
/* Find the topmost dentry not yet connected */
next = dget(real);
for (;;) {
parent = dget_parent(next);
if (parent == real_connected)
break;
/*
* If real has been moved out of 'real_connected',
* we will not find 'real_connected' and hit the layer
* root. In that case, we need to restart connecting.
* This game can go on forever in the worst case. We
* may want to consider taking s_vfs_rename_mutex if
* this happens more than once.
*/
if (parent == layer->mnt->mnt_root) {
dput(connected);
connected = dget(sb->s_root);
break;
}
/*
* If real file has been moved out of the layer root
* directory, we will eventully hit the real fs root.
* This cannot happen by legit overlay rename, so we
* return error in that case.
*/
if (parent == next) {
err = -EXDEV;
break;
}
dput(next);
next = parent;
}
if (!err) {
this = ovl_lookup_real_one(connected, next, layer);
if (IS_ERR(this))
err = PTR_ERR(this);
/*
* Lookup of child in overlay can fail when racing with
* overlay rename of child away from 'connected' parent.
* In this case, we need to restart the lookup from the
* top, because we cannot trust that 'real_connected' is
* still an ancestor of 'real'. There is a good chance
* that the renamed overlay ancestor is now in cache, so
* ovl_lookup_real_ancestor() will find it and we can
* continue to connect exactly from where lookup failed.
*/
if (err == -ECHILD) {
this = ovl_lookup_real_ancestor(sb, real,
layer);
err = PTR_ERR_OR_ZERO(this);
}
if (!err) {
dput(connected);
connected = this;
}
}
dput(parent);
dput(next);
}
if (err)
goto fail;
return connected;
fail:
pr_warn_ratelimited("failed to lookup by real (%pd2, layer=%d, connected=%pd2, err=%i)\n",
real, layer->idx, connected, err);
dput(connected);
return ERR_PTR(err);
}
/*
* Get an overlay dentry from upper/lower real dentries and index.
*/
static struct dentry *ovl_get_dentry(struct super_block *sb,
struct dentry *upper,
struct ovl_path *lowerpath,
struct dentry *index)
{
struct ovl_fs *ofs = OVL_FS(sb);
const struct ovl_layer *layer = upper ? &ofs->layers[0] : lowerpath->layer;
struct dentry *real = upper ?: (index ?: lowerpath->dentry);
/*
* Obtain a disconnected overlay dentry from a non-dir real dentry
* and index.
*/
if (!d_is_dir(real))
return ovl_obtain_alias(sb, upper, lowerpath, index);
/* Removed empty directory? */
if ((real->d_flags & DCACHE_DISCONNECTED) || d_unhashed(real))
return ERR_PTR(-ENOENT);
/*
* If real dentry is connected and hashed, get a connected overlay
* dentry whose real dentry is @real.
*/
return ovl_lookup_real(sb, real, layer);
}
static struct dentry *ovl_upper_fh_to_d(struct super_block *sb,
struct ovl_fh *fh)
{
struct ovl_fs *ofs = OVL_FS(sb);
struct dentry *dentry;
struct dentry *upper;
if (!ovl_upper_mnt(ofs))
return ERR_PTR(-EACCES);
upper = ovl_decode_real_fh(ofs, fh, ovl_upper_mnt(ofs), true);
if (IS_ERR_OR_NULL(upper))
return upper;
dentry = ovl_get_dentry(sb, upper, NULL, NULL);
dput(upper);
return dentry;
}
static struct dentry *ovl_lower_fh_to_d(struct super_block *sb,
struct ovl_fh *fh)
{
struct ovl_fs *ofs = OVL_FS(sb);
struct ovl_path origin = { };
struct ovl_path *stack = &origin;
struct dentry *dentry = NULL;
struct dentry *index = NULL;
struct inode *inode;
int err;
/* First lookup overlay inode in inode cache by origin fh */
err = ovl_check_origin_fh(ofs, fh, false, NULL, &stack);
if (err)
return ERR_PTR(err);
if (!d_is_dir(origin.dentry) ||
!(origin.dentry->d_flags & DCACHE_DISCONNECTED)) {
inode = ovl_lookup_inode(sb, origin.dentry, false);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out_err;
