[people/ms/linux.git] / fs / overlayfs / inode.c

/*
 *
 * Copyright (C) 2011 Novell Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/xattr.h>
#include "overlayfs.h"

static int ovl_copy_up_truncate(struct dentry *dentry)
{
	int err;
	struct dentry *parent;
	struct kstat stat;
	struct path lowerpath;

	parent = dget_parent(dentry);
	err = ovl_copy_up(parent);
	if (err)
		goto out_dput_parent;

	ovl_path_lower(dentry, &lowerpath);
	err = vfs_getattr(&lowerpath, &stat);
	if (err)
		goto out_dput_parent;

	stat.size = 0;
	err = ovl_copy_up_one(parent, dentry, &lowerpath, &stat);

out_dput_parent:
	dput(parent);
	return err;
}

int ovl_setattr(struct dentry *dentry, struct iattr *attr)
{
	int err;
	struct dentry *upperdentry;

	err = ovl_want_write(dentry);
	if (err)
		goto out;

	err = ovl_copy_up(dentry);
	if (!err) {
		upperdentry = ovl_dentry_upper(dentry);

		mutex_lock(&upperdentry->d_inode->i_mutex);
		err = notify_change(upperdentry, attr, NULL);
		mutex_unlock(&upperdentry->d_inode->i_mutex);
	}
	ovl_drop_write(dentry);
out:
	return err;
}

static int ovl_getattr(struct vfsmount *mnt, struct dentry *dentry,
			 struct kstat *stat)
{
	struct path realpath;

	ovl_path_real(dentry, &realpath);
	return vfs_getattr(&realpath, stat);
}

int ovl_permission(struct inode *inode, int mask)
{
	struct ovl_entry *oe;
	struct dentry *alias = NULL;
	struct inode *realinode;
	struct dentry *realdentry;
	bool is_upper;
	int err;

	if (S_ISDIR(inode->i_mode)) {
		oe = inode->i_private;
	} else if (mask & MAY_NOT_BLOCK) {
		return -ECHILD;
	} else {
		/*
		 * For non-directories find an alias and get the info
		 * from there.
		 */
		alias = d_find_any_alias(inode);
		if (WARN_ON(!alias))
			return -ENOENT;

		oe = alias->d_fsdata;
	}

	realdentry = ovl_entry_real(oe, &is_upper);

	/* Careful in RCU walk mode */
	realinode = ACCESS_ONCE(realdentry->d_inode);
	if (!realinode) {
		WARN_ON(!(mask & MAY_NOT_BLOCK));
		err = -ENOENT;
		goto out_dput;
	}

	if (mask & MAY_WRITE) {
		umode_t mode = realinode->i_mode;

		/*
		 * Writes will always be redirected to upper layer, so
		 * ignore lower layer being read-only.
		 *
		 * If the overlay itself is read-only then proceed
		 * with the permission check, don't return EROFS.
		 * This will only happen if this is the lower layer of
		 * another overlayfs.
		 *
		 * If upper fs becomes read-only after the overlay was
		 * constructed return EROFS to prevent modification of
		 * upper layer.
		 */
		err = -EROFS;
		if (is_upper && !IS_RDONLY(inode) && IS_RDONLY(realinode) &&
		    (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
			goto out_dput;
	}

	err = __inode_permission(realinode, mask);
out_dput:
	dput(alias);
	return err;
}


struct ovl_link_data {
	struct dentry *realdentry;
	void *cookie;
};

static const char *ovl_follow_link(struct dentry *dentry, void **cookie)
{
	struct dentry *realdentry;
	struct inode *realinode;
	struct ovl_link_data *data = NULL;
	const char *ret;

	realdentry = ovl_dentry_real(dentry);
	realinode = realdentry->d_inode;

	if (WARN_ON(!realinode->i_op->follow_link))
		return ERR_PTR(-EPERM);

	if (realinode->i_op->put_link) {
		data = kmalloc(sizeof(struct ovl_link_data), GFP_KERNEL);
		if (!data)
			return ERR_PTR(-ENOMEM);
		data->realdentry = realdentry;
	}

	ret = realinode->i_op->follow_link(realdentry, cookie);
	if (IS_ERR_OR_NULL(ret)) {
		kfree(data);
		return ret;
	}

	if (data)
		data->cookie = *cookie;

