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Source at commit b05a5adf03613de371c77c3235f7d970d7cd0c71 created 13 years 1 month ago. By Lars-Peter Clausen, NAND: Optimize reading the eec data for the JZ4740 (evil hack) | |
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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/fsnotify.h> |
13 | #include <linux/security.h> |
14 | #include <linux/module.h> |
15 | #include <linux/syscalls.h> |
16 | #include <linux/pagemap.h> |
17 | #include <linux/splice.h> |
18 | #include "read_write.h" |
19 | |
20 | #include <asm/uaccess.h> |
21 | #include <asm/unistd.h> |
22 | |
23 | const struct file_operations generic_ro_fops = { |
24 | .llseek = generic_file_llseek, |
25 | .read = do_sync_read, |
26 | .aio_read = generic_file_aio_read, |
27 | .mmap = generic_file_readonly_mmap, |
28 | .splice_read = generic_file_splice_read, |
29 | }; |
30 | |
31 | EXPORT_SYMBOL(generic_ro_fops); |
32 | |
33 | static inline int unsigned_offsets(struct file *file) |
34 | { |
35 | return file->f_mode & FMODE_UNSIGNED_OFFSET; |
36 | } |
37 | |
38 | /** |
39 | * generic_file_llseek_unlocked - lockless generic llseek implementation |
40 | * @file: file structure to seek on |
41 | * @offset: file offset to seek to |
42 | * @origin: type of seek |
43 | * |
44 | * Updates the file offset to the value specified by @offset and @origin. |
45 | * Locking must be provided by the caller. |
46 | */ |
47 | loff_t |
48 | generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin) |
49 | { |
50 | struct inode *inode = file->f_mapping->host; |
51 | |
52 | switch (origin) { |
53 | case SEEK_END: |
54 | offset += inode->i_size; |
55 | break; |
56 | case SEEK_CUR: |
57 | /* |
58 | * Here we special-case the lseek(fd, 0, SEEK_CUR) |
59 | * position-querying operation. Avoid rewriting the "same" |
60 | * f_pos value back to the file because a concurrent read(), |
61 | * write() or lseek() might have altered it |
62 | */ |
63 | if (offset == 0) |
64 | return file->f_pos; |
65 | offset += file->f_pos; |
66 | break; |
67 | } |
68 | |
69 | if (offset < 0 && !unsigned_offsets(file)) |
70 | return -EINVAL; |
71 | if (offset > inode->i_sb->s_maxbytes) |
72 | return -EINVAL; |
73 | |
74 | /* Special lock needed here? */ |
75 | if (offset != file->f_pos) { |
76 | file->f_pos = offset; |
77 | file->f_version = 0; |
78 | } |
79 | |
80 | return offset; |
81 | } |
82 | EXPORT_SYMBOL(generic_file_llseek_unlocked); |
83 | |
84 | /** |
85 | * generic_file_llseek - generic llseek implementation for regular files |
86 | * @file: file structure to seek on |
87 | * @offset: file offset to seek to |
88 | * @origin: type of seek |
89 | * |
90 | * This is a generic implemenation of ->llseek useable for all normal local |
91 | * filesystems. It just updates the file offset to the value specified by |
92 | * @offset and @origin under i_mutex. |
93 | */ |
94 | loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) |
95 | { |
96 | loff_t rval; |
97 | |
98 | mutex_lock(&file->f_dentry->d_inode->i_mutex); |
99 | rval = generic_file_llseek_unlocked(file, offset, origin); |
100 | mutex_unlock(&file->f_dentry->d_inode->i_mutex); |
101 | |
102 | return rval; |
103 | } |
104 | EXPORT_SYMBOL(generic_file_llseek); |
105 | |
106 | /** |
107 | * noop_llseek - No Operation Performed llseek implementation |
108 | * @file: file structure to seek on |
109 | * @offset: file offset to seek to |
