blob: 8e1b68786d663d4be5551efcd7b0bf7d5ed8b192 [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>
Kent Overstreeta27bb332013-05-07 16:19:08 -070012#include <linux/aio.h>
Robert Love0eeca282005-07-12 17:06:03 -040013#include <linux/fsnotify.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/security.h>
Paul Gortmaker630d9c42011-11-16 23:57:37 -050015#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/syscalls.h>
Linus Torvaldse28cc712006-01-04 16:20:40 -080017#include <linux/pagemap.h>
Jens Axboed6b29d72007-06-04 09:59:47 +020018#include <linux/splice.h>
Al Viro561c6732013-02-24 10:52:26 -050019#include <linux/compat.h>
Al Viro06ae43f2013-03-20 13:19:30 -040020#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070021
22#include <asm/uaccess.h>
23#include <asm/unistd.h>
24
Al Viroc0bd14af2013-05-04 15:00:54 -040025typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *);
26typedef ssize_t (*iov_fn_t)(struct kiocb *, const struct iovec *,
27 unsigned long, loff_t);
Al Viro293bc982014-02-11 18:37:41 -050028typedef ssize_t (*iter_fn_t)(struct kiocb *, struct iov_iter *);
Al Viroc0bd14af2013-05-04 15:00:54 -040029
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080030const struct file_operations generic_ro_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 .llseek = generic_file_llseek,
Al Viroaad4f8b2014-04-02 14:33:16 -040032 .read = new_sync_read,
33 .read_iter = generic_file_read_iter,
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 .mmap = generic_file_readonly_mmap,
Jens Axboe534f2aa2007-06-01 14:52:37 +020035 .splice_read = generic_file_splice_read,
Linus Torvalds1da177e2005-04-16 15:20:36 -070036};
37
38EXPORT_SYMBOL(generic_ro_fops);
39
Al Virocccb5a12010-12-17 07:44:05 -050040static inline int unsigned_offsets(struct file *file)
KAMEZAWA Hiroyuki4a3956c2010-10-01 14:20:22 -070041{
Al Virocccb5a12010-12-17 07:44:05 -050042 return file->f_mode & FMODE_UNSIGNED_OFFSET;
KAMEZAWA Hiroyuki4a3956c2010-10-01 14:20:22 -070043}
44
Jie Liu46a1c2c2013-06-25 12:02:13 +080045/**
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 */
57loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize)
Andi Kleenef3d0fd2011-09-15 16:06:48 -070058{
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}
Jie Liu46a1c2c2013-06-25 12:02:13 +080070EXPORT_SYMBOL(vfs_setpos);
Andi Kleenef3d0fd2011-09-15 16:06:48 -070071
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020072/**
Andi Kleen57604952011-09-15 16:06:50 -070073 * generic_file_llseek_size - generic llseek implementation for regular files
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020074 * @file: file structure to seek on
75 * @offset: file offset to seek to
Andrew Morton965c8e52012-12-17 15:59:39 -080076 * @whence: type of seek
Eric Sandeene8b96eb2012-04-30 13:11:29 -050077 * @size: max size of this file in file system
78 * @eof: offset used for SEEK_END position
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020079 *
Andi Kleen57604952011-09-15 16:06:50 -070080 * This is a variant of generic_file_llseek that allows passing in a custom
Eric Sandeene8b96eb2012-04-30 13:11:29 -050081 * maximum file size and a custom EOF position, for e.g. hashed directories
Andi Kleenef3d0fd2011-09-15 16:06:48 -070082 *
83 * Synchronization:
Andi Kleen57604952011-09-15 16:06:50 -070084 * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms)
Andi Kleenef3d0fd2011-09-15 16:06:48 -070085 * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes.
86 * read/writes behave like SEEK_SET against seeks.
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020087 */
Andi Kleen9465efc2008-06-27 11:05:24 +020088loff_t
Andrew Morton965c8e52012-12-17 15:59:39 -080089generic_file_llseek_size(struct file *file, loff_t offset, int whence,
Eric Sandeene8b96eb2012-04-30 13:11:29 -050090 loff_t maxsize, loff_t eof)
Linus Torvalds1da177e2005-04-16 15:20:36 -070091{
Andrew Morton965c8e52012-12-17 15:59:39 -080092 switch (whence) {
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020093 case SEEK_END:
Eric Sandeene8b96eb2012-04-30 13:11:29 -050094 offset += eof;
Christoph Hellwig3a8cff42008-08-11 15:37:17 +020095 break;
96 case SEEK_CUR:
Alain Knaff5b6f1eb2008-11-10 17:08:08 -080097 /*
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;
Andi Kleenef3d0fd2011-09-15 16:06:48 -0700105 /*
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);
Jie Liu46a1c2c2013-06-25 12:02:13 +0800111 offset = vfs_setpos(file, file->f_pos + offset, maxsize);
Andi Kleenef3d0fd2011-09-15 16:06:48 -0700112 spin_unlock(&file->f_lock);
113 return offset;
Josef Bacik982d8162011-07-18 13:21:35 -0400114 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 */
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500119 if (offset >= eof)
Josef Bacik982d8162011-07-18 13:21:35 -0400120 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 */
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500127 if (offset >= eof)
Josef Bacik982d8162011-07-18 13:21:35 -0400128 return -ENXIO;
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500129 offset = eof;
Josef Bacik982d8162011-07-18 13:21:35 -0400130 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 }
Christoph Hellwig3a8cff42008-08-11 15:37:17 +0200132
Jie Liu46a1c2c2013-06-25 12:02:13 +0800133 return vfs_setpos(file, offset, maxsize);
Andi Kleen57604952011-09-15 16:06:50 -0700134}
135EXPORT_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
Andrew Morton965c8e52012-12-17 15:59:39 -0800141 * @whence: type of seek
Andi Kleen57604952011-09-15 16:06:50 -0700142 *
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
Ming Lei546ae2d2013-04-29 15:06:07 -0700145 * @offset and @whence.
