1 /* SPDX-License-Identifier: GPL-2.0-only */
4 * Copyright (C) 2011 Novell Inc.
7 #include <linux/kernel.h>
8 #include <linux/uuid.h>
10 #include <linux/fsverity.h>
11 #include <linux/namei.h>
12 #include <linux/posix_acl.h>
13 #include <linux/posix_acl_xattr.h>
14 #include "ovl_entry.h"
17 #define pr_fmt(fmt) "overlayfs: " fmt
20 __OVL_PATH_UPPER
= (1 << 0),
21 __OVL_PATH_MERGE
= (1 << 1),
22 __OVL_PATH_ORIGIN
= (1 << 2),
25 #define OVL_TYPE_UPPER(type) ((type) & __OVL_PATH_UPPER)
26 #define OVL_TYPE_MERGE(type) ((type) & __OVL_PATH_MERGE)
27 #define OVL_TYPE_ORIGIN(type) ((type) & __OVL_PATH_ORIGIN)
29 #define OVL_XATTR_NAMESPACE "overlay."
30 #define OVL_XATTR_TRUSTED_PREFIX XATTR_TRUSTED_PREFIX OVL_XATTR_NAMESPACE
31 #define OVL_XATTR_TRUSTED_PREFIX_LEN (sizeof(OVL_XATTR_TRUSTED_PREFIX) - 1)
32 #define OVL_XATTR_USER_PREFIX XATTR_USER_PREFIX OVL_XATTR_NAMESPACE
33 #define OVL_XATTR_USER_PREFIX_LEN (sizeof(OVL_XATTR_USER_PREFIX) - 1)
35 #define OVL_XATTR_ESCAPE_PREFIX OVL_XATTR_NAMESPACE
36 #define OVL_XATTR_ESCAPE_PREFIX_LEN (sizeof(OVL_XATTR_ESCAPE_PREFIX) - 1)
37 #define OVL_XATTR_ESCAPE_TRUSTED_PREFIX OVL_XATTR_TRUSTED_PREFIX OVL_XATTR_ESCAPE_PREFIX
38 #define OVL_XATTR_ESCAPE_TRUSTED_PREFIX_LEN (sizeof(OVL_XATTR_ESCAPE_TRUSTED_PREFIX) - 1)
39 #define OVL_XATTR_ESCAPE_USER_PREFIX OVL_XATTR_USER_PREFIX OVL_XATTR_ESCAPE_PREFIX
40 #define OVL_XATTR_ESCAPE_USER_PREFIX_LEN (sizeof(OVL_XATTR_ESCAPE_USER_PREFIX) - 1)
57 /* Pure upper dir that may contain non pure upper entries */
59 /* Non-merge dir that may contain whiteout entries */
63 /* Inode number will remain constant over copy up. */
76 OVL_REDIRECT_OFF
, /* "off" mode is never used. In effect */
77 OVL_REDIRECT_FOLLOW
, /* ...it translates to either "follow" */
78 OVL_REDIRECT_NOFOLLOW
, /* ...or "nofollow". */
102 * The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
104 * origin.fh - exported file handle of the lower file
105 * origin.uuid - uuid of the lower filesystem
107 #define OVL_FH_VERSION 0
108 #define OVL_FH_MAGIC 0xfb
110 /* CPU byte order required for fid decoding: */
111 #define OVL_FH_FLAG_BIG_ENDIAN (1 << 0)
112 #define OVL_FH_FLAG_ANY_ENDIAN (1 << 1)
113 /* Is the real inode encoded in fid an upper inode? */
114 #define OVL_FH_FLAG_PATH_UPPER (1 << 2)
116 #define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN | \
117 OVL_FH_FLAG_PATH_UPPER)
119 #if defined(__LITTLE_ENDIAN)
120 #define OVL_FH_FLAG_CPU_ENDIAN 0
121 #elif defined(__BIG_ENDIAN)
122 #define OVL_FH_FLAG_CPU_ENDIAN OVL_FH_FLAG_BIG_ENDIAN
124 #error Endianness not defined
127 /* The type used to be returned by overlay exportfs for misaligned fid */
128 #define OVL_FILEID_V0 0xfb
129 /* The type returned by overlay exportfs for 32bit aligned fid */
130 #define OVL_FILEID_V1 0xf8
132 /* On-disk format for "origin" file handle */
136 u8 len
; /* size of this header + size of fid */
137 u8 flags
; /* OVL_FH_FLAG_* */
138 u8 type
; /* fid_type of fid */
139 uuid_t uuid
; /* uuid of filesystem */
140 u32 fid
[]; /* file identifier should be 32bit aligned in-memory */
143 /* In-memory and on-wire format for overlay file handle */
145 u8 padding
[3]; /* make sure fb.fid is 32bit aligned */
148 DECLARE_FLEX_ARRAY(u8
, buf
);
152 #define OVL_FH_WIRE_OFFSET offsetof(struct ovl_fh, fb)
153 #define OVL_FH_LEN(fh) (OVL_FH_WIRE_OFFSET + (fh)->fb.len)
154 #define OVL_FH_FID_OFFSET (OVL_FH_WIRE_OFFSET + \
155 offsetof(struct ovl_fb, fid))
157 /* On-disk format for "metacopy" xattr (if non-zero size) */
158 struct ovl_metacopy
{
160 u8 len
; /* size of this header + used digest bytes */
162 u8 digest_algo
; /* FS_VERITY_HASH_ALG_* constant, 0 for no digest */
163 u8 digest
[FS_VERITY_MAX_DIGEST_SIZE
]; /* Only the used part on disk */
166 #define OVL_METACOPY_MAX_SIZE (sizeof(struct ovl_metacopy))
