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> |
d6b29d7c | 18 | #include <linux/splice.h> |
ee0b3e67 | 19 | #include "read_write.h" |
1da177e4 LT |
20 | |
21 | #include <asm/uaccess.h> | |
22 | #include <asm/unistd.h> | |
23 | ||
4b6f5d20 | 24 | const struct file_operations generic_ro_fops = { |
1da177e4 | 25 | .llseek = generic_file_llseek, |
543ade1f BP |
26 | .read = do_sync_read, |
27 | .aio_read = generic_file_aio_read, | |
1da177e4 | 28 | .mmap = generic_file_readonly_mmap, |
534f2aaa | 29 | .splice_read = generic_file_splice_read, |
1da177e4 LT |
30 | }; |
31 | ||
32 | EXPORT_SYMBOL(generic_ro_fops); | |
33 | ||
9465efc9 AK |
34 | loff_t |
35 | generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin) | |
1da177e4 | 36 | { |
16abef0e | 37 | loff_t retval; |
1da177e4 LT |
38 | struct inode *inode = file->f_mapping->host; |
39 | ||
1da177e4 | 40 | switch (origin) { |
7b8e8924 | 41 | case SEEK_END: |
1da177e4 LT |
42 | offset += inode->i_size; |
43 | break; | |
7b8e8924 | 44 | case SEEK_CUR: |
1da177e4 LT |
45 | offset += file->f_pos; |
46 | } | |
47 | retval = -EINVAL; | |
48 | if (offset>=0 && offset<=inode->i_sb->s_maxbytes) { | |
9465efc9 | 49 | /* Special lock needed here? */ |
1da177e4 LT |
50 | if (offset != file->f_pos) { |
51 | file->f_pos = offset; | |
52 | file->f_version = 0; | |
53 | } | |
54 | retval = offset; | |
55 | } | |
1da177e4 LT |
56 | return retval; |
57 | } | |
9465efc9 | 58 | EXPORT_SYMBOL(generic_file_llseek_unlocked); |
1da177e4 | 59 | |
9465efc9 | 60 | loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) |
1da177e4 | 61 | { |
9465efc9 AK |
62 | loff_t n; |
63 | mutex_lock(&file->f_dentry->d_inode->i_mutex); | |
64 | n = generic_file_llseek_unlocked(file, offset, origin); | |
65 | mutex_unlock(&file->f_dentry->d_inode->i_mutex); | |
66 | return n; | |
1da177e4 | 67 | } |
9465efc9 | 68 | EXPORT_SYMBOL(generic_file_llseek); |
1da177e4 LT |
69 | |
70 | loff_t no_llseek(struct file *file, loff_t offset, int origin) | |
71 | { | |
72 | return -ESPIPE; | |
73 | } | |
74 | EXPORT_SYMBOL(no_llseek); | |
75 | ||
76 | loff_t default_llseek(struct file *file, loff_t offset, int origin) | |
77 | { | |
16abef0e | 78 | loff_t retval; |
1da177e4 LT |
79 | |
80 | lock_kernel(); | |
81 | switch (origin) { | |
7b8e8924 | 82 | case SEEK_END: |
0f7fc9e4 | 83 | offset += i_size_read(file->f_path.dentry->d_inode); |
1da177e4 | 84 | break; |
7b8e8924 | 85 | case SEEK_CUR: |
1da177e4 LT |
86 | offset += file->f_pos; |
87 | } | |
88 | retval = -EINVAL; | |
89 | if (offset >= 0) { | |
90 | if (offset != file->f_pos) { | |
91 | file->f_pos = offset; | |
92 | file->f_version = 0; | |
93 | } | |
94 | retval = offset; | |
95 | } | |
96 | unlock_kernel(); | |
97 | return retval; | |
98 | } | |
99 | EXPORT_SYMBOL(default_llseek); | |
100 | ||
101 | loff_t vfs_llseek(struct file *file, loff_t offset, int origin) | |
102 | { | |
103 | loff_t (*fn)(struct file *, loff_t, int); | |
104 | ||
105 | fn = no_llseek; | |
106 | if (file->f_mode & FMODE_LSEEK) { | |
107 | fn = default_llseek; | |
108 | if (file->f_op && file->f_op->llseek) | |
109 | fn = file->f_op->llseek; | |
110 | } | |
