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>
14 __OVL_PATH_UPPER
= (1 << 0),
15 __OVL_PATH_MERGE
= (1 << 1),
16 __OVL_PATH_ORIGIN
= (1 << 2),
19 #define OVL_TYPE_UPPER(type) ((type) & __OVL_PATH_UPPER)
20 #define OVL_TYPE_MERGE(type) ((type) & __OVL_PATH_MERGE)
21 #define OVL_TYPE_ORIGIN(type) ((type) & __OVL_PATH_ORIGIN)
23 #define OVL_XATTR_PREFIX XATTR_TRUSTED_PREFIX "overlay."
24 #define OVL_XATTR_OPAQUE OVL_XATTR_PREFIX "opaque"
25 #define OVL_XATTR_REDIRECT OVL_XATTR_PREFIX "redirect"
26 #define OVL_XATTR_ORIGIN OVL_XATTR_PREFIX "origin"
27 #define OVL_XATTR_IMPURE OVL_XATTR_PREFIX "impure"
30 * The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
32 * origin.fh - exported file handle of the lower file
33 * origin.uuid - uuid of the lower filesystem
35 #define OVL_FH_VERSION 0
36 #define OVL_FH_MAGIC 0xfb
38 /* CPU byte order required for fid decoding: */
39 #define OVL_FH_FLAG_BIG_ENDIAN (1 << 0)
40 #define OVL_FH_FLAG_ANY_ENDIAN (1 << 1)
42 #define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN)
44 #if defined(__LITTLE_ENDIAN)
45 #define OVL_FH_FLAG_CPU_ENDIAN 0
46 #elif defined(__BIG_ENDIAN)
47 #define OVL_FH_FLAG_CPU_ENDIAN OVL_FH_FLAG_BIG_ENDIAN
49 #error Endianness not defined
52 /* On-disk and in-memeory format for redirect by file handle */
56 u8 len
; /* size of this header + size of fid */
57 u8 flags
; /* OVL_FH_FLAG_* */
58 u8 type
; /* fid_type of fid */
59 uuid_be uuid
; /* uuid of filesystem */
60 u8 fid
[0]; /* file identifier */
63 #define OVL_ISUPPER_MASK 1UL
65 static inline int ovl_do_rmdir(struct inode
*dir
, struct dentry
*dentry
)
67 int err
= vfs_rmdir(dir
, dentry
);
68 pr_debug("rmdir(%pd2) = %i\n", dentry
, err
);
72 static inline int ovl_do_unlink(struct inode
*dir
, struct dentry
*dentry
)
74 int err
= vfs_unlink(dir
, dentry
, NULL
);
75 pr_debug("unlink(%pd2) = %i\n", dentry
, err
);
79 static inline int ovl_do_link(struct dentry
*old_dentry
, struct inode
*dir
,
80 struct dentry
*new_dentry
, bool debug
)
82 int err
= vfs_link(old_dentry
, dir
, new_dentry
, NULL
);
84 pr_debug("link(%pd2, %pd2) = %i\n",
85 old_dentry
, new_dentry
, err
);
90 static inline int ovl_do_create(struct inode
*dir
, struct dentry
*dentry
,
91 umode_t mode
, bool debug
)
93 int err
= vfs_create(dir
, dentry
, mode
, true);
95 pr_debug("create(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
99 static inline int ovl_do_mkdir(struct inode
*dir
, struct dentry
*dentry
,
100 umode_t mode
, bool debug
)
102 int err
= vfs_mkdir(dir
, dentry
, mode
);
104 pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
108 static inline int ovl_do_mknod(struct inode
*dir
, struct dentry
*dentry
,
109 umode_t mode
, dev_t dev
, bool debug
)
111 int err
= vfs_mknod(dir
, dentry
, mode
, dev
);
113 pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n",
114 dentry
, mode
, dev
, err
);
119 static inline int ovl_do_symlink(struct inode
*dir
, struct dentry
*dentry
,
120 const char *oldname
, bool debug
)
122 int err
= vfs_symlink(dir
, dentry
, oldname
);
124 pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname
, dentry
, err
);
128 static inline int ovl_do_setxattr(struct dentry
*dentry
, const char *name
,
129 const void *value
