]>
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> | |
11 | #include <linux/smp_lock.h> | |
12 | #include <linux/highuid.h> | |
13 | #include <linux/fs.h> | |
14 | #include <linux/namei.h> | |
15 | #include <linux/security.h> | |
16 | #include <linux/syscalls.h> | |
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; | |
35 | stat->blksize = inode->i_blksize; | |
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); | |
53 | if (!stat->blksize) { | |
54 | struct super_block *s = inode->i_sb; | |
55 | unsigned blocks; | |
56 | blocks = (stat->size+s->s_blocksize-1) >> s->s_blocksize_bits; | |
57 | stat->blocks = (s->s_blocksize / 512) * blocks; | |
58 | stat->blksize = s->s_blocksize; | |
59 | } | |
60 | return 0; | |
61 | } | |
62 | ||
63 | EXPORT_SYMBOL(vfs_getattr); | |
64 | ||
5590ff0d | 65 | int vfs_stat_fd(int dfd, char __user *name, struct kstat *stat) |
1da177e4 LT |
66 | { |
67 | struct nameidata nd; | |
68 | int error; | |
69 | ||
5590ff0d | 70 | error = __user_walk_fd(dfd, name, LOOKUP_FOLLOW, &nd); |
1da177e4 LT |
71 | if (!error) { |
72 | error = vfs_getattr(nd.mnt, nd.dentry, stat); | |
73 | path_release(&nd); | |
74 | } | |
75 | return error; | |
76 | } | |
77 | ||
5590ff0d UD |
78 | int vfs_stat(char __user *name, struct kstat *stat) |
79 | { | |
80 | return vfs_stat_fd(AT_FDCWD, name, stat); | |
81 | } | |
82 | ||
1da177e4 LT |
83 | EXPORT_SYMBOL(vfs_stat); |
84 | ||
5590ff0d | 85 | int vfs_lstat_fd(int dfd, char __user *name, struct kstat *stat) |
1da177e4 LT |
86 | { |
87 | struct nameidata nd; | |
88 | int error; | |
89 | ||
5590ff0d | 90 | error = __user_walk_fd(dfd, name, 0, &nd); |
1da177e4 LT |
91 | if (!error) { |
92 | error = vfs_getattr(nd.mnt, nd.dentry, stat); | |
93 | path_release(&nd); | |
94 | } | |
95 | return error; | |
96 | } | |
97 | ||
5590ff0d UD |
98 | int vfs_lstat(char __user *name, struct kstat *stat) |
99 | { | |
100 | return vfs_lstat_fd(AT_FDCWD, name, stat); | |
101 | } | |
102 | ||
1da177e4 LT |
103 | EXPORT_SYMBOL(vfs_lstat); |
104 | ||
105 | int vfs_fstat(unsigned int fd, struct kstat *stat) | |
106 | { | |
107 | struct file *f = fget(fd); | |
108 | int error = -EBADF; | |
109 | ||
110 | if (f) { | |
111 | error = vfs_getattr(f->f_vfsmnt, f->f_dentry, stat); | |
112 | fput(f); | |
113 | } | |
114 | return error; | |
115 | } | |
116 | ||
117 | EXPORT_SYMBOL(vfs_fstat); | |
118 | ||
119 | #ifdef __ARCH_WANT_OLD_STAT | |
120 | ||
121 | /* | |
122 | * For backward compatibility? Maybe this should be moved | |
123 | * into arch/i386 instead? | |
124 | */ | |
125 | static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf) | |
126 | { | |
127 | static int warncount = 5; | |
128 | struct __old_kernel_stat tmp; | |
129 | ||
130 | if (warncount > 0) { | |
131 | warncount--; | |
132 | printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n", | |
133 | current->comm); | |
134 | } else if (warncount < 0) { | |
135 | /* it's laughable, but... */ | |
136 | warncount = 0; | |
137 | } | |
138 | ||
139 | memset(&tmp, 0, sizeof(struct __old_kernel_stat)); | |
140 | tmp.st_dev = old_encode_dev(stat->dev); | |
