Commit | Line | Data |
---|---|---|
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> | |
12 | #include <linux/smp_lock.h> | |
0eeca283 | 13 | #include <linux/fsnotify.h> |
1da177e4 LT |
14 | #include <linux/security.h> |
15 | #include <linux/module.h> | |
16 | #include <linux/syscalls.h> | |
e28cc715 | 17 | #include <linux/pagemap.h> |
ee0b3e67 | 18 | #include "read_write.h" |
1da177e4 LT |
19 | |
20 | #include <asm/uaccess.h> | |
21 | #include <asm/unistd.h> | |
22 | ||
4b6f5d20 | 23 | const struct file_operations generic_ro_fops = { |
1da177e4 LT |
24 | .llseek = generic_file_llseek, |
25 | .read = generic_file_read, | |
26 | .mmap = generic_file_readonly_mmap, | |
27 | .sendfile = generic_file_sendfile, | |
28 | }; | |
29 | ||
30 | EXPORT_SYMBOL(generic_ro_fops); | |
31 | ||
32 | loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) | |
33 | { | |
34 | long long retval; | |
35 | struct inode *inode = file->f_mapping->host; | |
36 | ||
1b1dcc1b | 37 | mutex_lock(&inode->i_mutex); |
1da177e4 LT |
38 | switch (origin) { |
39 | case 2: | |
40 | offset += inode->i_size; | |
41 | break; | |
42 | case 1: | |
43 | offset += file->f_pos; | |
44 | } | |
45 | retval = -EINVAL; | |
46 | if (offset>=0 && offset<=inode->i_sb->s_maxbytes) { | |
47 | if (offset != file->f_pos) { | |
48 | file->f_pos = offset; | |
49 | file->f_version = 0; | |
50 | } | |
51 | retval = offset; | |
52 | } | |
1b1dcc1b | 53 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
54 | return retval; |
55 | } | |
56 | ||
57 | EXPORT_SYMBOL(generic_file_llseek); | |
58 | ||
59 | loff_t remote_llseek(struct file *file, loff_t offset, int origin) | |
60 | { | |
61 | long long retval; | |
62 | ||
63 | lock_kernel(); | |
64 | switch (origin) { | |
65 | case 2: | |
66 | offset += i_size_read(file->f_dentry->d_inode); | |
67 | break; | |
68 | case 1: | |
69 | offset += file->f_pos; | |
70 | } | |
71 | retval = -EINVAL; | |
72 | if (offset>=0 && offset<=file->f_dentry->d_inode->i_sb->s_maxbytes) { | |
73 | if (offset != file->f_pos) { | |
74 | file->f_pos = offset; | |
75 | file->f_version = 0; | |
76 | } | |
77 | retval = offset; | |
78 | } | |
79 | unlock_kernel(); | |
80 | return retval; | |
81 | } | |
82 | EXPORT_SYMBOL(remote_llseek); | |
83 | ||
84 | loff_t no_llseek(struct file *file, loff_t offset, int origin) | |
85 | { | |
86 | return -ESPIPE; | |
87 | } | |
88 | EXPORT_SYMBOL(no_llseek); | |
89 | ||
90 | loff_t default_llseek(struct file *file, loff_t offset, int origin) | |
91 | { | |
92 | long long retval; | |
93 | ||
94 | lock_kernel(); | |
95 | switch (origin) { | |
96 | case 2: | |
97 | offset += i_size_read(file->f_dentry->d_inode); | |
98 | break; | |
99 | case 1: | |
100 | offset += file->f_pos; | |
101 | } | |
102 | retval = -EINVAL; | |
103 | if (offset >= 0) { | |
104 | if (offset != file->f_pos) { | |
105 | file->f_pos = offset; | |
106 | file->f_version = 0; | |
107 | } | |
108 | retval = offset; | |
109 | } | |
110 | unlock_kernel(); | |
111 | return retval; | |
112 | } | |
113 | EXPORT_SYMBOL(default_llseek); | |
114 | ||
115 | loff_t vfs_llseek(struct file *file, loff_t offset, int origin) | |
116 | { | |
117 | loff_t (*fn)(struct file *, loff_t, int); | |
118 | ||
119 | fn = no_llseek; | |
120 | if (file->f_mode & FMODE_LSEEK) { | |
121 | fn = default_llseek; | |
122 | if (file->f_op && file->f_op->llseek) | |
123 | fn = file->f_op->llseek; | |
124 | } | |
125 | return fn(file, offset, origin); | |
126 | } | |
127 | EXPORT_SYMBOL(vfs_llseek); | |