111 | return fn(file, offset, origin); | |
112 | } | |
113 | EXPORT_SYMBOL(vfs_llseek); | |
114 | ||
115 | asmlinkage off_t sys_lseek(unsigned int fd, off_t offset, unsigned int origin) | |
116 | { | |
117 | off_t retval; | |
118 | struct file * file; | |
119 | int fput_needed; | |
120 | ||
121 | retval = -EBADF; | |
122 | file = fget_light(fd, &fput_needed); | |
123 | if (!file) | |
124 | goto bad; | |
125 | ||
126 | retval = -EINVAL; | |
1ae7075b | 127 | if (origin <= SEEK_MAX) { |
1da177e4 LT |
128 | loff_t res = vfs_llseek(file, offset, origin); |
129 | retval = res; | |
130 | if (res != (loff_t)retval) | |
131 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ | |
132 | } | |
133 | fput_light(file, fput_needed); | |
134 | bad: | |
135 | return retval; | |
136 | } | |
137 | ||
138 | #ifdef __ARCH_WANT_SYS_LLSEEK | |
139 | asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high, | |
140 | unsigned long offset_low, loff_t __user * result, | |
141 | unsigned int origin) | |
142 | { | |
143 | int retval; | |
144 | struct file * file; | |
145 | loff_t offset; | |
146 | int fput_needed; | |
147 | ||
148 | retval = -EBADF; | |
149 | file = fget_light(fd, &fput_needed); | |
150 | if (!file) | |
151 | goto bad; | |
152 | ||
153 | retval = -EINVAL; | |
1ae7075b | 154 | if (origin > SEEK_MAX) |
1da177e4 LT |
155 | goto out_putf; |
156 | ||
157 | offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low, | |
158 | origin); | |
159 | ||
160 | retval = (int)offset; | |
161 | if (offset >= 0) { | |
162 | retval = -EFAULT; | |
163 | if (!copy_to_user(result, &offset, sizeof(offset))) | |
164 | retval = 0; | |
165 | } | |
166 | out_putf: | |
167 | fput_light(file, fput_needed); | |
168 | bad: | |
169 | return retval; | |
170 | } | |
171 | #endif | |
172 | ||
e28cc715 LT |
173 | /* |
174 | * rw_verify_area doesn't like huge counts. We limit | |
175 | * them to something that fits in "int" so that others | |
176 | * won't have to do range checks all the time. | |
177 | */ | |
178 | #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK) | |
1da177e4 LT |
179 | |
180 | int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count) | |
181 | { | |
182 | struct inode *inode; | |
183 | loff_t pos; | |
c43e259c | 184 | int retval = -EINVAL; |
1da177e4 | 185 | |
163da958 | 186 | inode = file->f_path.dentry->d_inode; |
e28cc715 | 187 | if (unlikely((ssize_t) count < 0)) |
c43e259c | 188 | return retval; |
1da177e4 LT |
189 | pos = *ppos; |
190 | if (unlikely((pos < 0) || (loff_t) (pos + count) < 0)) | |
c43e259c | 191 | return retval; |
1da177e4 | 192 | |
a16877ca | 193 | if (unlikely(inode->i_flock && mandatory_lock(inode))) { |
c43e259c | 194 | retval = locks_mandatory_area( |
e28cc715 LT |
195 | read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, |
196 | inode, file, pos, count); | |
197 | if (retval < 0) | |
198 | return retval; | |
199 | } | |
c43e259c JM |
200 | retval = security_file_permission(file, |
201 | read_write == READ ? MAY_READ : MAY_WRITE); | |
202 | if (retval) | |
203 | return retval; | |
e28cc715 | 204 | return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; |
1da177e4 LT |
205 | } |
