Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/read_write.c |
| 3 | * |
| 4 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 5 | */ |
| 6 | |
| 7 | #include <linux/slab.h> |
| 8 | #include <linux/stat.h> |
| 9 | #include <linux/fcntl.h> |
| 10 | #include <linux/file.h> |
| 11 | #include <linux/uio.h> |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 12 | #include <linux/fsnotify.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/security.h> |
Paul Gortmaker | 630d9c4 | 2011-11-16 23:57:37 -0500 | [diff] [blame] | 14 | #include <linux/export.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/syscalls.h> |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 16 | #include <linux/pagemap.h> |
Jens Axboe | d6b29d7 | 2007-06-04 09:59:47 +0200 | [diff] [blame] | 17 | #include <linux/splice.h> |
Al Viro | 561c673 | 2013-02-24 10:52:26 -0500 | [diff] [blame] | 18 | #include <linux/compat.h> |
Al Viro | 06ae43f | 2013-03-20 13:19:30 -0400 | [diff] [blame] | 19 | #include "internal.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | |
| 21 | #include <asm/uaccess.h> |
| 22 | #include <asm/unistd.h> |
| 23 | |
Al Viro | c0bd14af | 2013-05-04 15:00:54 -0400 | [diff] [blame] | 24 | typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *); |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 25 | typedef ssize_t (*iter_fn_t)(struct kiocb *, struct iov_iter *); |
Al Viro | c0bd14af | 2013-05-04 15:00:54 -0400 | [diff] [blame] | 26 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 27 | const struct file_operations generic_ro_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | .llseek = generic_file_llseek, |
Al Viro | aad4f8b | 2014-04-02 14:33:16 -0400 | [diff] [blame] | 29 | .read_iter = generic_file_read_iter, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | .mmap = generic_file_readonly_mmap, |
Jens Axboe | 534f2aa | 2007-06-01 14:52:37 +0200 | [diff] [blame] | 31 | .splice_read = generic_file_splice_read, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | }; |
| 33 | |
| 34 | EXPORT_SYMBOL(generic_ro_fops); |
| 35 | |
Al Viro | cccb5a1 | 2010-12-17 07:44:05 -0500 | [diff] [blame] | 36 | static inline int unsigned_offsets(struct file *file) |
KAMEZAWA Hiroyuki | 4a3956c | 2010-10-01 14:20:22 -0700 | [diff] [blame] | 37 | { |
Al Viro | cccb5a1 | 2010-12-17 07:44:05 -0500 | [diff] [blame] | 38 | return file->f_mode & FMODE_UNSIGNED_OFFSET; |
KAMEZAWA Hiroyuki | 4a3956c | 2010-10-01 14:20:22 -0700 | [diff] [blame] | 39 | } |
| 40 | |
Jie Liu | 46a1c2c | 2013-06-25 12:02:13 +0800 | [diff] [blame] | 41 | /** |
| 42 | * vfs_setpos - update the file offset for lseek |
| 43 | * @file: file structure in question |
| 44 | * @offset: file offset to seek to |
| 45 | * @maxsize: maximum file size |
| 46 | * |
| 47 | * This is a low-level filesystem helper for updating the file offset to |
| 48 | * the value specified by @offset if the given offset is valid and it is |
| 49 | * not equal to the current file offset. |
| 50 | * |
| 51 | * Return the specified offset on success and -EINVAL on invalid offset. |
| 52 | */ |
| 53 | loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize) |
Andi Kleen | ef3d0fd | 2011-09-15 16:06:48 -0700 | [diff] [blame] | 54 | { |
| 55 | if (offset < 0 && !unsigned_offsets(file)) |
| 56 | return -EINVAL; |
| 57 | if (offset > maxsize) |
| 58 | return -EINVAL; |
| 59 | |
| 60 | if (offset != file->f_pos) { |
| 61 | file->f_pos = offset; |
| 62 | file->f_version = 0; |
| 63 | } |
| 64 | return offset; |
| 65 | } |
Jie Liu | 46a1c2c | 2013-06-25 12:02:13 +0800 | [diff] [blame] | 66 | EXPORT_SYMBOL(vfs_setpos); |
Andi Kleen | ef3d0fd | 2011-09-15 16:06:48 -0700 | [diff] [blame] | 67 | |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 68 | /** |
Andi Kleen | 5760495 | 2011-09-15 16:06:50 -0700 | [diff] [blame] | 69 | * generic_file_llseek_size - generic llseek implementation for regular files |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 70 | * @file: file structure to seek on |
| 71 | * @offset: file offset to seek to |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 72 | * @whence: type of seek |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 73 | * @size: max size of this file in file system |
| 74 | * @eof: offset used for SEEK_END position |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 75 | * |
Andi Kleen | 5760495 | 2011-09-15 16:06:50 -0700 | [diff] [blame] | 76 | * This is a variant of generic_file_llseek that allows passing in a custom |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 77 | * maximum file size and a custom EOF position, for e.g. hashed directories |
Andi Kleen | ef3d0fd | 2011-09-15 16:06:48 -0700 | [diff] [blame] | 78 | * |
| 79 | * Synchronization: |
Andi Kleen | 5760495 | 2011-09-15 16:06:50 -0700 | [diff] [blame] | 80 | * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms) |
Andi Kleen | ef3d0fd | 2011-09-15 16:06:48 -0700 | [diff] [blame] | 81 | * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes. |
| 82 | * read/writes behave like SEEK_SET against seeks. |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 83 | */ |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 84 | loff_t |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 85 | generic_file_llseek_size(struct file *file, loff_t offset, int whence, |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 86 | loff_t maxsize, loff_t eof) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | { |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 88 | switch (whence) { |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 89 | case SEEK_END: |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 90 | offset += eof; |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 91 | break; |
| 92 | case SEEK_CUR: |
Alain Knaff | 5b6f1eb | 2008-11-10 17:08:08 -0800 | [diff] [blame] | 93 | /* |
| 94 | * Here we special-case the lseek(fd, 0, SEEK_CUR) |
| 95 | * position-querying operation. Avoid rewriting the "same" |
| 96 | * f_pos value back to the file because a concurrent read(), |
| 97 | * write() or lseek() might have altered it |
| 98 | */ |
| 99 | if (offset == 0) |
| 100 | return file->f_pos; |
Andi Kleen | ef3d0fd | 2011-09-15 16:06:48 -0700 | [diff] [blame] | 101 | /* |
| 102 | * f_lock protects against read/modify/write race with other |
| 103 | * SEEK_CURs. Note that parallel writes and reads behave |
| 104 | * like SEEK_SET. |
| 105 | */ |
| 106 | spin_lock(&file->f_lock); |
Jie Liu | 46a1c2c | 2013-06-25 12:02:13 +0800 | [diff] [blame] | 107 | offset = vfs_setpos(file, file->f_pos + offset, maxsize); |
Andi Kleen | ef3d0fd | 2011-09-15 16:06:48 -0700 | [diff] [blame] | 108 | spin_unlock(&file->f_lock); |
| 109 | return offset; |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 110 | case SEEK_DATA: |
| 111 | /* |
| 112 | * In the generic case the entire file is data, so as long as |
| 113 | * offset isn't at the end of the file then the offset is data. |
| 114 | */ |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 115 | if (offset >= eof) |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 116 | return -ENXIO; |
| 117 | break; |
| 118 | case SEEK_HOLE: |
| 119 | /* |
| 120 | * There is a virtual hole at the end of the file, so as long as |
| 121 | * offset isn't i_size or larger, return i_size. |
| 122 | */ |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 123 | if (offset >= eof) |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 124 | return -ENXIO; |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 125 | offset = eof; |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 126 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | } |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 128 | |
Jie Liu | 46a1c2c | 2013-06-25 12:02:13 +0800 | [diff] [blame] | 129 | return vfs_setpos(file, offset, maxsize); |
Andi Kleen | 5760495 | 2011-09-15 16:06:50 -0700 | [diff] [blame] | 130 | } |
| 131 | EXPORT_SYMBOL(generic_file_llseek_size); |
| 132 | |
| 133 | /** |
| 134 | * generic_file_llseek - generic llseek implementation for regular files |
| 135 | * @file: file structure to seek on |
| 136 | * @offset: file offset to seek to |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 137 | * @whence: type of seek |
Andi Kleen | 5760495 | 2011-09-15 16:06:50 -0700 | [diff] [blame] | 138 | * |
| 139 | * This is a generic implemenation of ->llseek useable for all normal local |
| 140 | * filesystems. It just updates the file offset to the value specified by |
