• Home
  • History
  • Annotate
  • Line#
  • Navigate
  • Raw
  • Download
  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/fs/reiserfs/
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 <linux/reiserfs_fs.h>
9#include <linux/time.h>
10#include <asm/uaccess.h>
11#include <linux/pagemap.h>
12#include <linux/smp_lock.h>
13#include <linux/compat.h>
14
15/*
16 * reiserfs_ioctl - handler for ioctl for inode
17 * supported commands:
18 *  1) REISERFS_IOC_UNPACK - try to unpack tail from direct item into indirect
19 *                           and prevent packing file (argument arg has to 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 = filp->f_path.dentry->d_inode;
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(filp->f_path.mnt);
60			if (err)
61				break;
62
63			if (!is_owner_or_cap(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(filp->f_path.mnt);
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 (!is_owner_or_cap(inode)) {
108			err = -EPERM;
109			break;
110		}
111		err = mnt_want_write(filp->f_path.mnt);
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(filp->f_path.mnt);
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	/* These are just misnamed, they actually get/put from/to user an int */
137	switch (cmd) {
138	case REISERFS_IOC32_UNPACK:
139		cmd = REISERFS_IOC_UNPACK;
140		break;
141	case REISERFS_IOC32_GETFLAGS:
142		cmd = REISERFS_IOC_GETFLAGS;
143		break;
144	case REISERFS_IOC32_SETFLAGS:
145		cmd = REISERFS_IOC_SETFLAGS;
146		break;
147	case REISERFS_IOC32_GETVERSION:
148		cmd = REISERFS_IOC_GETVERSION;
149		break;
150	case REISERFS_IOC32_SETVERSION:
151		cmd = REISERFS_IOC_SETVERSION;
152		break;
153	default:
154		return -ENOIOCTLCMD;
155	}
156
157	return reiserfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
158}
159#endif
160
161int reiserfs_commit_write(struct file *f, struct page *page,
162			  unsigned from, unsigned to);
163int reiserfs_prepare_write(struct file *f, struct page *page,
164			   unsigned from, unsigned to);
165/*
166** reiserfs_unpack
167** Function try to convert tail from direct item into indirect.
168** It set up nopack attribute in the REISERFS_I(inode)->nopack
169*/
170int reiserfs_unpack(struct inode *inode, struct file *filp)
171{
172	int retval = 0;
173	int depth;
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	depth = reiserfs_write_lock_once(inode->i_sb);
190
191	/* we need to make sure nobody is changing the file size beneath us */
192	reiserfs_mutex_lock_safe(&inode->i_mutex, 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	/* we unpack by finding the page with the tail, and calling
202	 ** reiserfs_prepare_write on that page.  This will force a
203	 ** reiserfs_get_block to unpack the tail for us.
204	 */
205	index = inode->i_size >> PAGE_CACHE_SHIFT;
206	mapping = inode->i_mapping;
207	page = grab_cache_page(mapping, index);
208	retval = -ENOMEM;
209	if (!page) {
210		goto out;
211	}
212	retval = reiserfs_prepare_write(NULL, page, write_from, write_from);
213	if (retval)
214		goto out_unlock;
215
216	/* conversion can change page contents, must flush */
217	flush_dcache_page(page);
218	retval = reiserfs_commit_write(NULL, page, write_from, write_from);
219	REISERFS_I(inode)->i_flags |= i_nopack_mask;
220
221      out_unlock:
222	unlock_page(page);
223	page_cache_release(page);
224
225      out:
226	mutex_unlock(&inode->i_mutex);
227	reiserfs_write_unlock_once(inode->i_sb, depth);
228	return retval;
229}
230