167 #define OVL_METACOPY_MIN_SIZE (OVL_METACOPY_MAX_SIZE - FS_VERITY_MAX_DIGEST_SIZE)
168 #define OVL_METACOPY_INIT { 0, OVL_METACOPY_MIN_SIZE }
170 static inline int ovl_metadata_digest_size(const struct ovl_metacopy
*metacopy
)
172 if (metacopy
->len
< OVL_METACOPY_MIN_SIZE
)
174 return (int)metacopy
->len
- OVL_METACOPY_MIN_SIZE
;
177 extern const char *const ovl_xattr_table
[][2];
178 static inline const char *ovl_xattr(struct ovl_fs
*ofs
, enum ovl_xattr ox
)
180 return ovl_xattr_table
[ox
][ofs
->config
.userxattr
];
184 * When changing ownership of an upper object map the intended ownership
185 * according to the upper layer's idmapping. When an upper mount idmaps files
186 * that are stored on-disk as owned by id 1001 to id 1000 this means stat on
187 * this object will report it as being owned by id 1000 when calling stat via
189 * In order to change ownership of an object so stat reports id 1000 when
190 * called on an idmapped upper mount the value written to disk - i.e., the
191 * value stored in ia_*id - must 1001. The mount mapping helper will thus take
192 * care to map 1000 to 1001.
193 * The mnt idmapping helpers are nops if the upper layer isn't idmapped.
195 static inline int ovl_do_notify_change(struct ovl_fs
*ofs
,
196 struct dentry
*upperdentry
,
199 return notify_change(ovl_upper_mnt_idmap(ofs
), upperdentry
, attr
, NULL
);
202 static inline int ovl_do_rmdir(struct ovl_fs
*ofs
,
203 struct inode
*dir
, struct dentry
*dentry
)
205 int err
= vfs_rmdir(ovl_upper_mnt_idmap(ofs
), dir
, dentry
);
207 pr_debug("rmdir(%pd2) = %i\n", dentry
, err
);
211 static inline int ovl_do_unlink(struct ovl_fs
*ofs
, struct inode
*dir
,
212 struct dentry
*dentry
)
214 int err
= vfs_unlink(ovl_upper_mnt_idmap(ofs
), dir
, dentry
, NULL
);
216 pr_debug("unlink(%pd2) = %i\n", dentry
, err
);
220 static inline int ovl_do_link(struct ovl_fs
*ofs
, struct dentry
*old_dentry
,
221 struct inode
*dir
, struct dentry
*new_dentry
)
223 int err
= vfs_link(old_dentry
, ovl_upper_mnt_idmap(ofs
), dir
,
226 pr_debug("link(%pd2, %pd2) = %i\n", old_dentry
, new_dentry
, err
);
230 static inline int ovl_do_create(struct ovl_fs
*ofs
,
231 struct inode
*dir
, struct dentry
*dentry
,
234 int err
= vfs_create(ovl_upper_mnt_idmap(ofs
), dir
, dentry
, mode
, true);
236 pr_debug("create(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
240 static inline int ovl_do_mkdir(struct ovl_fs
*ofs
,
241 struct inode
*dir
, struct dentry
*dentry
,
244 int err
= vfs_mkdir(ovl_upper_mnt_idmap(ofs
), dir
, dentry
, mode
);
245 pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
249 static inline int ovl_do_mknod(struct ovl_fs
*ofs
,
250 struct inode
*dir
, struct dentry
*dentry
,
251 umode_t mode
, dev_t dev
)
253 int err
= vfs_mknod(ovl_upper_mnt_idmap(ofs
), dir
, dentry
, mode
, dev
);
255 pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry
, mode
, dev
, err
);
259 static inline int ovl_do_symlink(struct ovl_fs
*ofs
,
260 struct inode
*dir
, struct dentry
*dentry
,
263 int err
= vfs_symlink(ovl_upper_mnt_idmap(ofs
), dir
, dentry
, oldname
);
265 pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname
, dentry
, err
);
269 static inline ssize_t
ovl_do_getxattr(const struct path
*path
, const char *name
,
270 void *value
, size_t size
)
274 WARN_ON(path
->dentry
->d_sb
!= path
->mnt
->mnt_sb
);
276 err
= vfs_getxattr(mnt_idmap(path
->mnt
), path
->dentry
,
278 len
= (value
&& err
> 0) ? err
: 0;
280 pr_debug("getxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
281 path
->dentry
, name
, min(len
, 48), value
, size
, err
);
285 static inline ssize_t
ovl_getxattr_upper(struct ovl_fs
*ofs
,
286 struct dentry
*upperdentry
,
287 enum ovl_xattr ox
, void *value
,
290 struct path upperpath
= {
291 .dentry
= upperdentry
