blob: 819ef3faf1bb710678175de06a13f4dcf6e90d62 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Robert Love0eeca282005-07-12 17:06:03 -040012#include <linux/fsnotify.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/security.h>
Paul Gortmaker630d9c42011-11-16 23:57:37 -050014#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/syscalls.h>
Linus Torvaldse28cc712006-01-04 16:20:40 -080016#include <linux/pagemap.h>
Jens Axboed6b29d72007-06-04 09:59:47 +020017#include <linux/splice.h>
Al Viro561c6732013-02-24 10:52:26 -050018#include <linux/compat.h>
Al Viro06ae43f2013-03-20 13:19:30 -040019#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
21#include <asm/uaccess.h>
22#include <asm/unistd.h>
23
Al Viroc0bd14af2013-05-04 15:00:54 -040024typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *);
Al Viro293bc982014-02-11 18:37:41 -050025typedef ssize_t (*iter_fn_t)(struct kiocb *, struct iov_iter *);
Al Viroc0bd14af2013-05-04 15:00:54 -040026
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080027const struct file_operations generic_ro_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 .llseek = generic_file_llseek,
Al Viroaad4f8b2014-04-02 14:33:16 -040029 .read_iter = generic_file_read_iter,
Linus Torvalds1da177e2005-04-16 15:20:36 -070030 .mmap = generic_file_readonly_mmap,
Jens Axboe534f2aa2007-06-01 14:52:37 +020031 .splice_read = generic_file_splice_read,
Linus Torvalds1da177e2005-04-16 15:20:36 -070032};
33
34EXPORT_SYMBOL(generic_ro_fops);
35
Al Virocccb5a12010-12-17 07:44:05 -050036static inline int unsigned_offsets(struct file *file)
KAMEZAWA Hiroyuki4a3956c2010-10-01 14:20:22 -070037{
Al Virocccb5a12010-12-17 07:44:05 -050038 return file->f_mode & FMODE_UNSIGNED_OFFSET;
KAMEZAWA Hiroyuki4a3956c2010-10-01 14:20:22 -070039}
40
Jie Liu46a1c2c2013-06-25 12:02:13 +080041/**
42 * vfs_setpos - update the file offset for lseek
43 * @file: file structure in question
44 * @offset: file offset to seek to
45 * @maxsize: maximum file size
46 *
47 * This is a low-level filesystem helper for updating the file offset to
48 * the value specified by @offset if the given offset is valid and it is
49 * not equal to the current file offset.
50 *
51 * Return the specified offset on success and -EINVAL on invalid offset.
52 */
53loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize)
Andi Kleenef3d0fd2011-09-15 16:06:48 -070054{
55 if (offset < 0 && !unsigned_offsets(file))
56 return -EINVAL;
57 if (offset > maxsize)
58 return -EINVAL;
59
60 if (offset != file->f_pos) {
61 file->f_pos = offset;
62 file->f_version = 0;
63 }
64 return offset;
65}
Jie Liu46a1c2c2013-06-25 12:02:13 +080066EXPORT_SYMBOL(vfs_setpos);
Andi Kleenef3d0fd2011-09-15 16:06:48 -070067
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020068/**
Andi Kleen57604952011-09-15 16:06:50 -070069 * generic_file_llseek_size - generic llseek implementation for regular files
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020070 * @file: file structure to seek on
71 * @offset: file offset to seek to
Andrew Morton965c8e52012-12-17 15:59:39 -080072 * @whence: type of seek
Eric Sandeene8b96eb2012-04-30 13:11:29 -050073 * @size: max size of this file in file system
74 * @eof: offset used for SEEK_END position
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020075 *
Andi Kleen57604952011-09-15 16:06:50 -070076 * This is a variant of generic_file_llseek that allows passing in a custom
Eric Sandeene8b96eb2012-04-30 13:11:29 -050077 * maximum file size and a custom EOF position, for e.g. hashed directories
Andi Kleenef3d0fd2011-09-15 16:06:48 -070078 *
79 * Synchronization:
Andi Kleen57604952011-09-15 16:06:50 -070080 * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms)
Andi Kleenef3d0fd2011-09-15 16:06:48 -070081 * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes.
82 * read/writes behave like SEEK_SET against seeks.
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020083 */
Andi Kleen9465efc2008-06-27 11:05:24 +020084loff_t
Andrew Morton965c8e52012-12-17 15:59:39 -080085generic_file_llseek_size(struct file *file, loff_t offset, int whence,
Eric Sandeene8b96eb2012-04-30 13:11:29 -050086 loff_t maxsize, loff_t eof)
Linus Torvalds1da177e2005-04-16 15:20:36 -070087{
Andrew Morton965c8e52012-12-17 15:59:39 -080088 switch (whence) {
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020089 case SEEK_END:
Eric Sandeene8b96eb2012-04-30 13:11:29 -050090 offset += eof;
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020091 break;
92 case SEEK_CUR:
Alain Knaff5b6f1eb2008-11-10 17:08:08 -080093 /*
94 * Here we special-case the lseek(fd, 0, SEEK_CUR)
95 * position-querying operation. Avoid rewriting the "same"
96 * f_pos value back to the file because a concurrent read(),
97 * write() or lseek() might have altered it
98 */
99 if (offset == 0)
100 return file->f_pos;
Andi Kleenef3d0fd2011-09-15 16:06:48 -0700101 /*
102 * f_lock protects against read/modify/write race with other
103 * SEEK_CURs. Note that parallel writes and reads behave
104 * like SEEK_SET.
105 */
106 spin_lock(&file->f_lock);
Jie Liu46a1c2c2013-06-25 12:02:13 +0800107 offset = vfs_setpos(file, file->f_pos + offset, maxsize);
Andi Kleenef3d0fd2011-09-15 16:06:48 -0700108 spin_unlock(&file->f_lock);
109 return offset;
Josef Bacik982d8162011-07-18 13:21:35 -0400110 case SEEK_DATA:
111 /*
112 * In the generic case the entire file is data, so as long as
113 * offset isn't at the end of the file then the offset is data.
114 */
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500115 if (offset >= eof)
Josef Bacik982d8162011-07-18 13:21:35 -0400116 return -ENXIO;
117 break;
118 case SEEK_HOLE:
119 /*
120 * There is a virtual hole at the end of the file, so as long as
121 * offset isn't i_size or larger, return i_size.
122 */
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500123 if (offset >= eof)
Josef Bacik982d8162011-07-18 13:21:35 -0400124 return -ENXIO;
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500125 offset = eof;
Josef Bacik982d8162011-07-18 13:21:35 -0400126 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 }
Christoph Hellwig3a8cff42008-08-11 15:37:17 +0200128
Jie Liu46a1c2c2013-06-25 12:02:13 +0800129 return vfs_setpos(file, offset, maxsize);
Andi Kleen57604952011-09-15 16:06:50 -0700130}
131EXPORT_SYMBOL(generic_file_llseek_size);
132
133/**
134 * generic_file_llseek - generic llseek implementation for regular files
135 * @file: file structure to seek on
136 * @offset: file offset to seek to
Andrew Morton965c8e52012-12-17 15:59:39 -0800137 * @whence: type of seek
Andi Kleen57604952011-09-15 16:06:50 -0700138 *
139 * This is a generic implemenation of ->llseek useable for all normal local
140 * filesystems. It just updates the file offset to the value specified by
Ming Lei546ae2d2013-04-29 15:06:07 -0700141 * @offset and @whence.
