Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/ext3/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/jbd.h> |
| 12 | #include <linux/ext3_fs.h> |
| 13 | #include <linux/ext3_jbd.h> |
| 14 | #include <linux/time.h> |
| 15 | #include <asm/uaccess.h> |
| 16 | |
| 17 | |
| 18 | int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, |
| 19 | unsigned long arg) |
| 20 | { |
| 21 | struct ext3_inode_info *ei = EXT3_I(inode); |
| 22 | unsigned int flags; |
| 23 | unsigned short rsv_window_size; |
| 24 | |
| 25 | ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg); |
| 26 | |
| 27 | switch (cmd) { |
| 28 | case EXT3_IOC_GETFLAGS: |
| 29 | flags = ei->i_flags & EXT3_FL_USER_VISIBLE; |
| 30 | return put_user(flags, (int __user *) arg); |
| 31 | case EXT3_IOC_SETFLAGS: { |
| 32 | handle_t *handle = NULL; |
| 33 | int err; |
| 34 | struct ext3_iloc iloc; |
| 35 | unsigned int oldflags; |
| 36 | unsigned int jflag; |
| 37 | |
| 38 | if (IS_RDONLY(inode)) |
| 39 | return -EROFS; |
| 40 | |
| 41 | if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) |
| 42 | return -EACCES; |
| 43 | |
| 44 | if (get_user(flags, (int __user *) arg)) |
| 45 | return -EFAULT; |
| 46 | |
| 47 | if (!S_ISDIR(inode->i_mode)) |
| 48 | flags &= ~EXT3_DIRSYNC_FL; |
| 49 | |
| 50 | oldflags = ei->i_flags; |
| 51 | |
| 52 | /* The JOURNAL_DATA flag is modifiable only by root */ |
| 53 | jflag = flags & EXT3_JOURNAL_DATA_FL; |
| 54 | |
| 55 | /* |
| 56 | * The IMMUTABLE and APPEND_ONLY flags can only be changed by |
| 57 | * the relevant capability. |
| 58 | * |
| 59 | * This test looks nicer. Thanks to Pauline Middelink |
| 60 | */ |
| 61 | if ((flags ^ oldflags) & (EXT3_APPEND_FL | EXT3_IMMUTABLE_FL)) { |
| 62 | if (!capable(CAP_LINUX_IMMUTABLE)) |
| 63 | return -EPERM; |
| 64 | } |
| 65 | |
| 66 | /* |
| 67 | * The JOURNAL_DATA flag can only be changed by |
| 68 | * the relevant capability. |
| 69 | */ |
| 70 | if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) { |
| 71 | if (!capable(CAP_SYS_RESOURCE)) |
| 72 | return -EPERM; |
| 73 | } |
| 74 | |
| 75 | |
| 76 | handle = ext3_journal_start(inode, 1); |
| 77 | if (IS_ERR(handle)) |
| 78 | return PTR_ERR(handle); |
| 79 | if (IS_SYNC(inode)) |
| 80 | handle->h_sync = 1; |
| 81 | err = ext3_reserve_inode_write(handle, inode, &iloc); |
| 82 | if (err) |
| 83 | goto flags_err; |
| 84 | |
| 85 | flags = flags & EXT3_FL_USER_MODIFIABLE; |
| 86 | flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE; |
| 87 | ei->i_flags = flags; |
| 88 | |
| 89 | ext3_set_inode_flags(inode); |
| 90 | inode->i_ctime = CURRENT_TIME_SEC; |
| 91 | |
| 92 | err = ext3_mark_iloc_dirty(handle, inode, &iloc); |
| 93 | flags_err: |
| 94 | ext3_journal_stop(handle); |
| 95 | if (err) |
| 96 | return err; |
| 97 | |
| 98 | if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) |
| 99 | err = ext3_change_inode_journal_flag(inode, jflag); |
| 100 | return err; |
| 101 | } |
| 102 | case EXT3_IOC_GETVERSION: |
| 103 | case EXT3_IOC_GETVERSION_OLD: |
| 104 | return put_user(inode->i_generation, (int __user *) arg); |
| 105 | case EXT3_IOC_SETVERSION: |
| 106 | case EXT3_IOC_SETVERSION_OLD: { |
| 107 | handle_t *handle; |
| 108 | struct ext3_iloc iloc; |
| 109 | __u32 generation; |
| 110 | int err; |
| 111 | |
| 112 | if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) |
| 113 | return -EPERM; |
| 114 | if (IS_RDONLY(inode)) |
| 115 | return -EROFS; |
| 116 | if (get_user(generation, (int __user *) arg)) |
| 117 | return -EFAULT; |
| 118 | |
| 119 | handle = ext3_journal_start(inode, 1); |
| 120 | if (IS_ERR(handle)) |
| 121 | return PTR_ERR(handle); |
| 122 | err = ext3_reserve_inode_write(handle, inode, &iloc); |
| 123 | if (err == 0) { |
| 124 | inode->i_ctime = CURRENT_TIME_SEC; |
| 125 | inode->i_generation = generation; |
