diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/read_write.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/read_write.c')
-rw-r--r-- | fs/read_write.c | 730 |
1 files changed, 730 insertions, 0 deletions
diff --git a/fs/read_write.c b/fs/read_write.c new file mode 100644 index 000000000000..6be4b1a1956b --- /dev/null +++ b/fs/read_write.c | |||
@@ -0,0 +1,730 @@ | |||
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> | ||
13 | #include <linux/dnotify.h> | ||
14 | #include <linux/security.h> | ||
15 | #include <linux/module.h> | ||
16 | #include <linux/syscalls.h> | ||
17 | |||
18 | #include <asm/uaccess.h> | ||
19 | #include <asm/unistd.h> | ||
20 | |||
21 | struct file_operations generic_ro_fops = { | ||
22 | .llseek = generic_file_llseek, | ||
23 | .read = generic_file_read, | ||
24 | .mmap = generic_file_readonly_mmap, | ||
25 | .sendfile = generic_file_sendfile, | ||
26 | }; | ||
27 | |||
28 | EXPORT_SYMBOL(generic_ro_fops); | ||
29 | |||
30 | loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) | ||
31 | { | ||
32 | long long retval; | ||
33 | struct inode *inode = file->f_mapping->host; | ||
34 | |||
35 | down(&inode->i_sem); | ||
36 | switch (origin) { | ||
37 | case 2: | ||
38 | offset += inode->i_size; | ||
39 | break; | ||
40 | case 1: | ||
41 | offset += file->f_pos; | ||
42 | } | ||
43 | retval = -EINVAL; | ||
44 | if (offset>=0 && offset<=inode->i_sb->s_maxbytes) { | ||
45 | if (offset != file->f_pos) { | ||
46 | file->f_pos = offset; | ||
47 | file->f_version = 0; | ||
48 | } | ||
49 | retval = offset; | ||
50 | } | ||
51 | up(&inode->i_sem); | ||
52 | return retval; | ||
53 | } | ||
54 | |||
55 | EXPORT_SYMBOL(generic_file_llseek); | ||
56 | |||
57 | loff_t remote_llseek(struct file *file, loff_t offset, int origin) | ||
58 | { | ||
59 | long long retval; | ||
60 | |||
61 | lock_kernel(); | ||
62 | switch (origin) { | ||
63 | case 2: | ||
64 | offset += i_size_read(file->f_dentry->d_inode); | ||
65 | break; | ||
66 | case 1: | ||
67 | offset += file->f_pos; | ||
68 | } | ||
69 | retval = -EINVAL; | ||
70 | if (offset>=0 && offset<=file->f_dentry->d_inode->i_sb->s_maxbytes) { | ||
71 | if (offset != file->f_pos) { | ||
72 | file->f_pos = offset; | ||
73 | file->f_version = 0; | ||
74 | } | ||
75 | retval = offset; | ||
76 | } | ||
77 | unlock_kernel(); | ||
78 | return retval; | ||
79 | } | ||
80 | EXPORT_SYMBOL(remote_llseek); | ||
81 | |||
82 | loff_t no_llseek(struct file *file, loff_t offset, int origin) | ||
83 | { | ||
84 | return -ESPIPE; | ||
85 | } | ||
86 | EXPORT_SYMBOL(no_llseek); | ||
87 | |||
88 | loff_t default_llseek(struct file *file, loff_t offset, int origin) | ||
89 | { | ||
90 | long long retval; | ||
91 | |||
92 | lock_kernel(); | ||
93 | switch (origin) { | ||
94 | case 2: | ||
95 | offset += i_size_read(file->f_dentry->d_inode); | ||
96 | break; | ||
97 | case 1: | ||
98 | offset += file->f_pos; | ||
99 | } | ||
100 | retval = -EINVAL; | ||
101 | if (offset >= 0) { | ||
102 | if (offset != file->f_pos) { | ||
103 | file->f_pos = offset; | ||
104 | file->f_version = 0; | ||
105 | } | ||
106 | retval = offset; | ||
107 | } | ||
108 | unlock_kernel(); | ||
