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 if (!S_ISDIR(inode->i_mode)) 52 flags &= ~EXT4_DIRSYNC_FL; 53 54 err = -EPERM; 55 mutex_lock(&inode->i_mutex); 56 /* Is it quota file? Do not allow user to mess with it */ 57 if (IS_NOQUOTA(inode)) 58 goto flags_out; 59 60 oldflags = ei->i_flags; 61 62 /* The JOURNAL_DATA flag is modifiable only by root */ 63 jflag = flags & EXT4_JOURNAL_DATA_FL; 64 65 /* 66 * The IMMUTABLE and APPEND_ONLY flags can only be changed by 67 * the relevant capability. 68 * 69 * This test looks nicer. Thanks to Pauline Middelink 70 */ 71 if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) { 72 if (!capable(CAP_LINUX_IMMUTABLE)) 73 goto flags_out; 74 } 75 76 /* 77 * The JOURNAL_DATA flag can only be changed by 78 * the relevant capability. 79 */ 80 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) { 81 if (!capable(CAP_SYS_RESOURCE)) 82 goto flags_out; 83 } 84 if (oldflags & EXT4_EXTENTS_FL) { 85 /* We don't support clearning extent flags */ 86 if (!(flags & EXT4_EXTENTS_FL)) { 87 err = -EOPNOTSUPP; 88 goto flags_out; 89 } 90 } else if (flags & EXT4_EXTENTS_FL) { 91 /* migrate the file */ 92 migrate = 1; 93 flags &= ~EXT4_EXTENTS_FL; 94 } 95 96 handle = ext4_journal_start(inode, 1); 97 if (IS_ERR(handle)) { 98 err = PTR_ERR(handle); 99 goto flags_out; 100 } 101 if (IS_SYNC(inode)) 102 handle->h_sync = 1; 103 err = ext4_reserve_inode_write(handle, inode, &iloc); 104 if (err) 105 goto flags_err; 106 107 flags = flags & EXT4_FL_USER_MODIFIABLE; 108 flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE; 109 ei->i_flags = flags; 110 111 ext4_set_inode_flags(inode); 112 inode->i_ctime = ext4_current_time(inode); 113 114 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 115 flags_err: 116 ext4_journal_stop(handle); 117 if (err) 118 goto flags_out; 119 120 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) 121 err = ext4_change_inode_journal_flag(inode, jflag); 122 if (err) 123 goto flags_out; 124 if (migrate) 125 err = ext4_ext_migrate(inode); 126 flags_out: 127 mutex_unlock(&inode->i_mutex); 128 mnt_drop_write(filp->f_path.mnt); 129 return err; 130 } 131 case EXT4_IOC_GETVERSION: 132 case EXT4_IOC_GETVERSION_OLD: 133 return put_user(inode->i_generation, (int __user *) arg); 134 case EXT4_IOC_SETVERSION: 135 case EXT4_IOC_SETVERSION_OLD: { 136 handle_t *handle; 137 struct ext4_iloc iloc; 138 __u32 generation; 139 int err; 140 141 if (!is_owner_or_cap(inode)) 142 return -EPERM; 143 144 err = mnt_want_write(filp->f_path.mnt); 145 if (err) 146 return err; 147 if (get_user(generation, (int __user *) arg)) { 148 err = -EFAULT; 149 goto setversion_out; 150 } 151 152 handle = ext4_journal_start(inode, 1); 153 if (IS_ERR(handle)) { 154 err = PTR_ERR(handle); 155 goto setversion_out; 156 } 157 err = ext4_reserve_inode_write(handle, inode, &iloc); 158 if (err == 0) { 159 inode->i_ctime = ext4_current_time(inode); 160 inode->i_generation = generation; 161 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 162 } 163 ext4_journal_stop(handle); 164 setversion_out: 165 mnt_drop_write(filp->f_path.mnt); 166 return err; 167 } 168 #ifdef CONFIG_JBD2_DEBUG 169 case EXT4_IOC_WAIT_FOR_READONLY: 170 /* 171 * This is racy - by the time we're woken up and running, 172 * the superblock could be released. And the module could 173 * have been unloaded. So sue me. 174 * 175 * Returns 1 if it slept, else zero. 176 */ 177 { 178 struct super_block *sb = inode->i_sb; 179 DECLARE_WAITQUEUE(wait, current); 