2 * linux/fs/read_write.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
7 #include <linux/slab.h>
8 #include <linux/stat.h>
9 #include <linux/fcntl.h>
10 #include <linux/file.h>
11 #include <linux/uio.h>
12 #include <linux/fsnotify.h>
13 #include <linux/security.h>
14 #include <linux/export.h>
15 #include <linux/syscalls.h>
16 #include <linux/pagemap.h>
17 #include <linux/splice.h>
18 #include <linux/compat.h>
21 #include <asm/uaccess.h>
22 #include <asm/unistd.h>
24 typedef ssize_t (*io_fn_t
)(struct file
*, char __user
*, size_t, loff_t
*);
25 typedef ssize_t (*iter_fn_t
)(struct kiocb
*, struct iov_iter
*);
27 const struct file_operations generic_ro_fops
= {
28 .llseek
= generic_file_llseek
,
29 .read_iter
= generic_file_read_iter
,
30 .mmap
= generic_file_readonly_mmap
,
31 .splice_read
= generic_file_splice_read
,
34 EXPORT_SYMBOL(generic_ro_fops
);
36 static inline int unsigned_offsets(struct file
*file
)
38 return file
->f_mode
& FMODE_UNSIGNED_OFFSET
;
42 * vfs_setpos - update the file offset for lseek
43 * @file: file structure in question
44 * @offset: file offset to seek to
45 * @maxsize: maximum file size
47 * This is a low-level filesystem helper for updating the file offset to
48 * the value specified by @offset if the given offset is valid and it is
49 * not equal to the current file offset.
51 * Return the specified offset on success and -EINVAL on invalid offset.
53 loff_t
vfs_setpos(struct file
*file
, loff_t offset
, loff_t maxsize
)
55 if (offset
< 0 && !unsigned_offsets(file
))
60 if (offset
!= file
->f_pos
) {
66 EXPORT_SYMBOL(vfs_setpos
);
69 * generic_file_llseek_size - generic llseek implementation for regular files
70 * @file: file structure to seek on
71 * @offset: file offset to seek to
72 * @whence: type of seek
73 * @size: max size of this file in file system
74 * @eof: offset used for SEEK_END position
76 * This is a variant of generic_file_llseek that allows passing in a custom
77 * maximum file size and a custom EOF position, for e.g. hashed directories
80 * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms)
81 * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes.
82 * read/writes behave like SEEK_SET against seeks.
85 generic_file_llseek_size(struct file
*file
, loff_t offset
, int whence
,
86 loff_t maxsize
, loff_t eof
)
94 * Here we special-case the lseek(fd, 0, SEEK_CUR)
95 * position-querying operation. Avoid rewriting the "same"
96 * f_pos value back to the file because a concurrent read(),
97 * write() or lseek() might have altered it
102 * f_lock protects against read/modify/write race with other
103 * SEEK_CURs. Note that parallel writes and reads behave
106 spin_lock(&file
->f_lock
);
107 offset
= vfs_setpos(file
, file
->f_pos
+ offset
, maxsize
);
108 spin_unlock(&file
->f_lock
);
112 * In the generic case the entire file is data, so as long as
113 * offset isn't at the end of the file then the offset is data.
115 if ((unsigned long long)offset
>= eof
)
120 * There is a virtual hole at the end of the file, so as long as
121 * offset isn't i_size or larger, return i_size.
123 if ((unsigned long long)offset
>= eof
)
129 return vfs_setpos(file
, offset
, maxsize
);
131 EXPORT_SYMBOL(generic_file_llseek_size
);
134 * generic_file_llseek - generic llseek implementation for regular files
135 * @file: file structure to seek on
136 * @offset: file offset to seek to
137 * @whence: type of seek
139 * This is a generic implemenation of ->llseek useable for all normal local
140 * filesystems. It just updates the file offset to the value specified by
141 * @offset and @whence.