Ming Lei | 546ae2d | 2013-04-29 15:06:07 -0700 | [diff] [blame] | 141 | * @offset and @whence. |
Andi Kleen | 5760495 | 2011-09-15 16:06:50 -0700 | [diff] [blame] | 142 | */ |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 143 | loff_t generic_file_llseek(struct file *file, loff_t offset, int whence) |
Andi Kleen | 5760495 | 2011-09-15 16:06:50 -0700 | [diff] [blame] | 144 | { |
| 145 | struct inode *inode = file->f_mapping->host; |
| 146 | |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 147 | return generic_file_llseek_size(file, offset, whence, |
Eric Sandeen | e8b96eb | 2012-04-30 13:11:29 -0500 | [diff] [blame] | 148 | inode->i_sb->s_maxbytes, |
| 149 | i_size_read(inode)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | } |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 151 | EXPORT_SYMBOL(generic_file_llseek); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | |
jan Blunck | ae6afc3 | 2010-05-26 14:44:48 -0700 | [diff] [blame] | 153 | /** |
Al Viro | 1bf9d14 | 2013-06-16 20:27:42 +0400 | [diff] [blame] | 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 |
| 159 | * |
| 160 | */ |
| 161 | loff_t fixed_size_llseek(struct file *file, loff_t offset, int whence, loff_t size) |
| 162 | { |
| 163 | switch (whence) { |
| 164 | case SEEK_SET: case SEEK_CUR: case SEEK_END: |
| 165 | return generic_file_llseek_size(file, offset, whence, |
| 166 | size, size); |
| 167 | default: |
| 168 | return -EINVAL; |
| 169 | } |
| 170 | } |
| 171 | EXPORT_SYMBOL(fixed_size_llseek); |
| 172 | |
| 173 | /** |
Al Viro | b25472f | 2015-12-05 22:04:48 -0500 | [diff] [blame^] | 174 | * no_seek_end_llseek - llseek implementation for fixed-sized devices |
| 175 | * @file: file structure to seek on |
| 176 | * @offset: file offset to seek to |
| 177 | * @whence: type of seek |
| 178 | * |
| 179 | */ |
| 180 | loff_t no_seek_end_llseek(struct file *file, loff_t offset, int whence) |
| 181 | { |
| 182 | switch (whence) { |
| 183 | case SEEK_SET: case SEEK_CUR: |
| 184 | return generic_file_llseek_size(file, offset, whence, |
| 185 | ~0ULL, 0); |
| 186 | default: |
| 187 | return -EINVAL; |
| 188 | } |
| 189 | } |
| 190 | EXPORT_SYMBOL(no_seek_end_llseek); |
| 191 | |
| 192 | /** |
| 193 | * no_seek_end_llseek_size - llseek implementation for fixed-sized devices |
| 194 | * @file: file structure to seek on |
| 195 | * @offset: file offset to seek to |
| 196 | * @whence: type of seek |
| 197 | * @size: maximal offset allowed |
| 198 | * |
| 199 | */ |
| 200 | loff_t no_seek_end_llseek_size(struct file *file, loff_t offset, int whence, loff_t size) |
| 201 | { |
| 202 | switch (whence) { |
| 203 | case SEEK_SET: case SEEK_CUR: |
| 204 | return generic_file_llseek_size(file, offset, whence, |
| 205 | size, 0); |
| 206 | default: |
| 207 | return -EINVAL; |
| 208 | } |
| 209 | } |
| 210 | EXPORT_SYMBOL(no_seek_end_llseek_size); |
| 211 | |
| 212 | /** |
jan Blunck | ae6afc3 | 2010-05-26 14:44:48 -0700 | [diff] [blame] | 213 | * noop_llseek - No Operation Performed llseek implementation |
| 214 | * @file: file structure to seek on |
| 215 | * @offset: file offset to seek to |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 216 | * @whence: type of seek |
jan Blunck | ae6afc3 | 2010-05-26 14:44:48 -0700 | [diff] [blame] | 217 | * |
| 218 | * This is an implementation of ->llseek useable for the rare special case when |
| 219 | * userspace expects the seek to succeed but the (device) file is actually not |
| 220 | * able to perform the seek. In this case you use noop_llseek() instead of |
| 221 | * falling back to the default implementation of ->llseek. |
| 222 | */ |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 223 | loff_t noop_llseek(struct file *file, loff_t offset, int whence) |
jan Blunck | ae6afc3 | 2010-05-26 14:44:48 -0700 | [diff] [blame] | 224 | { |
| 225 | return file->f_pos; |
| 226 | } |
| 227 | EXPORT_SYMBOL(noop_llseek); |
| 228 | |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 229 | loff_t no_llseek(struct file *file, loff_t offset, int whence) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | { |
| 231 | return -ESPIPE; |
| 232 | } |
| 233 | EXPORT_SYMBOL(no_llseek); |
| 234 | |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 235 | loff_t default_llseek(struct file *file, loff_t offset, int whence) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | { |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 237 | struct inode *inode = file_inode(file); |
David Sterba | 16abef0 | 2008-04-22 15:09:22 +0200 | [diff] [blame] | 238 | loff_t retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 240 | mutex_lock(&inode->i_mutex); |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 241 | switch (whence) { |
Chris Snook | 7b8e892 | 2007-05-08 00:24:13 -0700 | [diff] [blame] | 242 | case SEEK_END: |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 243 | offset += i_size_read(inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | break; |
Chris Snook | 7b8e892 | 2007-05-08 00:24:13 -0700 | [diff] [blame] | 245 | case SEEK_CUR: |
Alain Knaff | 5b6f1eb | 2008-11-10 17:08:08 -0800 | [diff] [blame] | 246 | if (offset == 0) { |
| 247 | retval = file->f_pos; |
| 248 | goto out; |
| 249 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | offset += file->f_pos; |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 251 | break; |
| 252 | case SEEK_DATA: |
| 253 | /* |
| 254 | * In the generic case the entire file is data, so as |
| 255 | * long as offset isn't at the end of the file then the |
| 256 | * offset is data. |
| 257 | */ |
Dan Carpenter | bacb2d8 | 2011-07-26 17:25:20 +0300 | [diff] [blame] | 258 | if (offset >= inode->i_size) { |
| 259 | retval = -ENXIO; |
| 260 | goto out; |
| 261 | } |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 262 | break; |
| 263 | case SEEK_HOLE: |
| 264 | /* |
| 265 | * There is a virtual hole at the end of the file, so |
| 266 | * as long as offset isn't i_size or larger, return |
| 267 | * i_size. |
| 268 | */ |
Dan Carpenter | bacb2d8 | 2011-07-26 17:25:20 +0300 | [diff] [blame] | 269 | if (offset >= inode->i_size) { |
| 270 | retval = -ENXIO; |
| 271 | goto out; |
| 272 | } |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 273 | offset = inode->i_size; |
| 274 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | } |
| 276 | retval = -EINVAL; |
Al Viro | cccb5a1 | 2010-12-17 07:44:05 -0500 | [diff] [blame] | 277 | if (offset >= 0 || unsigned_offsets(file)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | if (offset != file->f_pos) { |
| 279 | file->f_pos = offset; |
| 280 | file->f_version = 0; |
| 281 | } |
| 282 | retval = offset; |
| 283 | } |
Alain Knaff | 5b6f1eb | 2008-11-10 17:08:08 -0800 | [diff] [blame] | 284 | out: |
Josef Bacik | 982d816 | 2011-07-18 13:21:35 -0400 | [diff] [blame] | 285 | mutex_unlock(&inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | return retval; |
| 287 | } |
| 288 | EXPORT_SYMBOL(default_llseek); |
| 289 | |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 290 | loff_t vfs_llseek(struct file *file, loff_t offset, int whence) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | { |
| 292 | loff_t (*fn)(struct file *, loff_t, int); |
| 293 | |
| 294 | fn = no_llseek; |
| 295 | if (file->f_mode & FMODE_LSEEK) { |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 296 | if (file->f_op->llseek) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | fn = file->f_op->llseek; |
| 298 | } |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 299 | return fn(file, offset, whence); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | } |
| 301 | EXPORT_SYMBOL(vfs_llseek); |
| 302 | |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 303 | static inline struct fd fdget_pos(int fd) |
| 304 | { |
Al Viro | bd2a31d | 2014-03-04 14:54:22 -0500 | [diff] [blame] | 305 | return __to_fd(__fdget_pos(fd)); |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 306 | } |
| 307 | |
| 308 | static inline void fdput_pos(struct fd f) |
| 309 | { |
| 310 | if (f.flags & FDPUT_POS_UNLOCK) |
| 311 | mutex_unlock(&f.file->f_pos_lock); |
| 312 | fdput(f); |
| 313 | } |
| 314 | |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 315 | SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | { |
| 317 | off_t retval; |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 318 | struct fd f = fdget_pos(fd); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 319 | if (!f.file) |
| 320 | return -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | |
