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));
411 static inline int ovl_do_getattr(const struct path *path, struct kstat *stat,
412 u32 request_mask, unsigned int flags)
414 if (flags & AT_GETATTR_NOSEC)
415 return vfs_getattr_nosec(path, stat, request_mask, flags);
416 return vfs_getattr(path, stat, request_mask, flags);
420 int ovl_get_write_access(struct dentry *dentry);
421 void ovl_put_write_access(struct dentry *dentry);
422 void ovl_start_write(struct dentry *dentry);
423 void ovl_end_write(struct dentry *dentry);
424 int ovl_want_write(struct dentry *dentry);
425 void ovl_drop_write(struct dentry *dentry);
426 struct dentry *ovl_workdir(struct dentry *dentry);
427 const struct cred *ovl_override_creds(struct super_block *sb);
428 int ovl_can_decode_fh(struct super_block *sb);
429 struct dentry *ovl_indexdir(struct super_block *sb);
430 bool ovl_index_all(struct super_block *sb);
431 bool ovl_verify_lower(struct super_block *sb);
432 struct ovl_path *ovl_stack_alloc(unsigned int n);
433 void ovl_stack_cpy(struct ovl_path *dst, struct ovl_path *src, unsigned int n);
434 void ovl_stack_put(struct ovl_path *stack, unsigned int n);
435 void ovl_stack_free(struct ovl_path *stack, unsigned int n);
436 struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
437 void ovl_free_entry(struct ovl_entry *oe);
438 bool ovl_dentry_remote(struct dentry *dentry);
439 void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry);
440 void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry,
441 struct ovl_entry *oe);
442 void ovl_dentry_init_flags(struct dentry *dentry, struct dentry *upperdentry,
443 struct ovl_entry *oe, unsigned int mask);
444 bool ovl_dentry_weird(struct dentry *dentry);
445 enum ovl_path_type ovl_path_type(struct dentry *dentry);
446 void ovl_path_upper(struct dentry *dentry, struct path *path);
447 void ovl_path_lower(struct dentry *dentry, struct path *path);
448 void ovl_path_lowerdata(struct dentry *dentry, struct path *path);
449 struct inode *ovl_i_path_real(struct inode *inode, struct path *path);
450 enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
451 enum ovl_path_type ovl_path_realdata(struct dentry *dentry, struct path *path);
452 struct dentry *ovl_dentry_upper(struct dentry *dentry);
453 struct dentry *ovl_dentry_lower(struct dentry *dentry);
454 struct dentry *ovl_dentry_lowerdata(struct dentry *dentry);
455 int ovl_dentry_set_lowerdata(struct dentry *dentry, struct ovl_path *datapath);
456 const struct ovl_layer *ovl_i_layer_lower(struct inode *inode);
457 const struct ovl_layer *ovl_layer_lower(struct dentry *dentry);
458 struct dentry *ovl_dentry_real(struct dentry *dentry);
459 struct dentry *ovl_i_dentry_upper(struct inode *inode);
460 struct inode *ovl_inode_upper(struct inode *inode);
461 struct inode *ovl_inode_lower(struct inode *inode);
462 struct inode *ovl_inode_lowerdata(struct inode *inode);
463 struct inode *ovl_inode_real(struct inode *inode);
464 struct inode *ovl_inode_realdata(struct inode *inode);
465 const char *ovl_lowerdata_redirect(struct inode *inode);
466 struct ovl_dir_cache *ovl_dir_cache(struct inode *inode);
467 void ovl_set_dir_cache(struct inode *inode, struct ovl_dir_cache *cache);
468 void ovl_dentry_set_flag(unsigned long flag, struct dentry *dentry);
469 void ovl_dentry_clear_flag(unsigned long flag, struct dentry *dentry);
470 bool ovl_dentry_test_flag(unsigned long flag, struct dentry *dentry);
471 bool ovl_dentry_is_opaque(struct dentry *dentry);
472 bool ovl_dentry_is_whiteout(struct dentry *dentry);
473 void ovl_dentry_set_opaque(struct dentry *dentry);
474 bool ovl_dentry_has_upper_alias(struct dentry *dentry);
475 void ovl_dentry_set_upper_alias(struct dentry *dentry);
476 bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags);
477 bool ovl_dentry_needs_data_copy_up_locked(struct dentry *dentry, int flags);
478 bool ovl_has_upperdata(struct inode *inode);
479 void ovl_set_upperdata(struct inode *inode);
480 const char *ovl_dentry_get_redirect(struct dentry *dentry);
481 void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect);
