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 */
reiserfs_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)23 long 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 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 err = vfs_ioc_setflags_prepare(inode,
78 REISERFS_I(inode)->i_attrs,
79 flags);
80 if (err)
81 goto setflags_out;
82 if ((flags & REISERFS_NOTAIL_FL) &&
83 S_ISREG(inode->i_mode)) {
84 int result;
85
86 result = reiserfs_unpack(inode, filp);
87 if (result) {
88 err = result;
89 goto setflags_out;
90 }
91 }
92 sd_attrs_to_i_attrs(flags, inode);
93 REISERFS_I(inode)->i_attrs = flags;
94 inode->i_ctime = current_time(inode);
95 mark_inode_dirty(inode);
96 setflags_out:
97 mnt_drop_write_file(filp);
98 break;
99 }
100 case REISERFS_IOC_GETVERSION:
101 err = put_user(inode->i_generation, (int __user *)arg);
102 break;
103 case REISERFS_IOC_SETVERSION:
104 if (!inode_owner_or_capable(inode)) {
105 err = -EPERM;
106 break;
107 }
108 err = mnt_want_write_file(filp);
109 if (err)
110 break;
111 if (get_user(inode->i_generation, (int __user *)arg)) {
112 err = -EFAULT;
113 goto setversion_out;
114 }
115 inode->i_ctime = current_time(inode);
116 mark_inode_dirty(inode);
117 setversion_out:
118 mnt_drop_write_file(filp);
119 break;
120 default:
121 err = -ENOTTY;
122 }
123
124 reiserfs_write_unlock(inode->i_sb);
125
126 return err;
127 }
128
129 #ifdef CONFIG_COMPAT
reiserfs_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)130 long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
131 unsigned long arg)
132 {
133 /*
134 * These are just misnamed, they actually
135 * get/put from/to user an int
136 */
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
161 int reiserfs_commit_write(struct file *f, struct page *page,
162 unsigned from, unsigned to);
163 /*
164 * reiserfs_unpack
165 * Function try to convert tail from direct item into indirect.
166 * It set up nopack attribute in the REISERFS_I(inode)->nopack
167 */
reiserfs_unpack(struct inode * inode,struct file * filp)168 int reiserfs_unpack(struct inode *inode, struct file *filp)
169 {
170 int retval = 0;
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 /* we need to make sure nobody is changing the file size beneath us */
187 {
188 int depth = reiserfs_write_unlock_nested(inode->i_sb);
189 inode_lock(inode);
190 reiserfs_write_lock_nested(inode->i_sb, depth);
191 }
192
193 reiserfs_write_lock(inode->i_sb);
194
195 write_from = inode->i_size & (blocksize - 1);
196 /* if we are on a block boundary, we are already unpacked. */
197 if (write_from == 0) {
198 REISERFS_I(inode)->i_flags |= i_nopack_mask;
199 goto out;
200 }
201
202 /*
203 * we unpack by finding the page with the tail, and calling
204 * __reiserfs_write_begin on that page. This will force a
205 * reiserfs_get_block to unpack the tail for us.
206 */
207 index = inode->i_size >> PAGE_SHIFT;
208 mapping = inode->i_mapping;
209 page = grab_cache_page(mapping, index);
210 retval = -ENOMEM;
211 if (!page) {
212 goto out;
213 }
214 retval = __reiserfs_write_begin(page, write_from, 0);
215 if (retval)
216 goto out_unlock;
217
218 /* conversion can change page contents, must flush */
219 flush_dcache_page(page);
220 retval = reiserfs_commit_write(NULL, page, write_from, write_from);
221 REISERFS_I(inode)->i_flags |= i_nopack_mask;
222
223 out_unlock:
224 unlock_page(page);
225 put_page(page);
226
227 out:
228 inode_unlock(inode);
229 reiserfs_write_unlock(inode->i_sb);
230 return retval;
231 }
232