3 * Copyright (C) 2011 Novell Inc.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
10 #include <linux/kernel.h>
11 #include <linux/uuid.h>
12 #include "ovl_entry.h"
15 __OVL_PATH_UPPER
= (1 << 0),
16 __OVL_PATH_MERGE
= (1 << 1),
17 __OVL_PATH_ORIGIN
= (1 << 2),
20 #define OVL_TYPE_UPPER(type) ((type) & __OVL_PATH_UPPER)
21 #define OVL_TYPE_MERGE(type) ((type) & __OVL_PATH_MERGE)
22 #define OVL_TYPE_ORIGIN(type) ((type) & __OVL_PATH_ORIGIN)
24 #define OVL_XATTR_PREFIX XATTR_TRUSTED_PREFIX "overlay."
25 #define OVL_XATTR_OPAQUE OVL_XATTR_PREFIX "opaque"
26 #define OVL_XATTR_REDIRECT OVL_XATTR_PREFIX "redirect"
27 #define OVL_XATTR_ORIGIN OVL_XATTR_PREFIX "origin"
28 #define OVL_XATTR_IMPURE OVL_XATTR_PREFIX "impure"
29 #define OVL_XATTR_NLINK OVL_XATTR_PREFIX "nlink"
30 #define OVL_XATTR_UPPER OVL_XATTR_PREFIX "upper"
33 /* Pure upper dir that may contain non pure upper entries */
35 /* Non-merge dir that may contain whiteout entries */
47 * The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
49 * origin.fh - exported file handle of the lower file
50 * origin.uuid - uuid of the lower filesystem
52 #define OVL_FH_VERSION 0
53 #define OVL_FH_MAGIC 0xfb
55 /* CPU byte order required for fid decoding: */
56 #define OVL_FH_FLAG_BIG_ENDIAN (1 << 0)
57 #define OVL_FH_FLAG_ANY_ENDIAN (1 << 1)
58 /* Is the real inode encoded in fid an upper inode? */
59 #define OVL_FH_FLAG_PATH_UPPER (1 << 2)
61 #define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN | \
62 OVL_FH_FLAG_PATH_UPPER)
64 #if defined(__LITTLE_ENDIAN)
65 #define OVL_FH_FLAG_CPU_ENDIAN 0
66 #elif defined(__BIG_ENDIAN)
67 #define OVL_FH_FLAG_CPU_ENDIAN OVL_FH_FLAG_BIG_ENDIAN
69 #error Endianness not defined
72 /* The type returned by overlay exportfs ops when encoding an ovl_fh handle */
73 #define OVL_FILEID 0xfb
75 /* On-disk and in-memeory format for redirect by file handle */
79 u8 len
; /* size of this header + size of fid */
80 u8 flags
; /* OVL_FH_FLAG_* */
81 u8 type
; /* fid_type of fid */
82 uuid_t uuid
; /* uuid of filesystem */
83 u8 fid
[0]; /* file identifier */
86 static inline int ovl_do_rmdir(struct inode
*dir
, struct dentry
*dentry
)
88 int err
= vfs_rmdir(dir
, dentry
);
90 pr_debug("rmdir(%pd2) = %i\n", dentry
, err
);
94 static inline int ovl_do_unlink(struct inode
*dir
, struct dentry
*dentry
)
96 int err
= vfs_unlink(dir
, dentry
, NULL
);
98 pr_debug("unlink(%pd2) = %i\n", dentry
, err
);
102 static inline int ovl_do_link(struct dentry
*old_dentry
, struct inode
*dir
,
103 struct dentry
*new_dentry
)
105 int err
= vfs_link(old_dentry
, dir
, new_dentry
, NULL
);
107 pr_debug("link(%pd2, %pd2) = %i\n", old_dentry
, new_dentry
, err
);
111 static inline int ovl_do_create(struct inode
*dir
, struct dentry
*dentry
,
114 int err
= vfs_create(dir
, dentry
, mode
, true);
116 pr_debug("create(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
120 static inline int ovl_do_mkdir(struct inode
*dir
, struct dentry
*dentry
,
123 int err
= vfs_mkdir(dir
, dentry
, mode
);
124 pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
128 static inline int ovl_do_mknod(struct inode
*dir
, struct dentry
*dentry
,
129 umode_t mode
, dev_t dev
)
131 int err
= vfs_mknod(dir
, dentry
, mode
, dev
);
133 pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry
, mode
, dev
, err
);
137 static inline int ovl_do_symlink(struct inode
*dir
, struct dentry
*dentry
,
140 int err
= vfs_symlink(dir
, dentry
, oldname
);