143 loff_t
generic_file_llseek(struct file
*file
, loff_t offset
, int whence
)
145 struct inode
*inode
= file
->f_mapping
->host
;
147 return generic_file_llseek_size(file
, offset
, whence
,
148 inode
->i_sb
->s_maxbytes
,
151 EXPORT_SYMBOL(generic_file_llseek
);
154 * fixed_size_llseek - llseek implementation for fixed-sized devices
155 * @file: file structure to seek on
156 * @offset: file offset to seek to
157 * @whence: type of seek
158 * @size: size of the file
161 loff_t
fixed_size_llseek(struct file
*file
, loff_t offset
, int whence
, loff_t size
)
164 case SEEK_SET
: case SEEK_CUR
: case SEEK_END
:
165 return generic_file_llseek_size(file
, offset
, whence
,
171 EXPORT_SYMBOL(fixed_size_llseek
);
174 * noop_llseek - No Operation Performed llseek implementation
175 * @file: file structure to seek on
176 * @offset: file offset to seek to
177 * @whence: type of seek
179 * This is an implementation of ->llseek useable for the rare special case when
180 * userspace expects the seek to succeed but the (device) file is actually not
181 * able to perform the seek. In this case you use noop_llseek() instead of
182 * falling back to the default implementation of ->llseek.
184 loff_t
noop_llseek(struct file
*file
, loff_t offset
, int whence
)
188 EXPORT_SYMBOL(noop_llseek
);
190 loff_t
no_llseek(struct file
*file
, loff_t offset
, int whence
)
194 EXPORT_SYMBOL(no_llseek
);
196 loff_t
default_llseek(struct file
*file
, loff_t offset
, int whence
)
198 struct inode
*inode
= file_inode(file
);
201 mutex_lock(&inode
->i_mutex
);
204 offset
+= i_size_read(inode
);
208 retval
= file
->f_pos
;
211 offset
+= file
->f_pos
;
215 * In the generic case the entire file is data, so as
216 * long as offset isn't at the end of the file then the
219 if (offset
>= inode
->i_size
) {
226 * There is a virtual hole at the end of the file, so
227 * as long as offset isn't i_size or larger, return
230 if (offset
>= inode
->i_size
) {
234 offset
= inode
->i_size
;
238 if (offset
>= 0 || unsigned_offsets(file
)) {
239 if (offset
!= file
->f_pos
) {
240 file
->f_pos
= offset
;
246 mutex_unlock(&inode
->i_mutex
);
249 EXPORT_SYMBOL(default_llseek
);
251 loff_t
vfs_llseek(struct file
*file
, loff_t offset
, int whence
)
253 loff_t (*fn
)(struct file
*, loff_t
, int);
256 if (file
->f_mode
& FMODE_LSEEK
) {
257 if (file
->f_op
->llseek
)
258 fn
= file
->f_op
->llseek
;
260 return fn(file
, offset
, whence
);
262 EXPORT_SYMBOL(vfs_llseek
);
264 static inline struct fd
fdget_pos(int fd
)
266 return __to_fd(__fdget_pos(fd
));
269 static inline void fdput_pos(struct fd f
)
271 if (f
.flags
& FDPUT_POS_UNLOCK
)
272 mutex_unlock(&f
.file
->f_pos_lock
);
276 SYSCALL_DEFINE3(lseek
, unsigned int, fd
, off_t
, offset
, unsigned int, whence
)
279 struct fd f
= fdget_pos(fd
);
284 if (whence
<= SEEK_MAX
) {
285 loff_t res
= vfs_llseek(f
.file
, offset
, whence
);
287 if (res
!= (loff_t
)retval
)
288 retval
= -EOVERFLOW
; /* LFS: should only happen on 32 bit platforms */
295 COMPAT_SYSCALL_DEFINE3(lseek
, unsigned int, fd
, compat_off_t
, offset
, unsigned int, whence
)
297 return sys_lseek(fd
, offset
, whence
);
301 #ifdef __ARCH_WANT_SYS_LLSEEK
302 SYSCALL_DEFINE5(llseek
, unsigned int, fd
, unsigned long, offset_high
,
303 unsigned long, offset_low
, loff_t __user
*, result
,
304 unsigned int, whence
)
307 struct fd f
= fdget_pos(fd
);
314 if (whence
> SEEK_MAX
)
317 offset
= vfs_llseek(f
.file
, ((loff_t
) offset_high
<< 32) | offset_low
,
320 retval
= (int)offset
;
323 if (!copy_to_user(result
, &offset
, sizeof(offset
)))
332 ssize_t
vfs_iter_read(struct file
*file
, struct iov_iter
*iter
, loff_t
*ppos
)
337 if (!file
->f_op
->read_iter
)
340 init_sync_kiocb(&kiocb
, file
);
341 kiocb
.ki_pos
= *ppos
;
344 ret
= file
->f_op
->read_iter(&kiocb
, iter
);
345 BUG_ON(ret
== -EIOCBQUEUED
);
347 *ppos
= kiocb
.ki_pos
;
350 EXPORT_SYMBOL(vfs_iter_read
);
352 ssize_t
vfs_iter_write(struct file
*file
, struct iov_iter
*iter
, loff_t
*ppos
)
357 if (!file
->f_op
->write_iter
)
360 init_sync_kiocb(&kiocb
, file
);
361 kiocb
.ki_pos
= *ppos
;
364 ret
= file
->f_op
->write_iter(&kiocb
, iter
);
365 BUG_ON(ret
== -EIOCBQUEUED
);
367 *ppos
= kiocb
.ki_pos
;
370 EXPORT_SYMBOL(vfs_iter_write
);
373 * rw_verify_area doesn't like huge counts. We limit
374 * them to something that fits in "int" so that others
375 * won't have to do range checks all the time.
