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> | |
a27bb332 | 12 | #include <linux/aio.h> |
0eeca283 | 13 | #include <linux/fsnotify.h> |
1da177e4 | 14 | #include <linux/security.h> |
630d9c47 | 15 | #include <linux/export.h> |
1da177e4 | 16 | #include <linux/syscalls.h> |
e28cc715 | 17 | #include <linux/pagemap.h> |
d6b29d7c | 18 | #include <linux/splice.h> |
561c6731 | 19 | #include <linux/compat.h> |
06ae43f3 | 20 | #include "internal.h" |
1da177e4 LT |
21 | |
22 | #include <asm/uaccess.h> | |
23 | #include <asm/unistd.h> | |
24 | ||
c0bd14af AV |
25 | typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *); |
26 | typedef ssize_t (*iov_fn_t)(struct kiocb *, const struct iovec *, | |
27 | unsigned long, loff_t); | |
293bc982 | 28 | typedef ssize_t (*iter_fn_t)(struct kiocb *, struct iov_iter *); |
c0bd14af | 29 | |
4b6f5d20 | 30 | const struct file_operations generic_ro_fops = { |
1da177e4 | 31 | .llseek = generic_file_llseek, |
aad4f8bb AV |
32 | .read = new_sync_read, |
33 | .read_iter = generic_file_read_iter, | |
1da177e4 | 34 | .mmap = generic_file_readonly_mmap, |
534f2aaa | 35 | .splice_read = generic_file_splice_read, |
1da177e4 LT |
36 | }; |
37 | ||
38 | EXPORT_SYMBOL(generic_ro_fops); | |
39 | ||
cccb5a1e | 40 | static inline int unsigned_offsets(struct file *file) |
4a3956c7 | 41 | { |
cccb5a1e | 42 | return file->f_mode & FMODE_UNSIGNED_OFFSET; |
4a3956c7 KH |
43 | } |
44 | ||
46a1c2c7 JL |
45 | /** |
46 | * vfs_setpos - update the file offset for lseek | |
47 | * @file: file structure in question | |
48 | * @offset: file offset to seek to | |
49 | * @maxsize: maximum file size | |
50 | * | |
51 | * This is a low-level filesystem helper for updating the file offset to | |
52 | * the value specified by @offset if the given offset is valid and it is | |
53 | * not equal to the current file offset. | |
54 | * | |
55 | * Return the specified offset on success and -EINVAL on invalid offset. | |
56 | */ | |
57 | loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize) | |
ef3d0fd2 AK |
58 | { |
59 | if (offset < 0 && !unsigned_offsets(file)) | |
60 | return -EINVAL; | |
61 | if (offset > maxsize) | |
62 | return -EINVAL; | |
63 | ||
64 | if (offset != file->f_pos) { | |
65 | file->f_pos = offset; | |
66 | file->f_version = 0; | |
67 | } | |
68 | return offset; | |
69 | } | |
46a1c2c7 | 70 | EXPORT_SYMBOL(vfs_setpos); |
ef3d0fd2 | 71 | |
3a8cff4f | 72 | /** |
5760495a | 73 | * generic_file_llseek_size - generic llseek implementation for regular files |
3a8cff4f CH |
74 | * @file: file structure to seek on |
75 | * @offset: file offset to seek to | |
965c8e59 | 76 | * @whence: type of seek |
e8b96eb5 ES |
77 | * @size: max size of this file in file system |
78 | * @eof: offset used for SEEK_END position | |
3a8cff4f | 79 | * |
5760495a | 80 | * This is a variant of generic_file_llseek that allows passing in a custom |
e8b96eb5 | 81 | * maximum file size and a custom EOF position, for e.g. hashed directories |
ef3d0fd2 AK |
82 | * |
83 | * Synchronization: | |
5760495a | 84 | * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms) |
ef3d0fd2 AK |
85 | * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes. |
86 | * read/writes behave like SEEK_SET against seeks. | |
3a8cff4f | 87 | */ |
9465efc9 | 88 | loff_t |
965c8e59 | 89 | generic_file_llseek_size(struct file *file, loff_t offset, int whence, |
e8b96eb5 | 90 | loff_t maxsize, loff_t eof) |
1da177e4 | 91 | { |
965c8e59 | 92 | switch (whence) { |
3a8cff4f | 93 | case SEEK_END: |
e8b96eb5 | 94 | offset += eof; |
3a8cff4f CH |
95 | break; |
96 | case SEEK_CUR: | |
5b6f1eb9 AK |
97 | /* |
98 | * Here we special-case the lseek(fd, 0, SEEK_CUR) | |
99 | * position-querying operation. Avoid rewriting the "same" | |
100 | * f_pos value back to the file because a concurrent read(), | |
101 | * write() or lseek() might have altered it | |
102 | */ | |
103 | if (offset == 0) | |
104 | return file->f_pos; | |
ef3d0fd2 AK |
105 | /* |
106 | * f_lock protects against read/modify/write race with other | |
107 | * SEEK_CURs. Note that parallel writes and reads behave | |
108 | * like SEEK_SET. | |
109 | */ | |
110 | spin_lock(&file->f_lock); | |
46a1c2c7 | 111 | offset = vfs_setpos(file, file->f_pos + offset, maxsize); |
ef3d0fd2 AK |
112 | spin_unlock(&file->f_lock); |
113 | return offset; | |
982d8165 JB |
114 | case SEEK_DATA: |
115 | /* | |
116 | * In the generic case the entire file is data, so as long as | |
117 | * offset isn't at the end of the file then the offset is data. | |
118 | */ | |
e8b96eb5 | 119 | if (offset >= eof) |
982d8165 JB |
120 | return -ENXIO; |
121 | break; | |
122 | case SEEK_HOLE: | |
123 | /* | |
124 | * There is a virtual hole at the end of the file, so as long as | |
125 | * offset isn't i_size or larger, return i_size. | |
126 | */ | |
e8b96eb5 | 127 | if (offset >= eof) |
982d8165 | 128 | return -ENXIO; |
e8b96eb5 | 129 | offset = eof; |
982d8165 | 130 | break; |
1da177e4 | 131 | } |
3a8cff4f | 132 | |
46a1c2c7 | 133 | return vfs_setpos(file, offset, maxsize); |
5760495a AK |
134 | } |
135 | EXPORT_SYMBOL(generic_file_llseek_size); | |
136 | ||
137 | /** | |
138 | * generic_file_llseek - generic llseek implementation for regular files | |
139 | * @file: file structure to seek on | |
140 | * @offset: file offset to seek to | |
965c8e59 | 141 | * @whence: type of seek |
5760495a AK |
142 | * |
143 | * This is a generic implemenation of ->llseek useable for all normal local | |
144 | * filesystems. It just updates the file offset to the value specified by | |
546ae2d2 | 145 | * @offset and @whence. |
5760495a | 146 | */ |
965c8e59 | 147 | loff_t generic_file_llseek(struct file *file, loff_t offset, int whence) |
5760495a AK |
148 | { |
149 | struct inode *inode = file->f_mapping->host; | |
150 | ||
965c8e59 | 151 | return generic_file_llseek_size(file, offset, whence, |
e8b96eb5 ES |
152 | inode->i_sb->s_maxbytes, |
