Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/fs/read_write.c | |
4 | * | |
5 | * Copyright (C) 1991, 1992 Linus Torvalds | |
6 | */ | |
7 | ||
b12fb7f4 | 8 | #include <linux/slab.h> |
1da177e4 | 9 | #include <linux/stat.h> |
b12fb7f4 | 10 | #include <linux/sched/xacct.h> |
1da177e4 LT |
11 | #include <linux/fcntl.h> |
12 | #include <linux/file.h> | |
13 | #include <linux/uio.h> | |
0eeca283 | 14 | #include <linux/fsnotify.h> |
1da177e4 | 15 | #include <linux/security.h> |
630d9c47 | 16 | #include <linux/export.h> |
1da177e4 | 17 | #include <linux/syscalls.h> |
e28cc715 | 18 | #include <linux/pagemap.h> |
d6b29d7c | 19 | #include <linux/splice.h> |
561c6731 | 20 | #include <linux/compat.h> |
29732938 | 21 | #include <linux/mount.h> |
2feb55f8 | 22 | #include <linux/fs.h> |
06ae43f3 | 23 | #include "internal.h" |
1da177e4 | 24 | |
7c0f6ba6 | 25 | #include <linux/uaccess.h> |
1da177e4 LT |
26 | #include <asm/unistd.h> |
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 | ||
ddef7ed2 | 37 | static inline bool 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 | */ | |
fc46820b | 116 | if ((unsigned long long)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 | */ | |
fc46820b | 124 | if ((unsigned long long)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, | |
2feb55f8 | 186 | OFFSET_MAX, 0); |
b25472f9 AV |
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 | ||
bef17329 | 304 | static off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence) |
1da177e4 LT |
305 | { |
306 | off_t retval; | |
9c225f26 | 307 | struct fd f = fdget_pos(fd); |
2903ff01 AV |
308 | if (!f.file) |
309 | return -EBADF; | |
1da177e4 LT |
310 | |
311 | retval = -EINVAL; | |
965c8e59 AM |
312 | if (whence <= SEEK_MAX) { |
313 | loff_t res = vfs_llseek(f.file, offset, whence); | |
1da177e4 LT |
314 | retval = res; |
315 | if (res != (loff_t)retval) | |
316 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ | |
317 | } | |
9c225f26 | 318 | fdput_pos(f); |
1da177e4 LT |
319 | return retval; |
320 | } | |
321 | ||
76847e43 DB |
322 | SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence) |
323 | { | |
324 | return ksys_lseek(fd, offset, whence); | |
325 | } | |
326 | ||
561c6731 AV |
327 | #ifdef CONFIG_COMPAT |
328 | COMPAT_SYSCALL_DEFINE3(lseek, unsigned int, fd, compat_off_t, offset, unsigned int, whence) | |
329 | { | |
76847e43 | 330 | return ksys_lseek(fd, offset, whence); |
561c6731 AV |
331 | } |
332 | #endif | |
333 | ||
9e62ccec MS |
334 | #if !defined(CONFIG_64BIT) || defined(CONFIG_COMPAT) || \ |
335 | defined(__ARCH_WANT_SYS_LLSEEK) | |
003d7ab4 HC |
336 | SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, |
337 | unsigned long, offset_low, loff_t __user *, result, | |
965c8e59 | 338 | unsigned int, whence) |
1da177e4 LT |
339 | { |
340 | int retval; | |
d7a15f8d | 341 | struct fd f = fdget_pos(fd); |
1da177e4 | 342 | loff_t offset; |
1da177e4 | 343 | |
2903ff01 AV |
344 | if (!f.file) |
345 | return -EBADF; | |
1da177e4 LT |
346 | |
347 | retval = -EINVAL; | |
965c8e59 | 348 | if (whence > SEEK_MAX) |
1da177e4 LT |
349 | goto out_putf; |
350 | ||
2903ff01 | 351 | offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low, |
965c8e59 | 352 | whence); |
1da177e4 LT |
353 | |
354 | retval = (int)offset; | |
355 | if (offset >= 0) { | |
356 | retval = -EFAULT; | |
357 | if (!copy_to_user(result, &offset, sizeof(offset))) | |
358 | retval = 0; | |
359 | } | |
360 | out_putf: | |
d7a15f8d | 361 | fdput_pos(f); |
1da177e4 LT |
362 | return retval; |
363 | } | |
364 | #endif | |
365 | ||
68d70d03 | 366 | int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count) |
1da177e4 LT |
367 | { |
368 | struct inode *inode; | |
c43e259c | 369 | int retval = -EINVAL; |
1da177e4 | 370 | |
496ad9aa | 371 | inode = file_inode(file); |
e28cc715 | 372 | if (unlikely((ssize_t) count < 0)) |
c43e259c | 373 | return retval; |
1da177e4 | 374 | |
438ab720 KS |
375 | /* |
376 | * ranged mandatory locking does not apply to streams - it makes sense | |
377 | * only for files where position has a meaning. | |
378 | */ | |
379 | if (ppos) { | |
380 | loff_t pos = *ppos; | |
381 | ||
382 | if (unlikely(pos < 0)) { | |
383 | if (!unsigned_offsets(file)) | |
384 | return retval; | |
385 | if (count >= -pos) /* both values are in 0..LLONG_MAX */ | |
386 | return -EOVERFLOW; | |
387 | } else if (unlikely((loff_t) (pos + count) < 0)) { | |
388 | if (!unsigned_offsets(file)) | |
389 | return retval; | |
390 | } | |
391 | ||
392 | if (unlikely(inode->i_flctx && mandatory_lock(inode))) { | |
393 | retval = locks_mandatory_area(inode, file, pos, pos + count - 1, | |
394 | read_write == READ ? F_RDLCK : F_WRLCK); | |
395 | if (retval < 0) | |
396 | return retval; | |
397 | } | |
e28cc715 | 398 | } |
438ab720 | 399 | |
bc61384d | 400 | return security_file_permission(file, |
c43e259c | 401 | read_write == READ ? MAY_READ : MAY_WRITE); |
1da177e4 LT |
402 | } |
403 | ||
5d5d5689 | 404 | static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
293bc982 AV |
405 | { |
406 | struct iovec iov = { .iov_base = buf, .iov_len = len }; | |
407 | struct kiocb kiocb; | |
408 | struct iov_iter iter; | |
409 | ssize_t ret; | |
410 | ||
411 | init_sync_kiocb(&kiocb, filp); | |
438ab720 | 412 | kiocb.ki_pos = (ppos ? *ppos : 0); |
293bc982 AV |
413 | iov_iter_init(&iter, READ, &iov, 1, len); |
414 | ||
bb7462b6 | 415 | ret = call_read_iter(filp, &kiocb, &iter); |
599bd19b | 416 | BUG_ON(ret == -EIOCBQUEUED); |
438ab720 KS |
417 | if (ppos) |
418 | *ppos = kiocb.ki_pos; | |
293bc982 AV |
419 | return ret; |
420 | } | |
421 | ||
61a707c5 CH |
422 | ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos) |
423 | { | |
424 | mm_segment_t old_fs = get_fs(); | |
425 | ssize_t ret; | |
426 | ||
427 | if (WARN_ON_ONCE(!(file->f_mode & FMODE_READ))) | |
428 | return -EINVAL; | |
429 | if (!(file->f_mode & FMODE_CAN_READ)) | |
430 | return -EINVAL; | |
431 | ||
432 | if (count > MAX_RW_COUNT) | |
433 | count = MAX_RW_COUNT; | |
434 | set_fs(KERNEL_DS); | |
775802c0 CH |
435 | if (file->f_op->read) |
436 | ret = file->f_op->read(file, (void __user *)buf, count, pos); | |
437 | else if (file->f_op->read_iter) | |
438 | ret = new_sync_read(file, (void __user *)buf, count, pos); | |
439 | else | |
440 | ret = -EINVAL; | |
61a707c5 CH |
441 | set_fs(old_fs); |
442 | if (ret > 0) { | |
443 | fsnotify_access(file); | |
444 | add_rchar(current, ret); | |
445 | } | |
446 | inc_syscr(current); | |
447 | return ret; | |
448 | } | |
449 | ||
bdd1d2d3 | 450 | ssize_t kernel_read(struct file *file, void *buf, size_t count, loff_t *pos) |
c41fbad0 | 451 | { |
6209dd91 | 452 | ssize_t ret; |
c41fbad0 | 453 | |
6209dd91 CH |
454 | ret = rw_verify_area(READ, file, pos, count); |
455 | if (ret) | |
456 | return ret; | |
457 | return __kernel_read(file, buf, count, pos); | |
c41fbad0 CH |
458 | } |
459 | EXPORT_SYMBOL(kernel_read); | |
6fb5032e | 460 | |
1da177e4 LT |
461 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) |
462 | { | |
463 | ssize_t ret; | |
464 | ||
465 | if (!(file->f_mode & FMODE_READ)) | |
466 | return -EBADF; | |
7f7f25e8 | 467 | if (!(file->f_mode & FMODE_CAN_READ)) |
1da177e4 | 468 | return -EINVAL; |
96d4f267 | 469 | if (unlikely(!access_ok(buf, count))) |
1da177e4 LT |
470 | return -EFAULT; |
471 | ||
472 | ret = rw_verify_area(READ, file, pos, count); | |
775802c0 CH |
473 | if (ret) |
474 | return ret; | |
475 | if (count > MAX_RW_COUNT) | |
476 | count = MAX_RW_COUNT; | |
1da177e4 | 477 | |
775802c0 CH |
478 | if (file->f_op->read) |
479 | ret = file->f_op->read(file, buf, count, pos); | |
480 | else if (file->f_op->read_iter) | |
481 | ret = new_sync_read(file, buf, count, pos); | |