482 void ovl_inode_update(struct inode *inode, struct dentry *upperdentry);
483 void ovl_dir_modified(struct dentry *dentry, bool impurity);
484 u64 ovl_inode_version_get(struct inode *inode);
485 bool ovl_is_whiteout(struct dentry *dentry);
486 bool ovl_path_is_whiteout(struct ovl_fs *ofs, const struct path *path);
487 struct file *ovl_path_open(const struct path *path, int flags);
488 int ovl_copy_up_start(struct dentry *dentry, int flags);
489 void ovl_copy_up_end(struct dentry *dentry);
490 bool ovl_already_copied_up(struct dentry *dentry, int flags);
491 bool ovl_path_check_dir_xattr(struct ovl_fs *ofs, const struct path *path,
493 bool ovl_path_check_origin_xattr(struct ovl_fs *ofs, const struct path *path);
494 bool ovl_path_check_xwhiteout_xattr(struct ovl_fs *ofs, const struct path *path);
495 bool ovl_path_check_xwhiteouts_xattr(struct ovl_fs *ofs, const struct path *path);
496 bool ovl_init_uuid_xattr(struct super_block *sb, struct ovl_fs *ofs,
497 const struct path *upperpath);
499 static inline bool ovl_upper_is_whiteout(struct ovl_fs *ofs,
500 struct dentry *upperdentry)
502 struct path upperpath = {
503 .dentry = upperdentry,
504 .mnt = ovl_upper_mnt(ofs),
506 return ovl_path_is_whiteout(ofs, &upperpath);
509 static inline bool ovl_check_origin_xattr(struct ovl_fs *ofs,
510 struct dentry *upperdentry)
512 struct path upperpath = {
513 .dentry = upperdentry,
514 .mnt = ovl_upper_mnt(ofs),
516 return ovl_path_check_origin_xattr(ofs, &upperpath);
519 int ovl_check_setxattr(struct ovl_fs *ofs, struct dentry *upperdentry,
520 enum ovl_xattr ox, const void *value, size_t size,
522 int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry);
523 bool ovl_inuse_trylock(struct dentry *dentry);
524 void ovl_inuse_unlock(struct dentry *dentry);
525 bool ovl_is_inuse(struct dentry *dentry);
526 bool ovl_need_index(struct dentry *dentry);
527 int ovl_nlink_start(struct dentry *dentry);
528 void ovl_nlink_end(struct dentry *dentry);
529 int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
530 int ovl_check_metacopy_xattr(struct ovl_fs *ofs, const struct path *path,
531 struct ovl_metacopy *data);
532 int ovl_set_metacopy_xattr(struct ovl_fs *ofs, struct dentry *d,
533 struct ovl_metacopy *metacopy);
534 bool ovl_is_metacopy_dentry(struct dentry *dentry);
535 char *ovl_get_redirect_xattr(struct ovl_fs *ofs, const struct path *path, int padding);
536 int ovl_ensure_verity_loaded(struct path *path);
537 int ovl_get_verity_xattr(struct ovl_fs *ofs, const struct path *path,
538 u8 *digest_buf, int *buf_length);
539 int ovl_validate_verity(struct ovl_fs *ofs,
540 struct path *metapath,
541 struct path *datapath);
542 int ovl_get_verity_digest(struct ovl_fs *ofs, struct path *src,
543 struct ovl_metacopy *metacopy);
544 int ovl_sync_status(struct ovl_fs *ofs);
546 static inline void ovl_set_flag(unsigned long flag, struct inode *inode)
548 set_bit(flag, &OVL_I(inode)->flags);
551 static inline void ovl_clear_flag(unsigned long flag, struct inode *inode)
553 clear_bit(flag, &OVL_I(inode)->flags);
556 static inline bool ovl_test_flag(unsigned long flag, struct inode *inode)
558 return test_bit(flag, &OVL_I(inode)->flags);
561 static inline bool ovl_is_impuredir(struct super_block *sb,
562 struct dentry *upperdentry)
564 struct ovl_fs *ofs = OVL_FS(sb);
565 struct path upperpath = {
566 .dentry = upperdentry,
567 .mnt = ovl_upper_mnt(ofs),
570 return ovl_path_check_dir_xattr(ofs, &upperpath, OVL_XATTR_IMPURE);
573 static inline bool ovl_redirect_follow(struct ovl_fs *ofs)
575 return ofs->config.redirect_mode != OVL_REDIRECT_NOFOLLOW;
578 static inline bool ovl_redirect_dir(struct ovl_fs *ofs)
580 return ofs->config.redirect_mode == OVL_REDIRECT_ON;
583 static inline bool ovl_origin_uuid(struct ovl_fs *ofs)
585 return ofs->config.uuid != OVL_UUID_OFF;
588 static inline bool ovl_has_fsid(struct ovl_fs *ofs)
590 return ofs->config.uuid == OVL_UUID_ON ||
591 ofs->config.uuid == OVL_UUID_AUTO;
595 * With xino=auto, we do best effort to keep all inodes on same st_dev and
596 * d_ino consistent with st_ino.