153 | i_size_read(inode)); | |
1da177e4 | 154 | } |
9465efc9 | 155 | EXPORT_SYMBOL(generic_file_llseek); |
1da177e4 | 156 | |
1bf9d14d AV |
157 | /** |
158 | * fixed_size_llseek - llseek implementation for fixed-sized devices | |
159 | * @file: file structure to seek on | |
160 | * @offset: file offset to seek to | |
161 | * @whence: type of seek | |
162 | * @size: size of the file | |
163 | * | |
164 | */ | |
165 | loff_t fixed_size_llseek(struct file *file, loff_t offset, int whence, loff_t size) | |
166 | { | |
167 | switch (whence) { | |
168 | case SEEK_SET: case SEEK_CUR: case SEEK_END: | |
169 | return generic_file_llseek_size(file, offset, whence, | |
170 | size, size); | |
171 | default: | |
172 | return -EINVAL; | |
173 | } | |
174 | } | |
175 | EXPORT_SYMBOL(fixed_size_llseek); | |
176 | ||
ae6afc3f B |
177 | /** |
178 | * noop_llseek - No Operation Performed llseek implementation | |
179 | * @file: file structure to seek on | |
180 | * @offset: file offset to seek to | |
965c8e59 | 181 | * @whence: type of seek |
ae6afc3f B |
182 | * |
183 | * This is an implementation of ->llseek useable for the rare special case when | |
184 | * userspace expects the seek to succeed but the (device) file is actually not | |
185 | * able to perform the seek. In this case you use noop_llseek() instead of | |
186 | * falling back to the default implementation of ->llseek. | |
187 | */ | |
965c8e59 | 188 | loff_t noop_llseek(struct file *file, loff_t offset, int whence) |
ae6afc3f B |
189 | { |
190 | return file->f_pos; | |
191 | } | |
192 | EXPORT_SYMBOL(noop_llseek); | |
193 | ||
965c8e59 | 194 | loff_t no_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 LT |
195 | { |
196 | return -ESPIPE; | |
197 | } | |
198 | EXPORT_SYMBOL(no_llseek); | |
199 | ||
965c8e59 | 200 | loff_t default_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 | 201 | { |
496ad9aa | 202 | struct inode *inode = file_inode(file); |
16abef0e | 203 | loff_t retval; |
1da177e4 | 204 | |
982d8165 | 205 | mutex_lock(&inode->i_mutex); |
965c8e59 | 206 | switch (whence) { |
7b8e8924 | 207 | case SEEK_END: |
982d8165 | 208 | offset += i_size_read(inode); |
1da177e4 | 209 | break; |
7b8e8924 | 210 | case SEEK_CUR: |
5b6f1eb9 AK |
211 | if (offset == 0) { |
212 | retval = file->f_pos; | |
213 | goto out; | |
214 | } | |
1da177e4 | 215 | offset += file->f_pos; |
982d8165 JB |
216 | break; |
217 | case SEEK_DATA: | |
218 | /* | |
219 | * In the generic case the entire file is data, so as | |
220 | * long as offset isn't at the end of the file then the | |
221 | * offset is data. | |
222 | */ | |
bacb2d81 DC |
223 | if (offset >= inode->i_size) { |
224 | retval = -ENXIO; | |
225 | goto out; | |
226 | } | |
982d8165 JB |
227 | break; |
228 | case SEEK_HOLE: | |
229 | /* | |
230 | * There is a virtual hole at the end of the file, so | |
231 | * as long as offset isn't i_size or larger, return | |
232 | * i_size. | |
233 | */ | |
bacb2d81 DC |
234 | if (offset >= inode->i_size) { |
235 | retval = -ENXIO; | |
236 | goto out; | |
237 | } | |
982d8165 JB |
238 | offset = inode->i_size; |
239 | break; | |
1da177e4 LT |
240 | } |
241 | retval = -EINVAL; | |
cccb5a1e | 242 | if (offset >= 0 || unsigned_offsets(file)) { |
1da177e4 LT |
243 | if (offset != file->f_pos) { |
244 | file->f_pos = offset; | |
245 | file->f_version = 0; | |
246 | } | |
247 | retval = offset; | |
248 | } | |
5b6f1eb9 | 249 | out: |
982d8165 | 250 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
251 | return retval; |
252 | } | |
253 | EXPORT_SYMBOL(default_llseek); | |
254 | ||
965c8e59 | 255 | loff_t vfs_llseek(struct file *file, loff_t offset, int whence) |
1da177e4 LT |
256 | { |
257 | loff_t (*fn)(struct file *, loff_t, int); | |
258 | ||
259 | fn = no_llseek; | |
260 | if (file->f_mode & FMODE_LSEEK) { | |
72c2d531 | 261 | if (file->f_op->llseek) |
1da177e4 LT |
262 | fn = file->f_op->llseek; |
263 | } | |
965c8e59 | 264 | return fn(file, offset, whence); |
1da177e4 LT |
265 | } |
266 | EXPORT_SYMBOL(vfs_llseek); | |
267 | ||
9c225f26 LT |
268 | static inline struct fd fdget_pos(int fd) |
269 | { | |
bd2a31d5 | 270 | return __to_fd(__fdget_pos(fd)); |
9c225f26 LT |
271 | } |
272 | ||
273 | static inline void fdput_pos(struct fd f) | |
274 | { | |
275 | if (f.flags & FDPUT_POS_UNLOCK) | |
276 | mutex_unlock(&f.file->f_pos_lock); | |
277 | fdput(f); | |
278 | } | |
279 | ||
965c8e59 | 280 | SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence) |
1da177e4 LT |
281 | { |
282 | off_t retval; | |
9c225f26 | 283 | struct fd f = fdget_pos(fd); |
2903ff01 AV |
284 | if (!f.file) |
285 | return -EBADF; | |
1da177e4 LT |
286 | |
287 | retval = -EINVAL; | |
965c8e59 AM |
288 | if (whence <= SEEK_MAX) { |
289 | loff_t res = vfs_llseek(f.file, offset, whence); | |
1da177e4 LT |
290 | retval = res; |
291 | if (res != (loff_t)retval) | |
292 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ | |
293 | } | |
9c225f26 | 294 | fdput_pos(f); |
1da177e4 LT |
295 | return retval; |
296 | } | |
297 | ||
561c6731 AV |
298 | #ifdef CONFIG_COMPAT |
299 | COMPAT_SYSCALL_DEFINE3(lseek, unsigned int, fd, compat_off_t, offset, unsigned int, whence) | |
300 | { | |
301 | return sys_lseek(fd, offset, whence); | |
302 | } | |
303 | #endif | |
304 | ||
1da177e4 | 305 | #ifdef __ARCH_WANT_SYS_LLSEEK |
003d7ab4 HC |
306 | SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, |
307 | unsigned long, offset_low, loff_t __user *, result, | |
965c8e59 | 308 | unsigned int, whence) |
1da177e4 LT |
309 | { |
310 | int retval; | |
d7a15f8d | 311 | struct fd f = fdget_pos(fd); |
1da177e4 | 312 | loff_t offset; |
1da177e4 | 313 | |
2903ff01 AV |
314 | if (!f.file) |
315 | return -EBADF; | |
1da177e4 LT |
316 | |
317 | retval = -EINVAL; | |
965c8e59 | 318 | if (whence > SEEK_MAX) |
1da177e4 LT |
319 | goto out_putf; |
320 | ||
2903ff01 | 321 | offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low, |