,
292 .mnt
= ovl_upper_mnt(ofs
),
295 return ovl_do_getxattr(&upperpath
, ovl_xattr(ofs
, ox
), value
, size
);
298 static inline ssize_t
ovl_path_getxattr(struct ovl_fs
*ofs
,
299 const struct path
*path
,
300 enum ovl_xattr ox
, void *value
,
303 return ovl_do_getxattr(path
, ovl_xattr(ofs
, ox
), value
, size
);
306 static inline int ovl_do_setxattr(struct ovl_fs
*ofs
, struct dentry
*dentry
,
307 const char *name
, const void *value
,
308 size_t size
, int flags
)
310 int err
= vfs_setxattr(ovl_upper_mnt_idmap(ofs
), dentry
, name
,
313 pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, %d) = %i\n",
314 dentry
, name
, min((int)size
, 48), value
, size
, flags
, err
);
318 static inline int ovl_setxattr(struct ovl_fs
*ofs
, struct dentry
*dentry
,
319 enum ovl_xattr ox
, const void *value
,
322 return ovl_do_setxattr(ofs
, dentry
, ovl_xattr(ofs
, ox
), value
, size
, 0);
325 static inline int ovl_do_removexattr(struct ovl_fs
*ofs
, struct dentry
*dentry
,
328 int err
= vfs_removexattr(ovl_upper_mnt_idmap(ofs
), dentry
, name
);
329 pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry
, name
, err
);
333 static inline int ovl_removexattr(struct ovl_fs
*ofs
, struct dentry
*dentry
,
336 return ovl_do_removexattr(ofs
, dentry
, ovl_xattr(ofs
, ox
));
339 static inline int ovl_do_set_acl(struct ovl_fs
*ofs
, struct dentry
*dentry
,
340 const char *acl_name
, struct posix_acl
*acl
)
342 return vfs_set_acl(ovl_upper_mnt_idmap(ofs
), dentry
, acl_name
, acl
);
345 static inline int ovl_do_remove_acl(struct ovl_fs
*ofs
, struct dentry
*dentry
,
346 const char *acl_name
)
348 return vfs_remove_acl(ovl_upper_mnt_idmap(ofs
), dentry
, acl_name
);
351 static inline int ovl_do_rename(struct ovl_fs
*ofs
, struct inode
*olddir
,
352 struct dentry
*olddentry
, struct inode
*newdir
,
353 struct dentry
*newdentry
, unsigned int flags
)
356 struct renamedata rd
= {
357 .old_mnt_idmap
= ovl_upper_mnt_idmap(ofs
),
359 .old_dentry
= olddentry
,
360 .new_mnt_idmap
= ovl_upper_mnt_idmap(ofs
),
362 .new_dentry
= newdentry
,
366 pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry
, newdentry
, flags
);
367 err
= vfs_rename(&rd
);
369 pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
370 olddentry
, newdentry
, err
);
375 static inline int ovl_do_whiteout(struct ovl_fs
*ofs
,
376 struct inode
*dir
, struct dentry
*dentry
)
378 int err
= vfs_whiteout(ovl_upper_mnt_idmap(ofs
), dir
, dentry
);
379 pr_debug("whiteout(%pd2) = %i\n", dentry
, err
);
383 static inline struct file
*ovl_do_tmpfile(struct ovl_fs
*ofs
,
384 struct dentry
*dentry
, umode_t mode
)
386 struct path path
= { .mnt
= ovl_upper_mnt(ofs
), .dentry
= dentry
};
387 struct file
*file
= kernel_tmpfile_open(ovl_upper_mnt_idmap(ofs
), &path
,
388 mode
, O_LARGEFILE
| O_WRONLY
,
390 int err
= PTR_ERR_OR_ZERO(file
);
392 pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
396 static inline struct dentry
*ovl_lookup_upper(struct ovl_fs
*ofs
,
398 struct dentry
*base
, int len
)
400 return lookup_one(ovl_upper_mnt_idmap(ofs
), name
, base
, len
);
403 static inline bool ovl_open_flags_need_copy_up(int flags
)
408 return ((OPEN_FMODE(flags
) & FMODE_WRITE
) || (flags
& O_TRUNC
));
412 int ovl_get_write_access(struct dentry
*dentry
);
413 void ovl_put_write_access(struct dentry
*dentry
);
414 void ovl_start_write(struct dentry
*dentry
);
415 void ovl_end_write(struct dentry
*dentry
);
416 int ovl_want_write(struct dentry
*dentry
);
417 void ovl_drop_write(struct dentry
*dentry
);
418 struct dentry
*ovl_workdir(struct dentry
*dentry
);
419 const struct cred
*ovl_override_creds(struct super_block
*sb
);
420 int ovl_can_decode_fh(struct super_block
*sb
);
421 struct dentry
*ovl_indexdir(struct super_block
*sb
);
422 bool ovl_index_all(struct super_block