110 | * @origin: type of seek |
111 | * |
112 | * This is an implementation of ->llseek useable for the rare special case when |
113 | * userspace expects the seek to succeed but the (device) file is actually not |
114 | * able to perform the seek. In this case you use noop_llseek() instead of |
115 | * falling back to the default implementation of ->llseek. |
116 | */ |
117 | loff_t noop_llseek(struct file *file, loff_t offset, int origin) |
118 | { |
119 | return file->f_pos; |
120 | } |
121 | EXPORT_SYMBOL(noop_llseek); |
122 | |
123 | loff_t no_llseek(struct file *file, loff_t offset, int origin) |
124 | { |
125 | return -ESPIPE; |
126 | } |
127 | EXPORT_SYMBOL(no_llseek); |
128 | |
129 | loff_t default_llseek(struct file *file, loff_t offset, int origin) |
130 | { |
131 | loff_t retval; |
132 | |
133 | mutex_lock(&file->f_dentry->d_inode->i_mutex); |
134 | switch (origin) { |
135 | case SEEK_END: |
136 | offset += i_size_read(file->f_path.dentry->d_inode); |
137 | break; |
138 | case SEEK_CUR: |
139 | if (offset == 0) { |
140 | retval = file->f_pos; |
141 | goto out; |
142 | } |
143 | offset += file->f_pos; |
144 | } |
145 | retval = -EINVAL; |
146 | if (offset >= 0 || unsigned_offsets(file)) { |
147 | if (offset != file->f_pos) { |
148 | file->f_pos = offset; |
149 | file->f_version = 0; |
150 | } |
151 | retval = offset; |
152 | } |
153 | out: |
154 | mutex_unlock(&file->f_dentry->d_inode->i_mutex); |
155 | return retval; |
156 | } |
157 | EXPORT_SYMBOL(default_llseek); |
158 | |
159 | loff_t vfs_llseek(struct file *file, loff_t offset, int origin) |
160 | { |
161 | loff_t (*fn)(struct file *, loff_t, int); |
162 | |
163 | fn = no_llseek; |
164 | if (file->f_mode & FMODE_LSEEK) { |
165 | if (file->f_op && file->f_op->llseek) |
166 | fn = file->f_op->llseek; |
167 | } |
168 | return fn(file, offset, origin); |
169 | } |
170 | EXPORT_SYMBOL(vfs_llseek); |
171 | |
172 | SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, origin) |
173 | { |
174 | off_t retval; |
175 | struct file * file; |
176 | int fput_needed; |
177 | |
178 | retval = -EBADF; |
179 | file = fget_light(fd, &fput_needed); |
180 | if (!file) |
181 | goto bad; |
182 | |
183 | retval = -EINVAL; |
184 | if (origin <= SEEK_MAX) { |
185 | loff_t res = vfs_llseek(file, offset, origin); |
186 | retval = res; |
187 | if (res != (loff_t)retval) |
188 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ |
189 | } |
190 | fput_light(file, fput_needed); |
191 | bad: |
192 | return retval; |
193 | } |
194 | |
195 | #ifdef __ARCH_WANT_SYS_LLSEEK |
196 | SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, |
197 | unsigned long, offset_low, loff_t __user *, result, |
198 | unsigned int, origin) |
199 | { |
200 | int retval; |
201 | struct file * file; |
202 | loff_t offset; |
203 | int fput_needed; |
204 | |
205 | retval = -EBADF; |
206 | file = fget_light(fd, &fput_needed); |
207 | if (!file) |
208 | goto bad; |
209 | |
210 | retval = -EINVAL; |
211 | if (origin > SEEK_MAX) |
212 | goto out_putf; |
213 | |
214 | offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low, |
215 | origin); |
216 | |
217 | retval = (int)offset; |
218 | if (offset >= 0) { |
219 | retval = -EFAULT; |
220 | if (!copy_to_user(result, &offset, sizeof(offset))) |
221 | retval = 0; |
222 | } |
223 | out_putf: |
224 | fput_light(file, fput_needed); |
225 | bad: |
226 | return retval; |
