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