| 322 | retval = -EINVAL; |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 323 | if (whence <= SEEK_MAX) { |
| 324 | loff_t res = vfs_llseek(f.file, offset, whence); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | retval = res; |
| 326 | if (res != (loff_t)retval) |
| 327 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ |
| 328 | } |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 329 | fdput_pos(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 330 | return retval; |
| 331 | } |
| 332 | |
Al Viro | 561c673 | 2013-02-24 10:52:26 -0500 | [diff] [blame] | 333 | #ifdef CONFIG_COMPAT |
| 334 | COMPAT_SYSCALL_DEFINE3(lseek, unsigned int, fd, compat_off_t, offset, unsigned int, whence) |
| 335 | { |
| 336 | return sys_lseek(fd, offset, whence); |
| 337 | } |
| 338 | #endif |
| 339 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | #ifdef __ARCH_WANT_SYS_LLSEEK |
Heiko Carstens | 003d7ab | 2009-01-14 14:14:21 +0100 | [diff] [blame] | 341 | SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, |
| 342 | unsigned long, offset_low, loff_t __user *, result, |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 343 | unsigned int, whence) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | { |
| 345 | int retval; |
Eric Biggers | d7a15f8 | 2014-03-16 14:24:08 -0500 | [diff] [blame] | 346 | struct fd f = fdget_pos(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | loff_t offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 349 | if (!f.file) |
| 350 | return -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | |
| 352 | retval = -EINVAL; |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 353 | if (whence > SEEK_MAX) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | goto out_putf; |
| 355 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 356 | offset = vfs_llseek(f.file, ((loff_t) offset_high << 32) | offset_low, |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 357 | whence); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | |
| 359 | retval = (int)offset; |
| 360 | if (offset >= 0) { |
| 361 | retval = -EFAULT; |
| 362 | if (!copy_to_user(result, &offset, sizeof(offset))) |
| 363 | retval = 0; |
| 364 | } |
| 365 | out_putf: |
Eric Biggers | d7a15f8 | 2014-03-16 14:24:08 -0500 | [diff] [blame] | 366 | fdput_pos(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | return retval; |
| 368 | } |
| 369 | #endif |
| 370 | |
Christoph Hellwig | dbe4e19 | 2015-01-25 21:11:59 +0100 | [diff] [blame] | 371 | ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos) |
| 372 | { |
| 373 | struct kiocb kiocb; |
| 374 | ssize_t ret; |
| 375 | |
| 376 | if (!file->f_op->read_iter) |
| 377 | return -EINVAL; |
| 378 | |
| 379 | init_sync_kiocb(&kiocb, file); |
| 380 | kiocb.ki_pos = *ppos; |
Christoph Hellwig | dbe4e19 | 2015-01-25 21:11:59 +0100 | [diff] [blame] | 381 | |
| 382 | iter->type |= READ; |
| 383 | ret = file->f_op->read_iter(&kiocb, iter); |
Christoph Hellwig | 599bd19 | 2015-02-11 19:59:44 +0100 | [diff] [blame] | 384 | BUG_ON(ret == -EIOCBQUEUED); |
Christoph Hellwig | dbe4e19 | 2015-01-25 21:11:59 +0100 | [diff] [blame] | 385 | if (ret > 0) |
| 386 | *ppos = kiocb.ki_pos; |
| 387 | return ret; |
| 388 | } |
| 389 | EXPORT_SYMBOL(vfs_iter_read); |
| 390 | |
| 391 | ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos) |
| 392 | { |
| 393 | struct kiocb kiocb; |
| 394 | ssize_t ret; |
| 395 | |
| 396 | if (!file->f_op->write_iter) |
| 397 | return -EINVAL; |
| 398 | |
| 399 | init_sync_kiocb(&kiocb, file); |
| 400 | kiocb.ki_pos = *ppos; |
Christoph Hellwig | dbe4e19 | 2015-01-25 21:11:59 +0100 | [diff] [blame] | 401 | |
| 402 | iter->type |= WRITE; |
| 403 | ret = file->f_op->write_iter(&kiocb, iter); |
Christoph Hellwig | 599bd19 | 2015-02-11 19:59:44 +0100 | [diff] [blame] | 404 | BUG_ON(ret == -EIOCBQUEUED); |
Christoph Hellwig | dbe4e19 | 2015-01-25 21:11:59 +0100 | [diff] [blame] | 405 | if (ret > 0) |
| 406 | *ppos = kiocb.ki_pos; |
| 407 | return ret; |
| 408 | } |
| 409 | EXPORT_SYMBOL(vfs_iter_write); |
| 410 | |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 411 | /* |
| 412 | * rw_verify_area doesn't like huge counts. We limit |
| 413 | * them to something that fits in "int" so that others |
| 414 | * won't have to do range checks all the time. |
| 415 | */ |
Al Viro | 68d70d0 | 2013-06-19 15:26:04 +0400 | [diff] [blame] | 416 | int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | { |
| 418 | struct inode *inode; |
| 419 | loff_t pos; |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 420 | int retval = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 422 | inode = file_inode(file); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 423 | if (unlikely((ssize_t) count < 0)) |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 424 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | pos = *ppos; |
Al Viro | cccb5a1 | 2010-12-17 07:44:05 -0500 | [diff] [blame] | 426 | if (unlikely(pos < 0)) { |
| 427 | if (!unsigned_offsets(file)) |
| 428 | return retval; |
| 429 | if (count >= -pos) /* both values are in 0..LLONG_MAX */ |
| 430 | return -EOVERFLOW; |
| 431 | } else if (unlikely((loff_t) (pos + count) < 0)) { |
| 432 | if (!unsigned_offsets(file)) |
KAMEZAWA Hiroyuki | 4a3956c | 2010-10-01 14:20:22 -0700 | [diff] [blame] | 433 | return retval; |
| 434 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 435 | |
Jeff Layton | bd61e0a | 2015-01-16 15:05:55 -0500 | [diff] [blame] | 436 | if (unlikely(inode->i_flctx && mandatory_lock(inode))) { |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 437 | retval = locks_mandatory_area( |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 438 | read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, |
| 439 | inode, file, pos, count); |
| 440 | if (retval < 0) |
| 441 | return retval; |
| 442 | } |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 443 | retval = security_file_permission(file, |
| 444 | read_write == READ ? MAY_READ : MAY_WRITE); |
| 445 | if (retval) |
| 446 | return retval; |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 447 | return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | } |
| 449 | |
Al Viro | 5d5d568 | 2015-04-03 15:41:18 -0400 | [diff] [blame] | 450 | static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 451 | { |
| 452 | struct iovec iov = { .iov_base = buf, .iov_len = len }; |
| 453 | struct kiocb kiocb; |
| 454 | struct iov_iter iter; |
| 455 | ssize_t ret; |
| 456 | |
| 457 | init_sync_kiocb(&kiocb, filp); |
| 458 | kiocb.ki_pos = *ppos; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 459 | iov_iter_init(&iter, READ, &iov, 1, len); |
| 460 | |
| 461 | ret = filp->f_op->read_iter(&kiocb, &iter); |
Christoph Hellwig | 599bd19 | 2015-02-11 19:59:44 +0100 | [diff] [blame] | 462 | BUG_ON(ret == -EIOCBQUEUED); |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 463 | *ppos = kiocb.ki_pos; |
| 464 | return ret; |
| 465 | } |
| 466 | |
Dmitry Kasatkin | 6fb5032 | 2014-11-05 17:01:17 +0200 | [diff] [blame] | 467 | ssize_t __vfs_read(struct file *file, char __user *buf, size_t count, |
| 468 | loff_t *pos) |
| 469 | { |
Dmitry Kasatkin | 6fb5032 | 2014-11-05 17:01:17 +0200 | [diff] [blame] | 470 | if (file->f_op->read) |
Al Viro | 3d04c8a | 2015-04-03 15:09:18 -0400 | [diff] [blame] | 471 | return file->f_op->read(file, buf, count, pos); |
Dmitry Kasatkin | 6fb5032 | 2014-11-05 17:01:17 +0200 | [diff] [blame] | 472 | else if (file->f_op->read_iter) |
Al Viro | 3d04c8a | 2015-04-03 15:09:18 -0400 | [diff] [blame] | 473 | return new_sync_read(file, buf, count, pos); |
Dmitry Kasatkin | 6fb5032 | 2014-11-05 17:01:17 +0200 | [diff] [blame] | 474 | else |
Al Viro | 3d04c8a | 2015-04-03 15:09:18 -0400 | [diff] [blame] | 475 | return -EINVAL; |
Dmitry Kasatkin | 6fb5032 | 2014-11-05 17:01:17 +0200 | [diff] [blame] | 476 | } |
Al Viro | 3d04c8a | 2015-04-03 15:09:18 -0400 | [diff] [blame] | 477 | EXPORT_SYMBOL(__vfs_read); |
Dmitry Kasatkin | 6fb5032 | 2014-11-05 17:01:17 +0200 | [diff] [blame] | 478 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) |
| 480 | { |
| 481 | ssize_t ret; |
| 482 | |
| 483 | if (!(file->f_mode & FMODE_READ)) |
| 484 | return -EBADF; |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 485 | if (!(file->f_mode & FMODE_CAN_READ)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | return -EINVAL; |
| 487 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) |
| 488 | return -EFAULT; |
| 489 | |
| 490 | ret = rw_verify_area(READ, file, pos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 491 | if (ret >= 0) { |
