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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> |
2feb55f8 | 20 | #include <linux/fs.h> |
06ae43f3 | 21 | #include "internal.h" |
1da177e4 | 22 | |
7c0f6ba6 | 23 | #include <linux/uaccess.h> |
1da177e4 LT |
24 | #include <asm/unistd.h> |
25 | ||
4b6f5d20 | 26 | const struct file_operations generic_ro_fops = { |
1da177e4 | 27 | .llseek = generic_file_llseek, |
aad4f8bb | 28 | .read_iter = generic_file_read_iter, |
1da177e4 | 29 | .mmap = generic_file_readonly_mmap, |
534f2aaa | 30 | .splice_read = generic_file_splice_read, |
1da177e4 LT |
31 | }; |
32 | ||
33 | EXPORT_SYMBOL(generic_ro_fops); | |
34 | ||
cccb5a1e | 35 | static inline int unsigned_offsets(struct file *file) |
4a3956c7 | 36 | { |
cccb5a1e | 37 | return file->f_mode & FMODE_UNSIGNED_OFFSET; |
4a3956c7 KH |
38 | } |
39 | ||
46a1c2c7 JL |
40 | /** |
41 | * vfs_setpos - update the file offset for lseek | |
42 | * @file: file structure in question | |
43 | * @offset: file offset to seek to | |
44 | * @maxsize: maximum file size | |
45 | * | |
46 | * This is a low-level filesystem helper for updating the file offset to | |
47 | * the value specified by @offset if the given offset is valid and it is | |
48 | * not equal to the current file offset. | |
49 | * | |
50 | * Return the specified offset on success and -EINVAL on invalid offset. | |
51 | */ | |
52 | loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize) | |
ef3d0fd2 AK |
53 | { |
54 | if (offset < 0 && !unsigned_offsets(file)) | |
55 | return -EINVAL; | |
56 | if (offset > maxsize) | |
57 | return -EINVAL; | |
58 | ||
59 | if (offset != file->f_pos) { | |
60 | file->f_pos = offset; | |
61 | file->f_version = 0; | |
62 | } | |
63 | return offset; | |
64 | } | |
46a1c2c7 | 65 | EXPORT_SYMBOL(vfs_setpos); |
ef3d0fd2 | 66 | |
3a8cff4f | 67 | /** |
5760495a | 68 | * generic_file_llseek_size - generic llseek implementation for regular files |
3a8cff4f CH |
69 | * @file: file structure to seek on |
70 | * @offset: file offset to seek to | |
965c8e59 | 71 | * @whence: type of seek |
e8b96eb5 ES |
72 | * @size: max size of this file in file system |
73 | * @eof: offset used for SEEK_END position | |
3a8cff4f | 74 | * |
5760495a | 75 | * This is a variant of generic_file_llseek that allows passing in a custom |
e8b96eb5 | 76 | * maximum file size and a custom EOF position, for e.g. hashed directories |
ef3d0fd2 AK |
77 | * |
78 | * Synchronization: | |
5760495a | 79 | * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms) |
ef3d0fd2 AK |
80 | * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes. |
81 | * read/writes behave like SEEK_SET against seeks. | |
3a8cff4f | 82 | */ |
9465efc9 | 83 | loff_t |
965c8e59 | 84 | generic_file_llseek_size(struct file *file, loff_t offset, int whence, |
e8b96eb5 | 85 | loff_t maxsize, loff_t eof) |
1da177e4 | 86 | { |
965c8e59 | 87 | switch (whence) { |
3a8cff4f | 88 | case SEEK_END: |
e8b96eb5 | 89 | offset += eof; |
3a8cff4f CH |
90 | break; |
91 | case SEEK_CUR: | |
5b6f1eb9 AK |
92 | /* |
93 | * Here we special-case the lseek(fd, 0, SEEK_CUR) | |
94 | * position-querying operation. Avoid rewriting the "same" | |
95 | * f_pos value back to the file because a concurrent read(), | |
96 | * write() or lseek() might have altered it | |
97 | */ | |
98 | if (offset == 0) | |
99 | return file->f_pos; | |
ef3d0fd2 AK |
100 | /* |
101 | * f_lock protects against read/modify/write race with other | |
102 | * SEEK_CURs. Note that parallel writes and reads behave | |
103 | * like SEEK_SET. | |
104 | */ | |
105 | spin_lock(&file->f_lock); | |
46a1c2c7 | 106 | offset = vfs_setpos(file, file->f_pos + offset, maxsize); |
ef3d0fd2 AK |
107 | spin_unlock(&file->f_lock); |
108 | return offset; | |
982d8165 JB |
109 | case SEEK_DATA: |
110 | /* | |
111 | * In the generic case the entire file is data, so as long as | |
112 | * offset isn't at the end of the file then the offset is data. | |
113 | */ | |
e8b96eb5 | 114 | if (offset >= eof) |
982d8165 JB |
115 | return -ENXIO; |
116 | break; | |
117 | case SEEK_HOLE: | |
118 | /* | |
119 | * There is a virtual hole at the end of the file, so as long as | |
120 | * offset isn't i_size or larger, return i_size. | |
121 | */ | |
e8b96eb5 | 122 | if (offset >= eof) |
982d8165 | 123 | return -ENXIO; |
e8b96eb5 | 124 | offset = eof; |
982d8165 | 125 | break; |
1da177e4 | 126 | } |
3a8cff4f | 127 | |
46a1c2c7 | 128 | return vfs_setpos(file, offset, maxsize); |
5760495a AK |
129 | } |
130 | EXPORT_SYMBOL(generic_file_llseek_size); | |
131 | ||
132 | /** | |
133 | * generic_file_llseek - generic llseek implementation for regular files | |
134 | * @file: file structure to seek on | |
135 | * @offset: file offset to seek to | |
965c8e59 | 136 | * @whence: type of seek |
5760495a AK |
137 | * |
138 | * This is a generic implemenation of ->llseek useable for all normal local | |
139 | * filesystems. It just updates the file offset to the value specified by | |
546ae2d2 | 140 | * @offset and @whence. |
5760495a | 141 | */ |
965c8e59 | 142 | loff_t generic_file_llseek(struct file *file, loff_t offset, int whence) |
5760495a AK |
143 | { |
144 | struct inode *inode = file->f_mapping->host; | |
145 | ||
965c8e59 | 146 | return generic_file_llseek_size(file, offset, whence, |
e8b96eb5 ES |
147 | inode->i_sb->s_maxbytes, |
148 | i_size_read(inode)); | |
1da177e4 | 149 | } |
9465efc9 | 150 | EXPORT_SYMBOL(generic_file_llseek); |
1da177e4 | 151 | |
1bf9d14d AV |
152 | /** |
153 | * fixed_size_llseek - llseek implementation for fixed-sized devices | |
154 | * @file: file structure to seek on | |
155 | * @offset: file offset to seek to | |
156 | * @whence: type of seek | |
157 | * @size: size of the file | |
158 | * | |
159 | */ | |
160 | loff_t fixed_size_llseek(struct file *file, loff_t offset, int whence, loff_t size) | |
161 | { | |
162 | switch (whence) { | |
163 | case SEEK_SET: case SEEK_CUR: case SEEK_END: | |
164 | return generic_file_llseek_size(file, offset, whence, | |
165 | size, size); | |
166 | default: | |
167 | return -EINVAL; | |
168 | } | |
169 | } | |
170 | EXPORT_SYMBOL(fixed_size_llseek); | |
171 | ||
b25472f9 AV |
172 | /** |
173 | * no_seek_end_llseek - llseek implementation for fixed-sized devices | |
174 | * @file: file structure to seek on | |
175 | * @offset: file offset to seek to | |
176 | * @whence: type of seek | |
177 | * | |
178 | */ | |
179 | loff_t no_seek_end_llseek(struct file *file, loff_t offset, int whence) | |
180 | { | |
181 | switch (whence) { | |
182 | case SEEK_SET: case SEEK_CUR: | |
183 | return generic_file_llseek_size(file, offset, whence, | |
2feb55f8 | 184 | OFFSET_MAX, 0); |
b25472f9 AV |
185 | default: |
186 | return -EINVAL; | |
187 | } | |
188 | } | |
189 | EXPORT_SYMBOL(no_seek_end_llseek); | |
190 | ||
191 | /** | |
192 | * no_seek_end_llseek_size - llseek implementation for fixed-sized devices | |
193 | * @file: file structure to seek on | |
194 | * @offset: file offset to seek to | |
195 | * @whence: type of seek | |
196 | * @size: maximal offset allowed | |
197 | * | |
198 | */ | |
199 | loff_t no_seek_end_llseek_size(struct file *file, loff_t offset, int whence, loff_t size) | |
200 | { | |
201 | switch (whence) { | |
202 | case SEEK_SET: case SEEK_CUR: | |
203 | return generic_file_llseek_size(file, offset, whence, | |
204 | size, 0); | |
205 | default: | |
206 | return -EINVAL; | |
207 | } | |
208 | } | |
209 | EXPORT_SYMBOL(no_seek_end_llseek_size); | |
210 | ||
ae6afc3f B |
211 | /** |
212 | * noop_llseek - No Operation Performed llseek implementation | |
213 | * @file: file structure to seek on | |
214 | * @offset: file offset to seek to | |
965c8e59 | 215 | * @whence: type of seek |
ae6afc3f B |
216 | * |
217 | * This is an implementation of ->llseek useable for the rare special case when | |
218 | * userspace expects the seek to succeed but the (device) file is actually not | |
219 | * able to perform the seek. In this case you use noop_llseek() instead of | |
220 | * falling back to the default implementation of ->llseek. | |
221 | */ | |
965c8e59 | 222 | loff_t noop_llseek(struct file *file, loff_t offset, int whence) |
ae6afc3f B |
223 | { |
224 | return file->f_pos; | |
225 | } | |
226 | EXPORT_SYMBOL(noop_llseek); | |
227 | ||
965c8e59 | 228 | loff_t no_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 LT |
229 | { |
230 | return -ESPIPE; | |
231 | } | |
232 | EXPORT_SYMBOL(no_llseek); | |
233 | ||
965c8e59 | 234 | loff_t default_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 | 235 | { |
496ad9aa | 236 | struct inode *inode = file_inode(file); |
16abef0e | 237 | loff_t retval; |
