blob: c0805c93b6fa18d34b9b579d5c470af2a5a66b1b [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
Linus Torvaldse28cc712006-01-04 16:20:40 -0800336/*
337 * rw_verify_area doesn't like huge counts. We limit
338 * them to something that fits in "int" so that others
339 * won't have to do range checks all the time.
340 */
Al Viro68d70d02013-06-19 15:26:04 +0400341int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342{
343 struct inode *inode;
344 loff_t pos;
James Morrisc43e2592008-01-12 22:05:48 +1100345 int retval = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346
Al Viro496ad9a2013-01-23 17:07:38 -0500347 inode = file_inode(file);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800348 if (unlikely((ssize_t) count < 0))
James Morrisc43e2592008-01-12 22:05:48 +1100349 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 pos = *ppos;
Al Virocccb5a12010-12-17 07:44:05 -0500351 if (unlikely(pos < 0)) {
352 if (!unsigned_offsets(file))
353 return retval;
354 if (count >= -pos) /* both values are in 0..LLONG_MAX */
355 return -EOVERFLOW;
356 } else if (unlikely((loff_t) (pos + count) < 0)) {
357 if (!unsigned_offsets(file))
KAMEZAWA Hiroyuki4a3956c2010-10-01 14:20:22 -0700358 return retval;
359 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360
Pavel Emelyanova16877c2007-10-01 14:41:11 -0700361 if (unlikely(inode->i_flock && mandatory_lock(inode))) {
James Morrisc43e2592008-01-12 22:05:48 +1100362 retval = locks_mandatory_area(
Linus Torvaldse28cc712006-01-04 16:20:40 -0800363 read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE,
364 inode, file, pos, count);
365 if (retval < 0)
366 return retval;
367 }
James Morrisc43e2592008-01-12 22:05:48 +1100368 retval = security_file_permission(file,
369 read_write == READ ? MAY_READ : MAY_WRITE);
370 if (retval)
371 return retval;
Linus Torvaldse28cc712006-01-04 16:20:40 -0800372 return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373}
374
375ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
376{
Badari Pulavarty027445c2006-09-30 23:28:46 -0700377 struct iovec iov = { .iov_base = buf, .iov_len = len };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 struct kiocb kiocb;
379 ssize_t ret;
380
381 init_sync_kiocb(&kiocb, filp);
382 kiocb.ki_pos = *ppos;
David Howells61964eb2010-03-24 17:09:19 +0000383 kiocb.ki_nbytes = len;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700384
Zach Brown41003a72013-05-07 16:18:25 -0700385 ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 if (-EIOCBQUEUED == ret)
387 ret = wait_on_sync_kiocb(&kiocb);
388 *ppos = kiocb.ki_pos;
389 return ret;
390}
391
392EXPORT_SYMBOL(do_sync_read);
393
Al Viro293bc982014-02-11 18:37:41 -0500394ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
395{
396 struct iovec iov = { .iov_base = buf, .iov_len = len };
397 struct kiocb kiocb;
398 struct iov_iter iter;
399 ssize_t ret;
400
401 init_sync_kiocb(&kiocb, filp);
402 kiocb.ki_pos = *ppos;
403 kiocb.ki_nbytes = len;
404 iov_iter_init(&iter, READ, &iov, 1, len);
405
406 ret = filp->f_op->read_iter(&kiocb, &iter);
407 if (-EIOCBQUEUED == ret)
408 ret = wait_on_sync_kiocb(&kiocb);
409 *ppos = kiocb.ki_pos;
410 return ret;
411}
412
413EXPORT_SYMBOL(new_sync_read);
414
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200415ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
416 loff_t *pos)
417{
418 ssize_t ret;
419
420 if (file->f_op->read)
421 ret = file->f_op->read(file, buf, count, pos);
422 else if (file->f_op->aio_read)
423 ret = do_sync_read(file, buf, count, pos);
424 else if (file->f_op->read_iter)
425 ret = new_sync_read(file, buf, count, pos);
426 else
427 ret = -EINVAL;
428
429 return ret;
430}
431
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
433{
434 ssize_t ret;
435
436 if (!(file->f_mode & FMODE_READ))
437 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500438 if (!(file->f_mode & FMODE_CAN_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439 return -EINVAL;
440 if (unlikely(!access_ok(VERIFY_WRITE, buf, count)))
441 return -EFAULT;
442
443 ret = rw_verify_area(READ, file, pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800444 if (ret >= 0) {
445 count = ret;
Dmitry Kasatkin6fb50322014-11-05 17:01:17 +0200446 ret = __vfs_read(file, buf, count, pos);
James Morrisc43e2592008-01-12 22:05:48 +1100447 if (ret > 0) {
Eric Paris2a12a9d2009-12-17 21:24:21 -0500448 fsnotify_access(file);
James Morrisc43e2592008-01-12 22:05:48 +1100449 add_rchar(current, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 }
James Morrisc43e2592008-01-12 22:05:48 +1100451 inc_syscr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 }
453
454 return ret;
455}
456
457EXPORT_SYMBOL(vfs_read);
458
459ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
460{
Badari Pulavarty027445c2006-09-30 23:28:46 -0700461 struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 struct kiocb kiocb;