227 | } |
228 | #endif |
229 | |
230 | |
231 | /* |
232 | * rw_verify_area doesn't like huge counts. We limit |
233 | * them to something that fits in "int" so that others |
234 | * won't have to do range checks all the time. |
235 | */ |
236 | int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count) |
237 | { |
238 | struct inode *inode; |
239 | loff_t pos; |
240 | int retval = -EINVAL; |
241 | |
242 | inode = file->f_path.dentry->d_inode; |
243 | if (unlikely((ssize_t) count < 0)) |
244 | return retval; |
245 | pos = *ppos; |
246 | if (unlikely(pos < 0)) { |
247 | if (!unsigned_offsets(file)) |
248 | return retval; |
249 | if (count >= -pos) /* both values are in 0..LLONG_MAX */ |
250 | return -EOVERFLOW; |
251 | } else if (unlikely((loff_t) (pos + count) < 0)) { |
252 | if (!unsigned_offsets(file)) |
253 | return retval; |
254 | } |
255 | |
256 | if (unlikely(inode->i_flock && mandatory_lock(inode))) { |
257 | retval = locks_mandatory_area( |
258 | read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, |
259 | inode, file, pos, count); |
260 | if (retval < 0) |
261 | return retval; |
262 | } |
263 | retval = security_file_permission(file, |
264 | read_write == READ ? MAY_READ : MAY_WRITE); |
265 | if (retval) |
266 | return retval; |
267 | return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; |
268 | } |
269 | |
270 | static void wait_on_retry_sync_kiocb(struct kiocb *iocb) |
271 | { |
272 | set_current_state(TASK_UNINTERRUPTIBLE); |
273 | if (!kiocbIsKicked(iocb)) |
274 | schedule(); |
275 | else |
276 | kiocbClearKicked(iocb); |
277 | __set_current_state(TASK_RUNNING); |
278 | } |
279 | |
280 | ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
281 | { |
282 | struct iovec iov = { .iov_base = buf, .iov_len = len }; |
283 | struct kiocb kiocb; |
284 | ssize_t ret; |
285 | |
286 | init_sync_kiocb(&kiocb, filp); |
287 | kiocb.ki_pos = *ppos; |
288 | kiocb.ki_left = len; |
289 | kiocb.ki_nbytes = len; |
290 | |
291 | for (;;) { |
292 | ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); |
293 | if (ret != -EIOCBRETRY) |
294 | break; |
295 | wait_on_retry_sync_kiocb(&kiocb); |
296 | } |
297 | |
298 | if (-EIOCBQUEUED == ret) |
299 | ret = wait_on_sync_kiocb(&kiocb); |
300 | *ppos = kiocb.ki_pos; |
301 | return ret; |
302 | } |
303 | |
304 | EXPORT_SYMBOL(do_sync_read); |
305 | |
306 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) |
307 | { |
308 | ssize_t ret; |
309 | |
310 | if (!(file->f_mode & FMODE_READ)) |
311 | return -EBADF; |
312 | if (!file->f_op || (!file->f_op->read && !file->f_op->aio_read)) |
313 | return -EINVAL; |
314 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) |
315 | return -EFAULT; |
316 | |
317 | ret = rw_verify_area(READ, file, pos, count); |
318 | if (ret >= 0) { |
319 | count = ret; |
320 | if (file->f_op->read) |
321 | ret = file->f_op->read(file, buf, count, pos); |
322 | else |
323 | ret = do_sync_read(file, buf, count, pos); |
324 | if (ret > 0) { |
325 | fsnotify_access(file); |
326 | add_rchar(current, ret); |
327 | } |
328 | inc_syscr(current); |
329 | } |
330 | |
331 | return ret; |
332 | } |
333 | |
334 | EXPORT_SYMBOL(vfs_read); |
335 | |
336 | ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) |
337 | { |
338 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; |
339 | struct kiocb kiocb; |
340 | ssize_t ret; |
341 | |
342 | init_sync_kiocb(&kiocb, filp); |