| 492 | count = ret; |
Dmitry Kasatkin | 6fb5032 | 2014-11-05 17:01:17 +0200 | [diff] [blame] | 493 | ret = __vfs_read(file, buf, count, pos); |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 494 | if (ret > 0) { |
Eric Paris | 2a12a9d | 2009-12-17 21:24:21 -0500 | [diff] [blame] | 495 | fsnotify_access(file); |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 496 | add_rchar(current, ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | } |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 498 | inc_syscr(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | } |
| 500 | |
| 501 | return ret; |
| 502 | } |
| 503 | |
| 504 | EXPORT_SYMBOL(vfs_read); |
| 505 | |
Al Viro | 5d5d568 | 2015-04-03 15:41:18 -0400 | [diff] [blame] | 506 | static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 507 | { |
| 508 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; |
| 509 | struct kiocb kiocb; |
| 510 | struct iov_iter iter; |
| 511 | ssize_t ret; |
| 512 | |
| 513 | init_sync_kiocb(&kiocb, filp); |
| 514 | kiocb.ki_pos = *ppos; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 515 | iov_iter_init(&iter, WRITE, &iov, 1, len); |
| 516 | |
| 517 | ret = filp->f_op->write_iter(&kiocb, &iter); |
Christoph Hellwig | 599bd19 | 2015-02-11 19:59:44 +0100 | [diff] [blame] | 518 | BUG_ON(ret == -EIOCBQUEUED); |
Al Viro | f765b13 | 2015-04-06 20:50:38 -0400 | [diff] [blame] | 519 | if (ret > 0) |
| 520 | *ppos = kiocb.ki_pos; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 521 | return ret; |
| 522 | } |
| 523 | |
Al Viro | 493c84c | 2015-04-03 15:06:43 -0400 | [diff] [blame] | 524 | ssize_t __vfs_write(struct file *file, const char __user *p, size_t count, |
| 525 | loff_t *pos) |
| 526 | { |
| 527 | if (file->f_op->write) |
| 528 | return file->f_op->write(file, p, count, pos); |
Al Viro | 493c84c | 2015-04-03 15:06:43 -0400 | [diff] [blame] | 529 | else if (file->f_op->write_iter) |
| 530 | return new_sync_write(file, p, count, pos); |
| 531 | else |
| 532 | return -EINVAL; |
| 533 | } |
| 534 | EXPORT_SYMBOL(__vfs_write); |
| 535 | |
Al Viro | 06ae43f | 2013-03-20 13:19:30 -0400 | [diff] [blame] | 536 | ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos) |
| 537 | { |
| 538 | mm_segment_t old_fs; |
| 539 | const char __user *p; |
| 540 | ssize_t ret; |
| 541 | |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 542 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
Al Viro | 3e84f48 | 2013-03-27 15:20:30 +0000 | [diff] [blame] | 543 | return -EINVAL; |
| 544 | |
Al Viro | 06ae43f | 2013-03-20 13:19:30 -0400 | [diff] [blame] | 545 | old_fs = get_fs(); |
| 546 | set_fs(get_ds()); |
| 547 | p = (__force const char __user *)buf; |
| 548 | if (count > MAX_RW_COUNT) |
| 549 | count = MAX_RW_COUNT; |
Al Viro | 493c84c | 2015-04-03 15:06:43 -0400 | [diff] [blame] | 550 | ret = __vfs_write(file, p, count, pos); |
Al Viro | 06ae43f | 2013-03-20 13:19:30 -0400 | [diff] [blame] | 551 | set_fs(old_fs); |
| 552 | if (ret > 0) { |
| 553 | fsnotify_modify(file); |
| 554 | add_wchar(current, ret); |
| 555 | } |
| 556 | inc_syscw(current); |
| 557 | return ret; |
| 558 | } |
| 559 | |
Al Viro | 2ec3a12 | 2014-08-19 11:48:09 -0400 | [diff] [blame] | 560 | EXPORT_SYMBOL(__kernel_write); |
| 561 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
| 563 | { |
| 564 | ssize_t ret; |
| 565 | |
| 566 | if (!(file->f_mode & FMODE_WRITE)) |
| 567 | return -EBADF; |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 568 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 569 | return -EINVAL; |
| 570 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) |
| 571 | return -EFAULT; |
| 572 | |
| 573 | ret = rw_verify_area(WRITE, file, pos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 574 | if (ret >= 0) { |
| 575 | count = ret; |
Al Viro | 03d95eb | 2013-03-20 13:04:20 -0400 | [diff] [blame] | 576 | file_start_write(file); |
Al Viro | 493c84c | 2015-04-03 15:06:43 -0400 | [diff] [blame] | 577 | ret = __vfs_write(file, buf, count, pos); |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 578 | if (ret > 0) { |
Eric Paris | 2a12a9d | 2009-12-17 21:24:21 -0500 | [diff] [blame] | 579 | fsnotify_modify(file); |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 580 | add_wchar(current, ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | } |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 582 | inc_syscw(current); |
Al Viro | 03d95eb | 2013-03-20 13:04:20 -0400 | [diff] [blame] | 583 | file_end_write(file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | } |
| 585 | |
| 586 | return ret; |
| 587 | } |
| 588 | |
| 589 | EXPORT_SYMBOL(vfs_write); |
| 590 | |
| 591 | static inline loff_t file_pos_read(struct file *file) |
| 592 | { |
| 593 | return file->f_pos; |
| 594 | } |
| 595 | |
| 596 | static inline void file_pos_write(struct file *file, loff_t pos) |
| 597 | { |
| 598 | file->f_pos = pos; |
| 599 | } |
| 600 | |
Heiko Carstens | 3cdad42 | 2009-01-14 14:14:22 +0100 | [diff] [blame] | 601 | SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | { |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 603 | struct fd f = fdget_pos(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 604 | ssize_t ret = -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 606 | if (f.file) { |
| 607 | loff_t pos = file_pos_read(f.file); |
| 608 | ret = vfs_read(f.file, buf, count, &pos); |
Al Viro | 5faf153 | 2013-06-15 05:49:36 +0400 | [diff] [blame] | 609 | if (ret >= 0) |
| 610 | file_pos_write(f.file, pos); |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 611 | fdput_pos(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 613 | return ret; |
| 614 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | |
Heiko Carstens | 3cdad42 | 2009-01-14 14:14:22 +0100 | [diff] [blame] | 616 | SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, |
| 617 | size_t, count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 618 | { |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 619 | struct fd f = fdget_pos(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | ssize_t ret = -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 622 | if (f.file) { |
| 623 | loff_t pos = file_pos_read(f.file); |
| 624 | ret = vfs_write(f.file, buf, count, &pos); |
Al Viro | 5faf153 | 2013-06-15 05:49:36 +0400 | [diff] [blame] | 625 | if (ret >= 0) |
| 626 | file_pos_write(f.file, pos); |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 627 | fdput_pos(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 628 | } |
| 629 | |
| 630 | return ret; |
| 631 | } |
| 632 | |
Al Viro | 4a0fd5b | 2013-01-21 15:16:58 -0500 | [diff] [blame] | 633 | SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, |
| 634 | size_t, count, loff_t, pos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 636 | struct fd f; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 637 | ssize_t ret = -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | |
| 639 | if (pos < 0) |
| 640 | return -EINVAL; |
| 641 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 642 | f = fdget(fd); |
| 643 | if (f.file) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | ret = -ESPIPE; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 645 | if (f.file->f_mode & FMODE_PREAD) |
| 646 | ret = vfs_read(f.file, buf, count, &pos); |
| 647 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 648 | } |
| 649 | |
| 650 | return ret; |
| 651 | } |
| 652 | |
Al Viro | 4a0fd5b | 2013-01-21 15:16:58 -0500 | [diff] [blame] | 653 | SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, |
| 654 | size_t, count, loff_t, pos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 656 | struct fd f; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | ssize_t ret = -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 658 | |
| 659 | if (pos < 0) |
| 660 | return -EINVAL; |
| 661 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 662 | f = fdget(fd); |
| 663 | if (f.file) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | ret = -ESPIPE; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 665 | if (f.file->f_mode & FMODE_PWRITE) |
| 666 | ret = vfs_write(f.file, buf, count, &pos); |
| 667 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | } |
| 669 | |
| 670 | return ret; |
| 671 | } |
| 672 | |
| 673 | /* |
| 674 | * Reduce an iovec's length in-place. Return the resulting number of segments |
| 675 | */ |
| 676 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) |
| 677 | { |
| 678 | unsigned long seg = 0; |
| 679 | size_t len = 0; |
| 680 | |
