overlayfs.h revision 096a218a
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 *
4 * Copyright (C) 2011 Novell Inc.
5 */
6
7#include <linux/kernel.h>
8#include <linux/uuid.h>
9#include <linux/fs.h>
10#include "ovl_entry.h"
11
12#undef pr_fmt
13#define pr_fmt(fmt) "overlayfs: " fmt
14
15enum ovl_path_type {
16	__OVL_PATH_UPPER	= (1 << 0),
17	__OVL_PATH_MERGE	= (1 << 1),
18	__OVL_PATH_ORIGIN	= (1 << 2),
19};
20
21#define OVL_TYPE_UPPER(type)	((type) & __OVL_PATH_UPPER)
22#define OVL_TYPE_MERGE(type)	((type) & __OVL_PATH_MERGE)
23#define OVL_TYPE_ORIGIN(type)	((type) & __OVL_PATH_ORIGIN)
24
25#define OVL_XATTR_NAMESPACE "overlay."
26#define OVL_XATTR_TRUSTED_PREFIX XATTR_TRUSTED_PREFIX OVL_XATTR_NAMESPACE
27#define OVL_XATTR_USER_PREFIX XATTR_USER_PREFIX OVL_XATTR_NAMESPACE
28
29enum ovl_xattr {
30	OVL_XATTR_OPAQUE,
31	OVL_XATTR_REDIRECT,
32	OVL_XATTR_ORIGIN,
33	OVL_XATTR_IMPURE,
34	OVL_XATTR_NLINK,
35	OVL_XATTR_UPPER,
36	OVL_XATTR_METACOPY,
37	OVL_XATTR_PROTATTR,
38};
39
40enum ovl_inode_flag {
41	/* Pure upper dir that may contain non pure upper entries */
42	OVL_IMPURE,
43	/* Non-merge dir that may contain whiteout entries */
44	OVL_WHITEOUTS,
45	OVL_INDEX,
46	OVL_UPPERDATA,
47	/* Inode number will remain constant over copy up. */
48	OVL_CONST_INO,
49};
50
51enum ovl_entry_flag {
52	OVL_E_UPPER_ALIAS,
53	OVL_E_OPAQUE,
54	OVL_E_CONNECTED,
55};
56
57enum {
58	OVL_XINO_OFF,
59	OVL_XINO_AUTO,
60	OVL_XINO_ON,
61};
62
63/*
64 * The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
65 * where:
66 * origin.fh	- exported file handle of the lower file
67 * origin.uuid	- uuid of the lower filesystem
68 */
69#define OVL_FH_VERSION	0
70#define OVL_FH_MAGIC	0xfb
71
72/* CPU byte order required for fid decoding:  */
73#define OVL_FH_FLAG_BIG_ENDIAN	(1 << 0)
74#define OVL_FH_FLAG_ANY_ENDIAN	(1 << 1)
75/* Is the real inode encoded in fid an upper inode? */
76#define OVL_FH_FLAG_PATH_UPPER	(1 << 2)
77
78#define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN | \
79			 OVL_FH_FLAG_PATH_UPPER)
80
81#if defined(__LITTLE_ENDIAN)
82#define OVL_FH_FLAG_CPU_ENDIAN 0
83#elif defined(__BIG_ENDIAN)
84#define OVL_FH_FLAG_CPU_ENDIAN OVL_FH_FLAG_BIG_ENDIAN
85#else
86#error Endianness not defined
87#endif
88
89/* The type used to be returned by overlay exportfs for misaligned fid */
90#define OVL_FILEID_V0	0xfb
91/* The type returned by overlay exportfs for 32bit aligned fid */
92#define OVL_FILEID_V1	0xf8
93
94/* On-disk format for "origin" file handle */
95struct ovl_fb {
96	u8 version;	/* 0 */
97	u8 magic;	/* 0xfb */
98	u8 len;		/* size of this header + size of fid */
99	u8 flags;	/* OVL_FH_FLAG_* */
100	u8 type;	/* fid_type of fid */
101	uuid_t uuid;	/* uuid of filesystem */
102	u32 fid[];	/* file identifier should be 32bit aligned in-memory */
103} __packed;
104
105/* In-memory and on-wire format for overlay file handle */
106struct ovl_fh {
107	u8 padding[3];	/* make sure fb.fid is 32bit aligned */
108	union {
109		struct ovl_fb fb;
110		u8 buf[0];
111	};
112} __packed;
113
114#define OVL_FH_WIRE_OFFSET	offsetof(struct ovl_fh, fb)
115#define OVL_FH_LEN(fh)		(OVL_FH_WIRE_OFFSET + (fh)->fb.len)
116#define OVL_FH_FID_OFFSET	(OVL_FH_WIRE_OFFSET + \
117				 offsetof(struct ovl_fb, fid))
118
119extern const char *const ovl_xattr_table[][2];
120static inline const char *ovl_xattr(struct ovl_fs *ofs, enum ovl_xattr ox)
121{
122	return ovl_xattr_table[ox][ofs->config.userxattr];
123}
124
125static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
126{
127	int err = vfs_rmdir(&init_user_ns, dir, dentry);
128
129	pr_debug("rmdir(%pd2) = %i\n", dentry, err);
130	return err;
131}
132
133static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
134{
135	int err = vfs_unlink(&init_user_ns, dir, dentry, NULL);
