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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/read_write.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
7 | #include <linux/slab.h> | |
8 | #include <linux/stat.h> | |
9 | #include <linux/fcntl.h> | |
10 | #include <linux/file.h> | |
11 | #include <linux/uio.h> | |
0eeca283 | 12 | #include <linux/fsnotify.h> |
1da177e4 | 13 | #include <linux/security.h> |
630d9c47 | 14 | #include <linux/export.h> |
1da177e4 | 15 | #include <linux/syscalls.h> |
e28cc715 | 16 | #include <linux/pagemap.h> |
d6b29d7c | 17 | #include <linux/splice.h> |
561c6731 | 18 | #include <linux/compat.h> |
29732938 | 19 | #include <linux/mount.h> |
06ae43f3 | 20 | #include "internal.h" |
1da177e4 LT |
21 | |
22 | #include <asm/uaccess.h> | |
23 | #include <asm/unistd.h> | |
24 | ||
c0bd14af | 25 | typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *); |
293bc982 | 26 | typedef ssize_t (*iter_fn_t)(struct kiocb *, struct iov_iter *); |
c0bd14af | 27 | |
4b6f5d20 | 28 | const struct file_operations generic_ro_fops = { |
1da177e4 | 29 | .llseek = generic_file_llseek, |
aad4f8bb | 30 | .read_iter = generic_file_read_iter, |
1da177e4 | 31 | .mmap = generic_file_readonly_mmap, |
534f2aaa | 32 | .splice_read = generic_file_splice_read, |
1da177e4 LT |
33 | }; |
34 | ||
35 | EXPORT_SYMBOL(generic_ro_fops); | |
36 | ||
cccb5a1e | 37 | static inline int unsigned_offsets(struct file *file) |
4a3956c7 | 38 | { |
cccb5a1e | 39 | return file->f_mode & FMODE_UNSIGNED_OFFSET; |
4a3956c7 KH |
40 | } |
41 | ||
46a1c2c7 JL |
42 | /** |
43 | * vfs_setpos - update the file offset for lseek | |
44 | * @file: file structure in question | |
45 | * @offset: file offset to seek to | |
46 | * @maxsize: maximum file size | |
47 | * | |
48 | * This is a low-level filesystem helper for updating the file offset to | |
49 | * the value specified by @offset if the given offset is valid and it is | |
50 | * not equal to the current file offset. | |
51 | * | |
52 | * Return the specified offset on success and -EINVAL on invalid offset. | |
53 | */ | |
54 | loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize) | |
ef3d0fd2 AK |
55 | { |
56 | if (offset < 0 && !unsigned_offsets(file)) | |
57 | return -EINVAL; | |
58 | if (offset > maxsize) | |
59 | return -EINVAL; | |
60 | ||
61 | if (offset != file->f_pos) { | |
62 | file->f_pos = offset; | |
63 | file->f_version = 0; | |
64 | } | |
65 | return offset; | |
66 | } | |
46a1c2c7 | 67 | EXPORT_SYMBOL(vfs_setpos); |
ef3d0fd2 | 68 | |
3a8cff4f | 69 | /** |
5760495a | 70 | * generic_file_llseek_size - generic llseek implementation for regular files |
3a8cff4f CH |
71 | * @file: file structure to seek on |
72 | * @offset: file offset to seek to | |
965c8e59 | 73 | * @whence: type of seek |
e8b96eb5 ES |
74 | * @size: max size of this file in file system |
75 | * @eof: offset used for SEEK_END position | |
3a8cff4f | 76 | * |
5760495a | 77 | * This is a variant of generic_file_llseek that allows passing in a custom |
e8b96eb5 | 78 | * maximum file size and a custom EOF position, for e.g. hashed directories |
ef3d0fd2 AK |
79 | * |
80 | * Synchronization: | |
5760495a | 81 | * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms) |
ef3d0fd2 AK |
82 | * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes. |
83 | * read/writes behave like SEEK_SET against seeks. | |
3a8cff4f | 84 | */ |
9465efc9 | 85 | loff_t |
965c8e59 | 86 | generic_file_llseek_size(struct file *file, loff_t offset, int whence, |
e8b96eb5 | 87 | loff_t maxsize, loff_t eof) |
1da177e4 | 88 | { |
965c8e59 | 89 | switch (whence) { |
3a8cff4f | 90 | case SEEK_END: |
e8b96eb5 | 91 | offset += eof; |
3a8cff4f CH |
92 | break; |
93 | case SEEK_CUR: | |
5b6f1eb9 AK |
94 | /* |
95 | * Here we special-case the lseek(fd, 0, SEEK_CUR) | |
96 | * position-querying operation. Avoid rewriting the "same" | |
97 | * f_pos value back to the file because a concurrent read(), | |
98 | * write() or lseek() might have altered it | |
99 | */ | |
100 | if (offset == 0) | |
101 | return file->f_pos; | |
ef3d0fd2 AK |
102 | /* |
103 | * f_lock protects against read/modify/write race with other | |
104 | * SEEK_CURs. Note that parallel writes and reads behave | |
105 | * like SEEK_SET. | |
106 | */ | |
107 | spin_lock(&file->f_lock); | |
46a1c2c7 | 108 | offset = vfs_setpos(file, file->f_pos + offset, maxsize); |
ef3d0fd2 AK |
109 | spin_unlock(&file->f_lock); |
110 | return offset; | |
982d8165 JB |
111 | case SEEK_DATA: |
112 | /* | |
113 | * In the generic case the entire file is data, so as long as | |
114 | * offset isn't at the end of the file then the offset is data. | |
115 | */ | |
e8b96eb5 | 116 | if (offset >= eof) |
982d8165 JB |
117 | return -ENXIO; |
118 | break; | |
119 | case SEEK_HOLE: | |
120 | /* | |
121 | * There is a virtual hole at the end of the file, so as long as | |
122 | * offset isn't i_size or larger, return i_size. | |
123 | */ | |
e8b96eb5 | 124 | if (offset >= eof) |
982d8165 | 125 | return -ENXIO; |
e8b96eb5 | 126 | offset = eof; |
982d8165 | 127 | break; |
1da177e4 | 128 | } |
3a8cff4f | 129 | |
46a1c2c7 | 130 | return vfs_setpos(file, offset, maxsize); |
5760495a AK |
131 | } |
132 | EXPORT_SYMBOL(generic_file_llseek_size); | |
133 | ||
134 | /** | |
135 | * generic_file_llseek - generic llseek implementation for regular files | |
136 | * @file: file structure to seek on | |
137 | * @offset: file offset to seek to | |
965c8e59 | 138 | * @whence: type of seek |
5760495a AK |
139 | * |
140 | * This is a generic implemenation of ->llseek useable for all normal local | |
141 | * filesystems. It just updates the file offset to the value specified by | |
546ae2d2 | 142 | * @offset and @whence. |
5760495a | 143 | */ |
965c8e59 | 144 | loff_t generic_file_llseek(struct file *file, loff_t offset, int whence) |
5760495a AK |
145 | { |
146 | struct inode *inode = file->f_mapping->host; | |
147 | ||
965c8e59 | 148 | return generic_file_llseek_size(file, offset, whence, |
e8b96eb5 ES |
149 | inode->i_sb->s_maxbytes, |
150 | i_size_read(inode)); | |
1da177e4 | 151 | } |
9465efc9 | 152 | EXPORT_SYMBOL(generic_file_llseek); |
1da177e4 | 153 | |
1bf9d14d AV |
154 | /** |
155 | * fixed_size_llseek - llseek implementation for fixed-sized devices | |
156 | * @file: file structure to seek on | |
157 | * @offset: file offset to seek to | |
158 | * @whence: type of seek | |
159 | * @size: size of the file | |
160 | * | |
161 | */ | |
162 | loff_t fixed_size_llseek(struct file *file, loff_t offset, int whence, loff_t size) | |
163 | { | |
164 | switch (whence) { | |
165 | case SEEK_SET: case SEEK_CUR: case SEEK_END: | |
166 | return generic_file_llseek_size(file, offset, whence, | |
167 | size, size); | |
168 | default: | |
169 | return -EINVAL; | |
170 | } | |
171 | } | |
172 | EXPORT_SYMBOL(fixed_size_llseek); | |
173 | ||
b25472f9 AV |
174 | /** |
175 | * no_seek_end_llseek - llseek implementation for fixed-sized devices | |
176 | * @file: file structure to seek on | |
177 | * @offset: file offset to seek to | |
178 | * @whence: type of seek | |
179 | * | |
180 | */ | |