109 | return retval; | ||
110 | } | ||
111 | EXPORT_SYMBOL(default_llseek); | ||
112 | |||
113 | loff_t vfs_llseek(struct file *file, loff_t offset, int origin) | ||
114 | { | ||
115 | loff_t (*fn)(struct file *, loff_t, int); | ||
116 | |||
117 | fn = no_llseek; | ||
118 | if (file->f_mode & FMODE_LSEEK) { | ||
119 | fn = default_llseek; | ||
120 | if (file->f_op && file->f_op->llseek) | ||
121 | fn = file->f_op->llseek; | ||
122 | } | ||
123 | return fn(file, offset, origin); | ||
124 | } | ||
125 | EXPORT_SYMBOL(vfs_llseek); | ||
126 | |||
127 | asmlinkage off_t sys_lseek(unsigned int fd, off_t offset, unsigned int origin) | ||
128 | { | ||
129 | off_t retval; | ||
130 | struct file * file; | ||
131 | int fput_needed; | ||
132 | |||
133 | retval = -EBADF; | ||
134 | file = fget_light(fd, &fput_needed); | ||
135 | if (!file) | ||
136 | goto bad; | ||
137 | |||
138 | retval = -EINVAL; | ||
139 | if (origin <= 2) { | ||
140 | loff_t res = vfs_llseek(file, offset, origin); | ||
141 | retval = res; | ||
142 | if (res != (loff_t)retval) | ||
143 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ | ||
144 | } | ||
145 | fput_light(file, fput_needed); | ||
146 | bad: | ||
147 | return retval; | ||
148 | } | ||
149 | |||
150 | #ifdef __ARCH_WANT_SYS_LLSEEK | ||
151 | asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high, | ||
152 | unsigned long offset_low, loff_t __user * result, | ||
153 | unsigned int origin) | ||
154 | { | ||
155 | int retval; | ||
156 | struct file * file; | ||
157 | loff_t offset; | ||
158 | int fput_needed; | ||
159 | |||
160 | retval = -EBADF; | ||
161 | file = fget_light(fd, &fput_needed); | ||
162 | if (!file) | ||
163 | goto bad; | ||
164 | |||
165 | retval = -EINVAL; | ||
166 | if (origin > 2) | ||
167 | goto out_putf; | ||
168 | |||
169 | offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low, | ||
170 | origin); | ||
171 | |||
172 | retval = (int)offset; | ||
173 | if (offset >= 0) { | ||
174 | retval = -EFAULT; | ||
175 | if (!copy_to_user(result, &offset, sizeof(offset))) | ||
176 | retval = 0; | ||
177 | } | ||
178 | out_putf: | ||
179 | fput_light(file, fput_needed); | ||
180 | bad: | ||
181 | return retval; | ||
182 | } | ||
183 | #endif | ||
184 | |||
185 | |||
186 | int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count) | ||
187 | { | ||
188 | struct inode *inode; | ||
189 | loff_t pos; | ||
190 | |||
191 | if (unlikely(count > file->f_maxcount)) | ||
192 | goto Einval; | ||
193 | pos = *ppos; | ||
194 | if (unlikely((pos < 0) || (loff_t) (pos + count) < 0)) | ||
195 | goto Einval; | ||
196 | |||
197 | inode = file->f_dentry->d_inode; | ||
198 | if (inode->i_flock && MANDATORY_LOCK(inode)) | ||
199 | return locks_mandatory_area(read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, inode, file, pos, count); | ||
200 | return 0; | ||
201 | |||
202 | Einval: | ||
203 | return -EINVAL; | ||
204 | } | ||
205 | |||
206 | ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) | ||
207 | { | ||
208 | struct kiocb kiocb; | ||
209 | ssize_t ret; | ||
210 | |||
211 | init_sync_kiocb(&kiocb, filp); | ||
212 | kiocb.ki_pos = *ppos; | ||
213 | ret = filp->f_op->aio_read(&kiocb, buf, len, kiocb.ki_pos); | ||
