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Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/stat.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
1da177e4 LT |
7 | #include <linux/module.h> |
8 | #include <linux/mm.h> | |
9 | #include <linux/errno.h> | |
10 | #include <linux/file.h> | |
1da177e4 LT |
11 | #include <linux/highuid.h> |
12 | #include <linux/fs.h> | |
13 | #include <linux/namei.h> | |
14 | #include <linux/security.h> | |
15 | #include <linux/syscalls.h> | |
ba52de12 | 16 | #include <linux/pagemap.h> |
1da177e4 LT |
17 | |
18 | #include <asm/uaccess.h> | |
19 | #include <asm/unistd.h> | |
20 | ||
21 | void generic_fillattr(struct inode *inode, struct kstat *stat) | |
22 | { | |
23 | stat->dev = inode->i_sb->s_dev; | |
24 | stat->ino = inode->i_ino; | |
25 | stat->mode = inode->i_mode; | |
26 | stat->nlink = inode->i_nlink; | |
27 | stat->uid = inode->i_uid; | |
28 | stat->gid = inode->i_gid; | |
29 | stat->rdev = inode->i_rdev; | |
3ddcd056 | 30 | stat->size = i_size_read(inode); |
1da177e4 LT |
31 | stat->atime = inode->i_atime; |
32 | stat->mtime = inode->i_mtime; | |
33 | stat->ctime = inode->i_ctime; | |
ba52de12 | 34 | stat->blksize = (1 << inode->i_blkbits); |
3ddcd056 | 35 | stat->blocks = inode->i_blocks; |
1da177e4 LT |
36 | } |
37 | ||
38 | EXPORT_SYMBOL(generic_fillattr); | |
39 | ||
40 | int vfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) | |
41 | { | |
42 | struct inode *inode = dentry->d_inode; | |
43 | int retval; | |
44 | ||
45 | retval = security_inode_getattr(mnt, dentry); | |
46 | if (retval) | |
47 | return retval; | |
48 | ||
49 | if (inode->i_op->getattr) | |
50 | return inode->i_op->getattr(mnt, dentry, stat); | |
51 | ||
52 | generic_fillattr(inode, stat); | |
1da177e4 LT |
53 | return 0; |
54 | } | |
55 | ||
56 | EXPORT_SYMBOL(vfs_getattr); | |
57 | ||
1da177e4 LT |
58 | int vfs_fstat(unsigned int fd, struct kstat *stat) |
59 | { | |
60 | struct file *f = fget(fd); | |
61 | int error = -EBADF; | |
62 | ||
63 | if (f) { | |
0f7fc9e4 | 64 | error = vfs_getattr(f->f_path.mnt, f->f_path.dentry, stat); |
1da177e4 LT |
65 | fput(f); |
66 | } | |
67 | return error; | |
68 | } | |
1da177e4 LT |
69 | EXPORT_SYMBOL(vfs_fstat); |
70 | ||
c7887325 DH |
71 | int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat, |
72 | int flag) | |
0112fc22 | 73 | { |
2eae7a18 | 74 | struct path path; |
0112fc22 | 75 | int error = -EINVAL; |
2eae7a18 | 76 | int lookup_flags = 0; |
0112fc22 | 77 | |
65cfc672 AV |
78 | if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT | |
79 | AT_EMPTY_PATH)) != 0) | |
0112fc22 OD |
80 | goto out; |
81 | ||
2eae7a18 CH |
82 | if (!(flag & AT_SYMLINK_NOFOLLOW)) |
83 | lookup_flags |= LOOKUP_FOLLOW; | |
65cfc672 AV |
84 | if (flag & AT_EMPTY_PATH) |
85 | lookup_flags |= LOOKUP_EMPTY; | |
2eae7a18 CH |
86 | |
87 | error = user_path_at(dfd, filename, lookup_flags, &path); | |
88 | if (error) | |
89 | goto out; | |
90 | ||
91 | error = vfs_getattr(path.mnt, path.dentry, stat); | |
92 | path_put(&path); | |
0112fc22 OD |
93 | out: |
94 | return error; | |
95 | } | |
0112fc22 OD |
96 | EXPORT_SYMBOL(vfs_fstatat); |
97 | ||
c7887325 | 98 | int vfs_stat(const char __user *name, struct kstat *stat) |
