1 /* 2 * linux/fs/ext4/ioctl.c 3 * 4 * Copyright (C) 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 */ 9 10 #include <linux/fs.h> 11 #include <linux/jbd2.h> 12 #include <linux/capability.h> 13 #include <linux/time.h> 14 #include <linux/compat.h> 15 #include <linux/mount.h> 16 #include <linux/file.h> 17 #include <asm/uaccess.h> 18 #include "ext4_jbd2.h" 19 #include "ext4.h" 20 21 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 22 { 23 struct inode *inode = filp->f_dentry->d_inode; 24 struct ext4_inode_info *ei = EXT4_I(inode); 25 unsigned int flags; 26 27 ext4_debug("cmd = %u, arg = %lu\n", cmd, arg); 28 29 switch (cmd) { 30 case EXT4_IOC_GETFLAGS: 31 ext4_get_inode_flags(ei); 32 flags = ei->i_flags & EXT4_FL_USER_VISIBLE; 33 return put_user(flags, (int __user *) arg); 34 case EXT4_IOC_SETFLAGS: { 35 handle_t *handle = NULL; 36 int err, migrate = 0; 37 struct ext4_iloc iloc; 38 unsigned int oldflags; 39 unsigned int jflag; 40 41 if (!is_owner_or_cap(inode)) 42 return -EACCES; 43 44 if (get_user(flags, (int __user *) arg)) 45 return -EFAULT; 46 47 err = mnt_want_write(filp->f_path.mnt); 48 if (err) 49 return err; 50 51 flags = ext4_mask_flags(inode->i_mode, flags); 52 53 err = -EPERM; 54 mutex_lock(&inode->i_mutex); 55 /* Is it quota file? Do not allow user to mess with it */ 56 if (IS_NOQUOTA(inode)) 57 goto flags_out; 58 59 oldflags = ei->i_flags; 60 61 /* The JOURNAL_DATA flag is modifiable only by root */ 62 jflag = flags & EXT4_JOURNAL_DATA_FL; 63 64 /* 65 * The IMMUTABLE and APPEND_ONLY flags can only be changed by 66 * the relevant capability. 67 * 68 * This test looks nicer. Thanks to Pauline Middelink 69 */ 70 if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) { 71 if (!capable(CAP_LINUX_IMMUTABLE)) 72 goto flags_out; 73 } 74 75 /* 76 * The JOURNAL_DATA flag can only be changed by 77 * the relevant capability. 78 */ 79 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) { 80 if (!capable(CAP_SYS_RESOURCE)) 81 goto flags_out; 82 } 83 if (oldflags & EXT4_EXTENTS_FL) { 84 /* We don't support clearning extent flags */ 85 if (!(flags & EXT4_EXTENTS_FL)) { 86 err = -EOPNOTSUPP; 87 goto flags_out; 88 } 89 } else if (flags & EXT4_EXTENTS_FL) { 90 /* migrate the file */ 91 migrate = 1; 92 flags &= ~EXT4_EXTENTS_FL; 93 } 94 95 if (flags & EXT4_EOFBLOCKS_FL) { 96 /* we don't support adding EOFBLOCKS flag */ 97 if (!(oldflags & EXT4_EOFBLOCKS_FL)) { 98 err = -EOPNOTSUPP; 99 goto flags_out; 100 } 101 } else if (oldflags & EXT4_EOFBLOCKS_FL) 102 ext4_truncate(inode); 103 104 handle = ext4_journal_start(inode, 1); 105 if (IS_ERR(handle)) { 106 err = PTR_ERR(handle); 107 goto flags_out; 108 } 109 if (IS_SYNC(inode)) 110 ext4_handle_sync(handle); 111 err = ext4_reserve_inode_write(handle, inode, &iloc); 112 if (err) 113 goto flags_err; 114 115 flags = flags & EXT4_FL_USER_MODIFIABLE; 116 flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE; 117 ei->i_flags = flags; 118 119 ext4_set_inode_flags(inode); 120 inode->i_ctime = ext4_current_time(inode); 121 122 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 123 flags_err: 124 ext4_journal_stop(handle); 125 if (err) 126 goto flags_out; 127 128 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) 