482 | else | |
483 | ret = -EINVAL; | |
484 | if (ret > 0) { | |
485 | fsnotify_access(file); | |
486 | add_rchar(current, ret); | |
487 | } | |
488 | inc_syscr(current); | |
1da177e4 LT |
489 | return ret; |
490 | } | |
491 | ||
5d5d5689 | 492 | static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) |
293bc982 AV |
493 | { |
494 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; | |
495 | struct kiocb kiocb; | |
496 | struct iov_iter iter; | |
497 | ssize_t ret; | |
498 | ||
499 | init_sync_kiocb(&kiocb, filp); | |
438ab720 | 500 | kiocb.ki_pos = (ppos ? *ppos : 0); |
293bc982 AV |
501 | iov_iter_init(&iter, WRITE, &iov, 1, len); |
502 | ||
bb7462b6 | 503 | ret = call_write_iter(filp, &kiocb, &iter); |
599bd19b | 504 | BUG_ON(ret == -EIOCBQUEUED); |
438ab720 | 505 | if (ret > 0 && ppos) |
f765b134 | 506 | *ppos = kiocb.ki_pos; |
293bc982 AV |
507 | return ret; |
508 | } | |
509 | ||
81238b2c | 510 | /* caller is responsible for file_start_write/file_end_write */ |
73e18f7c | 511 | ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t *pos) |
06ae43f3 AV |
512 | { |
513 | mm_segment_t old_fs; | |
514 | const char __user *p; | |
515 | ssize_t ret; | |
516 | ||
a01ac27b CH |
517 | if (WARN_ON_ONCE(!(file->f_mode & FMODE_WRITE))) |
518 | return -EBADF; | |
7f7f25e8 | 519 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
3e84f48e AV |
520 | return -EINVAL; |
521 | ||
06ae43f3 | 522 | old_fs = get_fs(); |
736706be | 523 | set_fs(KERNEL_DS); |
06ae43f3 AV |
524 | p = (__force const char __user *)buf; |
525 | if (count > MAX_RW_COUNT) | |
526 | count = MAX_RW_COUNT; | |
53ad8626 CH |
527 | if (file->f_op->write) |
528 | ret = file->f_op->write(file, p, count, pos); | |
529 | else if (file->f_op->write_iter) | |
530 | ret = new_sync_write(file, p, count, pos); | |
531 | else | |
532 | ret = -EINVAL; | |
06ae43f3 AV |
533 | set_fs(old_fs); |
534 | if (ret > 0) { | |
535 | fsnotify_modify(file); | |
536 | add_wchar(current, ret); | |
537 | } | |
538 | inc_syscw(current); | |
539 | return ret; | |
540 | } | |
90fb7027 LT |
541 | /* |
542 | * This "EXPORT_SYMBOL_GPL()" is more of a "EXPORT_SYMBOL_DONTUSE()", | |
543 | * but autofs is one of the few internal kernel users that actually | |
544 | * wants this _and_ can be built as a module. So we need to export | |
545 | * this symbol for autofs, even though it really isn't appropriate | |
546 | * for any other kernel modules. | |
547 | */ | |
548 | EXPORT_SYMBOL_GPL(__kernel_write); | |
2ec3a12a | 549 | |
e13ec939 CH |
550 | ssize_t kernel_write(struct file *file, const void *buf, size_t count, |
551 | loff_t *pos) | |
ac452aca | 552 | { |
81238b2c | 553 | ssize_t ret; |
ac452aca | 554 | |
81238b2c CH |
555 | ret = rw_verify_area(WRITE, file, pos, count); |
556 | if (ret) | |
557 | return ret; | |
ac452aca | 558 | |
81238b2c CH |
559 | file_start_write(file); |
560 | ret = __kernel_write(file, buf, count, pos); | |
561 | file_end_write(file); | |
562 | return ret; | |
ac452aca CH |
563 | } |
564 | EXPORT_SYMBOL(kernel_write); | |
565 | ||
1da177e4 LT |
566 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
567 | { | |
568 | ssize_t ret; | |
569 | ||
570 | if (!(file->f_mode & FMODE_WRITE)) | |
571 | return -EBADF; | |
7f7f25e8 | 572 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
1da177e4 | 573 | return -EINVAL; |
96d4f267 | 574 | if (unlikely(!access_ok(buf, count))) |
1da177e4 LT |
575 | return -EFAULT; |
576 | ||
577 | ret = rw_verify_area(WRITE, file, pos, count); | |
53ad8626 CH |
578 | if (ret) |
579 | return ret; | |
580 | if (count > MAX_RW_COUNT) | |
581 | count = MAX_RW_COUNT; | |
582 | file_start_write(file); | |
583 | if (file->f_op->write) | |
584 | ret = file->f_op->write(file, buf, count, pos); | |
585 | else if (file->f_op->write_iter) | |
586 | ret = new_sync_write(file, buf, count, pos); | |
587 | else | |
588 | ret = -EINVAL; | |
589 | if (ret > 0) { | |
590 | fsnotify_modify(file); | |
591 | add_wchar(current, ret); | |
1da177e4 | 592 | } |
53ad8626 CH |
593 | inc_syscw(current); |
594 | file_end_write(file); | |
1da177e4 LT |
595 | return ret; |
596 | } | |
597 | ||
438ab720 KS |
598 | /* file_ppos returns &file->f_pos or NULL if file is stream */ |
599 | static inline loff_t *file_ppos(struct file *file) | |
1da177e4 | 600 | { |
438ab720 | 601 | return file->f_mode & FMODE_STREAM ? NULL : &file->f_pos; |
1da177e4 LT |
602 | } |
603 | ||
3ce4a7bf | 604 | ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count) |
1da177e4 | 605 | { |
9c225f26 | 606 | struct fd f = fdget_pos(fd); |
1da177e4 | 607 | ssize_t ret = -EBADF; |
1da177e4 | 608 | |
2903ff01 | 609 | if (f.file) { |
438ab720 KS |
610 | loff_t pos, *ppos = file_ppos(f.file); |
611 | if (ppos) { | |
612 | pos = *ppos; | |
613 | ppos = &pos; | |
614 | } | |
615 | ret = vfs_read(f.file, buf, count, ppos); | |
616 | if (ret >= 0 && ppos) | |
617 | f.file->f_pos = pos; | |
9c225f26 | 618 | fdput_pos(f); |
1da177e4 | 619 | } |
1da177e4 LT |
620 | return ret; |
621 | } | |
1da177e4 | 622 | |
3ce4a7bf DB |
623 | SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) |
624 | { | |
625 | return ksys_read(fd, buf, count); | |
626 | } | |
627 | ||
e7a3e8b2 | 628 | ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count) |
1da177e4 | 629 | { |
9c225f26 | 630 | struct fd f = fdget_pos(fd); |
1da177e4 | 631 | ssize_t ret = -EBADF; |
1da177e4 | 632 | |
2903ff01 | 633 | if (f.file) { |
438ab720 KS |
634 | loff_t pos, *ppos = file_ppos(f.file); |
635 | if (ppos) { | |
636 | pos = *ppos; | |
637 | ppos = &pos; | |
638 | } | |
639 | ret = vfs_write(f.file, buf, count, ppos); | |
640 | if (ret >= 0 && ppos) | |
641 | f.file->f_pos = pos; | |
9c225f26 | 642 | fdput_pos(f); |
1da177e4 LT |
643 | } |
644 | ||
645 | return ret; | |
646 | } | |
647 | ||
e7a3e8b2 DB |
648 | SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, |
649 | size_t, count) | |
650 | { | |
651 | return ksys_write(fd, buf, count); | |
652 | } | |
653 | ||
36028d5d DB |
654 | ssize_t ksys_pread64(unsigned int fd, char __user *buf, size_t count, |
655 | loff_t pos) | |
1da177e4 | 656 | { |
2903ff01 | 657 | struct fd f; |
1da177e4 | 658 | ssize_t ret = -EBADF; |
1da177e4 LT |
659 | |
660 | if (pos < 0) | |
661 | return -EINVAL; | |
662 | ||
2903ff01 AV |
663 | f = fdget(fd); |
664 | if (f.file) { | |
1da177e4 | 665 | ret = -ESPIPE; |
2903ff01 AV |
666 | if (f.file->f_mode & FMODE_PREAD) |
667 | ret = vfs_read(f.file, buf, count, &pos); | |
668 | fdput(f); | |
1da177e4 LT |
669 | } |
670 | ||
671 | return ret; | |
672 | } | |
673 | ||
36028d5d DB |
674 | SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, |
675 | size_t, count, loff_t, pos) | |
676 | { | |
677 | return ksys_pread64(fd, buf, count, pos); | |
678 | } | |
679 | ||
680 | ssize_t ksys_pwrite64(unsigned int fd, const char __user *buf, | |
681 | size_t count, loff_t pos) | |
1da177e4 | 682 | { |
2903ff01 | 683 | struct fd f; |
1da177e4 | 684 | ssize_t ret = -EBADF; |
1da177e4 LT |
685 | |
686 | if (pos < 0) | |
687 | return -EINVAL; | |
688 | ||
2903ff01 AV |
689 | f = fdget(fd); |
690 | if (f.file) { | |
1da177e4 | 691 | ret = -ESPIPE; |
2903ff01 AV |
692 | if (f.file->f_mode & FMODE_PWRITE) |
693 | ret = vfs_write(f.file, buf, count, &pos); | |
694 | fdput(f); | |
1da177e4 LT |
695 | } |
696 | ||
697 | return ret; | |
698 | } | |
699 | ||
36028d5d DB |
700 | SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, |
701 | size_t, count, loff_t, pos) | |
702 | { | |
703 | return ksys_pwrite64(fd, buf, count, pos); | |
704 | } | |
705 | ||
ac15ac06 | 706 | static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, |
ddef7ed2 | 707 | loff_t *ppos, int type, rwf_t flags) |