, size_t size
, int flags
)
131 int err
= vfs_setxattr(dentry
, name
, value
, size
, flags
);
132 pr_debug("setxattr(%pd2, \"%s\", \"%*s\", 0x%x) = %i\n",
133 dentry
, name
, (int) size
, (char *) value
, flags
, err
);
137 static inline int ovl_do_removexattr(struct dentry
*dentry
, const char *name
)
139 int err
= vfs_removexattr(dentry
, name
);
140 pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry
, name
, err
);
144 static inline int ovl_do_rename(struct inode
*olddir
, struct dentry
*olddentry
,
145 struct inode
*newdir
, struct dentry
*newdentry
,
150 pr_debug("rename(%pd2, %pd2, 0x%x)\n",
151 olddentry
, newdentry
, flags
);
153 err
= vfs_rename(olddir
, olddentry
, newdir
, newdentry
, NULL
, flags
);
156 pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
157 olddentry
, newdentry
, err
);
162 static inline int ovl_do_whiteout(struct inode
*dir
, struct dentry
*dentry
)
164 int err
= vfs_whiteout(dir
, dentry
);
165 pr_debug("whiteout(%pd2) = %i\n", dentry
, err
);
169 static inline struct dentry
*ovl_do_tmpfile(struct dentry
*dentry
, umode_t mode
)
171 struct dentry
*ret
= vfs_tmpfile(dentry
, mode
, 0);
172 int err
= IS_ERR(ret
) ? PTR_ERR(ret
) : 0;
174 pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry
, mode
, err
);
178 static inline struct inode
*ovl_inode_real(struct inode
*inode
, bool *is_upper
)
180 unsigned long x
= (unsigned long) READ_ONCE(inode
->i_private
);
183 *is_upper
= x
& OVL_ISUPPER_MASK
;
185 return (struct inode
*) (x
& ~OVL_ISUPPER_MASK
);
189 int ovl_want_write(struct dentry
*dentry
);
190 void ovl_drop_write(struct dentry
*dentry
);
191 struct dentry
*ovl_workdir(struct dentry
*dentry
);
192 const struct cred
*ovl_override_creds(struct super_block
*sb
);
193 struct super_block
*ovl_same_sb(struct super_block
*sb
);
194 struct ovl_entry
*ovl_alloc_entry(unsigned int numlower
);
195 bool ovl_dentry_remote(struct dentry
*dentry
);
196 bool ovl_dentry_weird(struct dentry
*dentry
);
197 enum ovl_path_type
ovl_path_type(struct dentry
*dentry
);
198 void ovl_path_upper(struct dentry
*dentry
, struct path
*path
);
199 void ovl_path_lower(struct dentry
*dentry
, struct path
*path
);
200 enum ovl_path_type
ovl_path_real(struct dentry
*dentry
, struct path
*path
);
201 struct dentry
*ovl_dentry_upper(struct dentry
*dentry
);
202 struct dentry
*ovl_dentry_lower(struct dentry
*dentry
);
203 struct dentry
*ovl_dentry_real(struct dentry
*dentry
);
204 struct ovl_dir_cache
*ovl_dir_cache(struct dentry
*dentry
);
205 void ovl_set_dir_cache(struct dentry
*dentry
, struct ovl_dir_cache
*cache
);
206 bool ovl_dentry_is_opaque(struct dentry
*dentry
);
207 bool ovl_dentry_is_impure(struct dentry
*dentry
);
208 bool ovl_dentry_is_whiteout(struct dentry
*dentry
);
209 void ovl_dentry_set_opaque(struct dentry
*dentry
);
210 bool ovl_redirect_dir(struct super_block
*sb
);
211 const char *ovl_dentry_get_redirect(struct dentry
*dentry
);
212 void ovl_dentry_set_redirect(struct dentry
*dentry
, const char *redirect
);
213 void ovl_dentry_update(struct dentry
*dentry
, struct dentry
*upperdentry
);
214 void ovl_inode_init(struct inode
*inode
, struct inode
*realinode
,
216 void ovl_inode_update(struct inode
*inode
, struct inode
*upperinode