	*cookie = data;

	return ret;
}

static void ovl_put_link(struct inode *unused, void *c)
{
	struct inode *realinode;
	struct ovl_link_data *data = c;

	if (!data)
		return;

	realinode = data->realdentry->d_inode;
	realinode->i_op->put_link(realinode, data->cookie);
	kfree(data);
}

static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
{
	struct path realpath;
	struct inode *realinode;

	ovl_path_real(dentry, &realpath);
	realinode = realpath.dentry->d_inode;

	if (!realinode->i_op->readlink)
		return -EINVAL;

	touch_atime(&realpath);

	return realinode->i_op->readlink(realpath.dentry, buf, bufsiz);
}


static bool ovl_is_private_xattr(const char *name)
{
	return strncmp(name, OVL_XATTR_PRE_NAME, OVL_XATTR_PRE_LEN) == 0;
}

int ovl_setxattr(struct dentry *dentry, const char *name,
		 const void *value, size_t size, int flags)
{
	int err;
	struct dentry *upperdentry;

	err = ovl_want_write(dentry);
	if (err)
		goto out;

	err = -EPERM;
	if (ovl_is_private_xattr(name))
		goto out_drop_write;

	err = ovl_copy_up(dentry);
	if (err)
		goto out_drop_write;

	upperdentry = ovl_dentry_upper(dentry);
	err = vfs_setxattr(upperdentry, name, value, size, flags);

out_drop_write:
	ovl_drop_write(dentry);
out:
	return err;
}

static bool ovl_need_xattr_filter(struct dentry *dentry,
				  enum ovl_path_type type)
{
	if ((type & (__OVL_PATH_PURE | __OVL_PATH_UPPER)) == __OVL_PATH_UPPER)
		return S_ISDIR(dentry->d_inode->i_mode);
	else
		return false;
}

ssize_t ovl_getxattr(struct dentry *dentry, const char *name,
		     void *value, size_t size)
{
	struct path realpath;
	enum ovl_path_type type = ovl_path_real(dentry, &realpath);

	if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
		return -ENODATA;

	return vfs_getxattr(realpath.dentry, name, value, size);
}

ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
{
	struct path realpath;
	enum ovl_path_type type = ovl_path_real(dentry, &realpath);
	ssize_t res;
	int off;

	res = vfs_listxattr(realpath.dentry, list, size);
	if (res <= 0 || size == 0)
		return res;

	if (!ovl_need_xattr_filter(dentry, type))
		return res;

	/* filter out private xattrs */
	for (off = 0; off < res;) {
		char *s = list + off;
		size_t slen = strlen(s) + 1;

		BUG_ON(off + slen > res);

		if (ovl_is_private_xattr(s)) {
			res -= slen;
			memmove(s, s + slen, res - off);
		} else {
			off += slen;
		}
	}

	return res;
}

int ovl_removexattr(struct dentry *dentry, const char *name)
{
	int err;
	struct path realpath;
	enum ovl_path_type type = ovl_path_real(dentry, &realpath);

	err = ovl_want_write(dentry);
	if (err)
		goto out;

	err = -ENODATA;
	if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
		goto out_drop_write;

	if (!OVL_TYPE_UPPER(type)) {
		err = vfs_getxattr(realpath.dentry, name, NULL, 0);
		if (err < 0)
			goto out_drop_write;

		err = ovl_copy_up(dentry);
		if (err)
			goto out_drop_write;

		ovl_path_upper(dentry, &realpath);
	}

	err = vfs_removexattr(realpath.dentry, name);
out_drop_write:
	ovl_drop_write(dentry);
out:
	return err;
}

static bool ovl_open_need_copy_up(int flags, enum ovl_path_type type,
				  struct dentry *realdentry)
{
	if (OVL_TYPE_UPPER(type))
		return false;

	if (special_file(realdentry->d_inode->i_mode))
		return false;

	if (!(OPEN_FMODE(flags) & FMODE_WRITE) && !(flags & O_TRUNC))
		return false;

	return true;
}

struct inode *ovl_d_select_inode(struct dentry *dentry, unsigned file_flags)
{
	int err;
	struct path realpath;
	enum ovl_path_type type;

	if (d_is_dir(dentry))
		return d_backing_inode(dentry);

	type = ovl_path_real(dentry, &realpath);
	if (ovl_open_need_copy_up(file_flags, type, realpath.dentry)) {
		err = ovl_want_write(dentry);
		if (err)
			return ERR_PTR(err);

		if (file_flags & O_TRUNC)
			err = ovl_copy_up_truncate(dentry);
		else
			err = ovl_copy_up(dentry);
		ovl_drop_write(dentry);
		if (err)
			return ERR_PTR(err);