129 err = ext4_change_inode_journal_flag(inode, jflag); 130 if (err) 131 goto flags_out; 132 if (migrate) 133 err = ext4_ext_migrate(inode); 134 flags_out: 135 mutex_unlock(&inode->i_mutex); 136 mnt_drop_write(filp->f_path.mnt); 137 return err; 138 } 139 case EXT4_IOC_GETVERSION: 140 case EXT4_IOC_GETVERSION_OLD: 141 return put_user(inode->i_generation, (int __user *) arg); 142 case EXT4_IOC_SETVERSION: 143 case EXT4_IOC_SETVERSION_OLD: { 144 handle_t *handle; 145 struct ext4_iloc iloc; 146 __u32 generation; 147 int err; 148 149 if (!is_owner_or_cap(inode)) 150 return -EPERM; 151 152 err = mnt_want_write(filp->f_path.mnt); 153 if (err) 154 return err; 155 if (get_user(generation, (int __user *) arg)) { 156 err = -EFAULT; 157 goto setversion_out; 158 } 159 160 handle = ext4_journal_start(inode, 1); 161 if (IS_ERR(handle)) { 162 err = PTR_ERR(handle); 163 goto setversion_out; 164 } 165 err = ext4_reserve_inode_write(handle, inode, &iloc); 166 if (err == 0) { 167 inode->i_ctime = ext4_current_time(inode); 168 inode->i_generation = generation; 169 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 170 } 171 ext4_journal_stop(handle); 172 setversion_out: 173 mnt_drop_write(filp->f_path.mnt); 174 return err; 175 } 176 #ifdef CONFIG_JBD2_DEBUG 177 case EXT4_IOC_WAIT_FOR_READONLY: 178 /* 179 * This is racy - by the time we're woken up and running, 180 * the superblock could be released. And the module could 181 * have been unloaded. So sue me. 182 * 183 * Returns 1 if it slept, else zero. 184 */ 185 { 186 struct super_block *sb = inode->i_sb; 187 DECLARE_WAITQUEUE(wait, current); 188 int ret = 0; 189 190 set_current_state(TASK_INTERRUPTIBLE); 191 add_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait); 192 if (timer_pending(&EXT4_SB(sb)->turn_ro_timer)) { 193 schedule(); 194 ret = 1; 195 } 196 remove_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait); 197 return ret; 198 } 199 #endif 200 case EXT4_IOC_GROUP_EXTEND: { 201 ext4_fsblk_t n_blocks_count; 202 struct super_block *sb = inode->i_sb; 203 int err, err2=0; 204 205 if (!capable(CAP_SYS_RESOURCE)) 206 return -EPERM; 207 208 if (get_user(n_blocks_count, (__u32 __user *)arg)) 209 return -EFAULT; 210 211 err = mnt_want_write(filp->f_path.mnt); 212 if (err) 213 return err; 214 215 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count); 216 if (EXT4_SB(sb)->s_journal) { 217 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); 218 err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal); 219 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); 220 } 221 if (err == 0) 222 err = err2; 223 mnt_drop_write(filp->f_path.mnt); 224 225 return err; 226 } 227 228 case EXT4_IOC_MOVE_EXT: { 229 struct move_extent me; 230 struct file *donor_filp; 231 int err; 232 233 if (!(filp->f_mode & FMODE_READ) || 234 !(filp->f_mode & FMODE_WRITE)) 235 return -EBADF; 236 237 if (copy_from_user(&me, 238 (struct move_extent __user *)arg, sizeof(me))) 239 return -EFAULT; 240 me.moved_len = 0; 241 242 donor_filp = fget(me.donor_fd); 243 if (!donor_filp) 244 return -EBADF; 245 246 if (!