181 | loff_t no_seek_end_llseek(struct file *file, loff_t offset, int whence) | |
182 | { | |
183 | switch (whence) { | |
184 | case SEEK_SET: case SEEK_CUR: | |
185 | return generic_file_llseek_size(file, offset, whence, | |
186 | ~0ULL, 0); | |
187 | default: | |
188 | return -EINVAL; | |
189 | } | |
190 | } | |
191 | EXPORT_SYMBOL(no_seek_end_llseek); | |
192 | ||
193 | /** | |
194 | * no_seek_end_llseek_size - llseek implementation for fixed-sized devices | |
195 | * @file: file structure to seek on | |
196 | * @offset: file offset to seek to | |
197 | * @whence: type of seek | |
198 | * @size: maximal offset allowed | |
199 | * | |
200 | */ | |
201 | loff_t no_seek_end_llseek_size(struct file *file, loff_t offset, int whence, loff_t size) | |
202 | { | |
203 | switch (whence) { | |
204 | case SEEK_SET: case SEEK_CUR: | |
205 | return generic_file_llseek_size(file, offset, whence, | |
206 | size, 0); | |
207 | default: | |
208 | return -EINVAL; | |
209 | } | |
210 | } | |
211 | EXPORT_SYMBOL(no_seek_end_llseek_size); | |
212 | ||
ae6afc3f B |
213 | /** |
214 | * noop_llseek - No Operation Performed llseek implementation | |
215 | * @file: file structure to seek on | |
216 | * @offset: file offset to seek to | |
965c8e59 | 217 | * @whence: type of seek |
ae6afc3f B |
218 | * |
219 | * This is an implementation of ->llseek useable for the rare special case when | |
220 | * userspace expects the seek to succeed but the (device) file is actually not | |
221 | * able to perform the seek. In this case you use noop_llseek() instead of | |
222 | * falling back to the default implementation of ->llseek. | |
223 | */ | |
965c8e59 | 224 | loff_t noop_llseek(struct file *file, loff_t offset, int whence) |
ae6afc3f B |
225 | { |
226 | return file->f_pos; | |
227 | } | |
228 | EXPORT_SYMBOL(noop_llseek); | |
229 | ||
965c8e59 | 230 | loff_t no_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 LT |
231 | { |
232 | return -ESPIPE; | |
233 | } | |
234 | EXPORT_SYMBOL(no_llseek); | |
235 | ||
965c8e59 | 236 | loff_t default_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 | 237 | { |
496ad9aa | 238 | struct inode *inode = file_inode(file); |
16abef0e | 239 | loff_t retval; |
1da177e4 | 240 | |
5955102c | 241 | inode_lock(inode); |
965c8e59 | 242 | switch (whence) { |
7b8e8924 | 243 | case SEEK_END: |
982d8165 | 244 | offset += i_size_read(inode); |
1da177e4 | 245 | break; |
7b8e8924 | 246 | case SEEK_CUR: |
5b6f1eb9 AK |
247 | if (offset == 0) { |
248 | retval = file->f_pos; | |
249 | goto out; | |
250 | } | |
1da177e4 | 251 | offset += file->f_pos; |
982d8165 JB |
252 | break; |
253 | case SEEK_DATA: | |
254 | /* | |
255 | * In the generic case the entire file is data, so as | |
256 | * long as offset isn't at the end of the file then the | |
257 | * offset is data. | |
258 | */ | |
bacb2d81 DC |
259 | if (offset >= inode->i_size) { |
260 | retval = -ENXIO; | |
261 | goto out; | |
262 | } | |
982d8165 JB |
263 | break; |
264 | case SEEK_HOLE: | |
265 | /* | |
266 | * There is a virtual hole at the end of the file, so | |
267 | * as long as offset isn't i_size or larger, return | |
268 | * i_size. | |
269 | */ | |
bacb2d81 DC |
270 | if (offset >= inode->i_size) { |
271 | retval = -ENXIO; | |
272 | goto out; | |
273 | } | |
982d8165 JB |
274 | offset = inode->i_size; |
275 | break; | |
1da177e4 LT |
276 | } |
277 | retval = -EINVAL; | |
cccb5a1e | 278 | if (offset >= 0 || unsigned_offsets(file)) { |
1da177e4 LT |
279 | if (offset != file->f_pos) { |
280 | file->f_pos = offset; | |
281 | file->f_version = 0; | |
282 | } | |
283 | retval = offset; | |
284 | } | |
5b6f1eb9 | 285 | out: |
5955102c | 286 | inode_unlock(inode); |
1da177e4 LT |
287 | return retval; |
288 | } | |
289 | EXPORT_SYMBOL(default_llseek); | |
290 | ||
965c8e59 | 291 | loff_t vfs_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 LT |
292 | { |
293 | loff_t (*fn)(struct file *, loff_t, int); | |
294 | ||
295 | fn = no_llseek; | |
296 | if (file->f_mode & FMODE_LSEEK) { | |
72c2d531 | 297 | if (file->f_op->llseek) |
1da177e4 LT |
298 | fn = file->f_op->llseek; |
299 | } | |
965c8e59 | 300 | return fn(file, offset, whence); |
1da177e4 LT |
301 | } |
302 | EXPORT_SYMBOL(vfs_llseek); | |
303 | ||
9c225f26 LT |
304 | static inline struct fd fdget_pos(int fd) |
305 | { | |
bd2a31d5 | 306 | return __to_fd(__fdget_pos(fd)); |
9c225f26 LT |
307 | } |
308 | ||
309 | static inline void fdput_pos(struct fd f) | |
310 | { | |
311 | if (f.flags & FDPUT_POS_UNLOCK) | |
312 | mutex_unlock(&f.file->f_pos_lock); | |
313 | fdput(f); | |
314 | } | |
315 | ||
965c8e59 | 316 | SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence) |
1da177e4 LT |
317 | { |
318 | off_t retval; | |
9c225f26 | 319 | struct fd f = fdget_pos(fd); |
2903ff01 AV |
320 | if (!f.file) |
321 | return -EBADF; | |
1da177e4 LT |
322 | |
323 | retval = -EINVAL; | |
965c8e59 AM |
324 | if (whence <= SEEK_MAX) { |
325 | loff_t res = vfs_llseek(f.file, offset, whence); | |
1da177e4 LT |
326 | retval = res; |
327 | if (res != (loff_t)retval) | |
328 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ | |
329 | } | |
9c225f26 | 330 | fdput_pos(f); |
1da177e4 LT |
331 | return retval; |
332 | } | |
333 | ||
561c6731 AV |
334 | #ifdef CONFIG_COMPAT |
335 | COMPAT_SYSCALL_DEFINE3(lseek, unsigned int, fd, compat_off_t, offset, unsigned int, whence) | |
336 | { | |
337 | return sys_lseek(fd, offset, whence); | |
338 | } | |
339 | #endif | |
340 | ||
1da177e4 | 341 | #ifdef __ARCH_WANT_SYS_LLSEEK |
003d7ab4 HC |
342 | SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, |
343 | unsigned long, offset_low, loff_t __user *, result, | |
965c8e59 | 344 | unsigned int, whence) |
1da177e4 LT |
345 | { |
346 | int retval; | |
d7a15f8d | 347 | struct fd f = fdget_pos(fd); |
1da177e4 | 348 | loff_t offset; |
1da177e4 | 349 | |
2903ff01 AV |
350 | if (!f.file) |
351 | return -EBADF; | |
1da177e4 LT |
352 | |
353 | retval = -EINVAL; | |
965c8e59 | 354 | if (whence > SEEK_MAX) |
1da177e4 LT |
355 | goto out_putf; |
356 | ||
2903ff01 | 357 | offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low, |
965c8e59 | 358 | whence); |
1da177e4 LT |
359 | |
360 | retval = (int)offset; | |
361 | if (offset >= 0) { | |
362 | retval = -EFAULT; | |
363 | if (!copy_to_user(result, &offset, sizeof(offset))) | |
364 | retval = 0; | |
365 | } | |
366 | out_putf: | |
d7a15f8d | 367 | fdput_pos(f); |
1da177e4 LT |
368 | return retval; |
369 | } | |
370 | #endif | |
371 | ||
dbe4e192 CH |
372 | ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos) |
373 | { | |
374 | struct kiocb kiocb; | |
375 | ssize_t ret; | |
376 | ||
377 | if (!file->f_op->read_iter) | |
378 | return -EINVAL; | |
379 | ||
380 | init_sync_kiocb(&kiocb, file); | |
381 | kiocb.ki_pos = *ppos; | |
dbe4e192 CH |
382 | |
383 | iter->type |= READ; | |
384 | ret = file->f_op->read_iter(&kiocb, iter); | |
599bd19b | 385 | BUG_ON(ret == -EIOCBQUEUED); |
dbe4e192 CH |
386 | if (ret > 0) |
387 | *ppos = kiocb.ki_pos; | |
388 | return ret; | |
389 | } | |
390 | EXPORT_SYMBOL(vfs_iter_read); | |
391 | ||
392 | ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos) | |
393 | { | |
394 | struct kiocb kiocb; | |
