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 | ||
112 | #ifdef __ARCH_WANT_OLD_STAT | |
113 | ||
114 | /* | |
115 | * For backward compatibility? Maybe this should be moved | |
116 | * into arch/i386 instead? | |
117 | */ | |
118 | static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf) | |
119 | { | |
120 | static int warncount = 5; | |
121 | struct __old_kernel_stat tmp; | |
122 | ||
123 | if (warncount > 0) { | |
124 | warncount--; | |
125 | printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n", | |
126 | current->comm); | |
127 | } else if (warncount < 0) { | |
128 | /* it's laughable, but... */ | |
129 | warncount = 0; | |
130 | } | |
131 | ||
132 | memset(&tmp, 0, sizeof(struct __old_kernel_stat)); | |
133 | tmp.st_dev = old_encode_dev(stat->dev); | |
134 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
135 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
136 | return -EOVERFLOW; | |
1da177e4 LT |
137 | tmp.st_mode = stat->mode; |
138 | tmp.st_nlink = stat->nlink; | |
139 | if (tmp.st_nlink != stat->nlink) | |
140 | return -EOVERFLOW; | |
141 | SET_UID(tmp.st_uid, stat->uid); | |
142 | SET_GID(tmp.st_gid, stat->gid); | |
143 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
144 | #if BITS_PER_LONG == 32 | |
145 | if (stat->size > MAX_NON_LFS) | |
146 | return -EOVERFLOW; | |
147 | #endif | |
148 | tmp.st_size = stat->size; | |
149 | tmp.st_atime = stat->atime.tv_sec; | |
150 | tmp.st_mtime = stat->mtime.tv_sec; | |
151 | tmp.st_ctime = stat->ctime.tv_sec; | |
152 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
153 | } | |
154 | ||
bdc480e3 | 155 | SYSCALL_DEFINE2(stat, char __user *, filename, struct __old_kernel_stat __user *, statbuf) |
1da177e4 LT |
156 | { |
157 | struct kstat stat; | |
5590ff0d | 158 | int error = vfs_stat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
159 | |
160 | if (!error) | |
161 | error = cp_old_stat(&stat, statbuf); | |
162 | ||
163 | return error; | |
164 | } | |
257ac264 HC |
165 | |
166 | SYSCALL_DEFINE2(lstat, char __user *, filename, struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
167 | { |
168 | struct kstat stat; | |
5590ff0d | 169 | int error = vfs_lstat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
170 | |
171 | if (!error) | |
172 | error = cp_old_stat(&stat, statbuf); | |
173 | ||
174 | return error; | |
175 | } | |
257ac264 HC |
176 | |
177 | SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf) | |
1da177e4 LT |
178 | { |
179 | struct kstat stat; | |
180 | int error = vfs_fstat(fd, &stat); | |
181 | ||
182 | if (!error) | |
183 | error = cp_old_stat(&stat, statbuf); | |
184 | ||
185 | return error; | |
186 | } | |
187 | ||
188 | #endif /* __ARCH_WANT_OLD_STAT */ | |
189 | ||
190 | static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) | |
191 | { | |
192 | struct stat tmp; | |
193 | ||
194 | #if BITS_PER_LONG == 32 | |
195 | if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev)) | |
196 | return -EOVERFLOW; | |
197 | #else | |
198 | if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev)) | |
199 | return -EOVERFLOW; | |
200 | #endif | |
201 | ||
202 | memset(&tmp, 0, sizeof(tmp)); | |
203 | #if BITS_PER_LONG == 32 | |
204 | tmp.st_dev = old_encode_dev(stat->dev); | |
205 | #else | |
206 | tmp.st_dev = new_encode_dev(stat->dev); | |
207 | #endif | |
208 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
209 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
210 | return -EOVERFLOW; | |
1da177e4 LT |
211 | tmp.st_mode = stat->mode; |
212 | tmp.st_nlink = stat->nlink; | |
213 | if (tmp.st_nlink != stat->nlink) | |