141 | tmp.st_ino = stat->ino; | |
142 | tmp.st_mode = stat->mode; | |
143 | tmp.st_nlink = stat->nlink; | |
144 | if (tmp.st_nlink != stat->nlink) | |
145 | return -EOVERFLOW; | |
146 | SET_UID(tmp.st_uid, stat->uid); | |
147 | SET_GID(tmp.st_gid, stat->gid); | |
148 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
149 | #if BITS_PER_LONG == 32 | |
150 | if (stat->size > MAX_NON_LFS) | |
151 | return -EOVERFLOW; | |
152 | #endif | |
153 | tmp.st_size = stat->size; | |
154 | tmp.st_atime = stat->atime.tv_sec; | |
155 | tmp.st_mtime = stat->mtime.tv_sec; | |
156 | tmp.st_ctime = stat->ctime.tv_sec; | |
157 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
158 | } | |
159 | ||
160 | asmlinkage long sys_stat(char __user * filename, struct __old_kernel_stat __user * statbuf) | |
161 | { | |
162 | struct kstat stat; | |
5590ff0d | 163 | int error = vfs_stat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
164 | |
165 | if (!error) | |
166 | error = cp_old_stat(&stat, statbuf); | |
167 | ||
168 | return error; | |
169 | } | |
170 | asmlinkage long sys_lstat(char __user * filename, struct __old_kernel_stat __user * statbuf) | |
171 | { | |
172 | struct kstat stat; | |
5590ff0d | 173 | int error = vfs_lstat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
174 | |
175 | if (!error) | |
176 | error = cp_old_stat(&stat, statbuf); | |
177 | ||
178 | return error; | |
179 | } | |
180 | asmlinkage long sys_fstat(unsigned int fd, struct __old_kernel_stat __user * statbuf) | |
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; | |
212 | tmp.st_mode = stat->mode; | |
213 | tmp.st_nlink = stat->nlink; | |
214 | if (tmp.st_nlink != stat->nlink) | |
215 | return -EOVERFLOW; | |
216 | SET_UID(tmp.st_uid, stat->uid); | |
217 | SET_GID(tmp.st_gid, stat->gid); | |
218 | #if BITS_PER_LONG == 32 | |
219 | tmp.st_rdev = old_encode_dev(stat->rdev); | |
220 | #else | |
221 | tmp.st_rdev = new_encode_dev(stat->rdev); | |
222 | #endif | |
223 | #if BITS_PER_LONG == 32 | |
224 | if (stat->size > MAX_NON_LFS) | |
225 | return -EOVERFLOW; | |
226 | #endif | |
227 | tmp.st_size = stat->size; | |
228 | tmp.st_atime = stat->atime.tv_sec; | |
229 | tmp.st_mtime = stat->mtime.tv_sec; | |
230 | tmp.st_ctime = stat->ctime.tv_sec; | |
231 | #ifdef STAT_HAVE_NSEC | |
232 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
233 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
234 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
235 | #endif | |
236 | tmp.st_blocks = stat->blocks; | |
237 | tmp.st_blksize = stat->blksize; | |
238 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
239 | } | |
240 | ||
5590ff0d UD |
241 | asmlinkage long sys_newstat(char __user *filename, struct stat __user *statbuf) |
242 | { | |
243 | struct kstat stat; | |
244 | int error = vfs_stat_fd(AT_FDCWD, filename, &stat); | |
245 | ||
246 | if (!error) | |
247 | error = cp_new_stat(&stat, statbuf); | |
248 | ||
249 | return error; | |
250 | } | |
251 | ||
252 | asmlinkage long sys_newlstat(char __user *filename, struct stat __user *statbuf) | |
1da177e4 LT |
253 | { |
