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/capability.h>
13 #include <linux/ext3_fs.h>
14 #include <linux/ext3_jbd.h>
15 #include <linux/mount.h>
16 #include <linux/time.h>
17 #include <linux/compat.h>
18 #include <asm/uaccess.h>
19 
ext3_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)20 long ext3_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
21 {
22 	struct inode *inode = filp->f_dentry->d_inode;
23 	struct ext3_inode_info *ei = EXT3_I(inode);
24 	unsigned int flags;
25 	unsigned short rsv_window_size;
26 
27 	ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg);
28 
29 	switch (cmd) {
30 	case EXT3_IOC_GETFLAGS:
31 		ext3_get_inode_flags(ei);
32 		flags = ei->i_flags & EXT3_FL_USER_VISIBLE;
33 		return put_user(flags, (int __user *) arg);
34 	case EXT3_IOC_SETFLAGS: {
35 		handle_t *handle = NULL;
36 		int err;
37 		struct ext3_iloc iloc;
38 		unsigned int oldflags;
39 		unsigned int jflag;
40 
41 		if (!inode_owner_or_capable(inode))
42 			return -EACCES;
43 
44 		if (get_user(flags, (int __user *) arg))
45 			return -EFAULT;
46 
47 		err = mnt_want_write_file(filp);
48 		if (err)
49 			return err;
50 
51 		flags = ext3_mask_flags(inode->i_mode, flags);
52 
53 		mutex_lock(&inode->i_mutex);
54 
55 		/* Is it quota file? Do not allow user to mess with it */
56 		err = -EPERM;
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 & EXT3_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) & (EXT3_APPEND_FL | EXT3_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) & (EXT3_JOURNAL_DATA_FL)) {
81 			if (!capable(CAP_SYS_RESOURCE))
82 				goto flags_out;
83 		}
84 
85 		handle = ext3_journal_start(inode, 1);
86 		if (IS_ERR(handle)) {
87 			err = PTR_ERR(handle);
88 			goto flags_out;
89 		}
90 		if (IS_SYNC(inode))
91 			handle->h_sync = 1;
92 		err = ext3_reserve_inode_write(handle, inode, &iloc);
93 		if (err)
94 			goto flags_err;
95 
96 		flags = flags & EXT3_FL_USER_MODIFIABLE;
97 		flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
98 		ei->i_flags = flags;
99 
100 		ext3_set_inode_flags(inode);
101 		inode->i_ctime = CURRENT_TIME_SEC;
102 
103 		err = ext3_mark_iloc_dirty(handle, inode, &iloc);
104 flags_err:
105 		ext3_journal_stop(handle);
106 		if (err)
107 			goto flags_out;
108 
109 		if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
110 			err = ext3_change_inode_journal_flag(inode, jflag);
111 flags_out:
112 		mutex_unlock(&inode->i_mutex);
113 		mnt_drop_write_file(filp);
114 		return err;
115 	}
116 	case EXT3_IOC_GETVERSION:
117 	case EXT3_IOC_GETVERSION_OLD:
118 		return put_user(inode->i_generation, (int __user *) arg);
119 	case EXT3_IOC_SETVERSION:
120 	case EXT3_IOC_SETVERSION_OLD: {
121 		handle_t *handle;
122 		struct ext3_iloc iloc;
123 		__u32 generation;
124 		int err;
125 
126 		if (!inode_owner_or_capable(inode))
127 			return -EPERM;
128 
129 		err = mnt_want_write_file(filp);
130 		if (err)
131 			return err;
132 		if (get_user(generation, (int __user *) arg)) {
133 			err = -EFAULT;
134 			goto setversion_out;
135 		}
136 
137 		mutex_lock(&inode->i_mutex);
138 		handle = ext3_journal_start(inode, 1);
139 		if (IS_ERR(handle)) {
140 			err = PTR_ERR(handle);
141 			goto unlock_out;
142 		}
143 		err = ext3_reserve_inode_write(handle, inode, &iloc);
144 		if (err == 0) {
145 			inode->i_ctime = CURRENT_TIME_SEC;
146 			inode->i_generation = generation;
147 			err = ext3_mark_iloc_dirty(handle, inode, &iloc);
148 		}
149 		ext3_journal_stop(handle);
150 
151 unlock_out:
152 		mutex_unlock(&inode->i_mutex);
153 setversion_out:
154 		mnt_drop_write_file(filp);
155 		return err;
156 	}
157 	case EXT3_IOC_GETRSVSZ:
158 		if (test_opt(inode->i_sb, RESERVATION)
159 			&& S_ISREG(inode->i_mode)
160 			&& ei->i_block_alloc_info) {
161 			rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
162 			return put_user(rsv_window_size, (int __user *)arg);
163 		}
164 		return -ENOTTY;
165 	case EXT3_IOC_SETRSVSZ: {
166 		int err;
167 
168 		if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
169 			return -ENOTTY;
170 
171 		err = mnt_want_write_file(filp);
172 		if (err)
173 			return err;
174 
175 		if (!inode_owner_or_capable(inode)) {