343 | kiocb.ki_pos = *ppos; |
344 | kiocb.ki_left = len; |
345 | kiocb.ki_nbytes = len; |
346 | |
347 | for (;;) { |
348 | ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); |
349 | if (ret != -EIOCBRETRY) |
350 | break; |
351 | wait_on_retry_sync_kiocb(&kiocb); |
352 | } |
353 | |
354 | if (-EIOCBQUEUED == ret) |
355 | ret = wait_on_sync_kiocb(&kiocb); |
356 | *ppos = kiocb.ki_pos; |
357 | return ret; |
358 | } |
359 | |
360 | EXPORT_SYMBOL(do_sync_write); |
361 | |
362 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
363 | { |
364 | ssize_t ret; |
365 | |
366 | if (!(file->f_mode & FMODE_WRITE)) |
367 | return -EBADF; |
368 | if (!file->f_op || (!file->f_op->write && !file->f_op->aio_write)) |
369 | return -EINVAL; |
370 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) |
371 | return -EFAULT; |
372 | |
373 | ret = rw_verify_area(WRITE, file, pos, count); |
374 | if (ret >= 0) { |
375 | count = ret; |
376 | if (file->f_op->write) |
377 | ret = file->f_op->write(file, buf, count, pos); |
378 | else |
379 | ret = do_sync_write(file, buf, count, pos); |
380 | if (ret > 0) { |
381 | fsnotify_modify(file); |
382 | add_wchar(current, ret); |
383 | } |
384 | inc_syscw(current); |
385 | } |
386 | |
387 | return ret; |
388 | } |
389 | |
390 | EXPORT_SYMBOL(vfs_write); |
391 | |
392 | static inline loff_t file_pos_read(struct file *file) |
393 | { |
394 | return file->f_pos; |
395 | } |
396 | |
397 | static inline void file_pos_write(struct file *file, loff_t pos) |
398 | { |
399 | file->f_pos = pos; |
400 | } |
401 | |
402 | SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) |
403 | { |
404 | struct file *file; |
405 | ssize_t ret = -EBADF; |
406 | int fput_needed; |
407 | |
408 | file = fget_light(fd, &fput_needed); |
409 | if (file) { |
410 | loff_t pos = file_pos_read(file); |
411 | ret = vfs_read(file, buf, count, &pos); |
412 | file_pos_write(file, pos); |
413 | fput_light(file, fput_needed); |
414 | } |
415 | |
416 | return ret; |
417 | } |
418 | |
419 | SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, |
420 | size_t, count) |
421 | { |
422 | struct file *file; |
423 | ssize_t ret = -EBADF; |
424 | int fput_needed; |
425 | |
426 | file = fget_light(fd, &fput_needed); |
427 | if (file) { |
428 | loff_t pos = file_pos_read(file); |
429 | ret = vfs_write(file, buf, count, &pos); |
430 | file_pos_write(file, pos); |
431 | fput_light(file, fput_needed); |
432 | } |
433 | |
434 | return ret; |
435 | } |
436 | |
437 | SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf, |
438 | size_t count, loff_t pos) |
439 | { |
440 | struct file *file; |
441 | ssize_t ret = -EBADF; |
442 | int fput_needed; |
443 | |
444 | if (pos < 0) |
445 | return -EINVAL; |
446 | |
447 | file = fget_light(fd, &fput_needed); |
448 | if (file) { |
449 | ret = -ESPIPE; |
450 | if (file->f_mode & FMODE_PREAD) |
451 | ret = vfs_read(file, buf, count, &pos); |
452 | fput_light(file, fput_needed); |
453 | } |
454 | |
455 | return ret; |
456 | } |
457 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
458 | asmlinkage long SyS_pread64(long fd, long buf, long count, loff_t pos) |
459 | { |
460 | return SYSC_pread64((unsigned int) fd, (char __user *) buf, |
461 | (size_t) count, pos); |
462 | } |
463 | SYSCALL_ALIAS(sys_pread64, SyS_pread64); |
464 | #endif |
465 | |
466 | SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf, |
467 | size_t count, loff_t pos) |