395 | ssize_t ret; | |
396 | ||
397 | if (!file->f_op->write_iter) | |
398 | return -EINVAL; | |
399 | ||
400 | init_sync_kiocb(&kiocb, file); | |
401 | kiocb.ki_pos = *ppos; | |
dbe4e192 CH |
402 | |
403 | iter->type |= WRITE; | |
404 | ret = file->f_op->write_iter(&kiocb, iter); | |
599bd19b | 405 | BUG_ON(ret == -EIOCBQUEUED); |
dbe4e192 CH |
406 | if (ret > 0) |
407 | *ppos = kiocb.ki_pos; | |
408 | return ret; | |
409 | } | |
410 | EXPORT_SYMBOL(vfs_iter_write); | |
411 | ||
e28cc715 LT |
412 | /* |
413 | * rw_verify_area doesn't like huge counts. We limit | |
414 | * them to something that fits in "int" so that others | |
415 | * won't have to do range checks all the time. | |
416 | */ | |
68d70d03 | 417 | int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count) |
1da177e4 LT |
418 | { |
419 | struct inode *inode; | |
420 | loff_t pos; | |
c43e259c | 421 | int retval = -EINVAL; |
1da177e4 | 422 | |
496ad9aa | 423 | inode = file_inode(file); |
e28cc715 | 424 | if (unlikely((ssize_t) count < 0)) |
c43e259c | 425 | return retval; |
1da177e4 | 426 | pos = *ppos; |
cccb5a1e AV |
427 | if (unlikely(pos < 0)) { |
428 | if (!unsigned_offsets(file)) | |
429 | return retval; | |
430 | if (count >= -pos) /* both values are in 0..LLONG_MAX */ | |
431 | return -EOVERFLOW; | |
432 | } else if (unlikely((loff_t) (pos + count) < 0)) { | |
433 | if (!unsigned_offsets(file)) | |
4a3956c7 KH |
434 | return retval; |
435 | } | |
1da177e4 | 436 | |
bd61e0a9 | 437 | if (unlikely(inode->i_flctx && mandatory_lock(inode))) { |
acc15575 CH |
438 | retval = locks_mandatory_area(inode, file, pos, pos + count - 1, |
439 | read_write == READ ? F_RDLCK : F_WRLCK); | |
e28cc715 LT |
440 | if (retval < 0) |
441 | return retval; | |
442 | } | |
c43e259c JM |
443 | retval = security_file_permission(file, |
444 | read_write == READ ? MAY_READ : MAY_WRITE); | |
445 | if (retval) | |
446 | return retval; | |
e28cc715 | 447 | return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; |
1da177e4 LT |
448 | } |
449 | ||
5d5d5689 | 450 | static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
293bc982 AV |
451 | { |
452 | struct iovec iov = { .iov_base = buf, .iov_len = len }; | |
453 | struct kiocb kiocb; | |
454 | struct iov_iter iter; | |
455 | ssize_t ret; | |
456 | ||
457 | init_sync_kiocb(&kiocb, filp); | |
458 | kiocb.ki_pos = *ppos; | |
293bc982 AV |
459 | iov_iter_init(&iter, READ, &iov, 1, len); |
460 | ||
461 | ret = filp->f_op->read_iter(&kiocb, &iter); | |
599bd19b | 462 | BUG_ON(ret == -EIOCBQUEUED); |
293bc982 AV |
463 | *ppos = kiocb.ki_pos; |
464 | return ret; | |
465 | } | |
466 | ||
6fb5032e DK |
467 | ssize_t __vfs_read(struct file *file, char __user *buf, size_t count, |
468 | loff_t *pos) | |
469 | { | |
6fb5032e | 470 | if (file->f_op->read) |
3d04c8a1 | 471 | return file->f_op->read(file, buf, count, pos); |
6fb5032e | 472 | else if (file->f_op->read_iter) |
3d04c8a1 | 473 | return new_sync_read(file, buf, count, pos); |
6fb5032e | 474 | else |
3d04c8a1 | 475 | return -EINVAL; |
6fb5032e | 476 | } |
3d04c8a1 | 477 | EXPORT_SYMBOL(__vfs_read); |
6fb5032e | 478 | |
1da177e4 LT |
479 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) |
480 | { | |
481 | ssize_t ret; | |
482 | ||
483 | if (!(file->f_mode & FMODE_READ)) | |
484 | return -EBADF; | |
7f7f25e8 | 485 | if (!(file->f_mode & FMODE_CAN_READ)) |
1da177e4 LT |
486 | return -EINVAL; |
487 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) | |
488 | return -EFAULT; | |
489 | ||
490 | ret = rw_verify_area(READ, file, pos, count); | |
e28cc715 LT |
491 | if (ret >= 0) { |
492 | count = ret; | |
6fb5032e | 493 | ret = __vfs_read(file, buf, count, pos); |
c43e259c | 494 | if (ret > 0) { |
2a12a9d7 | 495 | fsnotify_access(file); |
c43e259c | 496 | add_rchar(current, ret); |
1da177e4 | 497 | } |
c43e259c | 498 | inc_syscr(current); |
1da177e4 LT |
499 | } |
500 | ||
501 | return ret; | |
502 | } | |
503 | ||
504 | EXPORT_SYMBOL(vfs_read); | |
505 | ||
5d5d5689 | 506 | static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) |
293bc982 AV |
507 | { |
508 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; | |
509 | struct kiocb kiocb; | |
510 | struct iov_iter iter; | |
511 | ssize_t ret; | |
512 | ||
513 | init_sync_kiocb(&kiocb, filp); | |
514 | kiocb.ki_pos = *ppos; | |
293bc982 AV |
515 | iov_iter_init(&iter, WRITE, &iov, 1, len); |
516 | ||
517 | ret = filp->f_op->write_iter(&kiocb, &iter); | |
599bd19b | 518 | BUG_ON(ret == -EIOCBQUEUED); |
f765b134 AV |
519 | if (ret > 0) |
520 | *ppos = kiocb.ki_pos; | |
293bc982 AV |
521 | return ret; |
522 | } | |
523 | ||
493c84c0 AV |
524 | ssize_t __vfs_write(struct file *file, const char __user *p, size_t count, |
525 | loff_t *pos) | |
526 | { | |
527 | if (file->f_op->write) | |
528 | return file->f_op->write(file, p, count, pos); | |
493c84c0 AV |
529 | else if (file->f_op->write_iter) |
530 | return new_sync_write(file, p, count, pos); | |
531 | else | |
532 | return -EINVAL; | |
533 | } | |
534 | EXPORT_SYMBOL(__vfs_write); | |
535 | ||
06ae43f3 AV |
536 | ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos) |
537 | { | |
538 | mm_segment_t old_fs; | |
539 | const char __user *p; | |
540 | ssize_t ret; | |
541 | ||
7f7f25e8 | 542 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
3e84f48e AV |
543 | return -EINVAL; |
544 | ||
06ae43f3 AV |
545 | old_fs = get_fs(); |
546 | set_fs(get_ds()); | |
547 | p = (__force const char __user *)buf; | |
548 | if (count > MAX_RW_COUNT) | |
549 | count = MAX_RW_COUNT; | |
493c84c0 | 550 | ret = __vfs_write(file, p, count, pos); |
06ae43f3 AV |
551 | set_fs(old_fs); |
552 | if (ret > 0) { | |
553 | fsnotify_modify(file); | |
554 | add_wchar(current, ret); | |
555 | } | |
556 | inc_syscw(current); | |
557 | return ret; | |
558 | } | |
559 | ||
2ec3a12a AV |
560 | EXPORT_SYMBOL(__kernel_write); |
561 | ||
1da177e4 LT |
562 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
563 | { | |
564 | ssize_t ret; | |
565 | ||
566 | if (!(file->f_mode & FMODE_WRITE)) | |
567 | return -EBADF; | |
7f7f25e8 | 568 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
1da177e4 LT |
569 | return -EINVAL; |
570 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) | |
571 | return -EFAULT; | |
572 | ||
573 | ret = rw_verify_area(WRITE, file, pos, count); | |
e28cc715 LT |
574 | if (ret >= 0) { |
575 | count = ret; | |
03d95eb2 | 576 | file_start_write(file); |
493c84c0 | 577 | ret = __vfs_write(file, buf, count, pos); |
c43e259c | 578 | if (ret > 0) { |
2a12a9d7 | 579 | fsnotify_modify(file); |
c43e259c | 580 | add_wchar(current, ret); |
1da177e4 | 581 | } |
c43e259c | 582 | inc_syscw(current); |
03d95eb2 | 583 | file_end_write(file); |
1da177e4 LT |
584 | } |
585 | ||
586 | return ret; | |
587 | } | |
588 | ||
589 | EXPORT_SYMBOL(vfs_write); | |
590 | ||
591 | static inline loff_t file_pos_read(struct file *file) | |
592 | { | |
593 | return file->f_pos; | |
594 | } | |
595 | ||
596 | static inline void file_pos_write(struct file *file, loff_t pos) | |
597 | { | |
598 | file->f_pos = pos; | |
599 | } | |
600 | ||
3cdad428 | 601 | SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) |