2eae7a18 CH |
99 | { |
100 | return vfs_fstatat(AT_FDCWD, name, stat, 0); | |
101 | } | |
102 | EXPORT_SYMBOL(vfs_stat); | |
103 | ||
c7887325 | 104 | int vfs_lstat(const char __user *name, struct kstat *stat) |
2eae7a18 CH |
105 | { |
106 | return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW); | |
107 | } | |
108 | EXPORT_SYMBOL(vfs_lstat); | |
109 | ||
0112fc22 | 110 | |
1da177e4 LT |
111 | #ifdef __ARCH_WANT_OLD_STAT |
112 | ||
113 | /* | |
114 | * For backward compatibility? Maybe this should be moved | |
115 | * into arch/i386 instead? | |
116 | */ | |
117 | static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf) | |
118 | { | |
119 | static int warncount = 5; | |
120 | struct __old_kernel_stat tmp; | |
121 | ||
122 | if (warncount > 0) { | |
123 | warncount--; | |
124 | printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n", | |
125 | current->comm); | |
126 | } else if (warncount < 0) { | |
127 | /* it's laughable, but... */ | |
128 | warncount = 0; | |
129 | } | |
130 | ||
131 | memset(&tmp, 0, sizeof(struct __old_kernel_stat)); | |
132 | tmp.st_dev = old_encode_dev(stat->dev); | |
133 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
134 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
135 | return -EOVERFLOW; | |
1da177e4 LT |
136 | tmp.st_mode = stat->mode; |
137 | tmp.st_nlink = stat->nlink; | |
138 | if (tmp.st_nlink != stat->nlink) | |
139 | return -EOVERFLOW; | |
140 | SET_UID(tmp.st_uid, stat->uid); | |
141 | SET_GID(tmp.st_gid, stat->gid); | |
142 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
143 | #if BITS_PER_LONG == 32 | |
144 | if (stat->size > MAX_NON_LFS) | |
145 | return -EOVERFLOW; | |
146 | #endif | |
147 | tmp.st_size = stat->size; | |
148 | tmp.st_atime = stat->atime.tv_sec; | |
149 | tmp.st_mtime = stat->mtime.tv_sec; | |
150 | tmp.st_ctime = stat->ctime.tv_sec; | |
151 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
152 | } | |
153 | ||
c7887325 DH |
154 | SYSCALL_DEFINE2(stat, const char __user *, filename, |
155 | struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
156 | { |
157 | struct kstat stat; | |
2eae7a18 | 158 | int error; |
1da177e4 | 159 | |
2eae7a18 CH |
160 | error = vfs_stat(filename, &stat); |
161 | if (error) | |
162 | return error; | |
1da177e4 | 163 | |
2eae7a18 | 164 | return cp_old_stat(&stat, statbuf); |
1da177e4 | 165 | } |
257ac264 | 166 | |
c7887325 DH |
167 | SYSCALL_DEFINE2(lstat, const char __user *, filename, |
168 | struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
169 | { |
170 | struct kstat stat; | |
2eae7a18 | 171 | int error; |
1da177e4 | 172 | |
2eae7a18 CH |
173 | error = vfs_lstat(filename, &stat); |
174 | if (error) | |
175 | return error; | |
1da177e4 | 176 | |
2eae7a18 | 177 | return cp_old_stat(&stat, statbuf); |
1da177e4 | 178 | } |
257ac264 HC |
179 | |
180 | SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
181 | { |
182 | struct kstat stat; | |
183 | int error = vfs_fstat(fd, &stat); | |
184 | ||
185 | if (!error) | |
186 | error = cp_old_stat(&stat, statbuf); | |
187 | ||
188 | return error; | |
189 | } | |
190 | ||
191 | #endif /* __ARCH_WANT_OLD_STAT */ | |
192 | ||