965c8e59 | 322 | whence); |
1da177e4 LT |
323 | |
324 | retval = (int)offset; | |
325 | if (offset >= 0) { | |
326 | retval = -EFAULT; | |
327 | if (!copy_to_user(result, &offset, sizeof(offset))) | |
328 | retval = 0; | |
329 | } | |
330 | out_putf: | |
d7a15f8d | 331 | fdput_pos(f); |
1da177e4 LT |
332 | return retval; |
333 | } | |
334 | #endif | |
335 | ||
e28cc715 LT |
336 | /* |
337 | * rw_verify_area doesn't like huge counts. We limit | |
338 | * them to something that fits in "int" so that others | |
339 | * won't have to do range checks all the time. | |
340 | */ | |
68d70d03 | 341 | int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count) |
1da177e4 LT |
342 | { |
343 | struct inode *inode; | |
344 | loff_t pos; | |
c43e259c | 345 | int retval = -EINVAL; |
1da177e4 | 346 | |
496ad9aa | 347 | inode = file_inode(file); |
e28cc715 | 348 | if (unlikely((ssize_t) count < 0)) |
c43e259c | 349 | return retval; |
1da177e4 | 350 | pos = *ppos; |
cccb5a1e AV |
351 | if (unlikely(pos < 0)) { |
352 | if (!unsigned_offsets(file)) | |
353 | return retval; | |
354 | if (count >= -pos) /* both values are in 0..LLONG_MAX */ | |
355 | return -EOVERFLOW; | |
356 | } else if (unlikely((loff_t) (pos + count) < 0)) { | |
357 | if (!unsigned_offsets(file)) | |
4a3956c7 KH |
358 | return retval; |
359 | } | |
1da177e4 | 360 | |
a16877ca | 361 | if (unlikely(inode->i_flock && mandatory_lock(inode))) { |
c43e259c | 362 | retval = locks_mandatory_area( |
e28cc715 LT |
363 | read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, |
364 | inode, file, pos, count); | |
365 | if (retval < 0) | |
366 | return retval; | |
367 | } | |
c43e259c JM |
368 | retval = security_file_permission(file, |
369 | read_write == READ ? MAY_READ : MAY_WRITE); | |
370 | if (retval) | |
371 | return retval; | |
e28cc715 | 372 | return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; |
1da177e4 LT |
373 | } |
374 | ||
375 | ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) | |
376 | { | |
027445c3 | 377 | struct iovec iov = { .iov_base = buf, .iov_len = len }; |
1da177e4 LT |
378 | struct kiocb kiocb; |
379 | ssize_t ret; | |
380 | ||
381 | init_sync_kiocb(&kiocb, filp); | |
382 | kiocb.ki_pos = *ppos; | |
61964eba | 383 | kiocb.ki_nbytes = len; |
027445c3 | 384 | |
41003a7b | 385 | ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); |
1da177e4 LT |
386 | if (-EIOCBQUEUED == ret) |
387 | ret = wait_on_sync_kiocb(&kiocb); | |
388 | *ppos = kiocb.ki_pos; | |
389 | return ret; | |
390 | } | |
391 | ||
392 | EXPORT_SYMBOL(do_sync_read); | |
393 | ||
293bc982 AV |
394 | ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
395 | { | |
396 | struct iovec iov = { .iov_base = buf, .iov_len = len }; | |
397 | struct kiocb kiocb; | |
398 | struct iov_iter iter; | |
399 | ssize_t ret; | |
400 | ||
401 | init_sync_kiocb(&kiocb, filp); | |
402 | kiocb.ki_pos = *ppos; | |
403 | kiocb.ki_nbytes = len; | |
404 | iov_iter_init(&iter, READ, &iov, 1, len); | |
405 | ||
406 | ret = filp->f_op->read_iter(&kiocb, &iter); | |
407 | if (-EIOCBQUEUED == ret) | |
408 | ret = wait_on_sync_kiocb(&kiocb); | |
409 | *ppos = kiocb.ki_pos; | |
410 | return ret; | |
411 | } | |
412 | ||
413 | EXPORT_SYMBOL(new_sync_read); | |
414 | ||
6fb5032e DK |
415 | ssize_t __vfs_read(struct file *file, char __user *buf, size_t count, |
416 | loff_t *pos) | |
417 | { | |
418 | ssize_t ret; | |
419 | ||
420 | if (file->f_op->read) | |
421 | ret = file->f_op->read(file, buf, count, pos); | |
422 | else if (file->f_op->aio_read) | |
423 | ret = do_sync_read(file, buf, count, pos); | |
424 | else if (file->f_op->read_iter) | |
425 | ret = new_sync_read(file, buf, count, pos); | |
426 | else | |
427 | ret = -EINVAL; | |
428 | ||
429 | return ret; | |
430 | } | |
431 | ||
1da177e4 LT |
432 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) |
433 | { | |
434 | ssize_t ret; | |
435 | ||
436 | if (!(file->f_mode & FMODE_READ)) | |
437 | return -EBADF; | |
7f7f25e8 | 438 | if (!(file->f_mode & FMODE_CAN_READ)) |
1da177e4 LT |
439 | return -EINVAL; |
440 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) | |
441 | return -EFAULT; | |
442 | ||
443 | ret = rw_verify_area(READ, file, pos, count); | |
e28cc715 LT |
444 | if (ret >= 0) { |
445 | count = ret; | |
6fb5032e | 446 | ret = __vfs_read(file, buf, count, pos); |
c43e259c | 447 | if (ret > 0) { |
2a12a9d7 | 448 | fsnotify_access(file); |
c43e259c | 449 | add_rchar(current, ret); |
1da177e4 | 450 | } |
c43e259c | 451 | inc_syscr(current); |
1da177e4 LT |
452 | } |
453 | ||
454 | return ret; | |
455 | } | |
456 | ||
457 | EXPORT_SYMBOL(vfs_read); | |
458 | ||
459 | ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) | |
460 | { | |
027445c3 | 461 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; |
1da177e4 LT |
462 | struct kiocb kiocb; |
463 | ssize_t ret; | |
464 | ||
465 | init_sync_kiocb(&kiocb, filp); | |
466 | kiocb.ki_pos = *ppos; | |
61964eba | 467 | kiocb.ki_nbytes = len; |
027445c3 | 468 | |
41003a7b | 469 | ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); |
1da177e4 LT |
470 | if (-EIOCBQUEUED == ret) |
471 | ret = wait_on_sync_kiocb(&kiocb); | |
472 | *ppos = kiocb.ki_pos; | |
473 | return ret; | |
474 | } | |
475 | ||
476 | EXPORT_SYMBOL(do_sync_write); | |
477 | ||
293bc982 AV |
478 | ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) |
479 | { | |
480 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; | |
481 | struct kiocb kiocb; | |
482 | struct iov_iter iter; | |
483 | ssize_t ret; | |
484 | ||
485 | init_sync_kiocb(&kiocb, filp); | |
486 | kiocb.ki_pos = *ppos; | |
487 | kiocb.ki_nbytes = len; | |
488 | iov_iter_init(&iter, WRITE, &iov, 1, len); | |
489 | ||
490 | ret = filp->f_op->write_iter(&kiocb, &iter); | |
491 | if (-EIOCBQUEUED == ret) | |
492 | ret = wait_on_sync_kiocb(&kiocb); | |
493 | *ppos = kiocb.ki_pos; | |
494 | return ret; | |
