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> |
| 12 | #include <linux/smp_lock.h> |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 13 | #include <linux/fsnotify.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/security.h> |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/syscalls.h> |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 17 | #include <linux/pagemap.h> |
Jens Axboe | d6b29d7 | 2007-06-04 09:59:47 +0200 | [diff] [blame] | 18 | #include <linux/splice.h> |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 19 | #include "read_write.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 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 24 | const struct file_operations generic_ro_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | .llseek = generic_file_llseek, |
Badari Pulavarty | 543ade1 | 2006-09-30 23:28:48 -0700 | [diff] [blame] | 26 | .read = do_sync_read, |
| 27 | .aio_read = generic_file_aio_read, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | .mmap = generic_file_readonly_mmap, |
Jens Axboe | 534f2aa | 2007-06-01 14:52:37 +0200 | [diff] [blame] | 29 | .splice_read = generic_file_splice_read, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | }; |
| 31 | |
| 32 | EXPORT_SYMBOL(generic_ro_fops); |
| 33 | |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 34 | /** |
| 35 | * generic_file_llseek_unlocked - lockless generic llseek implementation |
| 36 | * @file: file structure to seek on |
| 37 | * @offset: file offset to seek to |
| 38 | * @origin: type of seek |
| 39 | * |
| 40 | * Updates the file offset to the value specified by @offset and @origin. |
| 41 | * Locking must be provided by the caller. |
| 42 | */ |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 43 | loff_t |
| 44 | generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | struct inode *inode = file->f_mapping->host; |
| 47 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | switch (origin) { |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 49 | case SEEK_END: |
| 50 | offset += inode->i_size; |
| 51 | break; |
| 52 | case SEEK_CUR: |
Alain Knaff | 5b6f1eb | 2008-11-10 17:08:08 -0800 | [diff] [blame] | 53 | /* |
| 54 | * Here we special-case the lseek(fd, 0, SEEK_CUR) |
| 55 | * position-querying operation. Avoid rewriting the "same" |
| 56 | * f_pos value back to the file because a concurrent read(), |
| 57 | * write() or lseek() might have altered it |
| 58 | */ |
| 59 | if (offset == 0) |
| 60 | return file->f_pos; |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 61 | offset += file->f_pos; |
| 62 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | } |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 64 | |
| 65 | if (offset < 0 || offset > inode->i_sb->s_maxbytes) |
| 66 | return -EINVAL; |
| 67 | |
| 68 | /* Special lock needed here? */ |
| 69 | if (offset != file->f_pos) { |
| 70 | file->f_pos = offset; |
| 71 | file->f_version = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | } |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 73 | |
| 74 | return offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | } |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 76 | EXPORT_SYMBOL(generic_file_llseek_unlocked); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 78 | /** |
| 79 | * generic_file_llseek - generic llseek implementation for regular files |
| 80 | * @file: file structure to seek on |
| 81 | * @offset: file offset to seek to |
| 82 | * @origin: type of seek |
| 83 | * |
| 84 | * This is a generic implemenation of ->llseek useable for all normal local |
| 85 | * filesystems. It just updates the file offset to the value specified by |
| 86 | * @offset and @origin under i_mutex. |
| 87 | */ |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 88 | loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | { |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 90 | loff_t rval; |
| 91 | |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 92 | mutex_lock(&file->f_dentry->d_inode->i_mutex); |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 93 | rval = generic_file_llseek_unlocked(file, offset, origin); |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 94 | mutex_unlock(&file->f_dentry->d_inode->i_mutex); |