377 int rw_verify_area(int read_write
, struct file
*file
, const loff_t
*ppos
, size_t count
)
381 int retval
= -EINVAL
;
383 inode
= file_inode(file
);
384 if (unlikely((ssize_t
) count
< 0))
387 if (unlikely(pos
< 0)) {
388 if (!unsigned_offsets(file
))
390 if (count
>= -pos
) /* both values are in 0..LLONG_MAX */
392 } else if (unlikely((loff_t
) (pos
+ count
) < 0)) {
393 if (!unsigned_offsets(file
))
397 if (unlikely(inode
->i_flctx
&& mandatory_lock(inode
))) {
398 retval
= locks_mandatory_area(
399 read_write
== READ
? FLOCK_VERIFY_READ
: FLOCK_VERIFY_WRITE
,
400 inode
, file
, pos
, count
);
404 retval
= security_file_permission(file
,
405 read_write
== READ
? MAY_READ
: MAY_WRITE
);
408 return count
> MAX_RW_COUNT
? MAX_RW_COUNT
: count
;
411 static ssize_t
new_sync_read(struct file
*filp
, char __user
*buf
, size_t len
, loff_t
*ppos
)
413 struct iovec iov
= { .iov_base
= buf
, .iov_len
= len
};
415 struct iov_iter iter
;
418 init_sync_kiocb(&kiocb
, filp
);
419 kiocb
.ki_pos
= *ppos
;
420 iov_iter_init(&iter
, READ
, &iov
, 1, len
);
422 ret
= filp
->f_op
->read_iter(&kiocb
, &iter
);
423 BUG_ON(ret
== -EIOCBQUEUED
);
424 *ppos
= kiocb
.ki_pos
;
428 ssize_t
__vfs_read(struct file
*file
, char __user
*buf
, size_t count
,
431 if (file
->f_op
->read
)
432 return file
->f_op
->read(file
, buf
, count
, pos
);
433 else if (file
->f_op
->read_iter
)
434 return new_sync_read(file
, buf
, count
, pos
);
438 EXPORT_SYMBOL(__vfs_read
);
440 ssize_t
vfs_read(struct file
*file
, char __user
*buf
, size_t count
, loff_t
*pos
)
444 if (!(file
->f_mode
& FMODE_READ
))
446 if (!(file
->f_mode
& FMODE_CAN_READ
))
448 if (unlikely(!access_ok(VERIFY_WRITE
, buf
, count
)))
451 ret
= rw_verify_area(READ
, file
, pos
, count
);
454 ret
= __vfs_read(file
, buf
, count
, pos
);
456 fsnotify_access(file
);
457 add_rchar(current
, ret
);
465 EXPORT_SYMBOL(vfs_read
);
467 static ssize_t
new_sync_write(struct file
*filp
, const char __user
*buf
, size_t len
, loff_t
*ppos
)
469 struct iovec iov
= { .iov_base
= (void __user
*)buf
, .iov_len
= len
};
471 struct iov_iter iter
;
474 init_sync_kiocb(&kiocb
, filp
);
475 kiocb
.ki_pos
= *ppos
;
476 iov_iter_init(&iter
, WRITE
, &iov
, 1, len
);
478 ret
= filp
->f_op
->write_iter(&kiocb
, &iter
);
479 BUG_ON(ret
== -EIOCBQUEUED
);
481 *ppos
= kiocb
.ki_pos
;
485 ssize_t
__vfs_write(struct file
*file
, const char __user
*p
, size_t count
,
488 if (file
->f_op
->write
)
489 return file
->f_op
->write(file
, p
, count
, pos
);
490 else if (file
->f_op
->write_iter
)
491 return new_sync_write(file
, p
, count
, pos
);
495 EXPORT_SYMBOL(__vfs_write
);
497 vfs_readf_t
vfs_readf(struct file
*file
)
499 const struct file_operations
*fop
= file
->f_op
;
504 return new_sync_read
;
505 return ERR_PTR(-ENOSYS
);
507 EXPORT_SYMBOL(vfs_readf
);
509 vfs_writef_t
vfs_writef(struct file
*file
)
511 const struct file_operations
