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/smp_lock.h> 16 #include <linux/mount.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 handle = ext4_journal_start(inode, 1); 96 if (IS_ERR(handle)) { 97 err = PTR_ERR(handle); 98 goto flags_out; 99 } 100 if (IS_SYNC(inode)) 101 ext4_handle_sync(handle); 102 err = ext4_reserve_inode_write(handle, inode, &iloc); 103 if (err) 104 goto flags_err; 105 106 flags = flags & EXT4_FL_USER_MODIFIABLE; 107 flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE; 108 ei->i_flags = flags; 109 110 ext4_set_inode_flags(inode); 111 inode->i_ctime = ext4_current_time(inode); 112 113 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 114 flags_err: 115 ext4_journal_stop(handle); 116 if (err) 117 goto flags_out; 118 119 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) 120 err = ext4_change_inode_journal_flag(inode, jflag); 121 if (err) 122 goto flags_out; 123 if (migrate) 124 err = ext4_ext_migrate(inode); 125 flags_out: 126 mutex_unlock(&inode->i_mutex); 127 mnt_drop_write(filp->f_path.mnt); 128 return err; 129 } 130 case EXT4_IOC_GETVERSION: 131 case EXT4_IOC_GETVERSION_OLD: 132 return put_user(inode->i_generation, (int __user *) arg); 133 case EXT4_IOC_SETVERSION: 134 case EXT4_IOC_SETVERSION_OLD: { 135 handle_t *handle; 136 struct ext4_iloc iloc; 137 __u32 generation; 138 int err; 139 140 if (!is_owner_or_cap(inode)) 141 return -EPERM; 142 143 err = mnt_want_write(filp->f_path.mnt); 144 if (err) 145 return err; 146 if (get_user(generation, (int __user *) arg)) { 147 err = -EFAULT; 148 goto setversion_out; 149 } 150 151 handle = ext4_journal_start(inode, 1); 152 if (IS_ERR(handle)) { 153 err = PTR_ERR(handle); 154 goto setversion_out; 155 } 156 err = ext4_reserve_inode_write(handle, inode, &iloc); 157 if (err == 0) { 158 inode->i_ctime = ext4_current_time(inode); 159 inode->i_generation = generation; 160 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 161 } 162 ext4_journal_stop(handle); 163 setversion_out: 164 mnt_drop_write(filp->f_path.mnt); 165 return err; 166 } 167 #ifdef CONFIG_JBD2_DEBUG 168 case EXT4_IOC_WAIT_FOR_READONLY: 169 /* 170 * This is racy - by the time we're woken up and running, 171 * the superblock could be released. And the module could 172 * have been unloaded. So sue me. 173 * 174 * Returns 1 if it slept, else zero. 175 */ 176 { 177 struct super_block *sb = inode->i_sb; 178 DECLARE_WAITQUEUE(wait, current); 179 int ret = 0; 180 181 set_current_state(TASK_INTERRUPTIBLE); 182 add_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait); 183 if (timer_pending(&EXT4_SB(sb)->turn_ro_timer)) { 184 schedule(); 185 ret = 1; 186 } 187 remove_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait); 188 return ret; 189 } 190 #endif 191 case EXT4_IOC_GROUP_EXTEND: { 192 ext4_fsblk_t n_blocks_count; 193 struct super_block *sb = inode->i_sb; 194 int err, err2; 195 196 if (!capable(CAP_SYS_RESOURCE)) 197 return -EPERM; 198 199 if (get_user(n_blocks_count, (__u32 __user *)arg)) 200 return -EFAULT; 201 202 err = mnt_want_write(filp->f_path.mnt); 203 if (err) 204 return err; 205 206 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count); 207 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); 208 err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal); 209 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); 210 if (err == 0) 211 err = err2; 212 mnt_drop_write(filp->f_path.mnt); 213 214 return err; 215 } 216 case EXT4_IOC_GROUP_ADD: { 217 struct ext4_new_group_data input; 218 struct super_block *sb = inode->i_sb; 219 int err, err2; 220 221 if (!capable(CAP_SYS_RESOURCE)) 222 return -EPERM; 223 224 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg, 225 sizeof(input))) 226 return -EFAULT; 227 228 err = mnt_want_write(filp->f_path.mnt); 229 if (err) 230 return err; 231 232 err = ext4_group_add(sb, &input); 233 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); 234 err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal); 235 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); 236 if (err == 0) 237 err = err2; 238 mnt_drop_write(filp->f_path.mnt); 239 240 return err; 241 } 242 243 case EXT4_IOC_MIGRATE: 244 { 245 int err; 246 if (!is_owner_or_cap(inode)) 247 return -EACCES; 248 249 err = mnt_want_write(filp->f_path.mnt); 250 if (err) 251 return err; 252 /* 253 * inode_mutex prevent write and truncate on the file. 254 * Read still goes through. We take i_data_sem in 255 * ext4_ext_swap_inode_data before we switch the 256 * inode format to prevent read. 257 */ 258 mutex_lock(&(inode->i_mutex)); 259 err = ext4_ext_migrate(inode); 260 mutex_unlock(&(inode->i_mutex)); 261 mnt_drop_write(filp->f_path.mnt); 262 return err; 263 } 264 265 case EXT4_IOC_ALLOC_DA_BLKS: 266 { 267 int err; 268 if (!is_owner_or_cap(inode)) 269 return -EACCES; 270 271 err = mnt_want_write(filp->f_path.mnt); 272 if (err) 273 return err; 274 err = ext4_alloc_da_blocks(inode); 275 mnt_drop_write(filp->f_path.mnt); 276 return err; 277 } 278 279 default: 280 return -ENOTTY; 281 } 282 } 283 284 #ifdef CONFIG_COMPAT 285 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 286 { 287 /* These are just misnamed, they actually get/put from/to user an int */ 288 switch (cmd) { 289 case EXT4_IOC32_GETFLAGS: 290 cmd = EXT4_IOC_GETFLAGS; 291 break; 292 case EXT4_IOC32_SETFLAGS: 293 cmd = EXT4_IOC_SETFLAGS; 294 break; 295 case EXT4_IOC32_GETVERSION: 296 cmd = EXT4_IOC_GETVERSION; 297 break; 298 case EXT4_IOC32_SETVERSION: 299 cmd = EXT4_IOC_SETVERSION; 300 break; 301 case EXT4_IOC32_GROUP_EXTEND: 302 cmd = EXT4_IOC_GROUP_EXTEND; 303 break; 304 case EXT4_IOC32_GETVERSION_OLD: 305 cmd = EXT4_IOC_GETVERSION_OLD; 306 break; 307 case EXT4_IOC32_SETVERSION_OLD: 308 cmd = EXT4_IOC_SETVERSION_OLD; 309 break; 310 #ifdef CONFIG_JBD2_DEBUG 311 case EXT4_IOC32_WAIT_FOR_READONLY: 312 cmd = EXT4_IOC_WAIT_FOR_READONLY; 313 break; 314 #endif 315 case EXT4_IOC32_GETRSVSZ: 316 cmd = EXT4_IOC_GETRSVSZ; 317 break; 318 case EXT4_IOC32_SETRSVSZ: 319 cmd = EXT4_IOC_SETRSVSZ; 320 break; 321 case EXT4_IOC_GROUP_ADD: 322 break; 323 default: 324 return -ENOIOCTLCMD; 325 } 326 return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); 327 } 328 #endif 329