214 | if (-EIOCBQUEUED == ret) | ||
215 | ret = wait_on_sync_kiocb(&kiocb); | ||
216 | *ppos = kiocb.ki_pos; | ||
217 | return ret; | ||
218 | } | ||
219 | |||
220 | EXPORT_SYMBOL(do_sync_read); | ||
221 | |||
222 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) | ||
223 | { | ||
224 | ssize_t ret; | ||
225 | |||
226 | if (!(file->f_mode & FMODE_READ)) | ||
227 | return -EBADF; | ||
228 | if (!file->f_op || (!file->f_op->read && !file->f_op->aio_read)) | ||
229 | return -EINVAL; | ||
230 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) | ||
231 | return -EFAULT; | ||
232 | |||
233 | ret = rw_verify_area(READ, file, pos, count); | ||
234 | if (!ret) { | ||
235 | ret = security_file_permission (file, MAY_READ); | ||
236 | if (!ret) { | ||
237 | if (file->f_op->read) | ||
238 | ret = file->f_op->read(file, buf, count, pos); | ||
239 | else | ||
240 | ret = do_sync_read(file, buf, count, pos); | ||
241 | if (ret > 0) { | ||
242 | dnotify_parent(file->f_dentry, DN_ACCESS); | ||
243 | current->rchar += ret; | ||
244 | } | ||
245 | current->syscr++; | ||
246 | } | ||
247 | } | ||
248 | |||
249 | return ret; | ||
250 | } | ||
251 | |||
252 | EXPORT_SYMBOL(vfs_read); | ||
253 | |||
254 | ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) | ||
255 | { | ||
256 | struct kiocb kiocb; | ||
257 | ssize_t ret; | ||
258 | |||
259 | init_sync_kiocb(&kiocb, filp); | ||
260 | kiocb.ki_pos = *ppos; | ||
261 | ret = filp->f_op->aio_write(&kiocb, buf, len, kiocb.ki_pos); | ||
262 | if (-EIOCBQUEUED == ret) | ||
263 | ret = wait_on_sync_kiocb(&kiocb); | ||
264 | *ppos = kiocb.ki_pos; | ||
265 | return ret; | ||
266 | } | ||
267 | |||
268 | EXPORT_SYMBOL(do_sync_write); | ||
269 | |||
270 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) | ||
271 | { | ||
272 | ssize_t ret; | ||
273 | |||
274 | if (!(file->f_mode & FMODE_WRITE)) | ||
275 | return -EBADF; | ||
276 | if (!file->f_op || (!file->f_op->write && !file->f_op->aio_write)) | ||
277 | return -EINVAL; | ||
278 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) | ||
279 | return -EFAULT; | ||
280 | |||
281 | ret = rw_verify_area(WRITE, file, pos, count); | ||
282 | if (!ret) { | ||
283 | ret = security_file_permission (file, MAY_WRITE); | ||
284 | if (!ret) { | ||
285 | if (file->f_op->write) | ||
286 | ret = file->f_op->write(file, buf, count, pos); | ||
287 | else | ||
288 | ret = do_sync_write(file, buf, count, pos); | ||
289 | if (ret > 0) { | ||
290 | dnotify_parent(file->f_dentry, DN_MODIFY); | ||
291 | current->wchar += ret; | ||
292 | } | ||
293 | current->syscw++; | ||
294 | } | ||
295 | } | ||
296 | |||
297 | return ret; | ||
298 | } | ||
299 | |||
300 | EXPORT_SYMBOL(vfs_write); | ||
301 | |||
302 | static inline loff_t file_pos_read(struct file *file) | ||
303 | { | ||
304 | return file->f_pos; | ||
305 | } | ||
306 | |||
307 | static inline void file_pos_write(struct file *file, loff_t pos) | ||
308 | { | ||
309 | file->f_pos = pos; | ||
310 | } | ||
311 | |||
312 | asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count) | ||
313 | { | ||
314 | struct file *file; | ||
315 | ssize_t ret = -EBADF; | ||
316 | int fput_needed; | ||