1da177e4 | 602 | { |
9c225f26 | 603 | struct fd f = fdget_pos(fd); |
1da177e4 | 604 | ssize_t ret = -EBADF; |
1da177e4 | 605 | |
2903ff01 AV |
606 | if (f.file) { |
607 | loff_t pos = file_pos_read(f.file); | |
608 | ret = vfs_read(f.file, buf, count, &pos); | |
5faf153e AV |
609 | if (ret >= 0) |
610 | file_pos_write(f.file, pos); | |
9c225f26 | 611 | fdput_pos(f); |
1da177e4 | 612 | } |
1da177e4 LT |
613 | return ret; |
614 | } | |
1da177e4 | 615 | |
3cdad428 HC |
616 | SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, |
617 | size_t, count) | |
1da177e4 | 618 | { |
9c225f26 | 619 | struct fd f = fdget_pos(fd); |
1da177e4 | 620 | ssize_t ret = -EBADF; |
1da177e4 | 621 | |
2903ff01 AV |
622 | if (f.file) { |
623 | loff_t pos = file_pos_read(f.file); | |
624 | ret = vfs_write(f.file, buf, count, &pos); | |
5faf153e AV |
625 | if (ret >= 0) |
626 | file_pos_write(f.file, pos); | |
9c225f26 | 627 | fdput_pos(f); |
1da177e4 LT |
628 | } |
629 | ||
630 | return ret; | |
631 | } | |
632 | ||
4a0fd5bf AV |
633 | SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, |
634 | size_t, count, loff_t, pos) | |
1da177e4 | 635 | { |
2903ff01 | 636 | struct fd f; |
1da177e4 | 637 | ssize_t ret = -EBADF; |
1da177e4 LT |
638 | |
639 | if (pos < 0) | |
640 | return -EINVAL; | |
641 | ||
2903ff01 AV |
642 | f = fdget(fd); |
643 | if (f.file) { | |
1da177e4 | 644 | ret = -ESPIPE; |
2903ff01 AV |
645 | if (f.file->f_mode & FMODE_PREAD) |
646 | ret = vfs_read(f.file, buf, count, &pos); | |
647 | fdput(f); | |
1da177e4 LT |
648 | } |
649 | ||
650 | return ret; | |
651 | } | |
652 | ||
4a0fd5bf AV |
653 | SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, |
654 | size_t, count, loff_t, pos) | |
1da177e4 | 655 | { |
2903ff01 | 656 | struct fd f; |
1da177e4 | 657 | ssize_t ret = -EBADF; |
1da177e4 LT |
658 | |
659 | if (pos < 0) | |
660 | return -EINVAL; | |
661 | ||
2903ff01 AV |
662 | f = fdget(fd); |
663 | if (f.file) { | |
1da177e4 | 664 | ret = -ESPIPE; |
2903ff01 AV |
665 | if (f.file->f_mode & FMODE_PWRITE) |
666 | ret = vfs_write(f.file, buf, count, &pos); | |
667 | fdput(f); | |
1da177e4 LT |
668 | } |
669 | ||
670 | return ret; | |
671 | } | |
672 | ||
673 | /* | |
674 | * Reduce an iovec's length in-place. Return the resulting number of segments | |
675 | */ | |
676 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) | |
677 | { | |
678 | unsigned long seg = 0; | |
679 | size_t len = 0; | |
680 | ||
681 | while (seg < nr_segs) { | |
682 | seg++; | |
683 | if (len + iov->iov_len >= to) { | |
684 | iov->iov_len = to - len; | |
685 | break; | |
686 | } | |
687 | len += iov->iov_len; | |
688 | iov++; | |
689 | } | |
690 | return seg; | |
691 | } | |
19295529 | 692 | EXPORT_SYMBOL(iov_shorten); |
1da177e4 | 693 | |
ac15ac06 | 694 | static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, |
793b80ef | 695 | loff_t *ppos, iter_fn_t fn, int flags) |
293bc982 AV |
696 | { |
697 | struct kiocb kiocb; | |
293bc982 AV |
698 | ssize_t ret; |
699 | ||
793b80ef CH |
700 | if (flags) |
701 | return -EOPNOTSUPP; | |
702 | ||
293bc982 AV |
703 | init_sync_kiocb(&kiocb, filp); |
704 | kiocb.ki_pos = *ppos; | |
293bc982 | 705 | |
ac15ac06 | 706 | ret = fn(&kiocb, iter); |
599bd19b | 707 | BUG_ON(ret == -EIOCBQUEUED); |
293bc982 AV |
708 | *ppos = kiocb.ki_pos; |
709 | return ret; | |
710 | } | |
711 | ||
ee0b3e67 | 712 | /* Do it by hand, with file-ops */ |
ac15ac06 | 713 | static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, |
793b80ef | 714 | loff_t *ppos, io_fn_t fn, int flags) |
ee0b3e67 | 715 | { |
ee0b3e67 BP |
716 | ssize_t ret = 0; |
717 | ||
793b80ef CH |
718 | if (flags) |
719 | return -EOPNOTSUPP; | |
720 | ||
ac15ac06 AV |
721 | while (iov_iter_count(iter)) { |
722 | struct iovec iovec = iov_iter_iovec(iter); | |
ee0b3e67 BP |
723 | ssize_t nr; |
724 | ||
ac15ac06 | 725 | nr = fn(filp, iovec.iov_base, iovec.iov_len, ppos); |
ee0b3e67 BP |
726 | |
727 | if (nr < 0) { | |
728 | if (!ret) | |
729 | ret = nr; | |
730 | break; | |
731 | } | |
732 | ret += nr; | |
ac15ac06 | 733 | if (nr != iovec.iov_len) |
ee0b3e67 | 734 | break; |
ac15ac06 | 735 | iov_iter_advance(iter, nr); |
ee0b3e67 BP |
736 | } |
737 | ||
738 | return ret; | |
739 | } | |
740 | ||
1da177e4 LT |
741 | /* A write operation does a read from user space and vice versa */ |
742 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) | |
743 | ||
eed4e51f BP |
744 | ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, |
745 | unsigned long nr_segs, unsigned long fast_segs, | |
746 | struct iovec *fast_pointer, | |
ac34ebb3 | 747 | struct iovec **ret_pointer) |
435f49a5 | 748 | { |
eed4e51f | 749 | unsigned long seg; |
435f49a5 | 750 | ssize_t ret; |
eed4e51f BP |
751 | struct iovec *iov = fast_pointer; |
752 | ||
435f49a5 LT |
753 | /* |
754 | * SuS says "The readv() function *may* fail if the iovcnt argument | |
755 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has | |
756 | * traditionally returned zero for zero segments, so... | |
757 | */ | |
eed4e51f BP |
758 | if (nr_segs == 0) { |
759 | ret = 0; | |
435f49a5 | 760 | goto out; |
eed4e51f BP |
761 | } |
762 | ||
435f49a5 LT |
763 | /* |
764 | * First get the "struct iovec" from user memory and | |
765 | * verify all the pointers | |
766 | */ | |
eed4e51f BP |
767 | if (nr_segs > UIO_MAXIOV) { |
768 | ret = -EINVAL; | |
435f49a5 | 769 | goto out; |
eed4e51f BP |
770 | } |
771 | if (nr_segs > fast_segs) { | |
435f49a5 | 772 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); |
eed4e51f BP |
773 | if (iov == NULL) { |
774 | ret = -ENOMEM; | |
435f49a5 | 775 | goto out; |
eed4e51f | 776 | } |
435f49a5 | 777 | } |
eed4e51f BP |
778 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { |
779 | ret = -EFAULT; | |
435f49a5 | 780 | goto out; |
eed4e51f BP |
781 | } |
782 | ||
435f49a5 | 783 | /* |
eed4e51f BP |
784 | * According to the Single Unix Specification we should return EINVAL |
785 | * if an element length is < 0 when cast to ssize_t or if the | |
786 | * total length would overflow the ssize_t return value of the | |
787 | * system call. | |
435f49a5 LT |
788 | * |
789 | * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the | |
790 | * overflow case. | |
791 | */ | |
eed4e51f | 792 | ret = 0; |
435f49a5 LT |
793 | for (seg = 0; seg < nr_segs; seg++) { |
794 | void __user *buf = iov[seg].iov_base; | |
795 | ssize_t len = (ssize_t)iov[seg].iov_len; | |
eed4e51f BP |
796 | |
797 | /* see if we we're about to use an invalid len or if | |
798 | * it's about to overflow ssize_t */ | |
435f49a5 | 799 | if (len < 0) { |
eed4e51f | 800 | ret = -EINVAL; |
435f49a5 | 801 | goto out; |
eed4e51f | 802 | } |
ac34ebb3 | 803 | if (type >= 0 |
fcf63409 | 804 | && unlikely(!access_ok(vrfy_dir(type), buf, len))) { |
eed4e51f | 805 | ret = -EFAULT; |
435f49a5 LT |
806 | goto out; |
807 | } | |
808 | if (len > MAX_RW_COUNT - ret) { | |
809 | len = MAX_RW_COUNT - ret; | |
810 | iov[seg].iov_len = len; | |
eed4e51f | 811 | } |
eed4e51f | 812 | ret += len; |
435f49a5 | 813 | } |
eed4e51f BP |
814 | out: |
815 | *ret_pointer = iov; | |
816 | return ret; | |
817 | } | |
818 | ||
1da177e4 LT |