Andi Kleen57604952011-09-15 16:06:50 -0700146 */
Andrew Morton965c8e52012-12-17 15:59:39 -0800147loff_t generic_file_llseek(struct file *file, loff_t offset, int whence)
Andi Kleen57604952011-09-15 16:06:50 -0700148{
149 struct inode *inode = file->f_mapping->host;
150
Andrew Morton965c8e52012-12-17 15:59:39 -0800151 return generic_file_llseek_size(file, offset, whence,
Eric Sandeene8b96eb2012-04-30 13:11:29 -0500152 inode->i_sb->s_maxbytes,
153 i_size_read(inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154}
Andi Kleen9465efc2008-06-27 11:05:24 +0200155EXPORT_SYMBOL(generic_file_llseek);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
jan Blunckae6afc32010-05-26 14:44:48 -0700157/**
Al Viro1bf9d142013-06-16 20:27:42 +0400158 * 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 */
165loff_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}
175EXPORT_SYMBOL(fixed_size_llseek);
176
177/**
jan Blunckae6afc32010-05-26 14:44:48 -0700178 * noop_llseek - No Operation Performed llseek implementation
179 * @file: file structure to seek on
180 * @offset: file offset to seek to
Andrew Morton965c8e52012-12-17 15:59:39 -0800181 * @whence: type of seek
jan Blunckae6afc32010-05-26 14:44:48 -0700182 *
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 */
Andrew Morton965c8e52012-12-17 15:59:39 -0800188loff_t noop_llseek(struct file *file, loff_t offset, int whence)
jan Blunckae6afc32010-05-26 14:44:48 -0700189{
190 return file->f_pos;
191}
192EXPORT_SYMBOL(noop_llseek);
193
Andrew Morton965c8e52012-12-17 15:59:39 -0800194loff_t no_llseek(struct file *file, loff_t offset, int whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195{
196 return -ESPIPE;
197}
198EXPORT_SYMBOL(no_llseek);
199
Andrew Morton965c8e52012-12-17 15:59:39 -0800200loff_t default_llseek(struct file *file, loff_t offset, int whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201{
Al Viro496ad9a2013-01-23 17:07:38 -0500202 struct inode *inode = file_inode(file);
David Sterba16abef02008-04-22 15:09:22 +0200203 loff_t retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
Josef Bacik982d8162011-07-18 13:21:35 -0400205 mutex_lock(&inode->i_mutex);
Andrew Morton965c8e52012-12-17 15:59:39 -0800206 switch (whence) {
Chris Snook7b8e8922007-05-08 00:24:13 -0700207 case SEEK_END:
Josef Bacik982d8162011-07-18 13:21:35 -0400208 offset += i_size_read(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 break;
Chris Snook7b8e8922007-05-08 00:24:13 -0700210 case SEEK_CUR:
Alain Knaff5b6f1eb2008-11-10 17:08:08 -0800211 if (offset == 0) {
212 retval = file->f_pos;
213 goto out;
214 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 offset += file->f_pos;
Josef Bacik982d8162011-07-18 13:21:35 -0400216 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 */
Dan Carpenterbacb2d82011-07-26 17:25:20 +0300223 if (offset >= inode->i_size) {
224 retval = -ENXIO;
225 goto out;
226 }
Josef Bacik982d8162011-07-18 13:21:35 -0400227 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 */
Dan Carpenterbacb2d82011-07-26 17:25:20 +0300234 if (offset >= inode->i_size) {
235 retval = -ENXIO;
236 goto out;
237 }
Josef Bacik982d8162011-07-18 13:21:35 -0400238 offset = inode->i_size;
239 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 }
241 retval = -EINVAL;
Al Virocccb5a12010-12-17 07:44:05 -0500242 if (offset >= 0 || unsigned_offsets(file)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 if (offset != file->f_pos) {
244 file->f_pos = offset;
245 file->f_version = 0;
246 }
247 retval = offset;
248 }
Alain Knaff5b6f1eb2008-11-10 17:08:08 -0800249out:
Josef Bacik982d8162011-07-18 13:21:35 -0400250 mutex_unlock(&inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 return retval;
252}
253EXPORT_SYMBOL(default_llseek);
254
Andrew Morton965c8e52012-12-17 15:59:39 -0800255loff_t vfs_llseek(struct file *file, loff_t offset, int whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256{
257 loff_t (*fn)(struct file *, loff_t, int);
258
259 fn = no_llseek;
260 if (file->f_mode & FMODE_LSEEK) {
Al Viro72c2d532013-09-22 16:27:52 -0400261 if (file->f_op->llseek)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 fn = file->f_op->llseek;
263 }
Andrew Morton965c8e52012-12-17 15:59:39 -0800264 return fn(file, offset, whence);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265}
266EXPORT_SYMBOL(vfs_llseek);
267
Linus Torvalds9c225f22014-03-03 09:36:58 -0800268static inline struct fd fdget_pos(int fd)
269{
Al Virobd2a31d2014-03-04 14:54:22 -0500270 return __to_fd(__fdget_pos(fd));
Linus Torvalds9c225f22014-03-03 09:36:58 -0800271}
272
273static 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
Andrew Morton965c8e52012-12-17 15:59:39 -0800280SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281{
282 off_t retval;
Linus Torvalds9c225f22014-03-03 09:36:58 -0800283 struct fd f = fdget_pos(fd);
Al Viro2903ff02012-08-28 12:52:22 -0400284 if (!f.file)
285 return -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286
287 retval = -EINVAL;
Andrew Morton965c8e52012-12-17 15:59:39 -0800288 if (whence <= SEEK_MAX) {
289 loff_t res = vfs_llseek(f.file, offset, whence);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 retval = res;
291 if (res != (loff_t)retval)
292 retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */
293 }
Linus Torvalds9c225f22014-03-03 09:36:58 -0800294 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 return retval;
296}
297
Al Viro561c6732013-02-24 10:52:26 -0500298#ifdef CONFIG_COMPAT
299COMPAT_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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305#ifdef __ARCH_WANT_SYS_LLSEEK
Heiko Carstens003d7ab2009-01-14 14:14:21 +0100306SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high,
307 unsigned long, offset_low, loff_t __user *, result,
Andrew Morton965c8e52012-12-17 15:59:39 -0800308 unsigned int, whence)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309{
310 int retval;
Eric Biggersd7a15f82014-03-16 14:24:08 -0500311 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 loff_t offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313
Al Viro2903ff02012-08-28 12:52:22 -0400314 if (!f.file)
315 return -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316
317 retval = -EINVAL;
Andrew Morton965c8e52012-12-17 15:59:39 -0800318 if (whence > SEEK_MAX)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 goto out_putf;
320
Al Viro2903ff02012-08-28 12:52:22 -0400321 offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low,
Andrew Morton965c8e52012-12-17 15:59:39 -0800322 whence);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323
324 retval = (int)offset;
325 if (offset >= 0) {
326 retval = -EFAULT;
327 if (!copy_to_user(result, &offset, sizeof(offset)))
328 retval = 0;
329 }
330out_putf:
Eric Biggersd7a15f82014-03-16 14:24:08 -0500331 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 return retval;
333}
334#endif
335
Christoph Hellwigdbe4e192015-01-25 21:11:59 +0100336ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos)
337{
338 struct kiocb kiocb;
339 ssize_t ret;
340
341 if (!file->f_op->read_iter)
342 return -EINVAL;
343
344 init_sync_kiocb(&kiocb, file);
345 kiocb.ki_pos = *ppos;
346 kiocb.ki_nbytes = iov_iter_count(iter);
347
348 iter->type |= READ;
349 ret = file->f_op->read_iter(&kiocb, iter);
350 if (ret == -EIOCBQUEUED)
351 ret = wait_on_sync_kiocb(&kiocb);
352
353 if (ret > 0)
354 *ppos = kiocb.ki_pos;
355 return ret;
356}
357EXPORT_SYMBOL(vfs_iter_read);
358
359ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos)
360{
361 struct kiocb kiocb;
362 ssize_t ret;
363
364 if (!file->f_op->write_iter)
365 return -EINVAL;
366
367 init_sync_kiocb(&kiocb, file);
368 kiocb.ki_pos = *ppos;
369 kiocb.ki_nbytes = iov_iter_count(iter);
370
371 iter->type |= WRITE;
372 ret = file->f_op->write_iter(&kiocb, iter);
373 if (ret == -EIOCBQUEUED)
374 ret = wait_on_sync_kiocb(&kiocb);
375
376 if (ret > 0)
377 *ppos = kiocb.ki_pos;
378 return ret;
379}
380EXPORT_SYMBOL(vfs_iter_write);
381
Linus Torvaldse28cc712006-01-04 16:20:40 -0800382/*
383 * rw_verify_area doesn't like huge counts. We limit
384 * them to something that fits in "int" so that others
385 * won't have to do range checks all the time.
