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; | |
30 | stat->atime = inode->i_atime; | |
31 | stat->mtime = inode->i_mtime; | |
32 | stat->ctime = inode->i_ctime; | |
33 | stat->size = i_size_read(inode); | |
34 | stat->blocks = inode->i_blocks; | |
ba52de12 | 35 | stat->blksize = (1 << inode->i_blkbits); |
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 | ||
5590ff0d | 58 | int vfs_stat_fd(int dfd, char __user *name, struct kstat *stat) |
1da177e4 | 59 | { |
2d8f3038 | 60 | struct path path; |
1da177e4 LT |
61 | int error; |
62 | ||
2d8f3038 | 63 | error = user_path_at(dfd, name, LOOKUP_FOLLOW, &path); |
1da177e4 | 64 | if (!error) { |
2d8f3038 AV |
65 | error = vfs_getattr(path.mnt, path.dentry, stat); |
66 | path_put(&path); | |
1da177e4 LT |
67 | } |
68 | return error; | |
69 | } | |
70 | ||
5590ff0d UD |
71 | int vfs_stat(char __user *name, struct kstat *stat) |
72 | { | |
73 | return vfs_stat_fd(AT_FDCWD, name, stat); | |
74 | } | |
75 | ||
1da177e4 LT |
76 | EXPORT_SYMBOL(vfs_stat); |
77 | ||
5590ff0d | 78 | int vfs_lstat_fd(int dfd, char __user *name, struct kstat *stat) |
1da177e4 | 79 | { |
2d8f3038 | 80 | struct path path; |
1da177e4 LT |
81 | int error; |
82 | ||
2d8f3038 | 83 | error = user_path_at(dfd, name, 0, &path); |
1da177e4 | 84 | if (!error) { |
2d8f3038 AV |
85 | error = vfs_getattr(path.mnt, path.dentry, stat); |
86 | path_put(&path); | |
1da177e4 LT |
87 | } |
88 | return error; | |
89 | } | |
90 | ||
5590ff0d UD |
91 | int vfs_lstat(char __user *name, struct kstat *stat) |
92 | { | |
93 | return vfs_lstat_fd(AT_FDCWD, name, stat); | |
94 | } | |
95 | ||
1da177e4 LT |
96 | EXPORT_SYMBOL(vfs_lstat); |
97 | ||
98 | int vfs_fstat(unsigned int fd, struct kstat *stat) | |
99 | { | |
100 | struct file *f = fget(fd); | |
101 | int error = -EBADF; | |
102 | ||
103 | if (f) { | |
0f7fc9e4 | 104 | error = vfs_getattr(f->f_path.mnt, f->f_path.dentry, stat); |
1da177e4 LT |
105 | fput(f); |
106 | } | |
107 | return error; | |
108 | } | |
109 | ||
110 | EXPORT_SYMBOL(vfs_fstat); | |
111 | ||
0112fc22 OD |
112 | int vfs_fstatat(int dfd, char __user *filename, struct kstat *stat, int flag) |
113 | { | |
114 | int error = -EINVAL; | |
115 | ||
116 | if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) | |
117 | goto out; | |
118 | ||
119 | if (flag & AT_SYMLINK_NOFOLLOW) | |
120 | error = vfs_lstat_fd(dfd, filename, stat); | |
121 | else | |
122 | error = vfs_stat_fd(dfd, filename, stat); | |
123 | out: | |
124 | return error; | |
125 | } | |
126 | ||
127 | EXPORT_SYMBOL(vfs_fstatat); | |
128 | ||
129 | ||
1da177e4 LT |
130 | #ifdef __ARCH_WANT_OLD_STAT |
131 | ||
132 | /* | |
133 | * For backward compatibility? Maybe this should be moved | |
134 | * into arch/i386 instead? | |
135 | */ | |
136 | static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf) | |
137 | { | |
138 | static int warncount = 5; | |
139 | struct __old_kernel_stat tmp; | |
140 | ||
141 | if (warncount > 0) { | |
142 | warncount--; | |
143 | printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n", | |
144 | current->comm); | |
145 | } else if (warncount < 0) { | |
146 | /* it's laughable, but... */ | |
147 | warncount = 0; | |
148 | } | |
149 | ||
150 | memset(&tmp, 0, sizeof(struct __old_kernel_stat)); | |
151 | tmp.st_dev = old_encode_dev(stat->dev); | |
152 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
153 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
154 | return -EOVERFLOW; | |
1da177e4 LT |
155 | tmp.st_mode = stat->mode; |
156 | tmp.st_nlink = stat->nlink; | |
157 | if (tmp.st_nlink != stat->nlink) | |
158 | return -EOVERFLOW; | |