136
137	pr_debug("unlink(%pd2) = %i\n", dentry, err);
138	return err;
139}
140
141static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
142			      struct dentry *new_dentry)
143{
144	int err = vfs_link(old_dentry, &init_user_ns, dir, new_dentry, NULL);
145
146	pr_debug("link(%pd2, %pd2) = %i\n", old_dentry, new_dentry, err);
147	return err;
148}
149
150static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
151				umode_t mode)
152{
153	int err = vfs_create(&init_user_ns, dir, dentry, mode, true);
154
155	pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
156	return err;
157}
158
159static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
160			       umode_t mode)
161{
162	int err = vfs_mkdir(&init_user_ns, dir, dentry, mode);
163	pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
164	return err;
165}
166
167static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
168			       umode_t mode, dev_t dev)
169{
170	int err = vfs_mknod(&init_user_ns, dir, dentry, mode, dev);
171
172	pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry, mode, dev, err);
173	return err;
174}
175
176static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry,
177				 const char *oldname)
178{
179	int err = vfs_symlink(&init_user_ns, dir, dentry, oldname);
180
181	pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
182	return err;
183}
184
185static inline ssize_t ovl_do_getxattr(struct ovl_fs *ofs, struct dentry *dentry,
186				      enum ovl_xattr ox, void *value,
187				      size_t size)
188{
189	const char *name = ovl_xattr(ofs, ox);
190	int err = vfs_getxattr(&init_user_ns, dentry, name, value, size);
191	int len = (value && err > 0) ? err : 0;
192
193	pr_debug("getxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
194		 dentry, name, min(len, 48), value, size, err);
195	return err;
196}
197
198static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
199				  enum ovl_xattr ox, const void *value,
200				  size_t size)
201{
202	const char *name = ovl_xattr(ofs, ox);
203	int err = vfs_setxattr(&init_user_ns, dentry, name, value, size, 0);
204	pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
205		 dentry, name, min((int)size, 48), value, size, err);
206	return err;
207}
208
209static inline int ovl_do_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
210				     enum ovl_xattr ox)
211{
212	const char *name = ovl_xattr(ofs, ox);
213	int err = vfs_removexattr(&init_user_ns, dentry, name);
214	pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
215	return err;
216}
217
218static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
219				struct inode *newdir, struct dentry *newdentry,
220				unsigned int flags)
221{
222	int err;
223	struct renamedata rd = {
224		.old_mnt_userns	= &init_user_ns,
225		.old_dir 	= olddir,
226		.old_dentry 	= olddentry,
227		.new_mnt_userns	= &init_user_ns,
228		.new_dir 	= newdir,
229		.new_dentry 	= newdentry,
230		.flags 		= flags,
231	};
232
233	pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry, newdentry, flags);
234	err = vfs_rename(&rd);
235	if (err) {
236		pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
237			 olddentry, newdentry, err);
238	}
239	return err;
240}
241
242static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry)
243{
244	int err = vfs_whiteout(&init_user_ns, dir, dentry);
245	pr_debug("whiteout(%pd2) = %i\n", dentry, err);
246	return err;
247}
248
249static inline struct dentry *ovl_do_tmpfile(struct dentry *dentry, umode_t mode)
250{
251	struct dentry *ret = vfs_tmpfile(&init_user_ns, dentry, mode, 0);
252	int err = PTR_ERR_OR_ZERO(ret);
253
254	pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err);
255	return ret;
256}
257
258static inline bool ovl_open_flags_need_copy_up(int flags)