| 681 | while (seg < nr_segs) { |
| 682 | seg++; |
| 683 | if (len + iov->iov_len >= to) { |
| 684 | iov->iov_len = to - len; |
| 685 | break; |
| 686 | } |
| 687 | len += iov->iov_len; |
| 688 | iov++; |
| 689 | } |
| 690 | return seg; |
| 691 | } |
Eric Sandeen | 1929552 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 692 | EXPORT_SYMBOL(iov_shorten); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 693 | |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 694 | static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, |
| 695 | loff_t *ppos, iter_fn_t fn) |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 696 | { |
| 697 | struct kiocb kiocb; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 698 | ssize_t ret; |
| 699 | |
| 700 | init_sync_kiocb(&kiocb, filp); |
| 701 | kiocb.ki_pos = *ppos; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 702 | |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 703 | ret = fn(&kiocb, iter); |
Christoph Hellwig | 599bd19 | 2015-02-11 19:59:44 +0100 | [diff] [blame] | 704 | BUG_ON(ret == -EIOCBQUEUED); |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 705 | *ppos = kiocb.ki_pos; |
| 706 | return ret; |
| 707 | } |
| 708 | |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 709 | /* Do it by hand, with file-ops */ |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 710 | static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, |
| 711 | loff_t *ppos, io_fn_t fn) |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 712 | { |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 713 | ssize_t ret = 0; |
| 714 | |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 715 | while (iov_iter_count(iter)) { |
| 716 | struct iovec iovec = iov_iter_iovec(iter); |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 717 | ssize_t nr; |
| 718 | |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 719 | nr = fn(filp, iovec.iov_base, iovec.iov_len, ppos); |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 720 | |
| 721 | if (nr < 0) { |
| 722 | if (!ret) |
| 723 | ret = nr; |
| 724 | break; |
| 725 | } |
| 726 | ret += nr; |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 727 | if (nr != iovec.iov_len) |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 728 | break; |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 729 | iov_iter_advance(iter, nr); |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 730 | } |
| 731 | |
| 732 | return ret; |
| 733 | } |
| 734 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | /* A write operation does a read from user space and vice versa */ |
| 736 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) |
| 737 | |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 738 | ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, |
| 739 | unsigned long nr_segs, unsigned long fast_segs, |
| 740 | struct iovec *fast_pointer, |
Christopher Yeoh | ac34ebb | 2012-05-31 16:26:42 -0700 | [diff] [blame] | 741 | struct iovec **ret_pointer) |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 742 | { |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 743 | unsigned long seg; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 744 | ssize_t ret; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 745 | struct iovec *iov = fast_pointer; |
| 746 | |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 747 | /* |
| 748 | * SuS says "The readv() function *may* fail if the iovcnt argument |
| 749 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has |
| 750 | * traditionally returned zero for zero segments, so... |
| 751 | */ |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 752 | if (nr_segs == 0) { |
| 753 | ret = 0; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 754 | goto out; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 755 | } |
| 756 | |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 757 | /* |
| 758 | * First get the "struct iovec" from user memory and |
| 759 | * verify all the pointers |
| 760 | */ |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 761 | if (nr_segs > UIO_MAXIOV) { |
| 762 | ret = -EINVAL; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 763 | goto out; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 764 | } |
| 765 | if (nr_segs > fast_segs) { |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 766 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 767 | if (iov == NULL) { |
| 768 | ret = -ENOMEM; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 769 | goto out; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 770 | } |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 771 | } |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 772 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { |
| 773 | ret = -EFAULT; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 774 | goto out; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 775 | } |
| 776 | |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 777 | /* |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 778 | * According to the Single Unix Specification we should return EINVAL |
| 779 | * if an element length is < 0 when cast to ssize_t or if the |
| 780 | * total length would overflow the ssize_t return value of the |
| 781 | * system call. |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 782 | * |
| 783 | * Linux caps all read/write calls to MAX_RW_COUNT, and avoids the |
| 784 | * overflow case. |
| 785 | */ |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 786 | ret = 0; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 787 | for (seg = 0; seg < nr_segs; seg++) { |
| 788 | void __user *buf = iov[seg].iov_base; |
| 789 | ssize_t len = (ssize_t)iov[seg].iov_len; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 790 | |
| 791 | /* see if we we're about to use an invalid len or if |
| 792 | * it's about to overflow ssize_t */ |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 793 | if (len < 0) { |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 794 | ret = -EINVAL; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 795 | goto out; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 796 | } |
Christopher Yeoh | ac34ebb | 2012-05-31 16:26:42 -0700 | [diff] [blame] | 797 | if (type >= 0 |
Christopher Yeoh | fcf6340 | 2011-10-31 17:06:39 -0700 | [diff] [blame] | 798 | && unlikely(!access_ok(vrfy_dir(type), buf, len))) { |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 799 | ret = -EFAULT; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 800 | goto out; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 801 | } |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 802 | if (len > MAX_RW_COUNT - ret) { |
| 803 | len = MAX_RW_COUNT - ret; |
| 804 | iov[seg].iov_len = len; |
| 805 | } |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 806 | ret += len; |
Linus Torvalds | 435f49a | 2010-10-29 10:36:49 -0700 | [diff] [blame] | 807 | } |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 808 | out: |
| 809 | *ret_pointer = iov; |
| 810 | return ret; |
| 811 | } |
| 812 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 813 | static ssize_t do_readv_writev(int type, struct file *file, |
| 814 | const struct iovec __user * uvector, |
| 815 | unsigned long nr_segs, loff_t *pos) |
| 816 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | size_t tot_len; |
| 818 | struct iovec iovstack[UIO_FASTIOV]; |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 819 | struct iovec *iov = iovstack; |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 820 | struct iov_iter iter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 821 | ssize_t ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | io_fn_t fn; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 823 | iter_fn_t iter_fn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 824 | |
Al Viro | 0504c07 | 2015-03-21 19:40:11 -0400 | [diff] [blame] | 825 | ret = import_iovec(type, uvector, nr_segs, |
| 826 | ARRAY_SIZE(iovstack), &iov, &iter); |
| 827 | if (ret < 0) |
| 828 | return ret; |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 829 | |
Al Viro | 0504c07 | 2015-03-21 19:40:11 -0400 | [diff] [blame] | 830 | tot_len = iov_iter_count(&iter); |
| 831 | if (!tot_len) |
| 832 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | ret = rw_verify_area(type, file, pos, tot_len); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 834 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 835 | goto out; |