463 ssize_t ret;
464
465 init_sync_kiocb(&kiocb, filp);
466 kiocb.ki_pos = *ppos;
David Howells61964eb2010-03-24 17:09:19 +0000467 kiocb.ki_nbytes = len;
Badari Pulavarty027445c2006-09-30 23:28:46 -0700468
Zach Brown41003a72013-05-07 16:18:25 -0700469 ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 if (-EIOCBQUEUED == ret)
471 ret = wait_on_sync_kiocb(&kiocb);
472 *ppos = kiocb.ki_pos;
473 return ret;
474}
475
476EXPORT_SYMBOL(do_sync_write);
477
Al Viro293bc982014-02-11 18:37:41 -0500478ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
479{
480 struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
481 struct kiocb kiocb;
482 struct iov_iter iter;
483 ssize_t ret;
484
485 init_sync_kiocb(&kiocb, filp);
486 kiocb.ki_pos = *ppos;
487 kiocb.ki_nbytes = len;
488 iov_iter_init(&iter, WRITE, &iov, 1, len);
489
490 ret = filp->f_op->write_iter(&kiocb, &iter);
491 if (-EIOCBQUEUED == ret)
492 ret = wait_on_sync_kiocb(&kiocb);
493 *ppos = kiocb.ki_pos;
494 return ret;
495}
496
497EXPORT_SYMBOL(new_sync_write);
498
Al Viro06ae43f2013-03-20 13:19:30 -0400499ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos)
500{
501 mm_segment_t old_fs;
502 const char __user *p;
503 ssize_t ret;
504
Al Viro7f7f25e2014-02-11 17:49:24 -0500505 if (!(file->f_mode & FMODE_CAN_WRITE))
Al Viro3e84f482013-03-27 15:20:30 +0000506 return -EINVAL;
507
Al Viro06ae43f2013-03-20 13:19:30 -0400508 old_fs = get_fs();
509 set_fs(get_ds());
510 p = (__force const char __user *)buf;
511 if (count > MAX_RW_COUNT)
512 count = MAX_RW_COUNT;
513 if (file->f_op->write)
514 ret = file->f_op->write(file, p, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500515 else if (file->f_op->aio_write)
Al Viro06ae43f2013-03-20 13:19:30 -0400516 ret = do_sync_write(file, p, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500517 else
518 ret = new_sync_write(file, p, count, pos);
Al Viro06ae43f2013-03-20 13:19:30 -0400519 set_fs(old_fs);
520 if (ret > 0) {
521 fsnotify_modify(file);
522 add_wchar(current, ret);
523 }
524 inc_syscw(current);
525 return ret;
526}
527
Al Viro2ec3a122014-08-19 11:48:09 -0400528EXPORT_SYMBOL(__kernel_write);
529
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos)
531{
532 ssize_t ret;
533
534 if (!(file->f_mode & FMODE_WRITE))
535 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500536 if (!(file->f_mode & FMODE_CAN_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537 return -EINVAL;
538 if (unlikely(!access_ok(VERIFY_READ, buf, count)))
539 return -EFAULT;
540
541 ret = rw_verify_area(WRITE, file, pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800542 if (ret >= 0) {
543 count = ret;
Al Viro03d95eb2013-03-20 13:04:20 -0400544 file_start_write(file);
James Morrisc43e2592008-01-12 22:05:48 +1100545 if (file->f_op->write)
546 ret = file->f_op->write(file, buf, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500547 else if (file->f_op->aio_write)
James Morrisc43e2592008-01-12 22:05:48 +1100548 ret = do_sync_write(file, buf, count, pos);
Al Viro293bc982014-02-11 18:37:41 -0500549 else
550 ret = new_sync_write(file, buf, count, pos);
James Morrisc43e2592008-01-12 22:05:48 +1100551 if (ret > 0) {
Eric Paris2a12a9d2009-12-17 21:24:21 -0500552 fsnotify_modify(file);
James Morrisc43e2592008-01-12 22:05:48 +1100553 add_wchar(current, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 }
James Morrisc43e2592008-01-12 22:05:48 +1100555 inc_syscw(current);
Al Viro03d95eb2013-03-20 13:04:20 -0400556 file_end_write(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 }
558
559 return ret;
560}
561
562EXPORT_SYMBOL(vfs_write);
563
564static inline loff_t file_pos_read(struct file *file)
565{
566 return file->f_pos;
567}
568
569static inline void file_pos_write(struct file *file, loff_t pos)
570{
571 file->f_pos = pos;
572}
573
Heiko Carstens3cdad422009-01-14 14:14:22 +0100574SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800576 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578
Al Viro2903ff02012-08-28 12:52:22 -0400579 if (f.file) {
580 loff_t pos = file_pos_read(f.file);
581 ret = vfs_read(f.file, buf, count, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400582 if (ret >= 0)
583 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800584 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 return ret;
587}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588
Heiko Carstens3cdad422009-01-14 14:14:22 +0100589SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
590 size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800592 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594
Al Viro2903ff02012-08-28 12:52:22 -0400595 if (f.file) {
596 loff_t pos = file_pos_read(f.file);
597 ret = vfs_write(f.file, buf, count, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400598 if (ret >= 0)