*fop
= file
->f_op
;
516 return new_sync_write
;
517 return ERR_PTR(-ENOSYS
);
519 EXPORT_SYMBOL(vfs_writef
);
521 ssize_t
__kernel_write(struct file
*file
, const char *buf
, size_t count
, loff_t
*pos
)
524 const char __user
*p
;
527 if (!(file
->f_mode
& FMODE_CAN_WRITE
))
532 p
= (__force
const char __user
*)buf
;
533 if (count
> MAX_RW_COUNT
)
534 count
= MAX_RW_COUNT
;
535 ret
= __vfs_write(file
, p
, count
, pos
);
538 fsnotify_modify(file
);
539 add_wchar(current
, ret
);
545 EXPORT_SYMBOL(__kernel_write
);
547 ssize_t
vfs_write(struct file
*file
, const char __user
*buf
, size_t count
, loff_t
*pos
)
551 if (!(file
->f_mode
& FMODE_WRITE
))
553 if (!(file
->f_mode
& FMODE_CAN_WRITE
))
555 if (unlikely(!access_ok(VERIFY_READ
, buf
, count
)))
558 ret
= rw_verify_area(WRITE
, file
, pos
, count
);
561 file_start_write(file
);
562 ret
= __vfs_write(file
, buf
, count
, pos
);
564 fsnotify_modify(file
);
565 add_wchar(current
, ret
);
568 file_end_write(file
);
574 EXPORT_SYMBOL(vfs_write
);
576 static inline loff_t
file_pos_read(struct file
*file
)
581 static inline void file_pos_write(struct file
*file
, loff_t pos
)
586 SYSCALL_DEFINE3(read
, unsigned int, fd
, char __user
*, buf
, size_t, count
)
588 struct fd f
= fdget_pos(fd
);
589 ssize_t ret
= -EBADF
;
592 loff_t pos
= file_pos_read(f
.file
);
593 ret
= vfs_read(f
.file
, buf
, count
, &pos
);
595 file_pos_write(f
.file
, pos
);
601 SYSCALL_DEFINE3(write
, unsigned int, fd
, const char __user
*, buf
,
604 struct fd f
= fdget_pos(fd
);
605 ssize_t ret
= -EBADF
;
608 loff_t pos
= file_pos_read(f
.file
);
609 ret
= vfs_write(f
.file
, buf
, count
, &pos
);
611 file_pos_write(f
.file
, pos
);
618 SYSCALL_DEFINE4(pread64
, unsigned int, fd
, char __user
*, buf
,
619 size_t, count
, loff_t
, pos
)
622 ssize_t ret
= -EBADF
;
630 if (f
.file
->f_mode
& FMODE_PREAD
)
631 ret
= vfs_read(f
.file
, buf
, count
, &pos
);
638 SYSCALL_DEFINE4(pwrite64
, unsigned int, fd
, const char __user
*, buf
,
639 size_t, count
, loff_t
, pos
)
642 ssize_t ret
= -EBADF
;
650 if (f
.file
->f_mode
& FMODE_PWRITE
)
651 ret
= vfs_write(f
.file
, buf
, count
, &pos
);
659 * Reduce an iovec's length in-place. Return the resulting number of segments
661 unsigned long iov_shorten(struct iovec
*iov
, unsigned long nr_segs
, size_t to
)
663 unsigned long seg
= 0;
666 while (seg
< nr_segs
) {
668 if (len
+ iov
->iov_len
>= to
) {
669 iov
->iov_len
= to
- len
;
677 EXPORT_SYMBOL(iov_shorten
);
679 static ssize_t
do_iter_readv_writev(struct file
*filp
, struct iov_iter
*iter
,
680 loff_t
*ppos
, iter_fn_t fn
)
685 init_sync_kiocb(&kiocb
, filp
);
686 kiocb
.ki_pos
= *ppos
;
688 ret
= fn(&kiocb
, iter
);
689 BUG_ON(ret
== -EIOCBQUEUED
);
690 *ppos
= kiocb
.ki_pos
;
694 /* Do it by hand, with file-ops */
695 static ssize_t
do_loop_readv_writev(struct file
*filp
, struct iov_iter
*iter
,
696 loff_t
*ppos
, io_fn_t fn