		ovl_path_upper(dentry, &realpath);
	}

	if (realpath.dentry->d_flags & DCACHE_OP_SELECT_INODE)
		return realpath.dentry->d_op->d_select_inode(realpath.dentry, file_flags);

	return d_backing_inode(realpath.dentry);
}

static const struct inode_operations ovl_file_inode_operations = {
	.setattr	= ovl_setattr,
	.permission	= ovl_permission,
	.getattr	= ovl_getattr,
	.setxattr	= ovl_setxattr,
	.getxattr	= ovl_getxattr,
	.listxattr	= ovl_listxattr,
	.removexattr	= ovl_removexattr,
};

static const struct inode_operations ovl_symlink_inode_operations = {
	.setattr	= ovl_setattr,
	.follow_link	= ovl_follow_link,
	.put_link	= ovl_put_link,
	.readlink	= ovl_readlink,
	.getattr	= ovl_getattr,
	.setxattr	= ovl_setxattr,
	.getxattr	= ovl_getxattr,
	.listxattr	= ovl_listxattr,
	.removexattr	= ovl_removexattr,
};

struct inode *ovl_new_inode(struct super_block *sb, umode_t mode,
			    struct ovl_entry *oe)
{
	struct inode *inode;

	inode = new_inode(sb);
	if (!inode)
		return NULL;

	mode &= S_IFMT;

	inode->i_ino = get_next_ino();
	inode->i_mode = mode;
	inode->i_flags |= S_NOATIME | S_NOCMTIME;

	switch (mode) {
	case S_IFDIR:
		inode->i_private = oe;
		inode->i_op = &ovl_dir_inode_operations;
		inode->i_fop = &ovl_dir_operations;
		break;

	case S_IFLNK:
		inode->i_op = &ovl_symlink_inode_operations;
		break;

	case S_IFREG:
	case S_IFSOCK:
	case S_IFBLK:
	case S_IFCHR:
	case S_IFIFO:
		inode->i_op = &ovl_file_inode_operations;
		break;

	default:
		WARN(1, "illegal file type: %i\n", mode);
		iput(inode);
		inode = NULL;
	}