259{
260	if (!flags)
261		return false;
262
263	return ((OPEN_FMODE(flags) & FMODE_WRITE) || (flags & O_TRUNC));
264}
265
266/* util.c */
267int ovl_want_write(struct dentry *dentry);
268void ovl_drop_write(struct dentry *dentry);
269struct dentry *ovl_workdir(struct dentry *dentry);
270const struct cred *ovl_override_creds(struct super_block *sb);
271int ovl_can_decode_fh(struct super_block *sb);
272struct dentry *ovl_indexdir(struct super_block *sb);
273bool ovl_index_all(struct super_block *sb);
274bool ovl_verify_lower(struct super_block *sb);
275struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
276bool ovl_dentry_remote(struct dentry *dentry);
277void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *upperdentry,
278			     unsigned int mask);
279bool ovl_dentry_weird(struct dentry *dentry);
280enum ovl_path_type ovl_path_type(struct dentry *dentry);
281void ovl_path_upper(struct dentry *dentry, struct path *path);
282void ovl_path_lower(struct dentry *dentry, struct path *path);
283void ovl_path_lowerdata(struct dentry *dentry, struct path *path);
284enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
285struct dentry *ovl_dentry_upper(struct dentry *dentry);
286struct dentry *ovl_dentry_lower(struct dentry *dentry);
287struct dentry *ovl_dentry_lowerdata(struct dentry *dentry);
288const struct ovl_layer *ovl_layer_lower(struct dentry *dentry);
289struct dentry *ovl_dentry_real(struct dentry *dentry);
290struct dentry *ovl_i_dentry_upper(struct inode *inode);
291struct inode *ovl_inode_upper(struct inode *inode);
292struct inode *ovl_inode_lower(struct inode *inode);
293struct inode *ovl_inode_lowerdata(struct inode *inode);
294struct inode *ovl_inode_real(struct inode *inode);
295struct inode *ovl_inode_realdata(struct inode *inode);
296struct ovl_dir_cache *ovl_dir_cache(struct inode *inode);
297void ovl_set_dir_cache(struct inode *inode, struct ovl_dir_cache *cache);
298void ovl_dentry_set_flag(unsigned long flag, struct dentry *dentry);
299void ovl_dentry_clear_flag(unsigned long flag, struct dentry *dentry);
300bool ovl_dentry_test_flag(unsigned long flag, struct dentry *dentry);
301bool ovl_dentry_is_opaque(struct dentry *dentry);
302bool ovl_dentry_is_whiteout(struct dentry *dentry);
303void ovl_dentry_set_opaque(struct dentry *dentry);
304bool ovl_dentry_has_upper_alias(struct dentry *dentry);
305void ovl_dentry_set_upper_alias(struct dentry *dentry);
306bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags);
307bool ovl_dentry_needs_data_copy_up_locked(struct dentry *dentry, int flags);
308bool ovl_has_upperdata(struct inode *inode);
309void ovl_set_upperdata(struct inode *inode);
310bool ovl_redirect_dir(struct super_block *sb);
311const char *ovl_dentry_get_redirect(struct dentry *dentry);
312void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect);
313void ovl_inode_update(struct inode *inode, struct dentry *upperdentry);
314void ovl_dir_modified(struct dentry *dentry, bool impurity);
315u64 ovl_dentry_version_get(struct dentry *dentry);
316bool ovl_is_whiteout(struct dentry *dentry);
317struct file *ovl_path_open(struct path *path, int flags);
318int ovl_copy_up_start(struct dentry *dentry, int flags);
319void ovl_copy_up_end(struct dentry *dentry);
320bool ovl_already_copied_up(struct dentry *dentry, int flags);
321bool ovl_check_origin_xattr(struct ovl_fs *ofs, struct dentry *dentry);
322bool ovl_check_dir_xattr(struct super_block *sb, struct dentry *dentry,
323			 enum ovl_xattr ox);
324int ovl_check_setxattr(struct ovl_fs *ofs, struct dentry *upperdentry,
325		       enum ovl_xattr ox, const void *value, size_t size,
326		       int xerr);
327int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry);
328bool ovl_inuse_trylock(struct dentry *dentry);