159 | SET_UID(tmp.st_uid, stat->uid); | |
160 | SET_GID(tmp.st_gid, stat->gid); | |
161 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
162 | #if BITS_PER_LONG == 32 | |
163 | if (stat->size > MAX_NON_LFS) | |
164 | return -EOVERFLOW; | |
165 | #endif | |
166 | tmp.st_size = stat->size; | |
167 | tmp.st_atime = stat->atime.tv_sec; | |
168 | tmp.st_mtime = stat->mtime.tv_sec; | |
169 | tmp.st_ctime = stat->ctime.tv_sec; | |
170 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
171 | } | |
172 | ||
bdc480e3 | 173 | SYSCALL_DEFINE2(stat, char __user *, filename, struct __old_kernel_stat __user *, statbuf) |
1da177e4 LT |
174 | { |
175 | struct kstat stat; | |
5590ff0d | 176 | int error = vfs_stat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
177 | |
178 | if (!error) | |
179 | error = cp_old_stat(&stat, statbuf); | |
180 | ||
181 | return error; | |
182 | } | |
257ac264 HC |
183 | |
184 | SYSCALL_DEFINE2(lstat, char __user *, filename, struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
185 | { |
186 | struct kstat stat; | |
5590ff0d | 187 | int error = vfs_lstat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
188 | |
189 | if (!error) | |
190 | error = cp_old_stat(&stat, statbuf); | |
191 | ||
192 | return error; | |
193 | } | |
257ac264 HC |
194 | |
195 | SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
196 | { |
197 | struct kstat stat; | |
198 | int error = vfs_fstat(fd, &stat); | |
199 | ||
200 | if (!error) | |
201 | error = cp_old_stat(&stat, statbuf); | |
202 | ||
203 | return error; | |
204 | } | |
205 | ||
206 | #endif /* __ARCH_WANT_OLD_STAT */ | |
207 | ||
208 | static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) | |
209 | { | |
210 | struct stat tmp; | |
211 | ||
212 | #if BITS_PER_LONG == 32 | |
213 | if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev)) | |
214 | return -EOVERFLOW; | |
215 | #else | |
216 | if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev)) | |
217 | return -EOVERFLOW; | |
218 | #endif | |
219 | ||
220 | memset(&tmp, 0, sizeof(tmp)); | |
221 | #if BITS_PER_LONG == 32 | |
222 | tmp.st_dev = old_encode_dev(stat->dev); | |
223 | #else | |
224 | tmp.st_dev = new_encode_dev(stat->dev); | |
225 | #endif | |
226 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
227 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
228 | return -EOVERFLOW; | |
1da177e4 LT |
229 | tmp.st_mode = stat->mode; |
230 | tmp.st_nlink = stat->nlink; | |
231 | if (tmp.st_nlink != stat->nlink) | |
232 | return -EOVERFLOW; | |
233 | SET_UID(tmp.st_uid, stat->uid); | |
234 | SET_GID(tmp.st_gid, stat->gid); | |
235 | #if BITS_PER_LONG == 32 | |
236 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
237 | #else | |
238 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
239 | #endif | |
240 | #if BITS_PER_LONG == 32 | |
241 | if (stat->size > MAX_NON_LFS) | |
242 | return -EOVERFLOW; | |
243 | #endif | |
244 | tmp.st_size = stat->size; | |
245 | tmp.st_atime = stat->atime.tv_sec; | |
246 | tmp.st_mtime = stat->mtime.tv_sec; | |
247 | tmp.st_ctime = stat->ctime.tv_sec; | |
248 | #ifdef STAT_HAVE_NSEC | |
249 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
250 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
251 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
252 | #endif | |
253 | tmp.st_blocks = stat->blocks; | |
254 | tmp.st_blksize = stat->blksize; | |
255 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
256 | } | |
257 | ||
257ac264 | 258 | SYSCALL_DEFINE2(newstat, char __user *, filename, struct stat __user *, statbuf) |
5590ff0d UD |
259 | { |