Andi Kleen57604952011-09-15 16:06:50 -0700142 */
Andrew Morton965c8e52012-12-17 15:59:39 -0800143loff_t generic_file_llseek(struct file *file, loff_t offset, int whence)
Andi Kleen57604952011-09-15 16:06:50 -0700144{
145 struct inode *inode = file->f_mapping->host;
146
Andrew Morton965c8e52012-12-17 15:59:39 -0800147 return generic_file_llseek_size(file, offset, whence,
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500148 inode->i_sb->s_maxbytes,
149 i_size_read(inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150}
Andi Kleen9465efc2008-06-27 11:05:24 +0200151EXPORT_SYMBOL(generic_file_llseek);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152
jan Blunckae6afc32010-05-26 14:44:48 -0700153/**
Al Viro1bf9d142013-06-16 20:27:42 +0400154 * fixed_size_llseek - llseek implementation for fixed-sized devices
155 * @file: file structure to seek on
156 * @offset: file offset to seek to
157 * @whence: type of seek
158 * @size: size of the file
159 *
160 */
161loff_t fixed_size_llseek(struct file *file, loff_t offset, int whence, loff_t size)
162{
163 switch (whence) {
164 case SEEK_SET: case SEEK_CUR: case SEEK_END:
165 return generic_file_llseek_size(file, offset, whence,
166 size, size);
167 default:
168 return -EINVAL;
169 }
170}
171EXPORT_SYMBOL(fixed_size_llseek);
172
173/**
jan Blunckae6afc32010-05-26 14:44:48 -0700174 * noop_llseek - No Operation Performed llseek implementation
175 * @file: file structure to seek on
176 * @offset: file offset to seek to
Andrew Morton965c8e52012-12-17 15:59:39 -0800177 * @whence: type of seek
jan Blunckae6afc32010-05-26 14:44:48 -0700178 *
179 * This is an implementation of ->llseek useable for the rare special case when
180 * userspace expects the seek to succeed but the (device) file is actually not
181 * able to perform the seek. In this case you use noop_llseek() instead of
182 * falling back to the default implementation of ->llseek.
183 */
Andrew Morton965c8e52012-12-17 15:59:39 -0800184loff_t noop_llseek(struct file *file, loff_t offset, int whence)
jan Blunckae6afc32010-05-26 14:44:48 -0700185{
186 return file->f_pos;
187}
188EXPORT_SYMBOL(noop_llseek);
189
Andrew Morton965c8e52012-12-17 15:59:39 -0800190loff_t no_llseek(struct file *file, loff_t offset, int whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191{
192 return -ESPIPE;
193}
194EXPORT_SYMBOL(no_llseek);
195
Andrew Morton965c8e52012-12-17 15:59:39 -0800196loff_t default_llseek(struct file *file, loff_t offset, int whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197{
Al Viro496ad9a2013-01-23 17:07:38 -0500198 struct inode *inode = file_inode(file);
David Sterba16abef02008-04-22 15:09:22 +0200199 loff_t retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
Josef Bacik982d8162011-07-18 13:21:35 -0400201 mutex_lock(&inode->i_mutex);
Andrew Morton965c8e52012-12-17 15:59:39 -0800202 switch (whence) {
Chris Snook7b8e8922007-05-08 00:24:13 -0700203 case SEEK_END:
Josef Bacik982d8162011-07-18 13:21:35 -0400204 offset += i_size_read(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 break;
Chris Snook7b8e8922007-05-08 00:24:13 -0700206 case SEEK_CUR:
Alain Knaff5b6f1eb2008-11-10 17:08:08 -0800207 if (offset == 0) {
208 retval = file->f_pos;
209 goto out;
210 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 offset += file->f_pos;
Josef Bacik982d8162011-07-18 13:21:35 -0400212 break;
213 case SEEK_DATA:
214 /*
215 * In the generic case the entire file is data, so as
216 * long as offset isn't at the end of the file then the
217 * offset is data.
218 */
Dan Carpenterbacb2d82011-07-26 17:25:20 +0300219 if (offset >= inode->i_size) {
220 retval = -ENXIO;
221 goto out;
222 }
Josef Bacik982d8162011-07-18 13:21:35 -0400223 break;
224 case SEEK_HOLE:
225 /*
226 * There is a virtual hole at the end of the file, so
227 * as long as offset isn't i_size or larger, return
228 * i_size.
229 */
Dan Carpenterbacb2d82011-07-26 17:25:20 +0300230 if (offset >= inode->i_size) {
231 retval = -ENXIO;
232 goto out;
233 }
Josef Bacik982d8162011-07-18 13:21:35 -0400234 offset = inode->i_size;
235 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 }
237 retval = -EINVAL;
Al Virocccb5a12010-12-17 07:44:05 -0500238 if (offset >= 0 || unsigned_offsets(file)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 if (offset != file->f_pos) {
240 file->f_pos = offset;
241 file->f_version = 0;
242 }
243 retval = offset;
244 }
Alain Knaff5b6f1eb2008-11-10 17:08:08 -0800245out:
Josef Bacik982d8162011-07-18 13:21:35 -0400246 mutex_unlock(&inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 return retval;
248}
249EXPORT_SYMBOL(default_llseek);
250
Andrew Morton965c8e52012-12-17 15:59:39 -0800251loff_t vfs_llseek(struct file *file, loff_t offset, int whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252{
253 loff_t (*fn)(struct file *, loff_t, int);
254
255 fn = no_llseek;
256 if (file->f_mode & FMODE_LSEEK) {
Al Viro72c2d532013-09-22 16:27:52 -0400257 if (file->f_op->llseek)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 fn = file->f_op->llseek;
259 }
Andrew Morton965c8e52012-12-17 15:59:39 -0800260 return fn(file, offset, whence);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261}
262EXPORT_SYMBOL(vfs_llseek);
263
Linus Torvalds9c225f22014-03-03 09:36:58 -0800264static inline struct fd fdget_pos(int fd)
265{
Al Virobd2a31d2014-03-04 14:54:22 -0500266 return __to_fd(__fdget_pos(fd));
Linus Torvalds9c225f22014-03-03 09:36:58 -0800267}
268
269static inline void fdput_pos(struct fd f)
270{
271 if (f.flags & FDPUT_POS_UNLOCK)
272 mutex_unlock(&f.file->f_pos_lock);
273 fdput(f);
274}
275
Andrew Morton965c8e52012-12-17 15:59:39 -0800276SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277{
278 off_t retval;
Linus Torvalds9c225f22014-03-03 09:36:58 -0800279 struct fd f = fdget_pos(fd);
Al Viro2903ff02012-08-28 12:52:22 -0400280 if (!f.file)
281 return -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282
283 retval = -EINVAL;
Andrew Morton965c8e52012-12-17 15:59:39 -0800284 if (whence <= SEEK_MAX) {
285 loff_t res = vfs_llseek(f.file, offset, whence);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 retval = res;
287 if (res != (loff_t)retval)
288 retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */
289 }
Linus Torvalds9c225f22014-03-03 09:36:58 -0800290 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 return retval;
292}
293
Al Viro561c6732013-02-24 10:52:26 -0500294#ifdef CONFIG_COMPAT
295COMPAT_SYSCALL_DEFINE3(lseek, unsigned int, fd, compat_off_t, offset, unsigned int, whence)
296{
297 return sys_lseek(fd, offset, whence);
298}
299#endif
300
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301#ifdef __ARCH_WANT_SYS_LLSEEK
Heiko Carstens003d7ab2009-01-14 14:14:21 +0100302SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high,
303 unsigned long, offset_low, loff_t __user *, result,