*sb
);
423 bool ovl_verify_lower(struct super_block
*sb
);
424 struct ovl_path
*ovl_stack_alloc(unsigned int n
);
425 void ovl_stack_cpy(struct ovl_path
*dst
, struct ovl_path
*src
, unsigned int n
);
426 void ovl_stack_put(struct ovl_path
*stack
, unsigned int n
);
427 void ovl_stack_free(struct ovl_path
*stack
, unsigned int n
);
428 struct ovl_entry
*ovl_alloc_entry(unsigned int numlower
);
429 void ovl_free_entry(struct ovl_entry
*oe
);
430 bool ovl_dentry_remote(struct dentry
*dentry
);
431 void ovl_dentry_update_reval(struct dentry
*dentry
, struct dentry
*realdentry
);
432 void ovl_dentry_init_reval(struct dentry
*dentry
, struct dentry
*upperdentry
,
433 struct ovl_entry
*oe
);
434 void ovl_dentry_init_flags(struct dentry
*dentry
, struct dentry
*upperdentry
,
435 struct ovl_entry
*oe
, unsigned int mask
);
436 bool ovl_dentry_weird(struct dentry
*dentry
);
437 enum ovl_path_type
ovl_path_type(struct dentry
*dentry
);
438 void ovl_path_upper(struct dentry
*dentry
, struct path
*path
);
439 void ovl_path_lower(struct dentry
*dentry
, struct path
*path
);
440 void ovl_path_lowerdata(struct dentry
*dentry
, struct path
*path
);
441 struct inode
*ovl_i_path_real(struct inode
*inode
, struct path
*path
);
442 enum ovl_path_type
ovl_path_real(struct dentry
*dentry
, struct path
*path
);
443 enum ovl_path_type
ovl_path_realdata(struct dentry
*dentry
, struct path
*path
);
444 struct dentry
*ovl_dentry_upper(struct dentry
*dentry
);
445 struct dentry
*ovl_dentry_lower(struct dentry
*dentry
);
446 struct dentry
*ovl_dentry_lowerdata(struct dentry
*dentry
);
447 int ovl_dentry_set_lowerdata(struct dentry
*dentry
, struct ovl_path
*datapath
);
448 const struct ovl_layer
*ovl_i_layer_lower(struct inode
*inode
);
449 const struct ovl_layer
*ovl_layer_lower(struct dentry
*dentry
);
450 struct dentry
*ovl_dentry_real(struct dentry
*dentry
);
451 struct dentry
*ovl_i_dentry_upper(struct inode
*inode
);
452 struct inode
*ovl_inode_upper(struct inode
*inode
);
453 struct inode
*ovl_inode_lower(struct inode
*inode
);
454 struct inode
*ovl_inode_lowerdata(struct inode
*inode
);
455 struct inode
*ovl_inode_real(struct inode
*inode
);
456 struct inode
*ovl_inode_realdata(struct inode
*inode
);
457 const char *ovl_lowerdata_redirect(struct inode
*inode
);
458 struct ovl_dir_cache
*ovl_dir_cache(struct inode
*inode
);
459 void ovl_set_dir_cache(struct inode
*inode
, struct ovl_dir_cache
*cache
);
460 void ovl_dentry_set_flag(unsigned long flag
, struct dentry
*dentry
);
461 void ovl_dentry_clear_flag(unsigned long flag
, struct dentry
*dentry
);
462 bool ovl_dentry_test_flag(unsigned long flag
, struct dentry
*dentry
);
463 bool ovl_dentry_is_opaque(struct dentry
*dentry
);
464 bool ovl_dentry_is_whiteout(struct dentry
*dentry
);
465 void ovl_dentry_set_opaque(struct dentry
*dentry
);
466 bool ovl_dentry_has_upper_alias(struct dentry
*dentry
);
467 void ovl_dentry_set_upper_alias(struct dentry
*dentry
);
468 bool ovl_dentry_needs_data_copy_up(struct dentry
*dentry
, int flags
);
469 bool ovl_dentry_needs_data_copy_up_locked(struct dentry
*dentry
, int flags
);
470 bool ovl_has_upperdata(struct inode
*inode
);
471 void ovl_set_upperdata(struct inode
*inode
);
472 const char *ovl_dentry_get_redirect(struct dentry
*dentry
);
473 void ovl_dentry_set_redirect(struct dentry
*dentry
, const char *redirect
);
474 void ovl_inode_update(struct inode
*inode
, struct dentry
*upperdentry
);
475 void ovl_dir_modified(struct dentry
*dentry
, bool impurity
);
476 u64
ovl_inode_version_get(struct inode
*inode
);
477 bool ovl_is_whiteout(struct dentry
*dentry
);
478 bool ovl_path_is_whiteout(struct ovl_fs
*ofs
, const struct path
*path
);
479 struct file
*ovl_path_open(const struct path
*path
, int flags
);
480 int ovl_copy_up_start(struct dentry