599 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800600 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 }
602
603 return ret;
604}
605
Al Viro4a0fd5b2013-01-21 15:16:58 -0500606SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf,
607 size_t, count, loff_t, pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608{
Al Viro2903ff02012-08-28 12:52:22 -0400609 struct fd f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611
612 if (pos < 0)
613 return -EINVAL;
614
Al Viro2903ff02012-08-28 12:52:22 -0400615 f = fdget(fd);
616 if (f.file) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400618 if (f.file->f_mode & FMODE_PREAD)
619 ret = vfs_read(f.file, buf, count, &pos);
620 fdput(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 }
622
623 return ret;
624}
625
Al Viro4a0fd5b2013-01-21 15:16:58 -0500626SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf,
627 size_t, count, loff_t, pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628{
Al Viro2903ff02012-08-28 12:52:22 -0400629 struct fd f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631
632 if (pos < 0)
633 return -EINVAL;
634
Al Viro2903ff02012-08-28 12:52:22 -0400635 f = fdget(fd);
636 if (f.file) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400638 if (f.file->f_mode & FMODE_PWRITE)
639 ret = vfs_write(f.file, buf, count, &pos);
640 fdput(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 }
642
643 return ret;
644}
645
646/*
647 * Reduce an iovec's length in-place. Return the resulting number of segments
648 */
649unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to)
650{
651 unsigned long seg = 0;
652 size_t len = 0;
653
654 while (seg < nr_segs) {
655 seg++;
656 if (len + iov->iov_len >= to) {
657 iov->iov_len = to - len;
658 break;
659 }
660 len += iov->iov_len;
661 iov++;
662 }
663 return seg;
664}
Eric Sandeen19295522008-01-28 23:58:27 -0500665EXPORT_SYMBOL(iov_shorten);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666
Al Viro293bc982014-02-11 18:37:41 -0500667static ssize_t do_iter_readv_writev(struct file *filp, int rw, const struct iovec *iov,
668 unsigned long nr_segs, size_t len, loff_t *ppos, iter_fn_t fn)
669{
670 struct kiocb kiocb;
671 struct iov_iter iter;
672 ssize_t ret;
673
674 init_sync_kiocb(&kiocb, filp);
675 kiocb.ki_pos = *ppos;
676 kiocb.ki_nbytes = len;
677
678 iov_iter_init(&iter, rw, iov, nr_segs, len);
679 ret = fn(&kiocb, &iter);
680 if (ret == -EIOCBQUEUED)
681 ret = wait_on_sync_kiocb(&kiocb);
682 *ppos = kiocb.ki_pos;
683 return ret;
684}
685
Al Viro72ec3512013-03-20 10:42:10 -0400686static ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700687 unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn)
688{
689 struct kiocb kiocb;
690 ssize_t ret;
691
692 init_sync_kiocb(&kiocb, filp);
693 kiocb.ki_pos = *ppos;
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700694 kiocb.ki_nbytes = len;
695
Zach Brown41003a72013-05-07 16:18:25 -0700696 ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos);
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700697 if (ret == -EIOCBQUEUED)
698 ret = wait_on_sync_kiocb(&kiocb);
699 *ppos = kiocb.ki_pos;
700 return ret;
701}
702
703/* Do it by hand, with file-ops */
Al Viro72ec3512013-03-20 10:42:10 -0400704static ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700705 unsigned long nr_segs, loff_t *ppos, io_fn_t fn)
706{
707 struct iovec *vector = iov;
708 ssize_t ret = 0;
709
710 while (nr_segs > 0) {
711 void __user *base;
712 size_t len;
713 ssize_t nr;
714
715 base = vector->iov_base;
716 len = vector->iov_len;
717 vector++;
718 nr_segs--;
719
720 nr = fn(filp, base, len, ppos);
721
722 if (nr < 0) {
723 if (!ret)
724 ret = nr;
725 break;
726 }
727 ret += nr;
728 if (nr != len)
729 break;
730 }
731
732 return ret;
733}
734
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735/* A write operation does a read from user space and vice versa */
736#define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
737
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700738ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
739 unsigned long nr_segs, unsigned long fast_segs,
740 struct iovec *fast_pointer,
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700741 struct iovec **ret_pointer)
Linus Torvalds435f49a2010-10-29 10:36:49 -0700742{
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700743 unsigned long seg;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700744 ssize_t ret;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700745 struct iovec *iov = fast_pointer;
746
Linus Torvalds435f49a2010-10-29 10:36:49 -0700747 /*
748 * SuS says "The readv() function *may* fail if the iovcnt argument
749 * was less than or equal to 0, or greater than {IOV_MAX}. Linux has
750 * traditionally returned zero for zero segments, so...