193 | static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) | |
194 | { | |
195 | struct stat tmp; | |
196 | ||
197 | #if BITS_PER_LONG == 32 | |
198 | if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev)) | |
199 | return -EOVERFLOW; | |
200 | #else | |
201 | if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev)) | |
202 | return -EOVERFLOW; | |
203 | #endif | |
204 | ||
205 | memset(&tmp, 0, sizeof(tmp)); | |
206 | #if BITS_PER_LONG == 32 | |
207 | tmp.st_dev = old_encode_dev(stat->dev); | |
208 | #else | |
209 | tmp.st_dev = new_encode_dev(stat->dev); | |
210 | #endif | |
211 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
212 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
213 | return -EOVERFLOW; | |
1da177e4 LT |
214 | tmp.st_mode = stat->mode; |
215 | tmp.st_nlink = stat->nlink; | |
216 | if (tmp.st_nlink != stat->nlink) | |
217 | return -EOVERFLOW; | |
218 | SET_UID(tmp.st_uid, stat->uid); | |
219 | SET_GID(tmp.st_gid, stat->gid); | |
220 | #if BITS_PER_LONG == 32 | |
221 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
222 | #else | |
223 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
224 | #endif | |
225 | #if BITS_PER_LONG == 32 | |
226 | if (stat->size > MAX_NON_LFS) | |
227 | return -EOVERFLOW; | |
228 | #endif | |
229 | tmp.st_size = stat->size; | |
230 | tmp.st_atime = stat->atime.tv_sec; | |
231 | tmp.st_mtime = stat->mtime.tv_sec; | |
232 | tmp.st_ctime = stat->ctime.tv_sec; | |
233 | #ifdef STAT_HAVE_NSEC | |
234 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
235 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
236 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
237 | #endif | |
238 | tmp.st_blocks = stat->blocks; | |
239 | tmp.st_blksize = stat->blksize; | |
240 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
241 | } | |
242 | ||
c7887325 DH |
243 | SYSCALL_DEFINE2(newstat, const char __user *, filename, |
244 | struct stat __user *, statbuf) | |
5590ff0d UD |
245 | { |
246 | struct kstat stat; | |
2eae7a18 | 247 | int error = vfs_stat(filename, &stat); |
5590ff0d | 248 | |
2eae7a18 CH |
249 | if (error) |
250 | return error; | |
251 | return cp_new_stat(&stat, statbuf); | |
5590ff0d UD |
252 | } |
253 | ||
c7887325 DH |
254 | SYSCALL_DEFINE2(newlstat, const char __user *, filename, |
255 | struct stat __user *, statbuf) | |
1da177e4 LT |
256 | { |
257 | struct kstat stat; | |
2eae7a18 | 258 | int error; |
1da177e4 | 259 | |
2eae7a18 CH |
260 | error = vfs_lstat(filename, &stat); |
261 | if (error) | |
262 | return error; | |
1da177e4 | 263 | |
2eae7a18 | 264 | return cp_new_stat(&stat, statbuf); |
1da177e4 | 265 | } |
5590ff0d | 266 | |
2833c28a | 267 | #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT) |
c7887325 | 268 | SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename, |
6559eed8 | 269 | struct stat __user *, statbuf, int, flag) |
1da177e4 LT |
270 | { |
271 | struct kstat stat; | |
0112fc22 | 272 | int error; |
1da177e4 | 273 | |
0112fc22 OD |
274 | error = vfs_fstatat(dfd, filename, &stat, flag); |
275 | if (error) | |
276 | return error; | |
277 | return cp_new_stat(&stat, statbuf); | |
1da177e4 | 278 | } |
cff2b760 | 279 | #endif |
5590ff0d | 280 | |