*dentry
, int flags
);
481 void ovl_copy_up_end(struct dentry
*dentry
);
482 bool ovl_already_copied_up(struct dentry
*dentry
, int flags
);
483 bool ovl_path_check_dir_xattr(struct ovl_fs
*ofs
, const struct path
*path
,
485 bool ovl_path_check_origin_xattr(struct ovl_fs
*ofs
, const struct path
*path
);
486 bool ovl_path_check_xwhiteout_xattr(struct ovl_fs
*ofs
, const struct path
*path
);
487 bool ovl_path_check_xwhiteouts_xattr(struct ovl_fs
*ofs
, const struct path
*path
);
488 bool ovl_init_uuid_xattr(struct super_block
*sb
, struct ovl_fs
*ofs
,
489 const struct path
*upperpath
);
491 static inline bool ovl_upper_is_whiteout(struct ovl_fs
*ofs
,
492 struct dentry
*upperdentry
)
494 struct path upperpath
= {
495 .dentry
= upperdentry
,
496 .mnt
= ovl_upper_mnt(ofs
),
498 return ovl_path_is_whiteout(ofs
, &upperpath
);
501 static inline bool ovl_check_origin_xattr(struct ovl_fs
*ofs
,
502 struct dentry
*upperdentry
)
504 struct path upperpath
= {
505 .dentry
= upperdentry
,
506 .mnt
= ovl_upper_mnt(ofs
),
508 return ovl_path_check_origin_xattr(ofs
, &upperpath
);
511 int ovl_check_setxattr(struct ovl_fs
*ofs
, struct dentry
*upperdentry
,
512 enum ovl_xattr ox
, const void *value
, size_t size
,
514 int ovl_set_impure(struct dentry
*dentry
, struct dentry
*upperdentry
);
515 bool ovl_inuse_trylock(struct dentry
*dentry
);
516 void ovl_inuse_unlock(struct dentry
*dentry
);
517 bool ovl_is_inuse(struct dentry
*dentry
);
518 bool ovl_need_index(struct dentry
*dentry
);
519 int ovl_nlink_start(struct dentry
*dentry
);
520 void ovl_nlink_end(struct dentry
*dentry
);
521 int ovl_lock_rename_workdir(struct dentry
*workdir
, struct dentry
*upperdir
);
522 int ovl_check_metacopy_xattr(struct ovl_fs
*ofs
, const struct path
*path
,
523 struct ovl_metacopy
*data
);
524 int ovl_set_metacopy_xattr(struct ovl_fs
*ofs
, struct dentry
*d
,
525 struct ovl_metacopy
*metacopy
);
526 bool ovl_is_metacopy_dentry(struct dentry
*dentry
);
527 char *ovl_get_redirect_xattr(struct ovl_fs
*ofs
, const struct path
*path
, int padding
);
528 int ovl_ensure_verity_loaded(struct path
*path
);
529 int ovl_get_verity_xattr(struct ovl_fs
*ofs
, const struct path
*path
,
530 u8
*digest_buf
, int *buf_length
);
531 int ovl_validate_verity(struct ovl_fs
*ofs
,
532 struct path
*metapath
,
533 struct path
*datapath
);
534 int ovl_get_verity_digest(struct ovl_fs
*ofs
, struct path
*src
,
535 struct ovl_metacopy
*metacopy
);
536 int ovl_sync_status(struct ovl_fs
*ofs
);
538 static inline void ovl_set_flag(unsigned long flag
, struct inode
*inode
)
540 set_bit(flag
, &OVL_I(inode
)->flags
);
543 static inline void ovl_clear_flag(unsigned long flag
, struct inode
*inode
)
545 clear_bit(flag
, &OVL_I(inode
)->flags
);
548 static inline bool ovl_test_flag(unsigned long flag
, struct inode
*inode
)
550 return test_bit(flag
, &OVL_I(inode
)->flags
);
553 static inline bool ovl_is_impuredir(struct super_block
*sb
,
554 struct dentry
*upperdentry
)
556 struct ovl_fs
*ofs
= OVL_FS(sb
);
557 struct path upperpath
= {
558 .dentry
= upperdentry
,
559 .mnt
= ovl_upper_mnt(ofs
),
562 return ovl_path_check_dir_xattr(ofs
, &upperpath
, OVL_XATTR_IMPURE
);
565 static inline bool ovl_redirect_follow(struct ovl_fs
*ofs
)
567 return ofs
->config
.redirect_mode
!= OVL_REDIRECT_NOFOLLOW
;
570 static inline bool ovl_redirect_dir(struct ovl_fs
*ofs
)
572 return ofs
->config
.redirect_mode
== OVL_REDIRECT_ON
;
575 static inline bool ovl_origin_uuid(struct ovl_fs
*ofs
)
577 return ofs
->config
.uuid
!= OVL_UUID_OFF
;
580 static inline bool ovl_has_fsid(struct ovl_fs
*ofs
)
582 return ofs
->config
.uuid
== OVL_UUID_ON
||
583 ofs
->config
.uuid
== OVL_UUID_AUTO
;
587 * With xino=auto, we do best effort to keep all inodes on same st_dev and
588 * d_ino consistent with st_ino.