142 pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname
, dentry
, err
);
146 static inline int ovl_do_setxattr(struct dentry
*dentry
, const char *name
,
147 const void *value
, size_t size
, int flags
)
149 int err
= vfs_setxattr(dentry
, name
, value
, size
, flags
);
150 pr_debug("setxattr(%pd2, \"%s\", \"%*s\", 0x%x) = %i\n",
151 dentry
, name
, (int) size
, (char *) value
, flags
, err
);
155 static inline int ovl_do_removexattr(struct dentry
*dentry
, const char *name
)
157 int err
= vfs_removexattr(dentry
, name
);
158 pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry
, name
, err
);
162 static inline int ovl_do_rename(struct inode
*olddir
, struct dentry
*olddentry
,
163 struct inode
*newdir
, struct dentry
*newdentry
,
168 pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry
, newdentry
, flags
);
169 err
= vfs_rename(olddir
, olddentry
, newdir
, newdentry
, NULL
, flags
);
171 pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
172 olddentry
, newdentry
, err
);
177 static inline int ovl_do_whiteout(struct inode
*dir
, struct dentry
*dentry
)
179 int err
= vfs_whiteout(dir
, dentry
);
180 pr_debug("whiteout(%pd2) = %i\n", dentry
, err
);
184 static inline struct dentry
*ovl_do_tmpfile(struct dentry
*dentry
, umode_t mode
)
186 struct dentry
*ret
= vfs_tmpfile(dentry
, mode
, 0);
187 int err
= PTR_ERR_OR_ZERO(ret
);
189 pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
194 int ovl_want_write(struct dentry
*dentry
);
195 void ovl_drop_write(struct dentry
*dentry
);
196 struct dentry
*ovl_workdir(struct dentry
*dentry
);
197 const struct cred
*ovl_override_creds(struct super_block
*sb
);
198 struct super_block
*ovl_same_sb(struct super_block
*sb
);
199 int ovl_can_decode_fh(struct super_block
*sb
);
200 struct dentry
*ovl_indexdir(struct super_block
*sb
);
201 bool ovl_index_all(struct super_block
*sb
);
202 bool ovl_verify_lower(struct super_block
*sb
);
203 struct ovl_entry
*ovl_alloc_entry(unsigned int numlower
);
204 bool ovl_dentry_remote(struct dentry
*dentry
);
205 bool ovl_dentry_weird(struct dentry
*dentry
);
206 enum ovl_path_type
ovl_path_type(struct dentry
*dentry
);
207 void ovl_path_upper(struct dentry
*dentry
, struct path
*path
);
208 void ovl_path_lower(struct dentry
*dentry
, struct path
*path
);
209 enum ovl_path_type
ovl_path_real(struct dentry
*dentry
, struct path
*path
);
210 struct dentry
*ovl_dentry_upper(struct dentry
*dentry
);
211 struct dentry
*ovl_dentry_lower(struct dentry
*dentry
);
212 struct ovl_layer
*ovl_layer_lower(struct dentry
*dentry
);
213 struct dentry
*ovl_dentry_real(struct dentry
*dentry
);
214 struct dentry
*ovl_i_dentry_upper(struct inode
*inode
);
215 struct inode
*ovl_inode_upper(struct inode
*inode
);
216 struct inode
*ovl_inode_lower(struct inode
*inode
);
217 struct inode
*ovl_inode_real(struct inode
*inode
);
218 struct ovl_dir_cache
*ovl_dir_cache(struct inode
*inode
);
219 void ovl_set_dir_cache(struct inode
*inode
, struct ovl_dir_cache
*cache
);
220 void ovl_dentry_set_flag(unsigned long flag
, struct dentry
*dentry
);
221 void ovl_dentry_clear_flag(unsigned long flag
, struct dentry
*dentry
);
222 bool ovl_dentry_test_flag(unsigned long flag
, struct dentry
*dentry
);
223 bool ovl_dentry_is_opaque(struct dentry
*dentry
);
224 bool ovl_dentry_is_whiteout(struct dentry
*dentry
);
225 void ovl_dentry_set_opaque(struct dentry
*dentry
);
226 bool ovl_dentry_has_upper_alias(struct dentry
*dentry
);