819 | static ssize_t do_readv_writev(int type, struct file *file, |
820 | const struct iovec __user * uvector, | |
793b80ef CH |
821 | unsigned long nr_segs, loff_t *pos, |
822 | int flags) | |
1da177e4 | 823 | { |
1da177e4 LT |
824 | size_t tot_len; |
825 | struct iovec iovstack[UIO_FASTIOV]; | |
ee0b3e67 | 826 | struct iovec *iov = iovstack; |
ac15ac06 | 827 | struct iov_iter iter; |
1da177e4 | 828 | ssize_t ret; |
1da177e4 | 829 | io_fn_t fn; |
293bc982 | 830 | iter_fn_t iter_fn; |
1da177e4 | 831 | |
0504c074 AV |
832 | ret = import_iovec(type, uvector, nr_segs, |
833 | ARRAY_SIZE(iovstack), &iov, &iter); | |
834 | if (ret < 0) | |
835 | return ret; | |
1da177e4 | 836 | |
0504c074 AV |
837 | tot_len = iov_iter_count(&iter); |
838 | if (!tot_len) | |
839 | goto out; | |
1da177e4 | 840 | ret = rw_verify_area(type, file, pos, tot_len); |
e28cc715 | 841 | if (ret < 0) |
411b67b4 | 842 | goto out; |
1da177e4 | 843 | |
1da177e4 LT |
844 | if (type == READ) { |
845 | fn = file->f_op->read; | |
293bc982 | 846 | iter_fn = file->f_op->read_iter; |
1da177e4 LT |
847 | } else { |
848 | fn = (io_fn_t)file->f_op->write; | |
293bc982 | 849 | iter_fn = file->f_op->write_iter; |
03d95eb2 | 850 | file_start_write(file); |
1da177e4 LT |
851 | } |
852 | ||
293bc982 | 853 | if (iter_fn) |
793b80ef | 854 | ret = do_iter_readv_writev(file, &iter, pos, iter_fn, flags); |
ee0b3e67 | 855 | else |
793b80ef | 856 | ret = do_loop_readv_writev(file, &iter, pos, fn, flags); |
1da177e4 | 857 | |
03d95eb2 AV |
858 | if (type != READ) |
859 | file_end_write(file); | |
860 | ||
1da177e4 | 861 | out: |
0504c074 | 862 | kfree(iov); |
0eeca283 RL |
863 | if ((ret + (type == READ)) > 0) { |
864 | if (type == READ) | |
2a12a9d7 | 865 | fsnotify_access(file); |
0eeca283 | 866 | else |
2a12a9d7 | 867 | fsnotify_modify(file); |
0eeca283 | 868 | } |
1da177e4 | 869 | return ret; |
1da177e4 LT |
870 | } |
871 | ||
872 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, | |
793b80ef | 873 | unsigned long vlen, loff_t *pos, int flags) |
1da177e4 LT |
874 | { |
875 | if (!(file->f_mode & FMODE_READ)) | |
876 | return -EBADF; | |
7f7f25e8 | 877 | if (!(file->f_mode & FMODE_CAN_READ)) |
1da177e4 LT |
878 | return -EINVAL; |
879 | ||
793b80ef | 880 | return do_readv_writev(READ, file, vec, vlen, pos, flags); |
1da177e4 LT |
881 | } |
882 | ||
883 | EXPORT_SYMBOL(vfs_readv); | |
884 | ||
885 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, | |
793b80ef | 886 | unsigned long vlen, loff_t *pos, int flags) |
1da177e4 LT |
887 | { |
888 | if (!(file->f_mode & FMODE_WRITE)) | |
889 | return -EBADF; | |
7f7f25e8 | 890 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
1da177e4 LT |
891 | return -EINVAL; |
892 | ||
793b80ef | 893 | return do_readv_writev(WRITE, file, vec, vlen, pos, flags); |
1da177e4 LT |
894 | } |
895 | ||
896 | EXPORT_SYMBOL(vfs_writev); | |
897 | ||
3cdad428 HC |
898 | SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, |
899 | unsigned long, vlen) | |
1da177e4 | 900 | { |
9c225f26 | 901 | struct fd f = fdget_pos(fd); |
1da177e4 | 902 | ssize_t ret = -EBADF; |
1da177e4 | 903 | |
2903ff01 AV |
904 | if (f.file) { |
905 | loff_t pos = file_pos_read(f.file); | |
793b80ef | 906 | ret = vfs_readv(f.file, vec, vlen, &pos, 0); |
5faf153e AV |
907 | if (ret >= 0) |
908 | file_pos_write(f.file, pos); | |
9c225f26 | 909 | fdput_pos(f); |
1da177e4 LT |
910 | } |
911 | ||
912 | if (ret > 0) | |
4b98d11b AD |
913 | add_rchar(current, ret); |
914 | inc_syscr(current); | |
1da177e4 LT |
915 | return ret; |
916 | } | |
917 | ||
3cdad428 HC |
918 | SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, |
919 | unsigned long, vlen) | |
1da177e4 | 920 | { |
9c225f26 | 921 | struct fd f = fdget_pos(fd); |
1da177e4 | 922 | ssize_t ret = -EBADF; |
1da177e4 | 923 | |
2903ff01 AV |
924 | if (f.file) { |
925 | loff_t pos = file_pos_read(f.file); | |
793b80ef | 926 | ret = vfs_writev(f.file, vec, vlen, &pos, 0); |
5faf153e AV |
927 | if (ret >= 0) |
928 | file_pos_write(f.file, pos); | |
9c225f26 | 929 | fdput_pos(f); |
1da177e4 LT |
930 | } |
931 | ||
932 | if (ret > 0) | |
4b98d11b AD |
933 | add_wchar(current, ret); |
934 | inc_syscw(current); | |
1da177e4 LT |
935 | return ret; |
936 | } | |
937 | ||
601cc11d LT |
938 | static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) |
939 | { | |
940 | #define HALF_LONG_BITS (BITS_PER_LONG / 2) | |
941 | return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; | |
942 | } | |
943 | ||
f3554f4b | 944 | SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, |
601cc11d | 945 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
f3554f4b | 946 | { |
601cc11d | 947 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
2903ff01 | 948 | struct fd f; |
f3554f4b | 949 | ssize_t ret = -EBADF; |
f3554f4b GH |
950 | |
951 | if (pos < 0) | |
952 | return -EINVAL; | |
953 | ||
2903ff01 AV |
954 | f = fdget(fd); |
955 | if (f.file) { | |
f3554f4b | 956 | ret = -ESPIPE; |
2903ff01 | 957 | if (f.file->f_mode & FMODE_PREAD) |
793b80ef | 958 | ret = vfs_readv(f.file, vec, vlen, &pos, 0); |
2903ff01 | 959 | fdput(f); |
f3554f4b GH |
960 | } |
961 | ||
962 | if (ret > 0) | |
963 | add_rchar(current, ret); | |
964 | inc_syscr(current); | |
965 | return ret; | |
966 | } | |
967 | ||
968 | SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, | |
601cc11d | 969 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
f3554f4b | 970 | { |
601cc11d | 971 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
2903ff01 | 972 | struct fd f; |
f3554f4b | 973 | ssize_t ret = -EBADF; |
f3554f4b GH |
974 | |
975 | if (pos < 0) | |
976 | return -EINVAL; | |
977 | ||
2903ff01 AV |
978 | f = fdget(fd); |
979 | if (f.file) { | |
f3554f4b | 980 | ret = -ESPIPE; |
2903ff01 | 981 | if (f.file->f_mode & FMODE_PWRITE) |
793b80ef | 982 | ret = vfs_writev(f.file, vec, vlen, &pos, 0); |
2903ff01 | 983 | fdput(f); |
f3554f4b GH |
984 | } |
985 | ||
986 | if (ret > 0) | |
987 | add_wchar(current, ret); | |
988 | inc_syscw(current); | |
989 | return ret; | |
990 | } | |
991 | ||
72ec3516 AV |
992 | #ifdef CONFIG_COMPAT |
993 | ||
994 | static ssize_t compat_do_readv_writev(int type, struct file *file, | |
995 | const struct compat_iovec __user *uvector, | |
793b80ef CH |
996 | unsigned long nr_segs, loff_t *pos, |
997 | int flags) | |
72ec3516 AV |
998 | { |
999 | compat_ssize_t tot_len; | |
1000 | struct iovec iovstack[UIO_FASTIOV]; | |
1001 | struct iovec *iov = iovstack; | |
ac15ac06 | 1002 | struct iov_iter iter; |
72ec3516 AV |
1003 | ssize_t ret; |
1004 | io_fn_t fn; | |
293bc982 | 1005 | iter_fn_t iter_fn; |
72ec3516 | 1006 | |
0504c074 AV |
1007 | ret = compat_import_iovec(type, uvector, nr_segs, |
1008 | UIO_FASTIOV, &iov, &iter); | |
1009 | if (ret < 0) | |
1010 | return ret; | |
72ec3516 | 1011 | |
0504c074 AV |
1012 | tot_len = iov_iter_count(&iter); |
1013 | if (!tot_len) | |
1014 | goto out; | |
72ec3516 AV |
1015 | ret = rw_verify_area(type, file, pos, tot_len); |
1016 | if (ret < 0) | |
1017 | goto out; | |
1018 | ||
72ec3516 AV |
1019 | if (type == READ) { |
1020 | fn = file->f_op->read; | |
293bc982 | 1021 | iter_fn = file->f_op->read_iter; |
72ec3516 AV |