128 | ||
129 | asmlinkage off_t sys_lseek(unsigned int fd, off_t offset, unsigned int origin) | |
130 | { | |
131 | off_t retval; | |
132 | struct file * file; | |
133 | int fput_needed; | |
134 | ||
135 | retval = -EBADF; | |
136 | file = fget_light(fd, &fput_needed); | |
137 | if (!file) | |
138 | goto bad; | |
139 | ||
140 | retval = -EINVAL; | |
141 | if (origin <= 2) { | |
142 | loff_t res = vfs_llseek(file, offset, origin); | |
143 | retval = res; | |
144 | if (res != (loff_t)retval) | |
145 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ | |
146 | } | |
147 | fput_light(file, fput_needed); | |
148 | bad: | |
149 | return retval; | |
150 | } | |
151 | ||
152 | #ifdef __ARCH_WANT_SYS_LLSEEK | |
153 | asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high, | |
154 | unsigned long offset_low, loff_t __user * result, | |
155 | unsigned int origin) | |
156 | { | |
157 | int retval; | |
158 | struct file * file; | |
159 | loff_t offset; | |
160 | int fput_needed; | |
161 | ||
162 | retval = -EBADF; | |
163 | file = fget_light(fd, &fput_needed); | |
164 | if (!file) | |
165 | goto bad; | |
166 | ||
167 | retval = -EINVAL; | |
168 | if (origin > 2) | |
169 | goto out_putf; | |
170 | ||
171 | offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low, | |
172 | origin); | |
173 | ||
174 | retval = (int)offset; | |
175 | if (offset >= 0) { | |
176 | retval = -EFAULT; | |
177 | if (!copy_to_user(result, &offset, sizeof(offset))) | |
178 | retval = 0; | |
179 | } | |
180 | out_putf: | |
181 | fput_light(file, fput_needed); | |
182 | bad: | |
183 | return retval; | |
184 | } | |
185 | #endif | |
186 | ||
e28cc715 LT |
187 | /* |
188 | * rw_verify_area doesn't like huge counts. We limit | |
189 | * them to something that fits in "int" so that others | |
190 | * won't have to do range checks all the time. | |
191 | */ | |
192 | #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK) | |
1da177e4 LT |
193 | |
194 | int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count) | |
195 | { | |
196 | struct inode *inode; | |
197 | loff_t pos; | |
198 | ||
e28cc715 | 199 | if (unlikely((ssize_t) count < 0)) |
1da177e4 LT |
200 | goto Einval; |
201 | pos = *ppos; | |
202 | if (unlikely((pos < 0) || (loff_t) (pos + count) < 0)) | |
203 | goto Einval; | |
204 | ||
205 | inode = file->f_dentry->d_inode; | |
49570e9b | 206 | if (unlikely(inode->i_flock && MANDATORY_LOCK(inode))) { |
e28cc715 LT |
207 | int retval = locks_mandatory_area( |
208 | read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, | |
209 | inode, file, pos, count); | |
210 | if (retval < 0) | |
211 | return retval; | |
212 | } | |
213 | return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; | |
1da177e4 LT |
214 | |
215 | Einval: | |
216 | return -EINVAL; | |
217 | } | |
218 | ||
63e68809 BL |
219 | static void wait_on_retry_sync_kiocb(struct kiocb *iocb) |
220 | { | |
221 | set_current_state(TASK_UNINTERRUPTIBLE); | |
222 | if (!kiocbIsKicked(iocb)) | |
223 | schedule(); | |
224 | else | |
225 | kiocbClearKicked(iocb); | |
226 | __set_current_state(TASK_RUNNING); | |
227 | } | |
228 | ||
1da177e4 LT |
229 | ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
230 | { | |
027445c3 | 231 | struct iovec iov = { .iov_base = buf, .iov_len = len }; |
1da177e4 LT |
232 | struct kiocb kiocb; |
233 | ssize_t ret; | |
234 | ||
235 | init_sync_kiocb(&kiocb, filp); | |
236 | kiocb.ki_pos = *ppos; | |
027445c3 BP |
237 | kiocb.ki_left = len; |
238 | ||