589 * With xino=on, we do the same effort but we warn if we failed.
591 static inline bool ovl_xino_warn(struct ovl_fs
*ofs
)
593 return ofs
->config
.xino
== OVL_XINO_ON
;
597 * To avoid regressions in existing setups with overlay lower offline changes,
598 * we allow lower changes only if none of the new features are used.
600 static inline bool ovl_allow_offline_changes(struct ovl_fs
*ofs
)
602 return (!ofs
->config
.index
&& !ofs
->config
.metacopy
&&
603 !ovl_redirect_dir(ofs
) && !ovl_xino_warn(ofs
));
606 /* All layers on same fs? */
607 static inline bool ovl_same_fs(struct ovl_fs
*ofs
)
609 return ofs
->xino_mode
== 0;
612 /* All overlay inodes have same st_dev? */
613 static inline bool ovl_same_dev(struct ovl_fs
*ofs
)
615 return ofs
->xino_mode
>= 0;
618 static inline unsigned int ovl_xino_bits(struct ovl_fs
*ofs
)
620 return ovl_same_dev(ofs
) ? ofs
->xino_mode
: 0;
623 static inline void ovl_inode_lock(struct inode
*inode
)
625 mutex_lock(&OVL_I(inode
)->lock
);
628 static inline int ovl_inode_lock_interruptible(struct inode
*inode
)
630 return mutex_lock_interruptible(&OVL_I(inode
)->lock
);
633 static inline void ovl_inode_unlock(struct inode
*inode
)
635 mutex_unlock(&OVL_I(inode
)->lock
);
640 int ovl_check_fb_len(struct ovl_fb
*fb
, int fb_len
);
642 static inline int ovl_check_fh_len(struct ovl_fh
*fh
, int fh_len
)
644 if (fh_len
< sizeof(struct ovl_fh
))
647 return ovl_check_fb_len(&fh
->fb
, fh_len
- OVL_FH_WIRE_OFFSET
);
650 struct dentry
*ovl_decode_real_fh(struct ovl_fs
*ofs
, struct ovl_fh
*fh
,
651 struct vfsmount
*mnt
, bool connected
);
652 int ovl_check_origin_fh(struct ovl_fs
*ofs
, struct ovl_fh
*fh
, bool connected
,
653 struct dentry
*upperdentry
, struct ovl_path
**stackp
);
654 int ovl_verify_set_fh(struct ovl_fs
*ofs
, struct dentry
*dentry
,
655 enum ovl_xattr ox
, const struct ovl_fh
*fh
,
656 bool is_upper
, bool set
);
657 int ovl_verify_origin_xattr(struct ovl_fs
*ofs
, struct dentry
*dentry
,
658 enum ovl_xattr ox
, struct dentry
*real
,
659 bool is_upper
, bool set
);
660 struct dentry
*ovl_index_upper(struct ovl_fs
*ofs
, struct dentry
*index
,
662 int ovl_verify_index(struct ovl_fs
*ofs
, struct dentry
*index
);
663 int ovl_get_index_name_fh(const struct ovl_fh
*fh
, struct qstr
*name
);
664 int ovl_get_index_name(struct ovl_fs
*ofs
, struct dentry
*origin
,
666 struct dentry
*ovl_get_index_fh(struct ovl_fs
*ofs
, struct ovl_fh
*fh
);
667 struct dentry
*ovl_lookup_index(struct ovl_fs
*ofs
, struct dentry
*upper
,
668 struct dentry
*origin
, bool verify
);
669 int ovl_path_next(int idx
, struct dentry
*dentry
, struct path
*path
);
670 int ovl_verify_lowerdata(struct dentry
*dentry
);
671 struct dentry
*ovl_lookup(struct inode
*dir
, struct dentry
*dentry
,
673 bool ovl_lower_positive(struct dentry
*dentry
);
675 static inline int ovl_verify_origin_fh(struct ovl_fs
*ofs
, struct dentry
*upper
,
676 const struct ovl_fh
*fh
, bool set
)
678 return ovl_verify_set_fh(ofs
, upper
, OVL_XATTR_ORIGIN
, fh
, false, set
);
681 static inline int ovl_verify_origin(struct ovl_fs
*ofs
, struct dentry
*upper
,
682 struct dentry
*origin
, bool set
)
684 return ovl_verify_origin_xattr(ofs
, upper
, OVL_XATTR_ORIGIN
, origin
,
688 static inline int ovl_verify_upper(struct ovl_fs
*ofs
, struct dentry
*index
,
689 struct dentry
*upper
, bool set
)
691 return ovl_verify_origin_xattr(ofs
, index
, OVL_XATTR_UPPER
, upper
,