Andrew Morton965c8e52012-12-17 15:59:39 -0800304 unsigned int, whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305{
306 int retval;
Eric Biggersd7a15f82014-03-16 14:24:08 -0500307 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 loff_t offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309
Al Viro2903ff02012-08-28 12:52:22 -0400310 if (!f.file)
311 return -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312
313 retval = -EINVAL;
Andrew Morton965c8e52012-12-17 15:59:39 -0800314 if (whence > SEEK_MAX)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 goto out_putf;
316
Al Viro2903ff02012-08-28 12:52:22 -0400317 offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low,
Andrew Morton965c8e52012-12-17 15:59:39 -0800318 whence);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319
320 retval = (int)offset;
321 if (offset >= 0) {
322 retval = -EFAULT;
323 if (!copy_to_user(result, &offset, sizeof(offset)))
324 retval = 0;
325 }
326out_putf:
Eric Biggersd7a15f82014-03-16 14:24:08 -0500327 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 return retval;
329}
330#endif
331
Christoph Hellwigdbe4e192015-01-25 21:11:59 +0100332ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos)
333{
334 struct kiocb kiocb;
335 ssize_t ret;
336
337 if (!file->f_op->read_iter)
338 return -EINVAL;
339
340 init_sync_kiocb(&kiocb, file);
341 kiocb.ki_pos = *ppos;
Christoph Hellwigdbe4e192015-01-25 21:11:59 +0100342
343 iter->type |= READ;
344 ret = file->f_op->read_iter(&kiocb, iter);
Christoph Hellwig599bd192015-02-11 19:59:44 +0100345 BUG_ON(ret == -EIOCBQUEUED);
Christoph Hellwigdbe4e192015-01-25 21:11:59 +0100346 if (ret > 0)
347 *ppos = kiocb.ki_pos;
348 return ret;
349}
350EXPORT_SYMBOL(vfs_iter_read);
351
352ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos)
353{
354 struct kiocb kiocb;
355 ssize_t ret;
356
357 if (!file->f_op->write_iter)
358 return -EINVAL;
359
360 init_sync_kiocb(&kiocb, file);
361 kiocb.ki_pos = *ppos;
Christoph Hellwigdbe4e192015-01-25 21:11:59 +0100362
363 iter->type |= WRITE;
364 ret = file->f_op->write_iter(&kiocb, iter);
Christoph Hellwig599bd192015-02-11 19:59:44 +0100365 BUG_ON(ret == -EIOCBQUEUED);
Christoph Hellwigdbe4e192015-01-25 21:11:59 +0100366 if (ret > 0)
367 *ppos = kiocb.ki_pos;
368 return ret;
369}
370EXPORT_SYMBOL(vfs_iter_write);
371
Linus Torvaldse28cc712006-01-04 16:20:40 -0800372/*
373 * rw_verify_area doesn't like huge counts. We limit
374 * them to something that fits in "int" so that others
375 * won't have to do range checks all the time.
376 */
Al Viro68d70d02013-06-19 15:26:04 +0400377int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378{
379 struct inode *inode;
380 loff_t pos;
James Morrisc43e2592008-01-12 22:05:48 +1100381 int retval = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
Al Viro496ad9a2013-01-23 17:07:38 -0500383 inode = file_inode(file);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800384 if (unlikely((ssize_t) count < 0))
James Morrisc43e2592008-01-12 22:05:48 +1100385 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 pos = *ppos;
Al Virocccb5a12010-12-17 07:44:05 -0500387 if (unlikely(pos < 0)) {
388 if (!unsigned_offsets(file))
389 return retval;
390 if (count >= -pos) /* both values are in 0..LLONG_MAX */
391 return -EOVERFLOW;
392 } else if (unlikely((loff_t) (pos + count) < 0)) {
393 if (!unsigned_offsets(file))
KAMEZAWA Hiroyuki4a3956c2010-10-01 14:20:22 -0700394 return retval;
395 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396
Jeff Laytonbd61e0a2015-01-16 15:05:55 -0500397 if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
James Morrisc43e2592008-01-12 22:05:48 +1100398 retval = locks_mandatory_area(
Linus Torvaldse28cc712006-01-04 16:20:40 -0800399 read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE,
400 inode, file, pos, count);
401 if (retval < 0)
402 return retval;
403 }
James Morrisc43e2592008-01-12 22:05:48 +1100404 retval = security_file_permission(file,
405 read_write == READ ? MAY_READ : MAY_WRITE);
406 if (retval)
407 return retval;
Linus Torvaldse28cc712006-01-04 16:20:40 -0800408 return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409}
410
Al Viro5d5d5682015-04-03 15:41:18 -0400411static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
Al Viro293bc982014-02-11 18:37:41 -0500412{
413 struct iovec iov = { .iov_base = buf, .iov_len = len };
414 struct kiocb kiocb;
415 struct iov_iter iter;
416 ssize_t ret;
417
418 init_sync_kiocb(&kiocb, filp);
419 kiocb.ki_pos = *ppos;
Al Viro293bc982014-02-11 18:37:41 -0500420 iov_iter_init(&iter, READ, &iov, 1, len);
421
422 ret = filp->f_op->read_iter(&kiocb, &iter);
Christoph Hellwig599bd192015-02-11 19:59:44 +0100423 BUG_ON(ret == -EIOCBQUEUED);
Al Viro293bc982014-02-11 18:37:41 -0500424 *ppos = kiocb.ki_pos;
425 return ret;
426}
427
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200428ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
429 loff_t *pos)
430{
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200431 if (file->f_op->read)
Al Viro3d04c8a2015-04-03 15:09:18 -0400432 return file->f_op->read(file, buf, count, pos);
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200433 else if (file->f_op->read_iter)
Al Viro3d04c8a2015-04-03 15:09:18 -0400434 return new_sync_read(file, buf, count, pos);
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200435 else
Al Viro3d04c8a2015-04-03 15:09:18 -0400436 return -EINVAL;
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200437}
Al Viro3d04c8a2015-04-03 15:09:18 -0400438EXPORT_SYMBOL(__vfs_read);
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200439
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
441{
442 ssize_t ret;
443
444 if (!(file->f_mode & FMODE_READ))
445 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500446 if (!(file->f_mode & FMODE_CAN_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 return -EINVAL;
448 if (unlikely(!access_ok(VERIFY_WRITE, buf, count)))
449 return -EFAULT;
450
451 ret = rw_verify_area(READ, file, pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800452 if (ret >= 0) {
453 count = ret;
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200454 ret = __vfs_read(file, buf, count, pos);
James Morrisc43e2592008-01-12 22:05:48 +1100455 if (ret > 0) {
Eric Paris2a12a9d2009-12-17 21:24:21 -0500456 fsnotify_access(file);
James Morrisc43e2592008-01-12 22:05:48 +1100457 add_rchar(current, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 }
James Morrisc43e2592008-01-12 22:05:48 +1100459 inc_syscr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 }
461
462 return ret;
463}
464
465EXPORT_SYMBOL(vfs_read);
466
Al Viro5d5d5682015-04-03 15:41:18 -0400467static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
Al Viro293bc982014-02-11 18:37:41 -0500468{
469 struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
470 struct kiocb kiocb;