1022 | } else { |
1023 | fn = (io_fn_t)file->f_op->write; | |
293bc982 | 1024 | iter_fn = file->f_op->write_iter; |
03d95eb2 | 1025 | file_start_write(file); |
72ec3516 AV |
1026 | } |
1027 | ||
293bc982 | 1028 | if (iter_fn) |
793b80ef | 1029 | ret = do_iter_readv_writev(file, &iter, pos, iter_fn, flags); |
03d95eb2 | 1030 | else |
793b80ef | 1031 | ret = do_loop_readv_writev(file, &iter, pos, fn, flags); |
72ec3516 | 1032 | |
03d95eb2 AV |
1033 | if (type != READ) |
1034 | file_end_write(file); | |
1035 | ||
72ec3516 | 1036 | out: |
0504c074 | 1037 | kfree(iov); |
72ec3516 AV |
1038 | if ((ret + (type == READ)) > 0) { |
1039 | if (type == READ) | |
1040 | fsnotify_access(file); | |
1041 | else | |
1042 | fsnotify_modify(file); | |
1043 | } | |
1044 | return ret; | |
1045 | } | |
1046 | ||
1047 | static size_t compat_readv(struct file *file, | |
1048 | const struct compat_iovec __user *vec, | |
1049 | unsigned long vlen, loff_t *pos) | |
1050 | { | |
1051 | ssize_t ret = -EBADF; | |
1052 | ||
1053 | if (!(file->f_mode & FMODE_READ)) | |
1054 | goto out; | |
1055 | ||
1056 | ret = -EINVAL; | |
7f7f25e8 | 1057 | if (!(file->f_mode & FMODE_CAN_READ)) |
72ec3516 AV |
1058 | goto out; |
1059 | ||
793b80ef | 1060 | ret = compat_do_readv_writev(READ, file, vec, vlen, pos, 0); |
72ec3516 AV |
1061 | |
1062 | out: | |
1063 | if (ret > 0) | |
1064 | add_rchar(current, ret); | |
1065 | inc_syscr(current); | |
1066 | return ret; | |
1067 | } | |
1068 | ||
dfd948e3 | 1069 | COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, |
72ec3516 | 1070 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1071 | compat_ulong_t, vlen) |
72ec3516 | 1072 | { |
9c225f26 | 1073 | struct fd f = fdget_pos(fd); |
72ec3516 AV |
1074 | ssize_t ret; |
1075 | loff_t pos; | |
1076 | ||
1077 | if (!f.file) | |
1078 | return -EBADF; | |
1079 | pos = f.file->f_pos; | |
1080 | ret = compat_readv(f.file, vec, vlen, &pos); | |
5faf153e AV |
1081 | if (ret >= 0) |
1082 | f.file->f_pos = pos; | |
9c225f26 | 1083 | fdput_pos(f); |
72ec3516 AV |
1084 | return ret; |
1085 | } | |
1086 | ||
378a10f3 HC |
1087 | static long __compat_sys_preadv64(unsigned long fd, |
1088 | const struct compat_iovec __user *vec, | |
1089 | unsigned long vlen, loff_t pos) | |
72ec3516 AV |
1090 | { |
1091 | struct fd f; | |
1092 | ssize_t ret; | |
1093 | ||
1094 | if (pos < 0) | |
1095 | return -EINVAL; | |
1096 | f = fdget(fd); | |
1097 | if (!f.file) | |
1098 | return -EBADF; | |
1099 | ret = -ESPIPE; | |
1100 | if (f.file->f_mode & FMODE_PREAD) | |
1101 | ret = compat_readv(f.file, vec, vlen, &pos); | |
1102 | fdput(f); | |
1103 | return ret; | |
1104 | } | |
1105 | ||
378a10f3 HC |
1106 | #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64 |
1107 | COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, | |
1108 | const struct compat_iovec __user *,vec, | |
1109 | unsigned long, vlen, loff_t, pos) | |
1110 | { | |
1111 | return __compat_sys_preadv64(fd, vec, vlen, pos); | |
1112 | } | |
1113 | #endif | |
1114 | ||
dfd948e3 | 1115 | COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, |
72ec3516 | 1116 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1117 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1118 | { |
1119 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 HC |
1120 | |
1121 | return __compat_sys_preadv64(fd, vec, vlen, pos); | |
72ec3516 AV |
1122 | } |
1123 | ||
1124 | static size_t compat_writev(struct file *file, | |
1125 | const struct compat_iovec __user *vec, | |
1126 | unsigned long vlen, loff_t *pos) | |
1127 | { | |
1128 | ssize_t ret = -EBADF; | |
1129 | ||
1130 | if (!(file->f_mode & FMODE_WRITE)) | |
1131 | goto out; | |
1132 | ||
1133 | ret = -EINVAL; | |
7f7f25e8 | 1134 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
72ec3516 AV |
1135 | goto out; |
1136 | ||
793b80ef | 1137 | ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos, 0); |
72ec3516 AV |
1138 | |
1139 | out: | |
1140 | if (ret > 0) | |
1141 | add_wchar(current, ret); | |
1142 | inc_syscw(current); | |
1143 | return ret; | |
1144 | } | |
1145 | ||
dfd948e3 | 1146 | COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, |
72ec3516 | 1147 | const struct compat_iovec __user *, vec, |
dfd948e3 | 1148 | compat_ulong_t, vlen) |
72ec3516 | 1149 | { |
9c225f26 | 1150 | struct fd f = fdget_pos(fd); |
72ec3516 AV |
1151 | ssize_t ret; |
1152 | loff_t pos; | |
1153 | ||
1154 | if (!f.file) | |
1155 | return -EBADF; | |
1156 | pos = f.file->f_pos; | |
1157 | ret = compat_writev(f.file, vec, vlen, &pos); | |
5faf153e AV |
1158 | if (ret >= 0) |
1159 | f.file->f_pos = pos; | |
9c225f26 | 1160 | fdput_pos(f); |
72ec3516 AV |
1161 | return ret; |
1162 | } | |
1163 | ||
378a10f3 HC |
1164 | static long __compat_sys_pwritev64(unsigned long fd, |
1165 | const struct compat_iovec __user *vec, | |
1166 | unsigned long vlen, loff_t pos) | |
72ec3516 AV |
1167 | { |
1168 | struct fd f; | |
1169 | ssize_t ret; | |
1170 | ||
1171 | if (pos < 0) | |
1172 | return -EINVAL; | |
1173 | f = fdget(fd); | |
1174 | if (!f.file) | |
1175 | return -EBADF; | |
1176 | ret = -ESPIPE; | |
1177 | if (f.file->f_mode & FMODE_PWRITE) | |
1178 | ret = compat_writev(f.file, vec, vlen, &pos); | |
1179 | fdput(f); | |
1180 | return ret; | |
1181 | } | |
1182 | ||
378a10f3 HC |
1183 | #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64 |
1184 | COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, | |
1185 | const struct compat_iovec __user *,vec, | |
1186 | unsigned long, vlen, loff_t, pos) | |
1187 | { | |
1188 | return __compat_sys_pwritev64(fd, vec, vlen, pos); | |
1189 | } | |
1190 | #endif | |
1191 | ||
dfd948e3 | 1192 | COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, |
72ec3516 | 1193 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1194 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1195 | { |
1196 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 HC |
1197 | |
1198 | return __compat_sys_pwritev64(fd, vec, vlen, pos); | |
72ec3516 AV |
1199 | } |
1200 | #endif | |
1201 | ||
19f4fc3a AV |
1202 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, |
1203 | size_t count, loff_t max) | |
1da177e4 | 1204 | { |
2903ff01 AV |
1205 | struct fd in, out; |
1206 | struct inode *in_inode, *out_inode; | |
1da177e4 | 1207 | loff_t pos; |
7995bd28 | 1208 | loff_t out_pos; |
1da177e4 | 1209 | ssize_t retval; |
2903ff01 | 1210 | int fl; |
1da177e4 LT |
1211 | |
1212 | /* | |
1213 | * Get input file, and verify that it is ok.. | |
1214 | */ | |
1215 | retval = -EBADF; | |
2903ff01 AV |
1216 | in = fdget(in_fd); |
1217 | if (!in.file) | |
1da177e4 | 1218 | goto out; |
2903ff01 | 1219 | if (!(in.file->f_mode & FMODE_READ)) |
1da177e4 | 1220 | goto fput_in; |
1da177e4 | 1221 | retval = -ESPIPE; |
7995bd28 AV |
1222 | if (!ppos) { |
1223 | pos = in.file->f_pos; | |
1224 | } else { | |
1225 | pos = *ppos; | |
2903ff01 | 1226 | if (!(in.file->f_mode & FMODE_PREAD)) |
1da177e4 | 1227 | goto fput_in; |
7995bd28 AV |
1228 | } |
1229 | retval = rw_verify_area(READ, in.file, &pos, count); | |
e28cc715 | 1230 | if (retval < 0) |
1da177e4 | 1231 | goto fput_in; |
e28cc715 | 1232 | count = retval; |