468 | { |
469 | struct file *file; |
470 | ssize_t ret = -EBADF; |
471 | int fput_needed; |
472 | |
473 | if (pos < 0) |
474 | return -EINVAL; |
475 | |
476 | file = fget_light(fd, &fput_needed); |
477 | if (file) { |
478 | ret = -ESPIPE; |
479 | if (file->f_mode & FMODE_PWRITE) |
480 | ret = vfs_write(file, buf, count, &pos); |
481 | fput_light(file, fput_needed); |
482 | } |
483 | |
484 | return ret; |
485 | } |
486 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
487 | asmlinkage long SyS_pwrite64(long fd, long buf, long count, loff_t pos) |
488 | { |
489 | return SYSC_pwrite64((unsigned int) fd, (const char __user *) buf, |
490 | (size_t) count, pos); |
491 | } |
492 | SYSCALL_ALIAS(sys_pwrite64, SyS_pwrite64); |
493 | #endif |
494 | |
495 | /* |
496 | * Reduce an iovec's length in-place. Return the resulting number of segments |
497 | */ |
498 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) |
499 | { |
500 | unsigned long seg = 0; |
501 | size_t len = 0; |
502 | |
503 | while (seg < nr_segs) { |
504 | seg++; |
505 | if (len + iov->iov_len >= to) { |
506 | iov->iov_len = to - len; |
507 | break; |
508 | } |
509 | len += iov->iov_len; |
510 | iov++; |
511 | } |
512 | return seg; |
513 | } |
514 | EXPORT_SYMBOL(iov_shorten); |
515 | |
516 | ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, |
517 | unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) |
518 | { |
519 | struct kiocb kiocb; |
520 | ssize_t ret; |
521 | |
522 | init_sync_kiocb(&kiocb, filp); |
523 | kiocb.ki_pos = *ppos; |
524 | kiocb.ki_left = len; |
525 | kiocb.ki_nbytes = len; |
526 | |
527 | for (;;) { |
528 | ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); |
529 | if (ret != -EIOCBRETRY) |
530 | break; |
531 | wait_on_retry_sync_kiocb(&kiocb); |
532 | } |
533 | |
534 | if (ret == -EIOCBQUEUED) |
535 | ret = wait_on_sync_kiocb(&kiocb); |
536 | *ppos = kiocb.ki_pos; |
537 | return ret; |
538 | } |
539 | |
540 | /* Do it by hand, with file-ops */ |
541 | ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, |
542 | unsigned long nr_segs, loff_t *ppos, io_fn_t fn) |
543 | { |
544 | struct iovec *vector = iov; |
545 | ssize_t ret = 0; |
546 | |
547 | while (nr_segs > 0) { |
548 | void __user *base; |
549 | size_t len; |
550 | ssize_t nr; |
551 | |
552 | base = vector->iov_base; |
553 | len = vector->iov_len; |
554 | vector++; |
555 | nr_segs--; |
556 | |
557 | nr = fn(filp, base, len, ppos); |
558 | |
559 | if (nr < 0) { |
560 | if (!ret) |
561 | ret = nr; |
562 | break; |
563 | } |
564 | ret += nr; |
565 | if (nr != len) |
566 | break; |
567 | } |
568 | |
569 | return ret; |
570 | } |
571 | |
572 | /* A write operation does a read from user space and vice versa */ |
573 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) |
574 | |
575 | ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, |
576 | unsigned long nr_segs, unsigned long fast_segs, |
577 | struct iovec *fast_pointer, |
578 | struct iovec **ret_pointer) |
579 | { |
580 | unsigned long seg; |
581 | ssize_t ret; |
582 | struct iovec *iov = fast_pointer; |
583 | |
584 | /* |
585 | * SuS says "The readv() function *may* fail if the iovcnt argument |
586 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has |
587 | * traditionally returned zero for zero segments, so... |
588 | */ |
589 | if (nr_segs == 0) { |
590 | ret = 0; |
591 | goto out; |
592 | } |
593 | |
594 | /* |