317 | |||
318 | file = fget_light(fd, &fput_needed); | ||
319 | if (file) { | ||
320 | loff_t pos = file_pos_read(file); | ||
321 | ret = vfs_read(file, buf, count, &pos); | ||
322 | file_pos_write(file, pos); | ||
323 | fput_light(file, fput_needed); | ||
324 | } | ||
325 | |||
326 | return ret; | ||
327 | } | ||
328 | EXPORT_SYMBOL_GPL(sys_read); | ||
329 | |||
330 | asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t count) | ||
331 | { | ||
332 | struct file *file; | ||
333 | ssize_t ret = -EBADF; | ||
334 | int fput_needed; | ||
335 | |||
336 | file = fget_light(fd, &fput_needed); | ||
337 | if (file) { | ||
338 | loff_t pos = file_pos_read(file); | ||
339 | ret = vfs_write(file, buf, count, &pos); | ||
340 | file_pos_write(file, pos); | ||
341 | fput_light(file, fput_needed); | ||
342 | } | ||
343 | |||
344 | return ret; | ||
345 | } | ||
346 | |||
347 | asmlinkage ssize_t sys_pread64(unsigned int fd, char __user *buf, | ||
348 | size_t count, loff_t pos) | ||
349 | { | ||
350 | struct file *file; | ||
351 | ssize_t ret = -EBADF; | ||
352 | int fput_needed; | ||
353 | |||
354 | if (pos < 0) | ||
355 | return -EINVAL; | ||
356 | |||
357 | file = fget_light(fd, &fput_needed); | ||
358 | if (file) { | ||
359 | ret = -ESPIPE; | ||
360 | if (file->f_mode & FMODE_PREAD) | ||
361 | ret = vfs_read(file, buf, count, &pos); | ||
362 | fput_light(file, fput_needed); | ||
363 | } | ||
364 | |||
365 | return ret; | ||
366 | } | ||
367 | |||
368 | asmlinkage ssize_t sys_pwrite64(unsigned int fd, const char __user *buf, | ||
369 | size_t count, loff_t pos) | ||
370 | { | ||
371 | struct file *file; | ||
372 | ssize_t ret = -EBADF; | ||
373 | int fput_needed; | ||
374 | |||
375 | if (pos < 0) | ||
376 | return -EINVAL; | ||
377 | |||
378 | file = fget_light(fd, &fput_needed); | ||
379 | if (file) { | ||
380 | ret = -ESPIPE; | ||
381 | if (file->f_mode & FMODE_PWRITE) | ||
382 | ret = vfs_write(file, buf, count, &pos); | ||
383 | fput_light(file, fput_needed); | ||
384 | } | ||
385 | |||
386 | return ret; | ||
387 | } | ||
388 | |||
389 | /* | ||
390 | * Reduce an iovec's length in-place. Return the resulting number of segments | ||
391 | */ | ||
392 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) | ||
393 | { | ||
394 | unsigned long seg = 0; | ||
395 | size_t len = 0; | ||
396 | |||
397 | while (seg < nr_segs) { | ||
398 | seg++; | ||
399 | if (len + iov->iov_len >= to) { | ||
400 | iov->iov_len = to - len; | ||
401 | break; | ||
402 | } | ||
403 | len += iov->iov_len; | ||
404 | iov++; | ||
405 | } | ||
406 | return seg; | ||
407 | } | ||
408 | |||
409 | EXPORT_SYMBOL(iov_shorten); | ||
410 | |||
411 | /* A write operation does a read from user space and vice versa */ | ||
412 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) | ||
413 | |||
414 | static ssize_t do_readv_writev(int type, struct file *file, | ||
415 | const struct iovec __user * uvector, | ||
416 | unsigned long nr_segs, loff_t *pos) | ||
417 | { | ||
418 | typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *); | ||
419 | typedef ssize_t (*iov_fn_t)(struct file *, const struct iovec *, unsigned long, loff_t *); | ||
420 | |||