471 struct iov_iter iter;
472 ssize_t ret;
473
474 init_sync_kiocb(&kiocb, filp);
475 kiocb.ki_pos = *ppos;
Al Viro293bc982014-02-11 18:37:41 -0500476 iov_iter_init(&iter, WRITE, &iov, 1, len);
477
478 ret = filp->f_op->write_iter(&kiocb, &iter);
Christoph Hellwig599bd192015-02-11 19:59:44 +0100479 BUG_ON(ret == -EIOCBQUEUED);
Al Virof765b132015-04-06 20:50:38 -0400480 if (ret > 0)
481 *ppos = kiocb.ki_pos;
Al Viro293bc982014-02-11 18:37:41 -0500482 return ret;
483}
484
Al Viro493c84c2015-04-03 15:06:43 -0400485ssize_t __vfs_write(struct file *file, const char __user *p, size_t count,
486 loff_t *pos)
487{
488 if (file->f_op->write)
489 return file->f_op->write(file, p, count, pos);
Al Viro493c84c2015-04-03 15:06:43 -0400490 else if (file->f_op->write_iter)
491 return new_sync_write(file, p, count, pos);
492 else
493 return -EINVAL;
494}
495EXPORT_SYMBOL(__vfs_write);
496
Al Viro06ae43f2013-03-20 13:19:30 -0400497ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos)
498{
499 mm_segment_t old_fs;
500 const char __user *p;
501 ssize_t ret;
502
Al Viro7f7f25e2014-02-11 17:49:24 -0500503 if (!(file->f_mode & FMODE_CAN_WRITE))
Al Viro3e84f482013-03-27 15:20:30 +0000504 return -EINVAL;
505
Al Viro06ae43f2013-03-20 13:19:30 -0400506 old_fs = get_fs();
507 set_fs(get_ds());
508 p = (__force const char __user *)buf;
509 if (count > MAX_RW_COUNT)
510 count = MAX_RW_COUNT;
Al Viro493c84c2015-04-03 15:06:43 -0400511 ret = __vfs_write(file, p, count, pos);
Al Viro06ae43f2013-03-20 13:19:30 -0400512 set_fs(old_fs);
513 if (ret > 0) {
514 fsnotify_modify(file);
515 add_wchar(current, ret);
516 }
517 inc_syscw(current);
518 return ret;
519}
520
Al Viro2ec3a122014-08-19 11:48:09 -0400521EXPORT_SYMBOL(__kernel_write);
522
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos)
524{
525 ssize_t ret;
526
527 if (!(file->f_mode & FMODE_WRITE))
528 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500529 if (!(file->f_mode & FMODE_CAN_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 return -EINVAL;
531 if (unlikely(!access_ok(VERIFY_READ, buf, count)))
532 return -EFAULT;
533
534 ret = rw_verify_area(WRITE, file, pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800535 if (ret >= 0) {
536 count = ret;
Al Viro03d95eb2013-03-20 13:04:20 -0400537 file_start_write(file);
Al Viro493c84c2015-04-03 15:06:43 -0400538 ret = __vfs_write(file, buf, count, pos);
James Morrisc43e2592008-01-12 22:05:48 +1100539 if (ret > 0) {
Eric Paris2a12a9d2009-12-17 21:24:21 -0500540 fsnotify_modify(file);
James Morrisc43e2592008-01-12 22:05:48 +1100541 add_wchar(current, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 }
James Morrisc43e2592008-01-12 22:05:48 +1100543 inc_syscw(current);
Al Viro03d95eb2013-03-20 13:04:20 -0400544 file_end_write(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 }
546
547 return ret;
548}
549
550EXPORT_SYMBOL(vfs_write);
551
552static inline loff_t file_pos_read(struct file *file)
553{
554 return file->f_pos;
555}
556
557static inline void file_pos_write(struct file *file, loff_t pos)
558{
559 file->f_pos = pos;
560}
561
Heiko Carstens3cdad422009-01-14 14:14:22 +0100562SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800564 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566
Al Viro2903ff02012-08-28 12:52:22 -0400567 if (f.file) {
568 loff_t pos = file_pos_read(f.file);
569 ret = vfs_read(f.file, buf, count, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400570 if (ret >= 0)
571 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800572 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 return ret;
575}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576
Heiko Carstens3cdad422009-01-14 14:14:22 +0100577SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
578 size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800580 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582
Al Viro2903ff02012-08-28 12:52:22 -0400583 if (f.file) {
584 loff_t pos = file_pos_read(f.file);
585 ret = vfs_write(f.file, buf, count, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400586 if (ret >= 0)
587 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800588 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 }
590
591 return ret;
592}
593
Al Viro4a0fd5b2013-01-21 15:16:58 -0500594SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf,
595 size_t, count, loff_t, pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596{
Al Viro2903ff02012-08-28 12:52:22 -0400597 struct fd f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
600 if (pos < 0)
601 return -EINVAL;
602
Al Viro2903ff02012-08-28 12:52:22 -0400603 f = fdget(fd);
604 if (f.file) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400606 if (f.file->f_mode & FMODE_PREAD)
607 ret = vfs_read(f.file, buf, count, &pos);
608 fdput(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 }
610
611 return ret;
612}
613
Al Viro4a0fd5b2013-01-21 15:16:58 -0500614SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf,
615 size_t, count, loff_t, pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616{
Al Viro2903ff02012-08-28 12:52:22 -0400617 struct fd f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619
620 if (pos < 0)
621 return -EINVAL;
622
Al Viro2903ff02012-08-28 12:52:22 -0400623 f = fdget(fd);
624 if (f.file) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400626 if (f.file->f_mode & FMODE_PWRITE)
627 ret = vfs_write(f.file, buf, count, &pos);
628 fdput(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 }
630
631 return ret;
632}
633
634/*
635 * Reduce an iovec's length in-place. Return the resulting number of segments
636 */
637unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to)
638{
639 unsigned long seg = 0;
640 size_t len = 0;
641
642 while (seg < nr_segs) {
643 seg++;
644 if (len + iov->iov_len >= to) {
645 iov->iov_len = to - len;
646 break;
647 }
648 len += iov->iov_len;
649 iov++;
650 }
651 return seg;
652}
Eric Sandeen19295522008-01-28 23:58:27 -0500653EXPORT_SYMBOL(iov_shorten);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654
Al Viroac15ac02015-03-20 20:10:21 -0400655static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter,
656 loff_t *ppos, iter_fn_t fn)
Al Viro293bc982014-02-11 18:37:41 -0500657{
658 struct kiocb kiocb;
Al Viro293bc982014-02-11 18:37:41 -0500659 ssize_t ret;
660
661 init_sync_kiocb(&kiocb, filp);
662 kiocb.ki_pos = *ppos;
Al Viro293bc982014-02-11 18:37:41 -0500663
Al Viroac15ac02015-03-20 20:10:21 -0400664 ret = fn(&kiocb, iter);
Christoph Hellwig599bd192015-02-11 19:59:44 +0100665 BUG_ON(ret == -EIOCBQUEUED);
Al Viro293bc982014-02-11 18:37:41 -0500666 *ppos = kiocb.ki_pos;
667 return ret;
668}
669
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700670/* Do it by hand, with file-ops */
Al Viroac15ac02015-03-20 20:10:21 -0400671static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter,