293bc982 AV |
708 | { |
709 | struct kiocb kiocb; | |
293bc982 AV |
710 | ssize_t ret; |
711 | ||
712 | init_sync_kiocb(&kiocb, filp); | |
fdd2f5b7 GR |
713 | ret = kiocb_set_rw_flags(&kiocb, flags); |
714 | if (ret) | |
715 | return ret; | |
438ab720 | 716 | kiocb.ki_pos = (ppos ? *ppos : 0); |
293bc982 | 717 | |
0f78d06a | 718 | if (type == READ) |
bb7462b6 | 719 | ret = call_read_iter(filp, &kiocb, iter); |
0f78d06a | 720 | else |
bb7462b6 | 721 | ret = call_write_iter(filp, &kiocb, iter); |
599bd19b | 722 | BUG_ON(ret == -EIOCBQUEUED); |
438ab720 KS |
723 | if (ppos) |
724 | *ppos = kiocb.ki_pos; | |
293bc982 AV |
725 | return ret; |
726 | } | |
727 | ||
ee0b3e67 | 728 | /* Do it by hand, with file-ops */ |
ac15ac06 | 729 | static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, |
ddef7ed2 | 730 | loff_t *ppos, int type, rwf_t flags) |
ee0b3e67 | 731 | { |
ee0b3e67 BP |
732 | ssize_t ret = 0; |
733 | ||
97be7ebe | 734 | if (flags & ~RWF_HIPRI) |
793b80ef CH |
735 | return -EOPNOTSUPP; |
736 | ||
ac15ac06 AV |
737 | while (iov_iter_count(iter)) { |
738 | struct iovec iovec = iov_iter_iovec(iter); | |
ee0b3e67 BP |
739 | ssize_t nr; |
740 | ||
0f78d06a MS |
741 | if (type == READ) { |
742 | nr = filp->f_op->read(filp, iovec.iov_base, | |
743 | iovec.iov_len, ppos); | |
744 | } else { | |
745 | nr = filp->f_op->write(filp, iovec.iov_base, | |
746 | iovec.iov_len, ppos); | |
747 | } | |
ee0b3e67 BP |
748 | |
749 | if (nr < 0) { | |
750 | if (!ret) | |
751 | ret = nr; | |
752 | break; | |
753 | } | |
754 | ret += nr; | |
ac15ac06 | 755 | if (nr != iovec.iov_len) |
ee0b3e67 | 756 | break; |
ac15ac06 | 757 | iov_iter_advance(iter, nr); |
ee0b3e67 BP |
758 | } |
759 | ||
760 | return ret; | |
761 | } | |
762 | ||
19c73586 | 763 | static ssize_t do_iter_read(struct file *file, struct iov_iter *iter, |
ddef7ed2 | 764 | loff_t *pos, rwf_t flags) |
1da177e4 | 765 | { |
1da177e4 | 766 | size_t tot_len; |
7687a7a4 | 767 | ssize_t ret = 0; |
1da177e4 | 768 | |
edab5fe3 CH |
769 | if (!(file->f_mode & FMODE_READ)) |
770 | return -EBADF; | |
771 | if (!(file->f_mode & FMODE_CAN_READ)) | |
772 | return -EINVAL; | |
773 | ||
7687a7a4 | 774 | tot_len = iov_iter_count(iter); |
0504c074 AV |
775 | if (!tot_len) |
776 | goto out; | |
19c73586 | 777 | ret = rw_verify_area(READ, file, pos, tot_len); |
e28cc715 | 778 | if (ret < 0) |
19c73586 | 779 | return ret; |
1da177e4 | 780 | |
19c73586 CH |
781 | if (file->f_op->read_iter) |
782 | ret = do_iter_readv_writev(file, iter, pos, READ, flags); | |
ee0b3e67 | 783 | else |
19c73586 | 784 | ret = do_loop_readv_writev(file, iter, pos, READ, flags); |
1da177e4 | 785 | out: |
19c73586 CH |
786 | if (ret >= 0) |
787 | fsnotify_access(file); | |
1da177e4 | 788 | return ret; |
1da177e4 LT |
789 | } |
790 | ||
5dcdc43e JX |
791 | ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb, |
792 | struct iov_iter *iter) | |
793 | { | |
794 | size_t tot_len; | |
795 | ssize_t ret = 0; | |
796 | ||
797 | if (!file->f_op->read_iter) | |
798 | return -EINVAL; | |
799 | if (!(file->f_mode & FMODE_READ)) | |
800 | return -EBADF; | |
801 | if (!(file->f_mode & FMODE_CAN_READ)) | |
802 | return -EINVAL; | |
803 | ||
804 | tot_len = iov_iter_count(iter); | |
805 | if (!tot_len) | |
806 | goto out; | |
807 | ret = rw_verify_area(READ, file, &iocb->ki_pos, tot_len); | |
808 | if (ret < 0) | |
809 | return ret; | |
810 | ||
811 | ret = call_read_iter(file, iocb, iter); | |
812 | out: | |
813 | if (ret >= 0) | |
814 | fsnotify_access(file); | |
815 | return ret; | |
816 | } | |
817 | EXPORT_SYMBOL(vfs_iocb_iter_read); | |
818 | ||
18e9710e | 819 | ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos, |
ddef7ed2 | 820 | rwf_t flags) |
7687a7a4 | 821 | { |
18e9710e CH |
822 | if (!file->f_op->read_iter) |
823 | return -EINVAL; | |
824 | return do_iter_read(file, iter, ppos, flags); | |
825 | } | |
826 | EXPORT_SYMBOL(vfs_iter_read); | |
7687a7a4 | 827 | |
19c73586 | 828 | static ssize_t do_iter_write(struct file *file, struct iov_iter *iter, |
ddef7ed2 | 829 | loff_t *pos, rwf_t flags) |
19c73586 CH |
830 | { |
831 | size_t tot_len; | |
832 | ssize_t ret = 0; | |
03d95eb2 | 833 | |
edab5fe3 CH |
834 | if (!(file->f_mode & FMODE_WRITE)) |
835 | return -EBADF; | |
836 | if (!(file->f_mode & FMODE_CAN_WRITE)) | |
837 | return -EINVAL; | |
838 | ||
19c73586 CH |
839 | tot_len = iov_iter_count(iter); |
840 | if (!tot_len) | |
841 | return 0; | |
842 | ret = rw_verify_area(WRITE, file, pos, tot_len); | |
7687a7a4 MS |
843 | if (ret < 0) |
844 | return ret; | |
845 | ||
19c73586 CH |
846 | if (file->f_op->write_iter) |
847 | ret = do_iter_readv_writev(file, iter, pos, WRITE, flags); | |
848 | else | |
849 | ret = do_loop_readv_writev(file, iter, pos, WRITE, flags); | |
19c73586 CH |
850 | if (ret > 0) |
851 | fsnotify_modify(file); | |
7687a7a4 MS |
852 | return ret; |
853 | } | |
854 | ||
5dcdc43e JX |
855 | ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb, |
856 | struct iov_iter *iter) | |
857 | { | |
858 | size_t tot_len; | |
859 | ssize_t ret = 0; | |
860 | ||
861 | if (!file->f_op->write_iter) | |
862 | return -EINVAL; | |
863 | if (!(file->f_mode & FMODE_WRITE)) | |
864 | return -EBADF; | |
865 | if (!(file->f_mode & FMODE_CAN_WRITE)) | |
866 | return -EINVAL; | |
867 | ||
868 | tot_len = iov_iter_count(iter); | |
869 | if (!tot_len) | |
870 | return 0; | |
871 | ret = rw_verify_area(WRITE, file, &iocb->ki_pos, tot_len); | |
872 | if (ret < 0) | |
873 | return ret; | |
874 | ||
875 | ret = call_write_iter(file, iocb, iter); | |
876 | if (ret > 0) | |
877 | fsnotify_modify(file); | |
878 | ||
879 | return ret; | |
880 | } | |
881 | EXPORT_SYMBOL(vfs_iocb_iter_write); | |
882 | ||
abbb6589 | 883 | ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos, |
ddef7ed2 | 884 | rwf_t flags) |
abbb6589 CH |
885 | { |
886 | if (!file->f_op->write_iter) | |
887 | return -EINVAL; | |
888 | return do_iter_write(file, iter, ppos, flags); | |
889 | } | |
890 | EXPORT_SYMBOL(vfs_iter_write); | |
891 | ||
1da177e4 | 892 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, |
ddef7ed2 | 893 | unsigned long vlen, loff_t *pos, rwf_t flags) |
1da177e4 | 894 | { |
7687a7a4 MS |
895 | struct iovec iovstack[UIO_FASTIOV]; |
896 | struct iovec *iov = iovstack; | |
897 | struct iov_iter iter; | |
898 | ssize_t ret; | |
1da177e4 | 899 | |
251b42a1 | 900 | ret = import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter); |
edab5fe3 CH |
901 | if (ret >= 0) { |
902 | ret = do_iter_read(file, &iter, pos, flags); | |
903 | kfree(iov); | |
904 | } | |
1da177e4 | 905 | |
251b42a1 CH |
906 | return ret; |
907 | } | |
1da177e4 | 908 | |
9725d4ce | 909 | static ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, |
ddef7ed2 | 910 | unsigned long vlen, loff_t *pos, rwf_t flags) |
1da177e4 | 911 | { |
251b42a1 CH |
912 | struct iovec iovstack[UIO_FASTIOV]; |
913 | struct iovec *iov = iovstack; | |
914 | struct iov_iter iter; | |
915 | ssize_t ret; | |
1da177e4 | 916 | |
251b42a1 | 917 | ret = import_iovec(WRITE, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter); |
edab5fe3 | 918 | if (ret >= 0) { |
62473a2d | 919 | file_start_write(file); |
edab5fe3 | 920 | ret = do_iter_write(file, &iter, pos, flags); |
62473a2d | 921 | file_end_write(file); |
edab5fe3 CH |
922 | kfree(iov); |
923 | } | |
251b42a1 | 924 | return ret; |
1da177e4 | 925 | } |
1da177e4 | 926 | |
f17d8b35 | 927 | static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec, |
ddef7ed2 | 928 | unsigned long vlen, rwf_t flags) |
1da177e4 | 929 | { |
9c225f26 | 930 | struct fd f = fdget_pos(fd); |
1da177e4 | 931 | ssize_t ret = -EBADF; |
1da177e4 | 932 | |