751 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700752 if (nr_segs == 0) {
753 ret = 0;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700754 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700755 }
756
Linus Torvalds435f49a2010-10-29 10:36:49 -0700757 /*
758 * First get the "struct iovec" from user memory and
759 * verify all the pointers
760 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700761 if (nr_segs > UIO_MAXIOV) {
762 ret = -EINVAL;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700763 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700764 }
765 if (nr_segs > fast_segs) {
Linus Torvalds435f49a2010-10-29 10:36:49 -0700766 iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700767 if (iov == NULL) {
768 ret = -ENOMEM;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700769 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700770 }
Linus Torvalds435f49a2010-10-29 10:36:49 -0700771 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700772 if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) {
773 ret = -EFAULT;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700774 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700775 }
776
Linus Torvalds435f49a2010-10-29 10:36:49 -0700777 /*
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700778 * According to the Single Unix Specification we should return EINVAL
779 * if an element length is < 0 when cast to ssize_t or if the
780 * total length would overflow the ssize_t return value of the
781 * system call.
Linus Torvalds435f49a2010-10-29 10:36:49 -0700782 *
783 * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the
784 * overflow case.
785 */
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700786 ret = 0;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700787 for (seg = 0; seg < nr_segs; seg++) {
788 void __user *buf = iov[seg].iov_base;
789 ssize_t len = (ssize_t)iov[seg].iov_len;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700790
791 /* see if we we're about to use an invalid len or if
792 * it's about to overflow ssize_t */
Linus Torvalds435f49a2010-10-29 10:36:49 -0700793 if (len < 0) {
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700794 ret = -EINVAL;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700795 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700796 }
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700797 if (type >= 0
Christopher Yeohfcf63402011-10-31 17:06:39 -0700798 && unlikely(!access_ok(vrfy_dir(type), buf, len))) {
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700799 ret = -EFAULT;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700800 goto out;
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700801 }
Linus Torvalds435f49a2010-10-29 10:36:49 -0700802 if (len > MAX_RW_COUNT - ret) {
803 len = MAX_RW_COUNT - ret;
804 iov[seg].iov_len = len;
805 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700806 ret += len;
Linus Torvalds435f49a2010-10-29 10:36:49 -0700807 }
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700808out:
809 *ret_pointer = iov;
810 return ret;
811}
812
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813static ssize_t do_readv_writev(int type, struct file *file,
814 const struct iovec __user * uvector,
815 unsigned long nr_segs, loff_t *pos)
816{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 size_t tot_len;
818 struct iovec iovstack[UIO_FASTIOV];
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700819 struct iovec *iov = iovstack;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 ssize_t ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821 io_fn_t fn;
822 iov_fn_t fnv;
Al Viro293bc982014-02-11 18:37:41 -0500823 iter_fn_t iter_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700825 ret = rw_copy_check_uvector(type, uvector, nr_segs,
Christopher Yeohac34ebb2012-05-31 16:26:42 -0700826 ARRAY_SIZE(iovstack), iovstack, &iov);
Badari Pulavartyeed4e512006-09-30 23:28:49 -0700827 if (ret <= 0)
828 goto out;
829
830 tot_len = ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 ret = rw_verify_area(type, file, pos, tot_len);
Linus Torvaldse28cc712006-01-04 16:20:40 -0800832 if (ret < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 goto out;
834
835 fnv = NULL;
836 if (type == READ) {
837 fn = file->f_op->read;
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700838 fnv = file->f_op->aio_read;
Al Viro293bc982014-02-11 18:37:41 -0500839 iter_fn = file->f_op->read_iter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 } else {
841 fn = (io_fn_t)file->f_op->write;
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700842 fnv = file->f_op->aio_write;
Al Viro293bc982014-02-11 18:37:41 -0500843 iter_fn = file->f_op->write_iter;
Al Viro03d95eb2013-03-20 13:04:20 -0400844 file_start_write(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 }
846
Al Viro293bc982014-02-11 18:37:41 -0500847 if (iter_fn)