329void ovl_inuse_unlock(struct dentry *dentry);
330bool ovl_is_inuse(struct dentry *dentry);
331bool ovl_need_index(struct dentry *dentry);
332int ovl_nlink_start(struct dentry *dentry);
333void ovl_nlink_end(struct dentry *dentry);
334int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
335int ovl_check_metacopy_xattr(struct ovl_fs *ofs, struct dentry *dentry);
336bool ovl_is_metacopy_dentry(struct dentry *dentry);
337char *ovl_get_redirect_xattr(struct ovl_fs *ofs, struct dentry *dentry,
338			     int padding);
339int ovl_sync_status(struct ovl_fs *ofs);
340
341static inline void ovl_set_flag(unsigned long flag, struct inode *inode)
342{
343	set_bit(flag, &OVL_I(inode)->flags);
344}
345
346static inline void ovl_clear_flag(unsigned long flag, struct inode *inode)
347{
348	clear_bit(flag, &OVL_I(inode)->flags);
349}
350
351static inline bool ovl_test_flag(unsigned long flag, struct inode *inode)
352{
353	return test_bit(flag, &OVL_I(inode)->flags);
354}
355
356static inline bool ovl_is_impuredir(struct super_block *sb,
357				    struct dentry *dentry)
358{
359	return ovl_check_dir_xattr(sb, dentry, OVL_XATTR_IMPURE);
360}
361
362/*
363 * With xino=auto, we do best effort to keep all inodes on same st_dev and
364 * d_ino consistent with st_ino.
365 * With xino=on, we do the same effort but we warn if we failed.
366 */
367static inline bool ovl_xino_warn(struct super_block *sb)
368{
369	return OVL_FS(sb)->config.xino == OVL_XINO_ON;
370}
371
372/* All layers on same fs? */
373static inline bool ovl_same_fs(struct super_block *sb)
374{
375	return OVL_FS(sb)->xino_mode == 0;
376}
377
378/* All overlay inodes have same st_dev? */
379static inline bool ovl_same_dev(struct super_block *sb)
380{
381	return OVL_FS(sb)->xino_mode >= 0;
382}
383
384static inline unsigned int ovl_xino_bits(struct super_block *sb)
385{
386	return ovl_same_dev(sb) ? OVL_FS(sb)->xino_mode : 0;
387}
388
389static inline void ovl_inode_lock(struct inode *inode)
390{
391	mutex_lock(&OVL_I(inode)->lock);
392}
393
394static inline int ovl_inode_lock_interruptible(struct inode *inode)
395{
396	return mutex_lock_interruptible(&OVL_I(inode)->lock);
397}
398
399static inline void ovl_inode_unlock(struct inode *inode)
400{
401	mutex_unlock(&OVL_I(inode)->lock);
402}
403
404
405/* namei.c */
406int ovl_check_fb_len(struct ovl_fb *fb, int fb_len);
407
408static inline int ovl_check_fh_len(struct ovl_fh *fh, int fh_len)
409{
410	if (fh_len < sizeof(struct ovl_fh))
411		return -EINVAL;
412
413	return ovl_check_fb_len(&fh->fb, fh_len - OVL_FH_WIRE_OFFSET);
414}
415
416struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh,
417				  struct vfsmount *mnt, bool connected);
418int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
419			struct dentry *upperdentry, struct ovl_path **stackp);
420int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
421		      enum ovl_xattr ox, struct dentry *real, bool is_upper,
422		      bool set);
423struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index);
424int ovl_verify_index(struct ovl_fs *ofs, struct dentry *index);
425int ovl_get_index_name(struct ovl_fs *ofs, struct dentry *origin,
426		       struct qstr *name);
427struct dentry *ovl_get_index_fh(struct ovl_fs *ofs, struct ovl_fh *fh);
428struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper,
429				struct dentry *origin, bool verify);
430int ovl_path_next(int idx, struct dentry *dentry, struct path *path);
431struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
432			  unsigned int flags);
433bool ovl_lower_positive(struct dentry *dentry);
434
435static inline int ovl_verify_origin(struct ovl_fs *ofs, struct dentry *upper,
436				    struct dentry *origin, bool set)
437{