495 | } | |
496 | ||
497 | EXPORT_SYMBOL(new_sync_write); | |
498 | ||
06ae43f3 AV |
499 | ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos) |
500 | { | |
501 | mm_segment_t old_fs; | |
502 | const char __user *p; | |
503 | ssize_t ret; | |
504 | ||
7f7f25e8 | 505 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
3e84f48e AV |
506 | return -EINVAL; |
507 | ||
06ae43f3 AV |
508 | old_fs = get_fs(); |
509 | set_fs(get_ds()); | |
510 | p = (__force const char __user *)buf; | |
511 | if (count > MAX_RW_COUNT) | |
512 | count = MAX_RW_COUNT; | |
513 | if (file->f_op->write) | |
514 | ret = file->f_op->write(file, p, count, pos); | |
293bc982 | 515 | else if (file->f_op->aio_write) |
06ae43f3 | 516 | ret = do_sync_write(file, p, count, pos); |
293bc982 AV |
517 | else |
518 | ret = new_sync_write(file, p, count, pos); | |
06ae43f3 AV |
519 | set_fs(old_fs); |
520 | if (ret > 0) { | |
521 | fsnotify_modify(file); | |
522 | add_wchar(current, ret); | |
523 | } | |
524 | inc_syscw(current); | |
525 | return ret; | |
526 | } | |
527 | ||
2ec3a12a AV |
528 | EXPORT_SYMBOL(__kernel_write); |
529 | ||
1da177e4 LT |
530 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
531 | { | |
532 | ssize_t ret; | |
533 | ||
534 | if (!(file->f_mode & FMODE_WRITE)) | |
535 | return -EBADF; | |
7f7f25e8 | 536 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
1da177e4 LT |
537 | return -EINVAL; |
538 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) | |
539 | return -EFAULT; | |
540 | ||
541 | ret = rw_verify_area(WRITE, file, pos, count); | |
e28cc715 LT |
542 | if (ret >= 0) { |
543 | count = ret; | |
03d95eb2 | 544 | file_start_write(file); |
c43e259c JM |
545 | if (file->f_op->write) |
546 | ret = file->f_op->write(file, buf, count, pos); | |
293bc982 | 547 | else if (file->f_op->aio_write) |
c43e259c | 548 | ret = do_sync_write(file, buf, count, pos); |
293bc982 AV |
549 | else |
550 | ret = new_sync_write(file, buf, count, pos); | |
c43e259c | 551 | if (ret > 0) { |
2a12a9d7 | 552 | fsnotify_modify(file); |
c43e259c | 553 | add_wchar(current, ret); |
1da177e4 | 554 | } |
c43e259c | 555 | inc_syscw(current); |
03d95eb2 | 556 | file_end_write(file); |
1da177e4 LT |
557 | } |
558 | ||
559 | return ret; | |
560 | } | |
561 | ||
562 | EXPORT_SYMBOL(vfs_write); | |
563 | ||
564 | static inline loff_t file_pos_read(struct file *file) | |
565 | { | |
566 | return file->f_pos; | |
567 | } | |
568 | ||
569 | static inline void file_pos_write(struct file *file, loff_t pos) | |
570 | { | |
571 | file->f_pos = pos; | |
572 | } | |
573 | ||
3cdad428 | 574 | SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) |
1da177e4 | 575 | { |
9c225f26 | 576 | struct fd f = fdget_pos(fd); |
1da177e4 | 577 | ssize_t ret = -EBADF; |
1da177e4 | 578 | |
2903ff01 AV |
579 | if (f.file) { |
580 | loff_t pos = file_pos_read(f.file); | |
581 | ret = vfs_read(f.file, buf, count, &pos); | |
5faf153e AV |
582 | if (ret >= 0) |
583 | file_pos_write(f.file, pos); | |
9c225f26 | 584 | fdput_pos(f); |
1da177e4 | 585 | } |
1da177e4 LT |
586 | return ret; |
587 | } | |
1da177e4 | 588 | |
3cdad428 HC |
589 | SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, |
590 | size_t, count) | |
1da177e4 | 591 | { |
9c225f26 | 592 | struct fd f = fdget_pos(fd); |
1da177e4 | 593 | ssize_t ret = -EBADF; |
1da177e4 | 594 | |
2903ff01 AV |
595 | if (f.file) { |
596 | loff_t pos = file_pos_read(f.file); | |
597 | ret = vfs_write(f.file, buf, count, &pos); | |
5faf153e AV |
598 | if (ret >= 0) |
599 | file_pos_write(f.file, pos); | |
9c225f26 | 600 | fdput_pos(f); |
1da177e4 LT |
601 | } |
602 | ||
603 | return ret; | |
604 | } | |
605 | ||
4a0fd5bf AV |
606 | SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, |
607 | size_t, count, loff_t, pos) | |
1da177e4 | 608 | { |
2903ff01 | 609 | struct fd f; |
1da177e4 | 610 | ssize_t ret = -EBADF; |
1da177e4 LT |
611 | |
612 | if (pos < 0) | |
613 | return -EINVAL; | |
614 | ||
2903ff01 AV |
615 | f = fdget(fd); |
616 | if (f.file) { | |
1da177e4 | 617 | ret = -ESPIPE; |
2903ff01 AV |
618 | if (f.file->f_mode & FMODE_PREAD) |
619 | ret = vfs_read(f.file, buf, count, &pos); | |
620 | fdput(f); | |
1da177e4 LT |
621 | } |
622 | ||
623 | return ret; | |
624 | } | |
625 | ||
4a0fd5bf AV |
626 | SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, |
627 | size_t, count, loff_t, pos) | |
1da177e4 | 628 | { |
2903ff01 | 629 | struct fd f; |
1da177e4 | 630 | ssize_t ret = -EBADF; |
1da177e4 LT |
631 | |
632 | if (pos < 0) | |
633 | return -EINVAL; | |
634 | ||
2903ff01 AV |
635 | f = fdget(fd); |
636 | if (f.file) { | |
1da177e4 | 637 | ret = -ESPIPE; |
2903ff01 AV |
638 | if (f.file->f_mode & FMODE_PWRITE) |
639 | ret = vfs_write(f.file, buf, count, &pos); | |
640 | fdput(f); | |
1da177e4 LT |
641 | } |
642 | ||
643 | return ret; | |
644 | } | |
645 | ||
646 | /* | |
647 | * Reduce an iovec's length in-place. Return the resulting number of segments | |
648 | */ | |
649 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) | |
650 | { | |
651 | unsigned long seg = 0; | |
652 | size_t len = 0; | |
653 | ||
654 | while (seg < nr_segs) { | |
655 | seg++; | |
656 | if (len + iov->iov_len >= to) { | |
657 | iov->iov_len = to - len; | |
658 | break; | |
659 | } | |
660 | len += iov->iov_len; | |
661 | iov++; | |
662 | } | |
663 | return seg; | |
664 | } | |
19295529 | 665 | EXPORT_SYMBOL(iov_shorten); |
1da177e4 | 666 | |
293bc982 AV |
667 | static ssize_t do_iter_readv_writev(struct file *filp, int rw, const struct iovec *iov, |
668 | unsigned long nr_segs, size_t len, loff_t *ppos, iter_fn_t fn) | |
669 | { | |
670 | struct kiocb kiocb; | |
671 | struct iov_iter iter; | |
672 | ssize_t ret; | |
673 | ||
674 | init_sync_kiocb(&kiocb, filp); | |
675 | kiocb.ki_pos = *ppos; | |
676 | kiocb.ki_nbytes = len; | |
677 | ||
678 | iov_iter_init(&iter, rw, iov, nr_segs, len); | |
679 | ret = fn(&kiocb, &iter); | |