386 */
Al Viro68d70d02013-06-19 15:26:04 +0400387int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388{
389 struct inode *inode;
390 loff_t pos;
James Morrisc43e2592008-01-12 22:05:48 +1100391 int retval = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
Al Viro496ad9a2013-01-23 17:07:38 -0500393 inode = file_inode(file);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800394 if (unlikely((ssize_t) count < 0))
James Morrisc43e2592008-01-12 22:05:48 +1100395 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 pos = *ppos;
Al Virocccb5a12010-12-17 07:44:05 -0500397 if (unlikely(pos < 0)) {
398 if (!unsigned_offsets(file))
399 return retval;
400 if (count >= -pos) /* both values are in 0..LLONG_MAX */
401 return -EOVERFLOW;
402 } else if (unlikely((loff_t) (pos + count) < 0)) {
403 if (!unsigned_offsets(file))
KAMEZAWA Hiroyuki4a3956c2010-10-01 14:20:22 -0700404 return retval;
405 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406
Jeff Laytonbd61e0a2015-01-16 15:05:55 -0500407 if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
James Morrisc43e2592008-01-12 22:05:48 +1100408 retval = locks_mandatory_area(
Linus Torvaldse28cc712006-01-04 16:20:40 -0800409 read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE,
410 inode, file, pos, count);
411 if (retval < 0)
412 return retval;
413 }
James Morrisc43e2592008-01-12 22:05:48 +1100414 retval = security_file_permission(file,
415 read_write == READ ? MAY_READ : MAY_WRITE);
416 if (retval)
417 return retval;
Linus Torvaldse28cc712006-01-04 16:20:40 -0800418 return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419}
420
421ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
422{
Badari Pulavarty027445c2006-09-30 23:28:46 -0700423 struct iovec iov = { .iov_base = buf, .iov_len = len };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 struct kiocb kiocb;
425 ssize_t ret;
426
427 init_sync_kiocb(&kiocb, filp);
428 kiocb.ki_pos = *ppos;
David Howells61964eb2010-03-24 17:09:19 +0000429 kiocb.ki_nbytes = len;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700430
Zach Brown41003a72013-05-07 16:18:25 -0700431 ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432 if (-EIOCBQUEUED == ret)
433 ret = wait_on_sync_kiocb(&kiocb);
434 *ppos = kiocb.ki_pos;
435 return ret;
436}
437
438EXPORT_SYMBOL(do_sync_read);
439
Al Viro293bc982014-02-11 18:37:41 -0500440ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
441{
442 struct iovec iov = { .iov_base = buf, .iov_len = len };
443 struct kiocb kiocb;
444 struct iov_iter iter;
445 ssize_t ret;
446
447 init_sync_kiocb(&kiocb, filp);
448 kiocb.ki_pos = *ppos;
449 kiocb.ki_nbytes = len;
450 iov_iter_init(&iter, READ, &iov, 1, len);
451
452 ret = filp->f_op->read_iter(&kiocb, &iter);
453 if (-EIOCBQUEUED == ret)
454 ret = wait_on_sync_kiocb(&kiocb);
455 *ppos = kiocb.ki_pos;
456 return ret;
457}
458
459EXPORT_SYMBOL(new_sync_read);
460
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200461ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
462 loff_t *pos)
463{
464 ssize_t ret;
465
466 if (file->f_op->read)
467 ret = file->f_op->read(file, buf, count, pos);
468 else if (file->f_op->aio_read)
469 ret = do_sync_read(file, buf, count, pos);
470 else if (file->f_op->read_iter)
471 ret = new_sync_read(file, buf, count, pos);
472 else
473 ret = -EINVAL;
474
475 return ret;
476}
477
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
479{
480 ssize_t ret;
481
482 if (!(file->f_mode & FMODE_READ))
483 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500484 if (!(file->f_mode & FMODE_CAN_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 return -EINVAL;
486 if (unlikely(!access_ok(VERIFY_WRITE, buf, count)))
487 return -EFAULT;
488
489 ret = rw_verify_area(READ, file, pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800490 if (ret >= 0) {
491 count = ret;
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200492 ret = __vfs_read(file, buf, count, pos);
James Morrisc43e2592008-01-12 22:05:48 +1100493 if (ret > 0) {
Eric Paris2a12a9d2009-12-17 21:24:21 -0500494 fsnotify_access(file);
James Morrisc43e2592008-01-12 22:05:48 +1100495 add_rchar(current, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 }
James Morrisc43e2592008-01-12 22:05:48 +1100497 inc_syscr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 }
499
500 return ret;
501}
502
503EXPORT_SYMBOL(vfs_read);
504
505ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
506{
Badari Pulavarty027445c2006-09-30 23:28:46 -0700507 struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 struct kiocb kiocb;
509 ssize_t ret;
510
511 init_sync_kiocb(&kiocb, filp);
512 kiocb.ki_pos = *ppos;
David Howells61964eb2010-03-24 17:09:19 +0000513 kiocb.ki_nbytes = len;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700514
Zach Brown41003a72013-05-07 16:18:25 -0700515 ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 if (-EIOCBQUEUED == ret)
517 ret = wait_on_sync_kiocb(&kiocb);
518 *ppos = kiocb.ki_pos;
519 return ret;
520}
521
522EXPORT_SYMBOL(do_sync_write);
523
Al Viro293bc982014-02-11 18:37:41 -0500524ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
525{
526 struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
527 struct kiocb kiocb;
528 struct iov_iter iter;
529 ssize_t ret;
530
531 init_sync_kiocb(&kiocb, filp);
532 kiocb.ki_pos = *ppos;
533 kiocb.ki_nbytes = len;
534 iov_iter_init(&iter, WRITE, &iov, 1, len);
535
536 ret = filp->f_op->write_iter(&kiocb, &iter);
537 if (-EIOCBQUEUED == ret)
538 ret = wait_on_sync_kiocb(&kiocb);
539 *ppos = kiocb.ki_pos;
540 return ret;
541}
542
543EXPORT_SYMBOL(new_sync_write);
544
Al Viro06ae43f2013-03-20 13:19:30 -0400545ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos)
546{
547 mm_segment_t old_fs;
548 const char __user *p;
549 ssize_t ret;
550
Al Viro7f7f25e2014-02-11 17:49:24 -0500551 if (!(file->f_mode & FMODE_CAN_WRITE))
Al Viro3e84f482013-03-27 15:20:30 +0000552 return -EINVAL;
553
Al Viro06ae43f2013-03-20 13:19:30 -0400554 old_fs = get_fs();
555 set_fs(get_ds());
556 p = (__force const char __user *)buf;
557 if (count > MAX_RW_COUNT)
558 count = MAX_RW_COUNT;
559 if (file->f_op->write)
560 ret = file->f_op->write(file, p, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500561 else if (file->f_op->aio_write)
Al Viro06ae43f2013-03-20 13:19:30 -0400562 ret = do_sync_write(file, p, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500563 else
564 ret = new_sync_write(file, p, count, pos);
Al Viro06ae43f2013-03-20 13:19:30 -0400565 set_fs(old_fs);
566 if (ret > 0) {
567 fsnotify_modify(file);