| 836 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | if (type == READ) { |
| 838 | fn = file->f_op->read; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 839 | iter_fn = file->f_op->read_iter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 840 | } else { |
| 841 | fn = (io_fn_t)file->f_op->write; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 842 | iter_fn = file->f_op->write_iter; |
Al Viro | 03d95eb | 2013-03-20 13:04:20 -0400 | [diff] [blame] | 843 | file_start_write(file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 844 | } |
| 845 | |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 846 | if (iter_fn) |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 847 | ret = do_iter_readv_writev(file, &iter, pos, iter_fn); |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 848 | else |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 849 | ret = do_loop_readv_writev(file, &iter, pos, fn); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 850 | |
Al Viro | 03d95eb | 2013-03-20 13:04:20 -0400 | [diff] [blame] | 851 | if (type != READ) |
| 852 | file_end_write(file); |
| 853 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 854 | out: |
Al Viro | 0504c07 | 2015-03-21 19:40:11 -0400 | [diff] [blame] | 855 | kfree(iov); |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 856 | if ((ret + (type == READ)) > 0) { |
| 857 | if (type == READ) |
Eric Paris | 2a12a9d | 2009-12-17 21:24:21 -0500 | [diff] [blame] | 858 | fsnotify_access(file); |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 859 | else |
Eric Paris | 2a12a9d | 2009-12-17 21:24:21 -0500 | [diff] [blame] | 860 | fsnotify_modify(file); |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 861 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 862 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 863 | } |
| 864 | |
| 865 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, |
| 866 | unsigned long vlen, loff_t *pos) |
| 867 | { |
| 868 | if (!(file->f_mode & FMODE_READ)) |
| 869 | return -EBADF; |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 870 | if (!(file->f_mode & FMODE_CAN_READ)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 871 | return -EINVAL; |
| 872 | |
| 873 | return do_readv_writev(READ, file, vec, vlen, pos); |
| 874 | } |
| 875 | |
| 876 | EXPORT_SYMBOL(vfs_readv); |
| 877 | |
| 878 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, |
| 879 | unsigned long vlen, loff_t *pos) |
| 880 | { |
| 881 | if (!(file->f_mode & FMODE_WRITE)) |
| 882 | return -EBADF; |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 883 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 884 | return -EINVAL; |
| 885 | |
| 886 | return do_readv_writev(WRITE, file, vec, vlen, pos); |
| 887 | } |
| 888 | |
| 889 | EXPORT_SYMBOL(vfs_writev); |
| 890 | |
Heiko Carstens | 3cdad42 | 2009-01-14 14:14:22 +0100 | [diff] [blame] | 891 | SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, |
| 892 | unsigned long, vlen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 893 | { |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 894 | struct fd f = fdget_pos(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | ssize_t ret = -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 897 | if (f.file) { |
| 898 | loff_t pos = file_pos_read(f.file); |
| 899 | ret = vfs_readv(f.file, vec, vlen, &pos); |
Al Viro | 5faf153 | 2013-06-15 05:49:36 +0400 | [diff] [blame] | 900 | if (ret >= 0) |
| 901 | file_pos_write(f.file, pos); |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 902 | fdput_pos(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 903 | } |
| 904 | |
| 905 | if (ret > 0) |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 906 | add_rchar(current, ret); |
| 907 | inc_syscr(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 908 | return ret; |
| 909 | } |
| 910 | |
Heiko Carstens | 3cdad42 | 2009-01-14 14:14:22 +0100 | [diff] [blame] | 911 | SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, |
| 912 | unsigned long, vlen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | { |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 914 | struct fd f = fdget_pos(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 915 | ssize_t ret = -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 916 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 917 | if (f.file) { |
| 918 | loff_t pos = file_pos_read(f.file); |
| 919 | ret = vfs_writev(f.file, vec, vlen, &pos); |
Al Viro | 5faf153 | 2013-06-15 05:49:36 +0400 | [diff] [blame] | 920 | if (ret >= 0) |
| 921 | file_pos_write(f.file, pos); |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 922 | fdput_pos(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 923 | } |
| 924 | |
| 925 | if (ret > 0) |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 926 | add_wchar(current, ret); |
| 927 | inc_syscw(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 928 | return ret; |
| 929 | } |
| 930 | |
Linus Torvalds | 601cc11 | 2009-04-03 08:03:22 -0700 | [diff] [blame] | 931 | static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 932 | { |
Linus Torvalds | 601cc11 | 2009-04-03 08:03:22 -0700 | [diff] [blame] | 933 | #define HALF_LONG_BITS (BITS_PER_LONG / 2) |
| 934 | return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; |
| 935 | } |
| 936 | |
| 937 | SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, |
| 938 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
| 939 | { |
| 940 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 941 | struct fd f; |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 942 | ssize_t ret = -EBADF; |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 943 | |
| 944 | if (pos < 0) |
| 945 | return -EINVAL; |
| 946 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 947 | f = fdget(fd); |
| 948 | if (f.file) { |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 949 | ret = -ESPIPE; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 950 | if (f.file->f_mode & FMODE_PREAD) |
| 951 | ret = vfs_readv(f.file, vec, vlen, &pos); |
| 952 | fdput(f); |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 953 | } |
| 954 | |
| 955 | if (ret > 0) |
| 956 | add_rchar(current, ret); |
| 957 | inc_syscr(current); |
| 958 | return ret; |
| 959 | } |
| 960 | |
| 961 | SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, |
Linus Torvalds | 601cc11 | 2009-04-03 08:03:22 -0700 | [diff] [blame] | 962 | unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 963 | { |
Linus Torvalds | 601cc11 | 2009-04-03 08:03:22 -0700 | [diff] [blame] | 964 | loff_t pos = pos_from_hilo(pos_h, pos_l); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 965 | struct fd f; |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 966 | ssize_t ret = -EBADF; |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 967 | |
| 968 | if (pos < 0) |
| 969 | return -EINVAL; |
| 970 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 971 | f = fdget(fd); |
| 972 | if (f.file) { |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 973 | ret = -ESPIPE; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 974 | if (f.file->f_mode & FMODE_PWRITE) |
| 975 | ret = vfs_writev(f.file, vec, vlen, &pos); |
| 976 | fdput(f); |
Gerd Hoffmann | f3554f4 | 2009-04-02 16:59:23 -0700 | [diff] [blame] | 977 | } |
| 978 | |
| 979 | if (ret > 0) |
| 980 | add_wchar(current, ret); |
| 981 | inc_syscw(current); |
| 982 | return ret; |
| 983 | } |
| 984 | |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 985 | #ifdef CONFIG_COMPAT |
| 986 | |
| 987 | static ssize_t compat_do_readv_writev(int type, struct file *file, |
| 988 | const struct compat_iovec __user *uvector, |
| 989 | unsigned long nr_segs, loff_t *pos) |
| 990 | { |
| 991 | compat_ssize_t tot_len; |
| 992 | struct iovec iovstack[UIO_FASTIOV]; |
| 993 | struct iovec *iov = iovstack; |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 994 | struct iov_iter iter; |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 995 | ssize_t ret; |
| 996 | io_fn_t fn; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 997 | iter_fn_t iter_fn; |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 998 | |
Al Viro | 0504c07 | 2015-03-21 19:40:11 -0400 | [diff] [blame] | 999 | ret = compat_import_iovec(type, uvector, nr_segs, |
| 1000 | UIO_FASTIOV, &iov, &iter); |
| 1001 | if (ret < 0) |
| 1002 | return ret; |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1003 | |
Al Viro | 0504c07 | 2015-03-21 19:40:11 -0400 | [diff] [blame] | 1004 | tot_len = iov_iter_count(&iter); |
| 1005 | if (!tot_len) |