)
700 while (iov_iter_count(iter
)) {
701 struct iovec iovec
= iov_iter_iovec(iter
);
704 nr
= fn(filp
, iovec
.iov_base
, iovec
.iov_len
, ppos
);
712 if (nr
!= iovec
.iov_len
)
714 iov_iter_advance(iter
, nr
);
720 /* A write operation does a read from user space and vice versa */
721 #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
723 ssize_t
rw_copy_check_uvector(int type
, const struct iovec __user
* uvector
,
724 unsigned long nr_segs
, unsigned long fast_segs
,
725 struct iovec
*fast_pointer
,
726 struct iovec
**ret_pointer
)
730 struct iovec
*iov
= fast_pointer
;
733 * SuS says "The readv() function *may* fail if the iovcnt argument
734 * was less than or equal to 0, or greater than {IOV_MAX}. Linux has
735 * traditionally returned zero for zero segments, so...
743 * First get the "struct iovec" from user memory and
744 * verify all the pointers
746 if (nr_segs
> UIO_MAXIOV
) {
750 if (nr_segs
> fast_segs
) {
751 iov
= kmalloc(nr_segs
*sizeof(struct iovec
), GFP_KERNEL
);
757 if (copy_from_user(iov
, uvector
, nr_segs
*sizeof(*uvector
))) {
763 * According to the Single Unix Specification we should return EINVAL
764 * if an element length is < 0 when cast to ssize_t or if the
765 * total length would overflow the ssize_t return value of the
768 * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the
772 for (seg
= 0; seg
< nr_segs
; seg
++) {
773 void __user
*buf
= iov
[seg
].iov_base
;
774 ssize_t len
= (ssize_t
)iov
[seg
].iov_len
;
776 /* see if we we're about to use an invalid len or if
777 * it's about to overflow ssize_t */
783 && unlikely(!access_ok(vrfy_dir(type
), buf
, len
))) {
787 if (len
> MAX_RW_COUNT
- ret
) {
788 len
= MAX_RW_COUNT
- ret
;
789 iov
[seg
].iov_len
= len
;
798 static ssize_t
do_readv_writev(int type
, struct file
*file
,
799 const struct iovec __user
* uvector
,
800 unsigned long nr_segs
, loff_t
*pos
)
803 struct iovec iovstack
[UIO_FASTIOV
];
804 struct iovec
*iov
= iovstack
;
805 struct iov_iter iter
;
810 ret
= import_iovec(type
, uvector
, nr_segs
,
811 ARRAY_SIZE(iovstack
), &iov
, &iter
);
815 tot_len
= iov_iter_count(&iter
);
818 ret
= rw_verify_area(type
, file
, pos
, tot_len
);
823 fn
= file
->f_op
->read
;
824 iter_fn
= file
->f_op
->read_iter
;
826 fn
= (io_fn_t
)file
->f_op
->write
;
827 iter_fn
= file
->f_op
->write_iter
;
828 file_start_write(file
);
832 ret
= do_iter_readv_writev(file
, &iter
, pos
, iter_fn
);
834 ret
= do_loop_readv_writev(file
, &iter
, pos
, fn
);
837 file_end_write(file
);
841 if ((ret
+ (type
== READ
)) > 0) {
843 fsnotify_access(file
);
845 fsnotify_modify(file
);
850 ssize_t
vfs_readv(struct file
*file
, const struct iovec __user
*vec
,
851 unsigned long vlen
, loff_t
*pos
)
853 if (!(file
->f_mode
& FMODE_READ
))
855 if (!(file
->f_mode
& FMODE_CAN_READ
))
858 return do_readv_writev(READ
, file
, vec
, vlen
, pos
);
861 EXPORT_SYMBOL(vfs_readv
);