568 add_wchar(current, ret);
569 }
570 inc_syscw(current);
571 return ret;
572}
573
Al Viro2ec3a122014-08-19 11:48:09 -0400574EXPORT_SYMBOL(__kernel_write);
575
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos)
577{
578 ssize_t ret;
579
580 if (!(file->f_mode & FMODE_WRITE))
581 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500582 if (!(file->f_mode & FMODE_CAN_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 return -EINVAL;
584 if (unlikely(!access_ok(VERIFY_READ, buf, count)))
585 return -EFAULT;
586
587 ret = rw_verify_area(WRITE, file, pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800588 if (ret >= 0) {
589 count = ret;
Al Viro03d95eb2013-03-20 13:04:20 -0400590 file_start_write(file);
James Morrisc43e2592008-01-12 22:05:48 +1100591 if (file->f_op->write)
592 ret = file->f_op->write(file, buf, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500593 else if (file->f_op->aio_write)
James Morrisc43e2592008-01-12 22:05:48 +1100594 ret = do_sync_write(file, buf, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500595 else
596 ret = new_sync_write(file, buf, count, pos);
James Morrisc43e2592008-01-12 22:05:48 +1100597 if (ret > 0) {
Eric Paris2a12a9d2009-12-17 21:24:21 -0500598 fsnotify_modify(file);
James Morrisc43e2592008-01-12 22:05:48 +1100599 add_wchar(current, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 }
James Morrisc43e2592008-01-12 22:05:48 +1100601 inc_syscw(current);
Al Viro03d95eb2013-03-20 13:04:20 -0400602 file_end_write(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 }
604
605 return ret;
606}
607
608EXPORT_SYMBOL(vfs_write);
609
610static inline loff_t file_pos_read(struct file *file)
611{
612 return file->f_pos;
613}
614
615static inline void file_pos_write(struct file *file, loff_t pos)
616{
617 file->f_pos = pos;
618}
619
Heiko Carstens3cdad422009-01-14 14:14:22 +0100620SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800622 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Al Viro2903ff02012-08-28 12:52:22 -0400625 if (f.file) {
626 loff_t pos = file_pos_read(f.file);
627 ret = vfs_read(f.file, buf, count, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400628 if (ret >= 0)
629 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800630 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 return ret;
633}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634
Heiko Carstens3cdad422009-01-14 14:14:22 +0100635SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
636 size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800638 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640
Al Viro2903ff02012-08-28 12:52:22 -0400641 if (f.file) {
642 loff_t pos = file_pos_read(f.file);
643 ret = vfs_write(f.file, buf, count, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400644 if (ret >= 0)
645 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800646 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 }
648
649 return ret;
650}
651
Al Viro4a0fd5b2013-01-21 15:16:58 -0500652SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf,
653 size_t, count, loff_t, pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654{
Al Viro2903ff02012-08-28 12:52:22 -0400655 struct fd f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657
658 if (pos < 0)
659 return -EINVAL;
660
Al Viro2903ff02012-08-28 12:52:22 -0400661 f = fdget(fd);
662 if (f.file) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400664 if (f.file->f_mode & FMODE_PREAD)
665 ret = vfs_read(f.file, buf, count, &pos);
666 fdput(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 }
668
669 return ret;
670}
671
Al Viro4a0fd5b2013-01-21 15:16:58 -0500672SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf,
673 size_t, count, loff_t, pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674{
Al Viro2903ff02012-08-28 12:52:22 -0400675 struct fd f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677
678 if (pos < 0)
679 return -EINVAL;
680
Al Viro2903ff02012-08-28 12:52:22 -0400681 f = fdget(fd);
682 if (f.file) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400684 if (f.file->f_mode & FMODE_PWRITE)
685 ret = vfs_write(f.file, buf, count, &pos);
686 fdput(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 }
688
689 return ret;
690}
691
692/*
693 * Reduce an iovec's length in-place. Return the resulting number of segments
694 */
695unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to)
696{
697 unsigned long seg = 0;
698 size_t len = 0;
699
700 while (seg < nr_segs) {
701 seg++;
702 if (len + iov->iov_len >= to) {
703 iov->iov_len = to - len;
704 break;
705 }
706 len += iov->iov_len;
707 iov++;
708 }
709 return seg;
710}
Eric Sandeen19295522008-01-28 23:58:27 -0500711EXPORT_SYMBOL(iov_shorten);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712
Al Viro293bc982014-02-11 18:37:41 -0500713static ssize_t do_iter_readv_writev(struct file *filp, int rw, const struct iovec *iov,
714 unsigned long nr_segs, size_t len, loff_t *ppos, iter_fn_t fn)
715{
716 struct kiocb kiocb;
717 struct iov_iter iter;
718 ssize_t ret;
719
720 init_sync_kiocb(&kiocb, filp);
721 kiocb.ki_pos = *ppos;
722 kiocb.ki_nbytes = len;
723
724 iov_iter_init(&iter, rw, iov, nr_segs, len);
725 ret = fn(&kiocb, &iter);
726 if (ret == -EIOCBQUEUED)
727 ret = wait_on_sync_kiocb(&kiocb);
728 *ppos = kiocb.ki_pos;
729 return ret;
730}
731
Al Viro72ec3512013-03-20 10:42:10 -0400732static ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700733 unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn)
734{
735 struct kiocb kiocb;
736 ssize_t ret;
737
738 init_sync_kiocb(&kiocb, filp);
739 kiocb.ki_pos = *ppos;
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700740 kiocb.ki_nbytes = len;
741
Zach Brown41003a72013-05-07 16:18:25 -0700742 ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos);
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700743 if (ret == -EIOCBQUEUED)
744 ret = wait_on_sync_kiocb(&kiocb);
745 *ppos = kiocb.ki_pos;
746 return ret;
747}
748
749/* Do it by hand, with file-ops */
Al Viro72ec3512013-03-20 10:42:10 -0400750static ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700751 unsigned long nr_segs, loff_t *ppos, io_fn_t fn)
752{
753 struct iovec *vector = iov;
754 ssize_t ret = 0;
755
756 while (nr_segs > 0) {
757 void __user *base;
758 size_t len;
759 ssize_t nr;
760
761 base = vector->iov_base;
762 len = vector->iov_len;
763 vector++;
764 nr_segs--;
765
766 nr = fn(filp, base, len, ppos);
767
768 if (nr < 0) {
769 if (!ret)
770 ret = nr;
771 break;
772 }
773 ret += nr;
774 if (nr != len)