239 | for (;;) { | |
240 | ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); | |
241 | if (ret != -EIOCBRETRY) | |
242 | break; | |
63e68809 | 243 | wait_on_retry_sync_kiocb(&kiocb); |
027445c3 | 244 | } |
63e68809 | 245 | |
1da177e4 LT |
246 | if (-EIOCBQUEUED == ret) |
247 | ret = wait_on_sync_kiocb(&kiocb); | |
248 | *ppos = kiocb.ki_pos; | |
249 | return ret; | |
250 | } | |
251 | ||
252 | EXPORT_SYMBOL(do_sync_read); | |
253 | ||
254 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) | |
255 | { | |
256 | ssize_t ret; | |
257 | ||
258 | if (!(file->f_mode & FMODE_READ)) | |
259 | return -EBADF; | |
260 | if (!file->f_op || (!file->f_op->read && !file->f_op->aio_read)) | |
261 | return -EINVAL; | |
262 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) | |
263 | return -EFAULT; | |
264 | ||
265 | ret = rw_verify_area(READ, file, pos, count); | |
e28cc715 LT |
266 | if (ret >= 0) { |
267 | count = ret; | |
1da177e4 LT |
268 | ret = security_file_permission (file, MAY_READ); |
269 | if (!ret) { | |
270 | if (file->f_op->read) | |
271 | ret = file->f_op->read(file, buf, count, pos); | |
272 | else | |
273 | ret = do_sync_read(file, buf, count, pos); | |
274 | if (ret > 0) { | |
0eeca283 | 275 | fsnotify_access(file->f_dentry); |
1da177e4 LT |
276 | current->rchar += ret; |
277 | } | |
278 | current->syscr++; | |
279 | } | |
280 | } | |
281 | ||
282 | return ret; | |
283 | } | |
284 | ||
285 | EXPORT_SYMBOL(vfs_read); | |
286 | ||
287 | ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) | |
288 | { | |
027445c3 | 289 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; |
1da177e4 LT |
290 | struct kiocb kiocb; |
291 | ssize_t ret; | |
292 | ||
293 | init_sync_kiocb(&kiocb, filp); | |
294 | kiocb.ki_pos = *ppos; | |
027445c3 BP |
295 | kiocb.ki_left = len; |
296 | ||
297 | for (;;) { | |
298 | ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); | |
299 | if (ret != -EIOCBRETRY) | |
300 | break; | |
63e68809 | 301 | wait_on_retry_sync_kiocb(&kiocb); |
027445c3 | 302 | } |
63e68809 | 303 | |
1da177e4 LT |
304 | if (-EIOCBQUEUED == ret) |
305 | ret = wait_on_sync_kiocb(&kiocb); | |
306 | *ppos = kiocb.ki_pos; | |
307 | return ret; | |
308 | } | |
309 | ||
310 | EXPORT_SYMBOL(do_sync_write); | |
311 | ||
312 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) | |
313 | { | |
314 | ssize_t ret; | |
315 | ||
316 | if (!(file->f_mode & FMODE_WRITE)) | |
317 | return -EBADF; | |
318 | if (!file->f_op || (!file->f_op->write && !file->f_op->aio_write)) | |
319 | return -EINVAL; | |
320 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) | |
321 | return -EFAULT; | |
322 | ||
323 | ret = rw_verify_area(WRITE, file, pos, count); | |
e28cc715 LT |
324 | if (ret >= 0) { |
325 | count = ret; | |
1da177e4 LT |
326 | ret = security_file_permission (file, MAY_WRITE); |
327 | if (!ret) { | |
328 | if (file->f_op->write) | |
329 | ret = file->f_op->write(file, buf, count, pos); | |
330 | else | |
331 | ret = do_sync_write(file, buf, count, pos); | |
332 | if (ret > 0) { | |
0eeca283 | 333 | fsnotify_modify(file->f_dentry); |
1da177e4 LT |
334 | current->wchar += ret; |
335 | } | |
336 | current->syscw++; | |
337 | } | |
338 | } | |
339 | ||
340 | return ret; | |
341 | } | |
342 | ||
343 | EXPORT_SYMBOL(vfs_write); | |
344 | ||
345 | static inline loff_t file_pos_read(struct file *file) | |
346 | { | |
347 | return file->f_pos; | |
348 | } | |
349 | ||
350 | static inline void file_pos_write(struct file *file, loff_t pos) | |
