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