206 | ||
63e68809 BL |
207 | static void wait_on_retry_sync_kiocb(struct kiocb *iocb) |
208 | { | |
209 | set_current_state(TASK_UNINTERRUPTIBLE); | |
210 | if (!kiocbIsKicked(iocb)) | |
211 | schedule(); | |
212 | else | |
213 | kiocbClearKicked(iocb); | |
214 | __set_current_state(TASK_RUNNING); | |
215 | } | |
216 | ||
1da177e4 LT |
217 | ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
218 | { | |
027445c3 | 219 | struct iovec iov = { .iov_base = buf, .iov_len = len }; |
1da177e4 LT |
220 | struct kiocb kiocb; |
221 | ssize_t ret; | |
222 | ||
223 | init_sync_kiocb(&kiocb, filp); | |
224 | kiocb.ki_pos = *ppos; | |
027445c3 BP |
225 | kiocb.ki_left = len; |
226 | ||
227 | for (;;) { | |
228 | ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); | |
229 | if (ret != -EIOCBRETRY) | |
230 | break; | |
63e68809 | 231 | wait_on_retry_sync_kiocb(&kiocb); |
027445c3 | 232 | } |
63e68809 | 233 | |
1da177e4 LT |
234 | if (-EIOCBQUEUED == ret) |
235 | ret = wait_on_sync_kiocb(&kiocb); | |
236 | *ppos = kiocb.ki_pos; | |
237 | return ret; | |
238 | } | |
239 | ||
240 | EXPORT_SYMBOL(do_sync_read); | |
241 | ||
242 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) | |
243 | { | |
244 | ssize_t ret; | |
245 | ||
246 | if (!(file->f_mode & FMODE_READ)) | |
247 | return -EBADF; | |
248 | if (!file->f_op || (!file->f_op->read && !file->f_op->aio_read)) | |
249 | return -EINVAL; | |
250 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) | |
251 | return -EFAULT; | |
252 | ||
253 | ret = rw_verify_area(READ, file, pos, count); | |
e28cc715 LT |
254 | if (ret >= 0) { |
255 | count = ret; | |
c43e259c JM |
256 | if (file->f_op->read) |
257 | ret = file->f_op->read(file, buf, count, pos); | |
258 | else | |
259 | ret = do_sync_read(file, buf, count, pos); | |
260 | if (ret > 0) { | |
261 | fsnotify_access(file->f_path.dentry); | |
262 | add_rchar(current, ret); | |
1da177e4 | 263 | } |
c43e259c | 264 | inc_syscr(current); |
1da177e4 LT |
265 | } |
266 | ||
267 | return ret; | |
268 | } | |
269 | ||
270 | EXPORT_SYMBOL(vfs_read); | |
271 | ||
272 | ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) | |
273 | { | |
027445c3 | 274 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; |
1da177e4 LT |
275 | struct kiocb kiocb; |
276 | ssize_t ret; | |
277 | ||
278 | init_sync_kiocb(&kiocb, filp); | |
279 | kiocb.ki_pos = *ppos; | |
027445c3 BP |
280 | kiocb.ki_left = len; |
281 | ||
282 | for (;;) { | |
283 | ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); | |
284 | if (ret != -EIOCBRETRY) | |
285 | break; | |
63e68809 | 286 | wait_on_retry_sync_kiocb(&kiocb); |
027445c3 | 287 | } |
63e68809 | 288 | |
1da177e4 LT |
289 | if (-EIOCBQUEUED == ret) |
290 | ret = wait_on_sync_kiocb(&kiocb); | |
291 | *ppos = kiocb.ki_pos; | |
292 | return ret; | |
293 | } | |
294 | ||
295 | EXPORT_SYMBOL(do_sync_write); | |
296 | ||
297 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) | |
298 | { | |
299 | ssize_t ret; | |
300 | ||
301 | if (!(file->f_mode & FMODE_WRITE)) | |
302 | return -EBADF; | |
303 | if (!file->f_op || (!file->f_op->write && !file->f_op->aio_write)) | |
304 | return -EINVAL; | |