438	return ovl_verify_set_fh(ofs, upper, OVL_XATTR_ORIGIN, origin,
439				 false, set);
440}
441
442static inline int ovl_verify_upper(struct ovl_fs *ofs, struct dentry *index,
443				   struct dentry *upper, bool set)
444{
445	return ovl_verify_set_fh(ofs, index, OVL_XATTR_UPPER, upper, true, set);
446}
447
448/* readdir.c */
449extern const struct file_operations ovl_dir_operations;
450struct file *ovl_dir_real_file(const struct file *file, bool want_upper);
451int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list);
452void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list);
453void ovl_cache_free(struct list_head *list);
454void ovl_dir_cache_free(struct inode *inode);
455int ovl_check_d_type_supported(struct path *realpath);
456int ovl_workdir_cleanup(struct inode *dir, struct vfsmount *mnt,
457			struct dentry *dentry, int level);
458int ovl_indexdir_cleanup(struct ovl_fs *ofs);
459
460/*
461 * Can we iterate real dir directly?
462 *
463 * Non-merge dir may contain whiteouts from a time it was a merge upper, before
464 * lower dir was removed under it and possibly before it was rotated from upper
465 * to lower layer.
466 */
467static inline bool ovl_dir_is_real(struct dentry *dir)
468{
469	return !ovl_test_flag(OVL_WHITEOUTS, d_inode(dir));
470}
471
472/* inode.c */
473int ovl_set_nlink_upper(struct dentry *dentry);
474int ovl_set_nlink_lower(struct dentry *dentry);
475unsigned int ovl_get_nlink(struct ovl_fs *ofs, struct dentry *lowerdentry,
476			   struct dentry *upperdentry,
477			   unsigned int fallback);
478int ovl_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
479		struct iattr *attr);
480int ovl_getattr(struct user_namespace *mnt_userns, const struct path *path,
481		struct kstat *stat, u32 request_mask, unsigned int flags);
482int ovl_permission(struct user_namespace *mnt_userns, struct inode *inode,
483		   int mask);
484int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
485		  const void *value, size_t size, int flags);
486int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
487		  void *value, size_t size);
488ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
489struct posix_acl *ovl_get_acl(struct inode *inode, int type);
490int ovl_update_time(struct inode *inode, struct timespec64 *ts, int flags);
491bool ovl_is_private_xattr(struct super_block *sb, const char *name);
492
493struct ovl_inode_params {
494	struct inode *newinode;
495	struct dentry *upperdentry;
496	struct ovl_path *lowerpath;
497	bool index;
498	unsigned int numlower;
499	char *redirect;
500	struct dentry *lowerdata;
501};
502void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
503		    unsigned long ino, int fsid);
504struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev);
505struct inode *ovl_lookup_inode(struct super_block *sb, struct dentry *real,
506			       bool is_upper);
507bool ovl_lookup_trap_inode(struct super_block *sb, struct dentry *dir);
508struct inode *ovl_get_trap_inode(struct super_block *sb, struct dentry *dir);
509struct inode *ovl_get_inode(struct super_block *sb,
510			    struct ovl_inode_params *oip);
511static inline void ovl_copyattr(struct inode *from, struct inode *to)
512{
513	to->i_uid = from->i_uid;
514	to->i_gid = from->i_gid;
515	to->i_mode = from->i_mode;
516	to->i_atime = from->i_atime;
517	to->i_mtime = from->i_mtime;
518	to->i_ctime = from->i_ctime;
519	i_size_write(to, i_size_read(from));
520}
521
522/* vfs inode flags copied from real to ovl inode */
523#define OVL_COPY_I_FLAGS_MASK	(S_SYNC | S_NOATIME | S_APPEND | S_IMMUTABLE)
524/* vfs inode flags read from overlay.protattr xattr to ovl inode */
525#define OVL_PROT_I_FLAGS_MASK	(S_APPEND | S_IMMUTABLE)
526
527/*
528 * fileattr flags copied from lower to upper inode on copy up.