696 extern const struct file_operations ovl_dir_operations
;
697 struct file
*ovl_dir_real_file(const struct file
*file
, bool want_upper
);
698 int ovl_check_empty_dir(struct dentry
*dentry
, struct list_head
*list
);
699 void ovl_cleanup_whiteouts(struct ovl_fs
*ofs
, struct dentry
*upper
,
700 struct list_head
*list
);
701 void ovl_cache_free(struct list_head
*list
);
702 void ovl_dir_cache_free(struct inode
*inode
);
703 int ovl_check_d_type_supported(const struct path
*realpath
);
704 int ovl_workdir_cleanup(struct ovl_fs
*ofs
, struct inode
*dir
,
705 struct vfsmount
*mnt
, struct dentry
*dentry
, int level
);
706 int ovl_indexdir_cleanup(struct ovl_fs
*ofs
);
709 * Can we iterate real dir directly?
711 * Non-merge dir may contain whiteouts from a time it was a merge upper, before
712 * lower dir was removed under it and possibly before it was rotated from upper
715 static inline bool ovl_dir_is_real(struct inode
*dir
)
717 return !ovl_test_flag(OVL_WHITEOUTS
, dir
);
721 int ovl_set_nlink_upper(struct dentry
*dentry
);
722 int ovl_set_nlink_lower(struct dentry
*dentry
);
723 unsigned int ovl_get_nlink(struct ovl_fs
*ofs
, struct dentry
*lowerdentry
,
724 struct dentry
*upperdentry
,
725 unsigned int fallback
);
726 int ovl_permission(struct mnt_idmap
*idmap
, struct inode
*inode
,
729 #ifdef CONFIG_FS_POSIX_ACL
730 struct posix_acl
*do_ovl_get_acl(struct mnt_idmap
*idmap
,
731 struct inode
*inode
, int type
,
732 bool rcu
, bool noperm
);
733 static inline struct posix_acl
*ovl_get_inode_acl(struct inode
*inode
, int type
,
736 return do_ovl_get_acl(&nop_mnt_idmap
, inode
, type
, rcu
, true);
738 static inline struct posix_acl
*ovl_get_acl(struct mnt_idmap
*idmap
,
739 struct dentry
*dentry
, int type
)
741 return do_ovl_get_acl(idmap
, d_inode(dentry
), type
, false, false);
743 int ovl_set_acl(struct mnt_idmap
*idmap
, struct dentry
*dentry
,
744 struct posix_acl
*acl
, int type
);
745 struct posix_acl
*ovl_get_acl_path(const struct path
*path
,
746 const char *acl_name
, bool noperm
);
748 #define ovl_get_inode_acl NULL
749 #define ovl_get_acl NULL
750 #define ovl_set_acl NULL
751 static inline struct posix_acl
*ovl_get_acl_path(const struct path
*path
,
752 const char *acl_name
,
759 int ovl_update_time(struct inode
*inode
, int flags
);
760 bool ovl_is_private_xattr(struct super_block
*sb
, const char *name
);
762 struct ovl_inode_params
{
763 struct inode
*newinode
;
764 struct dentry
*upperdentry
;
765 struct ovl_entry
*oe
;
768 char *lowerdata_redirect
;
770 void ovl_inode_init(struct inode
*inode
, struct ovl_inode_params
*oip
,
771 unsigned long ino
, int fsid
);
772 struct inode
*ovl_new_inode(struct super_block
*sb
, umode_t mode
, dev_t rdev
);
773 struct inode
*ovl_lookup_inode(struct super_block
*sb
, struct dentry
*real
,
775 bool ovl_lookup_trap_inode(struct super_block
*sb
, struct dentry
*dir
);
776 struct inode
*ovl_get_trap_inode(struct super_block
*sb
, struct dentry
*dir
);
777 struct inode
*ovl_get_inode(struct super_block
*sb
,
778 struct ovl_inode_params
*oip
);
779 void ovl_copyattr(struct inode
*to
);
781 /* vfs inode flags copied from real to ovl inode */
782 #define OVL_COPY_I_FLAGS_MASK (S_SYNC | S_NOATIME | S_APPEND | S_IMMUTABLE)
783 /* vfs inode flags read from overlay.protattr xattr to ovl inode */
784 #define OVL_PROT_I_FLAGS_MASK (S_APPEND | S_IMMUTABLE)
787 * fileattr flags copied from lower to upper inode on copy up.