595 | * First get the "struct iovec" from user memory and |
596 | * verify all the pointers |
597 | */ |
598 | if (nr_segs > UIO_MAXIOV) { |
599 | ret = -EINVAL; |
600 | goto out; |
601 | } |
602 | if (nr_segs > fast_segs) { |
603 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); |
604 | if (iov == NULL) { |
605 | ret = -ENOMEM; |
606 | goto out; |
607 | } |
608 | } |
609 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { |
610 | ret = -EFAULT; |
611 | goto out; |
612 | } |
613 | |
614 | /* |
615 | * According to the Single Unix Specification we should return EINVAL |
616 | * if an element length is < 0 when cast to ssize_t or if the |
617 | * total length would overflow the ssize_t return value of the |
618 | * system call. |
619 | * |
620 | * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the |
621 | * overflow case. |
622 | */ |
623 | ret = 0; |
624 | for (seg = 0; seg < nr_segs; seg++) { |
625 | void __user *buf = iov[seg].iov_base; |
626 | ssize_t len = (ssize_t)iov[seg].iov_len; |
627 | |
628 | /* see if we we're about to use an invalid len or if |
629 | * it's about to overflow ssize_t */ |
630 | if (len < 0) { |
631 | ret = -EINVAL; |
632 | goto out; |
633 | } |
634 | if (unlikely(!access_ok(vrfy_dir(type), buf, len))) { |
635 | ret = -EFAULT; |
636 | goto out; |
637 | } |
638 | if (len > MAX_RW_COUNT - ret) { |
639 | len = MAX_RW_COUNT - ret; |
640 | iov[seg].iov_len = len; |
641 | } |
642 | ret += len; |
643 | } |
644 | out: |
645 | *ret_pointer = iov; |
646 | return ret; |
647 | } |
648 | |
649 | static ssize_t do_readv_writev(int type, struct file *file, |
650 | const struct iovec __user * uvector, |
651 | unsigned long nr_segs, loff_t *pos) |
652 | { |
653 | size_t tot_len; |
654 | struct iovec iovstack[UIO_FASTIOV]; |
655 | struct iovec *iov = iovstack; |
656 | ssize_t ret; |
657 | io_fn_t fn; |
658 | iov_fn_t fnv; |
659 | |
660 | if (!file->f_op) { |
661 | ret = -EINVAL; |
662 | goto out; |
663 | } |
664 | |
665 | ret = rw_copy_check_uvector(type, uvector, nr_segs, |
666 | ARRAY_SIZE(iovstack), iovstack, &iov); |
667 | if (ret <= 0) |
668 | goto out; |
669 | |
670 | tot_len = ret; |
671 | ret = rw_verify_area(type, file, pos, tot_len); |
672 | if (ret < 0) |
673 | goto out; |
674 | |
675 | fnv = NULL; |
676 | if (type == READ) { |
677 | fn = file->f_op->read; |
678 | fnv = file->f_op->aio_read; |
679 | } else { |
680 | fn = (io_fn_t)file->f_op->write; |
681 | fnv = file->f_op->aio_write; |
682 | } |
683 | |
684 | if (fnv) |
685 | ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, |
686 | pos, fnv); |
687 | else |
688 | ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); |
689 | |
690 | out: |
691 | if (iov != iovstack) |
692 | kfree(iov); |
693 | if ((ret + (type == READ)) > 0) { |
694 | if (type == READ) |
695 | fsnotify_access(file); |
696 | else |
697 | fsnotify_modify(file); |
698 | } |
699 | return ret; |
700 | } |
701 | |
702 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, |
703 | unsigned long vlen, loff_t *pos) |
704 | { |
705 | if (!(file->f_mode & FMODE_READ)) |
706 | return -EBADF; |
707 | if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read)) |
708 | return -EINVAL; |
709 | |
710 | return do_readv_writev(READ, file, vec, vlen, pos); |
711 | } |
712 | |
713 | EXPORT_SYMBOL(vfs_readv); |
714 | |
715 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, |
716 | unsigned long vlen, loff_t *pos) |
