Linux Audio

Check our new training course

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