421 | size_t tot_len; | ||
422 | struct iovec iovstack[UIO_FASTIOV]; | ||
423 | struct iovec *iov=iovstack, *vector; | ||
424 | ssize_t ret; | ||
425 | int seg; | ||
426 | io_fn_t fn; | ||
427 | iov_fn_t fnv; | ||
428 | |||
429 | /* | ||
430 | * SuS says "The readv() function *may* fail if the iovcnt argument | ||
431 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has | ||
432 | * traditionally returned zero for zero segments, so... | ||
433 | */ | ||
434 | ret = 0; | ||
435 | if (nr_segs == 0) | ||
436 | goto out; | ||
437 | |||
438 | /* | ||
439 | * First get the "struct iovec" from user memory and | ||
440 | * verify all the pointers | ||
441 | */ | ||
442 | ret = -EINVAL; | ||
443 | if ((nr_segs > UIO_MAXIOV) || (nr_segs <= 0)) | ||
444 | goto out; | ||
445 | if (!file->f_op) | ||
446 | goto out; | ||
447 | if (nr_segs > UIO_FASTIOV) { | ||
448 | ret = -ENOMEM; | ||
449 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); | ||
450 | if (!iov) | ||
451 | goto out; | ||
452 | } | ||
453 | ret = -EFAULT; | ||
454 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) | ||
455 | goto out; | ||
456 | |||
457 | /* | ||
458 | * Single unix specification: | ||
459 | * We should -EINVAL if an element length is not >= 0 and fitting an | ||
460 | * ssize_t. The total length is fitting an ssize_t | ||
461 | * | ||
462 | * Be careful here because iov_len is a size_t not an ssize_t | ||
463 | */ | ||
464 | tot_len = 0; | ||
465 | ret = -EINVAL; | ||
466 | for (seg = 0; seg < nr_segs; seg++) { | ||
467 | void __user *buf = iov[seg].iov_base; | ||
468 | ssize_t len = (ssize_t)iov[seg].iov_len; | ||
469 | |||
470 | if (unlikely(!access_ok(vrfy_dir(type), buf, len))) | ||
471 | goto Efault; | ||
472 | if (len < 0) /* size_t not fitting an ssize_t .. */ | ||
473 | goto out; | ||
474 | tot_len += len; | ||
475 | if ((ssize_t)tot_len < 0) /* maths overflow on the ssize_t */ | ||
476 | goto out; | ||
477 | } | ||
478 | if (tot_len == 0) { | ||
479 | ret = 0; | ||
480 | goto out; | ||
481 | } | ||
482 | |||
483 | ret = rw_verify_area(type, file, pos, tot_len); | ||
484 | if (ret) | ||
485 | goto out; | ||
486 | |||
487 | fnv = NULL; | ||
488 | if (type == READ) { | ||
489 | fn = file->f_op->read; | ||
490 | fnv = file->f_op->readv; | ||
491 | } else { | ||
492 | fn = (io_fn_t)file->f_op->write; | ||
493 | fnv = file->f_op->writev; | ||
494 | } | ||
495 | if (fnv) { | ||
496 | ret = fnv(file, iov, nr_segs, pos); | ||
497 | goto out; | ||
498 | } | ||
499 | |||
500 | /* Do it by hand, with file-ops */ | ||
501 | ret = 0; | ||
502 | vector = iov; | ||
503 | while (nr_segs > 0) { | ||
504 | void __user * base; | ||
505 | size_t len; | ||
506 | ssize_t nr; | ||
507 | |||
508 | base = vector->iov_base; | ||
509 | len = vector->iov_len; | ||
510 | vector++; | ||
511 | nr_segs--; | ||
512 | |||
513 | nr = fn(file, base, len, pos); | ||
514 | |||
515 | if (nr < 0) { | ||
516 | if (!ret) ret = nr; | ||
517 | break; | ||
518 | } | ||
519 | ret += nr; | ||
520 | if (nr != len) | ||
521 | break; | ||
522 | } | ||
523 | out: | ||
524 | if (iov != iovstack) | ||
525 | kfree(iov); | ||
526 | if ((ret + (type == READ)) > 0) | ||