257ac264 | 281 | SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf) |
1da177e4 LT |
282 | { |
283 | struct kstat stat; | |
284 | int error = vfs_fstat(fd, &stat); | |
285 | ||
286 | if (!error) | |
287 | error = cp_new_stat(&stat, statbuf); | |
288 | ||
289 | return error; | |
290 | } | |
291 | ||
6559eed8 HC |
292 | SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname, |
293 | char __user *, buf, int, bufsiz) | |
1da177e4 | 294 | { |
2d8f3038 | 295 | struct path path; |
1da177e4 LT |
296 | int error; |
297 | ||
298 | if (bufsiz <= 0) | |
299 | return -EINVAL; | |
300 | ||
65cfc672 | 301 | error = user_path_at(dfd, pathname, LOOKUP_EMPTY, &path); |
1da177e4 | 302 | if (!error) { |
2d8f3038 | 303 | struct inode *inode = path.dentry->d_inode; |
1da177e4 LT |
304 | |
305 | error = -EINVAL; | |
acfa4380 | 306 | if (inode->i_op->readlink) { |
2d8f3038 | 307 | error = security_inode_readlink(path.dentry); |
1da177e4 | 308 | if (!error) { |
2d8f3038 AV |
309 | touch_atime(path.mnt, path.dentry); |
310 | error = inode->i_op->readlink(path.dentry, | |
4ac91378 | 311 | buf, bufsiz); |
1da177e4 LT |
312 | } |
313 | } | |
2d8f3038 | 314 | path_put(&path); |
1da177e4 LT |
315 | } |
316 | return error; | |
317 | } | |
318 | ||
002c8976 HC |
319 | SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf, |
320 | int, bufsiz) | |
5590ff0d UD |
321 | { |
322 | return sys_readlinkat(AT_FDCWD, path, buf, bufsiz); | |
323 | } | |
324 | ||
1da177e4 LT |
325 | |
326 | /* ---------- LFS-64 ----------- */ | |
327 | #ifdef __ARCH_WANT_STAT64 | |
328 | ||
329 | static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf) | |
330 | { | |
331 | struct stat64 tmp; | |
332 | ||
333 | memset(&tmp, 0, sizeof(struct stat64)); | |
334 | #ifdef CONFIG_MIPS | |
335 | /* mips has weird padding, so we don't get 64 bits there */ | |
336 | if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev)) | |
337 | return -EOVERFLOW; | |
338 | tmp.st_dev = new_encode_dev(stat->dev); | |
339 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
340 | #else | |
341 | tmp.st_dev = huge_encode_dev(stat->dev); | |
342 | tmp.st_rdev = huge_encode_dev(stat->rdev); | |
343 | #endif | |
344 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
345 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
346 | return -EOVERFLOW; | |
1da177e4 LT |
347 | #ifdef STAT64_HAS_BROKEN_ST_INO |
348 | tmp.__st_ino = stat->ino; | |
349 | #endif | |
350 | tmp.st_mode = stat->mode; | |
351 | tmp.st_nlink = stat->nlink; | |
352 | tmp.st_uid = stat->uid; | |
353 | tmp.st_gid = stat->gid; | |
354 | tmp.st_atime = stat->atime.tv_sec; | |
355 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
356 | tmp.st_mtime = stat->mtime.tv_sec; | |
357 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
358 | tmp.st_ctime = stat->ctime.tv_sec; | |
359 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
360 | tmp.st_size = stat->size; | |
361 | tmp.st_blocks = stat->blocks; | |
362 | tmp.st_blksize = stat->blksize; | |
363 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
364 | } | |
365 | ||
c7887325 DH |
366 | SYSCALL_DEFINE2(stat64, const char __user *, filename, |
367 | struct stat64 __user *, statbuf) | |
1da177e4 LT |