254 | struct kstat stat; | |
5590ff0d | 255 | int error = vfs_lstat_fd(AT_FDCWD, filename, &stat); |
1da177e4 LT |
256 | |
257 | if (!error) | |
258 | error = cp_new_stat(&stat, statbuf); | |
259 | ||
260 | return error; | |
261 | } | |
5590ff0d | 262 | |
2833c28a | 263 | #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT) |
5590ff0d UD |
264 | asmlinkage long sys_newfstatat(int dfd, char __user *filename, |
265 | struct stat __user *statbuf, int flag) | |
1da177e4 LT |
266 | { |
267 | struct kstat stat; | |
5590ff0d UD |
268 | int error = -EINVAL; |
269 | ||
270 | if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) | |
271 | goto out; | |
272 | ||
273 | if (flag & AT_SYMLINK_NOFOLLOW) | |
274 | error = vfs_lstat_fd(dfd, filename, &stat); | |
275 | else | |
276 | error = vfs_stat_fd(dfd, filename, &stat); | |
1da177e4 LT |
277 | |
278 | if (!error) | |
279 | error = cp_new_stat(&stat, statbuf); | |
280 | ||
5590ff0d | 281 | out: |
1da177e4 LT |
282 | return error; |
283 | } | |
cff2b760 | 284 | #endif |
5590ff0d UD |
285 | |
286 | asmlinkage long sys_newfstat(unsigned int fd, struct stat __user *statbuf) | |
1da177e4 LT |
287 | { |
288 | struct kstat stat; | |
289 | int error = vfs_fstat(fd, &stat); | |
290 | ||
291 | if (!error) | |
292 | error = cp_new_stat(&stat, statbuf); | |
293 | ||
294 | return error; | |
295 | } | |
296 | ||
5590ff0d UD |
297 | asmlinkage long sys_readlinkat(int dfd, const char __user *path, |
298 | char __user *buf, int bufsiz) | |
1da177e4 LT |
299 | { |
300 | struct nameidata nd; | |
301 | int error; | |
302 | ||
303 | if (bufsiz <= 0) | |
304 | return -EINVAL; | |
305 | ||
5590ff0d | 306 | error = __user_walk_fd(dfd, path, 0, &nd); |
1da177e4 LT |
307 | if (!error) { |
308 | struct inode * inode = nd.dentry->d_inode; | |
309 | ||
310 | error = -EINVAL; | |
311 | if (inode->i_op && inode->i_op->readlink) { | |
312 | error = security_inode_readlink(nd.dentry); | |
313 | if (!error) { | |
314 | touch_atime(nd.mnt, nd.dentry); | |
315 | error = inode->i_op->readlink(nd.dentry, buf, bufsiz); | |
316 | } | |
317 | } | |
318 | path_release(&nd); | |
319 | } | |
320 | return error; | |
321 | } | |
322 | ||
5590ff0d UD |
323 | asmlinkage long sys_readlink(const char __user *path, char __user *buf, |
324 | int bufsiz) | |
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; | |
349 | #ifdef STAT64_HAS_BROKEN_ST_INO | |
350 | tmp.__st_ino = stat->ino; | |
351 | #endif | |
352 | tmp.st_mode = stat->mode; | |
353 | tmp.st_nlink = stat->nlink; | |
354 | tmp.st_uid = stat->uid; | |
355 | tmp.st_gid = stat->gid; | |
356 | tmp.st_atime = stat->atime.tv_sec; | |
357 | tmp.st_atime_nsec = stat->atime.tv_nsec; | |
358 | tmp.st_mtime = stat->mtime.tv_sec; | |
359 | tmp.st_mtime_nsec = stat->mtime.tv_nsec; | |
360 | tmp.st_ctime = stat->ctime.tv_sec; | |
361 | tmp.st_ctime_nsec = stat->ctime.tv_nsec; | |
362 | tmp.st_size = stat->size; | |
363 | tmp.st_blocks = stat->blocks; | |
364 | tmp.st_blksize = stat->blksize; | |
365 | return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; | |
366 | } | |
367 | ||