775 break;
776 }
777
778 return ret;
779}
780
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781/* A write operation does a read from user space and vice versa */
782#define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
783
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700784ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
785 unsigned long nr_segs, unsigned long fast_segs,
786 struct iovec *fast_pointer,
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700787 struct iovec **ret_pointer)
Linus Torvalds435f49a2010-10-29 10:36:49 -0700788{
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700789 unsigned long seg;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700790 ssize_t ret;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700791 struct iovec *iov = fast_pointer;
792
Linus Torvalds435f49a2010-10-29 10:36:49 -0700793 /*
794 * SuS says "The readv() function *may* fail if the iovcnt argument
795 * was less than or equal to 0, or greater than {IOV_MAX}. Linux has
796 * traditionally returned zero for zero segments, so...
797 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700798 if (nr_segs == 0) {
799 ret = 0;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700800 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700801 }
802
Linus Torvalds435f49a2010-10-29 10:36:49 -0700803 /*
804 * First get the "struct iovec" from user memory and
805 * verify all the pointers
806 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700807 if (nr_segs > UIO_MAXIOV) {
808 ret = -EINVAL;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700809 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700810 }
811 if (nr_segs > fast_segs) {
Linus Torvalds435f49a2010-10-29 10:36:49 -0700812 iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700813 if (iov == NULL) {
814 ret = -ENOMEM;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700815 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700816 }
Linus Torvalds435f49a2010-10-29 10:36:49 -0700817 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700818 if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) {
819 ret = -EFAULT;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700820 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700821 }
822
Linus Torvalds435f49a2010-10-29 10:36:49 -0700823 /*
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700824 * According to the Single Unix Specification we should return EINVAL
825 * if an element length is < 0 when cast to ssize_t or if the
826 * total length would overflow the ssize_t return value of the
827 * system call.
Linus Torvalds435f49a2010-10-29 10:36:49 -0700828 *
829 * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the
830 * overflow case.
831 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700832 ret = 0;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700833 for (seg = 0; seg < nr_segs; seg++) {
834 void __user *buf = iov[seg].iov_base;
835 ssize_t len = (ssize_t)iov[seg].iov_len;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700836
837 /* see if we we're about to use an invalid len or if
838 * it's about to overflow ssize_t */
Linus Torvalds435f49a2010-10-29 10:36:49 -0700839 if (len < 0) {
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700840 ret = -EINVAL;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700841 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700842 }
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700843 if (type >= 0
Christopher Yeohfcf63402011-10-31 17:06:39 -0700844 && unlikely(!access_ok(vrfy_dir(type), buf, len))) {
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700845 ret = -EFAULT;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700846 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700847 }
Linus Torvalds435f49a2010-10-29 10:36:49 -0700848 if (len > MAX_RW_COUNT - ret) {
849 len = MAX_RW_COUNT - ret;
850 iov[seg].iov_len = len;
851 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700852 ret += len;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700853 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700854out:
855 *ret_pointer = iov;
856 return ret;
857}
858
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859static ssize_t do_readv_writev(int type, struct file *file,
860 const struct iovec __user * uvector,
861 unsigned long nr_segs, loff_t *pos)
862{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 size_t tot_len;
864 struct iovec iovstack[UIO_FASTIOV];
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700865 struct iovec *iov = iovstack;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 ssize_t ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 io_fn_t fn;
868 iov_fn_t fnv;
Al Viro293bc982014-02-11 18:37:41 -0500869 iter_fn_t iter_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700871 ret = rw_copy_check_uvector(type, uvector, nr_segs,
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700872 ARRAY_SIZE(iovstack), iovstack, &iov);
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700873 if (ret <= 0)
874 goto out;
875
876 tot_len = ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 ret = rw_verify_area(type, file, pos, tot_len);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800878 if (ret < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 goto out;
880
881 fnv = NULL;
882 if (type == READ) {
883 fn = file->f_op->read;
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700884 fnv = file->f_op->aio_read;
Al Viro293bc982014-02-11 18:37:41 -0500885 iter_fn = file->f_op->read_iter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 } else {
887 fn = (io_fn_t)file->f_op->write;
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700888 fnv = file->f_op->aio_write;
Al Viro293bc982014-02-11 18:37:41 -0500889 iter_fn = file->f_op->write_iter;
Al Viro03d95eb2013-03-20 13:04:20 -0400890 file_start_write(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891 }
892
Al Viro293bc982014-02-11 18:37:41 -0500893 if (iter_fn)
894 ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len,
895 pos, iter_fn);
896 else if (fnv)
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700897 ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
898 pos, fnv);
899 else
900 ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901
Al Viro03d95eb2013-03-20 13:04:20 -0400902 if (type != READ)
903 file_end_write(file);
904
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905out:
906 if (iov != iovstack)
907 kfree(iov);