1da177e4 | 238 | |
5955102c | 239 | inode_lock(inode); |
965c8e59 | 240 | switch (whence) { |
7b8e8924 | 241 | case SEEK_END: |
982d8165 | 242 | offset += i_size_read(inode); |
1da177e4 | 243 | break; |
7b8e8924 | 244 | case SEEK_CUR: |
5b6f1eb9 AK |
245 | if (offset == 0) { |
246 | retval = file->f_pos; | |
247 | goto out; | |
248 | } | |
1da177e4 | 249 | offset += file->f_pos; |
982d8165 JB |
250 | break; |
251 | case SEEK_DATA: | |
252 | /* | |
253 | * In the generic case the entire file is data, so as | |
254 | * long as offset isn't at the end of the file then the | |
255 | * offset is data. | |
256 | */ | |
bacb2d81 DC |
257 | if (offset >= inode->i_size) { |
258 | retval = -ENXIO; | |
259 | goto out; | |
260 | } | |
982d8165 JB |
261 | break; |
262 | case SEEK_HOLE: | |
263 | /* | |
264 | * There is a virtual hole at the end of the file, so | |
265 | * as long as offset isn't i_size or larger, return | |
266 | * i_size. | |
267 | */ | |
bacb2d81 DC |
268 | if (offset >= inode->i_size) { |
269 | retval = -ENXIO; | |
270 | goto out; | |
271 | } | |
982d8165 JB |
272 | offset = inode->i_size; |
273 | break; | |
1da177e4 LT |
274 | } |
275 | retval = -EINVAL; | |
cccb5a1e | 276 | if (offset >= 0 || unsigned_offsets(file)) { |
1da177e4 LT |
277 | if (offset != file->f_pos) { |
278 | file->f_pos = offset; | |
279 | file->f_version = 0; | |
280 | } | |
281 | retval = offset; | |
282 | } | |
5b6f1eb9 | 283 | out: |
5955102c | 284 | inode_unlock(inode); |
1da177e4 LT |
285 | return retval; |
286 | } | |
287 | EXPORT_SYMBOL(default_llseek); | |
288 | ||
965c8e59 | 289 | loff_t vfs_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 LT |
290 | { |
291 | loff_t (*fn)(struct file *, loff_t, int); | |
292 | ||
293 | fn = no_llseek; | |
294 | if (file->f_mode & FMODE_LSEEK) { | |
72c2d531 | 295 | if (file->f_op->llseek) |
1da177e4 LT |
296 | fn = file->f_op->llseek; |
297 | } | |
965c8e59 | 298 | return fn(file, offset, whence); |
1da177e4 LT |
299 | } |
300 | EXPORT_SYMBOL(vfs_llseek); | |
301 | ||
965c8e59 | 302 | SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence) |
1da177e4 LT |
303 | { |
304 | off_t retval; | |
9c225f26 | 305 | struct fd f = fdget_pos(fd); |
2903ff01 AV |
306 | if (!f.file) |
307 | return -EBADF; | |
1da177e4 LT |
308 | |
309 | retval = -EINVAL; | |
965c8e59 AM |
310 | if (whence <= SEEK_MAX) { |
311 | loff_t res = vfs_llseek(f.file, offset, whence); | |
1da177e4 LT |
312 | retval = res; |
313 | if (res != (loff_t)retval) | |
314 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ | |
315 | } | |
9c225f26 | 316 | fdput_pos(f); |
1da177e4 LT |
317 | return retval; |
318 | } | |
319 | ||
561c6731 AV |
320 | #ifdef CONFIG_COMPAT |
321 | COMPAT_SYSCALL_DEFINE3(lseek, unsigned int, fd, compat_off_t, offset, unsigned int, whence) | |
322 | { | |
323 | return sys_lseek(fd, offset, whence); | |
324 | } | |
325 | #endif | |
326 | ||
1da177e4 | 327 | #ifdef __ARCH_WANT_SYS_LLSEEK |
003d7ab4 HC |
328 | SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, |
329 | unsigned long, offset_low, loff_t __user *, result, | |
965c8e59 | 330 | unsigned int, whence) |
1da177e4 LT |
331 | { |
332 | int retval; | |
d7a15f8d | 333 | struct fd f = fdget_pos(fd); |
1da177e4 | 334 | loff_t offset; |
1da177e4 | 335 | |
2903ff01 AV |
336 | if (!f.file) |
337 | return -EBADF; | |
1da177e4 LT |
338 | |
339 | retval = -EINVAL; | |
965c8e59 | 340 | if (whence > SEEK_MAX) |
1da177e4 LT |
341 | goto out_putf; |
342 | ||
2903ff01 | 343 | offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low, |
965c8e59 | 344 | whence); |
1da177e4 LT |
345 | |
346 | retval = (int)offset; | |
347 | if (offset >= 0) { | |
348 | retval = -EFAULT; | |
349 | if (!copy_to_user(result, &offset, sizeof(offset))) | |
350 | retval = 0; | |
351 | } | |
352 | out_putf: | |
d7a15f8d | 353 | fdput_pos(f); |
1da177e4 LT |
354 | return retval; |
355 | } | |
356 | #endif | |
357 | ||
dbe4e192 CH |
358 | ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos) |
359 | { | |
360 | struct kiocb kiocb; | |
361 | ssize_t ret; | |
362 | ||
363 | if (!file->f_op->read_iter) | |
364 | return -EINVAL; | |
365 | ||
366 | init_sync_kiocb(&kiocb, file); | |
367 | kiocb.ki_pos = *ppos; | |
dbe4e192 CH |
368 | |
369 | iter->type |= READ; | |
370 | ret = file->f_op->read_iter(&kiocb, iter); | |
599bd19b | 371 | BUG_ON(ret == -EIOCBQUEUED); |
dbe4e192 CH |
372 | if (ret > 0) |
373 | *ppos = kiocb.ki_pos; | |
374 | return ret; | |
375 | } | |
376 | EXPORT_SYMBOL(vfs_iter_read); | |
377 | ||
378 | ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos) | |
379 | { | |
380 | struct kiocb kiocb; | |
381 | ssize_t ret; | |
382 | ||
383 | if (!file->f_op->write_iter) | |
384 | return -EINVAL; | |
385 | ||
386 | init_sync_kiocb(&kiocb, file); | |
387 | kiocb.ki_pos = *ppos; | |
dbe4e192 CH |
388 | |
389 | iter->type |= WRITE; | |
390 | ret = file->f_op->write_iter(&kiocb, iter); | |
599bd19b | 391 | BUG_ON(ret == -EIOCBQUEUED); |
dbe4e192 CH |
392 | if (ret > 0) |
393 | *ppos = kiocb.ki_pos; | |
394 | return ret; | |
395 | } | |
396 | EXPORT_SYMBOL(vfs_iter_write); | |
397 | ||
68d70d03 | 398 | int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count) |
1da177e4 LT |
399 | { |
400 | struct inode *inode; | |
401 | loff_t pos; | |
c43e259c | 402 | int retval = -EINVAL; |
1da177e4 | 403 | |
496ad9aa | 404 | inode = file_inode(file); |
e28cc715 | 405 | if (unlikely((ssize_t) count < 0)) |
c43e259c | 406 | return retval; |
1da177e4 | 407 | pos = *ppos; |
cccb5a1e AV |
408 | if (unlikely(pos < 0)) { |
409 | if (!unsigned_offsets(file)) | |
410 | return retval; | |
411 | if (count >= -pos) /* both values are in 0..LLONG_MAX */ | |
412 | return -EOVERFLOW; | |
413 | } else if (unlikely((loff_t) (pos + count) < 0)) { | |
414 | if (!unsigned_offsets(file)) | |
4a3956c7 KH |
415 | return retval; |
416 | } | |
1da177e4 | 417 | |
bd61e0a9 | 418 | if (unlikely(inode->i_flctx && mandatory_lock(inode))) { |
acc15575 CH |
419 | retval = locks_mandatory_area(inode, file, pos, pos + count - 1, |
420 | read_write == READ ? F_RDLCK : F_WRLCK); | |
e28cc715 LT |
421 | if (retval < 0) |
422 | return retval; | |
423 | } | |
bc61384d | 424 | return security_file_permission(file, |
c43e259c | 425 | read_write == READ ? MAY_READ : MAY_WRITE); |
1da177e4 LT |
426 | } |
427 | ||
5d5d5689 | 428 | static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
293bc982 AV |
429 | { |
430 | struct iovec iov = { .iov_base = buf, .iov_len = len }; | |
431 | struct kiocb kiocb; | |
432 | struct iov_iter iter; | |
433 | ssize_t ret; | |
434 | ||
435 | init_sync_kiocb(&kiocb, filp); | |
436 | kiocb.ki_pos = *ppos; | |
293bc982 AV |
437 | iov_iter_init(&iter, READ, &iov, 1, len); |
438 | ||
439 | ret = filp->f_op->read_iter(&kiocb, &iter); | |
599bd19b | 440 | BUG_ON(ret == -EIOCBQUEUED); |
293bc982 AV |
441 | *ppos = kiocb.ki_pos; |
442 | return ret; | |
443 | } | |
444 | ||
6fb5032e DK |
445 | ssize_t __vfs_read(struct file *file, char __user *buf, size_t count, |
446 | loff_t *pos) | |
447 | { | |
6fb5032e | 448 | if (file->f_op->read) |
3d04c8a1 | 449 | return file->f_op->read(file, buf, count, pos); |
6fb5032e | 450 | else if (file->f_op->read_iter) |
3d04c8a1 | 451 | return new_sync_read(file, buf, count, pos); |
6fb5032e | 452 | else |
3d04c8a1 | 453 | return -EINVAL; |
6fb5032e | 454 | } |
3d04c8a1 | 455 | EXPORT_SYMBOL(__vfs_read); |
6fb5032e | 456 | |
1da177e4 LT |
457 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) |
458 | { | |
459 | ssize_t ret; | |
460 | ||
461 | if (!(file->f_mode & FMODE_READ)) | |
462 | return -EBADF; | |
7f7f25e8 | 463 | if (!(file->f_mode & FMODE_CAN_READ)) |
1da177e4 LT |
464 | return -EINVAL; |
465 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) | |
466 | return -EFAULT; | |
467 | ||
468 | ret = rw_verify_area(READ, file, pos, count); | |
bc61384d AV |
469 | if (!ret) { |
470 | if (count > MAX_RW_COUNT) | |
471 | count = MAX_RW_COUNT; | |
6fb5032e | 472 | ret = __vfs_read(file, buf, count, pos); |
c43e259c | 473 | if (ret > 0) { |
2a12a9d7 | 474 | fsnotify_access(file); |
c43e259c | 475 | add_rchar(current, ret); |
1da177e4 | 476 | } |
c43e259c | 477 | inc_syscr(current); |
1da177e4 LT |
478 | } |
479 | ||
480 | return ret; | |
481 | } | |
482 | ||
483 | EXPORT_SYMBOL(vfs_read); | |
484 | ||
5d5d5689 | 485 | static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) |
293bc982 AV |
486 | { |
487 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; | |
488 | struct kiocb kiocb; | |
489 | struct iov_iter iter; | |
490 | ssize_t ret; | |
491 | ||
492 | init_sync_kiocb(&kiocb, filp); | |