680 | if (ret == -EIOCBQUEUED) | |
681 | ret = wait_on_sync_kiocb(&kiocb); | |
682 | *ppos = kiocb.ki_pos; | |
683 | return ret; | |
684 | } | |
685 | ||
72ec3516 | 686 | static ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, |
ee0b3e67 BP |
687 | unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) |
688 | { | |
689 | struct kiocb kiocb; | |
690 | ssize_t ret; | |
691 | ||
692 | init_sync_kiocb(&kiocb, filp); | |
693 | kiocb.ki_pos = *ppos; | |
ee0b3e67 BP |
694 | kiocb.ki_nbytes = len; |
695 | ||
41003a7b | 696 | ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); |
ee0b3e67 BP |
697 | if (ret == -EIOCBQUEUED) |
698 | ret = wait_on_sync_kiocb(&kiocb); | |
699 | *ppos = kiocb.ki_pos; | |
700 | return ret; | |
701 | } | |
702 | ||
703 | /* Do it by hand, with file-ops */ | |
72ec3516 | 704 | static ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, |
ee0b3e67 BP |
705 | unsigned long nr_segs, loff_t *ppos, io_fn_t fn) |
706 | { | |
707 | struct iovec *vector = iov; | |
708 | ssize_t ret = 0; | |
709 | ||
710 | while (nr_segs > 0) { | |
711 | void __user *base; | |
712 | size_t len; | |
713 | ssize_t nr; | |
714 | ||
715 | base = vector->iov_base; | |
716 | len = vector->iov_len; | |
717 | vector++; | |
718 | nr_segs--; | |
719 | ||
720 | nr = fn(filp, base, len, ppos); | |
721 | ||
722 | if (nr < 0) { | |
723 | if (!ret) | |
724 | ret = nr; | |
725 | break; | |
726 | } | |
727 | ret += nr; | |
728 | if (nr != len) | |
729 | break; | |
730 | } | |
731 | ||
732 | return ret; | |
733 | } | |
734 | ||
1da177e4 LT |
735 | /* A write operation does a read from user space and vice versa */ |
736 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) | |
737 | ||
eed4e51f BP |
738 | ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, |
739 | unsigned long nr_segs, unsigned long fast_segs, | |
740 | struct iovec *fast_pointer, | |
ac34ebb3 | 741 | struct iovec **ret_pointer) |
435f49a5 | 742 | { |
eed4e51f | 743 | unsigned long seg; |
435f49a5 | 744 | ssize_t ret; |
eed4e51f BP |
745 | struct iovec *iov = fast_pointer; |
746 | ||
435f49a5 LT |
747 | /* |
748 | * SuS says "The readv() function *may* fail if the iovcnt argument | |
749 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has | |
750 | * traditionally returned zero for zero segments, so... | |
751 | */ | |
eed4e51f BP |
752 | if (nr_segs == 0) { |
753 | ret = 0; | |
435f49a5 | 754 | goto out; |
eed4e51f BP |
755 | } |
756 | ||
435f49a5 LT |
757 | /* |
758 | * First get the "struct iovec" from user memory and | |
759 | * verify all the pointers | |
760 | */ | |
eed4e51f BP |
761 | if (nr_segs > UIO_MAXIOV) { |
762 | ret = -EINVAL; | |
435f49a5 | 763 | goto out; |
eed4e51f BP |
764 | } |
765 | if (nr_segs > fast_segs) { | |
435f49a5 | 766 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); |
eed4e51f BP |
767 | if (iov == NULL) { |
768 | ret = -ENOMEM; | |
435f49a5 | 769 | goto out; |
eed4e51f | 770 | } |
435f49a5 | 771 | } |
eed4e51f BP |
772 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { |
773 | ret = -EFAULT; | |
435f49a5 | 774 | goto out; |
eed4e51f BP |
775 | } |
776 | ||
435f49a5 | 777 | /* |
eed4e51f BP |
778 | * According to the Single Unix Specification we should return EINVAL |
779 | * if an element length is < 0 when cast to ssize_t or if the | |
780 | * total length would overflow the ssize_t return value of the | |
781 | * system call. | |
435f49a5 LT |
782 | * |
783 | * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the | |
784 | * overflow case. | |
785 | */ | |
eed4e51f | 786 | ret = 0; |
435f49a5 LT |
787 | for (seg = 0; seg < nr_segs; seg++) { |
788 | void __user *buf = iov[seg].iov_base; | |
789 | ssize_t len = (ssize_t)iov[seg].iov_len; | |
eed4e51f BP |
790 | |
791 | /* see if we we're about to use an invalid len or if | |
792 | * it's about to overflow ssize_t */ | |
435f49a5 | 793 | if (len < 0) { |
eed4e51f | 794 | ret = -EINVAL; |
435f49a5 | 795 | goto out; |
eed4e51f | 796 | } |
ac34ebb3 | 797 | if (type >= 0 |
fcf63409 | 798 | && unlikely(!access_ok(vrfy_dir(type), buf, len))) { |
eed4e51f | 799 | ret = -EFAULT; |
435f49a5 LT |
800 | goto out; |
801 | } | |
802 | if (len > MAX_RW_COUNT - ret) { | |
803 | len = MAX_RW_COUNT - ret; | |
804 | iov[seg].iov_len = len; | |
eed4e51f | 805 | } |
eed4e51f | 806 | ret += len; |
435f49a5 | 807 | } |
eed4e51f BP |
808 | out: |
809 | *ret_pointer = iov; | |
810 | return ret; | |
811 | } | |
812 | ||
1da177e4 LT |
813 | static ssize_t do_readv_writev(int type, struct file *file, |
814 | const struct iovec __user * uvector, | |
815 | unsigned long nr_segs, loff_t *pos) | |
816 | { | |
1da177e4 LT |
817 | size_t tot_len; |
818 | struct iovec iovstack[UIO_FASTIOV]; | |
ee0b3e67 | 819 | struct iovec *iov = iovstack; |
1da177e4 | 820 | ssize_t ret; |
1da177e4 LT |
821 | io_fn_t fn; |
822 | iov_fn_t fnv; | |
293bc982 | 823 | iter_fn_t iter_fn; |
1da177e4 | 824 | |
eed4e51f | 825 | ret = rw_copy_check_uvector(type, uvector, nr_segs, |
ac34ebb3 | 826 | ARRAY_SIZE(iovstack), iovstack, &iov); |
eed4e51f | 827 | if (ret <= 0) |
1da177e4 | 828 | goto out; |
1da177e4 | 829 | |
eed4e51f | 830 | tot_len = ret; |
1da177e4 | 831 | ret = rw_verify_area(type, file, pos, tot_len); |
e28cc715 | 832 | if (ret < 0) |
411b67b4 | 833 | goto out; |
1da177e4 LT |
834 | |
835 | fnv = NULL; | |
836 | if (type == READ) { | |
837 | fn = file->f_op->read; | |
ee0b3e67 | 838 | fnv = file->f_op->aio_read; |
293bc982 | 839 | iter_fn = file->f_op->read_iter; |
1da177e4 LT |
840 | } else { |
841 | fn = (io_fn_t)file->f_op->write; | |
ee0b3e67 | 842 | fnv = file->f_op->aio_write; |
293bc982 | 843 | iter_fn = file->f_op->write_iter; |
03d95eb2 | 844 | file_start_write(file); |
1da177e4 LT |
845 | } |
846 | ||
293bc982 AV |
847 | if (iter_fn) |
848 | ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len, | |
849 | pos, iter_fn); | |
850 | else if (fnv) | |
ee0b3e67 BP |