848 ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len,
849 pos, iter_fn);
850 else if (fnv)
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700851 ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
852 pos, fnv);
853 else
854 ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855
Al Viro03d95eb2013-03-20 13:04:20 -0400856 if (type != READ)
857 file_end_write(file);
858
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859out:
860 if (iov != iovstack)
861 kfree(iov);
Robert Love0eeca282005-07-12 17:06:03 -0400862 if ((ret + (type == READ)) > 0) {
863 if (type == READ)
Eric Paris2a12a9d2009-12-17 21:24:21 -0500864 fsnotify_access(file);
Robert Love0eeca282005-07-12 17:06:03 -0400865 else
Eric Paris2a12a9d2009-12-17 21:24:21 -0500866 fsnotify_modify(file);
Robert Love0eeca282005-07-12 17:06:03 -0400867 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869}
870
871ssize_t vfs_readv(struct file *file, const struct iovec __user *vec,
872 unsigned long vlen, loff_t *pos)
873{
874 if (!(file->f_mode & FMODE_READ))
875 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500876 if (!(file->f_mode & FMODE_CAN_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 return -EINVAL;
878
879 return do_readv_writev(READ, file, vec, vlen, pos);
880}
881
882EXPORT_SYMBOL(vfs_readv);
883
884ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
885 unsigned long vlen, loff_t *pos)
886{
887 if (!(file->f_mode & FMODE_WRITE))
888 return -EBADF;
Al Viro7f7f25e2014-02-11 17:49:24 -0500889 if (!(file->f_mode & FMODE_CAN_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890 return -EINVAL;
891
892 return do_readv_writev(WRITE, file, vec, vlen, pos);
893}
894
895EXPORT_SYMBOL(vfs_writev);
896
Heiko Carstens3cdad422009-01-14 14:14:22 +0100897SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec,
898 unsigned long, vlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700899{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800900 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902
Al Viro2903ff02012-08-28 12:52:22 -0400903 if (f.file) {
904 loff_t pos = file_pos_read(f.file);
905 ret = vfs_readv(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400906 if (ret >= 0)
907 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800908 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909 }
910
911 if (ret > 0)
Alexey Dobriyan4b98d112007-02-10 01:46:45 -0800912 add_rchar(current, ret);
913 inc_syscr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914 return ret;
915}
916
Heiko Carstens3cdad422009-01-14 14:14:22 +0100917SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec,
918 unsigned long, vlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919{
Linus Torvalds9c225f22014-03-03 09:36:58 -0800920 struct fd f = fdget_pos(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 ssize_t ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922
Al Viro2903ff02012-08-28 12:52:22 -0400923 if (f.file) {
924 loff_t pos = file_pos_read(f.file);
925 ret = vfs_writev(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +0400926 if (ret >= 0)
927 file_pos_write(f.file, pos);
Linus Torvalds9c225f22014-03-03 09:36:58 -0800928 fdput_pos(f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929 }
930
931 if (ret > 0)
Alexey Dobriyan4b98d112007-02-10 01:46:45 -0800932 add_wchar(current, ret);
933 inc_syscw(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700934 return ret;
935}
936
Linus Torvalds601cc112009-04-03 08:03:22 -0700937static inline loff_t pos_from_hilo(unsigned long high, unsigned long low)
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700938{
Linus Torvalds601cc112009-04-03 08:03:22 -0700939#define HALF_LONG_BITS (BITS_PER_LONG / 2)
940 return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low;
941}
942
943SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec,
944 unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
945{
946 loff_t pos = pos_from_hilo(pos_h, pos_l);
Al Viro2903ff02012-08-28 12:52:22 -0400947 struct fd f;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700948 ssize_t ret = -EBADF;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700949
950 if (pos < 0)
951 return -EINVAL;
952
Al Viro2903ff02012-08-28 12:52:22 -0400953 f = fdget(fd);
954 if (f.file) {
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700955 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400956 if (f.file->f_mode & FMODE_PREAD)
957 ret = vfs_readv(f.file, vec, vlen, &pos);
958 fdput(f);
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700959 }
960
961 if (ret > 0)
962 add_rchar(current, ret);
963 inc_syscr(current);
964 return ret;
965}
966
967SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec,
Linus Torvalds601cc112009-04-03 08:03:22 -0700968 unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h)
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700969{
Linus Torvalds601cc112009-04-03 08:03:22 -0700970 loff_t pos = pos_from_hilo(pos_h, pos_l);