1da177e4 | 1233 | |
1da177e4 LT |
1234 | /* |
1235 | * Get output file, and verify that it is ok.. | |
1236 | */ | |
1237 | retval = -EBADF; | |
2903ff01 AV |
1238 | out = fdget(out_fd); |
1239 | if (!out.file) | |
1da177e4 | 1240 | goto fput_in; |
2903ff01 | 1241 | if (!(out.file->f_mode & FMODE_WRITE)) |
1da177e4 LT |
1242 | goto fput_out; |
1243 | retval = -EINVAL; | |
496ad9aa AV |
1244 | in_inode = file_inode(in.file); |
1245 | out_inode = file_inode(out.file); | |
7995bd28 AV |
1246 | out_pos = out.file->f_pos; |
1247 | retval = rw_verify_area(WRITE, out.file, &out_pos, count); | |
e28cc715 | 1248 | if (retval < 0) |
1da177e4 | 1249 | goto fput_out; |
e28cc715 | 1250 | count = retval; |
1da177e4 | 1251 | |
1da177e4 LT |
1252 | if (!max) |
1253 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); | |
1254 | ||
1da177e4 LT |
1255 | if (unlikely(pos + count > max)) { |
1256 | retval = -EOVERFLOW; | |
1257 | if (pos >= max) | |
1258 | goto fput_out; | |
1259 | count = max - pos; | |
1260 | } | |
1261 | ||
d96e6e71 | 1262 | fl = 0; |
534f2aaa | 1263 | #if 0 |
d96e6e71 JA |
1264 | /* |
1265 | * We need to debate whether we can enable this or not. The | |
1266 | * man page documents EAGAIN return for the output at least, | |
1267 | * and the application is arguably buggy if it doesn't expect | |
1268 | * EAGAIN on a non-blocking file descriptor. | |
1269 | */ | |
2903ff01 | 1270 | if (in.file->f_flags & O_NONBLOCK) |
d96e6e71 | 1271 | fl = SPLICE_F_NONBLOCK; |
534f2aaa | 1272 | #endif |
50cd2c57 | 1273 | file_start_write(out.file); |
7995bd28 | 1274 | retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl); |
50cd2c57 | 1275 | file_end_write(out.file); |
1da177e4 LT |
1276 | |
1277 | if (retval > 0) { | |
4b98d11b AD |
1278 | add_rchar(current, retval); |
1279 | add_wchar(current, retval); | |
a68c2f12 SW |
1280 | fsnotify_access(in.file); |
1281 | fsnotify_modify(out.file); | |
7995bd28 AV |
1282 | out.file->f_pos = out_pos; |
1283 | if (ppos) | |
1284 | *ppos = pos; | |
1285 | else | |
1286 | in.file->f_pos = pos; | |
1da177e4 | 1287 | } |
1da177e4 | 1288 | |
4b98d11b AD |
1289 | inc_syscr(current); |
1290 | inc_syscw(current); | |
7995bd28 | 1291 | if (pos > max) |
1da177e4 LT |
1292 | retval = -EOVERFLOW; |
1293 | ||
1294 | fput_out: | |
2903ff01 | 1295 | fdput(out); |
1da177e4 | 1296 | fput_in: |
2903ff01 | 1297 | fdput(in); |
1da177e4 LT |
1298 | out: |
1299 | return retval; | |
1300 | } | |
1301 | ||
002c8976 | 1302 | SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count) |
1da177e4 LT |
1303 | { |
1304 | loff_t pos; | |
1305 | off_t off; | |
1306 | ssize_t ret; | |
1307 | ||
1308 | if (offset) { | |
1309 | if (unlikely(get_user(off, offset))) | |
1310 | return -EFAULT; | |
1311 | pos = off; | |
1312 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1313 | if (unlikely(put_user(pos, offset))) | |
1314 | return -EFAULT; | |
1315 | return ret; | |
1316 | } | |
1317 | ||
1318 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1319 | } | |
1320 | ||
002c8976 | 1321 | SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count) |
1da177e4 LT |
1322 | { |
1323 | loff_t pos; | |
1324 | ssize_t ret; | |
1325 | ||
1326 | if (offset) { | |
1327 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1328 | return -EFAULT; | |
1329 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1330 | if (unlikely(put_user(pos, offset))) | |
1331 | return -EFAULT; | |
1332 | return ret; | |
1333 | } | |
1334 | ||
1335 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1336 | } | |
19f4fc3a AV |
1337 | |
1338 | #ifdef CONFIG_COMPAT | |
1339 | COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, | |
1340 | compat_off_t __user *, offset, compat_size_t, count) | |
1341 | { | |
1342 | loff_t pos; | |
1343 | off_t off; | |
1344 | ssize_t ret; | |
1345 | ||
1346 | if (offset) { | |
1347 | if (unlikely(get_user(off, offset))) | |
1348 | return -EFAULT; | |
1349 | pos = off; | |
1350 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1351 | if (unlikely(put_user(pos, offset))) | |
1352 | return -EFAULT; | |
1353 | return ret; | |
1354 | } | |
1355 | ||
1356 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1357 | } | |
1358 | ||
1359 | COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, | |
1360 | compat_loff_t __user *, offset, compat_size_t, count) | |
1361 | { | |
1362 | loff_t pos; | |
1363 | ssize_t ret; | |
1364 | ||
1365 | if (offset) { | |
1366 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1367 | return -EFAULT; | |
1368 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1369 | if (unlikely(put_user(pos, offset))) | |
1370 | return -EFAULT; | |
1371 | return ret; | |
1372 | } | |
1373 | ||
1374 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1375 | } | |
1376 | #endif | |
29732938 ZB |
1377 | |
1378 | /* | |
1379 | * copy_file_range() differs from regular file read and write in that it | |
1380 | * specifically allows return partial success. When it does so is up to | |
1381 | * the copy_file_range method. | |
1382 | */ | |
1383 | ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, | |
1384 | struct file *file_out, loff_t pos_out, | |
1385 | size_t len, unsigned int flags) | |
1386 | { | |
1387 | struct inode *inode_in = file_inode(file_in); | |
1388 | struct inode *inode_out = file_inode(file_out); | |
1389 | ssize_t ret; | |
1390 | ||
1391 | if (flags != 0) | |
1392 | return -EINVAL; | |
1393 | ||
1394 | /* copy_file_range allows full ssize_t len, ignoring MAX_RW_COUNT */ | |
1395 | ret = rw_verify_area(READ, file_in, &pos_in, len); | |
1396 | if (ret >= 0) | |
1397 | ret = rw_verify_area(WRITE, file_out, &pos_out, len); | |
1398 | if (ret < 0) | |
1399 | return ret; | |
1400 | ||
1401 | if (!(file_in->f_mode & FMODE_READ) || | |
1402 | !(file_out->f_mode & FMODE_WRITE) || | |
eac70053 | 1403 | (file_out->f_flags & O_APPEND)) |
29732938 ZB |
1404 | return -EBADF; |
1405 | ||
1406 | /* this could be relaxed once a method supports cross-fs copies */ | |
1407 | if (inode_in->i_sb != inode_out->i_sb) | |
1408 | return -EXDEV; | |
1409 | ||
1410 | if (len == 0) | |
1411 | return 0; | |
1412 | ||
1413 | ret = mnt_want_write_file(file_out); | |
1414 | if (ret) | |
1415 | return ret; | |
1416 | ||
eac70053 AS |
1417 | ret = -EOPNOTSUPP; |
1418 | if (file_out->f_op->copy_file_range) | |
1419 | ret = file_out->f_op->copy_file_range(file_in, pos_in, file_out, | |
1420 | pos_out, len, flags); | |
1421 | if (ret == -EOPNOTSUPP) | |
1422 | ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out, | |
1423 | len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); | |
1424 | ||
29732938 ZB |
1425 | if (ret > 0) { |
1426 | fsnotify_access(file_in); | |
1427 | add_rchar(current, ret); | |
1428 | fsnotify_modify(file_out); | |
1429 | add_wchar(current, ret); | |
1430 | } | |
1431 | inc_syscr(current); | |
1432 | inc_syscw(current); | |
1433 | ||
1434 | mnt_drop_write_file(file_out); | |
1435 | ||
1436 | return ret; | |
1437 | } | |
1438 | EXPORT_SYMBOL(vfs_copy_file_range); | |
1439 | ||
1440 | SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in, | |
1441 | int, fd_out, loff_t __user *, off_out, | |