	return inode;
}
Commit	Line	Data
e9be9d5e MS	1	/*
	2	*
	3	* Copyright (C) 2011 Novell Inc.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License version 2 as published by
	7	* the Free Software Foundation.
	8	*/
	9
	10	#include <linux/fs.h>
	11	#include <linux/slab.h>
	12	#include <linux/xattr.h>
	13	#include "overlayfs.h"
	14
0f7ff2da	15	static int ovl_copy_up_truncate(struct dentry *dentry)
e9be9d5e MS	16	{
	17	int err;
	18	struct dentry *parent;
	19	struct kstat stat;
	20	struct path lowerpath;
	21
	22	parent = dget_parent(dentry);
	23	err = ovl_copy_up(parent);
	24	if (err)
	25	goto out_dput_parent;
	26
	27	ovl_path_lower(dentry, &lowerpath);
	28	err = vfs_getattr(&lowerpath, &stat);
	29	if (err)
	30	goto out_dput_parent;
	31
0f7ff2da AV	32	stat.size = 0;
0f7ff2da AV	33	err = ovl_copy_up_one(parent, dentry, &lowerpath, &stat);
e9be9d5e MS	34
	35	out_dput_parent:
	36	dput(parent);
	37	return err;
	38	}
	39
	40	int ovl_setattr(struct dentry dentry, struct iattr attr)
	41	{
	42	int err;
	43	struct dentry *upperdentry;
	44
	45	err = ovl_want_write(dentry);
	46	if (err)
	47	goto out;
	48
acff81ec MS	49	err = ovl_copy_up(dentry);
	50	if (!err) {
	51	upperdentry = ovl_dentry_upper(dentry);
	52
e9be9d5e MS	53	mutex_lock(&upperdentry->d_inode->i_mutex);
	54	err = notify_change(upperdentry, attr, NULL);
	55	mutex_unlock(&upperdentry->d_inode->i_mutex);
e9be9d5e MS	56	}
	57	ovl_drop_write(dentry);
	58	out:
	59	return err;
	60	}
	61
	62	static int ovl_getattr(struct vfsmount mnt, struct dentry dentry,
	63	struct kstat *stat)
	64	{
	65	struct path realpath;
	66
	67	ovl_path_real(dentry, &realpath);
	68	return vfs_getattr(&realpath, stat);
	69	}
	70
	71	int ovl_permission(struct inode *inode, int mask)
	72	{
	73	struct ovl_entry *oe;
	74	struct dentry *alias = NULL;
	75	struct inode *realinode;
	76	struct dentry *realdentry;
	77	bool is_upper;
	78	int err;
	79
	80	if (S_ISDIR(inode->i_mode)) {
	81	oe = inode->i_private;
	82	} else if (mask & MAY_NOT_BLOCK) {
	83	return -ECHILD;
	84	} else {
	85	/*
	86	* For non-directories find an alias and get the info
	87	* from there.
	88	*/
	89	alias = d_find_any_alias(inode);
	90	if (WARN_ON(!alias))
	91	return -ENOENT;
	92
	93	oe = alias->d_fsdata;
	94	}
	95
	96	realdentry = ovl_entry_real(oe, &is_upper);
	97
	98	/* Careful in RCU walk mode */
	99	realinode = ACCESS_ONCE(realdentry->d_inode);
	100	if (!realinode) {
	101	WARN_ON(!(mask & MAY_NOT_BLOCK));
	102	err = -ENOENT;
	103	goto out_dput;
	104	}
	105
	106	if (mask & MAY_WRITE) {
	107	umode_t mode = realinode->i_mode;
	108
	109	/*
	110	* Writes will always be redirected to upper layer, so
	111	* ignore lower layer being read-only.
	112	*
	113	* If the overlay itself is read-only then proceed
	114	* with the permission check, don't return EROFS.
	115	* This will only happen if this is the lower layer of
	116	* another overlayfs.
	117	*
	118	* If upper fs becomes read-only after the overlay was
	119	* constructed return EROFS to prevent modification of
120	* upper layer.
121	*/
122	err = -EROFS;
123	if (is_upper && !IS_RDONLY(inode) && IS_RDONLY(realinode) &&
124	(S_ISREG(mode) \|\| S_ISDIR(mode) \|\| S_ISLNK(mode)))
125	goto out_dput;
126	}
127
128	err = __inode_permission(realinode, mask);
129	out_dput:
130	dput(alias);
131	return err;
132	}
133
134
135	struct ovl_link_data {
136	struct dentry *realdentry;
137	void *cookie;
138	};
139
6e77137b	140	static const char ovl_follow_link(struct dentry dentry, void **cookie)
e9be9d5e	141	{
e9be9d5e MS	142	struct dentry *realdentry;
e9be9d5e MS	143	struct inode *realinode;
3188b295	144	struct ovl_link_data *data = NULL;
680baacb	145	const char *ret;
e9be9d5e MS	146
	147	realdentry = ovl_dentry_real(dentry);
	148	realinode = realdentry->d_inode;
	149
	150	if (WARN_ON(!realinode->i_op->follow_link))