2903ff01 | 933 | if (f.file) { |
438ab720 KS |
934 | loff_t pos, *ppos = file_ppos(f.file); |
935 | if (ppos) { | |
936 | pos = *ppos; | |
937 | ppos = &pos; | |
938 | } | |
939 | ret = vfs_readv(f.file, vec, vlen, ppos, flags); | |
940 | if (ret >= 0 && ppos) | |
941 | f.file->f_pos = pos; | |
9c225f26 | 942 | fdput_pos(f); |
1da177e4 LT |
943 | } |
944 | ||
945 | if (ret > 0) | |
4b98d11b AD |
946 | add_rchar(current, ret); |
947 | inc_syscr(current); | |
1da177e4 LT |
948 | return ret; |
949 | } | |
950 | ||
f17d8b35 | 951 | static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec, |
ddef7ed2 | 952 | unsigned long vlen, rwf_t flags) |
1da177e4 | 953 | { |
9c225f26 | 954 | struct fd f = fdget_pos(fd); |
1da177e4 | 955 | ssize_t ret = -EBADF; |
1da177e4 | 956 | |
2903ff01 | 957 | if (f.file) { |
438ab720 KS |
958 | loff_t pos, *ppos = file_ppos(f.file); |
959 | if (ppos) { | |
960 | pos = *ppos; | |
961 | ppos = &pos; | |
962 | } | |
963 | ret = vfs_writev(f.file, vec, vlen, ppos, flags); | |
964 | if (ret >= 0 && ppos) | |
965 | f.file->f_pos = pos; | |
9c225f26 | 966 | fdput_pos(f); |
1da177e4 LT |
967 | } |
968 | ||
969 | if (ret > 0) | |
4b98d11b AD |
970 | add_wchar(current, ret); |
971 | inc_syscw(current); | |
1da177e4 LT |
972 | return ret; |
973 | } | |
974 | ||
601cc11d LT |
975 | static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) |
976 | { | |
977 | #define HALF_LONG_BITS (BITS_PER_LONG / 2) | |
978 | return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; | |
979 | } | |
980 | ||
f17d8b35 | 981 | static ssize_t do_preadv(unsigned long fd, const struct iovec __user *vec, |
ddef7ed2 | 982 | unsigned long vlen, loff_t pos, rwf_t flags) |
f3554f4b | 983 | { |
2903ff01 | 984 | struct fd f; |
f3554f4b | 985 | ssize_t ret = -EBADF; |
f3554f4b GH |
986 | |
987 | if (pos < 0) | |
988 | return -EINVAL; | |
989 | ||
2903ff01 AV |
990 | f = fdget(fd); |
991 | if (f.file) { | |
f3554f4b | 992 | ret = -ESPIPE; |
2903ff01 | 993 | if (f.file->f_mode & FMODE_PREAD) |
f17d8b35 | 994 | ret = vfs_readv(f.file, vec, vlen, &pos, flags); |
2903ff01 | 995 | fdput(f); |
f3554f4b GH |
996 | } |
997 | ||
998 | if (ret > 0) | |
999 | add_rchar(current, ret); | |
1000 | inc_syscr(current); | |
1001 | return ret; | |
1002 | } | |
1003 | ||
f17d8b35 | 1004 | static ssize_t do_pwritev(unsigned long fd, const struct iovec __user *vec, |
ddef7ed2 | 1005 | unsigned long vlen, loff_t pos, rwf_t flags) |
f3554f4b | 1006 | { |
2903ff01 | 1007 | struct fd f; |
f3554f4b | 1008 | ssize_t ret = -EBADF; |
f3554f4b GH |
1009 | |
1010 | if (pos < 0) | |
1011 | return -EINVAL; | |
1012 | ||
2903ff01 AV |
1013 | f = fdget(fd); |
1014 | if (f.file) { | |
f3554f4b | 1015 | ret = -ESPIPE; |
2903ff01 | 1016 | if (f.file->f_mode & FMODE_PWRITE) |
f17d8b35 | 1017 | ret = vfs_writev(f.file, vec, vlen, &pos, flags); |
2903ff01 | 1018 | fdput(f); |
f3554f4b GH |
1019 | } |
1020 | ||
1021 | if (ret > 0) | |
1022 | add_wchar(current, ret); | |
1023 | inc_syscw(current); | |
1024 | return ret; | |
1025 | } | |
1026 | ||
f17d8b35 MT |
1027 | SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, |
1028 | unsigned long, vlen) | |
1029 | { | |
1030 | return do_readv(fd, vec, vlen, 0); | |
1031 | } | |
1032 | ||
1033 | SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, | |
1034 | unsigned long, vlen) | |
1035 | { | |
1036 | return do_writev(fd, vec, vlen, 0); | |
1037 | } | |
1038 | ||
1039 | SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, | |
1040 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) | |
1041 | { | |
1042 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1043 | ||
1044 | return do_preadv(fd, vec, vlen, pos, 0); | |
1045 | } | |
1046 | ||
1047 | SYSCALL_DEFINE6(preadv2, unsigned long, fd, const struct iovec __user *, vec, | |
1048 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h, | |
ddef7ed2 | 1049 | rwf_t, flags) |
f17d8b35 MT |
1050 | { |
1051 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1052 | ||
1053 | if (pos == -1) | |
1054 | return do_readv(fd, vec, vlen, flags); | |
1055 | ||
1056 | return do_preadv(fd, vec, vlen, pos, flags); | |
1057 | } | |
1058 | ||
1059 | SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, | |
1060 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) | |
1061 | { | |
1062 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1063 | ||
1064 | return do_pwritev(fd, vec, vlen, pos, 0); | |
1065 | } | |
1066 | ||
1067 | SYSCALL_DEFINE6(pwritev2, unsigned long, fd, const struct iovec __user *, vec, | |
1068 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h, | |
ddef7ed2 | 1069 | rwf_t, flags) |
f17d8b35 MT |
1070 | { |
1071 | loff_t pos = pos_from_hilo(pos_h, pos_l); | |
1072 | ||
1073 | if (pos == -1) | |
1074 | return do_writev(fd, vec, vlen, flags); | |
1075 | ||
1076 | return do_pwritev(fd, vec, vlen, pos, flags); | |
1077 | } | |
1078 | ||
3523a9d4 CH |
1079 | /* |
1080 | * Various compat syscalls. Note that they all pretend to take a native | |
1081 | * iovec - import_iovec will properly treat those as compat_iovecs based on | |
1082 | * in_compat_syscall(). | |
1083 | */ | |
72ec3516 | 1084 | #ifdef CONFIG_COMPAT |
378a10f3 HC |
1085 | #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64 |
1086 | COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, | |
3523a9d4 | 1087 | const struct iovec __user *, vec, |
378a10f3 HC |
1088 | unsigned long, vlen, loff_t, pos) |
1089 | { | |
3523a9d4 | 1090 | return do_preadv(fd, vec, vlen, pos, 0); |
378a10f3 HC |
1091 | } |
1092 | #endif | |
1093 | ||
dfd948e3 | 1094 | COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, |
3523a9d4 | 1095 | const struct iovec __user *, vec, |
dfd948e3 | 1096 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1097 | { |
1098 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 | 1099 | |
3523a9d4 | 1100 | return do_preadv(fd, vec, vlen, pos, 0); |
f17d8b35 MT |
1101 | } |
1102 | ||
3ebfd81f L |
1103 | #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64V2 |
1104 | COMPAT_SYSCALL_DEFINE5(preadv64v2, unsigned long, fd, | |
3523a9d4 | 1105 | const struct iovec __user *, vec, |
ddef7ed2 | 1106 | unsigned long, vlen, loff_t, pos, rwf_t, flags) |
3ebfd81f | 1107 | { |
cc4b1242 | 1108 | if (pos == -1) |
3523a9d4 CH |
1109 | return do_readv(fd, vec, vlen, flags); |
1110 | return do_preadv(fd, vec, vlen, pos, flags); | |
3ebfd81f L |
1111 | } |
1112 | #endif | |
1113 | ||
f17d8b35 | 1114 | COMPAT_SYSCALL_DEFINE6(preadv2, compat_ulong_t, fd, |
3523a9d4 | 1115 | const struct iovec __user *, vec, |
f17d8b35 | 1116 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high, |
ddef7ed2 | 1117 | rwf_t, flags) |
f17d8b35 MT |
1118 | { |
1119 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
1120 | ||
1121 | if (pos == -1) | |
3523a9d4 CH |
1122 | return do_readv(fd, vec, vlen, flags); |
1123 | return do_preadv(fd, vec, vlen, pos, flags); | |
72ec3516 AV |
1124 | } |
1125 | ||
378a10f3 HC |
1126 | #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64 |
1127 | COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, | |
3523a9d4 | 1128 | const struct iovec __user *, vec, |
378a10f3 HC |
1129 | unsigned long, vlen, loff_t, pos) |
1130 | { | |
3523a9d4 | 1131 | return do_pwritev(fd, vec, vlen, pos, 0); |
378a10f3 HC |
1132 | } |
1133 | #endif | |
1134 | ||
dfd948e3 | 1135 | COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, |
3523a9d4 | 1136 | const struct iovec __user *,vec, |
dfd948e3 | 1137 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1138 | { |
1139 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 | 1140 | |
3523a9d4 | 1141 | return do_pwritev(fd, vec, vlen, pos, 0); |
72ec3516 | 1142 | } |