1442 | size_t, len, unsigned int, flags) | |
1443 | { | |
1444 | loff_t pos_in; | |
1445 | loff_t pos_out; | |
1446 | struct fd f_in; | |
1447 | struct fd f_out; | |
1448 | ssize_t ret = -EBADF; | |
1449 | ||
1450 | f_in = fdget(fd_in); | |
1451 | if (!f_in.file) | |
1452 | goto out2; | |
1453 | ||
1454 | f_out = fdget(fd_out); | |
1455 | if (!f_out.file) | |
1456 | goto out1; | |
1457 | ||
1458 | ret = -EFAULT; | |
1459 | if (off_in) { | |
1460 | if (copy_from_user(&pos_in, off_in, sizeof(loff_t))) | |
1461 | goto out; | |
1462 | } else { | |
1463 | pos_in = f_in.file->f_pos; | |
1464 | } | |
1465 | ||
1466 | if (off_out) { | |
1467 | if (copy_from_user(&pos_out, off_out, sizeof(loff_t))) | |
1468 | goto out; | |
1469 | } else { | |
1470 | pos_out = f_out.file->f_pos; | |
1471 | } | |
1472 | ||
1473 | ret = vfs_copy_file_range(f_in.file, pos_in, f_out.file, pos_out, len, | |
1474 | flags); | |
1475 | if (ret > 0) { | |
1476 | pos_in += ret; | |
1477 | pos_out += ret; | |
1478 | ||
1479 | if (off_in) { | |
1480 | if (copy_to_user(off_in, &pos_in, sizeof(loff_t))) | |
1481 | ret = -EFAULT; | |
1482 | } else { | |
1483 | f_in.file->f_pos = pos_in; | |
1484 | } | |
1485 | ||
1486 | if (off_out) { | |
1487 | if (copy_to_user(off_out, &pos_out, sizeof(loff_t))) | |
1488 | ret = -EFAULT; | |
1489 | } else { | |
1490 | f_out.file->f_pos = pos_out; | |
1491 | } | |
1492 | } | |
1493 | ||
1494 | out: | |
1495 | fdput(f_out); | |
1496 | out1: | |
1497 | fdput(f_in); | |
1498 | out2: | |
1499 | return ret; | |
1500 | } | |
04b38d60 CH |
1501 | |
1502 | static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write) | |
1503 | { | |
1504 | struct inode *inode = file_inode(file); | |
1505 | ||
1506 | if (unlikely(pos < 0)) | |
1507 | return -EINVAL; | |
1508 | ||
1509 | if (unlikely((loff_t) (pos + len) < 0)) | |
1510 | return -EINVAL; | |
1511 | ||
1512 | if (unlikely(inode->i_flctx && mandatory_lock(inode))) { | |
1513 | loff_t end = len ? pos + len - 1 : OFFSET_MAX; | |
1514 | int retval; | |
1515 | ||
1516 | retval = locks_mandatory_area(inode, file, pos, end, | |
1517 | write ? F_WRLCK : F_RDLCK); | |
1518 | if (retval < 0) | |
1519 | return retval; | |
1520 | } | |
1521 | ||
1522 | return security_file_permission(file, write ? MAY_WRITE : MAY_READ); | |
1523 | } | |
1524 | ||
1525 | int vfs_clone_file_range(struct file *file_in, loff_t pos_in, | |
1526 | struct file *file_out, loff_t pos_out, u64 len) | |
1527 | { | |
1528 | struct inode *inode_in = file_inode(file_in); | |
1529 | struct inode *inode_out = file_inode(file_out); | |
1530 | int ret; | |
1531 | ||
1532 | if (inode_in->i_sb != inode_out->i_sb || | |
1533 | file_in->f_path.mnt != file_out->f_path.mnt) | |
1534 | return -EXDEV; | |
1535 | ||
1536 | if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) | |
1537 | return -EISDIR; | |
1538 | if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) | |
d79bdd52 | 1539 | return -EINVAL; |
04b38d60 CH |
1540 | |
1541 | if (!(file_in->f_mode & FMODE_READ) || | |
1542 | !(file_out->f_mode & FMODE_WRITE) || | |
1543 | (file_out->f_flags & O_APPEND) || | |
1544 | !file_in->f_op->clone_file_range) | |
1545 | return -EBADF; | |
1546 | ||
1547 | ret = clone_verify_area(file_in, pos_in, len, false); | |
1548 | if (ret) | |
1549 | return ret; | |
1550 | ||
1551 | ret = clone_verify_area(file_out, pos_out, len, true); | |
1552 | if (ret) | |
1553 | return ret; | |
1554 | ||
1555 | if (pos_in + len > i_size_read(inode_in)) | |
1556 | return -EINVAL; | |
1557 | ||
1558 | ret = mnt_want_write_file(file_out); | |
1559 | if (ret) | |
1560 | return ret; | |
1561 | ||
1562 | ret = file_in->f_op->clone_file_range(file_in, pos_in, | |
1563 | file_out, pos_out, len); | |
1564 | if (!ret) { | |
1565 | fsnotify_access(file_in); | |
1566 | fsnotify_modify(file_out); | |
1567 | } | |
1568 | ||
1569 | mnt_drop_write_file(file_out); | |
1570 | return ret; | |
1571 | } | |
1572 | EXPORT_SYMBOL(vfs_clone_file_range); | |
54dbc151 DW |
1573 | |
1574 | int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) | |
1575 | { | |
1576 | struct file_dedupe_range_info *info; | |
1577 | struct inode *src = file_inode(file); | |
1578 | u64 off; | |
1579 | u64 len; | |
1580 | int i; | |
1581 | int ret; | |
1582 | bool is_admin = capable(CAP_SYS_ADMIN); | |
1583 | u16 count = same->dest_count; | |
1584 | struct file *dst_file; | |
1585 | loff_t dst_off; | |
1586 | ssize_t deduped; | |
1587 | ||
1588 | if (!(file->f_mode & FMODE_READ)) | |
1589 | return -EINVAL; | |
1590 | ||
1591 | if (same->reserved1 || same->reserved2) | |
1592 | return -EINVAL; | |
1593 | ||
1594 | off = same->src_offset; | |
1595 | len = same->src_length; | |
1596 | ||
1597 | ret = -EISDIR; | |
1598 | if (S_ISDIR(src->i_mode)) | |
1599 | goto out; | |
1600 | ||
1601 | ret = -EINVAL; | |
1602 | if (!S_ISREG(src->i_mode)) | |
1603 | goto out; | |
1604 | ||
1605 | ret = clone_verify_area(file, off, len, false); | |
1606 | if (ret < 0) | |
1607 | goto out; | |
1608 | ret = 0; | |
1609 | ||
1610 | /* pre-format output fields to sane values */ | |
1611 | for (i = 0; i < count; i++) { | |
1612 | same->info[i].bytes_deduped = 0ULL; | |
1613 | same->info[i].status = FILE_DEDUPE_RANGE_SAME; | |
1614 | } | |
1615 | ||
1616 | for (i = 0, info = same->info; i < count; i++, info++) { | |
1617 | struct inode *dst; | |
1618 | struct fd dst_fd = fdget(info->dest_fd); | |
1619 | ||
1620 | dst_file = dst_fd.file; | |
1621 | if (!dst_file) { | |
1622 | info->status = -EBADF; | |
1623 | goto next_loop; | |
1624 | } | |
1625 | dst = file_inode(dst_file); | |
1626 | ||
1627 | ret = mnt_want_write_file(dst_file); | |
1628 | if (ret) { | |
1629 | info->status = ret; | |
1630 | goto next_loop; | |
1631 | } | |
1632 | ||
1633 | dst_off = info->dest_offset; | |
1634 | ret = clone_verify_area(dst_file, dst_off, len, true); | |
1635 | if (ret < 0) { | |
1636 | info->status = ret; | |
1637 | goto next_file; | |
1638 | } | |
1639 | ret = 0; | |
1640 | ||
1641 | if (info->reserved) { | |
1642 | info->status = -EINVAL; | |
1643 | } else if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) { | |
1644 | info->status = -EINVAL; | |
1645 | } else if (file->f_path.mnt != dst_file->f_path.mnt) { | |
1646 | info->status = -EXDEV; | |
1647 | } else if (S_ISDIR(dst->i_mode)) { | |
1648 | info->status = -EISDIR; | |
1649 | } else if (dst_file->f_op->dedupe_file_range == NULL) { | |
1650 | info->status = -EINVAL; | |
1651 | } else { | |
1652 | deduped = dst_file->f_op->dedupe_file_range(file, off, | |
1653 | len, dst_file, | |
1654 | info->dest_offset); | |
1655 | if (deduped == -EBADE) | |
1656 | info->status = FILE_DEDUPE_RANGE_DIFFERS; | |
1657 | else if (deduped < 0) | |
1658 | info->status = deduped; | |
1659 | else | |
1660 | info->bytes_deduped += deduped; | |
1661 | } | |
1662 | ||
1663 | next_file: | |
1664 | mnt_drop_write_file(dst_file); | |
1665 | next_loop: | |
1666 | fdput(dst_fd); | |
e62e560f DW |
1667 | |
1668 | if (fatal_signal_pending(current)) | |
1669 | goto out; | |
54dbc151 DW |
1670 | } |
1671 | ||
1672 | out: | |
1673 | return ret; | |
1674 | } | |
1675 | EXPORT_SYMBOL(vfs_dedupe_file_range); |