(donor_filp->f_mode & FMODE_WRITE)) { 247 err = -EBADF; 248 goto mext_out; 249 } 250 251 err = mnt_want_write(filp->f_path.mnt); 252 if (err) 253 goto mext_out; 254 255 err = ext4_move_extents(filp, donor_filp, me.orig_start, 256 me.donor_start, me.len, &me.moved_len); 257 mnt_drop_write(filp->f_path.mnt); 258 if (me.moved_len > 0) 259 file_remove_suid(donor_filp); 260 261 if (copy_to_user((struct move_extent *)arg, &me, sizeof(me))) 262 err = -EFAULT; 263 mext_out: 264 fput(donor_filp); 265 return err; 266 } 267 268 case EXT4_IOC_GROUP_ADD: { 269 struct ext4_new_group_data input; 270 struct super_block *sb = inode->i_sb; 271 int err, err2=0; 272 273 if (!capable(CAP_SYS_RESOURCE)) 274 return -EPERM; 275 276 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg, 277 sizeof(input))) 278 return -EFAULT; 279 280 err = mnt_want_write(filp->f_path.mnt); 281 if (err) 282 return err; 283 284 err = ext4_group_add(sb, &input); 285 if (EXT4_SB(sb)->s_journal) { 286 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); 287 err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal); 288 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); 289 } 290 if (err == 0) 291 err = err2; 292 mnt_drop_write(filp->f_path.mnt); 293 294 return err; 295 } 296 297 case EXT4_IOC_MIGRATE: 298 { 299 int err; 300 if (!is_owner_or_cap(inode)) 301 return -EACCES; 302 303 err = mnt_want_write(filp->f_path.mnt); 304 if (err) 305 return err; 306 /* 307 * inode_mutex prevent write and truncate on the file. 308 * Read still goes through. We take i_data_sem in 309 * ext4_ext_swap_inode_data before we switch the 310 * inode format to prevent read. 311 */ 312 mutex_lock(&(inode->i_mutex)); 313 err = ext4_ext_migrate(inode); 314 mutex_unlock(&(inode->i_mutex)); 315 mnt_drop_write(filp->f_path.mnt); 316 return err; 317 } 318 319 case EXT4_IOC_ALLOC_DA_BLKS: 320 { 321 int err; 322 if (!is_owner_or_cap(inode)) 323 return -EACCES; 324 325 err = mnt_want_write(filp->f_path.mnt); 326 if (err) 327 return err; 328 err = ext4_alloc_da_blocks(inode); 329 mnt_drop_write(filp->f_path.mnt); 330 return err; 331 } 332 333 default: 334 return -ENOTTY; 335 } 336 } 337 338 #ifdef CONFIG_COMPAT 339 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 340 { 341 /* These are just misnamed, they actually get/put from/to user an int */ 342 switch (cmd) { 343 case EXT4_IOC32_GETFLAGS: 344 cmd = EXT4_IOC_GETFLAGS; 345 break; 346 case EXT4_IOC32_SETFLAGS: 347 cmd = EXT4_IOC_SETFLAGS; 348 break; 349 case EXT4_IOC32_GETVERSION: 350 cmd = EXT4_IOC_GETVERSION; 351 break; 352 case EXT4_IOC32_SETVERSION: 353 cmd = EXT4_IOC_SETVERSION; 354 break; 355 case EXT4_IOC32_GROUP_EXTEND: 356 cmd = EXT4_IOC_GROUP_EXTEND; 357 break; 358 case EXT4_IOC32_GETVERSION_OLD: 359 cmd = EXT4_IOC_GETVERSION_OLD; 360 break; 361 case EXT4_IOC32_SETVERSION_OLD: 362 cmd = EXT4_IOC_SETVERSION_OLD; 363 break; 364 #ifdef CONFIG_JBD2_DEBUG 365 case EXT4_IOC32_WAIT_FOR_READONLY: 366 cmd = EXT4_IOC_WAIT_FOR_READONLY; 367 break; 368 #endif 369 case EXT4_IOC32_GETRSVSZ: 370 cmd = EXT4_IOC_GETRSVSZ; 371 break; 372 case EXT4_IOC32_SETRSVSZ: 373 cmd = EXT4_IOC_SETRSVSZ; 374 break; 375 case EXT4_IOC_GROUP_ADD: 376 break; 377 default: 378 return -ENOIOCTLCMD; 379 } 380 return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); 381 } 382 #endif 383