Al Viro2903ff02012-08-28 12:52:22 -0400971 struct fd f;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700972 ssize_t ret = -EBADF;
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700973
974 if (pos < 0)
975 return -EINVAL;
976
Al Viro2903ff02012-08-28 12:52:22 -0400977 f = fdget(fd);
978 if (f.file) {
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700979 ret = -ESPIPE;
Al Viro2903ff02012-08-28 12:52:22 -0400980 if (f.file->f_mode & FMODE_PWRITE)
981 ret = vfs_writev(f.file, vec, vlen, &pos);
982 fdput(f);
Gerd Hoffmannf3554f42009-04-02 16:59:23 -0700983 }
984
985 if (ret > 0)
986 add_wchar(current, ret);
987 inc_syscw(current);
988 return ret;
989}
990
Al Viro72ec3512013-03-20 10:42:10 -0400991#ifdef CONFIG_COMPAT
992
993static ssize_t compat_do_readv_writev(int type, struct file *file,
994 const struct compat_iovec __user *uvector,
995 unsigned long nr_segs, loff_t *pos)
996{
997 compat_ssize_t tot_len;
998 struct iovec iovstack[UIO_FASTIOV];
999 struct iovec *iov = iovstack;
1000 ssize_t ret;
1001 io_fn_t fn;
1002 iov_fn_t fnv;
Al Viro293bc982014-02-11 18:37:41 -05001003 iter_fn_t iter_fn;
Al Viro72ec3512013-03-20 10:42:10 -04001004
Al Viro72ec3512013-03-20 10:42:10 -04001005 ret = compat_rw_copy_check_uvector(type, uvector, nr_segs,
1006 UIO_FASTIOV, iovstack, &iov);
1007 if (ret <= 0)
1008 goto out;
1009
1010 tot_len = ret;
1011 ret = rw_verify_area(type, file, pos, tot_len);
1012 if (ret < 0)
1013 goto out;
1014
1015 fnv = NULL;
1016 if (type == READ) {
1017 fn = file->f_op->read;
1018 fnv = file->f_op->aio_read;
Al Viro293bc982014-02-11 18:37:41 -05001019 iter_fn = file->f_op->read_iter;
Al Viro72ec3512013-03-20 10:42:10 -04001020 } else {
1021 fn = (io_fn_t)file->f_op->write;
1022 fnv = file->f_op->aio_write;
Al Viro293bc982014-02-11 18:37:41 -05001023 iter_fn = file->f_op->write_iter;
Al Viro03d95eb2013-03-20 13:04:20 -04001024 file_start_write(file);
Al Viro72ec3512013-03-20 10:42:10 -04001025 }
1026
Al Viro293bc982014-02-11 18:37:41 -05001027 if (iter_fn)
1028 ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len,
1029 pos, iter_fn);
1030 else if (fnv)
Al Viro72ec3512013-03-20 10:42:10 -04001031 ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
1032 pos, fnv);
Al Viro03d95eb2013-03-20 13:04:20 -04001033 else
Al Viro72ec3512013-03-20 10:42:10 -04001034 ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);
1035
Al Viro03d95eb2013-03-20 13:04:20 -04001036 if (type != READ)
1037 file_end_write(file);
1038
Al Viro72ec3512013-03-20 10:42:10 -04001039out:
1040 if (iov != iovstack)
1041 kfree(iov);
1042 if ((ret + (type == READ)) > 0) {
1043 if (type == READ)
1044 fsnotify_access(file);
1045 else
1046 fsnotify_modify(file);
1047 }
1048 return ret;
1049}
1050
1051static size_t compat_readv(struct file *file,
1052 const struct compat_iovec __user *vec,
1053 unsigned long vlen, loff_t *pos)
1054{
1055 ssize_t ret = -EBADF;
1056
1057 if (!(file->f_mode & FMODE_READ))
1058 goto out;
1059
1060 ret = -EINVAL;
Al Viro7f7f25e2014-02-11 17:49:24 -05001061 if (!(file->f_mode & FMODE_CAN_READ))
Al Viro72ec3512013-03-20 10:42:10 -04001062 goto out;
1063
1064 ret = compat_do_readv_writev(READ, file, vec, vlen, pos);
1065
1066out:
1067 if (ret > 0)
1068 add_rchar(current, ret);
1069 inc_syscr(current);
1070 return ret;
1071}
1072
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001073COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001074 const struct compat_iovec __user *,vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001075 compat_ulong_t, vlen)
Al Viro72ec3512013-03-20 10:42:10 -04001076{
Linus Torvalds9c225f22014-03-03 09:36:58 -08001077 struct fd f = fdget_pos(fd);
Al Viro72ec3512013-03-20 10:42:10 -04001078 ssize_t ret;
1079 loff_t pos;
1080
1081 if (!f.file)
1082 return -EBADF;
1083 pos = f.file->f_pos;
1084 ret = compat_readv(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +04001085 if (ret >= 0)
1086 f.file->f_pos = pos;
Linus Torvalds9c225f22014-03-03 09:36:58 -08001087 fdput_pos(f);
Al Viro72ec3512013-03-20 10:42:10 -04001088 return ret;
1089}
1090
Heiko Carstens378a10f2014-03-05 10:43:51 +01001091static long __compat_sys_preadv64(unsigned long fd,
1092 const struct compat_iovec __user *vec,
1093 unsigned long vlen, loff_t pos)
Al Viro72ec3512013-03-20 10:42:10 -04001094{
1095 struct fd f;
1096 ssize_t ret;
1097
1098 if (pos < 0)
1099 return -EINVAL;
1100 f = fdget(fd);
1101 if (!f.file)
1102 return -EBADF;
1103 ret = -ESPIPE;
1104 if (f.file->f_mode & FMODE_PREAD)
1105 ret = compat_readv(f.file, vec, vlen, &pos);
1106 fdput(f);
1107 return ret;
1108}
1109
Heiko Carstens378a10f2014-03-05 10:43:51 +01001110#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64
1111COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd,
1112 const struct compat_iovec __user *,vec,
1113 unsigned long, vlen, loff_t, pos)
1114{
1115 return __compat_sys_preadv64(fd, vec, vlen, pos);