493 | kiocb.ki_pos = *ppos; | |
293bc982 AV |
494 | iov_iter_init(&iter, WRITE, &iov, 1, len); |
495 | ||
496 | ret = filp->f_op->write_iter(&kiocb, &iter); | |
599bd19b | 497 | BUG_ON(ret == -EIOCBQUEUED); |
f765b134 AV |
498 | if (ret > 0) |
499 | *ppos = kiocb.ki_pos; | |
293bc982 AV |
500 | return ret; |
501 | } | |
502 | ||
493c84c0 AV |
503 | ssize_t __vfs_write(struct file *file, const char __user *p, size_t count, |
504 | loff_t *pos) | |
505 | { | |
506 | if (file->f_op->write) | |
507 | return file->f_op->write(file, p, count, pos); | |
493c84c0 AV |
508 | else if (file->f_op->write_iter) |
509 | return new_sync_write(file, p, count, pos); | |
510 | else | |
511 | return -EINVAL; | |
512 | } | |
513 | EXPORT_SYMBOL(__vfs_write); | |
514 | ||
06ae43f3 AV |
515 | ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos) |
516 | { | |
517 | mm_segment_t old_fs; | |
518 | const char __user *p; | |
519 | ssize_t ret; | |
520 | ||
7f7f25e8 | 521 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
3e84f48e AV |
522 | return -EINVAL; |
523 | ||
06ae43f3 AV |
524 | old_fs = get_fs(); |
525 | set_fs(get_ds()); | |
526 | p = (__force const char __user *)buf; | |
527 | if (count > MAX_RW_COUNT) | |
528 | count = MAX_RW_COUNT; | |
493c84c0 | 529 | ret = __vfs_write(file, p, count, pos); |
06ae43f3 AV |
530 | set_fs(old_fs); |
531 | if (ret > 0) { | |
532 | fsnotify_modify(file); | |
533 | add_wchar(current, ret); | |
534 | } | |
535 | inc_syscw(current); | |
536 | return ret; | |
537 | } | |
538 | ||
2ec3a12a AV |
539 | EXPORT_SYMBOL(__kernel_write); |
540 | ||
1da177e4 LT |
541 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
542 | { | |
543 | ssize_t ret; | |
544 | ||
545 | if (!(file->f_mode & FMODE_WRITE)) | |
546 | return -EBADF; | |
7f7f25e8 | 547 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
1da177e4 LT |
548 | return -EINVAL; |
549 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) | |
550 | return -EFAULT; | |
551 | ||
552 | ret = rw_verify_area(WRITE, file, pos, count); | |
bc61384d AV |
553 | if (!ret) { |
554 | if (count > MAX_RW_COUNT) | |
555 | count = MAX_RW_COUNT; | |
03d95eb2 | 556 | file_start_write(file); |
493c84c0 | 557 | ret = __vfs_write(file, buf, count, pos); |
c43e259c | 558 | if (ret > 0) { |
2a12a9d7 | 559 | fsnotify_modify(file); |
c43e259c | 560 | add_wchar(current, ret); |
1da177e4 | 561 | } |
c43e259c | 562 | inc_syscw(current); |
03d95eb2 | 563 | file_end_write(file); |
1da177e4 LT |
564 | } |
565 | ||
566 | return ret; | |
567 | } | |
568 | ||
569 | EXPORT_SYMBOL(vfs_write); | |
570 | ||
571 | static inline loff_t file_pos_read(struct file *file) | |
572 | { | |
573 | return file->f_pos; | |
574 | } | |
575 | ||
576 | static inline void file_pos_write(struct file *file, loff_t pos) | |
577 | { | |
578 | file->f_pos = pos; | |
579 | } | |
580 | ||
3cdad428 | 581 | SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) |
1da177e4 | 582 | { |
9c225f26 | 583 | struct fd f = fdget_pos(fd); |
1da177e4 | 584 | ssize_t ret = -EBADF; |
1da177e4 | 585 | |
2903ff01 AV |
586 | if (f.file) { |
587 | loff_t pos = file_pos_read(f.file); | |
588 | ret = vfs_read(f.file, buf, count, &pos); | |
5faf153e AV |
589 | if (ret >= 0) |
590 | file_pos_write(f.file, pos); | |
9c225f26 | 591 | fdput_pos(f); |
1da177e4 | 592 | } |
1da177e4 LT |
593 | return ret; |
594 | } | |
1da177e4 | 595 | |
3cdad428 HC |
596 | SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, |
597 | size_t, count) | |
1da177e4 | 598 | { |
9c225f26 | 599 | struct fd f = fdget_pos(fd); |
1da177e4 | 600 | ssize_t ret = -EBADF; |
1da177e4 | 601 | |
2903ff01 AV |
602 | if (f.file) { |
603 | loff_t pos = file_pos_read(f.file); | |
604 | ret = vfs_write(f.file, buf, count, &pos); | |
5faf153e AV |
605 | if (ret >= 0) |
606 | file_pos_write(f.file, pos); | |
9c225f26 | 607 | fdput_pos(f); |
1da177e4 LT |
608 | } |
609 | ||
610 | return ret; | |
611 | } | |
612 | ||
4a0fd5bf AV |
613 | SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, |
614 | size_t, count, loff_t, pos) | |
1da177e4 | 615 | { |
2903ff01 | 616 | struct fd f; |
1da177e4 | 617 | ssize_t ret = -EBADF; |
1da177e4 LT |
618 | |
619 | if (pos < 0) | |
620 | return -EINVAL; | |
621 | ||
2903ff01 AV |
622 | f = fdget(fd); |
623 | if (f.file) { | |
1da177e4 | 624 | ret = -ESPIPE; |
2903ff01 AV |
625 | if (f.file->f_mode & FMODE_PREAD) |
626 | ret = vfs_read(f.file, buf, count, &pos); | |
627 | fdput(f); | |
1da177e4 LT |
628 | } |
629 | ||
630 | return ret; | |
631 | } | |
632 | ||
4a0fd5bf AV |
633 | SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const 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_PWRITE) |
646 | ret = vfs_write(f.file, buf, count, &pos); | |
647 | fdput(f); | |
1da177e4 LT |
648 | } |
649 | ||
650 | return ret; | |
651 | } | |
652 | ||
653 | /* | |
654 | * Reduce an iovec's length in-place. Return the resulting number of segments | |
655 | */ | |
656 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) | |
657 | { | |
658 | unsigned long seg = 0; | |
659 | size_t len = 0; | |
660 | ||
661 | while (seg < nr_segs) { | |
662 | seg++; | |
663 | if (len + iov->iov_len >= to) { | |
664 | iov->iov_len = to - len; | |
665 | break; | |
666 | } | |
667 | len += iov->iov_len; | |
668 | iov++; | |
669 | } | |
670 | return seg; | |
671 | } | |
19295529 | 672 | EXPORT_SYMBOL(iov_shorten); |
1da177e4 | 673 | |
ac15ac06 | 674 | static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, |
0f78d06a | 675 | loff_t *ppos, int type, int flags) |
293bc982 AV |
676 | { |
677 | struct kiocb kiocb; | |
293bc982 AV |
678 | ssize_t ret; |
679 | ||
e864f395 | 680 | if (flags & ~(RWF_HIPRI | RWF_DSYNC | RWF_SYNC)) |
793b80ef CH |
681 | return -EOPNOTSUPP; |
682 | ||
293bc982 | 683 | init_sync_kiocb(&kiocb, filp); |
97be7ebe CH |
684 | if (flags & RWF_HIPRI) |
685 | kiocb.ki_flags |= IOCB_HIPRI; | |
e864f395 CH |
686 | if (flags & RWF_DSYNC) |
687 | kiocb.ki_flags |= IOCB_DSYNC; | |
688 | if (flags & RWF_SYNC) | |
689 | kiocb.ki_flags |= (IOCB_DSYNC | IOCB_SYNC); | |
293bc982 | 690 | kiocb.ki_pos = *ppos; |
293bc982 | 691 | |
0f78d06a MS |
692 | if (type == READ) |
693 | ret = filp->f_op->read_iter(&kiocb, iter); | |
694 | else | |
695 | ret = filp->f_op->write_iter(&kiocb, iter); | |
599bd19b | 696 | BUG_ON(ret == -EIOCBQUEUED); |
293bc982 AV |
697 | *ppos = kiocb.ki_pos; |
698 | return ret; | |
699 | } | |
700 | ||
ee0b3e67 | 701 | /* Do it by hand, with file-ops */ |
ac15ac06 | 702 | static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, |
0f78d06a | 703 | loff_t *ppos, int type, int flags) |
ee0b3e67 | 704 | { |
ee0b3e67 BP |
705 | ssize_t ret = 0; |
706 | ||
97be7ebe | 707 | if (flags & ~RWF_HIPRI) |
793b80ef CH |
708 | return -EOPNOTSUPP; |
709 | ||
ac15ac06 AV |
710 | while (iov_iter_count(iter)) { |
711 | struct iovec iovec = iov_iter_iovec(iter); | |
ee0b3e67 BP |
712 | ssize_t nr; |
713 | ||
0f78d06a MS |
714 | if (type == READ) { |
715 | nr = filp->f_op->read(filp, iovec.iov_base, | |
716 | iovec.iov_len, ppos); | |
717 | } else { | |
718 | nr = filp->f_op->write(filp, iovec.iov_base, | |
719 | iovec.iov_len, ppos); | |
720 | } | |
ee0b3e67 BP |
721 | |
722 | if (nr < 0) { | |
723 | if (!ret) | |
724 | ret = nr; | |
725 | break; | |
726 | } | |
727 | ret += nr; | |
ac15ac06 | 728 | if (nr != iovec.iov_len) |
ee0b3e67 | 729 | break; |
ac15ac06 | 730 | iov_iter_advance(iter, nr); |
ee0b3e67 BP |
731 | } |
732 | ||
733 | return ret; | |
734 | } | |
735 | ||
1da177e4 LT |
736 | /* A write operation does a read from user space and vice versa */ |
737 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) | |
738 | ||
ffecee4f VN |
739 | /** |
740 | * rw_copy_check_uvector() - Copy an array of &struct iovec from userspace | |
741 | * into the kernel and check that it is valid. | |
742 | * | |
743 | * @type: One of %CHECK_IOVEC_ONLY, %READ, or %WRITE. | |
744 | * @uvector: Pointer to the userspace array. | |
745 | * @nr_segs: Number of elements in userspace array. | |
746 | * @fast_segs: Number of elements in @fast_pointer. | |
747 | * @fast_pointer: Pointer to (usually small on-stack) kernel array. | |
748 | * @ret_pointer: (output parameter) Pointer to a variable that will point to | |
749 | * either @fast_pointer, a newly allocated kernel array, or NULL, | |
750 | * depending on which array was used. | |
751 | * | |
752 | * This function copies an array of &struct iovec of @nr_segs from | |
753 | * userspace into the kernel and checks that each element is valid (e.g. | |
754 | * it does not point to a kernel address or cause overflow by being too | |
755 | * large, etc.). | |
756 | * | |