);
217 void ovl_dentry_version_inc(struct dentry
*dentry
);
218 u64
ovl_dentry_version_get(struct dentry
*dentry
);
219 bool ovl_is_whiteout(struct dentry
*dentry
);
220 struct file
*ovl_path_open(struct path
*path
, int flags
);
221 int ovl_copy_up_start(struct dentry
*dentry
);
222 void ovl_copy_up_end(struct dentry
*dentry
);
223 bool ovl_check_dir_xattr(struct dentry
*dentry
, const char *name
);
224 int ovl_check_setxattr(struct dentry
*dentry
, struct dentry
*upperdentry
,
225 const char *name
, const void *value
, size_t size
,
227 int ovl_set_impure(struct dentry
*dentry
, struct dentry
*upperdentry
);
229 static inline bool ovl_is_impuredir(struct dentry
*dentry
)
231 return ovl_check_dir_xattr(dentry
, OVL_XATTR_IMPURE
);
236 int ovl_path_next(int idx
, struct dentry
*dentry
, struct path
*path
);
237 struct dentry
*ovl_lookup(struct inode
*dir
, struct dentry
*dentry
, unsigned int flags
);
238 bool ovl_lower_positive(struct dentry
*dentry
);
241 extern const struct file_operations ovl_dir_operations
;
242 int ovl_check_empty_dir(struct dentry
*dentry
, struct list_head
*list
);
243 void ovl_cleanup_whiteouts(struct dentry
*upper
, struct list_head
*list
);
244 void ovl_cache_free(struct list_head
*list
);
245 int ovl_check_d_type_supported(struct path
*realpath
);
246 void ovl_workdir_cleanup(struct inode
*dir
, struct vfsmount
*mnt
,
247 struct dentry
*dentry
, int level
);
250 int ovl_setattr(struct dentry
*dentry
, struct iattr
*attr
);
251 int ovl_getattr(const struct path
*path
, struct kstat
*stat
,
252 u32 request_mask
, unsigned int flags
);
253 int ovl_permission(struct inode
*inode
, int mask
);
254 int ovl_xattr_set(struct dentry
*dentry
, const char *name
, const void *value
,
255 size_t size
, int flags
);
256 int ovl_xattr_get(struct dentry
*dentry
, const char *name
,
257 void *value
, size_t size
);
258 ssize_t
ovl_listxattr(struct dentry
*dentry
, char *list
, size_t size
);
259 struct posix_acl
*ovl_get_acl(struct inode
*inode
, int type
);
260 int ovl_open_maybe_copy_up(struct dentry
*dentry
, unsigned int file_flags
);
261 int ovl_update_time(struct inode
*inode
, struct timespec
*ts
, int flags
);
262 bool ovl_is_private_xattr(const char *name
);
264 struct inode
*ovl_new_inode(struct super_block
*sb
, umode_t mode
, dev_t rdev
);
265 struct inode
*ovl_get_inode(struct super_block
*sb
, struct inode
*realinode
);
266 static inline void ovl_copyattr(struct inode
*from
, struct inode
*to
)
268 to
->i_uid
= from
->i_uid
;
269 to
->i_gid
= from
->i_gid
;
270 to
->i_mode
= from
->i_mode
;
271 to
->i_atime
= from
->i_atime
;
272 to
->i_mtime
= from
->i_mtime
;
273 to
->i_ctime
= from
->i_ctime
;
277 extern const struct inode_operations ovl_dir_inode_operations
;
278 struct dentry
*ovl_lookup_temp(struct dentry
*workdir
);
284 int ovl_create_real(struct inode
*dir
, struct dentry
*newdentry
,
286 struct dentry
*hardlink
, bool debug
);
287 void ovl_cleanup(struct inode
*dir
, struct dentry
*dentry
);
290 int ovl_copy_up(struct dentry
*dentry
);
291 int ovl_copy_up_flags(struct dentry
*dentry
, int flags
);
292 int ovl_copy_xattr(struct dentry
*old
, struct dentry
*new);
293 int ovl_set_attr(struct dentry
*upper
, struct kstat
*stat
);