351 | { | |
352 | file->f_pos = pos; | |
353 | } | |
354 | ||
355 | asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count) | |
356 | { | |
357 | struct file *file; | |
358 | ssize_t ret = -EBADF; | |
359 | int fput_needed; | |
360 | ||
361 | file = fget_light(fd, &fput_needed); | |
362 | if (file) { | |
363 | loff_t pos = file_pos_read(file); | |
364 | ret = vfs_read(file, buf, count, &pos); | |
365 | file_pos_write(file, pos); | |
366 | fput_light(file, fput_needed); | |
367 | } | |
368 | ||
369 | return ret; | |
370 | } | |
371 | EXPORT_SYMBOL_GPL(sys_read); | |
372 | ||
373 | asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t count) | |
374 | { | |
375 | struct file *file; | |
376 | ssize_t ret = -EBADF; | |
377 | int fput_needed; | |
378 | ||
379 | file = fget_light(fd, &fput_needed); | |
380 | if (file) { | |
381 | loff_t pos = file_pos_read(file); | |
382 | ret = vfs_write(file, buf, count, &pos); | |
383 | file_pos_write(file, pos); | |
384 | fput_light(file, fput_needed); | |
385 | } | |
386 | ||
387 | return ret; | |
388 | } | |
389 | ||
390 | asmlinkage ssize_t sys_pread64(unsigned int fd, char __user *buf, | |
391 | size_t count, loff_t pos) | |
392 | { | |
393 | struct file *file; | |
394 | ssize_t ret = -EBADF; | |
395 | int fput_needed; | |
396 | ||
397 | if (pos < 0) | |
398 | return -EINVAL; | |
399 | ||
400 | file = fget_light(fd, &fput_needed); | |
401 | if (file) { | |
402 | ret = -ESPIPE; | |
403 | if (file->f_mode & FMODE_PREAD) | |
404 | ret = vfs_read(file, buf, count, &pos); | |
405 | fput_light(file, fput_needed); | |
406 | } | |
407 | ||
408 | return ret; | |
409 | } | |
410 | ||
411 | asmlinkage ssize_t sys_pwrite64(unsigned int fd, const char __user *buf, | |
412 | size_t count, loff_t pos) | |
413 | { | |
414 | struct file *file; | |
415 | ssize_t ret = -EBADF; | |
416 | int fput_needed; | |
417 | ||
418 | if (pos < 0) | |
419 | return -EINVAL; | |
420 | ||
421 | file = fget_light(fd, &fput_needed); | |
422 | if (file) { | |
423 | ret = -ESPIPE; | |
424 | if (file->f_mode & FMODE_PWRITE) | |
425 | ret = vfs_write(file, buf, count, &pos); | |
426 | fput_light(file, fput_needed); | |
427 | } | |
428 | ||
429 | return ret; | |
430 | } | |
431 | ||
432 | /* | |
433 | * Reduce an iovec's length in-place. Return the resulting number of segments | |
434 | */ | |
435 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) | |
436 | { | |
437 | unsigned long seg = 0; | |
438 | size_t len = 0; | |
439 | ||
440 | while (seg < nr_segs) { | |
441 | seg++; | |
442 | if (len + iov->iov_len >= to) { | |
443 | iov->iov_len = to - len; | |
444 | break; | |
445 | } | |
446 | len += iov->iov_len; | |
447 | iov++; | |
448 | } | |
449 | return seg; | |
450 | } | |
451 | ||
69c3a5b8 | 452 | EXPORT_UNUSED_SYMBOL(iov_shorten); /* June 2006 */ |
1da177e4 | 453 | |
ee0b3e67 BP |
454 | ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, |
455 | unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) | |
456 | { | |
457 | struct kiocb kiocb; | |
458 | ssize_t ret; | |
459 | ||
460 | init_sync_kiocb(&kiocb, filp); | |
461 | kiocb.ki_pos = *ppos; | |
462 | kiocb.ki_left = len; | |
463 | kiocb.ki_nbytes = len; | |
464 | ||
465 | for (;;) { | |
466 | ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); | |
467 | if (ret != -EIOCBRETRY) | |
468 | break; | |
469 | wait_on_retry_sync_kiocb(&kiocb); | |
470 | } | |
471 | ||
472 | if (ret == -EIOCBQUEUED) | |
473 | ret = wait_on_sync_kiocb(&kiocb); | |
474 | *ppos = kiocb.ki_pos; | |