368 | { |
369 | struct kstat stat; | |
370 | int error = vfs_stat(filename, &stat); | |
371 | ||
372 | if (!error) | |
373 | error = cp_new_stat64(&stat, statbuf); | |
374 | ||
375 | return error; | |
376 | } | |
257ac264 | 377 | |
c7887325 DH |
378 | SYSCALL_DEFINE2(lstat64, const char __user *, filename, |
379 | struct stat64 __user *, statbuf) | |
1da177e4 LT |
380 | { |
381 | struct kstat stat; | |
382 | int error = vfs_lstat(filename, &stat); | |
383 | ||
384 | if (!error) | |
385 | error = cp_new_stat64(&stat, statbuf); | |
386 | ||
387 | return error; | |
388 | } | |
257ac264 HC |
389 | |
390 | SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf) | |
1da177e4 LT |
391 | { |
392 | struct kstat stat; | |
393 | int error = vfs_fstat(fd, &stat); | |
394 | ||
395 | if (!error) | |
396 | error = cp_new_stat64(&stat, statbuf); | |
397 | ||
398 | return error; | |
399 | } | |
400 | ||
c7887325 | 401 | SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename, |
6559eed8 | 402 | struct stat64 __user *, statbuf, int, flag) |
cff2b760 UD |
403 | { |
404 | struct kstat stat; | |
0112fc22 | 405 | int error; |
cff2b760 | 406 | |
0112fc22 OD |
407 | error = vfs_fstatat(dfd, filename, &stat, flag); |
408 | if (error) | |
409 | return error; | |
410 | return cp_new_stat64(&stat, statbuf); | |
cff2b760 | 411 | } |
1da177e4 LT |
412 | #endif /* __ARCH_WANT_STAT64 */ |
413 | ||
b462707e DM |
414 | /* Caller is here responsible for sufficient locking (ie. inode->i_lock) */ |
415 | void __inode_add_bytes(struct inode *inode, loff_t bytes) | |
1da177e4 | 416 | { |
1da177e4 LT |
417 | inode->i_blocks += bytes >> 9; |
418 | bytes &= 511; | |
419 | inode->i_bytes += bytes; | |
420 | if (inode->i_bytes >= 512) { | |
421 | inode->i_blocks++; | |
422 | inode->i_bytes -= 512; | |
423 | } | |
b462707e DM |
424 | } |
425 | ||
426 | void inode_add_bytes(struct inode *inode, loff_t bytes) | |
427 | { | |
428 | spin_lock(&inode->i_lock); | |
429 | __inode_add_bytes(inode, bytes); | |
1da177e4 LT |
430 | spin_unlock(&inode->i_lock); |
431 | } | |
432 | ||
433 | EXPORT_SYMBOL(inode_add_bytes); | |
434 | ||
435 | void inode_sub_bytes(struct inode *inode, loff_t bytes) | |
436 | { | |
437 | spin_lock(&inode->i_lock); | |
438 | inode->i_blocks -= bytes >> 9; | |
439 | bytes &= 511; | |
440 | if (inode->i_bytes < bytes) { | |
441 | inode->i_blocks--; | |
442 | inode->i_bytes += 512; | |
443 | } | |
444 | inode->i_bytes -= bytes; | |
445 | spin_unlock(&inode->i_lock); | |
446 | } | |
447 | ||
448 | EXPORT_SYMBOL(inode_sub_bytes); | |
449 | ||
450 | loff_t inode_get_bytes(struct inode *inode) | |
451 | { | |
452 | loff_t ret; | |
453 | ||
454 | spin_lock(&inode->i_lock); | |
455 | ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes; | |
456 | spin_unlock(&inode->i_lock); | |
457 | return ret; | |
458 | } | |
459 | ||
460 | EXPORT_SYMBOL(inode_get_bytes); | |
461 | ||
462 | void inode_set_bytes(struct inode *inode, loff_t bytes) | |
463 | { | |
464 | /* Caller is here responsible for sufficient locking | |
465 | * (ie. inode->i_lock) */ | |
466 | inode->i_blocks = bytes >> 9; | |
467 | inode->i_bytes = bytes & 511; | |
468 | } | |
469 | ||
470 | EXPORT_SYMBOL(inode_set_bytes); |