672 loff_t *ppos, io_fn_t fn)
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700673{
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700674 ssize_t ret = 0;
675
Al Viroac15ac02015-03-20 20:10:21 -0400676 while (iov_iter_count(iter)) {
677 struct iovec iovec = iov_iter_iovec(iter);
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700678 ssize_t nr;
679
Al Viroac15ac02015-03-20 20:10:21 -0400680 nr = fn(filp, iovec.iov_base, iovec.iov_len, ppos);
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700681
682 if (nr < 0) {
683 if (!ret)
684 ret = nr;
685 break;
686 }
687 ret += nr;
Al Viroac15ac02015-03-20 20:10:21 -0400688 if (nr != iovec.iov_len)
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700689 break;
Al Viroac15ac02015-03-20 20:10:21 -0400690 iov_iter_advance(iter, nr);
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700691 }
692
693 return ret;
694}
695
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696/* A write operation does a read from user space and vice versa */
697#define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
698
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700699ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
700 unsigned long nr_segs, unsigned long fast_segs,
701 struct iovec *fast_pointer,
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700702 struct iovec **ret_pointer)
Linus Torvalds435f49a2010-10-29 10:36:49 -0700703{
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700704 unsigned long seg;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700705 ssize_t ret;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700706 struct iovec *iov = fast_pointer;
707
Linus Torvalds435f49a2010-10-29 10:36:49 -0700708 /*
709 * SuS says "The readv() function *may* fail if the iovcnt argument
710 * was less than or equal to 0, or greater than {IOV_MAX}. Linux has
711 * traditionally returned zero for zero segments, so...
712 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700713 if (nr_segs == 0) {
714 ret = 0;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700715 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700716 }
717
Linus Torvalds435f49a2010-10-29 10:36:49 -0700718 /*
719 * First get the "struct iovec" from user memory and
720 * verify all the pointers
721 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700722 if (nr_segs > UIO_MAXIOV) {
723 ret = -EINVAL;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700724 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700725 }
726 if (nr_segs > fast_segs) {
Linus Torvalds435f49a2010-10-29 10:36:49 -0700727 iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700728 if (iov == NULL) {
729 ret = -ENOMEM;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700730 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700731 }
Linus Torvalds435f49a2010-10-29 10:36:49 -0700732 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700733 if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) {
734 ret = -EFAULT;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700735 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700736 }
737
Linus Torvalds435f49a2010-10-29 10:36:49 -0700738 /*
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700739 * According to the Single Unix Specification we should return EINVAL
740 * if an element length is < 0 when cast to ssize_t or if the
741 * total length would overflow the ssize_t return value of the
742 * system call.
Linus Torvalds435f49a2010-10-29 10:36:49 -0700743 *
744 * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the
745 * overflow case.
746 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700747 ret = 0;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700748 for (seg = 0; seg < nr_segs; seg++) {
749 void __user *buf = iov[seg].iov_base;
750 ssize_t len = (ssize_t)iov[seg].iov_len;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700751
752 /* see if we we're about to use an invalid len or if
753 * it's about to overflow ssize_t */
Linus Torvalds435f49a2010-10-29 10:36:49 -0700754 if (len < 0) {
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700755 ret = -EINVAL;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700756 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700757 }
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700758 if (type >= 0
Christopher Yeohfcf63402011-10-31 17:06:39 -0700759 && unlikely(!access_ok(vrfy_dir(type), buf, len))) {
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700760 ret = -EFAULT;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700761 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700762 }
Linus Torvalds435f49a2010-10-29 10:36:49 -0700763 if (len > MAX_RW_COUNT - ret) {
764 len = MAX_RW_COUNT - ret;
765 iov[seg].iov_len = len;
766 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700767 ret += len;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700768 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700769out:
770 *ret_pointer = iov;
771 return ret;
772}
773
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774static ssize_t do_readv_writev(int type, struct file *file,
775 const struct iovec __user * uvector,
776 unsigned long nr_segs, loff_t *pos)
777{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778 size_t tot_len;
779 struct iovec iovstack[UIO_FASTIOV];
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700780 struct iovec *iov = iovstack;
Al Viroac15ac02015-03-20 20:10:21 -0400781 struct iov_iter iter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782 ssize_t ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 io_fn_t fn;
Al Viro293bc982014-02-11 18:37:41 -0500784 iter_fn_t iter_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785
Al Viro0504c072015-03-21 19:40:11 -0400786 ret = import_iovec(type, uvector, nr_segs,
787 ARRAY_SIZE(iovstack), &iov, &iter);
788 if (ret < 0)
789 return ret;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700790
Al Viro0504c072015-03-21 19:40:11 -0400791 tot_len = iov_iter_count(&iter);
792 if (!tot_len)
793 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 ret = rw_verify_area(type, file, pos, tot_len);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800795 if (ret < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 goto out;
797
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 if (type == READ) {
799 fn = file->f_op->read;
Al Viro293bc982014-02-11 18:37:41 -0500800 iter_fn = file->f_op->read_iter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801 } else {
802 fn = (io_fn_t)file->f_op->write;
Al Viro293bc982014-02-11 18:37:41 -0500803 iter_fn = file->f_op->write_iter;
Al Viro03d95eb2013-03-20 13:04:20 -0400804 file_start_write(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 }
806
Al Viro293bc982014-02-11 18:37:41 -0500807 if (iter_fn)