597 * With xino=on, we do the same effort but we warn if we failed.
599 static inline bool ovl_xino_warn(struct ovl_fs *ofs)
601 return ofs->config.xino == OVL_XINO_ON;
605 * To avoid regressions in existing setups with overlay lower offline changes,
606 * we allow lower changes only if none of the new features are used.
608 static inline bool ovl_allow_offline_changes(struct ovl_fs *ofs)
610 return (!ofs->config.index && !ofs->config.metacopy &&
611 !ovl_redirect_dir(ofs) && !ovl_xino_warn(ofs));
614 /* All layers on same fs? */
615 static inline bool ovl_same_fs(struct ovl_fs *ofs)
617 return ofs->xino_mode == 0;
620 /* All overlay inodes have same st_dev? */
621 static inline bool ovl_same_dev(struct ovl_fs *ofs)
623 return ofs->xino_mode >= 0;
626 static inline unsigned int ovl_xino_bits(struct ovl_fs *ofs)
628 return ovl_same_dev(ofs) ? ofs->xino_mode : 0;
631 static inline void ovl_inode_lock(struct inode *inode)
633 mutex_lock(&OVL_I(inode)->lock);
636 static inline int ovl_inode_lock_interruptible(struct inode *inode)
638 return mutex_lock_interruptible(&OVL_I(inode)->lock);
641 static inline void ovl_inode_unlock(struct inode *inode)
643 mutex_unlock(&OVL_I(inode)->lock);
648 int ovl_check_fb_len(struct ovl_fb *fb, int fb_len);
650 static inline int ovl_check_fh_len(struct ovl_fh *fh, int fh_len)
652 if (fh_len < sizeof(struct ovl_fh))
655 return ovl_check_fb_len(&fh->fb, fh_len - OVL_FH_WIRE_OFFSET);
658 struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh,
659 struct vfsmount *mnt, bool connected);
660 int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
661 struct dentry *upperdentry, struct ovl_path **stackp);
662 int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
663 enum ovl_xattr ox, const struct ovl_fh *fh,
664 bool is_upper, bool set);
665 int ovl_verify_origin_xattr(struct ovl_fs *ofs, struct dentry *dentry,
666 enum ovl_xattr ox, struct dentry *real,
667 bool is_upper, bool set);
668 struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index,
670 int ovl_verify_index(struct ovl_fs *ofs, struct dentry *index);
671 int ovl_get_index_name_fh(const struct ovl_fh *fh, struct qstr *name);
672 int ovl_get_index_name(struct ovl_fs *ofs, struct dentry *origin,
674 struct dentry *ovl_get_index_fh(struct ovl_fs *ofs, struct ovl_fh *fh);
675 struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper,
676 struct dentry *origin, bool verify);
677 int ovl_path_next(int idx, struct dentry *dentry, struct path *path);
678 int ovl_verify_lowerdata(struct dentry *dentry);
679 struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
681 bool ovl_lower_positive(struct dentry *dentry);
683 static inline int ovl_verify_origin_fh(struct ovl_fs *ofs, struct dentry *upper,
684 const struct ovl_fh *fh, bool set)
686 return ovl_verify_set_fh(ofs, upper, OVL_XATTR_ORIGIN, fh, false, set);
689 static inline int ovl_verify_origin(struct ovl_fs *ofs, struct dentry *upper,
690 struct dentry *origin, bool set)
692 return ovl_verify_origin_xattr(ofs, upper, OVL_XATTR_ORIGIN, origin,
696 static inline int ovl_verify_upper(struct ovl_fs *ofs, struct dentry *index,
697 struct dentry *upper, bool set)
699 return ovl_verify_origin_xattr(ofs, index, OVL_XATTR_UPPER, upper,
704 extern const struct file_operations ovl_dir_operations;