| 1006 | goto out; |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1007 | ret = rw_verify_area(type, file, pos, tot_len); |
| 1008 | if (ret < 0) |
| 1009 | goto out; |
| 1010 | |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1011 | if (type == READ) { |
| 1012 | fn = file->f_op->read; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 1013 | iter_fn = file->f_op->read_iter; |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1014 | } else { |
| 1015 | fn = (io_fn_t)file->f_op->write; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 1016 | iter_fn = file->f_op->write_iter; |
Al Viro | 03d95eb | 2013-03-20 13:04:20 -0400 | [diff] [blame] | 1017 | file_start_write(file); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1018 | } |
| 1019 | |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 1020 | if (iter_fn) |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 1021 | ret = do_iter_readv_writev(file, &iter, pos, iter_fn); |
Al Viro | 03d95eb | 2013-03-20 13:04:20 -0400 | [diff] [blame] | 1022 | else |
Al Viro | ac15ac0 | 2015-03-20 20:10:21 -0400 | [diff] [blame] | 1023 | ret = do_loop_readv_writev(file, &iter, pos, fn); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1024 | |
Al Viro | 03d95eb | 2013-03-20 13:04:20 -0400 | [diff] [blame] | 1025 | if (type != READ) |
| 1026 | file_end_write(file); |
| 1027 | |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1028 | out: |
Al Viro | 0504c07 | 2015-03-21 19:40:11 -0400 | [diff] [blame] | 1029 | kfree(iov); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1030 | if ((ret + (type == READ)) > 0) { |
| 1031 | if (type == READ) |
| 1032 | fsnotify_access(file); |
| 1033 | else |
| 1034 | fsnotify_modify(file); |
| 1035 | } |
| 1036 | return ret; |
| 1037 | } |
| 1038 | |
| 1039 | static size_t compat_readv(struct file *file, |
| 1040 | const struct compat_iovec __user *vec, |
| 1041 | unsigned long vlen, loff_t *pos) |
| 1042 | { |
| 1043 | ssize_t ret = -EBADF; |
| 1044 | |
| 1045 | if (!(file->f_mode & FMODE_READ)) |
| 1046 | goto out; |
| 1047 | |
| 1048 | ret = -EINVAL; |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 1049 | if (!(file->f_mode & FMODE_CAN_READ)) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1050 | goto out; |
| 1051 | |
| 1052 | ret = compat_do_readv_writev(READ, file, vec, vlen, pos); |
| 1053 | |
| 1054 | out: |
| 1055 | if (ret > 0) |
| 1056 | add_rchar(current, ret); |
| 1057 | inc_syscr(current); |
| 1058 | return ret; |
| 1059 | } |
| 1060 | |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1061 | COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1062 | const struct compat_iovec __user *,vec, |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1063 | compat_ulong_t, vlen) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1064 | { |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 1065 | struct fd f = fdget_pos(fd); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1066 | ssize_t ret; |
| 1067 | loff_t pos; |
| 1068 | |
| 1069 | if (!f.file) |
| 1070 | return -EBADF; |
| 1071 | pos = f.file->f_pos; |
| 1072 | ret = compat_readv(f.file, vec, vlen, &pos); |
Al Viro | 5faf153 | 2013-06-15 05:49:36 +0400 | [diff] [blame] | 1073 | if (ret >= 0) |
| 1074 | f.file->f_pos = pos; |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 1075 | fdput_pos(f); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1076 | return ret; |
| 1077 | } |
| 1078 | |
Heiko Carstens | 378a10f | 2014-03-05 10:43:51 +0100 | [diff] [blame] | 1079 | static long __compat_sys_preadv64(unsigned long fd, |
| 1080 | const struct compat_iovec __user *vec, |
| 1081 | unsigned long vlen, loff_t pos) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1082 | { |
| 1083 | struct fd f; |
| 1084 | ssize_t ret; |
| 1085 | |
| 1086 | if (pos < 0) |
| 1087 | return -EINVAL; |
| 1088 | f = fdget(fd); |
| 1089 | if (!f.file) |
| 1090 | return -EBADF; |
| 1091 | ret = -ESPIPE; |
| 1092 | if (f.file->f_mode & FMODE_PREAD) |
| 1093 | ret = compat_readv(f.file, vec, vlen, &pos); |
| 1094 | fdput(f); |
| 1095 | return ret; |
| 1096 | } |
| 1097 | |
Heiko Carstens | 378a10f | 2014-03-05 10:43:51 +0100 | [diff] [blame] | 1098 | #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64 |
| 1099 | COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, |
| 1100 | const struct compat_iovec __user *,vec, |
| 1101 | unsigned long, vlen, loff_t, pos) |
| 1102 | { |
| 1103 | return __compat_sys_preadv64(fd, vec, vlen, pos); |
| 1104 | } |
| 1105 | #endif |
| 1106 | |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1107 | COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1108 | const struct compat_iovec __user *,vec, |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1109 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1110 | { |
| 1111 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; |
Heiko Carstens | 378a10f | 2014-03-05 10:43:51 +0100 | [diff] [blame] | 1112 | |
| 1113 | return __compat_sys_preadv64(fd, vec, vlen, pos); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1114 | } |
| 1115 | |
| 1116 | static size_t compat_writev(struct file *file, |
| 1117 | const struct compat_iovec __user *vec, |
| 1118 | unsigned long vlen, loff_t *pos) |
| 1119 | { |
| 1120 | ssize_t ret = -EBADF; |
| 1121 | |
| 1122 | if (!(file->f_mode & FMODE_WRITE)) |
| 1123 | goto out; |
| 1124 | |
| 1125 | ret = -EINVAL; |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 1126 | if (!(file->f_mode & FMODE_CAN_WRITE)) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1127 | goto out; |
| 1128 | |
| 1129 | ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos); |
| 1130 | |
| 1131 | out: |
| 1132 | if (ret > 0) |
| 1133 | add_wchar(current, ret); |
| 1134 | inc_syscw(current); |
| 1135 | return ret; |
| 1136 | } |
| 1137 | |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1138 | COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1139 | const struct compat_iovec __user *, vec, |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1140 | compat_ulong_t, vlen) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1141 | { |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 1142 | struct fd f = fdget_pos(fd); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1143 | ssize_t ret; |
| 1144 | loff_t pos; |
| 1145 | |
| 1146 | if (!f.file) |
| 1147 | return -EBADF; |
| 1148 | pos = f.file->f_pos; |
| 1149 | ret = compat_writev(f.file, vec, vlen, &pos); |
Al Viro | 5faf153 | 2013-06-15 05:49:36 +0400 | [diff] [blame] | 1150 | if (ret >= 0) |
| 1151 | f.file->f_pos = pos; |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 1152 | fdput_pos(f); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1153 | return ret; |
| 1154 | } |
| 1155 | |
Heiko Carstens | 378a10f | 2014-03-05 10:43:51 +0100 | [diff] [blame] | 1156 | static long __compat_sys_pwritev64(unsigned long fd, |
| 1157 | const struct compat_iovec __user *vec, |
| 1158 | unsigned long vlen, loff_t pos) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1159 | { |
| 1160 | struct fd f; |
| 1161 | ssize_t ret; |
| 1162 | |
| 1163 | if (pos < 0) |
| 1164 | return -EINVAL; |
| 1165 | f = fdget(fd); |
| 1166 | if (!f.file) |
| 1167 | return -EBADF; |
| 1168 | ret = -ESPIPE; |
| 1169 | if (f.file->f_mode & FMODE_PWRITE) |
| 1170 | ret = compat_writev(f.file, vec, vlen, &pos); |
| 1171 | fdput(f); |
| 1172 | return ret; |
| 1173 | } |
| 1174 | |
Heiko Carstens | 378a10f | 2014-03-05 10:43:51 +0100 | [diff] [blame] | 1175 | #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64 |
| 1176 | COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, |
| 1177 | const struct compat_iovec __user *,vec, |
| 1178 | unsigned long, vlen, loff_t, pos) |
| 1179 | { |
| 1180 | return __compat_sys_pwritev64(fd, vec, vlen, pos); |
| 1181 | } |
| 1182 | #endif |
| 1183 | |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1184 | COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1185 | const struct compat_iovec __user *,vec, |
Heiko Carstens | dfd948e | 2014-01-29 14:05:44 -0800 | [diff] [blame] | 1186 | compat_ulong_t, vlen, u32, pos_low, u32, pos_high) |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1187 | { |
| 1188 | loff_t pos = ((loff_t)pos_high << 32) | pos_low; |
Heiko Carstens | 378a10f | 2014-03-05 10:43:51 +0100 | [diff] [blame] | 1189 | |
| 1190 | return __compat_sys_pwritev64(fd, vec, vlen, pos); |
Al Viro | 72ec351 | 2013-03-20 10:42:10 -0400 | [diff] [blame] | 1191 | } |
| 1192 | #endif |
| 1193 | |