475 | return ret; | |
476 | } | |
477 | ||
478 | /* Do it by hand, with file-ops */ | |
479 | ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, | |
480 | unsigned long nr_segs, loff_t *ppos, io_fn_t fn) | |
481 | { | |
482 | struct iovec *vector = iov; | |
483 | ssize_t ret = 0; | |
484 | ||
485 | while (nr_segs > 0) { | |
486 | void __user *base; | |
487 | size_t len; | |
488 | ssize_t nr; | |
489 | ||
490 | base = vector->iov_base; | |
491 | len = vector->iov_len; | |
492 | vector++; | |
493 | nr_segs--; | |
494 | ||
495 | nr = fn(filp, base, len, ppos); | |
496 | ||
497 | if (nr < 0) { | |
498 | if (!ret) | |
499 | ret = nr; | |
500 | break; | |
501 | } | |
502 | ret += nr; | |
503 | if (nr != len) | |
504 | break; | |
505 | } | |
506 | ||
507 | return ret; | |
508 | } | |
509 | ||
1da177e4 LT |
510 | /* A write operation does a read from user space and vice versa */ |
511 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) | |
512 | ||
513 | static ssize_t do_readv_writev(int type, struct file *file, | |
514 | const struct iovec __user * uvector, | |
515 | unsigned long nr_segs, loff_t *pos) | |
516 | { | |
1da177e4 LT |
517 | size_t tot_len; |
518 | struct iovec iovstack[UIO_FASTIOV]; | |
ee0b3e67 | 519 | struct iovec *iov = iovstack; |
1da177e4 LT |
520 | ssize_t ret; |
521 | int seg; | |
522 | io_fn_t fn; | |
523 | iov_fn_t fnv; | |
524 | ||
525 | /* | |
526 | * SuS says "The readv() function *may* fail if the iovcnt argument | |
527 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has | |
528 | * traditionally returned zero for zero segments, so... | |
529 | */ | |
530 | ret = 0; | |
531 | if (nr_segs == 0) | |
532 | goto out; | |
533 | ||
534 | /* | |
535 | * First get the "struct iovec" from user memory and | |
536 | * verify all the pointers | |
537 | */ | |
538 | ret = -EINVAL; | |
6cc6b122 | 539 | if (nr_segs > UIO_MAXIOV) |
1da177e4 LT |
540 | goto out; |
541 | if (!file->f_op) | |
542 | goto out; | |
543 | if (nr_segs > UIO_FASTIOV) { | |
544 | ret = -ENOMEM; | |
545 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); | |
546 | if (!iov) | |
547 | goto out; | |
548 | } | |
549 | ret = -EFAULT; | |
550 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) | |
551 | goto out; | |
552 | ||
553 | /* | |
554 | * Single unix specification: | |
555 | * We should -EINVAL if an element length is not >= 0 and fitting an | |
556 | * ssize_t. The total length is fitting an ssize_t | |
557 | * | |
558 | * Be careful here because iov_len is a size_t not an ssize_t | |
559 | */ | |
560 | tot_len = 0; | |
561 | ret = -EINVAL; | |
562 | for (seg = 0; seg < nr_segs; seg++) { | |
563 | void __user *buf = iov[seg].iov_base; | |
564 | ssize_t len = (ssize_t)iov[seg].iov_len; | |
565 | ||
1da177e4 LT |
566 | if (len < 0) /* size_t not fitting an ssize_t .. */ |
567 | goto out; | |
1f08ad02 DH |
568 | if (unlikely(!access_ok(vrfy_dir(type), buf, len))) |
569 | goto Efault; | |
1da177e4 LT |
570 | tot_len += len; |
571 | if ((ssize_t)tot_len < 0) /* maths overflow on the ssize_t */ | |
572 | goto out; | |
573 | } | |
574 | if (tot_len == 0) { | |
575 | ret = 0; | |
576 | goto out; | |
577 | } | |
578 | ||
579 | ret = rw_verify_area(type, file, pos, tot_len); | |
e28cc715 | 580 | if (ret < 0) |
411b67b4 KB |
581 | goto out; |
582 | ret = security_file_permission(file, type == READ ? MAY_READ : MAY_WRITE); | |
1da177e4 LT |
583 | if (ret) |
584 | goto out; | |
585 | ||
586 | fnv = NULL; | |
587 | if (type == READ) { | |