863 ssize_t
vfs_writev(struct file
*file
, const struct iovec __user
*vec
,
864 unsigned long vlen
, loff_t
*pos
)
866 if (!(file
->f_mode
& FMODE_WRITE
))
868 if (!(file
->f_mode
& FMODE_CAN_WRITE
))
871 return do_readv_writev(WRITE
, file
, vec
, vlen
, pos
);
874 EXPORT_SYMBOL(vfs_writev
);
876 SYSCALL_DEFINE3(readv
, unsigned long, fd
, const struct iovec __user
*, vec
,
879 struct fd f
= fdget_pos(fd
);
880 ssize_t ret
= -EBADF
;
883 loff_t pos
= file_pos_read(f
.file
);
884 ret
= vfs_readv(f
.file
, vec
, vlen
, &pos
);
886 file_pos_write(f
.file
, pos
);
891 add_rchar(current
, ret
);
896 SYSCALL_DEFINE3(writev
, unsigned long, fd
, const struct iovec __user
*, vec
,
899 struct fd f
= fdget_pos(fd
);
900 ssize_t ret
= -EBADF
;
903 loff_t pos
= file_pos_read(f
.file
);
904 ret
= vfs_writev(f
.file
, vec
, vlen
, &pos
);
906 file_pos_write(f
.file
, pos
);
911 add_wchar(current
, ret
);
916 static inline loff_t
pos_from_hilo(unsigned long high
, unsigned long low
)
918 #define HALF_LONG_BITS (BITS_PER_LONG / 2)
919 return (((loff_t
)high
<< HALF_LONG_BITS
) << HALF_LONG_BITS
) | low
;
922 SYSCALL_DEFINE5(preadv
, unsigned long, fd
, const struct iovec __user
*, vec
,
923 unsigned long, vlen
, unsigned long, pos_l
, unsigned long, pos_h
)
925 loff_t pos
= pos_from_hilo(pos_h
, pos_l
);
927 ssize_t ret
= -EBADF
;
935 if (f
.file
->f_mode
& FMODE_PREAD
)
936 ret
= vfs_readv(f
.file
, vec
, vlen
, &pos
);
941 add_rchar(current
, ret
);
946 SYSCALL_DEFINE5(pwritev
, unsigned long, fd
, const struct iovec __user
*, vec
,
947 unsigned long, vlen
, unsigned long, pos_l
, unsigned long, pos_h
)
949 loff_t pos
= pos_from_hilo(pos_h
, pos_l
);
951 ssize_t ret
= -EBADF
;
959 if (f
.file
->f_mode
& FMODE_PWRITE
)
960 ret
= vfs_writev(f
.file
, vec
, vlen
, &pos
);
965 add_wchar(current
, ret
);
972 static ssize_t
compat_do_readv_writev(int type
, struct file
*file
,
973 const struct compat_iovec __user
*uvector
,
974 unsigned long nr_segs
, loff_t
*pos
)
976 compat_ssize_t tot_len
;
977 struct iovec iovstack
[UIO_FASTIOV
];
978 struct iovec
*iov
= iovstack
;
979 struct iov_iter iter
;
984 ret
= compat_import_iovec(type
, uvector
, nr_segs
,
985 UIO_FASTIOV
, &iov
, &iter
);
989 tot_len
= iov_iter_count(&iter
);
992 ret
= rw_verify_area(type
, file
, pos
, tot_len
);
997 fn
= file
->f_op
->read
;
998 iter_fn
= file
->f_op
->read_iter
;
1000 fn
= (io_fn_t
)file
->f_op
->write
;
1001 iter_fn
= file
->f_op
->write_iter
;
1002 file_start_write(file
);
1006 ret
= do_iter_readv_writev(file
, &iter
, pos
, iter_fn
);
1008 ret
= do_loop_readv_writev(file
, &iter
, pos
, fn
);
1011 file_end_write(file
);
1015 if ((ret
+ (type
== READ
)) > 0) {
1017 fsnotify_access(file
);
1019 fsnotify_modify(file
);
1024 static size_t compat_readv(struct file
*file
,
1025 const struct compat_iovec __user
*vec
,
1026 unsigned long vlen
, loff_t
*pos
)
1028 ssize_t ret
= -EBADF