	151	return ERR_PTR(-EPERM);
	152
e9be9d5e	153	if (realinode->i_op->put_link) {
e9be9d5e	154	data = kmalloc(sizeof(struct ovl_link_data), GFP_KERNEL);
3188b295	155	if (!data)
e9be9d5e	156	return ERR_PTR(-ENOMEM);
e9be9d5e	157	data->realdentry = realdentry;
3188b295	158	}
e9be9d5e	159
6e77137b	160	ret = realinode->i_op->follow_link(realdentry, cookie);
680baacb	161	if (IS_ERR_OR_NULL(ret)) {
3188b295 N	162	kfree(data);
3188b295 N	163	return ret;
e9be9d5e	164	}
3188b295 N	165
3188b295 N	166	if (data)
680baacb	167	data->cookie = *cookie;
3188b295	168
680baacb AV	169	*cookie = data;
	170
	171	return ret;
e9be9d5e MS	172	}
e9be9d5e MS	173
5f2c4179	174	static void ovl_put_link(struct inode unused, void c)
e9be9d5e MS	175	{
	176	struct inode *realinode;
	177	struct ovl_link_data *data = c;
	178
	179	if (!data)
	180	return;
	181
	182	realinode = data->realdentry->d_inode;
5f2c4179	183	realinode->i_op->put_link(realinode, data->cookie);
e9be9d5e MS	184	kfree(data);
	185	}
	186
	187	static int ovl_readlink(struct dentry dentry, char __user buf, int bufsiz)
	188	{
	189	struct path realpath;
	190	struct inode *realinode;
	191
	192	ovl_path_real(dentry, &realpath);
	193	realinode = realpath.dentry->d_inode;
	194
	195	if (!realinode->i_op->readlink)
	196	return -EINVAL;
	197
	198	touch_atime(&realpath);
	199
	200	return realinode->i_op->readlink(realpath.dentry, buf, bufsiz);
	201	}
	202
	203
	204	static bool ovl_is_private_xattr(const char *name)
	205	{
cead89bb	206	return strncmp(name, OVL_XATTR_PRE_NAME, OVL_XATTR_PRE_LEN) == 0;
e9be9d5e MS	207	}
	208
	209	int ovl_setxattr(struct dentry dentry, const char name,
	210	const void *value, size_t size, int flags)
	211	{
	212	int err;
	213	struct dentry *upperdentry;
	214
	215	err = ovl_want_write(dentry);
	216	if (err)
	217	goto out;
	218
	219	err = -EPERM;
	220	if (ovl_is_private_xattr(name))
	221	goto out_drop_write;
	222
	223	err = ovl_copy_up(dentry);
	224	if (err)
	225	goto out_drop_write;
	226
	227	upperdentry = ovl_dentry_upper(dentry);
	228	err = vfs_setxattr(upperdentry, name, value, size, flags);
	229
	230	out_drop_write:
	231	ovl_drop_write(dentry);
	232	out:
	233	return err;
	234	}
	235
52148463 MS	236	static bool ovl_need_xattr_filter(struct dentry *dentry,
	237	enum ovl_path_type type)
	238	{
1afaba1e MS	239	if ((type & (__OVL_PATH_PURE \| __OVL_PATH_UPPER)) == __OVL_PATH_UPPER)
	240	return S_ISDIR(dentry->d_inode->i_mode);
	241	else
	242	return false;
52148463 MS	243	}
52148463 MS	244
e9be9d5e MS	245	ssize_t ovl_getxattr(struct dentry dentry, const char name,
	246	void *value, size_t size)
	247	{
52148463 MS	248	struct path realpath;
	249	enum ovl_path_type type = ovl_path_real(dentry, &realpath);
	250
	251	if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
e9be9d5e MS	252	return -ENODATA;
e9be9d5e MS	253
52148463	254	return vfs_getxattr(realpath.dentry, name, value, size);
e9be9d5e MS	255	}
	256
	257	ssize_t ovl_listxattr(struct dentry dentry, char list, size_t size)
	258	{
52148463 MS	259	struct path realpath;
52148463 MS	260	enum ovl_path_type type = ovl_path_real(dentry, &realpath);
e9be9d5e MS	261	ssize_t res;
	262	int off;
	263
52148463	264	res = vfs_listxattr(realpath.dentry, list, size);
e9be9d5e MS	265	if (res <= 0 \|\| size == 0)
	266	return res;
	267
52148463	268	if (!ovl_need_xattr_filter(dentry, type))
e9be9d5e MS	269	return res;
	270
	271	/* filter out private xattrs */
	272	for (off = 0; off < res;) {
	273	char *s = list + off;
	274	size_t slen = strlen(s) + 1;
	275
	276	BUG_ON(off + slen > res);
	277
	278	if (ovl_is_private_xattr(s)) {
	279	res -= slen;
	280	memmove(s, s + slen, res - off);
	281	} else {
	282	off += slen;
	283	}
	284	}
	285
	286	return res;
	287	}
	288
	289	int ovl_removexattr(struct dentry dentry, const char name)
	290	{
	291	int err;
	292	struct path realpath;