529 * We cannot copy up immutable/append-only flags, because that would prevent
530 * linking temp inode to upper dir, so we store them in xattr instead.
531 */
532#define OVL_COPY_FS_FLAGS_MASK	(FS_SYNC_FL | FS_NOATIME_FL)
533#define OVL_COPY_FSX_FLAGS_MASK	(FS_XFLAG_SYNC | FS_XFLAG_NOATIME)
534#define OVL_PROT_FS_FLAGS_MASK  (FS_APPEND_FL | FS_IMMUTABLE_FL)
535#define OVL_PROT_FSX_FLAGS_MASK (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE)
536
537void ovl_check_protattr(struct inode *inode, struct dentry *upper);
538int ovl_set_protattr(struct inode *inode, struct dentry *upper,
539		      struct fileattr *fa);
540
541static inline void ovl_copyflags(struct inode *from, struct inode *to)
542{
543	unsigned int mask = OVL_COPY_I_FLAGS_MASK;
544
545	inode_set_flags(to, from->i_flags & mask, mask);
546}
547
548/* dir.c */
549extern const struct inode_operations ovl_dir_inode_operations;
550int ovl_cleanup_and_whiteout(struct ovl_fs *ofs, struct inode *dir,
551			     struct dentry *dentry);
552struct ovl_cattr {
553	dev_t rdev;
554	umode_t mode;
555	const char *link;
556	struct dentry *hardlink;
557};
558
559#define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
560
561struct dentry *ovl_create_real(struct inode *dir, struct dentry *newdentry,
562			       struct ovl_cattr *attr);
563int ovl_cleanup(struct inode *dir, struct dentry *dentry);
564struct dentry *ovl_lookup_temp(struct dentry *workdir);
565struct dentry *ovl_create_temp(struct dentry *workdir, struct ovl_cattr *attr);
566
567/* file.c */
568extern const struct file_operations ovl_file_operations;
569int __init ovl_aio_request_cache_init(void);
570void ovl_aio_request_cache_destroy(void);
571int ovl_real_fileattr_get(struct path *realpath, struct fileattr *fa);
572int ovl_real_fileattr_set(struct path *realpath, struct fileattr *fa);
573int ovl_fileattr_get(struct dentry *dentry, struct fileattr *fa);
574int ovl_fileattr_set(struct user_namespace *mnt_userns,
575		     struct dentry *dentry, struct fileattr *fa);
576
577/* copy_up.c */
578int ovl_copy_up(struct dentry *dentry);
579int ovl_copy_up_with_data(struct dentry *dentry);
580int ovl_maybe_copy_up(struct dentry *dentry, int flags);
581int ovl_copy_xattr(struct super_block *sb, struct dentry *old,
582		   struct dentry *new);
583int ovl_set_attr(struct dentry *upper, struct kstat *stat);
584struct ovl_fh *ovl_encode_real_fh(struct ovl_fs *ofs, struct dentry *real,
585				  bool is_upper);
586int ovl_set_origin(struct ovl_fs *ofs, struct dentry *lower,
587		   struct dentry *upper);
588
589/* export.c */
590extern const struct export_operations ovl_export_operations;
591