588 | fn = file->f_op->read; | |
ee0b3e67 | 589 | fnv = file->f_op->aio_read; |
1da177e4 LT |
590 | } else { |
591 | fn = (io_fn_t)file->f_op->write; | |
ee0b3e67 | 592 | fnv = file->f_op->aio_write; |
1da177e4 LT |
593 | } |
594 | ||
ee0b3e67 BP |
595 | if (fnv) |
596 | ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, | |
597 | pos, fnv); | |
598 | else | |
599 | ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); | |
1da177e4 | 600 | |
1da177e4 LT |
601 | out: |
602 | if (iov != iovstack) | |
603 | kfree(iov); | |
0eeca283 RL |
604 | if ((ret + (type == READ)) > 0) { |
605 | if (type == READ) | |
606 | fsnotify_access(file->f_dentry); | |
607 | else | |
608 | fsnotify_modify(file->f_dentry); | |
609 | } | |
1da177e4 LT |
610 | return ret; |
611 | Efault: | |
612 | ret = -EFAULT; | |
613 | goto out; | |
614 | } | |
615 | ||
616 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, | |
617 | unsigned long vlen, loff_t *pos) | |
618 | { | |
619 | if (!(file->f_mode & FMODE_READ)) | |
620 | return -EBADF; | |
ee0b3e67 | 621 | if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read)) |
1da177e4 LT |
622 | return -EINVAL; |
623 | ||
624 | return do_readv_writev(READ, file, vec, vlen, pos); | |
625 | } | |
626 | ||
627 | EXPORT_SYMBOL(vfs_readv); | |
628 | ||
629 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, | |
630 | unsigned long vlen, loff_t *pos) | |
631 | { | |
632 | if (!(file->f_mode & FMODE_WRITE)) | |
633 | return -EBADF; | |
ee0b3e67 | 634 | if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write)) |
1da177e4 LT |
635 | return -EINVAL; |
636 | ||
637 | return do_readv_writev(WRITE, file, vec, vlen, pos); | |
638 | } | |
639 | ||
640 | EXPORT_SYMBOL(vfs_writev); | |
641 | ||
642 | asmlinkage ssize_t | |
643 | sys_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) | |
644 | { | |
645 | struct file *file; | |
646 | ssize_t ret = -EBADF; | |
647 | int fput_needed; | |
648 | ||
649 | file = fget_light(fd, &fput_needed); | |
650 | if (file) { | |
651 | loff_t pos = file_pos_read(file); | |
652 | ret = vfs_readv(file, vec, vlen, &pos); | |
653 | file_pos_write(file, pos); | |
654 | fput_light(file, fput_needed); | |
655 | } | |
656 | ||
657 | if (ret > 0) | |
658 | current->rchar += ret; | |
659 | current->syscr++; | |
660 | return ret; | |
661 | } | |
662 | ||
663 | asmlinkage ssize_t | |
664 | sys_writev(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) | |
665 | { | |
666 | struct file *file; | |
667 | ssize_t ret = -EBADF; | |
668 | int fput_needed; | |
669 | ||
670 | file = fget_light(fd, &fput_needed); | |
671 | if (file) { | |
672 | loff_t pos = file_pos_read(file); | |
673 | ret = vfs_writev(file, vec, vlen, &pos); | |
674 | file_pos_write(file, pos); | |
675 | fput_light(file, fput_needed); | |
676 | } | |
677 | ||
678 | if (ret > 0) | |
679 | current->wchar += ret; | |
680 | current->syscw++; | |
681 | return ret; | |
682 | } | |
683 | ||
684 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, | |
685 | size_t count, loff_t max) | |
686 | { | |
687 | struct file * in_file, * out_file; | |
688 | struct inode * in_inode, * out_inode; | |
689 | loff_t pos; | |
690 | ssize_t retval; | |
691 | int fput_needed_in, fput_needed_out; | |
692 | ||
693 | /* | |
694 | * Get input file, and verify that it is ok.. | |
695 | */ | |
696 | retval = -EBADF; | |
697 | in_file = fget_light(in_fd, &fput_needed_in); | |
698 | if (!in_file) | |
699 | goto out; | |
700 | if (!(in_file->f_mode & FMODE_READ)) | |