1116}
1117#endif
1118
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001119COMPAT_SYSCALL_DEFINE5(preadv, 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, u32, pos_low, u32, pos_high)
Al Viro72ec3512013-03-20 10:42:10 -04001122{
1123 loff_t pos = ((loff_t)pos_high << 32) | pos_low;
Heiko Carstens378a10f2014-03-05 10:43:51 +01001124
1125 return __compat_sys_preadv64(fd, vec, vlen, pos);
Al Viro72ec3512013-03-20 10:42:10 -04001126}
1127
1128static size_t compat_writev(struct file *file,
1129 const struct compat_iovec __user *vec,
1130 unsigned long vlen, loff_t *pos)
1131{
1132 ssize_t ret = -EBADF;
1133
1134 if (!(file->f_mode & FMODE_WRITE))
1135 goto out;
1136
1137 ret = -EINVAL;
Al Viro7f7f25e2014-02-11 17:49:24 -05001138 if (!(file->f_mode & FMODE_CAN_WRITE))
Al Viro72ec3512013-03-20 10:42:10 -04001139 goto out;
1140
1141 ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos);
1142
1143out:
1144 if (ret > 0)
1145 add_wchar(current, ret);
1146 inc_syscw(current);
1147 return ret;
1148}
1149
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001150COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd,
Al Viro72ec3512013-03-20 10:42:10 -04001151 const struct compat_iovec __user *, vec,
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001152 compat_ulong_t, vlen)
Al Viro72ec3512013-03-20 10:42:10 -04001153{
Linus Torvalds9c225f22014-03-03 09:36:58 -08001154 struct fd f = fdget_pos(fd);
Al Viro72ec3512013-03-20 10:42:10 -04001155 ssize_t ret;
1156 loff_t pos;
1157
1158 if (!f.file)
1159 return -EBADF;
1160 pos = f.file->f_pos;
1161 ret = compat_writev(f.file, vec, vlen, &pos);
Al Viro5faf1532013-06-15 05:49:36 +04001162 if (ret >= 0)
1163 f.file->f_pos = pos;
Linus Torvalds9c225f22014-03-03 09:36:58 -08001164 fdput_pos(f);
Al Viro72ec3512013-03-20 10:42:10 -04001165 return ret;
1166}
1167
Heiko Carstens378a10f2014-03-05 10:43:51 +01001168static long __compat_sys_pwritev64(unsigned long fd,
1169 const struct compat_iovec __user *vec,
1170 unsigned long vlen, loff_t pos)
Al Viro72ec3512013-03-20 10:42:10 -04001171{
1172 struct fd f;
1173 ssize_t ret;
1174
1175 if (pos < 0)
1176 return -EINVAL;
1177 f = fdget(fd);
1178 if (!f.file)
1179 return -EBADF;
1180 ret = -ESPIPE;
1181 if (f.file->f_mode & FMODE_PWRITE)
1182 ret = compat_writev(f.file, vec, vlen, &pos);
1183 fdput(f);
1184 return ret;
1185}
1186
Heiko Carstens378a10f2014-03-05 10:43:51 +01001187#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64
1188COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd,
1189 const struct compat_iovec __user *,vec,
1190 unsigned long, vlen, loff_t, pos)
1191{
1192 return __compat_sys_pwritev64(fd, vec, vlen, pos);
1193}
1194#endif
1195
Heiko Carstensdfd948e2014-01-29 14:05:44 -08001196COMPAT_SYSCALL_DEFINE5(pwritev, 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, u32, pos_low, u32, pos_high)
Al Viro72ec3512013-03-20 10:42:10 -04001199{
1200 loff_t pos = ((loff_t)pos_high << 32) | pos_low;
Heiko Carstens378a10f2014-03-05 10:43:51 +01001201
1202 return __compat_sys_pwritev64(fd, vec, vlen, pos);
Al Viro72ec3512013-03-20 10:42:10 -04001203}
1204#endif
1205
Al Viro19f4fc32013-02-24 02:17:03 -05001206static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
1207 size_t count, loff_t max)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208{
Al Viro2903ff02012-08-28 12:52:22 -04001209 struct fd in, out;
1210 struct inode *in_inode, *out_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001211 loff_t pos;
Al Viro7995bd22013-06-20 18:58:36 +04001212 loff_t out_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001213 ssize_t retval;
Al Viro2903ff02012-08-28 12:52:22 -04001214 int fl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001215
1216 /*
1217 * Get input file, and verify that it is ok..
1218 */
1219 retval = -EBADF;
Al Viro2903ff02012-08-28 12:52:22 -04001220 in = fdget(in_fd);
1221 if (!in.file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001222 goto out;
Al Viro2903ff02012-08-28 12:52:22 -04001223 if (!(in.file->f_mode & FMODE_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224 goto fput_in;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225 retval = -ESPIPE;
Al Viro7995bd22013-06-20 18:58:36 +04001226 if (!ppos) {
1227 pos = in.file->f_pos;
1228 } else {
1229 pos = *ppos;
Al Viro2903ff02012-08-28 12:52:22 -04001230 if (!(in.file->f_mode & FMODE_PREAD))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231 goto fput_in;
Al Viro7995bd22013-06-20 18:58:36 +04001232 }
1233 retval = rw_verify_area(READ, in.file, &pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -08001234 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001235 goto fput_in;
Linus Torvaldse28cc712006-01-04 16:20:40 -08001236 count = retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001237
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 /*
1239 * Get output file, and verify that it is ok..