Al Viroac15ac02015-03-20 20:10:21 -0400808 ret = do_iter_readv_writev(file, &iter, pos, iter_fn);
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700809 else
Al Viroac15ac02015-03-20 20:10:21 -0400810 ret = do_loop_readv_writev(file, &iter, pos, fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811
Al Viro03d95eb2013-03-20 13:04:20 -0400812 if (type != READ)
813 file_end_write(file);
814
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815out:
Al Viro0504c072015-03-21 19:40:11 -0400816 kfree(iov);
Robert Love0eeca282005-07-12 17:06:03 -0400817 if ((ret + (type == READ)) > 0) {
818 if (type == READ)
Eric Paris2a12a9d2009-12-17 21:24:21 -0500819 fsnotify_access(file);
Robert Love0eeca282005-07-12 17:06:03 -0400820 else
Eric Paris2a12a9d2009-12-17 21:24:21 -0500821 fsnotify_modify(file);
Robert Love0eeca282005-07-12 17:06:03 -0400822 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700823 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824}
825
826ssize_t vfs_readv(struct file *file, const struct iovec __user *vec,
827 unsigned long vlen, loff_t *pos)
828{
829 if (!(file->f_mode & FMODE_READ))
830 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500831 if (!(file->f_mode & FMODE_CAN_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832 return -EINVAL;
833
834 return do_readv_writev(READ, file, vec, vlen, pos);
835}
836
837EXPORT_SYMBOL(vfs_readv);
838
839ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
840 unsigned long vlen, loff_t *pos)
841{
842 if (!(file->f_mode & FMODE_WRITE))
843 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500844 if (!(file->f_mode & FMODE_CAN_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 return -EINVAL;
846
847 return do_readv_writev(WRITE, file, vec, vlen, pos);
848}
849
850EXPORT_SYMBOL(vfs_writev);
851
Heiko Carstens3cdad422009-01-14 14:14:22 +0100852SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec,
853 unsigned long, vlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800855 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857
Al Viro2903ff02012-08-28 12:52:22 -0400858 if (f.file) {
859 loff_t pos = file_pos_read(f.file);
860 ret = vfs_readv(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400861 if (ret >= 0)
862 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800863 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864 }
865
866 if (ret > 0)
Alexey Dobriyan4b98d112007-02-10 01:46:45 -0800867 add_rchar(current, ret);
868 inc_syscr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869 return ret;
870}
871
Heiko Carstens3cdad422009-01-14 14:14:22 +0100872SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
873 unsigned long, vlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800875 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877
Al Viro2903ff02012-08-28 12:52:22 -0400878 if (f.file) {
879 loff_t pos = file_pos_read(f.file);
880 ret = vfs_writev(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400881 if (ret >= 0)
882 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800883 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 }
885
886 if (ret > 0)
Alexey Dobriyan4b98d112007-02-10 01:46:45 -0800887 add_wchar(current, ret);
888 inc_syscw(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 return ret;
890}
891
Linus Torvalds601cc112009-04-03 08:03:22 -0700892static inline loff_t pos_from_hilo(unsigned long high, unsigned long low)
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700893{
Linus Torvalds601cc112009-04-03 08:03:22 -0700894#define HALF_LONG_BITS (BITS_PER_LONG / 2)
895 return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low;
896}
897
898SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec,
899 unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
900{
901 loff_t pos = pos_from_hilo(pos_h, pos_l);
Al Viro2903ff02012-08-28 12:52:22 -0400902 struct fd f;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700903 ssize_t ret = -EBADF;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700904
905 if (pos < 0)
906 return -EINVAL;
907
Al Viro2903ff02012-08-28 12:52:22 -0400908 f = fdget(fd);
909 if (f.file) {
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700910 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400911 if (f.file->f_mode & FMODE_PREAD)
912 ret = vfs_readv(f.file, vec, vlen, &pos);
913 fdput(f);
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700914 }
915
916 if (ret > 0)
917 add_rchar(current, ret);
918 inc_syscr(current);
919 return ret;
920}
921
922SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec,
Linus Torvalds601cc112009-04-03 08:03:22 -0700923 unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700924{
Linus Torvalds601cc112009-04-03 08:03:22 -0700925 loff_t pos = pos_from_hilo(pos_h, pos_l);
Al Viro2903ff02012-08-28 12:52:22 -0400926 struct fd f;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700927 ssize_t ret = -EBADF;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700928
929 if (pos < 0)
930 return -EINVAL;
931
Al Viro2903ff02012-08-28 12:52:22 -0400932 f = fdget(fd);
933 if (f.file) {
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700934 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400935 if (f.file->f_mode & FMODE_PWRITE)
936 ret = vfs_writev(f.file, vec, vlen, &pos);
937 fdput(f);
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700938 }
939
940 if (ret > 0)
941 add_wchar(current, ret);
942 inc_syscw(current);
943 return ret;
944}
945
Al Viro72ec3512013-03-20 10:42:10 -0400946#ifdef CONFIG_COMPAT
947
948static ssize_t compat_do_readv_writev(int type, struct file *file,
949 const struct compat_iovec __user *uvector,
950 unsigned long nr_segs, loff_t *pos)
951{
952 compat_ssize_t tot_len;
953 struct iovec iovstack[UIO_FASTIOV];
954 struct iovec *iov = iovstack;
Al Viroac15ac02015-03-20 20:10:21 -0400955 struct iov_iter iter;
Al Viro72ec3512013-03-20 10:42:10 -0400956 ssize_t ret;
957 io_fn_t fn;
Al Viro293bc982014-02-11 18:37:41 -0500958 iter_fn_t iter_fn;
Al Viro72ec3512013-03-20 10:42:10 -0400959
Al Viro0504c072015-03-21 19:40:11 -0400960 ret = compat_import_iovec(type, uvector, nr_segs,
961 UIO_FASTIOV, &iov, &iter);
962 if (ret < 0)
963 return ret;
Al Viro72ec3512013-03-20 10:42:10 -0400964
Al Viro0504c072015-03-21 19:40:11 -0400965 tot_len = iov_iter_count(&iter);
966 if (!tot_len)
967 goto out;
Al Viro72ec3512013-03-20 10:42:10 -0400968 ret = rw_verify_area(type, file, pos, tot_len);
969 if (ret < 0)
970 goto out;
971
Al Viro72ec3512013-03-20 10:42:10 -0400972 if (type == READ) {
973 fn = file->f_op->read;
Al Viro293bc982014-02-11 18:37:41 -0500974 iter_fn = file->f_op->read_iter;
Al Viro72ec3512013-03-20 10:42:10 -0400975 } else {
976 fn = (io_fn_t)file->f_op->write;
Al Viro293bc982014-02-11 18:37:41 -0500977 iter_fn = file->f_op->write_iter;
Al Viro03d95eb2013-03-20 13:04:20 -0400978 file_start_write(file);