180 int ret = 0; 181 182 set_current_state(TASK_INTERRUPTIBLE); 183 add_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait); 184 if (timer_pending(&EXT4_SB(sb)->turn_ro_timer)) { 185 schedule(); 186 ret = 1; 187 } 188 remove_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait); 189 return ret; 190 } 191 #endif 192 case EXT4_IOC_GROUP_EXTEND: { 193 ext4_fsblk_t n_blocks_count; 194 struct super_block *sb = inode->i_sb; 195 int err, err2; 196 197 if (!capable(CAP_SYS_RESOURCE)) 198 return -EPERM; 199 200 if (get_user(n_blocks_count, (__u32 __user *)arg)) 201 return -EFAULT; 202 203 err = mnt_want_write(filp->f_path.mnt); 204 if (err) 205 return err; 206 207 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count); 208 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); 209 err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal); 210 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); 211 if (err == 0) 212 err = err2; 213 mnt_drop_write(filp->f_path.mnt); 214 215 return err; 216 } 217 case EXT4_IOC_GROUP_ADD: { 218 struct ext4_new_group_data input; 219 struct super_block *sb = inode->i_sb; 220 int err, err2; 221 222 if (!capable(CAP_SYS_RESOURCE)) 223 return -EPERM; 224 225 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg, 226 sizeof(input))) 227 return -EFAULT; 228 229 err = mnt_want_write(filp->f_path.mnt); 230 if (err) 231 return err; 232 233 err = ext4_group_add(sb, &input); 234 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); 235 err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal); 236 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); 237 if (err == 0) 238 err = err2; 239 mnt_drop_write(filp->f_path.mnt); 240 241 return err; 242 } 243 244 case EXT4_IOC_MIGRATE: 245 { 246 int err; 247 if (!is_owner_or_cap(inode)) 248 return -EACCES; 249 250 err = mnt_want_write(filp->f_path.mnt); 251 if (err) 252 return err; 253 /* 254 * inode_mutex prevent write and truncate on the file. 255 * Read still goes through. We take i_data_sem in 256 * ext4_ext_swap_inode_data before we switch the 257 * inode format to prevent read. 258 */ 259 mutex_lock(&(inode->i_mutex)); 260 err = ext4_ext_migrate(inode); 261 mutex_unlock(&(inode->i_mutex)); 262 mnt_drop_write(filp->f_path.mnt); 263 return err; 264 } 265 266 default: 267 return -ENOTTY; 268 } 269 } 270 271 #ifdef CONFIG_COMPAT 272 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 273 { 274 /* These are just misnamed, they actually get/put from/to user an int */ 275 switch (cmd) { 276 case EXT4_IOC32_GETFLAGS: 277 cmd = EXT4_IOC_GETFLAGS; 278 break; 279 case EXT4_IOC32_SETFLAGS: 280 cmd = EXT4_IOC_SETFLAGS; 281 break; 282 case EXT4_IOC32_GETVERSION: 283 cmd = EXT4_IOC_GETVERSION; 284 break; 285 case EXT4_IOC32_SETVERSION: 286 cmd = EXT4_IOC_SETVERSION; 287 break; 288 case EXT4_IOC32_GROUP_EXTEND: 289 cmd = EXT4_IOC_GROUP_EXTEND; 290 break; 291 case EXT4_IOC32_GETVERSION_OLD: 292 cmd = EXT4_IOC_GETVERSION_OLD; 293 break; 294 case EXT4_IOC32_SETVERSION_OLD: 295 cmd = EXT4_IOC_SETVERSION_OLD; 296 break; 297 #ifdef CONFIG_JBD2_DEBUG 298 case EXT4_IOC32_WAIT_FOR_READONLY: 299 cmd = EXT4_IOC_WAIT_FOR_READONLY; 300 break; 301 #endif 302 case EXT4_IOC32_GETRSVSZ: 303 cmd = EXT4_IOC_GETRSVSZ; 304 break; 305 case EXT4_IOC32_SETRSVSZ: 306 cmd = EXT4_IOC_SETRSVSZ; 307 break; 308 case EXT4_IOC_GROUP_ADD: 309 break; 310 default: 311 return -ENOIOCTLCMD; 312 } 313 return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); 314 } 315 #endif 316