f17d8b35 | 1143 | |
3ebfd81f L |
1144 | #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64V2 |
1145 | COMPAT_SYSCALL_DEFINE5(pwritev64v2, unsigned long, fd, | |
3523a9d4 | 1146 | const struct iovec __user *, vec, |
ddef7ed2 | 1147 | unsigned long, vlen, loff_t, pos, rwf_t, flags) |
3ebfd81f | 1148 | { |
cc4b1242 | 1149 | if (pos == -1) |
3523a9d4 CH |
1150 | return do_writev(fd, vec, vlen, flags); |
1151 | return do_pwritev(fd, vec, vlen, pos, flags); | |
3ebfd81f L |
1152 | } |
1153 | #endif | |
1154 | ||
f17d8b35 | 1155 | COMPAT_SYSCALL_DEFINE6(pwritev2, compat_ulong_t, fd, |
3523a9d4 | 1156 | const struct iovec __user *,vec, |
ddef7ed2 | 1157 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high, rwf_t, flags) |
f17d8b35 MT |
1158 | { |
1159 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
1160 | ||
1161 | if (pos == -1) | |
3523a9d4 CH |
1162 | return do_writev(fd, vec, vlen, flags); |
1163 | return do_pwritev(fd, vec, vlen, pos, flags); | |
72ec3516 | 1164 | } |
3523a9d4 | 1165 | #endif /* CONFIG_COMPAT */ |
72ec3516 | 1166 | |
19f4fc3a AV |
1167 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, |
1168 | size_t count, loff_t max) | |
1da177e4 | 1169 | { |
2903ff01 AV |
1170 | struct fd in, out; |
1171 | struct inode *in_inode, *out_inode; | |
1da177e4 | 1172 | loff_t pos; |
7995bd28 | 1173 | loff_t out_pos; |
1da177e4 | 1174 | ssize_t retval; |
2903ff01 | 1175 | int fl; |
1da177e4 LT |
1176 | |
1177 | /* | |
1178 | * Get input file, and verify that it is ok.. | |
1179 | */ | |
1180 | retval = -EBADF; | |
2903ff01 AV |
1181 | in = fdget(in_fd); |
1182 | if (!in.file) | |
1da177e4 | 1183 | goto out; |
2903ff01 | 1184 | if (!(in.file->f_mode & FMODE_READ)) |
1da177e4 | 1185 | goto fput_in; |
1da177e4 | 1186 | retval = -ESPIPE; |
7995bd28 AV |
1187 | if (!ppos) { |
1188 | pos = in.file->f_pos; | |
1189 | } else { | |
1190 | pos = *ppos; | |
2903ff01 | 1191 | if (!(in.file->f_mode & FMODE_PREAD)) |
1da177e4 | 1192 | goto fput_in; |
7995bd28 AV |
1193 | } |
1194 | retval = rw_verify_area(READ, in.file, &pos, count); | |
e28cc715 | 1195 | if (retval < 0) |
1da177e4 | 1196 | goto fput_in; |
bc61384d AV |
1197 | if (count > MAX_RW_COUNT) |
1198 | count = MAX_RW_COUNT; | |
1da177e4 | 1199 | |
1da177e4 LT |
1200 | /* |
1201 | * Get output file, and verify that it is ok.. | |
1202 | */ | |
1203 | retval = -EBADF; | |
2903ff01 AV |
1204 | out = fdget(out_fd); |
1205 | if (!out.file) | |
1da177e4 | 1206 | goto fput_in; |
2903ff01 | 1207 | if (!(out.file->f_mode & FMODE_WRITE)) |
1da177e4 | 1208 | goto fput_out; |
496ad9aa AV |
1209 | in_inode = file_inode(in.file); |
1210 | out_inode = file_inode(out.file); | |
7995bd28 AV |
1211 | out_pos = out.file->f_pos; |
1212 | retval = rw_verify_area(WRITE, out.file, &out_pos, count); | |
e28cc715 | 1213 | if (retval < 0) |
1da177e4 LT |
1214 | goto fput_out; |
1215 | ||
1da177e4 LT |
1216 | if (!max) |
1217 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); | |
1218 | ||
1da177e4 LT |
1219 | if (unlikely(pos + count > max)) { |
1220 | retval = -EOVERFLOW; | |
1221 | if (pos >= max) | |
1222 | goto fput_out; | |
1223 | count = max - pos; | |
1224 | } | |
1225 | ||
d96e6e71 | 1226 | fl = 0; |
534f2aaa | 1227 | #if 0 |
d96e6e71 JA |
1228 | /* |
1229 | * We need to debate whether we can enable this or not. The | |
1230 | * man page documents EAGAIN return for the output at least, | |
1231 | * and the application is arguably buggy if it doesn't expect | |
1232 | * EAGAIN on a non-blocking file descriptor. | |
1233 | */ | |
2903ff01 | 1234 | if (in.file->f_flags & O_NONBLOCK) |
d96e6e71 | 1235 | fl = SPLICE_F_NONBLOCK; |
534f2aaa | 1236 | #endif |
50cd2c57 | 1237 | file_start_write(out.file); |
7995bd28 | 1238 | retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl); |
50cd2c57 | 1239 | file_end_write(out.file); |
1da177e4 LT |
1240 | |
1241 | if (retval > 0) { | |
4b98d11b AD |
1242 | add_rchar(current, retval); |
1243 | add_wchar(current, retval); | |
a68c2f12 SW |
1244 | fsnotify_access(in.file); |
1245 | fsnotify_modify(out.file); | |
7995bd28 AV |
1246 | out.file->f_pos = out_pos; |
1247 | if (ppos) | |
1248 | *ppos = pos; | |
1249 | else | |
1250 | in.file->f_pos = pos; | |
1da177e4 | 1251 | } |
1da177e4 | 1252 | |
4b98d11b AD |
1253 | inc_syscr(current); |
1254 | inc_syscw(current); | |
7995bd28 | 1255 | if (pos > max) |
1da177e4 LT |
1256 | retval = -EOVERFLOW; |
1257 | ||
1258 | fput_out: | |
2903ff01 | 1259 | fdput(out); |
1da177e4 | 1260 | fput_in: |
2903ff01 | 1261 | fdput(in); |
1da177e4 LT |
1262 | out: |
1263 | return retval; | |
1264 | } | |
1265 | ||
002c8976 | 1266 | SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count) |
1da177e4 LT |
1267 | { |
1268 | loff_t pos; | |
1269 | off_t off; | |
1270 | ssize_t ret; | |
1271 | ||
1272 | if (offset) { | |
1273 | if (unlikely(get_user(off, offset))) | |
1274 | return -EFAULT; | |
1275 | pos = off; | |
1276 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1277 | if (unlikely(put_user(pos, offset))) | |
1278 | return -EFAULT; | |
1279 | return ret; | |
1280 | } | |
1281 | ||
1282 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1283 | } | |
1284 | ||
002c8976 | 1285 | SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count) |
1da177e4 LT |
1286 | { |
1287 | loff_t pos; | |
1288 | ssize_t ret; | |
1289 | ||
1290 | if (offset) { | |
1291 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1292 | return -EFAULT; | |
1293 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1294 | if (unlikely(put_user(pos, offset))) | |
1295 | return -EFAULT; | |
1296 | return ret; | |
1297 | } | |
1298 | ||
1299 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1300 | } | |
19f4fc3a AV |
1301 | |
1302 | #ifdef CONFIG_COMPAT | |
1303 | COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, | |
1304 | compat_off_t __user *, offset, compat_size_t, count) | |
1305 | { | |
1306 | loff_t pos; | |
1307 | off_t off; | |
1308 | ssize_t ret; | |
1309 | ||
1310 | if (offset) { | |
1311 | if (unlikely(get_user(off, offset))) | |
1312 | return -EFAULT; | |
1313 | pos = off; | |
1314 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1315 | if (unlikely(put_user(pos, offset))) | |
1316 | return -EFAULT; | |
1317 | return ret; | |
1318 | } | |
1319 | ||
1320 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1321 | } | |
1322 | ||
1323 | COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, | |
1324 | compat_loff_t __user *, offset, compat_size_t, count) | |
1325 | { | |
1326 | loff_t pos; | |
1327 | ssize_t ret; | |
1328 | ||
1329 | if (offset) { | |
1330 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1331 | return -EFAULT; | |
1332 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1333 | if (unlikely(put_user(pos, offset))) | |
1334 | return -EFAULT; | |
1335 | return ret; | |
1336 | } | |
1337 | ||
1338 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1339 | } | |
1340 | #endif | |
29732938 | 1341 | |
f16acc9d DC |
1342 | /** |
1343 | * generic_copy_file_range - copy data between two files | |
1344 | * @file_in: file structure to read from | |
1345 | * @pos_in: file offset to read from | |
1346 | * @file_out: file structure to write data to | |
1347 | * @pos_out: file offset to write data to | |
1348 | * @len: amount of data to copy | |
1349 | * @flags: copy flags | |
1350 | * | |
1351 | * This is a generic filesystem helper to copy data from one file to another. | |
1352 | * It has no constraints on the source or destination file owners - the files | |
1353 | * can belong to different superblocks and different filesystem types. Short | |
1354 | * copies are allowed. | |
1355 | * | |