757 | * As an optimization, the caller may provide a pointer to a small | |
758 | * on-stack array in @fast_pointer, typically %UIO_FASTIOV elements long | |
759 | * (the size of this array, or 0 if unused, should be given in @fast_segs). | |
760 | * | |
761 | * @ret_pointer will always point to the array that was used, so the | |
762 | * caller must take care not to call kfree() on it e.g. in case the | |
763 | * @fast_pointer array was used and it was allocated on the stack. | |
764 | * | |
765 | * Return: The total number of bytes covered by the iovec array on success | |
766 | * or a negative error code on error. | |
767 | */ | |
eed4e51f BP |
768 | ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, |
769 | unsigned long nr_segs, unsigned long fast_segs, | |
770 | struct iovec *fast_pointer, | |
ac34ebb3 | 771 | struct iovec **ret_pointer) |
435f49a5 | 772 | { |
eed4e51f | 773 | unsigned long seg; |
435f49a5 | 774 | ssize_t ret; |
eed4e51f BP |
775 | struct iovec *iov = fast_pointer; |
776 | ||
435f49a5 LT |
777 | /* |
778 | * SuS says "The readv() function *may* fail if the iovcnt argument | |
779 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has | |
780 | * traditionally returned zero for zero segments, so... | |
781 | */ | |
eed4e51f BP |
782 | if (nr_segs == 0) { |
783 | ret = 0; | |
435f49a5 | 784 | goto out; |
eed4e51f BP |
785 | } |
786 | ||
435f49a5 LT |
787 | /* |
788 | * First get the "struct iovec" from user memory and | |
789 | * verify all the pointers | |
790 | */ | |
eed4e51f BP |
791 | if (nr_segs > UIO_MAXIOV) { |
792 | ret = -EINVAL; | |
435f49a5 | 793 | goto out; |
eed4e51f BP |
794 | } |
795 | if (nr_segs > fast_segs) { | |
435f49a5 | 796 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); |
eed4e51f BP |
797 | if (iov == NULL) { |
798 | ret = -ENOMEM; | |
435f49a5 | 799 | goto out; |
eed4e51f | 800 | } |
435f49a5 | 801 | } |
eed4e51f BP |
802 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { |
803 | ret = -EFAULT; | |
435f49a5 | 804 | goto out; |
eed4e51f BP |
805 | } |
806 | ||
435f49a5 | 807 | /* |
eed4e51f BP |
808 | * According to the Single Unix Specification we should return EINVAL |
809 | * if an element length is < 0 when cast to ssize_t or if the | |
810 | * total length would overflow the ssize_t return value of the | |
811 | * system call. | |
435f49a5 LT |
812 | * |
813 | * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the | |
814 | * overflow case. | |
815 | */ | |
eed4e51f | 816 | ret = 0; |
435f49a5 LT |
817 | for (seg = 0; seg < nr_segs; seg++) { |
818 | void __user *buf = iov[seg].iov_base; | |
819 | ssize_t len = (ssize_t)iov[seg].iov_len; | |
eed4e51f BP |
820 | |
821 | /* see if we we're about to use an invalid len or if | |
822 | * it's about to overflow ssize_t */ | |
435f49a5 | 823 | if (len < 0) { |
eed4e51f | 824 | ret = -EINVAL; |
435f49a5 | 825 | goto out; |
eed4e51f | 826 | } |
ac34ebb3 | 827 | if (type >= 0 |
fcf63409 | 828 | && unlikely(!access_ok(vrfy_dir(type), buf, len))) { |
eed4e51f | 829 | ret = -EFAULT; |
435f49a5 LT |
830 | goto out; |
831 | } | |
832 | if (len > MAX_RW_COUNT - ret) { | |
833 | len = MAX_RW_COUNT - ret; | |
834 | iov[seg].iov_len = len; | |
eed4e51f | 835 | } |
eed4e51f | 836 | ret += len; |
435f49a5 | 837 | } |
eed4e51f BP |
838 | out: |
839 | *ret_pointer = iov; | |
840 | return ret; | |
841 | } | |
842 | ||
7687a7a4 MS |
843 | static ssize_t __do_readv_writev(int type, struct file *file, |
844 | struct iov_iter *iter, loff_t *pos, int flags) | |
1da177e4 | 845 | { |
1da177e4 | 846 | size_t tot_len; |
7687a7a4 | 847 | ssize_t ret = 0; |
1da177e4 | 848 | |
7687a7a4 | 849 | tot_len = iov_iter_count(iter); |
0504c074 AV |
850 | if (!tot_len) |
851 | goto out; | |
1da177e4 | 852 | ret = rw_verify_area(type, file, pos, tot_len); |
e28cc715 | 853 | if (ret < 0) |
411b67b4 | 854 | goto out; |
1da177e4 | 855 | |
0f78d06a | 856 | if (type != READ) |
03d95eb2 | 857 | file_start_write(file); |
1da177e4 | 858 | |
0f78d06a MS |
859 | if ((type == READ && file->f_op->read_iter) || |
860 | (type == WRITE && file->f_op->write_iter)) | |
861 | ret = do_iter_readv_writev(file, iter, pos, type, flags); | |
ee0b3e67 | 862 | else |
0f78d06a | 863 | ret = do_loop_readv_writev(file, iter, pos, type, flags); |
1da177e4 | 864 | |
03d95eb2 AV |
865 | if (type != READ) |
866 | file_end_write(file); | |
867 | ||
1da177e4 | 868 | out: |
0eeca283 RL |
869 | if ((ret + (type == READ)) > 0) { |
870 | if (type == READ) | |
2a12a9d7 | 871 | fsnotify_access(file); |
0eeca283 | 872 | else |
2a12a9d7 | 873 | fsnotify_modify(file); |
0eeca283 | 874 | } |
1da177e4 | 875 | return ret; |
1da177e4 LT |
876 | } |
877 | ||
7687a7a4 MS |
878 | static ssize_t do_readv_writev(int type, struct file *file, |
879 | const struct iovec __user *uvector, | |
880 | unsigned long nr_segs, loff_t *pos, | |
881 | int flags) | |
882 | { | |
883 | struct iovec iovstack[UIO_FASTIOV]; | |
884 | struct iovec *iov = iovstack; | |
885 | struct iov_iter iter; | |
886 | ssize_t ret; | |
887 | ||
888 | ret = import_iovec(type, uvector, nr_segs, | |
889 | ARRAY_SIZE(iovstack), &iov, &iter); | |
890 | if (ret < 0) | |
891 | return ret; | |
892 | ||
893 | ret = __do_readv_writev(type, file, &iter, pos, flags); | |
894 | kfree(iov); | |
895 | ||
896 | return ret; | |
897 | } | |
898 | ||
1da177e4 | 899 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, |
793b80ef | 900 | unsigned long vlen, loff_t *pos, int flags) |
1da177e4 LT |
901 | { |
902 | if (!(file->f_mode & FMODE_READ)) | |
903 | return -EBADF; | |
7f7f25e8 | 904 | if (!(file->f_mode & FMODE_CAN_READ)) |
1da177e4 LT |
905 | return -EINVAL; |
906 | ||
793b80ef | 907 | return do_readv_writev(READ, file, vec, vlen, pos, flags); |
1da177e4 LT |
908 | } |
909 | ||
910 | EXPORT_SYMBOL(vfs_readv); | |
911 | ||
912 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, | |
793b80ef | 913 | unsigned long vlen, loff_t *pos, int flags) |
1da177e4 LT |
914 | { |
915 | if (!(file->f_mode & FMODE_WRITE)) | |
916 | return -EBADF; | |
7f7f25e8 | 917 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
1da177e4 LT |
918 | return -EINVAL; |
919 | ||
793b80ef | 920 | return do_readv_writev(WRITE, file, vec, vlen, pos, flags); |
1da177e4 LT |
921 | } |
922 | ||
923 | EXPORT_SYMBOL(vfs_writev); | |
924 | ||
f17d8b35 MT |
925 | static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec, |
926 | unsigned long vlen, int flags) | |
1da177e4 | 927 | { |
9c225f26 | 928 | struct fd f = fdget_pos(fd); |
1da177e4 | 929 | ssize_t ret = -EBADF; |
1da177e4 | 930 | |
2903ff01 AV |
931 | if (f.file) { |
932 | loff_t pos = file_pos_read(f.file); | |
f17d8b35 | 933 | ret = vfs_readv(f.file, vec, vlen, &pos, flags); |
5faf153e AV |
934 | if (ret >= 0) |
935 | file_pos_write(f.file, pos); | |
9c225f26 | 936 | fdput_pos(f); |
1da177e4 LT |
937 | } |
938 | ||
939 | if (ret > 0) | |
4b98d11b AD |
940 | add_rchar(current, ret); |
941 | inc_syscr(current); | |
1da177e4 LT |
942 | return ret; |
943 | } | |
944 | ||
f17d8b35 MT |
945 | static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec, |
946 | unsigned long vlen, int flags) | |
1da177e4 | 947 | { |
9c225f26 | 948 | struct fd f = fdget_pos(fd); |
1da177e4 | 949 | ssize_t ret = -EBADF; |
1da177e4 | 950 | |
2903ff01 AV |
951 | if (f.file) { |
952 | loff_t pos = file_pos_read(f.file); | |
f17d8b35 | 953 | ret = vfs_writev(f.file, vec, vlen, &pos, flags); |
5faf153e AV |
954 | if (ret >= 0) |
955 | file_pos_write(f.file, pos); | |
9c225f26 | 956 | fdput_pos(f); |
1da177e4 LT |
957 | } |
958 | ||
959 | if (ret > 0) | |
4b98d11b AD |
960 | add_wchar(current, ret); |
961 | inc_syscw(current); | |
1da177e4 LT |
962 | return ret; |
963 | } | |
964 | ||
601cc11d LT |
965 | static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) |
966 | { | |
967 | #define HALF_LONG_BITS (BITS_PER_LONG / 2) | |
968 | return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; | |
969 | } | |
970 | ||
f17d8b35 MT |
971 | static ssize_t do_preadv(unsigned long fd, const struct iovec __user *vec, |
972 | unsigned long vlen, loff_t pos, int flags) | |
f3554f4b | 973 | { |
2903ff01 | 974 | struct fd f; |
f3554f4b | 975 | ssize_t ret = -EBADF; |
f3554f4b GH |
976 | |
977 | if (pos < 0) | |
978 | return -EINVAL; | |
979 | ||
2903ff01 AV |
980 | f = fdget(fd); |
981 | if (f.file) { | |
f3554f4b | 982 | ret = -ESPIPE; |
2903ff01 | 983 | if (f.file->f_mode & FMODE_PREAD) |
f17d8b35 | 984 | ret = vfs_readv(f.file, vec, vlen, &pos, flags); |
2903ff01 | 985 | fdput(f); |
f3554f4b GH |
986 | } |
987 | ||
988 | if (ret > 0) | |
989 | add_rchar(current, ret); | |
990 | inc_syscr(current); | |