Christoph Hellwig | 3a8cff4 | 2008-08-11 15:37:17 +0200 | [diff] [blame] | 95 | |
| 96 | return rval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | } |
Andi Kleen | 9465efc | 2008-06-27 11:05:24 +0200 | [diff] [blame] | 98 | EXPORT_SYMBOL(generic_file_llseek); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | |
| 100 | loff_t no_llseek(struct file *file, loff_t offset, int origin) |
| 101 | { |
| 102 | return -ESPIPE; |
| 103 | } |
| 104 | EXPORT_SYMBOL(no_llseek); |
| 105 | |
| 106 | loff_t default_llseek(struct file *file, loff_t offset, int origin) |
| 107 | { |
David Sterba | 16abef0 | 2008-04-22 15:09:22 +0200 | [diff] [blame] | 108 | loff_t retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | |
| 110 | lock_kernel(); |
| 111 | switch (origin) { |
Chris Snook | 7b8e892 | 2007-05-08 00:24:13 -0700 | [diff] [blame] | 112 | case SEEK_END: |
Josef "Jeff" Sipek | 0f7fc9e | 2006-12-08 02:36:35 -0800 | [diff] [blame] | 113 | offset += i_size_read(file->f_path.dentry->d_inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | break; |
Chris Snook | 7b8e892 | 2007-05-08 00:24:13 -0700 | [diff] [blame] | 115 | case SEEK_CUR: |
Alain Knaff | 5b6f1eb | 2008-11-10 17:08:08 -0800 | [diff] [blame] | 116 | if (offset == 0) { |
| 117 | retval = file->f_pos; |
| 118 | goto out; |
| 119 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | offset += file->f_pos; |
| 121 | } |
| 122 | retval = -EINVAL; |
| 123 | if (offset >= 0) { |
| 124 | if (offset != file->f_pos) { |
| 125 | file->f_pos = offset; |
| 126 | file->f_version = 0; |
| 127 | } |
| 128 | retval = offset; |
| 129 | } |
Alain Knaff | 5b6f1eb | 2008-11-10 17:08:08 -0800 | [diff] [blame] | 130 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | unlock_kernel(); |
| 132 | return retval; |
| 133 | } |
| 134 | EXPORT_SYMBOL(default_llseek); |
| 135 | |
| 136 | loff_t vfs_llseek(struct file *file, loff_t offset, int origin) |
| 137 | { |
| 138 | loff_t (*fn)(struct file *, loff_t, int); |
| 139 | |
| 140 | fn = no_llseek; |
| 141 | if (file->f_mode & FMODE_LSEEK) { |
| 142 | fn = default_llseek; |
| 143 | if (file->f_op && file->f_op->llseek) |
| 144 | fn = file->f_op->llseek; |
| 145 | } |
| 146 | return fn(file, offset, origin); |
| 147 | } |
| 148 | EXPORT_SYMBOL(vfs_llseek); |
| 149 | |
Heiko Carstens | 2ed7c03 | 2009-01-14 14:13:54 +0100 | [diff] [blame] | 150 | asmlinkage long sys_lseek(unsigned int fd, off_t offset, unsigned int origin) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | { |
| 152 | off_t retval; |
| 153 | struct file * file; |
| 154 | int fput_needed; |
| 155 | |
| 156 | retval = -EBADF; |
| 157 | file = fget_light(fd, &fput_needed); |
| 158 | if (!file) |
| 159 | goto bad; |
| 160 | |
| 161 | retval = -EINVAL; |
Chris Snook | 1ae7075 | 2007-05-08 00:24:15 -0700 | [diff] [blame] | 162 | if (origin <= SEEK_MAX) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | loff_t res = vfs_llseek(file, offset, origin); |
| 164 | retval = res; |
| 165 | if (res != (loff_t)retval) |
| 166 | retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ |
| 167 | } |
| 168 | fput_light(file, fput_needed); |
| 169 | bad: |
| 170 | return retval; |
| 171 | } |
| 172 | |
| 173 | #ifdef __ARCH_WANT_SYS_LLSEEK |
| 174 | asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high, |
| 175 | unsigned long offset_low, loff_t __user * result, |
| 176 | unsigned int origin) |
| 177 | { |
| 178 | int retval; |
| 179 | struct file * file; |
| 180 | loff_t offset; |
| 181 | int fput_needed; |
| 182 | |
| 183 | retval = -EBADF; |
| 184 | file = fget_light(fd, &fput_needed); |
| 185 | if (!file) |
| 186 | goto bad; |
| 187 | |
| 188 | retval = -EINVAL; |
Chris Snook | 1ae7075 | 2007-05-08 00:24:15 -0700 | [diff] [blame] | 189 | if (origin > SEEK_MAX) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | goto out_putf; |
| 191 | |
| 192 | offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low, |
| 193 | origin); |
| 194 | |
| 195 | retval = (int)offset; |
| 196 | if (offset >= 0) { |
| 197 | retval = -EFAULT; |
| 198 | if (!copy_to_user(result, &offset, sizeof(offset))) |
| 199 | retval = 0; |
| 200 | } |
| 201 | out_putf: |
| 202 | fput_light(file, fput_needed); |
| 203 | bad: |
| 204 | return retval; |
| 205 | } |
| 206 | #endif |
| 207 | |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 208 | /* |