if (inode) {
dentry = d_find_any_alias(inode);
iput(inode);
if (dentry)
goto out;
}
}
/* Then lookup indexed upper/whiteout by origin fh */
if (ovl_indexdir(sb)) {
index = ovl_get_index_fh(ofs, fh);
err = PTR_ERR(index);
if (IS_ERR(index)) {
index = NULL;
goto out_err;
}
}
/* Then try to get a connected upper dir by index */
if (index && d_is_dir(index)) {
struct dentry *upper = ovl_index_upper(ofs, index, true);
err = PTR_ERR(upper);
if (IS_ERR_OR_NULL(upper))
goto out_err;
dentry = ovl_get_dentry(sb, upper, NULL, NULL);
dput(upper);
goto out;
}
/* Find origin.dentry again with ovl_acceptable() layer check */
if (d_is_dir(origin.dentry)) {
dput(origin.dentry);
origin.dentry = NULL;
err = ovl_check_origin_fh(ofs, fh, true, NULL, &stack);
if (err)
goto out_err;
}
if (index) {
err = ovl_verify_origin(ofs, index, origin.dentry, false);
if (err)
goto out_err;
}
/* Get a connected non-upper dir or disconnected non-dir */
dentry = ovl_get_dentry(sb, NULL, &origin, index);
out:
dput(origin.dentry);
dput(index);
return dentry;
out_err:
dentry = ERR_PTR(err);
goto out;
}
static struct ovl_fh *ovl_fid_to_fh(struct fid *fid, int buflen, int fh_type)
{
struct ovl_fh *fh;
/* If on-wire inner fid is aligned - nothing to do */
if (fh_type == OVL_FILEID_V1)
return (struct ovl_fh *)fid;
if (fh_type != OVL_FILEID_V0)
return ERR_PTR(-EINVAL);
if (buflen <= OVL_FH_WIRE_OFFSET)
return ERR_PTR(-EINVAL);
fh = kzalloc(buflen, GFP_KERNEL);
if (!fh)
return ERR_PTR(-ENOMEM);
/* Copy unaligned inner fh into aligned buffer */
memcpy(fh->buf, fid, buflen - OVL_FH_WIRE_OFFSET);
return fh;
}
static struct dentry *ovl_fh_to_dentry(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct dentry *dentry = NULL;
struct ovl_fh *fh = NULL;
int len = fh_len << 2;
unsigned int flags = 0;
int err;
fh = ovl_fid_to_fh(fid, len, fh_type);
err = PTR_ERR(fh);
if (IS_ERR(fh))
goto out_err;
err = ovl_check_fh_len(fh, len);
if (err)
goto out_err;
flags = fh->fb.flags;
dentry = (flags & OVL_FH_FLAG_PATH_UPPER) ?
ovl_upper_fh_to_d(sb, fh) :
ovl_lower_fh_to_d(sb, fh);
err = PTR_ERR(dentry);
if (IS_ERR(dentry) && err != -ESTALE)
goto out_err;
out:
/* We may have needed to re-align OVL_FILEID_V0 */
if (!IS_ERR_OR_NULL(fh) && fh != (void *)fid)
kfree(fh);
return dentry;
out_err:
pr_warn_ratelimited("failed to decode file handle (len=%d, type=%d, flags=%x, err=%i)\n",
fh_len, fh_type, flags, err);
dentry = ERR_PTR(err);
goto out;
}
static struct dentry *ovl_fh_to_parent(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
pr_warn_ratelimited("connectable file handles not supported; use 'no_subtree_check' exportfs option.\n");
return ERR_PTR(-EACCES);
}
static int ovl_get_name(struct dentry *parent, char *name,
struct dentry *child)
{
/*
* ovl_fh_to_dentry() returns connected dir overlay dentries and
* ovl_fh_to_parent() is not implemented, so we should not get here.
*/
WARN_ON_ONCE(1);
return -EIO;
}
static struct dentry *ovl_get_parent(struct dentry *dentry)
{
/*
* ovl_fh_to_dentry() returns connected dir overlay dentries, so we
* should not get here.
*/
WARN_ON_ONCE(1);
return ERR_PTR(-EIO);
}
const struct export_operations ovl_export_operations = {
.encode_fh = ovl_encode_fh,
.fh_to_dentry = ovl_fh_to_dentry,
.fh_to_parent = ovl_fh_to_parent,
.get_name = ovl_get_name,
.get_parent = ovl_get_parent,
};
/* encode_fh() encodes non-decodable file handles with nfs_export=off */
const struct export_operations ovl_export_fid_operations = {
.encode_fh = ovl_encode_fh,
};
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