991 | return ret; | |
992 | } | |
993 | ||
f17d8b35 MT |
994 | static ssize_t do_pwritev(unsigned long fd, const struct iovec __user *vec, |
995 | unsigned long vlen, loff_t pos, int flags) | |
f3554f4b | 996 | { |
2903ff01 | 997 | struct fd f; |
f3554f4b | 998 | ssize_t ret = -EBADF; |
f3554f4b GH |
999 | |
1000 | if (pos < 0) | |
1001 | return -EINVAL; | |
1002 | ||
2903ff01 AV |
1003 | f = fdget(fd); |
1004 | if (f.file) { | |
f3554f4b | 1005 | ret = -ESPIPE; |
2903ff01 | 1006 | if (f.file->f_mode & FMODE_PWRITE) |
f17d8b35 | 1007 | ret = vfs_writev(f.file, vec, vlen, &pos, flags); |
2903ff01 | 1008 | fdput(f); |
f3554f4b GH |
1009 | } |
1010 | ||
1011 | if (ret > 0) | |
1012 | add_wchar(current, ret); | |
1013 | inc_syscw(current); | |
1014 | return ret; | |
1015 | } | |
1016 | ||
f17d8b35 MT |
1017 | SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, |
1018 | unsigned long, vlen) | |
1019 | { | |
1020 | return do_readv(fd, vec, vlen, 0); | |
1021 | } | |
1022 | ||
1023 | SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, | |
1024 | unsigned long, vlen) | |
1025 | { | |
1026 | return do_writev(fd, vec, vlen, 0); | |
1027 | } | |
1028 | ||
1029 | SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, | |
1030 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) | |
1031 | { | |
1032 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1033 | ||
1034 | return do_preadv(fd, vec, vlen, pos, 0); | |
1035 | } | |
1036 | ||
1037 | SYSCALL_DEFINE6(preadv2, unsigned long, fd, const struct iovec __user *, vec, | |
1038 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h, | |
1039 | int, flags) | |
1040 | { | |
1041 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1042 | ||
1043 | if (pos == -1) | |
1044 | return do_readv(fd, vec, vlen, flags); | |
1045 | ||
1046 | return do_preadv(fd, vec, vlen, pos, flags); | |
1047 | } | |
1048 | ||
1049 | SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, | |
1050 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) | |
1051 | { | |
1052 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1053 | ||
1054 | return do_pwritev(fd, vec, vlen, pos, 0); | |
1055 | } | |
1056 | ||
1057 | SYSCALL_DEFINE6(pwritev2, unsigned long, fd, const struct iovec __user *, vec, | |
1058 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h, | |
1059 | int, flags) | |
1060 | { | |
1061 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1062 | ||
1063 | if (pos == -1) | |
1064 | return do_writev(fd, vec, vlen, flags); | |
1065 | ||
1066 | return do_pwritev(fd, vec, vlen, pos, flags); | |
1067 | } | |
1068 | ||
72ec3516 AV |
1069 | #ifdef CONFIG_COMPAT |
1070 | ||
1071 | static ssize_t compat_do_readv_writev(int type, struct file *file, | |
1072 | const struct compat_iovec __user *uvector, | |
793b80ef CH |
1073 | unsigned long nr_segs, loff_t *pos, |
1074 | int flags) | |
72ec3516 | 1075 | { |
72ec3516 AV |
1076 | struct iovec iovstack[UIO_FASTIOV]; |
1077 | struct iovec *iov = iovstack; | |
ac15ac06 | 1078 | struct iov_iter iter; |
72ec3516 | 1079 | ssize_t ret; |
72ec3516 | 1080 | |
0504c074 AV |
1081 | ret = compat_import_iovec(type, uvector, nr_segs, |
1082 | UIO_FASTIOV, &iov, &iter); | |
1083 | if (ret < 0) | |
1084 | return ret; | |
72ec3516 | 1085 | |
7687a7a4 | 1086 | ret = __do_readv_writev(type, file, &iter, pos, flags); |
0504c074 | 1087 | kfree(iov); |
7687a7a4 | 1088 | |
72ec3516 AV |
1089 | return ret; |
1090 | } | |
1091 | ||
1092 | static size_t compat_readv(struct file *file, | |
1093 | const struct compat_iovec __user *vec, | |
f17d8b35 | 1094 | unsigned long vlen, loff_t *pos, int flags) |
72ec3516 AV |
1095 | { |
1096 | ssize_t ret = -EBADF; | |
1097 | ||
1098 | if (!(file->f_mode & FMODE_READ)) | |
1099 | goto out; | |
1100 | ||
1101 | ret = -EINVAL; | |
7f7f25e8 | 1102 | if (!(file->f_mode & FMODE_CAN_READ)) |
72ec3516 AV |
1103 | goto out; |
1104 | ||
f17d8b35 | 1105 | ret = compat_do_readv_writev(READ, file, vec, vlen, pos, flags); |
72ec3516 AV |
1106 | |
1107 | out: | |
1108 | if (ret > 0) | |
1109 | add_rchar(current, ret); | |
1110 | inc_syscr(current); | |
1111 | return ret; | |
1112 | } | |
1113 | ||
f17d8b35 MT |
1114 | static size_t do_compat_readv(compat_ulong_t fd, |
1115 | const struct compat_iovec __user *vec, | |
1116 | compat_ulong_t vlen, int flags) | |
72ec3516 | 1117 | { |
9c225f26 | 1118 | struct fd f = fdget_pos(fd); |
72ec3516 AV |
1119 | ssize_t ret; |
1120 | loff_t pos; | |
1121 | ||
1122 | if (!f.file) | |
1123 | return -EBADF; | |
1124 | pos = f.file->f_pos; | |
f17d8b35 | 1125 | ret = compat_readv(f.file, vec, vlen, &pos, flags); |
5faf153e AV |
1126 | if (ret >= 0) |
1127 | f.file->f_pos = pos; | |
9c225f26 | 1128 | fdput_pos(f); |
72ec3516 | 1129 | return ret; |
f17d8b35 | 1130 | |
72ec3516 AV |
1131 | } |
1132 | ||
f17d8b35 MT |
1133 | COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, |
1134 | const struct compat_iovec __user *,vec, | |
1135 | compat_ulong_t, vlen) | |
1136 | { | |
1137 | return do_compat_readv(fd, vec, vlen, 0); | |
1138 | } | |
1139 | ||
1140 | static long do_compat_preadv64(unsigned long fd, | |
378a10f3 | 1141 | const struct compat_iovec __user *vec, |
f17d8b35 | 1142 | unsigned long vlen, loff_t pos, int flags) |
72ec3516 AV |
1143 | { |
1144 | struct fd f; | |
1145 | ssize_t ret; | |
1146 | ||
1147 | if (pos < 0) | |
1148 | return -EINVAL; | |
1149 | f = fdget(fd); | |
1150 | if (!f.file) | |
1151 | return -EBADF; | |
1152 | ret = -ESPIPE; | |
1153 | if (f.file->f_mode & FMODE_PREAD) | |
f17d8b35 | 1154 | ret = compat_readv(f.file, vec, vlen, &pos, flags); |
72ec3516 AV |
1155 | fdput(f); |
1156 | return ret; | |
1157 | } | |
1158 | ||
378a10f3 HC |
1159 | #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64 |
1160 | COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, | |
1161 | const struct compat_iovec __user *,vec, | |
1162 | unsigned long, vlen, loff_t, pos) | |
1163 | { | |
f17d8b35 | 1164 | return do_compat_preadv64(fd, vec, vlen, pos, 0); |
378a10f3 HC |
1165 | } |
1166 | #endif | |
1167 | ||
dfd948e3 | 1168 | COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, |
72ec3516 | 1169 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1170 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1171 | { |
1172 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 | 1173 | |
f17d8b35 MT |
1174 | return do_compat_preadv64(fd, vec, vlen, pos, 0); |
1175 | } | |
1176 | ||
3ebfd81f L |
1177 | #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64V2 |
1178 | COMPAT_SYSCALL_DEFINE5(preadv64v2, unsigned long, fd, | |
1179 | const struct compat_iovec __user *,vec, | |
1180 | unsigned long, vlen, loff_t, pos, int, flags) | |
1181 | { | |
1182 | return do_compat_preadv64(fd, vec, vlen, pos, flags); | |
1183 | } | |
1184 | #endif | |
1185 | ||
f17d8b35 MT |
1186 | COMPAT_SYSCALL_DEFINE6(preadv2, compat_ulong_t, fd, |
1187 | const struct compat_iovec __user *,vec, | |
1188 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high, | |
1189 | int, flags) | |
1190 | { | |
1191 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
1192 | ||
1193 | if (pos == -1) | |
1194 | return do_compat_readv(fd, vec, vlen, flags); | |
1195 | ||
1196 | return do_compat_preadv64(fd, vec, vlen, pos, flags); | |
72ec3516 AV |
1197 | } |
1198 | ||
1199 | static size_t compat_writev(struct file *file, | |
1200 | const struct compat_iovec __user *vec, | |
f17d8b35 | 1201 | unsigned long vlen, loff_t *pos, int flags) |
72ec3516 AV |
1202 | { |
1203 | ssize_t ret = -EBADF; | |
1204 | ||
1205 | if (!(file->f_mode & FMODE_WRITE)) | |
1206 | goto out; | |
1207 | ||
1208 | ret = -EINVAL; | |
7f7f25e8 | 1209 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
72ec3516 AV |
1210 | goto out; |
1211 | ||
793b80ef | 1212 | ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos, 0); |
72ec3516 AV |
1213 | |
1214 | out: | |
1215 | if (ret > 0) | |
1216 | add_wchar(current, ret); | |
1217 | inc_syscw(current); | |
1218 | return ret; | |
1219 | } | |
1220 | ||
f17d8b35 MT |
1221 | static size_t do_compat_writev(compat_ulong_t fd, |
1222 | const struct compat_iovec __user* vec, | |
1223 | compat_ulong_t vlen, int flags) | |
72ec3516 | 1224 | { |
9c225f26 | 1225 | struct fd f = fdget_pos(fd); |
72ec3516 AV |
1226 | ssize_t ret; |
1227 | loff_t pos; | |
1228 | ||
1229 | if (!f.file) | |
1230 | return -EBADF; | |
1231 | pos = f.file->f_pos; | |
f17d8b35 | 1232 | ret = compat_writev(f.file, vec, vlen, &pos, flags); |
5faf153e AV |
1233 | if (ret >= 0) |
1234 | f.file->f_pos = pos; | |
9c225f26 | 1235 | fdput_pos(f); |
72ec3516 AV |
1236 | return ret; |
1237 | } | |
1238 | ||
f17d8b35 MT |