227 void ovl_dentry_set_upper_alias(struct dentry
*dentry
);
228 bool ovl_redirect_dir(struct super_block
*sb
);
229 const char *ovl_dentry_get_redirect(struct dentry
*dentry
);
230 void ovl_dentry_set_redirect(struct dentry
*dentry
, const char *redirect
);
231 void ovl_inode_init(struct inode
*inode
, struct dentry
*upperdentry
,
232 struct dentry
*lowerdentry
);
233 void ovl_inode_update(struct inode
*inode
, struct dentry
*upperdentry
);
234 void ovl_dir_modified(struct dentry
*dentry
, bool impurity
);
235 u64
ovl_dentry_version_get(struct dentry
*dentry
);
236 bool ovl_is_whiteout(struct dentry
*dentry
);
237 struct file
*ovl_path_open(struct path
*path
, int flags
);
238 int ovl_copy_up_start(struct dentry
*dentry
);
239 void ovl_copy_up_end(struct dentry
*dentry
);
240 bool ovl_check_origin_xattr(struct dentry
*dentry
);
241 bool ovl_check_dir_xattr(struct dentry
*dentry
, const char *name
);
242 int ovl_check_setxattr(struct dentry
*dentry
, struct dentry
*upperdentry
,
243 const char *name
, const void *value
, size_t size
,
245 int ovl_set_impure(struct dentry
*dentry
, struct dentry
*upperdentry
);
246 void ovl_set_flag(unsigned long flag
, struct inode
*inode
);
247 void ovl_clear_flag(unsigned long flag
, struct inode
*inode
);
248 bool ovl_test_flag(unsigned long flag
, struct inode
*inode
);
249 bool ovl_inuse_trylock(struct dentry
*dentry
);
250 void ovl_inuse_unlock(struct dentry
*dentry
);
251 bool ovl_need_index(struct dentry
*dentry
);
252 int ovl_nlink_start(struct dentry
*dentry
, bool *locked
);
253 void ovl_nlink_end(struct dentry
*dentry
, bool locked
);
254 int ovl_lock_rename_workdir(struct dentry
*workdir
, struct dentry
*upperdir
);
256 static inline bool ovl_is_impuredir(struct dentry
*dentry
)
258 return ovl_check_dir_xattr(dentry
, OVL_XATTR_IMPURE
);
261 static inline unsigned int ovl_xino_bits(struct super_block
*sb
)
263 struct ovl_fs
*ofs
= sb
->s_fs_info
;
265 return ofs
->xino_bits
;
270 int ovl_check_fh_len(struct ovl_fh
*fh
, int fh_len
);
271 struct dentry
*ovl_decode_real_fh(struct ovl_fh
*fh
, struct vfsmount
*mnt
,
273 int ovl_check_origin_fh(struct ovl_fs
*ofs
, struct ovl_fh
*fh
, bool connected
,
274 struct dentry
*upperdentry
, struct ovl_path
**stackp
);
275 int ovl_verify_set_fh(struct dentry
*dentry
, const char *name
,
276 struct dentry
*real
, bool is_upper
, bool set
);
277 struct dentry
*ovl_index_upper(struct ovl_fs
*ofs
, struct dentry
*index
);
278 int ovl_verify_index(struct ovl_fs
*ofs
, struct dentry
*index
);
279 int ovl_get_index_name(struct dentry
*origin
, struct qstr
*name
);
280 struct dentry
*ovl_get_index_fh(struct ovl_fs
*ofs
, struct ovl_fh
*fh
);
281 struct dentry
*ovl_lookup_index(struct ovl_fs
*ofs
, struct dentry
*upper
,
282 struct dentry
*origin
, bool verify
);
283 int ovl_path_next(int idx
, struct dentry
*dentry
, struct path
*path
);
284 struct dentry
*ovl_lookup(struct inode
*dir
, struct dentry
*dentry
,
286 bool ovl_lower_positive(struct dentry
*dentry
);
288 static inline int ovl_verify_origin(struct dentry
*upper
,
289 struct dentry
*origin
, bool set
)
291 return ovl_verify_set_fh(upper
, OVL_XATTR_ORIGIN
, origin
, false, set
);
294 static inline int ovl_verify_upper(struct dentry
*index
,
295 struct dentry
*upper
, bool set
)
297 return ovl_verify_set_fh(index
, OVL_XATTR_UPPER
, upper
, true, set
);
301 extern const struct file_operations ovl_dir_operations
;
302 int ovl_check_empty_dir(struct dentry
*dentry