;
1030 if (!(file
->f_mode
& FMODE_READ
))
1034 if (!(file
->f_mode
& FMODE_CAN_READ
))
1037 ret
= compat_do_readv_writev(READ
, file
, vec
, vlen
, pos
);
1041 add_rchar(current
, ret
);
1046 COMPAT_SYSCALL_DEFINE3(readv
, compat_ulong_t
, fd
,
1047 const struct compat_iovec __user
*,vec
,
1048 compat_ulong_t
, vlen
)
1050 struct fd f
= fdget_pos(fd
);
1056 pos
= f
.file
->f_pos
;
1057 ret
= compat_readv(f
.file
, vec
, vlen
, &pos
);
1059 f
.file
->f_pos
= pos
;
1064 static long __compat_sys_preadv64(unsigned long fd
,
1065 const struct compat_iovec __user
*vec
,
1066 unsigned long vlen
, loff_t pos
)
1077 if (f
.file
->f_mode
& FMODE_PREAD
)
1078 ret
= compat_readv(f
.file
, vec
, vlen
, &pos
);
1083 #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64
1084 COMPAT_SYSCALL_DEFINE4(preadv64
, unsigned long, fd
,
1085 const struct compat_iovec __user
*,vec
,
1086 unsigned long, vlen
, loff_t
, pos
)
1088 return __compat_sys_preadv64(fd
, vec
, vlen
, pos
);
1092 COMPAT_SYSCALL_DEFINE5(preadv
, compat_ulong_t
, fd
,
1093 const struct compat_iovec __user
*,vec
,
1094 compat_ulong_t
, vlen
, u32
, pos_low
, u32
, pos_high
)
1096 loff_t pos
= ((loff_t
)pos_high
<< 32) | pos_low
;
1098 return __compat_sys_preadv64(fd
, vec
, vlen
, pos
);
1101 static size_t compat_writev(struct file
*file
,
1102 const struct compat_iovec __user
*vec
,
1103 unsigned long vlen
, loff_t
*pos
)
1105 ssize_t ret
= -EBADF
;
1107 if (!(file
->f_mode
& FMODE_WRITE
))
1111 if (!(file
->f_mode
& FMODE_CAN_WRITE
))
1114 ret
= compat_do_readv_writev(WRITE
, file
, vec
, vlen
, pos
);
1118 add_wchar(current
, ret
);
1123 COMPAT_SYSCALL_DEFINE3(writev
, compat_ulong_t
, fd
,
1124 const struct compat_iovec __user
*, vec
,
1125 compat_ulong_t
, vlen
)
1127 struct fd f
= fdget_pos(fd
);
1133 pos
= f
.file
->f_pos
;
1134 ret
= compat_writev(f
.file
, vec
, vlen
, &pos
);
1136 f
.file
->f_pos
= pos
;
1141 static long __compat_sys_pwritev64(unsigned long fd
,
1142 const struct compat_iovec __user
*vec
,
1143 unsigned long vlen
, loff_t pos
)
1154 if (f
.file
->f_mode
& FMODE_PWRITE
)
1155 ret
= compat_writev(f
.file
, vec
, vlen
, &pos
);
1160 #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64
1161 COMPAT_SYSCALL_DEFINE4(pwritev64
, unsigned long, fd
,
1162 const struct compat_iovec __user
*,vec
,
1163 unsigned long, vlen
, loff_t
, pos
)
1165 return __compat_sys_pwritev64(fd
, vec
, vlen
, pos
);
1169 COMPAT_SYSCALL_DEFINE5(pwritev
, compat_ulong_t
, fd
,
1170 const struct compat_iovec __user
*,vec
,
1171 compat_ulong_t
, vlen
, u32
, pos_low
, u32
, pos_high
)
1173 loff_t pos
= ((loff_t
)pos_high
<< 32) | pos_low
;
1175 return __compat_sys_pwritev64(fd
, vec
, vlen
, pos
);
1179 static ssize_t
do_sendfile(int out_fd
, int in_fd
, loff_t
*ppos
,
1180 size_t count
, loff_t max
)
1183 struct inode
*in_inode
, *out_inode
;
1190 * Get input file, and verify that it is ok..
