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git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - fs/stat.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
7 #include <linux/export.h>
9 #include <linux/errno.h>
10 #include <linux/file.h>
11 #include <linux/highuid.h>
13 #include <linux/namei.h>
14 #include <linux/security.h>
15 #include <linux/cred.h>
16 #include <linux/syscalls.h>
17 #include <linux/pagemap.h>
19 #include <linux/uaccess.h>
20 #include <asm/unistd.h>
22 void generic_fillattr(struct inode
*inode
, struct kstat
*stat
)
24 stat
->dev
= inode
->i_sb
->s_dev
;
25 stat
->ino
= inode
->i_ino
;
26 stat
->mode
= inode
->i_mode
;
27 stat
->nlink
= inode
->i_nlink
;
28 stat
->uid
= inode
->i_uid
;
29 stat
->gid
= inode
->i_gid
;
30 stat
->rdev
= inode
->i_rdev
;
31 stat
->size
= i_size_read(inode
);
32 stat
->atime
= inode
->i_atime
;
33 stat
->mtime
= inode
->i_mtime
;
34 stat
->ctime
= inode
->i_ctime
;
35 stat
->blksize
= i_blocksize(inode
);
36 stat
->blocks
= inode
->i_blocks
;
39 EXPORT_SYMBOL(generic_fillattr
);
42 * vfs_getattr_nosec - getattr without security checks
43 * @path: file to get attributes from
44 * @stat: structure to return attributes in
46 * Get attributes without calling security_inode_getattr.
48 * Currently the only caller other than vfs_getattr is internal to the
49 * filehandle lookup code, which uses only the inode number and returns
50 * no attributes to any user. Any other code probably wants
53 int vfs_getattr_nosec(struct path
*path
, struct kstat
*stat
)
55 struct inode
*inode
= d_backing_inode(path
->dentry
);
57 if (inode
->i_op
->getattr
)
58 return inode
->i_op
->getattr(path
->mnt
, path
->dentry
, stat
);
60 generic_fillattr(inode
, stat
);
64 EXPORT_SYMBOL(vfs_getattr_nosec
);
66 int vfs_getattr(struct path
*path
, struct kstat
*stat
)
70 retval
= security_inode_getattr(path
);
73 return vfs_getattr_nosec(path
, stat
);
76 EXPORT_SYMBOL(vfs_getattr
);
78 int vfs_fstat(unsigned int fd
, struct kstat
*stat
)
80 struct fd f
= fdget_raw(fd
);
84 error
= vfs_getattr(&f
.file
->f_path
, stat
);
89 EXPORT_SYMBOL(vfs_fstat
);
91 int vfs_fstatat(int dfd
, const char __user
*filename
, struct kstat
*stat
,
96 unsigned int lookup_flags
= 0;
98 if ((flag
& ~(AT_SYMLINK_NOFOLLOW
| AT_NO_AUTOMOUNT
|
102 if (!(flag
& AT_SYMLINK_NOFOLLOW
))
103 lookup_flags
|= LOOKUP_FOLLOW
;
104 if (flag
& AT_EMPTY_PATH
)
105 lookup_flags
|= LOOKUP_EMPTY
;
107 error
= user_path_at(dfd
, filename
, lookup_flags
, &path
);
111 error
= vfs_getattr(&path
, stat
);
113 if (retry_estale(error
, lookup_flags
)) {
114 lookup_flags
|= LOOKUP_REVAL
;
120 EXPORT_SYMBOL(vfs_fstatat
);
122 int vfs_stat(const char __user
*name
, struct kstat
*stat
)
124 return vfs_fstatat(AT_FDCWD
, name
, stat
, 0);
126 EXPORT_SYMBOL(vfs_stat
);
128 int vfs_lstat(const char __user
*name
, struct kstat
*stat
)
130 return vfs_fstatat(AT_FDCWD
, name
, stat
, AT_SYMLINK_NOFOLLOW
);
132 EXPORT_SYMBOL(vfs_lstat
);
135 #ifdef __ARCH_WANT_OLD_STAT
138 * For backward compatibility? Maybe this should be moved
139 * into arch/i386 instead?