788 * We cannot copy up immutable/append-only flags, because that would prevent
789 * linking temp inode to upper dir, so we store them in xattr instead.
791 #define OVL_COPY_FS_FLAGS_MASK (FS_SYNC_FL | FS_NOATIME_FL)
792 #define OVL_COPY_FSX_FLAGS_MASK (FS_XFLAG_SYNC | FS_XFLAG_NOATIME)
793 #define OVL_PROT_FS_FLAGS_MASK (FS_APPEND_FL | FS_IMMUTABLE_FL)
794 #define OVL_PROT_FSX_FLAGS_MASK (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE)
796 void ovl_check_protattr(struct inode
*inode
, struct dentry
*upper
);
797 int ovl_set_protattr(struct inode
*inode
, struct dentry
*upper
,
798 struct fileattr
*fa
);
800 static inline void ovl_copyflags(struct inode
*from
, struct inode
*to
)
802 unsigned int mask
= OVL_COPY_I_FLAGS_MASK
;
804 inode_set_flags(to
, from
->i_flags
& mask
, mask
);
808 extern const struct inode_operations ovl_dir_inode_operations
;
809 int ovl_cleanup_and_whiteout(struct ovl_fs
*ofs
, struct inode
*dir
,
810 struct dentry
*dentry
);
815 struct dentry
*hardlink
;
818 #define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
820 int ovl_mkdir_real(struct ovl_fs
*ofs
, struct inode
*dir
,
821 struct dentry
**newdentry
, umode_t mode
);
822 struct dentry
*ovl_create_real(struct ovl_fs
*ofs
,
823 struct inode
*dir
, struct dentry
*newdentry
,
824 struct ovl_cattr
*attr
);
825 int ovl_cleanup(struct ovl_fs
*ofs
, struct inode
*dir
, struct dentry
*dentry
);
826 struct dentry
*ovl_lookup_temp(struct ovl_fs
*ofs
, struct dentry
*workdir
);
827 struct dentry
*ovl_create_temp(struct ovl_fs
*ofs
, struct dentry
*workdir
,
828 struct ovl_cattr
*attr
);
831 extern const struct file_operations ovl_file_operations
;
832 int __init
ovl_aio_request_cache_init(void);
833 void ovl_aio_request_cache_destroy(void);
834 int ovl_real_fileattr_get(const struct path
*realpath
, struct fileattr
*fa
);
835 int ovl_real_fileattr_set(const struct path
*realpath
, struct fileattr
*fa
);
836 int ovl_fileattr_get(struct dentry
*dentry
, struct fileattr
*fa
);
837 int ovl_fileattr_set(struct mnt_idmap
*idmap
,
838 struct dentry
*dentry
, struct fileattr
*fa
);
841 int ovl_copy_up(struct dentry
*dentry
);
842 int ovl_copy_up_with_data(struct dentry
*dentry
);
843 int ovl_maybe_copy_up(struct dentry
*dentry
, int flags
);
844 int ovl_copy_xattr(struct super_block
*sb
, const struct path
*path
, struct dentry
*new);
845 int ovl_set_attr(struct ovl_fs
*ofs
, struct dentry
*upper
, struct kstat
*stat
);
846 struct ovl_fh
*ovl_encode_real_fh(struct ovl_fs
*ofs
, struct dentry
*real
,
848 struct ovl_fh
*ovl_get_origin_fh(struct ovl_fs
*ofs
, struct dentry
*origin
);
849 int ovl_set_origin_fh(struct ovl_fs
*ofs
, const struct ovl_fh
*fh
,
850 struct dentry
*upper
);
853 extern const struct export_operations ovl_export_operations
;
854 extern const struct export_operations ovl_export_fid_operations
;
857 int ovl_fill_super(struct super_block
*sb
, struct fs_context
*fc
);
859 /* Will this overlay be forced to mount/remount ro? */
860 static inline bool ovl_force_readonly(struct ovl_fs
*ofs
)
862 return (!ovl_upper_mnt(ofs
) || !ofs
->workdir
);
867 const struct xattr_handler
* const *ovl_xattr_handlers(struct ovl_fs
*ofs
);
868 int ovl_setattr(struct mnt_idmap
*idmap
, struct dentry
*dentry
,
870 int ovl_getattr(struct mnt_idmap
*idmap
, const struct path
*path
,
871 struct kstat
*stat
, u32 request_mask
, unsigned int flags
);
872 ssize_t
ovl_listxattr(struct dentry
*dentry
, char *list
, size_t size
);