368 | asmlinkage long sys_stat64(char __user * filename, struct stat64 __user * statbuf) | |
369 | { | |
370 | struct kstat stat; | |
371 | int error = vfs_stat(filename, &stat); | |
372 | ||
373 | if (!error) | |
374 | error = cp_new_stat64(&stat, statbuf); | |
375 | ||
376 | return error; | |
377 | } | |
378 | asmlinkage long sys_lstat64(char __user * filename, struct stat64 __user * statbuf) | |
379 | { | |
380 | struct kstat stat; | |
381 | int error = vfs_lstat(filename, &stat); | |
382 | ||
383 | if (!error) | |
384 | error = cp_new_stat64(&stat, statbuf); | |
385 | ||
386 | return error; | |
387 | } | |
388 | asmlinkage long sys_fstat64(unsigned long fd, struct stat64 __user * statbuf) | |
389 | { | |
390 | struct kstat stat; | |
391 | int error = vfs_fstat(fd, &stat); | |
392 | ||
393 | if (!error) | |
394 | error = cp_new_stat64(&stat, statbuf); | |
395 | ||
396 | return error; | |
397 | } | |
398 | ||
cff2b760 UD |
399 | asmlinkage long sys_fstatat64(int dfd, char __user *filename, |
400 | struct stat64 __user *statbuf, int flag) | |
401 | { | |
402 | struct kstat stat; | |
403 | int error = -EINVAL; | |
404 | ||
405 | if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) | |
406 | goto out; | |
407 | ||
408 | if (flag & AT_SYMLINK_NOFOLLOW) | |
409 | error = vfs_lstat_fd(dfd, filename, &stat); | |
410 | else | |
411 | error = vfs_stat_fd(dfd, filename, &stat); | |
412 | ||
413 | if (!error) | |
414 | error = cp_new_stat64(&stat, statbuf); | |
415 | ||
416 | out: | |
417 | return error; | |
418 | } | |
1da177e4 LT |
419 | #endif /* __ARCH_WANT_STAT64 */ |
420 | ||
421 | void inode_add_bytes(struct inode *inode, loff_t bytes) | |
422 | { | |
423 | spin_lock(&inode->i_lock); | |
424 | inode->i_blocks += bytes >> 9; | |
425 | bytes &= 511; | |
426 | inode->i_bytes += bytes; | |
427 | if (inode->i_bytes >= 512) { | |
428 | inode->i_blocks++; | |
429 | inode->i_bytes -= 512; | |
430 | } | |
431 | spin_unlock(&inode->i_lock); | |
432 | } | |
433 | ||
434 | EXPORT_SYMBOL(inode_add_bytes); | |
435 | ||
436 | void inode_sub_bytes(struct inode *inode, loff_t bytes) | |
437 | { | |
438 | spin_lock(&inode->i_lock); | |
439 | inode->i_blocks -= bytes >> 9; | |
440 | bytes &= 511; | |
441 | if (inode->i_bytes < bytes) { | |
442 | inode->i_blocks--; | |
443 | inode->i_bytes += 512; | |
444 | } | |
445 | inode->i_bytes -= bytes; | |
446 | spin_unlock(&inode->i_lock); | |
447 | } | |
448 | ||
449 | EXPORT_SYMBOL(inode_sub_bytes); | |
450 | ||
451 | loff_t inode_get_bytes(struct inode *inode) | |
452 | { | |
453 | loff_t ret; | |
454 | ||
455 | spin_lock(&inode->i_lock); | |
456 | ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes; | |
457 | spin_unlock(&inode->i_lock); | |
458 | return ret; | |
459 | } | |
460 | ||
461 | EXPORT_SYMBOL(inode_get_bytes); | |
462 | ||
463 | void inode_set_bytes(struct inode *inode, loff_t bytes) | |
464 | { | |
465 | /* Caller is here responsible for sufficient locking | |
466 | * (ie. inode->i_lock) */ | |
467 | inode->i_blocks = bytes >> 9; | |
468 | inode->i_bytes = bytes & 511; | |
469 | } | |
470 | ||
471 | EXPORT_SYMBOL(inode_set_bytes); |