260 | struct kstat stat; | |
261 | int error = vfs_stat_fd(AT_FDCWD, filename, &stat); | |
262 | ||
263 | if (!error) | |
264 | error = cp_new_stat(&stat, statbuf); | |
265 | ||
266 | return error; | |
267 | } | |
268 | ||
257ac264 | 269 | SYSCALL_DEFINE2(newlstat, char __user *, filename, struct stat __user *, statbuf) |
1da177e4 LT |
270 | { |
271 | struct kstat stat; | |
5590ff0d | 272 | int error = vfs_lstat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
273 | |
274 | if (!error) | |
275 | error = cp_new_stat(&stat, statbuf); | |
276 | ||
277 | return error; | |
278 | } | |
5590ff0d | 279 | |
2833c28a | 280 | #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT) |
6559eed8 HC |
281 | SYSCALL_DEFINE4(newfstatat, int, dfd, char __user *, filename, |
282 | struct stat __user *, statbuf, int, flag) | |
1da177e4 LT |
283 | { |
284 | struct kstat stat; | |
0112fc22 | 285 | int error; |
1da177e4 | 286 | |
0112fc22 OD |
287 | error = vfs_fstatat(dfd, filename, &stat, flag); |
288 | if (error) | |
289 | return error; | |
290 | return cp_new_stat(&stat, statbuf); | |
1da177e4 | 291 | } |
cff2b760 | 292 | #endif |
5590ff0d | 293 | |
257ac264 | 294 | SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf) |
1da177e4 LT |
295 | { |
296 | struct kstat stat; | |
297 | int error = vfs_fstat(fd, &stat); | |
298 | ||
299 | if (!error) | |
300 | error = cp_new_stat(&stat, statbuf); | |
301 | ||
302 | return error; | |
303 | } | |
304 | ||
6559eed8 HC |
305 | SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname, |
306 | char __user *, buf, int, bufsiz) | |
1da177e4 | 307 | { |
2d8f3038 | 308 | struct path path; |
1da177e4 LT |
309 | int error; |
310 | ||
311 | if (bufsiz <= 0) | |
312 | return -EINVAL; | |
313 | ||
2d8f3038 | 314 | error = user_path_at(dfd, pathname, 0, &path); |
1da177e4 | 315 | if (!error) { |
2d8f3038 | 316 | struct inode *inode = path.dentry->d_inode; |
1da177e4 LT |
317 | |
318 | error = -EINVAL; | |
acfa4380 | 319 | if (inode->i_op->readlink) { |
2d8f3038 | 320 | error = security_inode_readlink(path.dentry); |
1da177e4 | 321 | if (!error) { |
2d8f3038 AV |
322 | touch_atime(path.mnt, path.dentry); |
323 | error = inode->i_op->readlink(path.dentry, | |
4ac91378 | 324 | buf, bufsiz); |
1da177e4 LT |
325 | } |
326 | } | |
2d8f3038 | 327 | path_put(&path); |
1da177e4 LT |
328 | } |
329 | return error; | |
330 | } | |
331 | ||
002c8976 HC |
332 | SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf, |
333 | int, bufsiz) | |
5590ff0d UD |
334 | { |
335 | return sys_readlinkat(AT_FDCWD, path, buf, bufsiz); | |
336 | } | |
337 | ||
1da177e4 LT |
338 | |
339 | /* ---------- LFS-64 ----------- */ | |
340 | #ifdef __ARCH_WANT_STAT64 | |
341 | ||
342 | static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf) | |
343 | { | |
344 | struct stat64 tmp; | |
345 | ||
346 | memset(&tmp, 0, sizeof(struct stat64)); | |
347 | #ifdef CONFIG_MIPS | |
348 | /* mips has weird padding, so we don't get 64 bits there */ | |
349 | if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev)) | |
350 | return -EOVERFLOW; | |
351 | tmp.st_dev = new_encode_dev(stat->dev); | |
352 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
353 | #else | |
354 | tmp.st_dev = huge_encode_dev(stat->dev); | |
355 | tmp.st_rdev = huge_encode_dev(stat->rdev); | |
356 | #endif | |
357 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
358 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
359 | return -EOVERFLOW; | |
1da177e4 LT |
360 | #ifdef STAT64_HAS_BROKEN_ST_INO |
361 | tmp.__st_ino = stat->ino; | |
362 | #endif | |
363 | tmp.st_mode = stat->mode; | |