717 | { |
718 | if (!(file->f_mode & FMODE_WRITE)) |
719 | return -EBADF; |
720 | if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write)) |
721 | return -EINVAL; |
722 | |
723 | return do_readv_writev(WRITE, file, vec, vlen, pos); |
724 | } |
725 | |
726 | EXPORT_SYMBOL(vfs_writev); |
727 | |
728 | SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, |
729 | unsigned long, vlen) |
730 | { |
731 | struct file *file; |
732 | ssize_t ret = -EBADF; |
733 | int fput_needed; |
734 | |
735 | file = fget_light(fd, &fput_needed); |
736 | if (file) { |
737 | loff_t pos = file_pos_read(file); |
738 | ret = vfs_readv(file, vec, vlen, &pos); |
739 | file_pos_write(file, pos); |
740 | fput_light(file, fput_needed); |
741 | } |
742 | |
743 | if (ret > 0) |
744 | add_rchar(current, ret); |
745 | inc_syscr(current); |
746 | return ret; |
747 | } |
748 | |
749 | SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, |
750 | unsigned long, vlen) |
751 | { |
752 | struct file *file; |
753 | ssize_t ret = -EBADF; |
754 | int fput_needed; |
755 | |
756 | file = fget_light(fd, &fput_needed); |
757 | if (file) { |
758 | loff_t pos = file_pos_read(file); |
759 | ret = vfs_writev(file, vec, vlen, &pos); |
760 | file_pos_write(file, pos); |
761 | fput_light(file, fput_needed); |
762 | } |
763 | |
764 | if (ret > 0) |
765 | add_wchar(current, ret); |
766 | inc_syscw(current); |
767 | return ret; |
768 | } |
769 | |
770 | static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) |
771 | { |
772 | #define HALF_LONG_BITS (BITS_PER_LONG / 2) |
773 | return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; |
774 | } |
775 | |
776 | SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, |
777 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
778 | { |
779 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
780 | struct file *file; |
781 | ssize_t ret = -EBADF; |
782 | int fput_needed; |
783 | |
784 | if (pos < 0) |
785 | return -EINVAL; |
786 | |
787 | file = fget_light(fd, &fput_needed); |
788 | if (file) { |
789 | ret = -ESPIPE; |
790 | if (file->f_mode & FMODE_PREAD) |
791 | ret = vfs_readv(file, vec, vlen, &pos); |
792 | fput_light(file, fput_needed); |
793 | } |
794 | |
795 | if (ret > 0) |
796 | add_rchar(current, ret); |
797 | inc_syscr(current); |
798 | return ret; |
799 | } |
800 | |
801 | SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, |
802 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
803 | { |
804 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
805 | struct file *file; |
806 | ssize_t ret = -EBADF; |
807 | int fput_needed; |
808 | |
809 | if (pos < 0) |
810 | return -EINVAL; |
811 | |
812 | file = fget_light(fd, &fput_needed); |
813 | if (file) { |
814 | ret = -ESPIPE; |
815 | if (file->f_mode & FMODE_PWRITE) |
816 | ret = vfs_writev(file, vec, vlen, &pos); |
817 | fput_light(file, fput_needed); |
818 | } |
819 | |
820 | if (ret > 0) |
821 | add_wchar(current, ret); |
822 | inc_syscw(current); |
823 | return ret; |
824 | } |
825 | |
826 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, |
827 | size_t count, loff_t max) |
828 | { |
829 | struct file * in_file, * out_file; |
830 | struct inode * in_inode, * out_inode; |
831 | loff_t pos; |
832 | ssize_t retval; |
833 | int fput_needed_in, fput_needed_out, fl; |
834 | |
835 | /* |
836 | * Get input file, and verify that it is ok.. |
837 | */ |
838 | retval = -EBADF; |