305 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) | |
306 | return -EFAULT; | |
307 | ||
308 | ret = rw_verify_area(WRITE, file, pos, count); | |
e28cc715 LT |
309 | if (ret >= 0) { |
310 | count = ret; | |
c43e259c JM |
311 | if (file->f_op->write) |
312 | ret = file->f_op->write(file, buf, count, pos); | |
313 | else | |
314 | ret = do_sync_write(file, buf, count, pos); | |
315 | if (ret > 0) { | |
316 | fsnotify_modify(file->f_path.dentry); | |
317 | add_wchar(current, ret); | |
1da177e4 | 318 | } |
c43e259c | 319 | inc_syscw(current); |
1da177e4 LT |
320 | } |
321 | ||
322 | return ret; | |
323 | } | |
324 | ||
325 | EXPORT_SYMBOL(vfs_write); | |
326 | ||
327 | static inline loff_t file_pos_read(struct file *file) | |
328 | { | |
329 | return file->f_pos; | |
330 | } | |
331 | ||
332 | static inline void file_pos_write(struct file *file, loff_t pos) | |
333 | { | |
334 | file->f_pos = pos; | |
335 | } | |
336 | ||
337 | asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count) | |
338 | { | |
339 | struct file *file; | |
340 | ssize_t ret = -EBADF; | |
341 | int fput_needed; | |
342 | ||
343 | file = fget_light(fd, &fput_needed); | |
344 | if (file) { | |
345 | loff_t pos = file_pos_read(file); | |
346 | ret = vfs_read(file, buf, count, &pos); | |
347 | file_pos_write(file, pos); | |
348 | fput_light(file, fput_needed); | |
349 | } | |
350 | ||
351 | return ret; | |
352 | } | |
1da177e4 LT |
353 | |
354 | asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t count) | |
355 | { | |
356 | struct file *file; | |
357 | ssize_t ret = -EBADF; | |
358 | int fput_needed; | |
359 | ||
360 | file = fget_light(fd, &fput_needed); | |
361 | if (file) { | |
362 | loff_t pos = file_pos_read(file); | |
363 | ret = vfs_write(file, buf, count, &pos); | |
364 | file_pos_write(file, pos); | |
365 | fput_light(file, fput_needed); | |
366 | } | |
367 | ||
368 | return ret; | |
369 | } | |
370 | ||
371 | asmlinkage ssize_t sys_pread64(unsigned int fd, char __user *buf, | |
372 | size_t count, loff_t pos) | |
373 | { | |
374 | struct file *file; | |
375 | ssize_t ret = -EBADF; | |
376 | int fput_needed; | |
377 | ||
378 | if (pos < 0) | |
379 | return -EINVAL; | |
380 | ||
381 | file = fget_light(fd, &fput_needed); | |
382 | if (file) { | |
383 | ret = -ESPIPE; | |
384 | if (file->f_mode & FMODE_PREAD) | |
385 | ret = vfs_read(file, buf, count, &pos); | |
386 | fput_light(file, fput_needed); | |
387 | } | |
388 | ||
389 | return ret; | |
390 | } | |
391 | ||
392 | asmlinkage ssize_t sys_pwrite64(unsigned int fd, const char __user *buf, | |
393 | size_t count, loff_t pos) | |
394 | { | |
395 | struct file *file; | |
396 | ssize_t ret = -EBADF; | |
397 | int fput_needed; | |
398 | ||
399 | if (pos < 0) | |
400 | return -EINVAL; | |
401 | ||
402 | file = fget_light(fd, &fput_needed); | |
403 | if (file) { | |
404 | ret = -ESPIPE; | |
405 | if (file->f_mode & FMODE_PWRITE) | |
406 | ret = vfs_write(file, buf, count, &pos); | |
407 | fput_light(file, fput_needed); | |
408 | } | |
409 | ||
410 | return ret; | |
411 | } | |
412 | ||
413 | /* | |
414 | * Reduce an iovec's length in-place. Return the resulting number of segments | |