1356 | * This should be called from the @file_out filesystem, as per the | |
1357 | * ->copy_file_range() method. | |
1358 | * | |
1359 | * Returns the number of bytes copied or a negative error indicating the | |
1360 | * failure. | |
1361 | */ | |
1362 | ||
1363 | ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, | |
1364 | struct file *file_out, loff_t pos_out, | |
1365 | size_t len, unsigned int flags) | |
1366 | { | |
1367 | return do_splice_direct(file_in, &pos_in, file_out, &pos_out, | |
1368 | len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); | |
1369 | } | |
1370 | EXPORT_SYMBOL(generic_copy_file_range); | |
1371 | ||
64bf5ff5 DC |
1372 | static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in, |
1373 | struct file *file_out, loff_t pos_out, | |
1374 | size_t len, unsigned int flags) | |
1375 | { | |
5dae222a AG |
1376 | /* |
1377 | * Although we now allow filesystems to handle cross sb copy, passing | |
1378 | * a file of the wrong filesystem type to filesystem driver can result | |
1379 | * in an attempt to dereference the wrong type of ->private_data, so | |
1380 | * avoid doing that until we really have a good reason. NFS defines | |
1381 | * several different file_system_type structures, but they all end up | |
1382 | * using the same ->copy_file_range() function pointer. | |
1383 | */ | |
1384 | if (file_out->f_op->copy_file_range && | |
1385 | file_out->f_op->copy_file_range == file_in->f_op->copy_file_range) | |
64bf5ff5 DC |
1386 | return file_out->f_op->copy_file_range(file_in, pos_in, |
1387 | file_out, pos_out, | |
1388 | len, flags); | |
1389 | ||
1390 | return generic_copy_file_range(file_in, pos_in, file_out, pos_out, len, | |
1391 | flags); | |
1392 | } | |
1393 | ||
29732938 ZB |
1394 | /* |
1395 | * copy_file_range() differs from regular file read and write in that it | |
1396 | * specifically allows return partial success. When it does so is up to | |
1397 | * the copy_file_range method. | |
1398 | */ | |
1399 | ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, | |
1400 | struct file *file_out, loff_t pos_out, | |
1401 | size_t len, unsigned int flags) | |
1402 | { | |
29732938 ZB |
1403 | ssize_t ret; |
1404 | ||
1405 | if (flags != 0) | |
1406 | return -EINVAL; | |
1407 | ||
96e6e8f4 AG |
1408 | ret = generic_copy_file_checks(file_in, pos_in, file_out, pos_out, &len, |
1409 | flags); | |
a3171351 AG |
1410 | if (unlikely(ret)) |
1411 | return ret; | |
11cbfb10 | 1412 | |
29732938 | 1413 | ret = rw_verify_area(READ, file_in, &pos_in, len); |
bc61384d AV |
1414 | if (unlikely(ret)) |
1415 | return ret; | |
1416 | ||
1417 | ret = rw_verify_area(WRITE, file_out, &pos_out, len); | |
1418 | if (unlikely(ret)) | |
29732938 ZB |
1419 | return ret; |
1420 | ||
29732938 ZB |
1421 | if (len == 0) |
1422 | return 0; | |
1423 | ||
bfe219d3 | 1424 | file_start_write(file_out); |
29732938 | 1425 | |
a76b5b04 CH |
1426 | /* |
1427 | * Try cloning first, this is supported by more file systems, and | |
1428 | * more efficient if both clone and copy are supported (e.g. NFS). | |
1429 | */ | |
5dae222a AG |
1430 | if (file_in->f_op->remap_file_range && |
1431 | file_inode(file_in)->i_sb == file_inode(file_out)->i_sb) { | |
42ec3d4c DW |
1432 | loff_t cloned; |
1433 | ||
1434 | cloned = file_in->f_op->remap_file_range(file_in, pos_in, | |
1435 | file_out, pos_out, | |
eca3654e DW |
1436 | min_t(loff_t, MAX_RW_COUNT, len), |
1437 | REMAP_FILE_CAN_SHORTEN); | |
42ec3d4c DW |
1438 | if (cloned > 0) { |
1439 | ret = cloned; | |
a76b5b04 CH |
1440 | goto done; |
1441 | } | |
1442 | } | |
1443 | ||
64bf5ff5 DC |
1444 | ret = do_copy_file_range(file_in, pos_in, file_out, pos_out, len, |
1445 | flags); | |
1446 | WARN_ON_ONCE(ret == -EOPNOTSUPP); | |
a76b5b04 | 1447 | done: |
29732938 ZB |
1448 | if (ret > 0) { |
1449 | fsnotify_access(file_in); | |
1450 | add_rchar(current, ret); | |
1451 | fsnotify_modify(file_out); | |
1452 | add_wchar(current, ret); | |
1453 | } | |
a76b5b04 | 1454 | |
29732938 ZB |
1455 | inc_syscr(current); |
1456 | inc_syscw(current); | |
1457 | ||
bfe219d3 | 1458 | file_end_write(file_out); |
29732938 ZB |
1459 | |
1460 | return ret; | |
1461 | } | |
1462 | EXPORT_SYMBOL(vfs_copy_file_range); | |
1463 | ||
1464 | SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in, | |
1465 | int, fd_out, loff_t __user *, off_out, | |
1466 | size_t, len, unsigned int, flags) | |
1467 | { | |
1468 | loff_t pos_in; | |
1469 | loff_t pos_out; | |
1470 | struct fd f_in; | |
1471 | struct fd f_out; | |
1472 | ssize_t ret = -EBADF; | |
1473 | ||
1474 | f_in = fdget(fd_in); | |
1475 | if (!f_in.file) | |
1476 | goto out2; | |
1477 | ||
1478 | f_out = fdget(fd_out); | |
1479 | if (!f_out.file) | |
1480 | goto out1; | |
1481 | ||
1482 | ret = -EFAULT; | |
1483 | if (off_in) { | |
1484 | if (copy_from_user(&pos_in, off_in, sizeof(loff_t))) | |
1485 | goto out; | |
1486 | } else { | |
1487 | pos_in = f_in.file->f_pos; | |
1488 | } | |
1489 | ||
1490 | if (off_out) { | |
1491 | if (copy_from_user(&pos_out, off_out, sizeof(loff_t))) | |
1492 | goto out; | |
1493 | } else { | |
1494 | pos_out = f_out.file->f_pos; | |
1495 | } | |
1496 | ||
1497 | ret = vfs_copy_file_range(f_in.file, pos_in, f_out.file, pos_out, len, | |
1498 | flags); | |
1499 | if (ret > 0) { | |
1500 | pos_in += ret; | |
1501 | pos_out += ret; | |
1502 | ||
1503 | if (off_in) { | |
1504 | if (copy_to_user(off_in, &pos_in, sizeof(loff_t))) | |
1505 | ret = -EFAULT; | |
1506 | } else { | |
1507 | f_in.file->f_pos = pos_in; | |
1508 | } | |
1509 | ||
1510 | if (off_out) { | |
1511 | if (copy_to_user(off_out, &pos_out, sizeof(loff_t))) | |
1512 | ret = -EFAULT; | |
1513 | } else { | |
1514 | f_out.file->f_pos = pos_out; | |
1515 | } | |
1516 | } | |
1517 | ||
1518 | out: | |
1519 | fdput(f_out); | |
1520 | out1: | |
1521 | fdput(f_in); | |
1522 | out2: | |
1523 | return ret; | |
1524 | } | |
04b38d60 | 1525 | |
42ec3d4c DW |
1526 | static int remap_verify_area(struct file *file, loff_t pos, loff_t len, |
1527 | bool write) | |
04b38d60 CH |
1528 | { |
1529 | struct inode *inode = file_inode(file); | |
1530 | ||
42ec3d4c | 1531 | if (unlikely(pos < 0 || len < 0)) |
04b38d60 CH |
1532 | return -EINVAL; |
1533 | ||
1534 | if (unlikely((loff_t) (pos + len) < 0)) | |
1535 | return -EINVAL; | |
1536 | ||
1537 | if (unlikely(inode->i_flctx && mandatory_lock(inode))) { | |
1538 | loff_t end = len ? pos + len - 1 : OFFSET_MAX; | |
1539 | int retval; | |
1540 | ||
1541 | retval = locks_mandatory_area(inode, file, pos, end, | |
1542 | write ? F_WRLCK : F_RDLCK); | |
1543 | if (retval < 0) | |
1544 | return retval; | |
1545 | } | |
1546 | ||
1547 | return security_file_permission(file, write ? MAY_WRITE : MAY_READ); | |
1548 | } | |
07d19dc9 DW |
1549 | /* |
1550 | * Ensure that we don't remap a partial EOF block in the middle of something | |
1551 | * else. Assume that the offsets have already been checked for block | |
1552 | * alignment. | |
1553 | * | |
a5e6ea18 FM |
1554 | * For clone we only link a partial EOF block above or at the destination file's |
1555 | * EOF. For deduplication we accept a partial EOF block only if it ends at the | |
1556 | * destination file's EOF (can not link it into the middle of a file). | |
eca3654e DW |
1557 | * |
1558 | * Shorten the request if possible. | |
07d19dc9 DW |
1559 | */ |
1560 | static int generic_remap_check_len(struct inode *inode_in, | |
1561 | struct inode *inode_out, | |
1562 | loff_t pos_out, | |
42ec3d4c | 1563 | loff_t *len, |
a91ae49b | 1564 | unsigned int remap_flags) |
07d19dc9 DW |
1565 | { |
1566 | u64 blkmask = i_blocksize(inode_in) - 1; | |
eca3654e | 1567 | loff_t new_len = *len; |
07d19dc9 DW |
1568 | |