| 209 | * rw_verify_area doesn't like huge counts. We limit |
| 210 | * them to something that fits in "int" so that others |
| 211 | * won't have to do range checks all the time. |
| 212 | */ |
| 213 | #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | |
| 215 | int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count) |
| 216 | { |
| 217 | struct inode *inode; |
| 218 | loff_t pos; |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 219 | int retval = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | |
Eric Dumazet | 163da95 | 2007-02-12 00:52:24 -0800 | [diff] [blame] | 221 | inode = file->f_path.dentry->d_inode; |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 222 | if (unlikely((ssize_t) count < 0)) |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 223 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | pos = *ppos; |
| 225 | if (unlikely((pos < 0) || (loff_t) (pos + count) < 0)) |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 226 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | |
Pavel Emelyanov | a16877c | 2007-10-01 14:41:11 -0700 | [diff] [blame] | 228 | if (unlikely(inode->i_flock && mandatory_lock(inode))) { |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 229 | retval = locks_mandatory_area( |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 230 | read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, |
| 231 | inode, file, pos, count); |
| 232 | if (retval < 0) |
| 233 | return retval; |
| 234 | } |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 235 | retval = security_file_permission(file, |
| 236 | read_write == READ ? MAY_READ : MAY_WRITE); |
| 237 | if (retval) |
| 238 | return retval; |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 239 | return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | } |
| 241 | |
Benjamin LaHaise | 63e6880 | 2005-06-23 00:10:27 -0700 | [diff] [blame] | 242 | static void wait_on_retry_sync_kiocb(struct kiocb *iocb) |
| 243 | { |
| 244 | set_current_state(TASK_UNINTERRUPTIBLE); |
| 245 | if (!kiocbIsKicked(iocb)) |
| 246 | schedule(); |
| 247 | else |
| 248 | kiocbClearKicked(iocb); |
| 249 | __set_current_state(TASK_RUNNING); |
| 250 | } |
| 251 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) |
| 253 | { |
Badari Pulavarty | 027445c | 2006-09-30 23:28:46 -0700 | [diff] [blame] | 254 | struct iovec iov = { .iov_base = buf, .iov_len = len }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | struct kiocb kiocb; |
| 256 | ssize_t ret; |
| 257 | |
| 258 | init_sync_kiocb(&kiocb, filp); |
| 259 | kiocb.ki_pos = *ppos; |
Badari Pulavarty | 027445c | 2006-09-30 23:28:46 -0700 | [diff] [blame] | 260 | kiocb.ki_left = len; |
| 261 | |
| 262 | for (;;) { |
| 263 | ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); |
| 264 | if (ret != -EIOCBRETRY) |
| 265 | break; |
Benjamin LaHaise | 63e6880 | 2005-06-23 00:10:27 -0700 | [diff] [blame] | 266 | wait_on_retry_sync_kiocb(&kiocb); |
Badari Pulavarty | 027445c | 2006-09-30 23:28:46 -0700 | [diff] [blame] | 267 | } |
Benjamin LaHaise | 63e6880 | 2005-06-23 00:10:27 -0700 | [diff] [blame] | 268 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | if (-EIOCBQUEUED == ret) |
| 270 | ret = wait_on_sync_kiocb(&kiocb); |
| 271 | *ppos = kiocb.ki_pos; |
| 272 | return ret; |
| 273 | } |
| 274 | |
| 275 | EXPORT_SYMBOL(do_sync_read); |
| 276 | |
| 277 | ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) |
| 278 | { |
| 279 | ssize_t ret; |
| 280 | |
| 281 | if (!(file->f_mode & FMODE_READ)) |
| 282 | return -EBADF; |
| 283 | if (!file->f_op || (!file->f_op->read && !file->f_op->aio_read)) |
| 284 | return -EINVAL; |
| 285 | if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) |
| 286 | return -EFAULT; |
| 287 | |
| 288 | ret = rw_verify_area(READ, file, pos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 289 | if (ret >= 0) { |
| 290 | count = ret; |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 291 | if (file->f_op->read) |
| 292 | ret = file->f_op->read(file, buf, count, pos); |
| 293 | else |
| 294 | ret = do_sync_read(file, buf, count, pos); |
| 295 | if (ret > 0) { |
| 296 | fsnotify_access(file->f_path.dentry); |
| 297 | add_rchar(current, ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | } |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 299 | inc_syscr(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | } |
| 301 | |
| 302 | return ret; |
| 303 | } |
| 304 | |
| 305 | EXPORT_SYMBOL(vfs_read); |
| 306 | |
| 307 | ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) |
| 308 | { |
Badari Pulavarty | 027445c | 2006-09-30 23:28:46 -0700 | [diff] [blame] | 309 | struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | struct kiocb kiocb; |
| 311 | ssize_t ret; |
| 312 | |
| 313 | init_sync_kiocb(&kiocb, filp); |
| 314 | kiocb.ki_pos = *ppos; |
Badari Pulavarty | 027445c | 2006-09-30 23:28:46 -0700 | [diff] [blame] | 315 | kiocb.ki_left = len; |
| 316 | |
| 317 | for (;;) { |
| 318 | ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); |
| 319 | if (ret != -EIOCBRETRY) |
| 320 | break; |
Benjamin LaHaise | 63e6880 | 2005-06-23 00:10:27 -0700 | [diff] [blame] | 321 | wait_on_retry_sync_kiocb(&kiocb); |
Badari Pulavarty | 027445c | 2006-09-30 23:28:46 -0700 | [diff] [blame] | 322 | } |
Benjamin LaHaise | 63e6880 | 2005-06-23 00:10:27 -0700 | [diff] [blame] | 323 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | if (-EIOCBQUEUED == ret) |
| 325 | ret = wait_on_sync_kiocb(&kiocb); |
| 326 | *ppos = kiocb.ki_pos; |
| 327 | return ret; |
| 328 | } |
| 329 | |
| 330 | EXPORT_SYMBOL(do_sync_write); |
| 331 | |
| 332 | ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
| 333 | { |
| 334 | ssize_t ret; |
| 335 | |
| 336 | if (!(file->f_mode & FMODE_WRITE)) |
| 337 | return -EBADF; |
| 338 | if (!file->f_op || (!file->f_op->write && !file->f_op->aio_write)) |
| 339 | return -EINVAL; |
| 340 | if (unlikely(!access_ok(VERIFY_READ, buf, count))) |
| 341 | return -EFAULT; |
| 342 | |
| 343 | ret = rw_verify_area(WRITE, file, pos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 344 | if (ret >= 0) { |
| 345 | count = ret; |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 346 | if (file->f_op->write) |
| 347 | ret = file->f_op->write(file, buf, count, pos); |
| 348 | else |
| 349 | ret = do_sync_write(file, buf, count, pos); |
| 350 | if (ret > 0) { |
| 351 | fsnotify_modify(file->f_path.dentry); |
| 352 | add_wchar(current, ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | } |
James Morris | c43e259 | 2008-01-12 22:05:48 +1100 | [diff] [blame] | 354 | inc_syscw(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | } |
| 356 | |
| 357 | return ret; |
| 358 | } |
| 359 | |
| 360 | EXPORT_SYMBOL(vfs_write); |
| 361 | |
| 362 | static inline loff_t file_pos_read(struct file *file) |
| 363 | { |
| 364 | return file->f_pos; |
| 365 | } |
| 366 | |
| 367 | static inline void file_pos_write(struct file *file, loff_t pos) |
| 368 | { |
| 369 | file->f_pos = pos; |
| 370 | } |
| 371 | |
Heiko Carstens | 2ed7c03 | 2009-01-14 14:13:54 +0100 | [diff] [blame] | 372 | asmlinkage long sys_read(unsigned int fd, char __user * buf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | { |
| 374 | struct file *file; |
| 375 | ssize_t ret = -EBADF; |
| 376 | int fput_needed; |
| 377 | |
| 378 | file = fget_light(fd, &fput_needed); |
| 379 | if (file) { |
| 380 | loff_t pos = file_pos_read(file); |
| 381 | ret = vfs_read(file, buf, count, &pos); |
| 382 | file_pos_write(file, pos); |
| 383 | fput_light(file, fput_needed); |
| 384 | } |
| 385 | |
| 386 | return ret; |
| 387 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | |
Heiko Carstens | 2ed7c03 | 2009-01-14 14:13:54 +0100 | [diff] [blame] | 389 | asmlinkage long sys_write(unsigned int fd, const char __user * buf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | { |
| 391 | struct file *file; |
| 392 | ssize_t ret = -EBADF; |
| 393 | int fput_needed; |
| 394 | |
| 395 | file = fget_light(fd, &fput_needed); |
| 396 | if (file) { |
| 397 | loff_t pos = file_pos_read(file); |
| 398 | ret = vfs_write(file, buf, count, &pos); |
| 399 | file_pos_write(file, pos); |
| 400 | fput_light(file, fput_needed); |
| 401 | } |
| 402 | |
| 403 | return ret; |
| 404 | } |
| 405 | |
Heiko Carstens | 6673e0c | 2009-01-14 14:14:02 +0100 | [diff] [blame^] | 406 | SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf, |
| 407 | size_t count, loff_t pos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | { |
| 409 | struct file *file; |
| 410 | ssize_t ret = -EBADF; |
| 411 | int fput_needed; |
| 412 | |
| 413 | if (pos < 0) |