527 | dnotify_parent(file->f_dentry, | ||
528 | (type == READ) ? DN_ACCESS : DN_MODIFY); | ||
529 | return ret; | ||
530 | Efault: | ||
531 | ret = -EFAULT; | ||
532 | goto out; | ||
533 | } | ||
534 | |||
535 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, | ||
536 | unsigned long vlen, loff_t *pos) | ||
537 | { | ||
538 | if (!(file->f_mode & FMODE_READ)) | ||
539 | return -EBADF; | ||
540 | if (!file->f_op || (!file->f_op->readv && !file->f_op->read)) | ||
541 | return -EINVAL; | ||
542 | |||
543 | return do_readv_writev(READ, file, vec, vlen, pos); | ||
544 | } | ||
545 | |||
546 | EXPORT_SYMBOL(vfs_readv); | ||
547 | |||
548 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, | ||
549 | unsigned long vlen, loff_t *pos) | ||
550 | { | ||
551 | if (!(file->f_mode & FMODE_WRITE)) | ||
552 | return -EBADF; | ||
553 | if (!file->f_op || (!file->f_op->writev && !file->f_op->write)) | ||
554 | return -EINVAL; | ||
555 | |||
556 | return do_readv_writev(WRITE, file, vec, vlen, pos); | ||
557 | } | ||
558 | |||
559 | EXPORT_SYMBOL(vfs_writev); | ||
560 | |||
561 | asmlinkage ssize_t | ||
562 | sys_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) | ||
563 | { | ||
564 | struct file *file; | ||
565 | ssize_t ret = -EBADF; | ||
566 | int fput_needed; | ||
567 | |||
568 | file = fget_light(fd, &fput_needed); | ||
569 | if (file) { | ||
570 | loff_t pos = file_pos_read(file); | ||
571 | ret = vfs_readv(file, vec, vlen, &pos); | ||
572 | file_pos_write(file, pos); | ||
573 | fput_light(file, fput_needed); | ||
574 | } | ||
575 | |||
576 | if (ret > 0) | ||
577 | current->rchar += ret; | ||
578 | current->syscr++; | ||
579 | return ret; | ||
580 | } | ||
581 | |||
582 | asmlinkage ssize_t | ||
583 | sys_writev(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) | ||
584 | { | ||
585 | struct file *file; | ||
586 | ssize_t ret = -EBADF; | ||
587 | int fput_needed; | ||
588 | |||
589 | file = fget_light(fd, &fput_needed); | ||
590 | if (file) { | ||
591 | loff_t pos = file_pos_read(file); | ||
592 | ret = vfs_writev(file, vec, vlen, &pos); | ||
593 | file_pos_write(file, pos); | ||
594 | fput_light(file, fput_needed); | ||
595 | } | ||
596 | |||
597 | if (ret > 0) | ||
598 | current->wchar += ret; | ||
599 | current->syscw++; | ||
600 | return ret; | ||
601 | } | ||
602 | |||
603 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, | ||
604 | size_t count, loff_t max) | ||
605 | { | ||
606 | struct file * in_file, * out_file; | ||
607 | struct inode * in_inode, * out_inode; | ||
608 | loff_t pos; | ||
609 | ssize_t retval; | ||
610 | int fput_needed_in, fput_needed_out; | ||
611 | |||
612 | /* | ||
613 | * Get input file, and verify that it is ok.. | ||
614 | */ | ||
615 | retval = -EBADF; | ||
616 | in_file = fget_light(in_fd, &fput_needed_in); | ||
617 | if (!in_file) | ||
618 | goto out; | ||
619 | if (!(in_file->f_mode & FMODE_READ)) | ||
620 | goto fput_in; | ||
621 | retval = -EINVAL; | ||
622 | in_inode = in_file->f_dentry->d_inode; | ||
623 | if (!in_inode) | ||
624 | goto fput_in; | ||
625 | if (!in_file->f_op || !in_file->f_op->sendfile) | ||
626 | goto fput_in; | ||
627 | retval = -ESPIPE; | ||
628 | if (!ppos) | ||