214 | return -EOVERFLOW; | |
215 | SET_UID(tmp.st_uid, stat->uid); | |
216 | SET_GID(tmp.st_gid, stat->gid); | |
217 | #if BITS_PER_LONG == 32 | |
218 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
219 | #else | |
220 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
221 | #endif | |
222 | #if BITS_PER_LONG == 32 | |
223 | if (stat->size > MAX_NON_LFS) | |
224 | return -EOVERFLOW; | |
225 | #endif | |
226 | tmp.st_size = stat->size; | |
227 | tmp.st_atime = stat->atime.tv_sec; | |
228 | tmp.st_mtime = stat->mtime.tv_sec; | |
229 | tmp.st_ctime = stat->ctime.tv_sec; | |
230 | #ifdef STAT_HAVE_NSEC | |
231 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
232 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
233 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
234 | #endif | |
235 | tmp.st_blocks = stat->blocks; | |
236 | tmp.st_blksize = stat->blksize; | |
237 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
238 | } | |
239 | ||
257ac264 | 240 | SYSCALL_DEFINE2(newstat, char __user *, filename, struct stat __user *, statbuf) |
5590ff0d UD |
241 | { |
242 | struct kstat stat; | |
243 | int error = vfs_stat_fd(AT_FDCWD, filename, &stat); | |
244 | ||
245 | if (!error) | |
246 | error = cp_new_stat(&stat, statbuf); | |
247 | ||
248 | return error; | |
249 | } | |
250 | ||
257ac264 | 251 | SYSCALL_DEFINE2(newlstat, char __user *, filename, struct stat __user *, statbuf) |
1da177e4 LT |
252 | { |
253 | struct kstat stat; | |
5590ff0d | 254 | int error = vfs_lstat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
255 | |
256 | if (!error) | |
257 | error = cp_new_stat(&stat, statbuf); | |
258 | ||
259 | return error; | |
260 | } | |
5590ff0d | 261 | |
2833c28a | 262 | #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT) |
6559eed8 HC |
263 | SYSCALL_DEFINE4(newfstatat, int, dfd, char __user *, filename, |
264 | struct stat __user *, statbuf, int, flag) | |
1da177e4 LT |
265 | { |
266 | struct kstat stat; | |
5590ff0d UD |
267 | int error = -EINVAL; |
268 | ||
269 | if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) | |
270 | goto out; | |
271 | ||
272 | if (flag & AT_SYMLINK_NOFOLLOW) | |
273 | error = vfs_lstat_fd(dfd, filename, &stat); | |
274 | else | |
275 | error = vfs_stat_fd(dfd, filename, &stat); | |
1da177e4 LT |
276 | |
277 | if (!error) | |
278 | error = cp_new_stat(&stat, statbuf); | |
279 | ||
5590ff0d | 280 | out: |
1da177e4 LT |
281 | return error; |
282 | } | |
cff2b760 | 283 | #endif |
5590ff0d | 284 | |
257ac264 | 285 | SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf) |
1da177e4 LT |
286 | { |
287 | struct kstat stat; | |
288 | int error = vfs_fstat(fd, &stat); | |
289 | ||
290 | if (!error) | |
291 | error = cp_new_stat(&stat, statbuf); | |
292 | ||
293 | return error; | |
294 | } | |
295 | ||
6559eed8 HC |
296 | SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname, |
297 | char __user *, buf, int, bufsiz) | |
1da177e4 | 298 | { |
2d8f3038 | 299 | struct path path; |
1da177e4 LT |
300 | int error; |
301 | ||
302 | if (bufsiz <= 0) | |
303 | return -EINVAL; | |
304 | ||
2d8f3038 | 305 | error = user_path_at(dfd, pathname, 0, &path); |
1da177e4 | 306 | if (!error) { |
2d8f3038 | 307 | struct inode *inode = path.dentry->d_inode; |
1da177e4 LT |
308 | |
309 | error = -EINVAL; | |
acfa4380 | 310 | if (inode->i_op->readlink) { |
2d8f3038 | 311 | error = security_inode_readlink(path.dentry); |
1da177e4 | 312 | if (!error) { |
2d8f3038 AV |
313 | touch_atime(path.mnt, path.dentry); |
314 | error = inode->i_op->readlink(path.dentry, | |
4ac91378 | 315 | buf, bufsiz); |
1da177e4 LT |
316 | } |