| 414 | return -EINVAL; |
| 415 | |
| 416 | file = fget_light(fd, &fput_needed); |
| 417 | if (file) { |
| 418 | ret = -ESPIPE; |
| 419 | if (file->f_mode & FMODE_PREAD) |
| 420 | ret = vfs_read(file, buf, count, &pos); |
| 421 | fput_light(file, fput_needed); |
| 422 | } |
| 423 | |
| 424 | return ret; |
| 425 | } |
Heiko Carstens | 6673e0c | 2009-01-14 14:14:02 +0100 | [diff] [blame^] | 426 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
| 427 | asmlinkage long SyS_pread64(long fd, long buf, long count, loff_t pos) |
| 428 | { |
| 429 | return SYSC_pread64((unsigned int) fd, (char __user *) buf, |
| 430 | (size_t) count, pos); |
| 431 | } |
| 432 | SYSCALL_ALIAS(sys_pread64, SyS_pread64); |
| 433 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | |
Heiko Carstens | 6673e0c | 2009-01-14 14:14:02 +0100 | [diff] [blame^] | 435 | SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf, |
| 436 | size_t count, loff_t pos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | { |
| 438 | struct file *file; |
| 439 | ssize_t ret = -EBADF; |
| 440 | int fput_needed; |
| 441 | |
| 442 | if (pos < 0) |
| 443 | return -EINVAL; |
| 444 | |
| 445 | file = fget_light(fd, &fput_needed); |
| 446 | if (file) { |
| 447 | ret = -ESPIPE; |
| 448 | if (file->f_mode & FMODE_PWRITE) |
| 449 | ret = vfs_write(file, buf, count, &pos); |
| 450 | fput_light(file, fput_needed); |
| 451 | } |
| 452 | |
| 453 | return ret; |
| 454 | } |
Heiko Carstens | 6673e0c | 2009-01-14 14:14:02 +0100 | [diff] [blame^] | 455 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
| 456 | asmlinkage long SyS_pwrite64(long fd, long buf, long count, loff_t pos) |
| 457 | { |
| 458 | return SYSC_pwrite64((unsigned int) fd, (const char __user *) buf, |
| 459 | (size_t) count, pos); |
| 460 | } |
| 461 | SYSCALL_ALIAS(sys_pwrite64, SyS_pwrite64); |
| 462 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | |
| 464 | /* |
| 465 | * Reduce an iovec's length in-place. Return the resulting number of segments |
| 466 | */ |
| 467 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) |
| 468 | { |
| 469 | unsigned long seg = 0; |
| 470 | size_t len = 0; |
| 471 | |
| 472 | while (seg < nr_segs) { |
| 473 | seg++; |
| 474 | if (len + iov->iov_len >= to) { |
| 475 | iov->iov_len = to - len; |
| 476 | break; |
| 477 | } |
| 478 | len += iov->iov_len; |
| 479 | iov++; |
| 480 | } |
| 481 | return seg; |
| 482 | } |
Eric Sandeen | 1929552 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 483 | EXPORT_SYMBOL(iov_shorten); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 485 | ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, |
| 486 | unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) |
| 487 | { |
| 488 | struct kiocb kiocb; |
| 489 | ssize_t ret; |
| 490 | |
| 491 | init_sync_kiocb(&kiocb, filp); |
| 492 | kiocb.ki_pos = *ppos; |
| 493 | kiocb.ki_left = len; |
| 494 | kiocb.ki_nbytes = len; |
| 495 | |
| 496 | for (;;) { |
| 497 | ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); |
| 498 | if (ret != -EIOCBRETRY) |
| 499 | break; |
| 500 | wait_on_retry_sync_kiocb(&kiocb); |
| 501 | } |
| 502 | |
| 503 | if (ret == -EIOCBQUEUED) |
| 504 | ret = wait_on_sync_kiocb(&kiocb); |
| 505 | *ppos = kiocb.ki_pos; |
| 506 | return ret; |
| 507 | } |
| 508 | |
| 509 | /* Do it by hand, with file-ops */ |
| 510 | ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, |
| 511 | unsigned long nr_segs, loff_t *ppos, io_fn_t fn) |
| 512 | { |
| 513 | struct iovec *vector = iov; |
| 514 | ssize_t ret = 0; |
| 515 | |
| 516 | while (nr_segs > 0) { |
| 517 | void __user *base; |
| 518 | size_t len; |
| 519 | ssize_t nr; |
| 520 | |
| 521 | base = vector->iov_base; |
| 522 | len = vector->iov_len; |
| 523 | vector++; |
| 524 | nr_segs--; |
| 525 | |
| 526 | nr = fn(filp, base, len, ppos); |
| 527 | |
| 528 | if (nr < 0) { |
| 529 | if (!ret) |
| 530 | ret = nr; |
| 531 | break; |
| 532 | } |
| 533 | ret += nr; |
| 534 | if (nr != len) |
| 535 | break; |
| 536 | } |
| 537 | |
| 538 | return ret; |
| 539 | } |
| 540 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 541 | /* A write operation does a read from user space and vice versa */ |
| 542 | #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) |
| 543 | |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 544 | ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, |