1239 | COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, |
1240 | const struct compat_iovec __user *, vec, | |
1241 | compat_ulong_t, vlen) | |
1242 | { | |
1243 | return do_compat_writev(fd, vec, vlen, 0); | |
1244 | } | |
1245 | ||
1246 | static long do_compat_pwritev64(unsigned long fd, | |
378a10f3 | 1247 | const struct compat_iovec __user *vec, |
f17d8b35 | 1248 | unsigned long vlen, loff_t pos, int flags) |
72ec3516 AV |
1249 | { |
1250 | struct fd f; | |
1251 | ssize_t ret; | |
1252 | ||
1253 | if (pos < 0) | |
1254 | return -EINVAL; | |
1255 | f = fdget(fd); | |
1256 | if (!f.file) | |
1257 | return -EBADF; | |
1258 | ret = -ESPIPE; | |
1259 | if (f.file->f_mode & FMODE_PWRITE) | |
f17d8b35 | 1260 | ret = compat_writev(f.file, vec, vlen, &pos, flags); |
72ec3516 AV |
1261 | fdput(f); |
1262 | return ret; | |
1263 | } | |
1264 | ||
378a10f3 HC |
1265 | #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64 |
1266 | COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, | |
1267 | const struct compat_iovec __user *,vec, | |
1268 | unsigned long, vlen, loff_t, pos) | |
1269 | { | |
f17d8b35 | 1270 | return do_compat_pwritev64(fd, vec, vlen, pos, 0); |
378a10f3 HC |
1271 | } |
1272 | #endif | |
1273 | ||
dfd948e3 | 1274 | COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, |
72ec3516 | 1275 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1276 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1277 | { |
1278 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 | 1279 | |
f17d8b35 | 1280 | return do_compat_pwritev64(fd, vec, vlen, pos, 0); |
72ec3516 | 1281 | } |
f17d8b35 | 1282 | |
3ebfd81f L |
1283 | #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64V2 |
1284 | COMPAT_SYSCALL_DEFINE5(pwritev64v2, unsigned long, fd, | |
1285 | const struct compat_iovec __user *,vec, | |
1286 | unsigned long, vlen, loff_t, pos, int, flags) | |
1287 | { | |
1288 | return do_compat_pwritev64(fd, vec, vlen, pos, flags); | |
1289 | } | |
1290 | #endif | |
1291 | ||
f17d8b35 MT |
1292 | COMPAT_SYSCALL_DEFINE6(pwritev2, compat_ulong_t, fd, |
1293 | const struct compat_iovec __user *,vec, | |
1294 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high, int, flags) | |
1295 | { | |
1296 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
1297 | ||
1298 | if (pos == -1) | |
1299 | return do_compat_writev(fd, vec, vlen, flags); | |
1300 | ||
1301 | return do_compat_pwritev64(fd, vec, vlen, pos, flags); | |
72ec3516 | 1302 | } |
f17d8b35 | 1303 | |
72ec3516 AV |
1304 | #endif |
1305 | ||
19f4fc3a AV |
1306 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, |
1307 | size_t count, loff_t max) | |
1da177e4 | 1308 | { |
2903ff01 AV |
1309 | struct fd in, out; |
1310 | struct inode *in_inode, *out_inode; | |
1da177e4 | 1311 | loff_t pos; |
7995bd28 | 1312 | loff_t out_pos; |
1da177e4 | 1313 | ssize_t retval; |
2903ff01 | 1314 | int fl; |
1da177e4 LT |
1315 | |
1316 | /* | |
1317 | * Get input file, and verify that it is ok.. | |
1318 | */ | |
1319 | retval = -EBADF; | |
2903ff01 AV |
1320 | in = fdget(in_fd); |
1321 | if (!in.file) | |
1da177e4 | 1322 | goto out; |
2903ff01 | 1323 | if (!(in.file->f_mode & FMODE_READ)) |
1da177e4 | 1324 | goto fput_in; |
1da177e4 | 1325 | retval = -ESPIPE; |
7995bd28 AV |
1326 | if (!ppos) { |
1327 | pos = in.file->f_pos; | |
1328 | } else { | |
1329 | pos = *ppos; | |
2903ff01 | 1330 | if (!(in.file->f_mode & FMODE_PREAD)) |
1da177e4 | 1331 | goto fput_in; |
7995bd28 AV |
1332 | } |
1333 | retval = rw_verify_area(READ, in.file, &pos, count); | |
e28cc715 | 1334 | if (retval < 0) |
1da177e4 | 1335 | goto fput_in; |
bc61384d AV |
1336 | if (count > MAX_RW_COUNT) |
1337 | count = MAX_RW_COUNT; | |
1da177e4 | 1338 | |
1da177e4 LT |
1339 | /* |
1340 | * Get output file, and verify that it is ok.. | |
1341 | */ | |
1342 | retval = -EBADF; | |
2903ff01 AV |
1343 | out = fdget(out_fd); |
1344 | if (!out.file) | |
1da177e4 | 1345 | goto fput_in; |
2903ff01 | 1346 | if (!(out.file->f_mode & FMODE_WRITE)) |
1da177e4 LT |
1347 | goto fput_out; |
1348 | retval = -EINVAL; | |
496ad9aa AV |
1349 | in_inode = file_inode(in.file); |
1350 | out_inode = file_inode(out.file); | |
7995bd28 AV |
1351 | out_pos = out.file->f_pos; |
1352 | retval = rw_verify_area(WRITE, out.file, &out_pos, count); | |
e28cc715 | 1353 | if (retval < 0) |
1da177e4 LT |
1354 | goto fput_out; |
1355 | ||
1da177e4 LT |
1356 | if (!max) |
1357 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); | |
1358 | ||
1da177e4 LT |
1359 | if (unlikely(pos + count > max)) { |
1360 | retval = -EOVERFLOW; | |
1361 | if (pos >= max) | |
1362 | goto fput_out; | |
1363 | count = max - pos; | |
1364 | } | |
1365 | ||
d96e6e71 | 1366 | fl = 0; |
534f2aaa | 1367 | #if 0 |
d96e6e71 JA |
1368 | /* |
1369 | * We need to debate whether we can enable this or not. The | |
1370 | * man page documents EAGAIN return for the output at least, | |
1371 | * and the application is arguably buggy if it doesn't expect | |
1372 | * EAGAIN on a non-blocking file descriptor. | |
1373 | */ | |
2903ff01 | 1374 | if (in.file->f_flags & O_NONBLOCK) |
d96e6e71 | 1375 | fl = SPLICE_F_NONBLOCK; |
534f2aaa | 1376 | #endif |
50cd2c57 | 1377 | file_start_write(out.file); |
7995bd28 | 1378 | retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl); |
50cd2c57 | 1379 | file_end_write(out.file); |
1da177e4 LT |
1380 | |
1381 | if (retval > 0) { | |
4b98d11b AD |
1382 | add_rchar(current, retval); |
1383 | add_wchar(current, retval); | |
a68c2f12 SW |
1384 | fsnotify_access(in.file); |
1385 | fsnotify_modify(out.file); | |
7995bd28 AV |
1386 | out.file->f_pos = out_pos; |
1387 | if (ppos) | |
1388 | *ppos = pos; | |
1389 | else | |
1390 | in.file->f_pos = pos; | |
1da177e4 | 1391 | } |
1da177e4 | 1392 | |
4b98d11b AD |
1393 | inc_syscr(current); |
1394 | inc_syscw(current); | |
7995bd28 | 1395 | if (pos > max) |
1da177e4 LT |
1396 | retval = -EOVERFLOW; |
1397 | ||
1398 | fput_out: | |
2903ff01 | 1399 | fdput(out); |
1da177e4 | 1400 | fput_in: |
2903ff01 | 1401 | fdput(in); |
1da177e4 LT |
1402 | out: |
1403 | return retval; | |
1404 | } | |
1405 | ||
002c8976 | 1406 | SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count) |
1da177e4 LT |
1407 | { |
1408 | loff_t pos; | |
1409 | off_t off; | |
1410 | ssize_t ret; | |
1411 | ||
1412 | if (offset) { | |
1413 | if (unlikely(get_user(off, offset))) | |
1414 | return -EFAULT; | |
1415 | pos = off; | |
1416 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1417 | if (unlikely(put_user(pos, offset))) | |
1418 | return -EFAULT; | |
1419 | return ret; | |
1420 | } | |
1421 | ||
1422 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1423 | } | |
1424 | ||
002c8976 | 1425 | SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count) |
1da177e4 LT |
1426 | { |
1427 | loff_t pos; | |
1428 | ssize_t ret; | |
1429 | ||
1430 | if (offset) { | |
1431 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1432 | return -EFAULT; | |
1433 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1434 | if (unlikely(put_user(pos, offset))) | |
1435 | return -EFAULT; | |
1436 | return ret; | |
1437 | } | |
1438 | ||
1439 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1440 | } | |
19f4fc3a AV |
1441 | |
1442 | #ifdef CONFIG_COMPAT | |
1443 | COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, | |
1444 | compat_off_t __user *, offset, compat_size_t, count) | |
1445 | { | |
1446 | loff_t pos; | |
1447 | off_t off; | |
1448 | ssize_t ret; | |
1449 | ||
1450 | if (offset) { | |
1451 | if (unlikely(get_user(off, offset))) | |
1452 | return -EFAULT; | |
1453 | pos = off; | |
1454 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1455 | if (unlikely(put_user(pos, offset))) | |
1456 | return -EFAULT; | |
1457 | return ret; | |
1458 | } | |
1459 | ||
1460 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1461 | } | |
1462 | ||
1463 | COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, | |
1464 | compat_loff_t __user *, offset, compat_size_t, count) | |
1465 | { | |
1466 | loff_t pos; | |
1467 | ssize_t ret; | |
1468 | ||
1469 | if (offset) { | |
1470 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1471 | return -EFAULT; | |
1472 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1473 | if (unlikely(put_user(pos, offset))) | |
1474 | return -EFAULT; | |
1475 | return ret; | |
1476 | } | |
1477 | ||
1478 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1479 | } | |
1480 | #endif | |
29732938 ZB |
1481 | |
1482 | /* | |
1483 | * copy_file_range() differs from regular file read and write in that it | |
1484 | * specifically allows return partial success. When it does so is up to | |