1569 | if ((*len & blkmask) == 0) | |
1570 | return 0; | |
1571 | ||
a5e6ea18 | 1572 | if (pos_out + *len < i_size_read(inode_out)) |
eca3654e | 1573 | new_len &= ~blkmask; |
07d19dc9 | 1574 | |
eca3654e DW |
1575 | if (new_len == *len) |
1576 | return 0; | |
1577 | ||
1578 | if (remap_flags & REMAP_FILE_CAN_SHORTEN) { | |
1579 | *len = new_len; | |
1580 | return 0; | |
1581 | } | |
1582 | ||
1583 | return (remap_flags & REMAP_FILE_DEDUP) ? -EBADE : -EINVAL; | |
07d19dc9 | 1584 | } |
04b38d60 | 1585 | |
edc58dd0 | 1586 | /* Read a page's worth of file data into the page cache. */ |
c32e5f39 DW |
1587 | static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset) |
1588 | { | |
1589 | struct page *page; | |
1590 | ||
1591 | page = read_mapping_page(inode->i_mapping, offset >> PAGE_SHIFT, NULL); | |
1592 | if (IS_ERR(page)) | |
1593 | return page; | |
1594 | if (!PageUptodate(page)) { | |
1595 | put_page(page); | |
1596 | return ERR_PTR(-EIO); | |
1597 | } | |
c32e5f39 DW |
1598 | return page; |
1599 | } | |
1600 | ||
edc58dd0 DW |
1601 | /* |
1602 | * Lock two pages, ensuring that we lock in offset order if the pages are from | |
1603 | * the same file. | |
1604 | */ | |
1605 | static void vfs_lock_two_pages(struct page *page1, struct page *page2) | |
1606 | { | |
1607 | /* Always lock in order of increasing index. */ | |
1608 | if (page1->index > page2->index) | |
1609 | swap(page1, page2); | |
1610 | ||
1611 | lock_page(page1); | |
1612 | if (page1 != page2) | |
1613 | lock_page(page2); | |
1614 | } | |
1615 | ||
1616 | /* Unlock two pages, being careful not to unlock the same page twice. */ | |
1617 | static void vfs_unlock_two_pages(struct page *page1, struct page *page2) | |
1618 | { | |
1619 | unlock_page(page1); | |
1620 | if (page1 != page2) | |
1621 | unlock_page(page2); | |
1622 | } | |
1623 | ||
c32e5f39 DW |
1624 | /* |
1625 | * Compare extents of two files to see if they are the same. | |
1626 | * Caller must have locked both inodes to prevent write races. | |
1627 | */ | |
1628 | static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, | |
1629 | struct inode *dest, loff_t destoff, | |
1630 | loff_t len, bool *is_same) | |
1631 | { | |
1632 | loff_t src_poff; | |
1633 | loff_t dest_poff; | |
1634 | void *src_addr; | |
1635 | void *dest_addr; | |
1636 | struct page *src_page; | |
1637 | struct page *dest_page; | |
1638 | loff_t cmp_len; | |
1639 | bool same; | |
1640 | int error; | |
1641 | ||
1642 | error = -EINVAL; | |
1643 | same = true; | |
1644 | while (len) { | |
1645 | src_poff = srcoff & (PAGE_SIZE - 1); | |
1646 | dest_poff = destoff & (PAGE_SIZE - 1); | |
1647 | cmp_len = min(PAGE_SIZE - src_poff, | |
1648 | PAGE_SIZE - dest_poff); | |
1649 | cmp_len = min(cmp_len, len); | |
1650 | if (cmp_len <= 0) | |
1651 | goto out_error; | |
1652 | ||
1653 | src_page = vfs_dedupe_get_page(src, srcoff); | |
1654 | if (IS_ERR(src_page)) { | |
1655 | error = PTR_ERR(src_page); | |
1656 | goto out_error; | |
1657 | } | |
1658 | dest_page = vfs_dedupe_get_page(dest, destoff); | |
1659 | if (IS_ERR(dest_page)) { | |
1660 | error = PTR_ERR(dest_page); | |
c32e5f39 DW |
1661 | put_page(src_page); |
1662 | goto out_error; | |
1663 | } | |
edc58dd0 DW |
1664 | |
1665 | vfs_lock_two_pages(src_page, dest_page); | |
1666 | ||
1667 | /* | |
1668 | * Now that we've locked both pages, make sure they're still | |
1669 | * mapped to the file data we're interested in. If not, | |
1670 | * someone is invalidating pages on us and we lose. | |
1671 | */ | |
1672 | if (!PageUptodate(src_page) || !PageUptodate(dest_page) || | |
1673 | src_page->mapping != src->i_mapping || | |
1674 | dest_page->mapping != dest->i_mapping) { | |
1675 | same = false; | |
1676 | goto unlock; | |
1677 | } | |
1678 | ||
c32e5f39 DW |
1679 | src_addr = kmap_atomic(src_page); |
1680 | dest_addr = kmap_atomic(dest_page); | |
1681 | ||
1682 | flush_dcache_page(src_page); | |
1683 | flush_dcache_page(dest_page); | |
1684 | ||
1685 | if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) | |
1686 | same = false; | |
1687 | ||
1688 | kunmap_atomic(dest_addr); | |
1689 | kunmap_atomic(src_addr); | |
edc58dd0 DW |
1690 | unlock: |
1691 | vfs_unlock_two_pages(src_page, dest_page); | |
c32e5f39 DW |
1692 | put_page(dest_page); |
1693 | put_page(src_page); | |
1694 | ||
1695 | if (!same) | |
1696 | break; | |
1697 | ||
1698 | srcoff += cmp_len; | |
1699 | destoff += cmp_len; | |
1700 | len -= cmp_len; | |
1701 | } | |
1702 | ||
1703 | *is_same = same; | |
1704 | return 0; | |
1705 | ||
1706 | out_error: | |
1707 | return error; | |
1708 | } | |
04b38d60 | 1709 | |
876bec6f DW |
1710 | /* |
1711 | * Check that the two inodes are eligible for cloning, the ranges make | |
1712 | * sense, and then flush all dirty data. Caller must ensure that the | |
1713 | * inodes have been locked against any other modifications. | |
22725ce4 | 1714 | * |
8c5c836b DW |
1715 | * If there's an error, then the usual negative error code is returned. |
1716 | * Otherwise returns 0 with *len set to the request length. | |
876bec6f | 1717 | */ |
a83ab01a DW |
1718 | int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, |
1719 | struct file *file_out, loff_t pos_out, | |
42ec3d4c | 1720 | loff_t *len, unsigned int remap_flags) |
876bec6f | 1721 | { |
1383a7ed DW |
1722 | struct inode *inode_in = file_inode(file_in); |
1723 | struct inode *inode_out = file_inode(file_out); | |
876bec6f DW |
1724 | bool same_inode = (inode_in == inode_out); |
1725 | int ret; | |
1726 | ||
1727 | /* Don't touch certain kinds of inodes */ | |
1728 | if (IS_IMMUTABLE(inode_out)) | |
1729 | return -EPERM; | |
1730 | ||
1731 | if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out)) | |
1732 | return -ETXTBSY; | |
1733 | ||
1734 | /* Don't reflink dirs, pipes, sockets... */ | |
1735 | if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) | |
1736 | return -EISDIR; | |
1737 | if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) | |
1738 | return -EINVAL; | |
1739 | ||
876bec6f DW |
1740 | /* Zero length dedupe exits immediately; reflink goes to EOF. */ |
1741 | if (*len == 0) { | |
1383a7ed DW |
1742 | loff_t isize = i_size_read(inode_in); |
1743 | ||
a91ae49b | 1744 | if ((remap_flags & REMAP_FILE_DEDUP) || pos_in == isize) |
876bec6f | 1745 | return 0; |
22725ce4 DW |
1746 | if (pos_in > isize) |
1747 | return -EINVAL; | |
876bec6f | 1748 | *len = isize - pos_in; |
2c5773f1 DW |
1749 | if (*len == 0) |
1750 | return 0; | |
876bec6f DW |
1751 | } |
1752 | ||
1383a7ed DW |
1753 | /* Check that we don't violate system file offset limits. */ |
1754 | ret = generic_remap_checks(file_in, pos_in, file_out, pos_out, len, | |
3d28193e | 1755 | remap_flags); |
1383a7ed DW |
1756 | if (ret) |
1757 | return ret; | |
876bec6f DW |
1758 | |
1759 | /* Wait for the completion of any pending IOs on both files */ | |
1760 | inode_dio_wait(inode_in); | |
1761 | if (!same_inode) | |
1762 | inode_dio_wait(inode_out); | |
1763 | ||
1764 | ret = filemap_write_and_wait_range(inode_in->i_mapping, | |
1765 | pos_in, pos_in + *len - 1); | |
1766 | if (ret) | |
1767 | return ret; | |
1768 | ||
1769 | ret = filemap_write_and_wait_range(inode_out->i_mapping, | |
1770 | pos_out, pos_out + *len - 1); | |
1771 | if (ret) | |
1772 | return ret; | |
1773 | ||
1774 | /* | |
1775 | * Check that the extents are the same. | |
1776 | */ | |
a91ae49b | 1777 | if (remap_flags & REMAP_FILE_DEDUP) { |
876bec6f DW |
1778 | bool is_same = false; |
1779 | ||
1780 | ret = vfs_dedupe_file_range_compare(inode_in, pos_in, | |
1781 | inode_out, pos_out, *len, &is_same); | |
1782 | if (ret) | |
1783 | return ret; | |
1784 | if (!is_same) | |
1785 | return -EBADE; | |