| 126 | err = ext3_mark_iloc_dirty(handle, inode, &iloc); |
| 127 | } |
| 128 | ext3_journal_stop(handle); |
| 129 | return err; |
| 130 | } |
| 131 | #ifdef CONFIG_JBD_DEBUG |
| 132 | case EXT3_IOC_WAIT_FOR_READONLY: |
| 133 | /* |
| 134 | * This is racy - by the time we're woken up and running, |
| 135 | * the superblock could be released. And the module could |
| 136 | * have been unloaded. So sue me. |
| 137 | * |
| 138 | * Returns 1 if it slept, else zero. |
| 139 | */ |
| 140 | { |
| 141 | struct super_block *sb = inode->i_sb; |
| 142 | DECLARE_WAITQUEUE(wait, current); |
| 143 | int ret = 0; |
| 144 | |
| 145 | set_current_state(TASK_INTERRUPTIBLE); |
| 146 | add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait); |
| 147 | if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) { |
| 148 | schedule(); |
| 149 | ret = 1; |
| 150 | } |
| 151 | remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait); |
| 152 | return ret; |
| 153 | } |
| 154 | #endif |
| 155 | case EXT3_IOC_GETRSVSZ: |
| 156 | if (test_opt(inode->i_sb, RESERVATION) |
| 157 | && S_ISREG(inode->i_mode) |
| 158 | && ei->i_block_alloc_info) { |
| 159 | rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size; |
| 160 | return put_user(rsv_window_size, (int __user *)arg); |
| 161 | } |
| 162 | return -ENOTTY; |
| 163 | case EXT3_IOC_SETRSVSZ: { |
| 164 | |
| 165 | if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode)) |
| 166 | return -ENOTTY; |
| 167 | |
| 168 | if (IS_RDONLY(inode)) |
| 169 | return -EROFS; |
| 170 | |
| 171 | if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) |
| 172 | return -EACCES; |
| 173 | |
| 174 | if (get_user(rsv_window_size, (int __user *)arg)) |
| 175 | return -EFAULT; |
| 176 | |
| 177 | if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS) |
| 178 | rsv_window_size = EXT3_MAX_RESERVE_BLOCKS; |
| 179 | |
| 180 | /* |
| 181 | * need to allocate reservation structure for this inode |
| 182 | * before set the window size |
| 183 | */ |
| 184 | down(&ei->truncate_sem); |
| 185 | if (!ei->i_block_alloc_info) |
| 186 | ext3_init_block_alloc_info(inode); |
| 187 | |
| 188 | if (ei->i_block_alloc_info){ |
| 189 | struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node; |
| 190 | rsv->rsv_goal_size = rsv_window_size; |
| 191 | } |
| 192 | up(&ei->truncate_sem); |
| 193 | return 0; |
| 194 | } |
| 195 | case EXT3_IOC_GROUP_EXTEND: { |
| 196 | unsigned long n_blocks_count; |
| 197 | struct super_block *sb = inode->i_sb; |
| 198 | int err; |
| 199 | |
| 200 | if (!capable(CAP_SYS_RESOURCE)) |
| 201 | return -EPERM; |
| 202 | |
| 203 | if (IS_RDONLY(inode)) |
| 204 | return -EROFS; |
| 205 | |
| 206 | if (get_user(n_blocks_count, (__u32 __user *)arg)) |
| 207 | return -EFAULT; |
| 208 | |
| 209 | err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count); |
| 210 | journal_lock_updates(EXT3_SB(sb)->s_journal); |
| 211 | journal_flush(EXT3_SB(sb)->s_journal); |
| 212 | journal_unlock_updates(EXT3_SB(sb)->s_journal); |
| 213 | |
| 214 | return err; |
| 215 | } |
| 216 | case EXT3_IOC_GROUP_ADD: { |
| 217 | struct ext3_new_group_data input; |
| 218 | struct super_block *sb = inode->i_sb; |
| 219 | int err; |
| 220 | |
| 221 | if (!capable(CAP_SYS_RESOURCE)) |
| 222 | return -EPERM; |
| 223 | |
| 224 | if (IS_RDONLY(inode)) |
| 225 | return -EROFS; |
| 226 | |
| 227 | if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg, |
| 228 | sizeof(input))) |
| 229 | return -EFAULT; |
| 230 | |
| 231 | err = ext3_group_add(sb, &input); |
| 232 | journal_lock_updates(EXT3_SB(sb)->s_journal); |
| 233 | journal_flush(EXT3_SB(sb)->s_journal); |
| 234 | journal_unlock_updates(EXT3_SB(sb)->s_journal); |
| 235 | |
| 236 | return err; |
| 237 | } |
| 238 | |
| 239 | |
| 240 | default: |
| 241 | return -ENOTTY; |
| 242 | } |
| 243 | } |