summaryrefslogtreecommitdiff
path: root/fs/reiserfs/ioctl.c
blob: 5e40b0cd4c3d703f57fc96061f305d6e84491a7c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
/*
 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
 */

#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/reiserfs_fs.h>
#include <linux/time.h>
#include <asm/uaccess.h>
#include <linux/pagemap.h>
#include <linux/smp_lock.h>
#include <linux/compat.h>

/*
** reiserfs_ioctl - handler for ioctl for inode
** supported commands:
**  1) REISERFS_IOC_UNPACK - try to unpack tail from direct item into indirect
**                           and prevent packing file (argument arg has to be non-zero)
**  2) REISERFS_IOC_[GS]ETFLAGS, REISERFS_IOC_[GS]ETVERSION
**  3) That's all for a while ...
*/
int reiserfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
		   unsigned long arg)
{
	unsigned int flags;
	int err = 0;

	switch (cmd) {
	case REISERFS_IOC_UNPACK:
		if (S_ISREG(inode->i_mode)) {
			if (arg)
				return reiserfs_unpack(inode, filp);
			else
				return 0;
		} else
			return -ENOTTY;
		/* following two cases are taken from fs/ext2/ioctl.c by Remy
		   Card (card@masi.ibp.fr) */
	case REISERFS_IOC_GETFLAGS:
		if (!reiserfs_attrs(inode->i_sb))
			return -ENOTTY;

		flags = REISERFS_I(inode)->i_attrs;
		i_attrs_to_sd_attrs(inode, (__u16 *) & flags);
		return put_user(flags, (int __user *)arg);
	case REISERFS_IOC_SETFLAGS:{
			if (!reiserfs_attrs(inode->i_sb))
				return -ENOTTY;

			err = mnt_want_write(filp->f_path.mnt);
			if (err)
				return err;

			if (!is_owner_or_cap(inode)) {
				err = -EPERM;
				goto setflags_out;
			}
			if (get_user(flags, (int __user *)arg)) {
				err = -EFAULT;
				goto setflags_out;
			}
			/*
			 * Is it quota file? Do not allow user to mess with it
			 */
			if (IS_NOQUOTA(inode)) {
				err = -EPERM;
				goto setflags_out;
			}
			if (((flags ^ REISERFS_I(inode)->
			      i_attrs) & (REISERFS_IMMUTABLE_FL |
					  REISERFS_APPEND_FL))
			    && !capable(CAP_LINUX_IMMUTABLE)) {
				err = -EPERM;
				goto setflags_out;
			}
			if ((flags & REISERFS_NOTAIL_FL) &&
			    S_ISREG(inode->i_mode)) {
				int result;

				result = reiserfs_unpack(inode, filp);
				if (result) {
					err = result;
					goto setflags_out;
				}
			}
			sd_attrs_to_i_attrs(flags, inode);
			REISERFS_I(inode)->i_attrs = flags;
			inode->i_ctime = CURRENT_TIME_SEC;
			mark_inode_dirty(inode);
setflags_out:
			mnt_drop_write(filp->f_path.mnt);
			return err;
		}
	case REISERFS_IOC_GETVERSION:
		return put_user(inode->i_generation, (int __user *)arg);
	case REISERFS_IOC_SETVERSION:
		if (!is_owner_or_cap(inode))
			return -EPERM;
		err = mnt_want_write(filp->f_path.mnt);
		if (err)
			return err;
		if (get_user(inode->i_generation, (int __user *)arg)) {
			err = -EFAULT;
			goto setversion_out;
		}
		inode->i_ctime = CURRENT_TIME_SEC;
		mark_inode_dirty(inode);
setversion_out:
		mnt_drop_write(filp->f_path.mnt);
		return err;
	default:
		return -ENOTTY;
	}
}

#ifdef CONFIG_COMPAT
long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
				unsigned long arg)
{
	struct inode *inode = file->f_path.dentry->d_inode;
	int ret;

	/* These are just misnamed, they actually get/put from/to user an int */
	switch (cmd) {
	case REISERFS_IOC32_UNPACK:
		cmd = REISERFS_IOC_UNPACK;
		break;
	case REISERFS_IOC32_GETFLAGS:
		cmd = REISERFS_IOC_GETFLAGS;
		break;
	case REISERFS_IOC32_SETFLAGS:
		cmd = REISERFS_IOC_SETFLAGS;
		break;
	case REISERFS_IOC32_GETVERSION:
		cmd = REISERFS_IOC_GETVERSION;
		break;
	case REISERFS_IOC32_SETVERSION:
		cmd = REISERFS_IOC_SETVERSION;
		break;
	default:
		return -ENOIOCTLCMD;
	}

	reiserfs_write_lock(inode->i_sb);
	ret = reiserfs_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
	reiserfs_write_unlock(inode->i_sb);

	return ret;
}
#endif

int reiserfs_commit_write(struct file *f, struct page *page,
			  unsigned from, unsigned to);
int reiserfs_prepare_write(struct file *f, struct page *page,
			   unsigned from, unsigned to);
/*
** reiserfs_unpack
** Function try to convert tail from direct item into indirect.
** It set up nopack attribute in the REISERFS_I(inode)->nopack
*/
int reiserfs_unpack(struct inode *inode, struct file *filp)
{
	int retval = 0;
	int index;
	struct page *page;
	struct address_space *mapping;
	unsigned long write_from;
	unsigned long blocksize = inode->i_sb->s_blocksize;

	if (inode->i_size == 0) {
		REISERFS_I(inode)->i_flags |= i_nopack_mask;
		return 0;
	}
	/* ioctl already done */
	if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
		return 0;
	}

	/* we need to make sure nobody is changing the file size beneath
	 ** us
	 */
	mutex_lock(&inode->i_mutex);
	reiserfs_write_lock(inode->i_sb);

	write_from = inode->i_size & (blocksize - 1);
	/* if we are on a block boundary, we are already unpacked.  */
	if (write_from == 0) {
		REISERFS_I(inode)->i_flags |= i_nopack_mask;
		goto out;
	}

	/* we unpack by finding the page with the tail, and calling
	 ** reiserfs_prepare_write on that page.  This will force a
	 ** reiserfs_get_block to unpack the tail for us.
	 */
	index = inode->i_size >> PAGE_CACHE_SHIFT;
	mapping = inode->i_mapping;
	page = grab_cache_page(mapping, index);
	retval = -ENOMEM;
	if (!page) {
		goto out;
	}
	retval = reiserfs_prepare_write(NULL, page, write_from, write_from);
	if (retval)
		goto out_unlock;

	/* conversion can change page contents, must flush */
	flush_dcache_page(page);
	retval = reiserfs_commit_write(NULL, page, write_from, write_from);
	REISERFS_I(inode)->i_flags |= i_nopack_mask;

      out_unlock:
	unlock_page(page);
	page_cache_release(page);

      out:
	mutex_unlock(&inode->i_mutex);
	reiserfs_write_unlock(inode->i_sb);
	return retval;
}