851 | ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, |
852 | pos, fnv); | |
853 | else | |
854 | ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); | |
1da177e4 | 855 | |
03d95eb2 AV |
856 | if (type != READ) |
857 | file_end_write(file); | |
858 | ||
1da177e4 LT |
859 | out: |
860 | if (iov != iovstack) | |
861 | kfree(iov); | |
0eeca283 RL |
862 | if ((ret + (type == READ)) > 0) { |
863 | if (type == READ) | |
2a12a9d7 | 864 | fsnotify_access(file); |
0eeca283 | 865 | else |
2a12a9d7 | 866 | fsnotify_modify(file); |
0eeca283 | 867 | } |
1da177e4 | 868 | return ret; |
1da177e4 LT |
869 | } |
870 | ||
871 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, | |
872 | unsigned long vlen, loff_t *pos) | |
873 | { | |
874 | if (!(file->f_mode & FMODE_READ)) | |
875 | return -EBADF; | |
7f7f25e8 | 876 | if (!(file->f_mode & FMODE_CAN_READ)) |
1da177e4 LT |
877 | return -EINVAL; |
878 | ||
879 | return do_readv_writev(READ, file, vec, vlen, pos); | |
880 | } | |
881 | ||
882 | EXPORT_SYMBOL(vfs_readv); | |
883 | ||
884 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, | |
885 | unsigned long vlen, loff_t *pos) | |
886 | { | |
887 | if (!(file->f_mode & FMODE_WRITE)) | |
888 | return -EBADF; | |
7f7f25e8 | 889 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
1da177e4 LT |
890 | return -EINVAL; |
891 | ||
892 | return do_readv_writev(WRITE, file, vec, vlen, pos); | |
893 | } | |
894 | ||
895 | EXPORT_SYMBOL(vfs_writev); | |
896 | ||
3cdad428 HC |
897 | SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, |
898 | unsigned long, vlen) | |
1da177e4 | 899 | { |
9c225f26 | 900 | struct fd f = fdget_pos(fd); |
1da177e4 | 901 | ssize_t ret = -EBADF; |
1da177e4 | 902 | |
2903ff01 AV |
903 | if (f.file) { |
904 | loff_t pos = file_pos_read(f.file); | |
905 | ret = vfs_readv(f.file, vec, vlen, &pos); | |
5faf153e AV |
906 | if (ret >= 0) |
907 | file_pos_write(f.file, pos); | |
9c225f26 | 908 | fdput_pos(f); |
1da177e4 LT |
909 | } |
910 | ||
911 | if (ret > 0) | |
4b98d11b AD |
912 | add_rchar(current, ret); |
913 | inc_syscr(current); | |
1da177e4 LT |
914 | return ret; |
915 | } | |
916 | ||
3cdad428 HC |
917 | SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, |
918 | unsigned long, vlen) | |
1da177e4 | 919 | { |
9c225f26 | 920 | struct fd f = fdget_pos(fd); |
1da177e4 | 921 | ssize_t ret = -EBADF; |
1da177e4 | 922 | |
2903ff01 AV |
923 | if (f.file) { |
924 | loff_t pos = file_pos_read(f.file); | |
925 | ret = vfs_writev(f.file, vec, vlen, &pos); | |
5faf153e AV |
926 | if (ret >= 0) |
927 | file_pos_write(f.file, pos); | |
9c225f26 | 928 | fdput_pos(f); |
1da177e4 LT |
929 | } |
930 | ||
931 | if (ret > 0) | |
4b98d11b AD |
932 | add_wchar(current, ret); |
933 | inc_syscw(current); | |
1da177e4 LT |
934 | return ret; |
935 | } | |
936 | ||
601cc11d LT |
937 | static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) |
938 | { | |
939 | #define HALF_LONG_BITS (BITS_PER_LONG / 2) | |
940 | return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; | |
941 | } | |
942 | ||
f3554f4b | 943 | SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, |
601cc11d | 944 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
f3554f4b | 945 | { |
601cc11d | 946 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
2903ff01 | 947 | struct fd f; |
f3554f4b | 948 | ssize_t ret = -EBADF; |
f3554f4b GH |
949 | |
950 | if (pos < 0) | |
951 | return -EINVAL; | |
952 | ||
2903ff01 AV |
953 | f = fdget(fd); |
954 | if (f.file) { | |
f3554f4b | 955 | ret = -ESPIPE; |
2903ff01 AV |
956 | if (f.file->f_mode & FMODE_PREAD) |
957 | ret = vfs_readv(f.file, vec, vlen, &pos); | |
958 | fdput(f); | |
f3554f4b GH |
959 | } |
960 | ||
961 | if (ret > 0) | |
962 | add_rchar(current, ret); | |
963 | inc_syscr(current); | |
964 | return ret; | |
965 | } | |
966 | ||
967 | SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, | |
601cc11d | 968 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
f3554f4b | 969 | { |
601cc11d | 970 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
2903ff01 | 971 | struct fd f; |
f3554f4b | 972 | ssize_t ret = -EBADF; |
f3554f4b GH |
973 | |
974 | if (pos < 0) | |
975 | return -EINVAL; | |
976 | ||
2903ff01 AV |
977 | f = fdget(fd); |
978 | if (f.file) { | |
f3554f4b | 979 | ret = -ESPIPE; |
2903ff01 AV |
980 | if (f.file->f_mode & FMODE_PWRITE) |
981 | ret = vfs_writev(f.file, vec, vlen, &pos); | |
982 | fdput(f); | |
f3554f4b GH |
983 | } |
984 | ||
985 | if (ret > 0) | |
986 | add_wchar(current, ret); | |
987 | inc_syscw(current); | |
988 | return ret; | |
989 | } | |
990 | ||
72ec3516 AV |
991 | #ifdef CONFIG_COMPAT |
992 | ||
993 | static ssize_t compat_do_readv_writev(int type, struct file *file, | |
994 | const struct compat_iovec __user *uvector, | |
995 | unsigned long nr_segs, loff_t *pos) | |
996 | { | |
997 | compat_ssize_t tot_len; | |
998 | struct iovec iovstack[UIO_FASTIOV]; | |
999 | struct iovec *iov = iovstack; | |
1000 | ssize_t ret; | |
1001 | io_fn_t fn; | |
1002 | iov_fn_t fnv; | |
293bc982 | 1003 | iter_fn_t iter_fn; |
72ec3516 | 1004 | |
72ec3516 AV |
1005 | ret = compat_rw_copy_check_uvector(type, uvector, nr_segs, |
1006 | UIO_FASTIOV, iovstack, &iov); | |
1007 | if (ret <= 0) | |
1008 | goto out; | |
1009 | ||
1010 | tot_len = ret; | |
1011 | ret = rw_verify_area(type, file, pos, tot_len); | |
1012 | if (ret < 0) | |
1013 | goto out; | |
1014 | ||
1015 | fnv = NULL; | |
1016 | if (type == READ) { | |
1017 | fn = file->f_op->read; | |
1018 | fnv = file->f_op->aio_read; | |
293bc982 | 1019 | iter_fn = file->f_op->read_iter; |
72ec3516 AV |
1020 | } else { |
1021 | fn = (io_fn_t)file->f_op->write; | |
1022 | fnv = file->f_op->aio_write; | |
293bc982 | 1023 | iter_fn = file->f_op->write_iter; |
03d95eb2 | 1024 | file_start_write(file); |
72ec3516 AV |
1025 | } |
1026 | ||
293bc982 AV |
1027 | if (iter_fn) |
1028 | ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len, | |