1485 | * the copy_file_range method. | |
1486 | */ | |
1487 | ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, | |
1488 | struct file *file_out, loff_t pos_out, | |
1489 | size_t len, unsigned int flags) | |
1490 | { | |
1491 | struct inode *inode_in = file_inode(file_in); | |
1492 | struct inode *inode_out = file_inode(file_out); | |
1493 | ssize_t ret; | |
1494 | ||
1495 | if (flags != 0) | |
1496 | return -EINVAL; | |
1497 | ||
11cbfb10 AG |
1498 | if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) |
1499 | return -EISDIR; | |
1500 | if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) | |
1501 | return -EINVAL; | |
1502 | ||
29732938 | 1503 | ret = rw_verify_area(READ, file_in, &pos_in, len); |
bc61384d AV |
1504 | if (unlikely(ret)) |
1505 | return ret; | |
1506 | ||
1507 | ret = rw_verify_area(WRITE, file_out, &pos_out, len); | |
1508 | if (unlikely(ret)) | |
29732938 ZB |
1509 | return ret; |
1510 | ||
1511 | if (!(file_in->f_mode & FMODE_READ) || | |
1512 | !(file_out->f_mode & FMODE_WRITE) || | |
eac70053 | 1513 | (file_out->f_flags & O_APPEND)) |
29732938 ZB |
1514 | return -EBADF; |
1515 | ||
1516 | /* this could be relaxed once a method supports cross-fs copies */ | |
1517 | if (inode_in->i_sb != inode_out->i_sb) | |
1518 | return -EXDEV; | |
1519 | ||
1520 | if (len == 0) | |
1521 | return 0; | |
1522 | ||
bfe219d3 | 1523 | file_start_write(file_out); |
29732938 | 1524 | |
a76b5b04 CH |
1525 | /* |
1526 | * Try cloning first, this is supported by more file systems, and | |
1527 | * more efficient if both clone and copy are supported (e.g. NFS). | |
1528 | */ | |
1529 | if (file_in->f_op->clone_file_range) { | |
1530 | ret = file_in->f_op->clone_file_range(file_in, pos_in, | |
1531 | file_out, pos_out, len); | |
1532 | if (ret == 0) { | |
1533 | ret = len; | |
1534 | goto done; | |
1535 | } | |
1536 | } | |
1537 | ||
1538 | if (file_out->f_op->copy_file_range) { | |
eac70053 AS |
1539 | ret = file_out->f_op->copy_file_range(file_in, pos_in, file_out, |
1540 | pos_out, len, flags); | |
a76b5b04 CH |
1541 | if (ret != -EOPNOTSUPP) |
1542 | goto done; | |
1543 | } | |
eac70053 | 1544 | |
a76b5b04 CH |
1545 | ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out, |
1546 | len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); | |
eac70053 | 1547 | |
a76b5b04 | 1548 | done: |
29732938 ZB |
1549 | if (ret > 0) { |
1550 | fsnotify_access(file_in); | |
1551 | add_rchar(current, ret); | |
1552 | fsnotify_modify(file_out); | |
1553 | add_wchar(current, ret); | |
1554 | } | |
a76b5b04 | 1555 | |
29732938 ZB |
1556 | inc_syscr(current); |
1557 | inc_syscw(current); | |
1558 | ||
bfe219d3 | 1559 | file_end_write(file_out); |
29732938 ZB |
1560 | |
1561 | return ret; | |
1562 | } | |
1563 | EXPORT_SYMBOL(vfs_copy_file_range); | |
1564 | ||
1565 | SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in, | |
1566 | int, fd_out, loff_t __user *, off_out, | |
1567 | size_t, len, unsigned int, flags) | |
1568 | { | |
1569 | loff_t pos_in; | |
1570 | loff_t pos_out; | |
1571 | struct fd f_in; | |
1572 | struct fd f_out; | |
1573 | ssize_t ret = -EBADF; | |
1574 | ||
1575 | f_in = fdget(fd_in); | |
1576 | if (!f_in.file) | |
1577 | goto out2; | |
1578 | ||
1579 | f_out = fdget(fd_out); | |
1580 | if (!f_out.file) | |
1581 | goto out1; | |
1582 | ||
1583 | ret = -EFAULT; | |
1584 | if (off_in) { | |
1585 | if (copy_from_user(&pos_in, off_in, sizeof(loff_t))) | |
1586 | goto out; | |
1587 | } else { | |
1588 | pos_in = f_in.file->f_pos; | |
1589 | } | |
1590 | ||
1591 | if (off_out) { | |
1592 | if (copy_from_user(&pos_out, off_out, sizeof(loff_t))) | |
1593 | goto out; | |
1594 | } else { | |
1595 | pos_out = f_out.file->f_pos; | |
1596 | } | |
1597 | ||
1598 | ret = vfs_copy_file_range(f_in.file, pos_in, f_out.file, pos_out, len, | |
1599 | flags); | |
1600 | if (ret > 0) { | |
1601 | pos_in += ret; | |
1602 | pos_out += ret; | |
1603 | ||
1604 | if (off_in) { | |
1605 | if (copy_to_user(off_in, &pos_in, sizeof(loff_t))) | |
1606 | ret = -EFAULT; | |
1607 | } else { | |
1608 | f_in.file->f_pos = pos_in; | |
1609 | } | |
1610 | ||
1611 | if (off_out) { | |
1612 | if (copy_to_user(off_out, &pos_out, sizeof(loff_t))) | |
1613 | ret = -EFAULT; | |
1614 | } else { | |
1615 | f_out.file->f_pos = pos_out; | |
1616 | } | |
1617 | } | |
1618 | ||
1619 | out: | |
1620 | fdput(f_out); | |
1621 | out1: | |
1622 | fdput(f_in); | |
1623 | out2: | |
1624 | return ret; | |
1625 | } | |
04b38d60 CH |
1626 | |
1627 | static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write) | |
1628 | { | |
1629 | struct inode *inode = file_inode(file); | |
1630 | ||
1631 | if (unlikely(pos < 0)) | |
1632 | return -EINVAL; | |
1633 | ||
1634 | if (unlikely((loff_t) (pos + len) < 0)) | |
1635 | return -EINVAL; | |
1636 | ||
1637 | if (unlikely(inode->i_flctx && mandatory_lock(inode))) { | |
1638 | loff_t end = len ? pos + len - 1 : OFFSET_MAX; | |
1639 | int retval; | |
1640 | ||
1641 | retval = locks_mandatory_area(inode, file, pos, end, | |
1642 | write ? F_WRLCK : F_RDLCK); | |
1643 | if (retval < 0) | |
1644 | return retval; | |
1645 | } | |
1646 | ||
1647 | return security_file_permission(file, write ? MAY_WRITE : MAY_READ); | |
1648 | } | |
1649 | ||
876bec6f DW |
1650 | /* |
1651 | * Check that the two inodes are eligible for cloning, the ranges make | |
1652 | * sense, and then flush all dirty data. Caller must ensure that the | |
1653 | * inodes have been locked against any other modifications. | |
22725ce4 DW |
1654 | * |
1655 | * Returns: 0 for "nothing to clone", 1 for "something to clone", or | |
1656 | * the usual negative error code. | |
876bec6f DW |
1657 | */ |
1658 | int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in, | |
1659 | struct inode *inode_out, loff_t pos_out, | |
1660 | u64 *len, bool is_dedupe) | |
1661 | { | |
1662 | loff_t bs = inode_out->i_sb->s_blocksize; | |
1663 | loff_t blen; | |
1664 | loff_t isize; | |
1665 | bool same_inode = (inode_in == inode_out); | |
1666 | int ret; | |
1667 | ||
1668 | /* Don't touch certain kinds of inodes */ | |
1669 | if (IS_IMMUTABLE(inode_out)) | |
1670 | return -EPERM; | |
1671 | ||
1672 | if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out)) | |
1673 | return -ETXTBSY; | |
1674 | ||
1675 | /* Don't reflink dirs, pipes, sockets... */ | |
1676 | if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) | |
1677 | return -EISDIR; | |
1678 | if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) | |
1679 | return -EINVAL; | |
1680 | ||
1681 | /* Are we going all the way to the end? */ | |
1682 | isize = i_size_read(inode_in); | |
22725ce4 | 1683 | if (isize == 0) |
876bec6f | 1684 | return 0; |
876bec6f DW |
1685 | |
1686 | /* Zero length dedupe exits immediately; reflink goes to EOF. */ | |
1687 | if (*len == 0) { | |
22725ce4 | 1688 | if (is_dedupe || pos_in == isize) |
876bec6f | 1689 | return 0; |
22725ce4 DW |
1690 | if (pos_in > isize) |
1691 | return -EINVAL; | |
876bec6f DW |
1692 | *len = isize - pos_in; |
1693 | } | |
1694 | ||
1695 | /* Ensure offsets don't wrap and the input is inside i_size */ | |
1696 | if (pos_in + *len < pos_in || pos_out + *len < pos_out || | |
1697 | pos_in + *len > isize) | |
1698 | return -EINVAL; | |
1699 | ||
1700 | /* Don't allow dedupe past EOF in the dest file */ | |
1701 | if (is_dedupe) { | |
1702 | loff_t disize; | |
1703 | ||
1704 | disize = i_size_read(inode_out); | |
1705 | if (pos_out >= disize || pos_out + *len > disize) | |
1706 | return -EINVAL; | |
1707 | } | |
1708 | ||
1709 | /* If we're linking to EOF, continue to the block boundary. */ | |
1710 | if (pos_in + *len == isize) | |
1711 | blen = ALIGN(isize, bs) - pos_in; | |
1712 | else | |
1713 | blen = *len; | |
1714 | ||
1715 | /* Only reflink if we're aligned to block boundaries */ | |
1716 | if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) || | |
1717 | !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs)) | |
1718 | return -EINVAL; | |
1719 | ||
1720 | /* Don't allow overlapped reflink within the same file */ | |
1721 | if (same_inode) { | |
1722 | if (pos_out + blen > pos_in && pos_out < pos_in + blen) | |
1723 | return -EINVAL; | |
1724 | } | |
1725 | ||
1726 | /* Wait for the completion of any pending IOs on both files */ | |
1727 | inode_dio_wait(inode_in); | |
1728 | if (!same_inode) | |
1729 | inode_dio_wait(inode_out); | |
1730 | ||
1731 | ret = filemap_write_and_wait_range(inode_in->i_mapping, | |
1732 | pos_in, pos_in + *len - 1); | |
1733 | if (ret) | |
1734 | return ret; | |
1735 | ||
1736 | ret = filemap_write_and_wait_range(inode_out->i_mapping, | |