141 static int cp_old_stat(struct kstat
*stat
, struct __old_kernel_stat __user
* statbuf
)
143 static int warncount
= 5;
144 struct __old_kernel_stat tmp
;
148 printk(KERN_WARNING
"VFS: Warning: %s using old stat() call. Recompile your binary.\n",
150 } else if (warncount
< 0) {
151 /* it's laughable, but... */
155 memset(&tmp
, 0, sizeof(struct __old_kernel_stat
));
156 tmp
.st_dev
= old_encode_dev(stat
->dev
);
157 tmp
.st_ino
= stat
->ino
;
158 if (sizeof(tmp
.st_ino
) < sizeof(stat
->ino
) && tmp
.st_ino
!= stat
->ino
)
160 tmp
.st_mode
= stat
->mode
;
161 tmp
.st_nlink
= stat
->nlink
;
162 if (tmp
.st_nlink
!= stat
->nlink
)
164 SET_UID(tmp
.st_uid
, from_kuid_munged(current_user_ns(), stat
->uid
));
165 SET_GID(tmp
.st_gid
, from_kgid_munged(current_user_ns(), stat
->gid
));
166 tmp
.st_rdev
= old_encode_dev(stat
->rdev
);
167 #if BITS_PER_LONG == 32
168 if (stat
->size
> MAX_NON_LFS
)
171 tmp
.st_size
= stat
->size
;
172 tmp
.st_atime
= stat
->atime
.tv_sec
;
173 tmp
.st_mtime
= stat
->mtime
.tv_sec
;
174 tmp
.st_ctime
= stat
->ctime
.tv_sec
;
175 return copy_to_user(statbuf
,&tmp
,sizeof(tmp
)) ? -EFAULT
: 0;
178 SYSCALL_DEFINE2(stat
, const char __user
*, filename
,
179 struct __old_kernel_stat __user
*, statbuf
)
184 error
= vfs_stat(filename
, &stat
);
188 return cp_old_stat(&stat
, statbuf
);
191 SYSCALL_DEFINE2(lstat
, const char __user
*, filename
,
192 struct __old_kernel_stat __user
*, statbuf
)
197 error
= vfs_lstat(filename
, &stat
);
201 return cp_old_stat(&stat
, statbuf
);
204 SYSCALL_DEFINE2(fstat
, unsigned int, fd
, struct __old_kernel_stat __user
*, statbuf
)
207 int error
= vfs_fstat(fd
, &stat
);
210 error
= cp_old_stat(&stat
, statbuf
);
215 #endif /* __ARCH_WANT_OLD_STAT */
217 #if BITS_PER_LONG == 32
218 # define choose_32_64(a,b) a
220 # define choose_32_64(a,b) b
223 #define valid_dev(x) choose_32_64(old_valid_dev(x),true)
224 #define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
226 #ifndef INIT_STRUCT_STAT_PADDING
227 # define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
230 static int cp_new_stat(struct kstat
*stat
, struct stat __user
*statbuf
)
234 if (!valid_dev(stat
->dev
) || !valid_dev(stat
->rdev
))
236 #if BITS_PER_LONG == 32
237 if (stat
->size
> MAX_NON_LFS
)
241 INIT_STRUCT_STAT_PADDING(tmp
);
242 tmp
.st_dev
= encode_dev(stat
->dev
);
243 tmp
.st_ino
= stat
->ino
;
244 if (sizeof(tmp
.st_ino
) < sizeof(stat
->ino
) && tmp
.st_ino
!= stat
->ino
)
246 tmp
.st_mode
= stat
->mode
;
247 tmp
.st_nlink
= stat
->nlink
;
248 if (tmp
.st_nlink
!= stat
->nlink
)
250 SET_UID(tmp
.st_uid
, from_kuid_munged(current_user_ns(), stat
->uid
));
251 SET_GID(tmp
.st_gid
, from_kgid_munged(current_user_ns(), stat
->gid
));
252 tmp
.st_rdev
= encode_dev(stat
->rdev
);
253 tmp
.st_size
= stat
->size
;
254 tmp
.st_atime
= stat
->atime
.tv_sec