364 | tmp.st_nlink = stat->nlink; | |
365 | tmp.st_uid = stat->uid; | |
366 | tmp.st_gid = stat->gid; | |
367 | tmp.st_atime = stat->atime.tv_sec; | |
368 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
369 | tmp.st_mtime = stat->mtime.tv_sec; | |
370 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
371 | tmp.st_ctime = stat->ctime.tv_sec; | |
372 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
373 | tmp.st_size = stat->size; | |
374 | tmp.st_blocks = stat->blocks; | |
375 | tmp.st_blksize = stat->blksize; | |
376 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
377 | } | |
378 | ||
257ac264 | 379 | SYSCALL_DEFINE2(stat64, char __user *, filename, struct stat64 __user *, statbuf) |
1da177e4 LT |
380 | { |
381 | struct kstat stat; | |
382 | int error = vfs_stat(filename, &stat); | |
383 | ||
384 | if (!error) | |
385 | error = cp_new_stat64(&stat, statbuf); | |
386 | ||
387 | return error; | |
388 | } | |
257ac264 HC |
389 | |
390 | SYSCALL_DEFINE2(lstat64, char __user *, filename, struct stat64 __user *, statbuf) | |
1da177e4 LT |
391 | { |
392 | struct kstat stat; | |
393 | int error = vfs_lstat(filename, &stat); | |
394 | ||
395 | if (!error) | |
396 | error = cp_new_stat64(&stat, statbuf); | |
397 | ||
398 | return error; | |
399 | } | |
257ac264 HC |
400 | |
401 | SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf) | |
1da177e4 LT |
402 | { |
403 | struct kstat stat; | |
404 | int error = vfs_fstat(fd, &stat); | |
405 | ||
406 | if (!error) | |
407 | error = cp_new_stat64(&stat, statbuf); | |
408 | ||
409 | return error; | |
410 | } | |
411 | ||
6559eed8 HC |
412 | SYSCALL_DEFINE4(fstatat64, int, dfd, char __user *, filename, |
413 | struct stat64 __user *, statbuf, int, flag) | |
cff2b760 UD |
414 | { |
415 | struct kstat stat; | |
0112fc22 | 416 | int error; |
cff2b760 | 417 | |
0112fc22 OD |
418 | error = vfs_fstatat(dfd, filename, &stat, flag); |
419 | if (error) | |
420 | return error; | |
421 | return cp_new_stat64(&stat, statbuf); | |
cff2b760 | 422 | } |
1da177e4 LT |
423 | #endif /* __ARCH_WANT_STAT64 */ |
424 | ||
425 | void inode_add_bytes(struct inode *inode, loff_t bytes) | |
426 | { | |
427 | spin_lock(&inode->i_lock); | |
428 | inode->i_blocks += bytes >> 9; | |
429 | bytes &= 511; | |
430 | inode->i_bytes += bytes; | |
431 | if (inode->i_bytes >= 512) { | |
432 | inode->i_blocks++; | |
433 | inode->i_bytes -= 512; | |
434 | } | |
435 | spin_unlock(&inode->i_lock); | |
436 | } | |
437 | ||
438 | EXPORT_SYMBOL(inode_add_bytes); | |
439 | ||
440 | void inode_sub_bytes(struct inode *inode, loff_t bytes) | |
441 | { | |
442 | spin_lock(&inode->i_lock); | |
443 | inode->i_blocks -= bytes >> 9; | |
444 | bytes &= 511; | |
445 | if (inode->i_bytes < bytes) { | |
446 | inode->i_blocks--; | |
447 | inode->i_bytes += 512; | |
448 | } | |
449 | inode->i_bytes -= bytes; | |
450 | spin_unlock(&inode->i_lock); | |
451 | } | |
452 | ||
453 | EXPORT_SYMBOL(inode_sub_bytes); | |
454 | ||
455 | loff_t inode_get_bytes(struct inode *inode) | |
456 | { | |
457 | loff_t ret; | |
458 | ||
459 | spin_lock(&inode->i_lock); | |
460 | ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes; | |
461 | spin_unlock(&inode->i_lock); | |
462 | return ret; | |
463 | } | |
464 | ||
465 | EXPORT_SYMBOL(inode_get_bytes); | |
466 | ||
467 | void inode_set_bytes(struct inode *inode, loff_t bytes) | |
468 | { | |
469 | /* Caller is here responsible for sufficient locking | |
470 | * (ie. inode->i_lock) */ | |
471 | inode->i_blocks = bytes >> 9; | |
472 | inode->i_bytes = bytes & 511; | |
473 | } | |
474 | ||
475 | EXPORT_SYMBOL(inode_set_bytes); |