1737 | pos_out, pos_out + *len - 1); | |
1738 | if (ret) | |
1739 | return ret; | |
1740 | ||
1741 | /* | |
1742 | * Check that the extents are the same. | |
1743 | */ | |
1744 | if (is_dedupe) { | |
1745 | bool is_same = false; | |
1746 | ||
1747 | ret = vfs_dedupe_file_range_compare(inode_in, pos_in, | |
1748 | inode_out, pos_out, *len, &is_same); | |
1749 | if (ret) | |
1750 | return ret; | |
1751 | if (!is_same) | |
1752 | return -EBADE; | |
1753 | } | |
1754 | ||
22725ce4 | 1755 | return 1; |
876bec6f DW |
1756 | } |
1757 | EXPORT_SYMBOL(vfs_clone_file_prep_inodes); | |
1758 | ||
04b38d60 CH |
1759 | int vfs_clone_file_range(struct file *file_in, loff_t pos_in, |
1760 | struct file *file_out, loff_t pos_out, u64 len) | |
1761 | { | |
1762 | struct inode *inode_in = file_inode(file_in); | |
1763 | struct inode *inode_out = file_inode(file_out); | |
1764 | int ret; | |
1765 | ||
b335e9d9 AG |
1766 | if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) |
1767 | return -EISDIR; | |
1768 | if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) | |
1769 | return -EINVAL; | |
1770 | ||
913b86e9 AG |
1771 | /* |
1772 | * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on | |
1773 | * the same mount. Practically, they only need to be on the same file | |
1774 | * system. | |
1775 | */ | |
1776 | if (inode_in->i_sb != inode_out->i_sb) | |
04b38d60 CH |
1777 | return -EXDEV; |
1778 | ||
04b38d60 CH |
1779 | if (!(file_in->f_mode & FMODE_READ) || |
1780 | !(file_out->f_mode & FMODE_WRITE) || | |
0fcbf996 | 1781 | (file_out->f_flags & O_APPEND)) |
04b38d60 CH |
1782 | return -EBADF; |
1783 | ||
0fcbf996 CH |
1784 | if (!file_in->f_op->clone_file_range) |
1785 | return -EOPNOTSUPP; | |
1786 | ||
04b38d60 CH |
1787 | ret = clone_verify_area(file_in, pos_in, len, false); |
1788 | if (ret) | |
1789 | return ret; | |
1790 | ||
1791 | ret = clone_verify_area(file_out, pos_out, len, true); | |
1792 | if (ret) | |
1793 | return ret; | |
1794 | ||
1795 | if (pos_in + len > i_size_read(inode_in)) | |
1796 | return -EINVAL; | |
1797 | ||
04b38d60 CH |
1798 | ret = file_in->f_op->clone_file_range(file_in, pos_in, |
1799 | file_out, pos_out, len); | |
1800 | if (!ret) { | |
1801 | fsnotify_access(file_in); | |
1802 | fsnotify_modify(file_out); | |
1803 | } | |
1804 | ||
04b38d60 CH |
1805 | return ret; |
1806 | } | |
1807 | EXPORT_SYMBOL(vfs_clone_file_range); | |
54dbc151 | 1808 | |
876bec6f DW |
1809 | /* |
1810 | * Read a page's worth of file data into the page cache. Return the page | |
1811 | * locked. | |
1812 | */ | |
1813 | static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset) | |
1814 | { | |
1815 | struct address_space *mapping; | |
1816 | struct page *page; | |
1817 | pgoff_t n; | |
1818 | ||
1819 | n = offset >> PAGE_SHIFT; | |
1820 | mapping = inode->i_mapping; | |
1821 | page = read_mapping_page(mapping, n, NULL); | |
1822 | if (IS_ERR(page)) | |
1823 | return page; | |
1824 | if (!PageUptodate(page)) { | |
1825 | put_page(page); | |
1826 | return ERR_PTR(-EIO); | |
1827 | } | |
1828 | lock_page(page); | |
1829 | return page; | |
1830 | } | |
1831 | ||
1832 | /* | |
1833 | * Compare extents of two files to see if they are the same. | |
1834 | * Caller must have locked both inodes to prevent write races. | |
1835 | */ | |
1836 | int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, | |
1837 | struct inode *dest, loff_t destoff, | |
1838 | loff_t len, bool *is_same) | |
1839 | { | |
1840 | loff_t src_poff; | |
1841 | loff_t dest_poff; | |
1842 | void *src_addr; | |
1843 | void *dest_addr; | |
1844 | struct page *src_page; | |
1845 | struct page *dest_page; | |
1846 | loff_t cmp_len; | |
1847 | bool same; | |
1848 | int error; | |
1849 | ||
1850 | error = -EINVAL; | |
1851 | same = true; | |
1852 | while (len) { | |
1853 | src_poff = srcoff & (PAGE_SIZE - 1); | |
1854 | dest_poff = destoff & (PAGE_SIZE - 1); | |
1855 | cmp_len = min(PAGE_SIZE - src_poff, | |
1856 | PAGE_SIZE - dest_poff); | |
1857 | cmp_len = min(cmp_len, len); | |
1858 | if (cmp_len <= 0) | |
1859 | goto out_error; | |
1860 | ||
1861 | src_page = vfs_dedupe_get_page(src, srcoff); | |
1862 | if (IS_ERR(src_page)) { | |
1863 | error = PTR_ERR(src_page); | |
1864 | goto out_error; | |
1865 | } | |
1866 | dest_page = vfs_dedupe_get_page(dest, destoff); | |
1867 | if (IS_ERR(dest_page)) { | |
1868 | error = PTR_ERR(dest_page); | |
1869 | unlock_page(src_page); | |
1870 | put_page(src_page); | |
1871 | goto out_error; | |
1872 | } | |
1873 | src_addr = kmap_atomic(src_page); | |
1874 | dest_addr = kmap_atomic(dest_page); | |
1875 | ||
1876 | flush_dcache_page(src_page); | |
1877 | flush_dcache_page(dest_page); | |
1878 | ||
1879 | if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) | |
1880 | same = false; | |
1881 | ||
1882 | kunmap_atomic(dest_addr); | |
1883 | kunmap_atomic(src_addr); | |
1884 | unlock_page(dest_page); | |
1885 | unlock_page(src_page); | |
1886 | put_page(dest_page); | |
1887 | put_page(src_page); | |
1888 | ||
1889 | if (!same) | |
1890 | break; | |
1891 | ||
1892 | srcoff += cmp_len; | |
1893 | destoff += cmp_len; | |
1894 | len -= cmp_len; | |
1895 | } | |
1896 | ||
1897 | *is_same = same; | |
1898 | return 0; | |
1899 | ||
1900 | out_error: | |
1901 | return error; | |
1902 | } | |
1903 | EXPORT_SYMBOL(vfs_dedupe_file_range_compare); | |
1904 | ||
54dbc151 DW |
1905 | int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) |
1906 | { | |
1907 | struct file_dedupe_range_info *info; | |
1908 | struct inode *src = file_inode(file); | |
1909 | u64 off; | |
1910 | u64 len; | |
1911 | int i; | |
1912 | int ret; | |
1913 | bool is_admin = capable(CAP_SYS_ADMIN); | |
1914 | u16 count = same->dest_count; | |
1915 | struct file *dst_file; | |
1916 | loff_t dst_off; | |
1917 | ssize_t deduped; | |
1918 | ||
1919 | if (!(file->f_mode & FMODE_READ)) | |
1920 | return -EINVAL; | |
1921 | ||
1922 | if (same->reserved1 || same->reserved2) | |
1923 | return -EINVAL; | |
1924 | ||
1925 | off = same->src_offset; | |
1926 | len = same->src_length; | |
1927 | ||
1928 | ret = -EISDIR; | |
1929 | if (S_ISDIR(src->i_mode)) | |
1930 | goto out; | |
1931 | ||
1932 | ret = -EINVAL; | |
1933 | if (!S_ISREG(src->i_mode)) | |
1934 | goto out; | |
1935 | ||
1936 | ret = clone_verify_area(file, off, len, false); | |
1937 | if (ret < 0) | |
1938 | goto out; | |
1939 | ret = 0; | |
1940 | ||
22725ce4 DW |
1941 | if (off + len > i_size_read(src)) |
1942 | return -EINVAL; | |
1943 | ||
54dbc151 DW |
1944 | /* pre-format output fields to sane values */ |
1945 | for (i = 0; i < count; i++) { | |
1946 | same->info[i].bytes_deduped = 0ULL; | |
1947 | same->info[i].status = FILE_DEDUPE_RANGE_SAME; | |
1948 | } | |
1949 | ||
1950 | for (i = 0, info = same->info; i < count; i++, info++) { | |
1951 | struct inode *dst; | |
1952 | struct fd dst_fd = fdget(info->dest_fd); | |
1953 | ||
1954 | dst_file = dst_fd.file; | |
1955 | if (!dst_file) { | |
1956 | info->status = -EBADF; | |
1957 | goto next_loop; | |
1958 | } | |
1959 | dst = file_inode(dst_file); | |
1960 | ||
1961 | ret = mnt_want_write_file(dst_file); | |
1962 | if (ret) { | |
1963 | info->status = ret; | |
1964 | goto next_loop; | |
1965 | } | |
1966 | ||
1967 | dst_off = info->dest_offset; | |
1968 | ret = clone_verify_area(dst_file, dst_off, len, true); | |
1969 | if (ret < 0) { | |
1970 | info->status = ret; | |
1971 | goto next_file; | |
1972 | } | |
1973 | ret = 0; | |
1974 | ||
1975 | if (info->reserved) { | |
1976 | info->status = -EINVAL; | |
1977 | } else if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) { | |
1978 | info->status = -EINVAL; | |
1979 | } else if (file->f_path.mnt != dst_file->f_path.mnt) { | |
1980 | info->status = -EXDEV; | |
1981 | } else if (S_ISDIR(dst->i_mode)) { | |
1982 | info->status = -EISDIR; | |
1983 | } else if (dst_file->f_op->dedupe_file_range == NULL) { | |
1984 | info->status = -EINVAL; | |
1985 | } else { | |
1986 | deduped = dst_file->f_op->dedupe_file_range(file, off, | |
1987 | len, dst_file, | |
1988 | info->dest_offset); | |
1989 | if (deduped == -EBADE) | |
1990 | info->status = FILE_DEDUPE_RANGE_DIFFERS; | |
1991 | else if (deduped < 0) | |
1992 | info->status = deduped; | |
1993 | else | |
1994 | info->bytes_deduped += deduped; | |
1995 | } | |
1996 | ||
1997 | next_file: | |
1998 | mnt_drop_write_file(dst_file); | |
1999 | next_loop: | |
2000 | fdput(dst_fd); | |
e62e560f DW |
2001 | |
2002 | if (fatal_signal_pending(current)) | |
2003 | goto out; | |
54dbc151 DW |
2004 | } |
2005 | ||
2006 | out: | |
2007 | return ret; | |
2008 | } | |
2009 | EXPORT_SYMBOL(vfs_dedupe_file_range); |