701 | goto fput_in; | |
702 | retval = -EINVAL; | |
703 | in_inode = in_file->f_dentry->d_inode; | |
704 | if (!in_inode) | |
705 | goto fput_in; | |
706 | if (!in_file->f_op || !in_file->f_op->sendfile) | |
707 | goto fput_in; | |
708 | retval = -ESPIPE; | |
709 | if (!ppos) | |
710 | ppos = &in_file->f_pos; | |
711 | else | |
712 | if (!(in_file->f_mode & FMODE_PREAD)) | |
713 | goto fput_in; | |
714 | retval = rw_verify_area(READ, in_file, ppos, count); | |
e28cc715 | 715 | if (retval < 0) |
1da177e4 | 716 | goto fput_in; |
e28cc715 | 717 | count = retval; |
1da177e4 LT |
718 | |
719 | retval = security_file_permission (in_file, MAY_READ); | |
720 | if (retval) | |
721 | goto fput_in; | |
722 | ||
723 | /* | |
724 | * Get output file, and verify that it is ok.. | |
725 | */ | |
726 | retval = -EBADF; | |
727 | out_file = fget_light(out_fd, &fput_needed_out); | |
728 | if (!out_file) | |
729 | goto fput_in; | |
730 | if (!(out_file->f_mode & FMODE_WRITE)) | |
731 | goto fput_out; | |
732 | retval = -EINVAL; | |
733 | if (!out_file->f_op || !out_file->f_op->sendpage) | |
734 | goto fput_out; | |
735 | out_inode = out_file->f_dentry->d_inode; | |
736 | retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); | |
e28cc715 | 737 | if (retval < 0) |
1da177e4 | 738 | goto fput_out; |
e28cc715 | 739 | count = retval; |
1da177e4 LT |
740 | |
741 | retval = security_file_permission (out_file, MAY_WRITE); | |
742 | if (retval) | |
743 | goto fput_out; | |
744 | ||
745 | if (!max) | |
746 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); | |
747 | ||
748 | pos = *ppos; | |
749 | retval = -EINVAL; | |
750 | if (unlikely(pos < 0)) | |
751 | goto fput_out; | |
752 | if (unlikely(pos + count > max)) { | |
753 | retval = -EOVERFLOW; | |
754 | if (pos >= max) | |
755 | goto fput_out; | |
756 | count = max - pos; | |
757 | } | |
758 | ||
759 | retval = in_file->f_op->sendfile(in_file, ppos, count, file_send_actor, out_file); | |
760 | ||
761 | if (retval > 0) { | |
762 | current->rchar += retval; | |
763 | current->wchar += retval; | |
764 | } | |
765 | current->syscr++; | |
766 | current->syscw++; | |
767 | ||
768 | if (*ppos > max) | |
769 | retval = -EOVERFLOW; | |
770 | ||
771 | fput_out: | |
772 | fput_light(out_file, fput_needed_out); | |
773 | fput_in: | |
774 | fput_light(in_file, fput_needed_in); | |
775 | out: | |
776 | return retval; | |
777 | } | |
778 | ||
779 | asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t __user *offset, size_t count) | |
780 | { | |
781 | loff_t pos; | |
782 | off_t off; | |
783 | ssize_t ret; | |
784 | ||
785 | if (offset) { | |
786 | if (unlikely(get_user(off, offset))) | |
787 | return -EFAULT; | |
788 | pos = off; | |
789 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
790 | if (unlikely(put_user(pos, offset))) | |
791 | return -EFAULT; | |
792 | return ret; | |
793 | } | |
794 | ||
795 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
796 | } | |
797 | ||
798 | asmlinkage ssize_t sys_sendfile64(int out_fd, int in_fd, loff_t __user *offset, size_t count) | |
799 | { | |
800 | loff_t pos; | |
801 | ssize_t ret; | |
802 | ||
803 | if (offset) { | |
804 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
805 | return -EFAULT; | |
806 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
807 | if (unlikely(put_user(pos, offset))) | |
808 | return -EFAULT; | |
809 | return ret; | |
810 | } | |
811 | ||
812 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
813 | } |