629 | ppos = &in_file->f_pos; | ||
630 | else | ||
631 | if (!(in_file->f_mode & FMODE_PREAD)) | ||
632 | goto fput_in; | ||
633 | retval = rw_verify_area(READ, in_file, ppos, count); | ||
634 | if (retval) | ||
635 | goto fput_in; | ||
636 | |||
637 | retval = security_file_permission (in_file, MAY_READ); | ||
638 | if (retval) | ||
639 | goto fput_in; | ||
640 | |||
641 | /* | ||
642 | * Get output file, and verify that it is ok.. | ||
643 | */ | ||
644 | retval = -EBADF; | ||
645 | out_file = fget_light(out_fd, &fput_needed_out); | ||
646 | if (!out_file) | ||
647 | goto fput_in; | ||
648 | if (!(out_file->f_mode & FMODE_WRITE)) | ||
649 | goto fput_out; | ||
650 | retval = -EINVAL; | ||
651 | if (!out_file->f_op || !out_file->f_op->sendpage) | ||
652 | goto fput_out; | ||
653 | out_inode = out_file->f_dentry->d_inode; | ||
654 | retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); | ||
655 | if (retval) | ||
656 | goto fput_out; | ||
657 | |||
658 | retval = security_file_permission (out_file, MAY_WRITE); | ||
659 | if (retval) | ||
660 | goto fput_out; | ||
661 | |||
662 | if (!max) | ||
663 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); | ||
664 | |||
665 | pos = *ppos; | ||
666 | retval = -EINVAL; | ||
667 | if (unlikely(pos < 0)) | ||
668 | goto fput_out; | ||
669 | if (unlikely(pos + count > max)) { | ||
670 | retval = -EOVERFLOW; | ||
671 | if (pos >= max) | ||
672 | goto fput_out; | ||
673 | count = max - pos; | ||
674 | } | ||
675 | |||
676 | retval = in_file->f_op->sendfile(in_file, ppos, count, file_send_actor, out_file); | ||
677 | |||
678 | if (retval > 0) { | ||
679 | current->rchar += retval; | ||
680 | current->wchar += retval; | ||
681 | } | ||
682 | current->syscr++; | ||
683 | current->syscw++; | ||
684 | |||
685 | if (*ppos > max) | ||
686 | retval = -EOVERFLOW; | ||
687 | |||
688 | fput_out: | ||
689 | fput_light(out_file, fput_needed_out); | ||
690 | fput_in: | ||
691 | fput_light(in_file, fput_needed_in); | ||
692 | out: | ||
693 | return retval; | ||
694 | } | ||
695 | |||
696 | asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t __user *offset, size_t count) | ||
697 | { | ||
698 | loff_t pos; | ||
699 | off_t off; | ||
700 | ssize_t ret; | ||
701 | |||
702 | if (offset) { | ||
703 | if (unlikely(get_user(off, offset))) | ||
704 | return -EFAULT; | ||
705 | pos = off; | ||
706 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | ||
707 | if (unlikely(put_user(pos, offset))) | ||
708 | return -EFAULT; | ||
709 | return ret; | ||
710 | } | ||
711 | |||
712 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | ||
713 | } | ||
714 | |||
715 | asmlinkage ssize_t sys_sendfile64(int out_fd, int in_fd, loff_t __user *offset, size_t count) | ||
716 | { | ||
717 | loff_t pos; | ||
718 | ssize_t ret; | ||
719 | |||
720 | if (offset) { | ||
721 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | ||
722 | return -EFAULT; | ||
723 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | ||
724 | if (unlikely(put_user(pos, offset))) | ||
725 | return -EFAULT; | ||
726 | return ret; | ||
727 | } | ||
728 | |||
729 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | ||
730 | } | ||