415 | */ | |
416 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) | |
417 | { | |
418 | unsigned long seg = 0; | |
419 | size_t len = 0; | |
420 | ||
421 | while (seg < nr_segs) { | |
422 | seg++; | |
423 | if (len + iov->iov_len >= to) { | |
424 | iov->iov_len = to - len; | |
425 | break; | |
426 | } | |
427 | len += iov->iov_len; | |
428 | iov++; | |
429 | } | |
430 | return seg; | |
431 | } | |
19295529 | 432 | EXPORT_SYMBOL(iov_shorten); |
1da177e4 | 433 | |
ee0b3e67 BP |
434 | ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, |
435 | unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) | |
436 | { | |
437 | struct kiocb kiocb; | |
438 | ssize_t ret; | |
439 | ||
440 | init_sync_kiocb(&kiocb, filp); | |
441 | kiocb.ki_pos = *ppos; | |
442 | kiocb.ki_left = len; | |
443 | kiocb.ki_nbytes = len; | |
444 | ||
445 | for (;;) { | |
446 | ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); | |
447 | if (ret != -EIOCBRETRY) | |
448 | break; | |
449 | wait_on_retry_sync_kiocb(&kiocb); | |
450 | } | |
451 | ||
452 | if (ret == -EIOCBQUEUED) | |
453 | ret = wait_on_sync_kiocb(&kiocb); | |
454 | *ppos = kiocb.ki_pos; | |
455 | return ret; | |
456 | } | |
457 | ||
458 | /* Do it by hand, with file-ops */ | |
459 | ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, | |
460 | unsigned long nr_segs, loff_t *ppos, io_fn_t fn) | |
461 | { | |
462 | struct iovec *vector = iov; | |
463 | ssize_t ret = 0; | |
464 | ||
465 | while (nr_segs > 0) { | |
466 | void __user *base; | |
467 | size_t len; | |
468 | ssize_t nr; | |
469 | ||
470 | base = vector->iov_base; | |
471 | len = vector->iov_len; | |
472 | vector++; | |
473 | nr_segs--; | |
474 | ||
475 | nr = fn(filp, base, len, ppos); | |
476 | ||
477 | if (nr < 0) { | |
478 | if (!ret) | |
479 | ret = nr; | |
480 | break; | |
481 | } | |
482 | ret += nr; | |
483 | if (nr != len) | |
484 | break; | |
485 | } | |
486 | ||
487 | return ret; | |
488 | } | |
489 | ||
1da177e4 LT |
490 | /* A write operation does a read from user space and vice versa */ |
491 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) | |
492 | ||
eed4e51f BP |
493 | ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, |
494 | unsigned long nr_segs, unsigned long fast_segs, | |
495 | struct iovec *fast_pointer, | |
496 | struct iovec **ret_pointer) | |
497 | { | |
498 | unsigned long seg; | |
499 | ssize_t ret; | |
500 | struct iovec *iov = fast_pointer; | |
501 | ||
502 | /* | |
503 | * SuS says "The readv() function *may* fail if the iovcnt argument | |
504 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has | |
505 | * traditionally returned zero for zero segments, so... | |
506 | */ | |
507 | if (nr_segs == 0) { | |
508 | ret = 0; | |
509 | goto out; | |
510 | } | |
511 | ||
512 | /* | |
513 | * First get the "struct iovec" from user memory and | |
514 | * verify all the pointers | |
515 | */ | |
516 | if (nr_segs > UIO_MAXIOV) { | |
517 | ret = -EINVAL; | |
518 | goto out; | |
519 | } | |
520 | if (nr_segs > fast_segs) { | |
521 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); | |
522 | if (iov == NULL) { | |
523 | ret = -ENOMEM; | |
524 | goto out; | |