| 545 | unsigned long nr_segs, unsigned long fast_segs, |
| 546 | struct iovec *fast_pointer, |
| 547 | struct iovec **ret_pointer) |
| 548 | { |
| 549 | unsigned long seg; |
| 550 | ssize_t ret; |
| 551 | struct iovec *iov = fast_pointer; |
| 552 | |
| 553 | /* |
| 554 | * SuS says "The readv() function *may* fail if the iovcnt argument |
| 555 | * was less than or equal to 0, or greater than {IOV_MAX}. Linux has |
| 556 | * traditionally returned zero for zero segments, so... |
| 557 | */ |
| 558 | if (nr_segs == 0) { |
| 559 | ret = 0; |
| 560 | goto out; |
| 561 | } |
| 562 | |
| 563 | /* |
| 564 | * First get the "struct iovec" from user memory and |
| 565 | * verify all the pointers |
| 566 | */ |
| 567 | if (nr_segs > UIO_MAXIOV) { |
| 568 | ret = -EINVAL; |
| 569 | goto out; |
| 570 | } |
| 571 | if (nr_segs > fast_segs) { |
| 572 | iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); |
| 573 | if (iov == NULL) { |
| 574 | ret = -ENOMEM; |
| 575 | goto out; |
| 576 | } |
| 577 | } |
| 578 | if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { |
| 579 | ret = -EFAULT; |
| 580 | goto out; |
| 581 | } |
| 582 | |
| 583 | /* |
| 584 | * According to the Single Unix Specification we should return EINVAL |
| 585 | * if an element length is < 0 when cast to ssize_t or if the |
| 586 | * total length would overflow the ssize_t return value of the |
| 587 | * system call. |
| 588 | */ |
| 589 | ret = 0; |
| 590 | for (seg = 0; seg < nr_segs; seg++) { |
| 591 | void __user *buf = iov[seg].iov_base; |
| 592 | ssize_t len = (ssize_t)iov[seg].iov_len; |
| 593 | |
| 594 | /* see if we we're about to use an invalid len or if |
| 595 | * it's about to overflow ssize_t */ |
| 596 | if (len < 0 || (ret + len < ret)) { |
| 597 | ret = -EINVAL; |
| 598 | goto out; |
| 599 | } |
| 600 | if (unlikely(!access_ok(vrfy_dir(type), buf, len))) { |
| 601 | ret = -EFAULT; |
| 602 | goto out; |
| 603 | } |
| 604 | |
| 605 | ret += len; |
| 606 | } |
| 607 | out: |
| 608 | *ret_pointer = iov; |
| 609 | return ret; |
| 610 | } |
| 611 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | static ssize_t do_readv_writev(int type, struct file *file, |
| 613 | const struct iovec __user * uvector, |
| 614 | unsigned long nr_segs, loff_t *pos) |
| 615 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | size_t tot_len; |
| 617 | struct iovec iovstack[UIO_FASTIOV]; |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 618 | struct iovec *iov = iovstack; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 619 | ssize_t ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | io_fn_t fn; |
| 621 | iov_fn_t fnv; |
| 622 | |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 623 | if (!file->f_op) { |
| 624 | ret = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | goto out; |
| 626 | } |
| 627 | |
Badari Pulavarty | eed4e51 | 2006-09-30 23:28:49 -0700 | [diff] [blame] | 628 | ret = rw_copy_check_uvector(type, uvector, nr_segs, |
| 629 | ARRAY_SIZE(iovstack), iovstack, &iov); |
| 630 | if (ret <= 0) |
| 631 | goto out; |
| 632 | |
| 633 | tot_len = ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | ret = rw_verify_area(type, file, pos, tot_len); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 635 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 636 | goto out; |
| 637 | |
| 638 | fnv = NULL; |
| 639 | if (type == READ) { |
| 640 | fn = file->f_op->read; |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 641 | fnv = file->f_op->aio_read; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 642 | } else { |
| 643 | fn = (io_fn_t)file->f_op->write; |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 644 | fnv = file->f_op->aio_write; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | } |
| 646 | |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 647 | if (fnv) |
| 648 | ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, |
| 649 | pos, fnv); |
| 650 | else |
| 651 | ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 652 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | out: |
| 654 | if (iov != iovstack) |
| 655 | kfree(iov); |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 656 | if ((ret + (type == READ)) > 0) { |
| 657 | if (type == READ) |