Al Viro | 19f4fc3 | 2013-02-24 02:17:03 -0500 | [diff] [blame] | 1194 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, |
| 1195 | size_t count, loff_t max) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1196 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1197 | struct fd in, out; |
| 1198 | struct inode *in_inode, *out_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1199 | loff_t pos; |
Al Viro | 7995bd2 | 2013-06-20 18:58:36 +0400 | [diff] [blame] | 1200 | loff_t out_pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1201 | ssize_t retval; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1202 | int fl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1203 | |
| 1204 | /* |
| 1205 | * Get input file, and verify that it is ok.. |
| 1206 | */ |
| 1207 | retval = -EBADF; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1208 | in = fdget(in_fd); |
| 1209 | if (!in.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1210 | goto out; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1211 | if (!(in.file->f_mode & FMODE_READ)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1212 | goto fput_in; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1213 | retval = -ESPIPE; |
Al Viro | 7995bd2 | 2013-06-20 18:58:36 +0400 | [diff] [blame] | 1214 | if (!ppos) { |
| 1215 | pos = in.file->f_pos; |
| 1216 | } else { |
| 1217 | pos = *ppos; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1218 | if (!(in.file->f_mode & FMODE_PREAD)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1219 | goto fput_in; |
Al Viro | 7995bd2 | 2013-06-20 18:58:36 +0400 | [diff] [blame] | 1220 | } |
| 1221 | retval = rw_verify_area(READ, in.file, &pos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 1222 | if (retval < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1223 | goto fput_in; |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 1224 | count = retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1225 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1226 | /* |
| 1227 | * Get output file, and verify that it is ok.. |
| 1228 | */ |
| 1229 | retval = -EBADF; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1230 | out = fdget(out_fd); |
| 1231 | if (!out.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1232 | goto fput_in; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1233 | if (!(out.file->f_mode & FMODE_WRITE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1234 | goto fput_out; |
| 1235 | retval = -EINVAL; |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 1236 | in_inode = file_inode(in.file); |
| 1237 | out_inode = file_inode(out.file); |
Al Viro | 7995bd2 | 2013-06-20 18:58:36 +0400 | [diff] [blame] | 1238 | out_pos = out.file->f_pos; |
| 1239 | retval = rw_verify_area(WRITE, out.file, &out_pos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 1240 | if (retval < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1241 | goto fput_out; |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 1242 | count = retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1243 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1244 | if (!max) |
| 1245 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); |
| 1246 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1247 | if (unlikely(pos + count > max)) { |
| 1248 | retval = -EOVERFLOW; |
| 1249 | if (pos >= max) |
| 1250 | goto fput_out; |
| 1251 | count = max - pos; |
| 1252 | } |
| 1253 | |
Jens Axboe | d96e6e7 | 2007-06-11 12:18:52 +0200 | [diff] [blame] | 1254 | fl = 0; |
Jens Axboe | 534f2aa | 2007-06-01 14:52:37 +0200 | [diff] [blame] | 1255 | #if 0 |
Jens Axboe | d96e6e7 | 2007-06-11 12:18:52 +0200 | [diff] [blame] | 1256 | /* |
| 1257 | * We need to debate whether we can enable this or not. The |
| 1258 | * man page documents EAGAIN return for the output at least, |
| 1259 | * and the application is arguably buggy if it doesn't expect |
| 1260 | * EAGAIN on a non-blocking file descriptor. |
| 1261 | */ |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1262 | if (in.file->f_flags & O_NONBLOCK) |
Jens Axboe | d96e6e7 | 2007-06-11 12:18:52 +0200 | [diff] [blame] | 1263 | fl = SPLICE_F_NONBLOCK; |
Jens Axboe | 534f2aa | 2007-06-01 14:52:37 +0200 | [diff] [blame] | 1264 | #endif |
Al Viro | 50cd2c5 | 2013-05-23 20:10:34 -0400 | [diff] [blame] | 1265 | file_start_write(out.file); |
Al Viro | 7995bd2 | 2013-06-20 18:58:36 +0400 | [diff] [blame] | 1266 | retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl); |
Al Viro | 50cd2c5 | 2013-05-23 20:10:34 -0400 | [diff] [blame] | 1267 | file_end_write(out.file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1268 | |
| 1269 | if (retval > 0) { |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 1270 | add_rchar(current, retval); |
| 1271 | add_wchar(current, retval); |
Scott Wolchok | a68c2f1 | 2012-12-20 15:05:52 -0800 | [diff] [blame] | 1272 | fsnotify_access(in.file); |
| 1273 | fsnotify_modify(out.file); |
Al Viro | 7995bd2 | 2013-06-20 18:58:36 +0400 | [diff] [blame] | 1274 | out.file->f_pos = out_pos; |
| 1275 | if (ppos) |
| 1276 | *ppos = pos; |
| 1277 | else |
| 1278 | in.file->f_pos = pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1279 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1280 | |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 1281 | inc_syscr(current); |
| 1282 | inc_syscw(current); |
Al Viro | 7995bd2 | 2013-06-20 18:58:36 +0400 | [diff] [blame] | 1283 | if (pos > max) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1284 | retval = -EOVERFLOW; |
| 1285 | |
| 1286 | fput_out: |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1287 | fdput(out); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1288 | fput_in: |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 1289 | fdput(in); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1290 | out: |
| 1291 | return retval; |
| 1292 | } |
| 1293 | |
Heiko Carstens | 002c897 | 2009-01-14 14:14:18 +0100 | [diff] [blame] | 1294 | SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, off_t __user *, offset, size_t, count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1295 | { |
| 1296 | loff_t pos; |
| 1297 | off_t off; |
| 1298 | ssize_t ret; |
| 1299 | |
| 1300 | if (offset) { |
| 1301 | if (unlikely(get_user(off, offset))) |
| 1302 | return -EFAULT; |
| 1303 | pos = off; |
| 1304 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); |
| 1305 | if (unlikely(put_user(pos, offset))) |
| 1306 | return -EFAULT; |
| 1307 | return ret; |
| 1308 | } |
| 1309 | |
| 1310 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
| 1311 | } |
| 1312 | |
Heiko Carstens | 002c897 | 2009-01-14 14:14:18 +0100 | [diff] [blame] | 1313 | SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, size_t, count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1314 | { |
| 1315 | loff_t pos; |
| 1316 | ssize_t ret; |
| 1317 | |
| 1318 | if (offset) { |
| 1319 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) |
| 1320 | return -EFAULT; |
| 1321 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); |
| 1322 | if (unlikely(put_user(pos, offset))) |
| 1323 | return -EFAULT; |
| 1324 | return ret; |
| 1325 | } |
| 1326 | |
| 1327 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
| 1328 | } |
Al Viro | 19f4fc3 | 2013-02-24 02:17:03 -0500 | [diff] [blame] | 1329 | |
| 1330 | #ifdef CONFIG_COMPAT |
| 1331 | COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, |
| 1332 | compat_off_t __user *, offset, compat_size_t, count) |
| 1333 | { |
| 1334 | loff_t pos; |
| 1335 | off_t off; |
| 1336 | ssize_t ret; |
| 1337 | |
| 1338 | if (offset) { |
| 1339 | if (unlikely(get_user(off, offset))) |
| 1340 | return -EFAULT; |
| 1341 | pos = off; |
| 1342 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); |
| 1343 | if (unlikely(put_user(pos, offset))) |
| 1344 | return -EFAULT; |
| 1345 | return ret; |
| 1346 | } |
| 1347 | |
| 1348 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
| 1349 | } |
| 1350 | |
| 1351 | COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, |
| 1352 | compat_loff_t __user *, offset, compat_size_t, count) |
| 1353 | { |
| 1354 | loff_t pos; |
| 1355 | ssize_t ret; |
| 1356 | |
| 1357 | if (offset) { |
| 1358 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) |
| 1359 | return -EFAULT; |
| 1360 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); |
| 1361 | if (unlikely(put_user(pos, offset))) |
| 1362 | return -EFAULT; |
| 1363 | return ret; |
| 1364 | } |
| 1365 | |
| 1366 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
| 1367 | } |
| 1368 | #endif |