1240 */
1241 retval = -EBADF;
Al Viro2903ff02012-08-28 12:52:22 -04001242 out = fdget(out_fd);
1243 if (!out.file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001244 goto fput_in;
Al Viro2903ff02012-08-28 12:52:22 -04001245 if (!(out.file->f_mode & FMODE_WRITE))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001246 goto fput_out;
1247 retval = -EINVAL;
Al Viro496ad9a2013-01-23 17:07:38 -05001248 in_inode = file_inode(in.file);
1249 out_inode = file_inode(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001250 out_pos = out.file->f_pos;
1251 retval = rw_verify_area(WRITE, out.file, &out_pos, count);
Linus Torvaldse28cc712006-01-04 16:20:40 -08001252 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001253 goto fput_out;
Linus Torvaldse28cc712006-01-04 16:20:40 -08001254 count = retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001255
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256 if (!max)
1257 max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
1258
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259 if (unlikely(pos + count > max)) {
1260 retval = -EOVERFLOW;
1261 if (pos >= max)
1262 goto fput_out;
1263 count = max - pos;
1264 }
1265
Jens Axboed96e6e72007-06-11 12:18:52 +02001266 fl = 0;
Jens Axboe534f2aa2007-06-01 14:52:37 +02001267#if 0
Jens Axboed96e6e72007-06-11 12:18:52 +02001268 /*
1269 * We need to debate whether we can enable this or not. The
1270 * man page documents EAGAIN return for the output at least,
1271 * and the application is arguably buggy if it doesn't expect
1272 * EAGAIN on a non-blocking file descriptor.
1273 */
Al Viro2903ff02012-08-28 12:52:22 -04001274 if (in.file->f_flags & O_NONBLOCK)
Jens Axboed96e6e72007-06-11 12:18:52 +02001275 fl = SPLICE_F_NONBLOCK;
Jens Axboe534f2aa2007-06-01 14:52:37 +02001276#endif
Al Viro50cd2c52013-05-23 20:10:34 -04001277 file_start_write(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001278 retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl);
Al Viro50cd2c52013-05-23 20:10:34 -04001279 file_end_write(out.file);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280
1281 if (retval > 0) {
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001282 add_rchar(current, retval);
1283 add_wchar(current, retval);
Scott Wolchoka68c2f12012-12-20 15:05:52 -08001284 fsnotify_access(in.file);
1285 fsnotify_modify(out.file);
Al Viro7995bd22013-06-20 18:58:36 +04001286 out.file->f_pos = out_pos;
1287 if (ppos)
1288 *ppos = pos;
1289 else
1290 in.file->f_pos = pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001293 inc_syscr(current);
1294 inc_syscw(current);
Al Viro7995bd22013-06-20 18:58:36 +04001295 if (pos > max)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 retval = -EOVERFLOW;
1297
1298fput_out:
Al Viro2903ff02012-08-28 12:52:22 -04001299 fdput(out);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001300fput_in:
Al Viro2903ff02012-08-28 12:52:22 -04001301 fdput(in);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001302out:
1303 return retval;
1304}
1305
Heiko Carstens002c8972009-01-14 14:14:18 +01001306SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001307{
1308 loff_t pos;
1309 off_t off;
1310 ssize_t ret;
1311
1312 if (offset) {
1313 if (unlikely(get_user(off, offset)))
1314 return -EFAULT;
1315 pos = off;
1316 ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
1317 if (unlikely(put_user(pos, offset)))
1318 return -EFAULT;
1319 return ret;
1320 }
1321
1322 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1323}
1324
Heiko Carstens002c8972009-01-14 14:14:18 +01001325SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001326{
1327 loff_t pos;
1328 ssize_t ret;
1329
1330 if (offset) {
1331 if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
1332 return -EFAULT;
1333 ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
1334 if (unlikely(put_user(pos, offset)))
1335 return -EFAULT;
1336 return ret;
1337 }
1338
1339 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1340}
Al Viro19f4fc32013-02-24 02:17:03 -05001341
1342#ifdef CONFIG_COMPAT
1343COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd,
1344 compat_off_t __user *, offset, compat_size_t, count)
1345{
1346 loff_t pos;
1347 off_t off;
1348 ssize_t ret;
1349
1350 if (offset) {
1351 if (unlikely(get_user(off, offset)))
1352 return -EFAULT;
1353 pos = off;
1354 ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
1355 if (unlikely(put_user(pos, offset)))
1356 return -EFAULT;
1357 return ret;
1358 }
1359
1360 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1361}
1362
1363COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd,
1364 compat_loff_t __user *, offset, compat_size_t, count)
1365{
1366 loff_t pos;
1367 ssize_t ret;
1368
1369 if (offset) {
1370 if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
1371 return -EFAULT;
1372 ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
1373 if (unlikely(put_user(pos, offset)))
1374 return -EFAULT;
1375 return ret;
1376 }
1377
1378 return do_sendfile(out_fd, in_fd, NULL, count, 0);
1379}
1380#endif