;
255 tmp
.st_mtime
= stat
->mtime
.tv_sec
;
256 tmp
.st_ctime
= stat
->ctime
.tv_sec
;
257 #ifdef STAT_HAVE_NSEC
258 tmp
.st_atime_nsec
= stat
->atime
.tv_nsec
;
259 tmp
.st_mtime_nsec
= stat
->mtime
.tv_nsec
;
260 tmp
.st_ctime_nsec
= stat
->ctime
.tv_nsec
;
262 tmp
.st_blocks
= stat
->blocks
;
263 tmp
.st_blksize
= stat
->blksize
;
264 return copy_to_user(statbuf
,&tmp
,sizeof(tmp
)) ? -EFAULT
: 0;
267 SYSCALL_DEFINE2(newstat
, const char __user
*, filename
,
268 struct stat __user
*, statbuf
)
271 int error
= vfs_stat(filename
, &stat
);
275 return cp_new_stat(&stat
, statbuf
);
278 SYSCALL_DEFINE2(newlstat
, const char __user
*, filename
,
279 struct stat __user
*, statbuf
)
284 error
= vfs_lstat(filename
, &stat
);
288 return cp_new_stat(&stat
, statbuf
);
291 #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
292 SYSCALL_DEFINE4(newfstatat
, int, dfd
, const char __user
*, filename
,
293 struct stat __user
*, statbuf
, int, flag
)
298 error
= vfs_fstatat(dfd
, filename
, &stat
, flag
);
301 return cp_new_stat(&stat
, statbuf
);
305 SYSCALL_DEFINE2(newfstat
, unsigned int, fd
, struct stat __user
*, statbuf
)
308 int error
= vfs_fstat(fd
, &stat
);
311 error
= cp_new_stat(&stat
, statbuf
);
316 SYSCALL_DEFINE4(readlinkat
, int, dfd
, const char __user
*, pathname
,
317 char __user
*, buf
, int, bufsiz
)
322 unsigned int lookup_flags
= LOOKUP_EMPTY
;
328 error
= user_path_at_empty(dfd
, pathname
, lookup_flags
, &path
, &empty
);
330 struct inode
*inode
= d_backing_inode(path
.dentry
);
332 error
= empty
? -ENOENT
: -EINVAL
;
334 * AFS mountpoints allow readlink(2) but are not symlinks
336 if (d_is_symlink(path
.dentry
) || inode
->i_op
->readlink
) {
337 error
= security_inode_readlink(path
.dentry
);
340 error
= vfs_readlink(path
.dentry
, buf
, bufsiz
);
344 if (retry_estale(error
, lookup_flags
)) {
345 lookup_flags
|= LOOKUP_REVAL
;
352 SYSCALL_DEFINE3(readlink
, const char __user
*, path
, char __user
*, buf
,
355 return sys_readlinkat(AT_FDCWD
, path
, buf
, bufsiz
);
359 /* ---------- LFS-64 ----------- */
360 #if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
362 #ifndef INIT_STRUCT_STAT64_PADDING
363 # define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
366 static long cp_new_stat64(struct kstat
*stat
, struct stat64 __user
*statbuf
)
370 INIT_STRUCT_STAT64_PADDING(tmp
);
372 /* mips has weird padding, so we don't get 64 bits there */
373 tmp
.st_dev
= new_encode_dev(stat
->dev
);
374 tmp
.st_rdev
= new_encode_dev(stat
->rdev
);
376 tmp
.st_dev
= huge_encode_dev(stat
->dev
);
377 tmp
.st_rdev
= huge_encode_dev(stat
->rdev
);
379 tmp
.st_ino
= stat
->ino
;
380 if (sizeof(tmp
.st_ino
) < sizeof(stat
->ino
) && tmp
.st_ino
!= stat
->ino
)
382 #ifdef STAT64_HAS_BROKEN_ST_INO
383 tmp
.__st_ino
= stat
->ino
;
385 tmp
.st_mode
= stat
->mode
;
386 tmp