, struct list_head
*list
);
303 void ovl_cleanup_whiteouts(struct dentry
*upper
, struct list_head
*list
);
304 void ovl_cache_free(struct list_head
*list
);
305 void ovl_dir_cache_free(struct inode
*inode
);
306 int ovl_check_d_type_supported(struct path
*realpath
);
307 void ovl_workdir_cleanup(struct inode
*dir
, struct vfsmount
*mnt
,
308 struct dentry
*dentry
, int level
);
309 int ovl_indexdir_cleanup(struct ovl_fs
*ofs
);
312 int ovl_set_nlink_upper(struct dentry
*dentry
);
313 int ovl_set_nlink_lower(struct dentry
*dentry
);
314 unsigned int ovl_get_nlink(struct dentry
*lowerdentry
,
315 struct dentry
*upperdentry
,
316 unsigned int fallback
);
317 int ovl_setattr(struct dentry
*dentry
, struct iattr
*attr
);
318 int ovl_getattr(const struct path
*path
, struct kstat
*stat
,
319 u32 request_mask
, unsigned int flags
);
320 int ovl_permission(struct inode
*inode
, int mask
);
321 int ovl_xattr_set(struct dentry
*dentry
, struct inode
*inode
, const char *name
,
322 const void *value
, size_t size
, int flags
);
323 int ovl_xattr_get(struct dentry
*dentry
, struct inode
*inode
, const char *name
,
324 void *value
, size_t size
);
325 ssize_t
ovl_listxattr(struct dentry
*dentry
, char *list
, size_t size
);
326 struct posix_acl
*ovl_get_acl(struct inode
*inode
, int type
);
327 int ovl_open_maybe_copy_up(struct dentry
*dentry
, unsigned int file_flags
);
328 int ovl_update_time(struct inode
*inode
, struct timespec64
*ts
, int flags
);
329 bool ovl_is_private_xattr(const char *name
);
331 struct ovl_inode_params
{
332 struct inode
*newinode
;
333 struct dentry
*upperdentry
;
334 struct ovl_path
*lowerpath
;
335 struct dentry
*index
;
336 unsigned int numlower
;
338 struct inode
*ovl_new_inode(struct super_block
*sb
, umode_t mode
, dev_t rdev
);
339 struct inode
*ovl_lookup_inode(struct super_block
*sb
, struct dentry
*real
,
341 struct inode
*ovl_get_inode(struct super_block
*sb
,
342 struct ovl_inode_params
*oip
);
343 static inline void ovl_copyattr(struct inode
*from
, struct inode
*to
)
345 to
->i_uid
= from
->i_uid
;
346 to
->i_gid
= from
->i_gid
;
347 to
->i_mode
= from
->i_mode
;
348 to
->i_atime
= from
->i_atime
;
349 to
->i_mtime
= from
->i_mtime
;
350 to
->i_ctime
= from
->i_ctime
;
353 static inline void ovl_copyflags(struct inode
*from
, struct inode
*to
)
355 unsigned int mask
= S_SYNC
| S_IMMUTABLE
| S_APPEND
| S_NOATIME
;
357 inode_set_flags(to
, from
->i_flags
& mask
, mask
);
361 extern const struct inode_operations ovl_dir_inode_operations
;
362 int ovl_cleanup_and_whiteout(struct dentry
*workdir
, struct inode
*dir
,
363 struct dentry
*dentry
);
368 struct dentry
*hardlink
;
371 #define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
373 struct dentry
*ovl_create_real(struct inode
*dir
, struct dentry
*newdentry
,
374 struct ovl_cattr
*attr
);
375 int ovl_cleanup(struct inode
*dir
, struct dentry
*dentry
);
376 struct dentry
*ovl_create_temp(struct dentry
*workdir
, struct ovl_cattr
*attr
);
379 int ovl_copy_up(struct dentry
*dentry
);
380 int ovl_copy_up_flags(struct dentry
*dentry
, int flags
);
381 int ovl_copy_xattr(struct dentry
*old
, struct dentry
*new);
382 int ovl_set_attr(struct dentry
*upper
, struct kstat
*stat
);
383 struct ovl_fh
*ovl_encode_real_fh(struct dentry
*real
, bool is_upper
);
384 int ovl_set_origin(struct dentry
*dentry
, struct dentry
*lower
,
385 struct dentry
*upper
);
388 extern const struct export_operations ovl_export_operations
;