Al Viro72ec3512013-03-20 10:42:10 -0400979 }
980
Al Viro293bc982014-02-11 18:37:41 -0500981 if (iter_fn)
Al Viroac15ac02015-03-20 20:10:21 -0400982 ret = do_iter_readv_writev(file, &iter, pos, iter_fn);
Al Viro03d95eb2013-03-20 13:04:20 -0400983 else
Al Viroac15ac02015-03-20 20:10:21 -0400984 ret = do_loop_readv_writev(file, &iter, pos, fn);
Al Viro72ec3512013-03-20 10:42:10 -0400985
Al Viro03d95eb2013-03-20 13:04:20 -0400986 if (type != READ)
987 file_end_write(file);
988
Al Viro72ec3512013-03-20 10:42:10 -0400989out:
Al Viro0504c072015-03-21 19:40:11 -0400990 kfree(iov);
Al Viro72ec3512013-03-20 10:42:10 -0400991 if ((ret + (type == READ)) > 0) {
992 if (type == READ)
993 fsnotify_access(file);
994 else
995 fsnotify_modify(file);
996 }
997 return ret;
998}
999
1000static size_t compat_readv(struct file *file,
1001 const struct compat_iovec __user *vec,
1002 unsigned long vlen, loff_t *pos)
1003{
1004 ssize_t ret = -EBADF;
1005
1006 if (!(file->f_mode & FMODE_READ))
1007 goto out;
1008
1009 ret = -EINVAL;
Al Viro7f7f25e2014-02-11 17:49:24 -05001010 if (!(file->f_mode & FMODE_CAN_READ))
Al Viro72ec3512013-03-20 10:42:10 -04001011 goto out;
1012
1013 ret = compat_do_readv_writev(READ, file, vec, vlen, pos);
1014
1015out:
1016 if (ret > 0)
1017 add_rchar(current, ret);
1018 inc_syscr(current);
1019 return ret;
1020}
1021
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001022COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001023 const struct compat_iovec __user *,vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001024 compat_ulong_t, vlen)
Al Viro72ec3512013-03-20 10:42:10 -04001025{
Linus Torvalds9c225f22014-03-03 09:36:58 -08001026 struct fd f = fdget_pos(fd);
Al Viro72ec3512013-03-20 10:42:10 -04001027 ssize_t ret;
1028 loff_t pos;
1029
1030 if (!f.file)
1031 return -EBADF;
1032 pos = f.file->f_pos;
1033 ret = compat_readv(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +04001034 if (ret >= 0)
1035 f.file->f_pos = pos;
Linus Torvalds9c225f22014-03-03 09:36:58 -08001036 fdput_pos(f);
Al Viro72ec3512013-03-20 10:42:10 -04001037 return ret;
1038}
1039
Heiko Carstens378a10f2014-03-05 10:43:51 +01001040static long __compat_sys_preadv64(unsigned long fd,
1041 const struct compat_iovec __user *vec,
1042 unsigned long vlen, loff_t pos)
Al Viro72ec3512013-03-20 10:42:10 -04001043{
1044 struct fd f;
1045 ssize_t ret;
1046
1047 if (pos < 0)
1048 return -EINVAL;
1049 f = fdget(fd);
1050 if (!f.file)
1051 return -EBADF;
1052 ret = -ESPIPE;
1053 if (f.file->f_mode & FMODE_PREAD)
1054 ret = compat_readv(f.file, vec, vlen, &pos);
1055 fdput(f);
1056 return ret;
1057}
1058
Heiko Carstens378a10f2014-03-05 10:43:51 +01001059#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64
1060COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd,
1061 const struct compat_iovec __user *,vec,
1062 unsigned long, vlen, loff_t, pos)
1063{
1064 return __compat_sys_preadv64(fd, vec, vlen, pos);
1065}
1066#endif
1067
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001068COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001069 const struct compat_iovec __user *,vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001070 compat_ulong_t, vlen, u32, pos_low, u32, pos_high)
Al Viro72ec3512013-03-20 10:42:10 -04001071{
1072 loff_t pos = ((loff_t)pos_high << 32) | pos_low;
Heiko Carstens378a10f2014-03-05 10:43:51 +01001073
1074 return __compat_sys_preadv64(fd, vec, vlen, pos);
Al Viro72ec3512013-03-20 10:42:10 -04001075}
1076
1077static size_t compat_writev(struct file *file,
1078 const struct compat_iovec __user *vec,
1079 unsigned long vlen, loff_t *pos)
1080{
1081 ssize_t ret = -EBADF;
1082
1083 if (!(file->f_mode & FMODE_WRITE))
1084 goto out;
1085
1086 ret = -EINVAL;
Al Viro7f7f25e2014-02-11 17:49:24 -05001087 if (!(file->f_mode & FMODE_CAN_WRITE))
Al Viro72ec3512013-03-20 10:42:10 -04001088 goto out;
1089
1090 ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos);
1091
1092out:
1093 if (ret > 0)
1094 add_wchar(current, ret);
1095 inc_syscw(current);
1096 return ret;
1097}
1098
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001099COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001100 const struct compat_iovec __user *, vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001101 compat_ulong_t, vlen)
Al Viro72ec3512013-03-20 10:42:10 -04001102{
Linus Torvalds9c225f22014-03-03 09:36:58 -08001103 struct fd f = fdget_pos(fd);
Al Viro72ec3512013-03-20 10:42:10 -04001104 ssize_t ret;
1105 loff_t pos;
1106
1107 if (!f.file)
1108 return -EBADF;
1109 pos = f.file->f_pos;
1110 ret = compat_writev(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +04001111 if (ret >= 0)
1112 f.file->f_pos = pos;
Linus Torvalds9c225f22014-03-03 09:36:58 -08001113 fdput_pos(f);
Al Viro72ec3512013-03-20 10:42:10 -04001114 return ret;
1115}
1116
Heiko Carstens378a10f2014-03-05 10:43:51 +01001117static long __compat_sys_pwritev64(unsigned long fd,
1118 const struct compat_iovec __user *vec,
1119 unsigned long vlen, loff_t pos)
Al Viro72ec3512013-03-20 10:42:10 -04001120{
1121 struct fd f;
1122 ssize_t ret;
1123
1124 if (pos < 0)
1125 return -EINVAL;
1126 f = fdget(fd);
1127 if (!f.file)
1128 return -EBADF;
1129 ret = -ESPIPE;
1130 if (f.file->f_mode & FMODE_PWRITE)
1131 ret = compat_writev(f.file, vec, vlen, &pos);
1132 fdput(f);
1133 return ret;
1134}
1135
Heiko Carstens378a10f2014-03-05 10:43:51 +01001136#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64
1137COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd,
1138 const struct compat_iovec __user *,vec,
1139 unsigned long, vlen, loff_t, pos)
1140{
1141 return __compat_sys_pwritev64(fd, vec, vlen, pos);
1142}
1143#endif
1144
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001145COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001146 const struct compat_iovec __user *,vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001147 compat_ulong_t, vlen, u32, pos_low, u32, pos_high)
Al Viro72ec3512013-03-20 10:42:10 -04001148{
1149 loff_t pos = ((loff_t)pos_high << 32) | pos_low;
Heiko Carstens378a10f2014-03-05 10:43:51 +01001150
1151 return __compat_sys_pwritev64(fd, vec, vlen, pos);
Al Viro72ec3512013-03-20 10:42:10 -04001152}
1153#endif
1154
Al Viro19f4fc32013-02-24 02:17:03 -05001155static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
1156 size_t count, loff_t max)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001157{
Al Viro2903ff02012-08-28 12:52:22 -04001158 struct fd in, out;
1159 struct inode *in_inode, *out_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160 loff_t pos;
Al Viro7995bd22013-06-20 18:58:36 +04001161 loff_t out_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162 ssize_t retval;
Al Viro2903ff02012-08-28 12:52:22 -04001163 int fl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001164
1165 /*
1166 * Get input file, and verify that it is ok..