176 			err = -EACCES;
177 			goto setrsvsz_out;
178 		}
179 
180 		if (get_user(rsv_window_size, (int __user *)arg)) {
181 			err = -EFAULT;
182 			goto setrsvsz_out;
183 		}
184 
185 		if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
186 			rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
187 
188 		/*
189 		 * need to allocate reservation structure for this inode
190 		 * before set the window size
191 		 */
192 		mutex_lock(&ei->truncate_mutex);
193 		if (!ei->i_block_alloc_info)
194 			ext3_init_block_alloc_info(inode);
195 
196 		if (ei->i_block_alloc_info){
197 			struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
198 			rsv->rsv_goal_size = rsv_window_size;
199 		}
200 		mutex_unlock(&ei->truncate_mutex);
201 setrsvsz_out:
202 		mnt_drop_write_file(filp);
203 		return err;
204 	}
205 	case EXT3_IOC_GROUP_EXTEND: {
206 		ext3_fsblk_t n_blocks_count;
207 		struct super_block *sb = inode->i_sb;
208 		int err, err2;
209 
210 		if (!capable(CAP_SYS_RESOURCE))
211 			return -EPERM;
212 
213 		err = mnt_want_write_file(filp);
214 		if (err)
215 			return err;
216 
217 		if (get_user(n_blocks_count, (__u32 __user *)arg)) {
218 			err = -EFAULT;
219 			goto group_extend_out;
220 		}
221 		err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
222 		journal_lock_updates(EXT3_SB(sb)->s_journal);
223 		err2 = journal_flush(EXT3_SB(sb)->s_journal);
224 		journal_unlock_updates(EXT3_SB(sb)->s_journal);
225 		if (err == 0)
226 			err = err2;
227 group_extend_out:
228 		mnt_drop_write_file(filp);
229 		return err;
230 	}
231 	case EXT3_IOC_GROUP_ADD: {
232 		struct ext3_new_group_data input;
233 		struct super_block *sb = inode->i_sb;
234 		int err, err2;
235 
236 		if (!capable(CAP_SYS_RESOURCE))
237 			return -EPERM;
238 
239 		err = mnt_want_write_file(filp);
240 		if (err)
241 			return err;
242 
243 		if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
244 				sizeof(input))) {
245 			err = -EFAULT;
246 			goto group_add_out;
247 		}
248 
249 		err = ext3_group_add(sb, &input);
250 		journal_lock_updates(EXT3_SB(sb)->s_journal);
251 		err2 = journal_flush(EXT3_SB(sb)->s_journal);
252 		journal_unlock_updates(EXT3_SB(sb)->s_journal);
253 		if (err == 0)
254 			err = err2;
255 group_add_out:
256 		mnt_drop_write_file(filp);
257 		return err;
258 	}
259 	case FITRIM: {
260 
261 		struct super_block *sb = inode->i_sb;
262 		struct fstrim_range range;
263 		int ret = 0;
264 
265 		if (!capable(CAP_SYS_ADMIN))
266 			return -EPERM;
267 
268 		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
269 				   sizeof(range)))
270 			return -EFAULT;
271 
272 		ret = ext3_trim_fs(sb, &range);
273 		if (ret < 0)
274 			return ret;
275 
276 		if (copy_to_user((struct fstrim_range __user *)arg, &range,
277 				 sizeof(range)))
278 			return -EFAULT;
279 
280 		return 0;
281 	}
282 
283 	default:
284 		return -ENOTTY;
285 	}
286 }
287 
288 #ifdef CONFIG_COMPAT
ext3_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)289 long ext3_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
290 {
291 	/* These are just misnamed, they actually get/put from/to user an int */
292 	switch (cmd) {
293 	case EXT3_IOC32_GETFLAGS:
294 		cmd = EXT3_IOC_GETFLAGS;
295 		break;
296 	case EXT3_IOC32_SETFLAGS:
297 		cmd = EXT3_IOC_SETFLAGS;
298 		break;
299 	case EXT3_IOC32_GETVERSION:
300 		cmd = EXT3_IOC_GETVERSION;
301 		break;
302 	case EXT3_IOC32_SETVERSION:
303 		cmd = EXT3_IOC_SETVERSION;
304 		break;
305 	case EXT3_IOC32_GROUP_EXTEND:
306 		cmd = EXT3_IOC_GROUP_EXTEND;
307 		break;
308 	case EXT3_IOC32_GETVERSION_OLD:
309 		cmd = EXT3_IOC_GETVERSION_OLD;
310 		break;
311 	case EXT3_IOC32_SETVERSION_OLD:
312 		cmd = EXT3_IOC_SETVERSION_OLD;
313 		break;
314 #ifdef CONFIG_JBD_DEBUG
315 	case EXT3_IOC32_WAIT_FOR_READONLY:
316 		cmd = EXT3_IOC_WAIT_FOR_READONLY;
317 		break;
318 #endif
319 	case EXT3_IOC32_GETRSVSZ:
320 		cmd = EXT3_IOC_GETRSVSZ;
321 		break;
322 	case EXT3_IOC32_SETRSVSZ:
323 		cmd = EXT3_IOC_SETRSVSZ;
324 		break;
325 	case EXT3_IOC_GROUP_ADD:
326 		break;
327 	default:
328 		return -ENOIOCTLCMD;
329 	}
330 	return ext3_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
331 }
332 #endif
333