Josef "Jeff" Sipek | 0f7fc9e | 2006-12-08 02:36:35 -0800 | [diff] [blame] | 658 | fsnotify_access(file->f_path.dentry); |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 659 | else |
Josef "Jeff" Sipek | 0f7fc9e | 2006-12-08 02:36:35 -0800 | [diff] [blame] | 660 | fsnotify_modify(file->f_path.dentry); |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 661 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | } |
| 664 | |
| 665 | ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, |
| 666 | unsigned long vlen, loff_t *pos) |
| 667 | { |
| 668 | if (!(file->f_mode & FMODE_READ)) |
| 669 | return -EBADF; |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 670 | if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | return -EINVAL; |
| 672 | |
| 673 | return do_readv_writev(READ, file, vec, vlen, pos); |
| 674 | } |
| 675 | |
| 676 | EXPORT_SYMBOL(vfs_readv); |
| 677 | |
| 678 | ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, |
| 679 | unsigned long vlen, loff_t *pos) |
| 680 | { |
| 681 | if (!(file->f_mode & FMODE_WRITE)) |
| 682 | return -EBADF; |
Badari Pulavarty | ee0b3e6 | 2006-09-30 23:28:47 -0700 | [diff] [blame] | 683 | if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 684 | return -EINVAL; |
| 685 | |
| 686 | return do_readv_writev(WRITE, file, vec, vlen, pos); |
| 687 | } |
| 688 | |
| 689 | EXPORT_SYMBOL(vfs_writev); |
| 690 | |
Heiko Carstens | 2ed7c03 | 2009-01-14 14:13:54 +0100 | [diff] [blame] | 691 | asmlinkage long |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | sys_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) |
| 693 | { |
| 694 | struct file *file; |
| 695 | ssize_t ret = -EBADF; |
| 696 | int fput_needed; |
| 697 | |
| 698 | file = fget_light(fd, &fput_needed); |
| 699 | if (file) { |
| 700 | loff_t pos = file_pos_read(file); |
| 701 | ret = vfs_readv(file, vec, vlen, &pos); |
| 702 | file_pos_write(file, pos); |
| 703 | fput_light(file, fput_needed); |
| 704 | } |
| 705 | |
| 706 | if (ret > 0) |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 707 | add_rchar(current, ret); |
| 708 | inc_syscr(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | return ret; |
| 710 | } |
| 711 | |
Heiko Carstens | 2ed7c03 | 2009-01-14 14:13:54 +0100 | [diff] [blame] | 712 | asmlinkage long |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | sys_writev(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) |
| 714 | { |
| 715 | struct file *file; |
| 716 | ssize_t ret = -EBADF; |
| 717 | int fput_needed; |
| 718 | |
| 719 | file = fget_light(fd, &fput_needed); |
| 720 | if (file) { |
| 721 | loff_t pos = file_pos_read(file); |
| 722 | ret = vfs_writev(file, vec, vlen, &pos); |
| 723 | file_pos_write(file, pos); |
| 724 | fput_light(file, fput_needed); |
| 725 | } |
| 726 | |
| 727 | if (ret > 0) |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 728 | add_wchar(current, ret); |
| 729 | inc_syscw(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 730 | return ret; |
| 731 | } |
| 732 | |
| 733 | static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, |
| 734 | size_t count, loff_t max) |
| 735 | { |
| 736 | struct file * in_file, * out_file; |
| 737 | struct inode * in_inode, * out_inode; |
| 738 | loff_t pos; |
| 739 | ssize_t retval; |
Jens Axboe | 534f2aa | 2007-06-01 14:52:37 +0200 | [diff] [blame] | 740 | int fput_needed_in, fput_needed_out, fl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 741 | |
| 742 | /* |
| 743 | * Get input file, and verify that it is ok.. |
| 744 | */ |
| 745 | retval = -EBADF; |
| 746 | in_file = fget_light(in_fd, &fput_needed_in); |
| 747 | if (!in_file) |
| 748 | goto out; |
| 749 | if (!(in_file->f_mode & FMODE_READ)) |
| 750 | goto fput_in; |
| 751 | retval = -EINVAL; |
Josef "Jeff" Sipek | 0f7fc9e | 2006-12-08 02:36:35 -0800 | [diff] [blame] | 752 | in_inode = in_file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 753 | if (!in_inode) |
| 754 | goto fput_in; |
Jens Axboe | d96e6e7 | 2007-06-11 12:18:52 +0200 | [diff] [blame] | 755 | if (!in_file->f_op || !in_file->f_op->splice_read) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | goto fput_in; |
| 757 | retval = -ESPIPE; |
| 758 | if (!ppos) |
| 759 | ppos = &in_file->f_pos; |
| 760 | else |
| 761 | if (!(in_file->f_mode & FMODE_PREAD)) |
| 762 | goto fput_in; |