1167 */
1168 retval = -EBADF;
Al Viro2903ff02012-08-28 12:52:22 -04001169 in = fdget(in_fd);
1170 if (!in.file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001171 goto out;
Al Viro2903ff02012-08-28 12:52:22 -04001172 if (!(in.file->f_mode & FMODE_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173 goto fput_in;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174 retval = -ESPIPE;
Al Viro7995bd22013-06-20 18:58:36 +04001175 if (!ppos) {
1176 pos = in.file->f_pos;
1177 } else {
1178 pos = *ppos;
Al Viro2903ff02012-08-28 12:52:22 -04001179 if (!(in.file->f_mode & FMODE_PREAD))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 goto fput_in;
Al Viro7995bd22013-06-20 18:58:36 +04001181 }
1182 retval = rw_verify_area(READ, in.file, &pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -08001183 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001184 goto fput_in;
Linus Torvaldse28cc712006-01-04 16:20:40 -08001185 count = retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187 /*
1188 * Get output file, and verify that it is ok..
1189 */
1190 retval = -EBADF;
Al Viro2903ff02012-08-28 12:52:22 -04001191 out = fdget(out_fd);
1192 if (!out.file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001193 goto fput_in;
Al Viro2903ff02012-08-28 12:52:22 -04001194 if (!(out.file->f_mode & FMODE_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001195 goto fput_out;
1196 retval = -EINVAL;
Al Viro496ad9a2013-01-23 17:07:38 -05001197 in_inode = file_inode(in.file);
1198 out_inode = file_inode(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001199 out_pos = out.file->f_pos;
1200 retval = rw_verify_area(WRITE, out.file, &out_pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -08001201 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001202 goto fput_out;
Linus Torvaldse28cc712006-01-04 16:20:40 -08001203 count = retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204
Linus Torvalds1da177e2005-04-16 15:20:36 -07001205 if (!max)
1206 max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
1207
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208 if (unlikely(pos + count > max)) {
1209 retval = -EOVERFLOW;
1210 if (pos >= max)
1211 goto fput_out;
1212 count = max - pos;
1213 }
1214
Jens Axboed96e6e72007-06-11 12:18:52 +02001215 fl = 0;
Jens Axboe534f2aa2007-06-01 14:52:37 +02001216#if 0
Jens Axboed96e6e72007-06-11 12:18:52 +02001217 /*
1218 * We need to debate whether we can enable this or not. The
1219 * man page documents EAGAIN return for the output at least,
1220 * and the application is arguably buggy if it doesn't expect
1221 * EAGAIN on a non-blocking file descriptor.
1222 */
Al Viro2903ff02012-08-28 12:52:22 -04001223 if (in.file->f_flags & O_NONBLOCK)
Jens Axboed96e6e72007-06-11 12:18:52 +02001224 fl = SPLICE_F_NONBLOCK;
Jens Axboe534f2aa2007-06-01 14:52:37 +02001225#endif
Al Viro50cd2c52013-05-23 20:10:34 -04001226 file_start_write(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001227 retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl);
Al Viro50cd2c52013-05-23 20:10:34 -04001228 file_end_write(out.file);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001229
1230 if (retval > 0) {
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001231 add_rchar(current, retval);
1232 add_wchar(current, retval);
Scott Wolchoka68c2f12012-12-20 15:05:52 -08001233 fsnotify_access(in.file);
1234 fsnotify_modify(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001235 out.file->f_pos = out_pos;
1236 if (ppos)
1237 *ppos = pos;
1238 else
1239 in.file->f_pos = pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001240 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001242 inc_syscr(current);
1243 inc_syscw(current);
Al Viro7995bd22013-06-20 18:58:36 +04001244 if (pos > max)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001245 retval = -EOVERFLOW;
1246
1247fput_out:
Al Viro2903ff02012-08-28 12:52:22 -04001248 fdput(out);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001249fput_in:
Al Viro2903ff02012-08-28 12:52:22 -04001250 fdput(in);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001251out:
1252 return retval;
1253}
1254
Heiko Carstens002c8972009-01-14 14:14:18 +01001255SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256{
1257 loff_t pos;
1258 off_t off;
1259 ssize_t ret;
1260
1261 if (offset) {
1262 if (unlikely(get_user(off, offset)))
1263 return -EFAULT;
1264 pos = off;
1265 ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
1266 if (unlikely(put_user(pos, offset)))
1267 return -EFAULT;
1268 return ret;
1269 }
1270
1271 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1272}
1273
Heiko Carstens002c8972009-01-14 14:14:18 +01001274SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275{
1276 loff_t pos;
1277 ssize_t ret;
1278
1279 if (offset) {
1280 if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
1281 return -EFAULT;
1282 ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
1283 if (unlikely(put_user(pos, offset)))
1284 return -EFAULT;
1285 return ret;
1286 }
1287
1288 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1289}
Al Viro19f4fc32013-02-24 02:17:03 -05001290
1291#ifdef CONFIG_COMPAT
1292COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd,
1293 compat_off_t __user *, offset, compat_size_t, count)
1294{
1295 loff_t pos;
1296 off_t off;
1297 ssize_t ret;
1298
1299 if (offset) {
1300 if (unlikely(get_user(off, offset)))
1301 return -EFAULT;
1302 pos = off;
1303 ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
1304 if (unlikely(put_user(pos, offset)))
1305 return -EFAULT;
1306 return ret;
1307 }
1308
1309 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1310}
1311
1312COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd,
1313 compat_loff_t __user *, offset, compat_size_t, count)
1314{
1315 loff_t pos;
1316 ssize_t ret;
1317
1318 if (offset) {
1319 if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
1320 return -EFAULT;
1321 ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
1322 if (unlikely(put_user(pos, offset)))
1323 return -EFAULT;
1324 return ret;
1325 }
1326
1327 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1328}
1329#endif