.st_nlink
= stat
->nlink
;
387 tmp
.st_uid
= from_kuid_munged(current_user_ns(), stat
->uid
);
388 tmp
.st_gid
= from_kgid_munged(current_user_ns(), stat
->gid
);
389 tmp
.st_atime
= stat
->atime
.tv_sec
;
390 tmp
.st_atime_nsec
= stat
->atime
.tv_nsec
;
391 tmp
.st_mtime
= stat
->mtime
.tv_sec
;
392 tmp
.st_mtime_nsec
= stat
->mtime
.tv_nsec
;
393 tmp
.st_ctime
= stat
->ctime
.tv_sec
;
394 tmp
.st_ctime_nsec
= stat
->ctime
.tv_nsec
;
395 tmp
.st_size
= stat
->size
;
396 tmp
.st_blocks
= stat
->blocks
;
397 tmp
.st_blksize
= stat
->blksize
;
398 return copy_to_user(statbuf
,&tmp
,sizeof(tmp
)) ? -EFAULT
: 0;
401 SYSCALL_DEFINE2(stat64
, const char __user
*, filename
,
402 struct stat64 __user
*, statbuf
)
405 int error
= vfs_stat(filename
, &stat
);
408 error
= cp_new_stat64(&stat
, statbuf
);
413 SYSCALL_DEFINE2(lstat64
, const char __user
*, filename
,
414 struct stat64 __user
*, statbuf
)
417 int error
= vfs_lstat(filename
, &stat
);
420 error
= cp_new_stat64(&stat
, statbuf
);
425 SYSCALL_DEFINE2(fstat64
, unsigned long, fd
, struct stat64 __user
*, statbuf
)
428 int error
= vfs_fstat(fd
, &stat
);
431 error
= cp_new_stat64(&stat
, statbuf
);
436 SYSCALL_DEFINE4(fstatat64
, int, dfd
, const char __user
*, filename
,
437 struct stat64 __user
*, statbuf
, int, flag
)
442 error
= vfs_fstatat(dfd
, filename
, &stat
, flag
);
445 return cp_new_stat64(&stat
, statbuf
);
447 #endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
449 /* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
450 void __inode_add_bytes(struct inode
*inode
, loff_t bytes
)
452 inode
->i_blocks
+= bytes
>> 9;
454 inode
->i_bytes
+= bytes
;
455 if (inode
->i_bytes
>= 512) {
457 inode
->i_bytes
-= 512;
461 void inode_add_bytes(struct inode
*inode
, loff_t bytes
)
463 spin_lock(&inode
->i_lock
);
464 __inode_add_bytes(inode
, bytes
);
465 spin_unlock(&inode
->i_lock
);
468 EXPORT_SYMBOL(inode_add_bytes
);
470 void __inode_sub_bytes(struct inode
*inode
, loff_t bytes
)
472 inode
->i_blocks
-= bytes
>> 9;
474 if (inode
->i_bytes
< bytes
) {
476 inode
->i_bytes
+= 512;
478 inode
->i_bytes
-= bytes
;
481 EXPORT_SYMBOL(__inode_sub_bytes
);
483 void inode_sub_bytes(struct inode
*inode
, loff_t bytes
)
485 spin_lock(&inode
->i_lock
);
486 __inode_sub_bytes(inode
, bytes
);
487 spin_unlock(&inode
->i_lock
);
490 EXPORT_SYMBOL(inode_sub_bytes
);
492 loff_t
inode_get_bytes(struct inode
*inode
)
496 spin_lock(&inode
->i_lock
);
497 ret
= (((loff_t
)inode
->i_blocks
) << 9) + inode
->i_bytes
;
498 spin_unlock(&inode
->i_lock
);
502 EXPORT_SYMBOL(inode_get_bytes
);
504 void inode_set_bytes(struct inode
*inode
, loff_t bytes
)
506 /* Caller is here responsible for sufficient locking
507 * (ie. inode->i_lock) */
508 inode
->i_blocks
= bytes
>> 9;
509 inode
->i_bytes
= bytes
& 511;
512 EXPORT_SYMBOL(inode_set_bytes
);