1196 if (!(in
.file
->f_mode
& FMODE_READ
))
1200 pos
= in
.file
->f_pos
;
1203 if (!(in
.file
->f_mode
& FMODE_PREAD
))
1206 retval
= rw_verify_area(READ
, in
.file
, &pos
, count
);
1212 * Get output file, and verify that it is ok..
1215 out
= fdget(out_fd
);
1218 if (!(out
.file
->f_mode
& FMODE_WRITE
))
1221 in_inode
= file_inode(in
.file
);
1222 out_inode
= file_inode(out
.file
);
1223 out_pos
= out
.file
->f_pos
;
1224 retval
= rw_verify_area(WRITE
, out
.file
, &out_pos
, count
);
1230 max
= min(in_inode
->i_sb
->s_maxbytes
, out_inode
->i_sb
->s_maxbytes
);
1232 if (unlikely(pos
+ count
> max
)) {
1233 retval
= -EOVERFLOW
;
1242 * We need to debate whether we can enable this or not. The
1243 * man page documents EAGAIN return for the output at least,
1244 * and the application is arguably buggy if it doesn't expect
1245 * EAGAIN on a non-blocking file descriptor.
1247 if (in
.file
->f_flags
& O_NONBLOCK
)
1248 fl
= SPLICE_F_NONBLOCK
;
1250 file_start_write(out
.file
);
1251 retval
= do_splice_direct(in
.file
, &pos
, out
.file
, &out_pos
, count
, fl
);
1252 file_end_write(out
.file
);
1255 add_rchar(current
, retval
);
1256 add_wchar(current
, retval
);
1257 fsnotify_access(in
.file
);
1258 fsnotify_modify(out
.file
);
1259 out
.file
->f_pos
= out_pos
;
1263 in
.file
->f_pos
= pos
;
1269 retval
= -EOVERFLOW
;
1279 SYSCALL_DEFINE4(sendfile
, int, out_fd
, int, in_fd
, off_t __user
*, offset
, size_t, count
)
1286 if (unlikely(get_user(off
, offset
)))
1289 ret
= do_sendfile(out_fd
, in_fd
, &pos
, count
, MAX_NON_LFS
);
1290 if (unlikely(put_user(pos
, offset
)))
1295 return do_sendfile(out_fd
, in_fd
, NULL
, count
, 0);
1298 SYSCALL_DEFINE4(sendfile64
, int, out_fd
, int, in_fd
, loff_t __user
*, offset
, size_t, count
)
1304 if (unlikely(copy_from_user(&pos
, offset
, sizeof(loff_t
))))
1306 ret
= do_sendfile(out_fd
, in_fd
, &pos
, count
, 0);
1307 if (unlikely(put_user(pos
, offset
)))
1312 return do_sendfile(out_fd
, in_fd
, NULL
, count
, 0);
1315 #ifdef CONFIG_COMPAT
1316 COMPAT_SYSCALL_DEFINE4(sendfile
, int, out_fd
, int, in_fd
,
1317 compat_off_t __user
*, offset
, compat_size_t
, count
)
1324 if (unlikely(get_user(off
, offset
)))
1327 ret
= do_sendfile(out_fd
, in_fd
, &pos
, count
, MAX_NON_LFS
);
1328 if (unlikely(put_user(pos
, offset
)))
1333 return do_sendfile(out_fd
, in_fd
, NULL
, count
, 0);
1336 COMPAT_SYSCALL_DEFINE4(sendfile64
, int, out_fd
, int, in_fd
,
1337 compat_loff_t __user
*, offset
, compat_size_t
, count
)
1343 if (unlikely(copy_from_user(&pos
, offset
, sizeof(loff_t
))))
1345 ret
= do_sendfile(out_fd
, in_fd
, &pos
, count
, 0);
1346 if (unlikely(put_user(pos
, offset
)))
1351 return do_sendfile(out_fd
, in_fd
, NULL
, count
, 0);