705 struct file *ovl_dir_real_file(const struct file *file, bool want_upper);
706 int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list);
707 void ovl_cleanup_whiteouts(struct ovl_fs *ofs, struct dentry *upper,
708 struct list_head *list);
709 void ovl_cache_free(struct list_head *list);
710 void ovl_dir_cache_free(struct inode *inode);
711 int ovl_check_d_type_supported(const struct path *realpath);
712 int ovl_workdir_cleanup(struct ovl_fs *ofs, struct inode *dir,
713 struct vfsmount *mnt, struct dentry *dentry, int level);
714 int ovl_indexdir_cleanup(struct ovl_fs *ofs);
717 * Can we iterate real dir directly?
719 * Non-merge dir may contain whiteouts from a time it was a merge upper, before
720 * lower dir was removed under it and possibly before it was rotated from upper
723 static inline bool ovl_dir_is_real(struct inode *dir)
725 return !ovl_test_flag(OVL_WHITEOUTS, dir);
729 int ovl_set_nlink_upper(struct dentry *dentry);
730 int ovl_set_nlink_lower(struct dentry *dentry);
731 unsigned int ovl_get_nlink(struct ovl_fs *ofs, struct dentry *lowerdentry,
732 struct dentry *upperdentry,
733 unsigned int fallback);
734 int ovl_permission(struct mnt_idmap *idmap, struct inode *inode,
737 #ifdef CONFIG_FS_POSIX_ACL
738 struct posix_acl *do_ovl_get_acl(struct mnt_idmap *idmap,
739 struct inode *inode, int type,
740 bool rcu, bool noperm);
741 static inline struct posix_acl *ovl_get_inode_acl(struct inode *inode, int type,
744 return do_ovl_get_acl(&nop_mnt_idmap, inode, type, rcu, true);
746 static inline struct posix_acl *ovl_get_acl(struct mnt_idmap *idmap,
747 struct dentry *dentry, int type)
749 return do_ovl_get_acl(idmap, d_inode(dentry), type, false, false);
751 int ovl_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
752 struct posix_acl *acl, int type);
753 struct posix_acl *ovl_get_acl_path(const struct path *path,
754 const char *acl_name, bool noperm);
756 #define ovl_get_inode_acl NULL
757 #define ovl_get_acl NULL
758 #define ovl_set_acl NULL
759 static inline struct posix_acl *ovl_get_acl_path(const struct path *path,
760 const char *acl_name,
767 int ovl_update_time(struct inode *inode, int flags);
768 bool ovl_is_private_xattr(struct super_block *sb, const char *name);
770 struct ovl_inode_params {
771 struct inode *newinode;
772 struct dentry *upperdentry;
773 struct ovl_entry *oe;
776 char *lowerdata_redirect;
778 void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
779 unsigned long ino, int fsid);
780 struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev);
781 struct inode *ovl_lookup_inode(struct super_block *sb, struct dentry *real,
783 bool ovl_lookup_trap_inode(struct super_block *sb, struct dentry *dir);
784 struct inode *ovl_get_trap_inode(struct super_block *sb, struct dentry *dir);
785 struct inode *ovl_get_inode(struct super_block *sb,
786 struct ovl_inode_params *oip);
787 void ovl_copyattr(struct inode *to);
789 /* vfs inode flags copied from real to ovl inode */
790 #define OVL_COPY_I_FLAGS_MASK (S_SYNC | S_NOATIME | S_APPEND | S_IMMUTABLE)
791 /* vfs inode flags read from overlay.protattr xattr to ovl inode */
792 #define OVL_PROT_I_FLAGS_MASK (S_APPEND | S_IMMUTABLE)
795 * fileattr flags copied from lower to upper inode on copy up.