| 763 | retval = rw_verify_area(READ, in_file, ppos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 764 | if (retval < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | goto fput_in; |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 766 | count = retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | /* |
| 769 | * Get output file, and verify that it is ok.. |
| 770 | */ |
| 771 | retval = -EBADF; |
| 772 | out_file = fget_light(out_fd, &fput_needed_out); |
| 773 | if (!out_file) |
| 774 | goto fput_in; |
| 775 | if (!(out_file->f_mode & FMODE_WRITE)) |
| 776 | goto fput_out; |
| 777 | retval = -EINVAL; |
| 778 | if (!out_file->f_op || !out_file->f_op->sendpage) |
| 779 | goto fput_out; |
Josef "Jeff" Sipek | 0f7fc9e | 2006-12-08 02:36:35 -0800 | [diff] [blame] | 780 | out_inode = out_file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 781 | retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 782 | if (retval < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 783 | goto fput_out; |
Linus Torvalds | e28cc71 | 2006-01-04 16:20:40 -0800 | [diff] [blame] | 784 | count = retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 785 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | if (!max) |
| 787 | max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes); |
| 788 | |
| 789 | pos = *ppos; |
| 790 | retval = -EINVAL; |
| 791 | if (unlikely(pos < 0)) |
| 792 | goto fput_out; |
| 793 | if (unlikely(pos + count > max)) { |
| 794 | retval = -EOVERFLOW; |
| 795 | if (pos >= max) |
| 796 | goto fput_out; |
| 797 | count = max - pos; |
| 798 | } |
| 799 | |
Jens Axboe | d96e6e7 | 2007-06-11 12:18:52 +0200 | [diff] [blame] | 800 | fl = 0; |
Jens Axboe | 534f2aa | 2007-06-01 14:52:37 +0200 | [diff] [blame] | 801 | #if 0 |
Jens Axboe | d96e6e7 | 2007-06-11 12:18:52 +0200 | [diff] [blame] | 802 | /* |
| 803 | * We need to debate whether we can enable this or not. The |
| 804 | * man page documents EAGAIN return for the output at least, |
| 805 | * and the application is arguably buggy if it doesn't expect |
| 806 | * EAGAIN on a non-blocking file descriptor. |
| 807 | */ |
| 808 | if (in_file->f_flags & O_NONBLOCK) |
| 809 | fl = SPLICE_F_NONBLOCK; |
Jens Axboe | 534f2aa | 2007-06-01 14:52:37 +0200 | [diff] [blame] | 810 | #endif |
Jens Axboe | d96e6e7 | 2007-06-11 12:18:52 +0200 | [diff] [blame] | 811 | retval = do_splice_direct(in_file, ppos, out_file, count, fl); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 812 | |
| 813 | if (retval > 0) { |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 814 | add_rchar(current, retval); |
| 815 | add_wchar(current, retval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | |
Alexey Dobriyan | 4b98d11 | 2007-02-10 01:46:45 -0800 | [diff] [blame] | 818 | inc_syscr(current); |
| 819 | inc_syscw(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | if (*ppos > max) |
| 821 | retval = -EOVERFLOW; |
| 822 | |
| 823 | fput_out: |
| 824 | fput_light(out_file, fput_needed_out); |
| 825 | fput_in: |
| 826 | fput_light(in_file, fput_needed_in); |
| 827 | out: |
| 828 | return retval; |
| 829 | } |
| 830 | |
Heiko Carstens | 2ed7c03 | 2009-01-14 14:13:54 +0100 | [diff] [blame] | 831 | asmlinkage long sys_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] | 832 | { |
| 833 | loff_t pos; |
| 834 | off_t off; |
| 835 | ssize_t ret; |
| 836 | |
| 837 | if (offset) { |
| 838 | if (unlikely(get_user(off, offset))) |
| 839 | return -EFAULT; |
| 840 | pos = off; |
| 841 | ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); |
| 842 | if (unlikely(put_user(pos, offset))) |
| 843 | return -EFAULT; |
| 844 | return ret; |
| 845 | } |
| 846 | |
| 847 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
| 848 | } |
| 849 | |
Heiko Carstens | 2ed7c03 | 2009-01-14 14:13:54 +0100 | [diff] [blame] | 850 | asmlinkage long sys_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] | 851 | { |
| 852 | loff_t pos; |
| 853 | ssize_t ret; |
| 854 | |
| 855 | if (offset) { |
| 856 | if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) |
| 857 | return -EFAULT; |
| 858 | ret = do_sendfile(out_fd, in_fd, &pos, count, 0); |
| 859 | if (unlikely(put_user(pos, offset))) |
| 860 | return -EFAULT; |
| 861 | return ret; |
| 862 | } |
| 863 | |
| 864 | return do_sendfile(out_fd, in_fd, NULL, count, 0); |
| 865 | } |