1786 | } | |
1787 | ||
07d19dc9 | 1788 | ret = generic_remap_check_len(inode_in, inode_out, pos_out, len, |
a91ae49b | 1789 | remap_flags); |
07d19dc9 DW |
1790 | if (ret) |
1791 | return ret; | |
1792 | ||
8dde90bc | 1793 | /* If can't alter the file contents, we're done. */ |
e38f7f53 AG |
1794 | if (!(remap_flags & REMAP_FILE_DEDUP)) |
1795 | ret = file_modified(file_out); | |
8dde90bc | 1796 | |
e38f7f53 | 1797 | return ret; |
876bec6f | 1798 | } |
a83ab01a | 1799 | EXPORT_SYMBOL(generic_remap_file_range_prep); |
876bec6f | 1800 | |
42ec3d4c | 1801 | loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, |
452ce659 DW |
1802 | struct file *file_out, loff_t pos_out, |
1803 | loff_t len, unsigned int remap_flags) | |
04b38d60 | 1804 | { |
42ec3d4c | 1805 | loff_t ret; |
04b38d60 | 1806 | |
6744557b | 1807 | WARN_ON_ONCE(remap_flags & REMAP_FILE_DEDUP); |
04b38d60 | 1808 | |
913b86e9 AG |
1809 | /* |
1810 | * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on | |
1811 | * the same mount. Practically, they only need to be on the same file | |
1812 | * system. | |
1813 | */ | |
a3171351 | 1814 | if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) |
04b38d60 CH |
1815 | return -EXDEV; |
1816 | ||
a3171351 AG |
1817 | ret = generic_file_rw_checks(file_in, file_out); |
1818 | if (ret < 0) | |
1819 | return ret; | |
04b38d60 | 1820 | |
2e5dfc99 | 1821 | if (!file_in->f_op->remap_file_range) |
0fcbf996 CH |
1822 | return -EOPNOTSUPP; |
1823 | ||
6095028b | 1824 | ret = remap_verify_area(file_in, pos_in, len, false); |
04b38d60 CH |
1825 | if (ret) |
1826 | return ret; | |
1827 | ||
6095028b | 1828 | ret = remap_verify_area(file_out, pos_out, len, true); |
04b38d60 CH |
1829 | if (ret) |
1830 | return ret; | |
1831 | ||
2e5dfc99 | 1832 | ret = file_in->f_op->remap_file_range(file_in, pos_in, |
452ce659 | 1833 | file_out, pos_out, len, remap_flags); |
42ec3d4c DW |
1834 | if (ret < 0) |
1835 | return ret; | |
04b38d60 | 1836 | |
42ec3d4c DW |
1837 | fsnotify_access(file_in); |
1838 | fsnotify_modify(file_out); | |
04b38d60 CH |
1839 | return ret; |
1840 | } | |
a725356b AG |
1841 | EXPORT_SYMBOL(do_clone_file_range); |
1842 | ||
42ec3d4c | 1843 | loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in, |
452ce659 DW |
1844 | struct file *file_out, loff_t pos_out, |
1845 | loff_t len, unsigned int remap_flags) | |
a725356b | 1846 | { |
42ec3d4c | 1847 | loff_t ret; |
a725356b AG |
1848 | |
1849 | file_start_write(file_out); | |
452ce659 DW |
1850 | ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len, |
1851 | remap_flags); | |
a725356b AG |
1852 | file_end_write(file_out); |
1853 | ||
1854 | return ret; | |
1855 | } | |
04b38d60 | 1856 | EXPORT_SYMBOL(vfs_clone_file_range); |
54dbc151 | 1857 | |
5de4480a MF |
1858 | /* Check whether we are allowed to dedupe the destination file */ |
1859 | static bool allow_file_dedupe(struct file *file) | |
1860 | { | |
1861 | if (capable(CAP_SYS_ADMIN)) | |
1862 | return true; | |
1863 | if (file->f_mode & FMODE_WRITE) | |
1864 | return true; | |
1865 | if (uid_eq(current_fsuid(), file_inode(file)->i_uid)) | |
1866 | return true; | |
1867 | if (!inode_permission(file_inode(file), MAY_WRITE)) | |
1868 | return true; | |
1869 | return false; | |
1870 | } | |
1871 | ||
42ec3d4c DW |
1872 | loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, |
1873 | struct file *dst_file, loff_t dst_pos, | |
df365836 | 1874 | loff_t len, unsigned int remap_flags) |
1b4f42a1 | 1875 | { |
42ec3d4c | 1876 | loff_t ret; |
1b4f42a1 | 1877 | |
eca3654e DW |
1878 | WARN_ON_ONCE(remap_flags & ~(REMAP_FILE_DEDUP | |
1879 | REMAP_FILE_CAN_SHORTEN)); | |
1b4f42a1 MS |
1880 | |
1881 | ret = mnt_want_write_file(dst_file); | |
1882 | if (ret) | |
1883 | return ret; | |
1884 | ||
6095028b | 1885 | ret = remap_verify_area(dst_file, dst_pos, len, true); |
1b4f42a1 MS |
1886 | if (ret < 0) |
1887 | goto out_drop_write; | |
1888 | ||
85c95f20 | 1889 | ret = -EPERM; |
5de4480a | 1890 | if (!allow_file_dedupe(dst_file)) |
1b4f42a1 MS |
1891 | goto out_drop_write; |
1892 | ||
1893 | ret = -EXDEV; | |
1894 | if (src_file->f_path.mnt != dst_file->f_path.mnt) | |
1895 | goto out_drop_write; | |
1896 | ||
1897 | ret = -EISDIR; | |
1898 | if (S_ISDIR(file_inode(dst_file)->i_mode)) | |
1899 | goto out_drop_write; | |
1900 | ||
1901 | ret = -EINVAL; | |
2e5dfc99 | 1902 | if (!dst_file->f_op->remap_file_range) |
1b4f42a1 MS |
1903 | goto out_drop_write; |
1904 | ||
9aae2050 DW |
1905 | if (len == 0) { |
1906 | ret = 0; | |
1907 | goto out_drop_write; | |
1908 | } | |
1909 | ||
2e5dfc99 | 1910 | ret = dst_file->f_op->remap_file_range(src_file, src_pos, dst_file, |
df365836 | 1911 | dst_pos, len, remap_flags | REMAP_FILE_DEDUP); |
1b4f42a1 MS |
1912 | out_drop_write: |
1913 | mnt_drop_write_file(dst_file); | |
1914 | ||
1915 | return ret; | |
1916 | } | |
f1825366 | 1917 | EXPORT_SYMBOL(vfs_dedupe_file_range_one); |
1b4f42a1 | 1918 | |
54dbc151 DW |
1919 | int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same) |
1920 | { | |
1921 | struct file_dedupe_range_info *info; | |
1922 | struct inode *src = file_inode(file); | |
1923 | u64 off; | |
1924 | u64 len; | |
1925 | int i; | |
1926 | int ret; | |
54dbc151 | 1927 | u16 count = same->dest_count; |
42ec3d4c | 1928 | loff_t deduped; |
54dbc151 DW |
1929 | |
1930 | if (!(file->f_mode & FMODE_READ)) | |
1931 | return -EINVAL; | |
1932 | ||
1933 | if (same->reserved1 || same->reserved2) | |
1934 | return -EINVAL; | |
1935 | ||
1936 | off = same->src_offset; | |
1937 | len = same->src_length; | |
1938 | ||
54dbc151 | 1939 | if (S_ISDIR(src->i_mode)) |
494633fa | 1940 | return -EISDIR; |
54dbc151 | 1941 | |
54dbc151 | 1942 | if (!S_ISREG(src->i_mode)) |
494633fa DC |
1943 | return -EINVAL; |
1944 | ||
1945 | if (!file->f_op->remap_file_range) | |
1946 | return -EOPNOTSUPP; | |
54dbc151 | 1947 | |
6095028b | 1948 | ret = remap_verify_area(file, off, len, false); |
54dbc151 | 1949 | if (ret < 0) |
494633fa | 1950 | return ret; |
54dbc151 DW |
1951 | ret = 0; |
1952 | ||
22725ce4 DW |
1953 | if (off + len > i_size_read(src)) |
1954 | return -EINVAL; | |
1955 | ||
92b66d2c MS |
1956 | /* Arbitrary 1G limit on a single dedupe request, can be raised. */ |
1957 | len = min_t(u64, len, 1 << 30); | |
1958 | ||
54dbc151 DW |
1959 | /* pre-format output fields to sane values */ |
1960 | for (i = 0; i < count; i++) { | |
1961 | same->info[i].bytes_deduped = 0ULL; | |
1962 | same->info[i].status = FILE_DEDUPE_RANGE_SAME; | |
1963 | } | |
1964 | ||
1965 | for (i = 0, info = same->info; i < count; i++, info++) { | |
54dbc151 | 1966 | struct fd dst_fd = fdget(info->dest_fd); |
1b4f42a1 | 1967 | struct file *dst_file = dst_fd.file; |
54dbc151 | 1968 | |
54dbc151 DW |
1969 | if (!dst_file) { |
1970 | info->status = -EBADF; | |
1971 | goto next_loop; | |
1972 | } | |
54dbc151 DW |
1973 | |
1974 | if (info->reserved) { | |
1975 | info->status = -EINVAL; | |
1b4f42a1 | 1976 | goto next_fdput; |
54dbc151 DW |
1977 | } |
1978 | ||
1b4f42a1 | 1979 | deduped = vfs_dedupe_file_range_one(file, off, dst_file, |
df365836 | 1980 | info->dest_offset, len, |
eca3654e | 1981 | REMAP_FILE_CAN_SHORTEN); |
1b4f42a1 MS |
1982 | if (deduped == -EBADE) |
1983 | info->status = FILE_DEDUPE_RANGE_DIFFERS; | |
1984 | else if (deduped < 0) | |
1985 | info->status = deduped; | |
1986 | else | |
1987 | info->bytes_deduped = len; | |
1988 | ||
22762711 | 1989 | next_fdput: |
54dbc151 | 1990 | fdput(dst_fd); |
22762711 | 1991 | next_loop: |
e62e560f | 1992 | if (fatal_signal_pending(current)) |
494633fa | 1993 | break; |
54dbc151 | 1994 | } |
54dbc151 DW |
1995 | return ret; |
1996 | } | |
1997 | EXPORT_SYMBOL(vfs_dedupe_file_range); |