1029 | pos, iter_fn); | |
1030 | else if (fnv) | |
72ec3516 AV |
1031 | ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, |
1032 | pos, fnv); | |
03d95eb2 | 1033 | else |
72ec3516 AV |
1034 | ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); |
1035 | ||
03d95eb2 AV |
1036 | if (type != READ) |
1037 | file_end_write(file); | |
1038 | ||
72ec3516 AV |
1039 | out: |
1040 | if (iov != iovstack) | |
1041 | kfree(iov); | |
1042 | if ((ret + (type == READ)) > 0) { | |
1043 | if (type == READ) | |
1044 | fsnotify_access(file); | |
1045 | else | |
1046 | fsnotify_modify(file); | |
1047 | } | |
1048 | return ret; | |
1049 | } | |
1050 | ||
1051 | static size_t compat_readv(struct file *file, | |
1052 | const struct compat_iovec __user *vec, | |
1053 | unsigned long vlen, loff_t *pos) | |
1054 | { | |
1055 | ssize_t ret = -EBADF; | |
1056 | ||
1057 | if (!(file->f_mode & FMODE_READ)) | |
1058 | goto out; | |
1059 | ||
1060 | ret = -EINVAL; | |
7f7f25e8 | 1061 | if (!(file->f_mode & FMODE_CAN_READ)) |
72ec3516 AV |
1062 | goto out; |
1063 | ||
1064 | ret = compat_do_readv_writev(READ, file, vec, vlen, pos); | |
1065 | ||
1066 | out: | |
1067 | if (ret > 0) | |
1068 | add_rchar(current, ret); | |
1069 | inc_syscr(current); | |
1070 | return ret; | |
1071 | } | |
1072 | ||
dfd948e3 | 1073 | COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, |
72ec3516 | 1074 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1075 | compat_ulong_t, vlen) |
72ec3516 | 1076 | { |
9c225f26 | 1077 | struct fd f = fdget_pos(fd); |
72ec3516 AV |
1078 | ssize_t ret; |
1079 | loff_t pos; | |
1080 | ||
1081 | if (!f.file) | |
1082 | return -EBADF; | |
1083 | pos = f.file->f_pos; | |
1084 | ret = compat_readv(f.file, vec, vlen, &pos); | |
5faf153e AV |
1085 | if (ret >= 0) |
1086 | f.file->f_pos = pos; | |
9c225f26 | 1087 | fdput_pos(f); |
72ec3516 AV |
1088 | return ret; |
1089 | } | |
1090 | ||
378a10f3 HC |
1091 | static long __compat_sys_preadv64(unsigned long fd, |
1092 | const struct compat_iovec __user *vec, | |
1093 | unsigned long vlen, loff_t pos) | |
72ec3516 AV |
1094 | { |
1095 | struct fd f; | |
1096 | ssize_t ret; | |
1097 | ||
1098 | if (pos < 0) | |
1099 | return -EINVAL; | |
1100 | f = fdget(fd); | |
1101 | if (!f.file) | |
1102 | return -EBADF; | |
1103 | ret = -ESPIPE; | |
1104 | if (f.file->f_mode & FMODE_PREAD) | |
1105 | ret = compat_readv(f.file, vec, vlen, &pos); | |
1106 | fdput(f); | |
1107 | return ret; | |
1108 | } | |
1109 | ||
378a10f3 HC |
1110 | #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64 |
1111 | COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, | |
1112 | const struct compat_iovec __user *,vec, | |
1113 | unsigned long, vlen, loff_t, pos) | |
1114 | { | |
1115 | return __compat_sys_preadv64(fd, vec, vlen, pos); | |
1116 | } | |
1117 | #endif | |
1118 | ||
dfd948e3 | 1119 | COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, |
72ec3516 | 1120 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1121 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1122 | { |
1123 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 HC |
1124 | |
1125 | return __compat_sys_preadv64(fd, vec, vlen, pos); | |
72ec3516 AV |
1126 | } |
1127 | ||
1128 | static size_t compat_writev(struct file *file, | |
1129 | const struct compat_iovec __user *vec, | |
1130 | unsigned long vlen, loff_t *pos) | |
1131 | { | |
1132 | ssize_t ret = -EBADF; | |
1133 | ||
1134 | if (!(file->f_mode & FMODE_WRITE)) | |
1135 | goto out; | |
1136 | ||
1137 | ret = -EINVAL; | |
7f7f25e8 | 1138 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
72ec3516 AV |
1139 | goto out; |
1140 | ||
1141 | ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos); | |
1142 | ||
1143 | out: | |
1144 | if (ret > 0) | |
1145 | add_wchar(current, ret); | |
1146 | inc_syscw(current); | |
1147 | return ret; | |
1148 | } | |
1149 | ||
dfd948e3 | 1150 | COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, |
72ec3516 | 1151 | const struct compat_iovec __user *, vec, |
dfd948e3 | 1152 | compat_ulong_t, vlen) |
72ec3516 | 1153 | { |
9c225f26 | 1154 | struct fd f = fdget_pos(fd); |
72ec3516 AV |
1155 | ssize_t ret; |
1156 | loff_t pos; | |
1157 | ||
1158 | if (!f.file) | |
1159 | return -EBADF; | |
1160 | pos = f.file->f_pos; | |
1161 | ret = compat_writev(f.file, vec, vlen, &pos); | |
5faf153e AV |
1162 | if (ret >= 0) |
1163 | f.file->f_pos = pos; | |
9c225f26 | 1164 | fdput_pos(f); |
72ec3516 AV |
1165 | return ret; |
1166 | } | |
1167 | ||
378a10f3 HC |
1168 | static long __compat_sys_pwritev64(unsigned long fd, |
1169 | const struct compat_iovec __user *vec, | |
1170 | unsigned long vlen, loff_t pos) | |
72ec3516 AV |
1171 | { |
1172 | struct fd f; | |
1173 | ssize_t ret; | |
1174 | ||
1175 | if (pos < 0) | |
1176 | return -EINVAL; | |
1177 | f = fdget(fd); | |
1178 | if (!f.file) | |
1179 | return -EBADF; | |
1180 | ret = -ESPIPE; | |
1181 | if (f.file->f_mode & FMODE_PWRITE) | |
1182 | ret = compat_writev(f.file, vec, vlen, &pos); | |
1183 | fdput(f); | |
1184 | return ret; | |
1185 | } | |
1186 | ||
378a10f3 HC |
1187 | #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64 |
1188 | COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, | |
1189 | const struct compat_iovec __user *,vec, | |
1190 | unsigned long, vlen, loff_t, pos) | |
1191 | { | |
1192 | return __compat_sys_pwritev64(fd, vec, vlen, pos); | |
1193 | } | |
1194 | #endif | |
1195 | ||
dfd948e3 | 1196 | COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, |
72ec3516 | 1197 | const struct compat_iovec __user *,vec, |
dfd948e3 | 1198 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
72ec3516 AV |
1199 | { |
1200 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; | |
378a10f3 HC |
1201 | |
1202 | return __compat_sys_pwritev64(fd, vec, vlen, pos); | |
72ec3516 AV |
1203 | } |
1204 | #endif | |
1205 | ||
19f4fc3a AV |