796 * We cannot copy up immutable/append-only flags, because that would prevent
797 * linking temp inode to upper dir, so we store them in xattr instead.
799 #define OVL_COPY_FS_FLAGS_MASK (FS_SYNC_FL | FS_NOATIME_FL)
800 #define OVL_COPY_FSX_FLAGS_MASK (FS_XFLAG_SYNC | FS_XFLAG_NOATIME)
801 #define OVL_PROT_FS_FLAGS_MASK (FS_APPEND_FL | FS_IMMUTABLE_FL)
802 #define OVL_PROT_FSX_FLAGS_MASK (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE)
804 void ovl_check_protattr(struct inode *inode, struct dentry *upper);
805 int ovl_set_protattr(struct inode *inode, struct dentry *upper,
806 struct fileattr *fa);
808 static inline void ovl_copyflags(struct inode *from, struct inode *to)
810 unsigned int mask = OVL_COPY_I_FLAGS_MASK;
812 inode_set_flags(to, from->i_flags & mask, mask);
816 extern const struct inode_operations ovl_dir_inode_operations;
817 int ovl_cleanup_and_whiteout(struct ovl_fs *ofs, struct inode *dir,
818 struct dentry *dentry);
823 struct dentry *hardlink;
826 #define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
828 int ovl_mkdir_real(struct ovl_fs *ofs, struct inode *dir,
829 struct dentry **newdentry, umode_t mode);
830 struct dentry *ovl_create_real(struct ovl_fs *ofs,
831 struct inode *dir, struct dentry *newdentry,
832 struct ovl_cattr *attr);
833 int ovl_cleanup(struct ovl_fs *ofs, struct inode *dir, struct dentry *dentry);
834 struct dentry *ovl_lookup_temp(struct ovl_fs *ofs, struct dentry *workdir);
835 struct dentry *ovl_create_temp(struct ovl_fs *ofs, struct dentry *workdir,
836 struct ovl_cattr *attr);
839 extern const struct file_operations ovl_file_operations;
840 int __init ovl_aio_request_cache_init(void);
841 void ovl_aio_request_cache_destroy(void);
842 int ovl_real_fileattr_get(const struct path *realpath, struct fileattr *fa);
843 int ovl_real_fileattr_set(const struct path *realpath, struct fileattr *fa);
844 int ovl_fileattr_get(struct dentry *dentry, struct fileattr *fa);
845 int ovl_fileattr_set(struct mnt_idmap *idmap,
846 struct dentry *dentry, struct fileattr *fa);
849 int ovl_copy_up(struct dentry *dentry);
850 int ovl_copy_up_with_data(struct dentry *dentry);
851 int ovl_maybe_copy_up(struct dentry *dentry, int flags);
852 int ovl_copy_xattr(struct super_block *sb, const struct path *path, struct dentry *new);
853 int ovl_set_attr(struct ovl_fs *ofs, struct dentry *upper, struct kstat *stat);
854 struct ovl_fh *ovl_encode_real_fh(struct ovl_fs *ofs, struct dentry *real,
856 struct ovl_fh *ovl_get_origin_fh(struct ovl_fs *ofs, struct dentry *origin);
857 int ovl_set_origin_fh(struct ovl_fs *ofs, const struct ovl_fh *fh,
858 struct dentry *upper);
861 extern const struct export_operations ovl_export_operations;
862 extern const struct export_operations ovl_export_fid_operations;
865 int ovl_fill_super(struct super_block *sb, struct fs_context *fc);
867 /* Will this overlay be forced to mount/remount ro? */
868 static inline bool ovl_force_readonly(struct ovl_fs *ofs)
870 return (!ovl_upper_mnt(ofs) || !ofs->workdir);
875 const struct xattr_handler * const *ovl_xattr_handlers(struct ovl_fs *ofs);
876 int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
878 int ovl_getattr(struct mnt_idmap *idmap, const struct path *path,
879 struct kstat *stat, u32 request_mask, unsigned int flags);
880 ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);