839 | in_file = fget_light(in_fd, &fput_needed_in); |
840 | if (!in_file) |
841 | goto out; |
842 | if (!(in_file->f_mode & FMODE_READ)) |
843 | goto fput_in; |
844 | retval = -ESPIPE; |
845 | if (!ppos) |
846 | ppos = &in_file->f_pos; |
847 | else |
848 | if (!(in_file->f_mode & FMODE_PREAD)) |
849 | goto fput_in; |
850 | retval = rw_verify_area(READ, in_file, ppos, count); |
851 | if (retval < 0) |
852 | goto fput_in; |
853 | count = retval; |
854 | |
855 | /* |
856 | * Get output file, and verify that it is ok.. |
857 | */ |
858 | retval = -EBADF; |
859 | out_file = fget_light(out_fd, &fput_needed_out); |
860 | if (!out_file) |
861 | goto fput_in; |
862 | if (!(out_file->f_mode & FMODE_WRITE)) |
863 | goto fput_out; |
864 | retval = -EINVAL; |
865 | in_inode = in_file->f_path.dentry->d_inode; |
866 | out_inode = out_file->f_path.dentry->d_inode; |
867 | retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); |
868 | if (retval < 0) |
869 | goto fput_out; |
870 | count = retval; |
871 | |
872 | if (!max) |
873 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); |
874 | |
875 | pos = *ppos; |
876 | if (unlikely(pos + count > max)) { |
877 | retval = -EOVERFLOW; |
878 | if (pos >= max) |
879 | goto fput_out; |
880 | count = max - pos; |
881 | } |
882 | |
883 | fl = 0; |
884 | #if 0 |
885 | /* |
886 | * We need to debate whether we can enable this or not. The |
887 | * man page documents EAGAIN return for the output at least, |
888 | * and the application is arguably buggy if it doesn't expect |
889 | * EAGAIN on a non-blocking file descriptor. |
890 | */ |
891 | if (in_file->f_flags & O_NONBLOCK) |
892 | fl = SPLICE_F_NONBLOCK; |
893 | #endif |
894 | retval = do_splice_direct(in_file, ppos, out_file, count, fl); |
895 | |
896 | if (retval > 0) { |
897 | add_rchar(current, retval); |
898 | add_wchar(current, retval); |
899 | } |
900 | |
901 | inc_syscr(current); |
902 | inc_syscw(current); |
903 | if (*ppos > max) |
904 | retval = -EOVERFLOW; |
905 | |
906 | fput_out: |
907 | fput_light(out_file, fput_needed_out); |
908 | fput_in: |
909 | fput_light(in_file, fput_needed_in); |
910 | out: |
911 | return retval; |
912 | } |
913 | |
914 | SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count) |
915 | { |
916 | loff_t pos; |
917 | off_t off; |
918 | ssize_t ret; |
919 | |
920 | if (offset) { |
921 | if (unlikely(get_user(off, offset))) |
922 | return -EFAULT; |
923 | pos = off; |
924 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); |
925 | if (unlikely(put_user(pos, offset))) |
926 | return -EFAULT; |
927 | return ret; |
928 | } |
929 | |
930 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
931 | } |
932 | |
933 | SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count) |
934 | { |
935 | loff_t pos; |
936 | ssize_t ret; |
937 | |
938 | if (offset) { |
939 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) |
940 | return -EFAULT; |
941 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); |
942 | if (unlikely(put_user(pos, offset))) |
943 | return -EFAULT; |
944 | return ret; |
945 | } |
946 | |
947 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
948 | } |
949 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
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jz-3.9-rc8
jz47xx
jz47xx-2.6.38
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Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9