525 | } | |
526 | } | |
527 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { | |
528 | ret = -EFAULT; | |
529 | goto out; | |
530 | } | |
531 | ||
532 | /* | |
533 | * According to the Single Unix Specification we should return EINVAL | |
534 | * if an element length is < 0 when cast to ssize_t or if the | |
535 | * total length would overflow the ssize_t return value of the | |
536 | * system call. | |
537 | */ | |
538 | ret = 0; | |
539 | for (seg = 0; seg < nr_segs; seg++) { | |
540 | void __user *buf = iov[seg].iov_base; | |
541 | ssize_t len = (ssize_t)iov[seg].iov_len; | |
542 | ||
543 | /* see if we we're about to use an invalid len or if | |
544 | * it's about to overflow ssize_t */ | |
545 | if (len < 0 || (ret + len < ret)) { | |
546 | ret = -EINVAL; | |
547 | goto out; | |
548 | } | |
549 | if (unlikely(!access_ok(vrfy_dir(type), buf, len))) { | |
550 | ret = -EFAULT; | |
551 | goto out; | |
552 | } | |
553 | ||
554 | ret += len; | |
555 | } | |
556 | out: | |
557 | *ret_pointer = iov; | |
558 | return ret; | |
559 | } | |
560 | ||
1da177e4 LT |
561 | static ssize_t do_readv_writev(int type, struct file *file, |
562 | const struct iovec __user * uvector, | |
563 | unsigned long nr_segs, loff_t *pos) | |
564 | { | |
1da177e4 LT |
565 | size_t tot_len; |
566 | struct iovec iovstack[UIO_FASTIOV]; | |
ee0b3e67 | 567 | struct iovec *iov = iovstack; |
1da177e4 | 568 | ssize_t ret; |
1da177e4 LT |
569 | io_fn_t fn; |
570 | iov_fn_t fnv; | |
571 | ||
eed4e51f BP |
572 | if (!file->f_op) { |
573 | ret = -EINVAL; | |
1da177e4 | 574 | goto out; |
1da177e4 | 575 | } |
1da177e4 | 576 | |
eed4e51f BP |
577 | ret = rw_copy_check_uvector(type, uvector, nr_segs, |
578 | ARRAY_SIZE(iovstack), iovstack, &iov); | |
579 | if (ret <= 0) | |
1da177e4 | 580 | goto out; |
1da177e4 | 581 | |
eed4e51f | 582 | tot_len = ret; |
1da177e4 | 583 | ret = rw_verify_area(type, file, pos, tot_len); |
e28cc715 | 584 | if (ret < 0) |
411b67b4 | 585 | goto out; |
1da177e4 LT |
586 | |
587 | fnv = NULL; | |
588 | if (type == READ) { | |
589 | fn = file->f_op->read; | |
ee0b3e67 | 590 | fnv = file->f_op->aio_read; |
1da177e4 LT |
591 | } else { |
592 | fn = (io_fn_t)file->f_op->write; | |
ee0b3e67 | 593 | fnv = file->f_op->aio_write; |
1da177e4 LT |
594 | } |
595 | ||
ee0b3e67 BP |
596 | if (fnv) |
597 | ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, | |
598 | pos, fnv); | |
599 | else | |
600 | ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); | |
1da177e4 | 601 | |
1da177e4 LT |
602 | out: |
603 | if (iov != iovstack) | |
604 | kfree(iov); | |
0eeca283 RL |
605 | if ((ret + (type == READ)) > 0) { |
606 | if (type == READ) | |
0f7fc9e4 | 607 | fsnotify_access(file->f_path.dentry); |
0eeca283 | 608 | else |
0f7fc9e4 | 609 | fsnotify_modify(file->f_path.dentry); |
0eeca283 | 610 | } |
1da177e4 | 611 | return ret; |
1da177e4 LT |
612 | } |
613 | ||
614 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, | |
615 | unsigned long vlen, loff_t *pos) | |
616 | { | |
617 | if (!(file->f_mode & FMODE_READ)) | |
618 | return -EBADF; | |
ee0b3e67 | 619 | if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read)) |