Robert Love0eeca282005-07-12 17:06:03 -0400908 if ((ret + (type == READ)) > 0) {
909 if (type == READ)
Eric Paris2a12a9d2009-12-17 21:24:21 -0500910 fsnotify_access(file);
Robert Love0eeca282005-07-12 17:06:03 -0400911 else
Eric Paris2a12a9d2009-12-17 21:24:21 -0500912 fsnotify_modify(file);
Robert Love0eeca282005-07-12 17:06:03 -0400913 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915}
916
917ssize_t vfs_readv(struct file *file, const struct iovec __user *vec,
918 unsigned long vlen, loff_t *pos)
919{
920 if (!(file->f_mode & FMODE_READ))
921 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500922 if (!(file->f_mode & FMODE_CAN_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923 return -EINVAL;
924
925 return do_readv_writev(READ, file, vec, vlen, pos);
926}
927
928EXPORT_SYMBOL(vfs_readv);
929
930ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
931 unsigned long vlen, loff_t *pos)
932{
933 if (!(file->f_mode & FMODE_WRITE))
934 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500935 if (!(file->f_mode & FMODE_CAN_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 return -EINVAL;
937
938 return do_readv_writev(WRITE, file, vec, vlen, pos);
939}
940
941EXPORT_SYMBOL(vfs_writev);
942
Heiko Carstens3cdad422009-01-14 14:14:22 +0100943SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec,
944 unsigned long, vlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800946 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948
Al Viro2903ff02012-08-28 12:52:22 -0400949 if (f.file) {
950 loff_t pos = file_pos_read(f.file);
951 ret = vfs_readv(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400952 if (ret >= 0)
953 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800954 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955 }
956
957 if (ret > 0)
Alexey Dobriyan4b98d112007-02-10 01:46:45 -0800958 add_rchar(current, ret);
959 inc_syscr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960 return ret;
961}
962
Heiko Carstens3cdad422009-01-14 14:14:22 +0100963SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
964 unsigned long, vlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700965{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800966 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968
Al Viro2903ff02012-08-28 12:52:22 -0400969 if (f.file) {
970 loff_t pos = file_pos_read(f.file);
971 ret = vfs_writev(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400972 if (ret >= 0)
973 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800974 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 }
976
977 if (ret > 0)
Alexey Dobriyan4b98d112007-02-10 01:46:45 -0800978 add_wchar(current, ret);
979 inc_syscw(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 return ret;
981}
982
Linus Torvalds601cc112009-04-03 08:03:22 -0700983static inline loff_t pos_from_hilo(unsigned long high, unsigned long low)
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700984{
Linus Torvalds601cc112009-04-03 08:03:22 -0700985#define HALF_LONG_BITS (BITS_PER_LONG / 2)
986 return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low;
987}
988
989SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec,
990 unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
991{
992 loff_t pos = pos_from_hilo(pos_h, pos_l);
Al Viro2903ff02012-08-28 12:52:22 -0400993 struct fd f;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700994 ssize_t ret = -EBADF;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700995
996 if (pos < 0)
997 return -EINVAL;
998
Al Viro2903ff02012-08-28 12:52:22 -0400999 f = fdget(fd);
1000 if (f.file) {
Gerd Hoffmannf3554f42009-04-02 16:59:23 -07001001 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -04001002 if (f.file->f_mode & FMODE_PREAD)
1003 ret = vfs_readv(f.file, vec, vlen, &pos);
1004 fdput(f);
Gerd Hoffmannf3554f42009-04-02 16:59:23 -07001005 }
1006
1007 if (ret > 0)
1008 add_rchar(current, ret);
1009 inc_syscr(current);
1010 return ret;
1011}
1012
1013SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec,
Linus Torvalds601cc112009-04-03 08:03:22 -07001014 unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
Gerd Hoffmannf3554f42009-04-02 16:59:23 -07001015{
Linus Torvalds601cc112009-04-03 08:03:22 -07001016 loff_t pos = pos_from_hilo(pos_h, pos_l);
Al Viro2903ff02012-08-28 12:52:22 -04001017 struct fd f;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -07001018 ssize_t ret = -EBADF;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -07001019
1020 if (pos < 0)
1021 return -EINVAL;
1022
Al Viro2903ff02012-08-28 12:52:22 -04001023 f = fdget(fd);
1024 if (f.file) {
Gerd Hoffmannf3554f42009-04-02 16:59:23 -07001025 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -04001026 if (f.file->f_mode & FMODE_PWRITE)
1027 ret = vfs_writev(f.file, vec, vlen, &pos);
1028 fdput(f);
Gerd Hoffmannf3554f42009-04-02 16:59:23 -07001029 }
1030
1031 if (ret > 0)
1032 add_wchar(current, ret);
1033 inc_syscw(current);
1034 return ret;
1035}
1036
Al Viro72ec3512013-03-20 10:42:10 -04001037#ifdef CONFIG_COMPAT
1038
1039static ssize_t compat_do_readv_writev(int type, struct file *file,
1040 const struct compat_iovec __user *uvector,
1041 unsigned long nr_segs, loff_t *pos)
1042{
1043 compat_ssize_t tot_len;
1044 struct iovec iovstack[UIO_FASTIOV];
1045 struct iovec *iov = iovstack;
1046 ssize_t ret;
1047 io_fn_t fn;
1048 iov_fn_t fnv;
Al Viro293bc982014-02-11 18:37:41 -05001049 iter_fn_t iter_fn;
Al Viro72ec3512013-03-20 10:42:10 -04001050
Al Viro72ec3512013-03-20 10:42:10 -04001051 ret = compat_rw_copy_check_uvector(type, uvector, nr_segs,
1052 UIO_FASTIOV, iovstack, &iov);
1053 if (ret <= 0)
1054 goto out;
1055
1056 tot_len = ret;
1057 ret = rw_verify_area(type, file, pos, tot_len);
1058 if (ret < 0)
1059 goto out;
1060
1061 fnv = NULL;
1062 if (type == READ) {
1063 fn = file->f_op->read;
1064 fnv = file->f_op->aio_read;
Al Viro293bc982014-02-11 18:37:41 -05001065 iter_fn = file->f_op->read_iter;
Al Viro72ec3512013-03-20 10:42:10 -04001066 } else {
1067 fn = (io_fn_t)file->f_op->write;
1068 fnv = file->f_op->aio_write;
Al Viro293bc982014-02-11 18:37:41 -05001069 iter_fn = file->f_op->write_iter;
Al Viro03d95eb2013-03-20 13:04:20 -04001070 file_start_write(file);
Al Viro72ec3512013-03-20 10:42:10 -04001071 }
1072
Al Viro293bc982014-02-11 18:37:41 -05001073 if (iter_fn)
1074 ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len,
1075 pos, iter_fn);
1076 else if (fnv)
Al Viro72ec3512013-03-20 10:42:10 -04001077 ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
1078 pos, fnv);
Al Viro03d95eb2013-03-20 13:04:20 -04001079 else