52148463	293	enum ovl_path_type type = ovl_path_real(dentry, &realpath);
e9be9d5e MS	294
	295	err = ovl_want_write(dentry);
	296	if (err)
	297	goto out;
	298
52148463 MS	299	err = -ENODATA;
52148463 MS	300	if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name))
e9be9d5e MS	301	goto out_drop_write;
e9be9d5e MS	302
1afaba1e	303	if (!OVL_TYPE_UPPER(type)) {
e9be9d5e MS	304	err = vfs_getxattr(realpath.dentry, name, NULL, 0);
	305	if (err < 0)
	306	goto out_drop_write;
	307
	308	err = ovl_copy_up(dentry);
	309	if (err)
	310	goto out_drop_write;
	311
	312	ovl_path_upper(dentry, &realpath);
	313	}
	314
	315	err = vfs_removexattr(realpath.dentry, name);
	316	out_drop_write:
	317	ovl_drop_write(dentry);
	318	out:
	319	return err;
	320	}
	321
	322	static bool ovl_open_need_copy_up(int flags, enum ovl_path_type type,
	323	struct dentry *realdentry)
	324	{
1afaba1e	325	if (OVL_TYPE_UPPER(type))
e9be9d5e MS	326	return false;
	327
	328	if (special_file(realdentry->d_inode->i_mode))
	329	return false;
	330
	331	if (!(OPEN_FMODE(flags) & FMODE_WRITE) && !(flags & O_TRUNC))
	332	return false;
	333
	334	return true;
	335	}
	336
4bacc9c9	337	struct inode ovl_d_select_inode(struct dentry dentry, unsigned file_flags)
e9be9d5e MS	338	{
	339	int err;
	340	struct path realpath;
	341	enum ovl_path_type type;
e9be9d5e	342
9391dd00 AV	343	if (d_is_dir(dentry))
	344	return d_backing_inode(dentry);
	345
e9be9d5e	346	type = ovl_path_real(dentry, &realpath);
4bacc9c9	347	if (ovl_open_need_copy_up(file_flags, type, realpath.dentry)) {
e9be9d5e MS	348	err = ovl_want_write(dentry);
e9be9d5e MS	349	if (err)
4bacc9c9	350	return ERR_PTR(err);
e9be9d5e	351
4bacc9c9	352	if (file_flags & O_TRUNC)
0f7ff2da	353	err = ovl_copy_up_truncate(dentry);
e9be9d5e MS	354	else
e9be9d5e MS	355	err = ovl_copy_up(dentry);
f25801ee	356	ovl_drop_write(dentry);
e9be9d5e	357	if (err)
4bacc9c9	358	return ERR_PTR(err);
e9be9d5e MS	359
	360	ovl_path_upper(dentry, &realpath);
	361	}
	362
1c8a47df MS	363	if (realpath.dentry->d_flags & DCACHE_OP_SELECT_INODE)
	364	return realpath.dentry->d_op->d_select_inode(realpath.dentry, file_flags);
	365
4bacc9c9	366	return d_backing_inode(realpath.dentry);
e9be9d5e MS	367	}
	368
	369	static const struct inode_operations ovl_file_inode_operations = {
	370	.setattr = ovl_setattr,
	371	.permission = ovl_permission,
	372	.getattr = ovl_getattr,
	373	.setxattr = ovl_setxattr,
	374	.getxattr = ovl_getxattr,
	375	.listxattr = ovl_listxattr,
	376	.removexattr = ovl_removexattr,
e9be9d5e MS	377	};
	378
	379	static const struct inode_operations ovl_symlink_inode_operations = {
	380	.setattr = ovl_setattr,
	381	.follow_link = ovl_follow_link,
	382	.put_link = ovl_put_link,
	383	.readlink = ovl_readlink,
	384	.getattr = ovl_getattr,
	385	.setxattr = ovl_setxattr,
	386	.getxattr = ovl_getxattr,
	387	.listxattr = ovl_listxattr,
	388	.removexattr = ovl_removexattr,
	389	};
	390
	391	struct inode ovl_new_inode(struct super_block sb, umode_t mode,
	392	struct ovl_entry *oe)
	393	{
	394	struct inode *inode;
	395
	396	inode = new_inode(sb);
	397	if (!inode)
	398	return NULL;
	399
	400	mode &= S_IFMT;
	401
	402	inode->i_ino = get_next_ino();
	403	inode->i_mode = mode;
	404	inode->i_flags \|= S_NOATIME \| S_NOCMTIME;
	405
	406	switch (mode) {
	407	case S_IFDIR:
	408	inode->i_private = oe;
	409	inode->i_op = &ovl_dir_inode_operations;
	410	inode->i_fop = &ovl_dir_operations;
	411	break;
	412
	413	case S_IFLNK:
	414	inode->i_op = &ovl_symlink_inode_operations;
	415	break;
	416
	417	case S_IFREG:
	418	case S_IFSOCK:
	419	case S_IFBLK:
	420	case S_IFCHR:
	421	case S_IFIFO:
	422	inode->i_op = &ovl_file_inode_operations;
	423	break;
	424
	425	default:
	426	WARN(1, "illegal file type: %i\n", mode);
	427	iput(inode);
	428	inode = NULL;
	429	}
	430
	431	return inode;
e9be9d5e	432	}