317 | } | |
2d8f3038 | 318 | path_put(&path); |
1da177e4 LT |
319 | } |
320 | return error; | |
321 | } | |
322 | ||
002c8976 HC |
323 | SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf, |
324 | int, bufsiz) | |
5590ff0d UD |
325 | { |
326 | return sys_readlinkat(AT_FDCWD, path, buf, bufsiz); | |
327 | } | |
328 | ||
1da177e4 LT |
329 | |
330 | /* ---------- LFS-64 ----------- */ | |
331 | #ifdef __ARCH_WANT_STAT64 | |
332 | ||
333 | static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf) | |
334 | { | |
335 | struct stat64 tmp; | |
336 | ||
337 | memset(&tmp, 0, sizeof(struct stat64)); | |
338 | #ifdef CONFIG_MIPS | |
339 | /* mips has weird padding, so we don't get 64 bits there */ | |
340 | if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev)) | |
341 | return -EOVERFLOW; | |
342 | tmp.st_dev = new_encode_dev(stat->dev); | |
343 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
344 | #else | |
345 | tmp.st_dev = huge_encode_dev(stat->dev); | |
346 | tmp.st_rdev = huge_encode_dev(stat->rdev); | |
347 | #endif | |
348 | tmp.st_ino = stat->ino; | |
afefdbb2 DH |
349 | if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) |
350 | return -EOVERFLOW; | |
1da177e4 LT |
351 | #ifdef STAT64_HAS_BROKEN_ST_INO |
352 | tmp.__st_ino = stat->ino; | |
353 | #endif | |
354 | tmp.st_mode = stat->mode; | |
355 | tmp.st_nlink = stat->nlink; | |
356 | tmp.st_uid = stat->uid; | |
357 | tmp.st_gid = stat->gid; | |
358 | tmp.st_atime = stat->atime.tv_sec; | |
359 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
360 | tmp.st_mtime = stat->mtime.tv_sec; | |
361 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
362 | tmp.st_ctime = stat->ctime.tv_sec; | |
363 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
364 | tmp.st_size = stat->size; | |
365 | tmp.st_blocks = stat->blocks; | |
366 | tmp.st_blksize = stat->blksize; | |
367 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
368 | } | |
369 | ||
257ac264 | 370 | SYSCALL_DEFINE2(stat64, char __user *, filename, struct stat64 __user *, statbuf) |
1da177e4 LT |
371 | { |
372 | struct kstat stat; | |
373 | int error = vfs_stat(filename, &stat); | |
374 | ||
375 | if (!error) | |
376 | error = cp_new_stat64(&stat, statbuf); | |
377 | ||
378 | return error; | |
379 | } | |
257ac264 HC |
380 | |
381 | SYSCALL_DEFINE2(lstat64, char __user *, filename, struct stat64 __user *, statbuf) | |
1da177e4 LT |
382 | { |
383 | struct kstat stat; | |
384 | int error = vfs_lstat(filename, &stat); | |
385 | ||
386 | if (!error) | |
387 | error = cp_new_stat64(&stat, statbuf); | |
388 | ||
389 | return error; | |
390 | } | |
257ac264 HC |
391 | |
392 | SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf) | |
1da177e4 LT |
393 | { |
394 | struct kstat stat; | |
395 | int error = vfs_fstat(fd, &stat); | |
396 | ||
397 | if (!error) | |
398 | error = cp_new_stat64(&stat, statbuf); | |
399 | ||
400 | return error; | |
401 | } | |
402 | ||
6559eed8 HC |
403 | SYSCALL_DEFINE4(fstatat64, int, dfd, char __user *, filename, |
404 | struct stat64 __user *, statbuf, int, flag) | |
cff2b760 UD |
405 | { |
406 | struct kstat stat; | |
407 | int error = -EINVAL; | |
408 | ||
409 | if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) | |
410 | goto out; | |
411 | ||
412 | if (flag & AT_SYMLINK_NOFOLLOW) | |
413 | error = vfs_lstat_fd(dfd, filename, &stat); | |
414 | else | |
415 | error = vfs_stat_fd(dfd, filename, &stat); | |
416 | ||
417 | if (!error) | |
418 | error = cp_new_stat64(&stat, statbuf); | |
419 | ||
420 | out: | |
421 | return error; | |
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); |