Al Viro72ec3512013-03-20 10:42:10 -04001080 ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
1081
Al Viro03d95eb2013-03-20 13:04:20 -04001082 if (type != READ)
1083 file_end_write(file);
1084
Al Viro72ec3512013-03-20 10:42:10 -04001085out:
1086 if (iov != iovstack)
1087 kfree(iov);
1088 if ((ret + (type == READ)) > 0) {
1089 if (type == READ)
1090 fsnotify_access(file);
1091 else
1092 fsnotify_modify(file);
1093 }
1094 return ret;
1095}
1096
1097static size_t compat_readv(struct file *file,
1098 const struct compat_iovec __user *vec,
1099 unsigned long vlen, loff_t *pos)
1100{
1101 ssize_t ret = -EBADF;
1102
1103 if (!(file->f_mode & FMODE_READ))
1104 goto out;
1105
1106 ret = -EINVAL;
Al Viro7f7f25e2014-02-11 17:49:24 -05001107 if (!(file->f_mode & FMODE_CAN_READ))
Al Viro72ec3512013-03-20 10:42:10 -04001108 goto out;
1109
1110 ret = compat_do_readv_writev(READ, file, vec, vlen, pos);
1111
1112out:
1113 if (ret > 0)
1114 add_rchar(current, ret);
1115 inc_syscr(current);
1116 return ret;
1117}
1118
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001119COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001120 const struct compat_iovec __user *,vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001121 compat_ulong_t, vlen)
Al Viro72ec3512013-03-20 10:42:10 -04001122{
Linus Torvalds9c225f22014-03-03 09:36:58 -08001123 struct fd f = fdget_pos(fd);
Al Viro72ec3512013-03-20 10:42:10 -04001124 ssize_t ret;
1125 loff_t pos;
1126
1127 if (!f.file)
1128 return -EBADF;
1129 pos = f.file->f_pos;
1130 ret = compat_readv(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +04001131 if (ret >= 0)
1132 f.file->f_pos = pos;
Linus Torvalds9c225f22014-03-03 09:36:58 -08001133 fdput_pos(f);
Al Viro72ec3512013-03-20 10:42:10 -04001134 return ret;
1135}
1136
Heiko Carstens378a10f2014-03-05 10:43:51 +01001137static long __compat_sys_preadv64(unsigned long fd,
1138 const struct compat_iovec __user *vec,
1139 unsigned long vlen, loff_t pos)
Al Viro72ec3512013-03-20 10:42:10 -04001140{
1141 struct fd f;
1142 ssize_t ret;
1143
1144 if (pos < 0)
1145 return -EINVAL;
1146 f = fdget(fd);
1147 if (!f.file)
1148 return -EBADF;
1149 ret = -ESPIPE;
1150 if (f.file->f_mode & FMODE_PREAD)
1151 ret = compat_readv(f.file, vec, vlen, &pos);
1152 fdput(f);
1153 return ret;
1154}
1155
Heiko Carstens378a10f2014-03-05 10:43:51 +01001156#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64
1157COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd,
1158 const struct compat_iovec __user *,vec,
1159 unsigned long, vlen, loff_t, pos)
1160{
1161 return __compat_sys_preadv64(fd, vec, vlen, pos);
1162}
1163#endif
1164
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001165COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001166 const struct compat_iovec __user *,vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001167 compat_ulong_t, vlen, u32, pos_low, u32, pos_high)
Al Viro72ec3512013-03-20 10:42:10 -04001168{
1169 loff_t pos = ((loff_t)pos_high << 32) | pos_low;
Heiko Carstens378a10f2014-03-05 10:43:51 +01001170
1171 return __compat_sys_preadv64(fd, vec, vlen, pos);
Al Viro72ec3512013-03-20 10:42:10 -04001172}
1173
1174static size_t compat_writev(struct file *file,
1175 const struct compat_iovec __user *vec,
1176 unsigned long vlen, loff_t *pos)
1177{
1178 ssize_t ret = -EBADF;
1179
1180 if (!(file->f_mode & FMODE_WRITE))
1181 goto out;
1182
1183 ret = -EINVAL;
Al Viro7f7f25e2014-02-11 17:49:24 -05001184 if (!(file->f_mode & FMODE_CAN_WRITE))
Al Viro72ec3512013-03-20 10:42:10 -04001185 goto out;
1186
1187 ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos);
1188
1189out:
1190 if (ret > 0)
1191 add_wchar(current, ret);
1192 inc_syscw(current);
1193 return ret;
1194}
1195
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001196COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001197 const struct compat_iovec __user *, vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001198 compat_ulong_t, vlen)
Al Viro72ec3512013-03-20 10:42:10 -04001199{
Linus Torvalds9c225f22014-03-03 09:36:58 -08001200 struct fd f = fdget_pos(fd);
Al Viro72ec3512013-03-20 10:42:10 -04001201 ssize_t ret;
1202 loff_t pos;
1203
1204 if (!f.file)
1205 return -EBADF;
1206 pos = f.file->f_pos;
1207 ret = compat_writev(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +04001208 if (ret >= 0)
1209 f.file->f_pos = pos;
Linus Torvalds9c225f22014-03-03 09:36:58 -08001210 fdput_pos(f);
Al Viro72ec3512013-03-20 10:42:10 -04001211 return ret;
1212}
1213
Heiko Carstens378a10f2014-03-05 10:43:51 +01001214static long __compat_sys_pwritev64(unsigned long fd,
1215 const struct compat_iovec __user *vec,
1216 unsigned long vlen, loff_t pos)
Al Viro72ec3512013-03-20 10:42:10 -04001217{
1218 struct fd f;
1219 ssize_t ret;
1220
1221 if (pos < 0)
1222 return -EINVAL;
1223 f = fdget(fd);
1224 if (!f.file)
1225 return -EBADF;
1226 ret = -ESPIPE;
1227 if (f.file->f_mode & FMODE_PWRITE)
1228 ret = compat_writev(f.file, vec, vlen, &pos);
1229 fdput(f);
1230 return ret;
1231}
1232
Heiko Carstens378a10f2014-03-05 10:43:51 +01001233#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64
1234COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd,
1235 const struct compat_iovec __user *,vec,
1236 unsigned long, vlen, loff_t, pos)
1237{
1238 return __compat_sys_pwritev64(fd, vec, vlen, pos);
1239}
1240#endif
1241
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001242COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001243 const struct compat_iovec __user *,vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001244 compat_ulong_t, vlen, u32, pos_low, u32, pos_high)
Al Viro72ec3512013-03-20 10:42:10 -04001245{
1246 loff_t pos = ((loff_t)pos_high << 32) | pos_low;
Heiko Carstens378a10f2014-03-05 10:43:51 +01001247
1248 return __compat_sys_pwritev64(fd, vec, vlen, pos);
Al Viro72ec3512013-03-20 10:42:10 -04001249}
1250#endif
1251
Al Viro19f4fc32013-02-24 02:17:03 -05001252static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
1253 size_t count, loff_t max)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254{
Al Viro2903ff02012-08-28 12:52:22 -04001255 struct fd in, out;
1256 struct inode *in_inode, *out_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257 loff_t pos;
Al Viro7995bd22013-06-20 18:58:36 +04001258 loff_t out_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259 ssize_t retval;
Al Viro2903ff02012-08-28 12:52:22 -04001260 int fl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001261
1262 /*
1263 * Get input file, and verify that it is ok..