1206 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, |
1207 | size_t count, loff_t max) | |
1da177e4 | 1208 | { |
2903ff01 AV |
1209 | struct fd in, out; |
1210 | struct inode *in_inode, *out_inode; | |
1da177e4 | 1211 | loff_t pos; |
7995bd28 | 1212 | loff_t out_pos; |
1da177e4 | 1213 | ssize_t retval; |
2903ff01 | 1214 | int fl; |
1da177e4 LT |
1215 | |
1216 | /* | |
1217 | * Get input file, and verify that it is ok.. | |
1218 | */ | |
1219 | retval = -EBADF; | |
2903ff01 AV |
1220 | in = fdget(in_fd); |
1221 | if (!in.file) | |
1da177e4 | 1222 | goto out; |
2903ff01 | 1223 | if (!(in.file->f_mode & FMODE_READ)) |
1da177e4 | 1224 | goto fput_in; |
1da177e4 | 1225 | retval = -ESPIPE; |
7995bd28 AV |
1226 | if (!ppos) { |
1227 | pos = in.file->f_pos; | |
1228 | } else { | |
1229 | pos = *ppos; | |
2903ff01 | 1230 | if (!(in.file->f_mode & FMODE_PREAD)) |
1da177e4 | 1231 | goto fput_in; |
7995bd28 AV |
1232 | } |
1233 | retval = rw_verify_area(READ, in.file, &pos, count); | |
e28cc715 | 1234 | if (retval < 0) |
1da177e4 | 1235 | goto fput_in; |
e28cc715 | 1236 | count = retval; |
1da177e4 | 1237 | |
1da177e4 LT |
1238 | /* |
1239 | * Get output file, and verify that it is ok.. | |
1240 | */ | |
1241 | retval = -EBADF; | |
2903ff01 AV |
1242 | out = fdget(out_fd); |
1243 | if (!out.file) | |
1da177e4 | 1244 | goto fput_in; |
2903ff01 | 1245 | if (!(out.file->f_mode & FMODE_WRITE)) |
1da177e4 LT |
1246 | goto fput_out; |
1247 | retval = -EINVAL; | |
496ad9aa AV |
1248 | in_inode = file_inode(in.file); |
1249 | out_inode = file_inode(out.file); | |
7995bd28 AV |
1250 | out_pos = out.file->f_pos; |
1251 | retval = rw_verify_area(WRITE, out.file, &out_pos, count); | |
e28cc715 | 1252 | if (retval < 0) |
1da177e4 | 1253 | goto fput_out; |
e28cc715 | 1254 | count = retval; |
1da177e4 | 1255 | |
1da177e4 LT |
1256 | if (!max) |
1257 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); | |
1258 | ||
1da177e4 LT |
1259 | if (unlikely(pos + count > max)) { |
1260 | retval = -EOVERFLOW; | |
1261 | if (pos >= max) | |
1262 | goto fput_out; | |
1263 | count = max - pos; | |
1264 | } | |
1265 | ||
d96e6e71 | 1266 | fl = 0; |
534f2aaa | 1267 | #if 0 |
d96e6e71 JA |
1268 | /* |
1269 | * We need to debate whether we can enable this or not. The | |
1270 | * man page documents EAGAIN return for the output at least, | |
1271 | * and the application is arguably buggy if it doesn't expect | |
1272 | * EAGAIN on a non-blocking file descriptor. | |
1273 | */ | |
2903ff01 | 1274 | if (in.file->f_flags & O_NONBLOCK) |
d96e6e71 | 1275 | fl = SPLICE_F_NONBLOCK; |
534f2aaa | 1276 | #endif |
50cd2c57 | 1277 | file_start_write(out.file); |
7995bd28 | 1278 | retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl); |
50cd2c57 | 1279 | file_end_write(out.file); |
1da177e4 LT |
1280 | |
1281 | if (retval > 0) { | |
4b98d11b AD |
1282 | add_rchar(current, retval); |
1283 | add_wchar(current, retval); | |
a68c2f12 SW |
1284 | fsnotify_access(in.file); |
1285 | fsnotify_modify(out.file); | |
7995bd28 AV |
1286 | out.file->f_pos = out_pos; |
1287 | if (ppos) | |
1288 | *ppos = pos; | |
1289 | else | |
1290 | in.file->f_pos = pos; | |
1da177e4 | 1291 | } |
1da177e4 | 1292 | |
4b98d11b AD |
1293 | inc_syscr(current); |
1294 | inc_syscw(current); | |
7995bd28 | 1295 | if (pos > max) |
1da177e4 LT |
1296 | retval = -EOVERFLOW; |
1297 | ||
1298 | fput_out: | |
2903ff01 | 1299 | fdput(out); |
1da177e4 | 1300 | fput_in: |
2903ff01 | 1301 | fdput(in); |
1da177e4 LT |
1302 | out: |
1303 | return retval; | |
1304 | } | |
1305 | ||
002c8976 | 1306 | SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count) |
1da177e4 LT |
1307 | { |
1308 | loff_t pos; | |
1309 | off_t off; | |
1310 | ssize_t ret; | |
1311 | ||
1312 | if (offset) { | |
1313 | if (unlikely(get_user(off, offset))) | |
1314 | return -EFAULT; | |
1315 | pos = off; | |
1316 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1317 | if (unlikely(put_user(pos, offset))) | |
1318 | return -EFAULT; | |
1319 | return ret; | |
1320 | } | |
1321 | ||
1322 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1323 | } | |
1324 | ||
002c8976 | 1325 | SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count) |
1da177e4 LT |
1326 | { |
1327 | loff_t pos; | |
1328 | ssize_t ret; | |
1329 | ||
1330 | if (offset) { | |
1331 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1332 | return -EFAULT; | |
1333 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1334 | if (unlikely(put_user(pos, offset))) | |
1335 | return -EFAULT; | |
1336 | return ret; | |
1337 | } | |
1338 | ||
1339 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1340 | } | |
19f4fc3a AV |
1341 | |
1342 | #ifdef CONFIG_COMPAT | |
1343 | COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, | |
1344 | compat_off_t __user *, offset, compat_size_t, count) | |
1345 | { | |
1346 | loff_t pos; | |
1347 | off_t off; | |
1348 | ssize_t ret; | |
1349 | ||
1350 | if (offset) { | |
1351 | if (unlikely(get_user(off, offset))) | |
1352 | return -EFAULT; | |
1353 | pos = off; | |
1354 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); | |
1355 | if (unlikely(put_user(pos, offset))) | |
1356 | return -EFAULT; | |
1357 | return ret; | |
1358 | } | |
1359 | ||
1360 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1361 | } | |
1362 | ||
1363 | COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, | |
1364 | compat_loff_t __user *, offset, compat_size_t, count) | |
1365 | { | |
1366 | loff_t pos; | |
1367 | ssize_t ret; | |
1368 | ||
1369 | if (offset) { | |
1370 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) | |
1371 | return -EFAULT; | |
1372 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); | |
1373 | if (unlikely(put_user(pos, offset))) | |
1374 | return -EFAULT; | |
1375 | return ret; | |
1376 | } | |
1377 | ||
1378 | return do_sendfile(out_fd, in_fd, NULL, count, 0); | |
1379 | } | |
1380 | #endif |