1/*
2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3 */
4
5#include <linux/capability.h>
6#include <linux/fs.h>
7#include <linux/mount.h>
8#include "reiserfs.h"
9#include <linux/time.h>
10#include <linux/uaccess.h>
11#include <linux/pagemap.h>
12#include <linux/compat.h>
13
14/*
15 * reiserfs_ioctl - handler for ioctl for inode
16 * supported commands:
17 *  1) REISERFS_IOC_UNPACK - try to unpack tail from direct item into indirect
18 *                           and prevent packing file (argument arg has t
19 *			      be non-zero)
20 *  2) REISERFS_IOC_[GS]ETFLAGS, REISERFS_IOC_[GS]ETVERSION
21 *  3) That's all for a while ...
22 */
23long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
24{
25	struct inode *inode = file_inode(filp);
26	unsigned int flags;
27	int err = 0;
28
29	reiserfs_write_lock(inode->i_sb);
30
31	switch (cmd) {
32	case REISERFS_IOC_UNPACK:
33		if (S_ISREG(inode->i_mode)) {
34			if (arg)
35				err = reiserfs_unpack(inode, filp);
36		} else
37			err = -ENOTTY;
38		break;
39		/*
40		 * following two cases are taken from fs/ext2/ioctl.c by Remy
41		 * Card (card@masi.ibp.fr)
42		 */
43	case REISERFS_IOC_GETFLAGS:
44		if (!reiserfs_attrs(inode->i_sb)) {
45			err = -ENOTTY;
46			break;
47		}
48
49		flags = REISERFS_I(inode)->i_attrs;
50		i_attrs_to_sd_attrs(inode, (__u16 *) & flags);
51		err = put_user(flags, (int __user *)arg);
52		break;
53	case REISERFS_IOC_SETFLAGS:{
54			if (!reiserfs_attrs(inode->i_sb)) {
55				err = -ENOTTY;
56				break;
57			}
58
59			err = mnt_want_write_file(filp);
60			if (err)
61				break;
62
63			if (!inode_owner_or_capable(inode)) {
64				err = -EPERM;
65				goto setflags_out;
66			}
67			if (get_user(flags, (int __user *)arg)) {
68				err = -EFAULT;
69				goto setflags_out;
70			}
71			/*
72			 * Is it quota file? Do not allow user to mess with it
73			 */
74			if (IS_NOQUOTA(inode)) {
75				err = -EPERM;
76				goto setflags_out;
77			}
78			if (((flags ^ REISERFS_I(inode)->
79			      i_attrs) & (REISERFS_IMMUTABLE_FL |
80					  REISERFS_APPEND_FL))
81			    && !capable(CAP_LINUX_IMMUTABLE)) {
82				err = -EPERM;
83				goto setflags_out;
84			}
85			if ((flags & REISERFS_NOTAIL_FL) &&
86			    S_ISREG(inode->i_mode)) {
87				int result;
88
89				result = reiserfs_unpack(inode, filp);
90				if (result) {
91					err = result;
92					goto setflags_out;
93				}
94			}
95			sd_attrs_to_i_attrs(flags, inode);
96			REISERFS_I(inode)->i_attrs = flags;
97			inode->i_ctime = CURRENT_TIME_SEC;
98			mark_inode_dirty(inode);
99setflags_out:
100			mnt_drop_write_file(filp);
101			break;
102		}
103	case REISERFS_IOC_GETVERSION:
104		err = put_user(inode->i_generation, (int __user *)arg);
105		break;
106	case REISERFS_IOC_SETVERSION:
107		if (!inode_owner_or_capable(inode)) {
108			err = -EPERM;
109			break;
110		}
111		err = mnt_want_write_file(filp);
112		if (err)
113			break;
114		if (get_user(inode->i_generation, (int __user *)arg)) {
115			err = -EFAULT;
116			goto setversion_out;
117		}
118		inode->i_ctime = CURRENT_TIME_SEC;
119		mark_inode_dirty(inode);
120setversion_out:
121		mnt_drop_write_file(filp);
122		break;
123	default:
124		err = -ENOTTY;
125	}
126
127	reiserfs_write_unlock(inode->i_sb);
128
129	return err;
130}
131
132#ifdef CONFIG_COMPAT
133long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
134				unsigned long arg)
135{
136	/*
137	 * These are just misnamed, they actually
138	 * get/put from/to user an int
139	 */
140	switch (cmd) {
141	case REISERFS_IOC32_UNPACK:
142		cmd = REISERFS_IOC_UNPACK;
143		break;
144	case REISERFS_IOC32_GETFLAGS:
145		cmd = REISERFS_IOC_GETFLAGS;
146		break;
147	case REISERFS_IOC32_SETFLAGS:
148		cmd = REISERFS_IOC_SETFLAGS;
149		break;
150	case REISERFS_IOC32_GETVERSION:
151		cmd = REISERFS_IOC_GETVERSION;
152		break;
153	case REISERFS_IOC32_SETVERSION:
154		cmd = REISERFS_IOC_SETVERSION;
155		break;
156	default:
157		return -ENOIOCTLCMD;
158	}
159
160	return reiserfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
161}
162#endif
163
164int reiserfs_commit_write(struct file *f, struct page *page,
165			  unsigned from, unsigned to);
166/*
167 * reiserfs_unpack
168 * Function try to convert tail from direct item into indirect.
169 * It set up nopack attribute in the REISERFS_I(inode)->nopack
170 */
171int reiserfs_unpack(struct inode *inode, struct file *filp)
172{
173	int retval = 0;
174	int index;
175	struct page *page;
176	struct address_space *mapping;
177	unsigned long write_from;
178	unsigned long blocksize = inode->i_sb->s_blocksize;
179
180	if (inode->i_size == 0) {
181		REISERFS_I(inode)->i_flags |= i_nopack_mask;
182		return 0;
183	}
184	/* ioctl already done */
185	if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
186		return 0;
187	}
188
189	/* we need to make sure nobody is changing the file size beneath us */
190	reiserfs_mutex_lock_safe(&inode->i_mutex, inode->i_sb);
191
192	reiserfs_write_lock(inode->i_sb);
193
194	write_from = inode->i_size & (blocksize - 1);
195	/* if we are on a block boundary, we are already unpacked.  */
196	if (write_from == 0) {
197		REISERFS_I(inode)->i_flags |= i_nopack_mask;
198		goto out;
199	}
200
201	/*
202	 * we unpack by finding the page with the tail, and calling
203	 * __reiserfs_write_begin on that page.  This will force a
204	 * reiserfs_get_block to unpack the tail for us.
205	 */
206	index = inode->i_size >> PAGE_CACHE_SHIFT;
207	mapping = inode->i_mapping;
208	page = grab_cache_page(mapping, index);
209	retval = -ENOMEM;
210	if (!page) {
211		goto out;
212	}
213	retval = __reiserfs_write_begin(page, write_from, 0);
214	if (retval)
215		goto out_unlock;
216
217	/* conversion can change page contents, must flush */
218	flush_dcache_page(page);
219	retval = reiserfs_commit_write(NULL, page, write_from, write_from);
220	REISERFS_I(inode)->i_flags |= i_nopack_mask;
221
222out_unlock:
223	unlock_page(page);
224	page_cache_release(page);
225
226out:
227	mutex_unlock(&inode->i_mutex);
228	reiserfs_write_unlock(inode->i_sb);
229	return retval;
230}
231