1264 */
1265 retval = -EBADF;
Al Viro2903ff02012-08-28 12:52:22 -04001266 in = fdget(in_fd);
1267 if (!in.file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268 goto out;
Al Viro2903ff02012-08-28 12:52:22 -04001269 if (!(in.file->f_mode & FMODE_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001270 goto fput_in;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001271 retval = -ESPIPE;
Al Viro7995bd22013-06-20 18:58:36 +04001272 if (!ppos) {
1273 pos = in.file->f_pos;
1274 } else {
1275 pos = *ppos;
Al Viro2903ff02012-08-28 12:52:22 -04001276 if (!(in.file->f_mode & FMODE_PREAD))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 goto fput_in;
Al Viro7995bd22013-06-20 18:58:36 +04001278 }
1279 retval = rw_verify_area(READ, in.file, &pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -08001280 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281 goto fput_in;
Linus Torvaldse28cc712006-01-04 16:20:40 -08001282 count = retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283
Linus Torvalds1da177e2005-04-16 15:20:36 -07001284 /*
1285 * Get output file, and verify that it is ok..
1286 */
1287 retval = -EBADF;
Al Viro2903ff02012-08-28 12:52:22 -04001288 out = fdget(out_fd);
1289 if (!out.file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290 goto fput_in;
Al Viro2903ff02012-08-28 12:52:22 -04001291 if (!(out.file->f_mode & FMODE_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292 goto fput_out;
1293 retval = -EINVAL;
Al Viro496ad9a2013-01-23 17:07:38 -05001294 in_inode = file_inode(in.file);
1295 out_inode = file_inode(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001296 out_pos = out.file->f_pos;
1297 retval = rw_verify_area(WRITE, out.file, &out_pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -08001298 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 goto fput_out;
Linus Torvaldse28cc712006-01-04 16:20:40 -08001300 count = retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301
Linus Torvalds1da177e2005-04-16 15:20:36 -07001302 if (!max)
1303 max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
1304
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305 if (unlikely(pos + count > max)) {
1306 retval = -EOVERFLOW;
1307 if (pos >= max)
1308 goto fput_out;
1309 count = max - pos;
1310 }
1311
Jens Axboed96e6e72007-06-11 12:18:52 +02001312 fl = 0;
Jens Axboe534f2aa2007-06-01 14:52:37 +02001313#if 0
Jens Axboed96e6e72007-06-11 12:18:52 +02001314 /*
1315 * We need to debate whether we can enable this or not. The
1316 * man page documents EAGAIN return for the output at least,
1317 * and the application is arguably buggy if it doesn't expect
1318 * EAGAIN on a non-blocking file descriptor.
1319 */
Al Viro2903ff02012-08-28 12:52:22 -04001320 if (in.file->f_flags & O_NONBLOCK)
Jens Axboed96e6e72007-06-11 12:18:52 +02001321 fl = SPLICE_F_NONBLOCK;
Jens Axboe534f2aa2007-06-01 14:52:37 +02001322#endif
Al Viro50cd2c52013-05-23 20:10:34 -04001323 file_start_write(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001324 retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl);
Al Viro50cd2c52013-05-23 20:10:34 -04001325 file_end_write(out.file);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001326
1327 if (retval > 0) {
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001328 add_rchar(current, retval);
1329 add_wchar(current, retval);
Scott Wolchoka68c2f12012-12-20 15:05:52 -08001330 fsnotify_access(in.file);
1331 fsnotify_modify(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001332 out.file->f_pos = out_pos;
1333 if (ppos)
1334 *ppos = pos;
1335 else
1336 in.file->f_pos = pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001339 inc_syscr(current);
1340 inc_syscw(current);
Al Viro7995bd22013-06-20 18:58:36 +04001341 if (pos > max)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342 retval = -EOVERFLOW;
1343
1344fput_out:
Al Viro2903ff02012-08-28 12:52:22 -04001345 fdput(out);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346fput_in:
Al Viro2903ff02012-08-28 12:52:22 -04001347 fdput(in);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001348out:
1349 return retval;
1350}
1351
Heiko Carstens002c8972009-01-14 14:14:18 +01001352SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353{
1354 loff_t pos;
1355 off_t off;
1356 ssize_t ret;
1357
1358 if (offset) {
1359 if (unlikely(get_user(off, offset)))
1360 return -EFAULT;
1361 pos = off;
1362 ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
1363 if (unlikely(put_user(pos, offset)))
1364 return -EFAULT;
1365 return ret;
1366 }
1367
1368 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1369}
1370
Heiko Carstens002c8972009-01-14 14:14:18 +01001371SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372{
1373 loff_t pos;
1374 ssize_t ret;
1375
1376 if (offset) {
1377 if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
1378 return -EFAULT;
1379 ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
1380 if (unlikely(put_user(pos, offset)))
1381 return -EFAULT;
1382 return ret;
1383 }
1384
1385 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1386}
Al Viro19f4fc32013-02-24 02:17:03 -05001387
1388#ifdef CONFIG_COMPAT
1389COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd,
1390 compat_off_t __user *, offset, compat_size_t, count)
1391{
1392 loff_t pos;
1393 off_t off;
1394 ssize_t ret;
1395
1396 if (offset) {
1397 if (unlikely(get_user(off, offset)))
1398 return -EFAULT;
1399 pos = off;
1400 ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
1401 if (unlikely(put_user(pos, offset)))
1402 return -EFAULT;
1403 return ret;
1404 }
1405
1406 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1407}
1408
1409COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd,
1410 compat_loff_t __user *, offset, compat_size_t, count)
1411{
1412 loff_t pos;
1413 ssize_t ret;
1414
1415 if (offset) {
1416 if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
1417 return -EFAULT;
1418 ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
1419 if (unlikely(put_user(pos, offset)))
1420 return -EFAULT;
1421 return ret;
1422 }
1423
1424 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1425}
1426#endif