1da177e4 LT |
620 | return -EINVAL; |
621 | ||
622 | return do_readv_writev(READ, file, vec, vlen, pos); | |
623 | } | |
624 | ||
625 | EXPORT_SYMBOL(vfs_readv); | |
626 | ||
627 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, | |
628 | unsigned long vlen, loff_t *pos) | |
629 | { | |
630 | if (!(file->f_mode & FMODE_WRITE)) | |
631 | return -EBADF; | |
ee0b3e67 | 632 | if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write)) |
1da177e4 LT |
633 | return -EINVAL; |
634 | ||
635 | return do_readv_writev(WRITE, file, vec, vlen, pos); | |
636 | } | |
637 | ||
638 | EXPORT_SYMBOL(vfs_writev); | |
639 | ||
640 | asmlinkage ssize_t | |
641 | sys_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) | |
642 | { | |
643 | struct file *file; | |
644 | ssize_t ret = -EBADF; | |
645 | int fput_needed; | |
646 | ||
647 | file = fget_light(fd, &fput_needed); | |
648 | if (file) { | |
649 | loff_t pos = file_pos_read(file); | |
650 | ret = vfs_readv(file, vec, vlen, &pos); | |
651 | file_pos_write(file, pos); | |
652 | fput_light(file, fput_needed); | |
653 | } | |
654 | ||
655 | if (ret > 0) | |
4b98d11b AD |
656 | add_rchar(current, ret); |
657 | inc_syscr(current); | |
1da177e4 LT |
658 | return ret; |
659 | } | |
660 | ||
661 | asmlinkage ssize_t | |
662 | sys_writev(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) | |
663 | { | |
664 | struct file *file; | |
665 | ssize_t ret = -EBADF; | |
666 | int fput_needed; | |
667 | ||
668 | file = fget_light(fd, &fput_needed); | |
669 | if (file) { | |
670 | loff_t pos = file_pos_read(file); | |
671 | ret = vfs_writev(file, vec, vlen, &pos); | |
672 | file_pos_write(file, pos); | |
673 | fput_light(file, fput_needed); | |
674 | } | |
675 | ||
676 | if (ret > 0) | |
4b98d11b AD |
677 | add_wchar(current, ret); |
678 | inc_syscw(current); | |
1da177e4 LT |
679 | return ret; |
680 | } | |
681 | ||
682 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, | |
683 | size_t count, loff_t max) | |
684 | { | |
685 | struct file * in_file, * out_file; | |
686 | struct inode * in_inode, * out_inode; | |
687 | loff_t pos; | |
688 | ssize_t retval; | |
534f2aaa | 689 | int fput_needed_in, fput_needed_out, fl; |
1da177e4 LT |
690 | |
691 | /* | |
692 | * Get input file, and verify that it is ok.. | |
693 | */ | |
694 | retval = -EBADF; | |
695 | in_file = fget_light(in_fd, &fput_needed_in); | |
696 | if (!in_file) | |
697 | goto out; | |
698 | if (!(in_file->f_mode & FMODE_READ)) | |
699 | goto fput_in; | |
700 | retval = -EINVAL; | |
0f7fc9e4 | 701 | in_inode = in_file->f_path.dentry->d_inode; |
1da177e4 LT |
702 | if (!in_inode) |
703 | goto fput_in; | |
d96e6e71 | 704 | if (!in_file->f_op || !in_file->f_op->splice_read) |
1da177e4 LT |
705 | goto fput_in; |
706 | retval = -ESPIPE; | |
707 | if (!ppos) | |
708 | ppos = &in_file->f_pos; | |
709 | else | |
710 | if (!(in_file->f_mode & FMODE_PREAD)) | |
711 | goto fput_in; | |
712 | retval = rw_verify_area(READ, in_file, ppos, count); | |
e28cc715 | 713 | if (retval < 0) |
1da177e4 | 714 | goto fput_in; |
e28cc715 | 715 | count = retval; |
1da177e4 | 716 | |
1da177e4 LT |
717 | /* |
718 | * Get output file, and verify that it is ok.. | |
719 | */ | |
720 | retval = -EBADF; | |
721 | out_file = fget_light(out_fd, &fput_needed_out); | |
722 | if (!out_file) | |
723 | goto fput_in; | |
724 | if (!(out_file->f_mode & FMODE_WRITE)) | |
725 | goto fput_out; | |
726 | retval = -EINVAL; | |
727 | if (!out_file->f_op || !out_file->f_op->sendpage) | |
728 | goto fput_out; | |
0f7fc9e4 | 729 | out_inode = out_file->f_path.dentry->d_inode; |
1da177e4 | 730 | retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); |
e28cc715 | 731 | if (retval < 0) |
1da177e4 | 732 | goto fput_out; |
e28cc715 | 733 | count = retval; |
1da177e4 | 734 | |
1da177e4 LT |
735 | if (!max) |
736 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); | |
737 | ||
738 | pos = *ppos; | |
739 | retval = -EINVAL; | |
740 | if (unlikely(pos < 0)) | |
741 | goto fput_out; | |
742 | if (unlikely(pos + count > max)) { | |
743 | retval = -EOVERFLOW; | |
744 | if (pos >= max) | |
745 | goto fput_out; | |
746 | count = max - pos; | |
747 | } | |
748 | ||
d96e6e71 | 749 | fl = 0; |
534f2aaa | 750 | #if 0 |
d96e6e71 JA |
751 | /* |
752 | * We need to debate whether we can enable this or not. The | |
753 | * man page documents EAGAIN return for the output at least, | |
754 | * and the application is arguably buggy if it doesn't expect | |
755 | * EAGAIN on a non-blocking file descriptor. | |
756 | */ | |
757 | if (in_file->f_flags & O_NONBLOCK) | |
758 | fl = SPLICE_F_NONBLOCK; | |
534f2aaa | 759 | #endif |
d96e6e71 | 760 | retval = do_splice_direct(in_file, ppos, out_file, count, fl); |
1da177e4 LT |
761 | |
762 | if (retval > 0) { | |
4b98d11b AD |
763 | add_rchar(current, retval); |
764 | add_wchar(current, retval); | |
1da177e4 | 765 | } |
1da177e4 | 766 | |
4b98d11b AD |
767 | inc_syscr(current); |
768 | inc_syscw(current); | |
1da177e4 LT |
769 | if (*ppos > max) |
770 | retval = -EOVERFLOW; | |
771 | ||
772 | fput_out: | |
773 | fput_light(out_file, fput_needed_out); | |
774 | fput_in: | |
775 | fput_light(in_file, fput_needed_in); | |
776 | out: | |
777 | return retval; | |
778 | } | |
779 | ||
780 | asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t __user *offset, size_t count) | |
781 | { | |
782 | loff_t pos; | |
783 | off_t off; | |
784 | ssize_t ret; | |
785 | ||
786 | if (offset) { | |
787 | if (unlikely(get_user(off, offset))) | |
788 | return -EFAULT; | |
789 | pos = off; | |
790 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
791 | if (unlikely(put_user(pos, offset))) | |
792 | return -EFAULT; | |
793 | return ret; | |
794 | } | |
795 | ||
796 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
797 | } | |
798 | ||
799 | asmlinkage ssize_t sys_sendfile64(int out_fd, int in_fd, loff_t __user *offset, size_t count) | |
800 | { | |
801 | loff_t pos; | |
802 | ssize_t ret; | |
803 | ||
804 | if (offset) { | |
805 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
806 | return -EFAULT; | |
807 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
808 | if (unlikely(put_user(pos, offset))) | |
809 | return -EFAULT; | |
810 | return ret; | |
811 | } | |
812 | ||
813 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
814 | } |