[PATCH] BLOCK: Move the ReiserFS device ioctl compat stuff to the ReiserFS driver...
[linux-2.6.git] / fs / reiserfs / ioctl.c
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/reiserfs_fs.h>
8 #include <linux/time.h>
9 #include <asm/uaccess.h>
10 #include <linux/pagemap.h>
11 #include <linux/smp_lock.h>
12 #include <linux/compat.h>
13
14 static int reiserfs_unpack(struct inode *inode, struct file *filp);
15
16 /*
17 ** reiserfs_ioctl - handler for ioctl for inode
18 ** supported commands:
19 **  1) REISERFS_IOC_UNPACK - try to unpack tail from direct item into indirect
20 **                           and prevent packing file (argument arg has to be non-zero)
21 **  2) REISERFS_IOC_[GS]ETFLAGS, REISERFS_IOC_[GS]ETVERSION
22 **  3) That's all for a while ...
23 */
24 int reiserfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
25                    unsigned long arg)
26 {
27         unsigned int flags;
28
29         switch (cmd) {
30         case REISERFS_IOC_UNPACK:
31                 if (S_ISREG(inode->i_mode)) {
32                         if (arg)
33                                 return reiserfs_unpack(inode, filp);
34                         else
35                                 return 0;
36                 } else
37                         return -ENOTTY;
38                 /* following two cases are taken from fs/ext2/ioctl.c by Remy
39                    Card (card@masi.ibp.fr) */
40         case REISERFS_IOC_GETFLAGS:
41                 if (!reiserfs_attrs(inode->i_sb))
42                         return -ENOTTY;
43
44                 flags = REISERFS_I(inode)->i_attrs;
45                 i_attrs_to_sd_attrs(inode, (__u16 *) & flags);
46                 return put_user(flags, (int __user *)arg);
47         case REISERFS_IOC_SETFLAGS:{
48                         if (!reiserfs_attrs(inode->i_sb))
49                                 return -ENOTTY;
50
51                         if (IS_RDONLY(inode))
52                                 return -EROFS;
53
54                         if ((current->fsuid != inode->i_uid)
55                             && !capable(CAP_FOWNER))
56                                 return -EPERM;
57
58                         if (get_user(flags, (int __user *)arg))
59                                 return -EFAULT;
60
61                         if (((flags ^ REISERFS_I(inode)->
62                               i_attrs) & (REISERFS_IMMUTABLE_FL |
63                                           REISERFS_APPEND_FL))
64                             && !capable(CAP_LINUX_IMMUTABLE))
65                                 return -EPERM;
66
67                         if ((flags & REISERFS_NOTAIL_FL) &&
68                             S_ISREG(inode->i_mode)) {
69                                 int result;
70
71                                 result = reiserfs_unpack(inode, filp);
72                                 if (result)
73                                         return result;
74                         }
75                         sd_attrs_to_i_attrs(flags, inode);
76                         REISERFS_I(inode)->i_attrs = flags;
77                         inode->i_ctime = CURRENT_TIME_SEC;
78                         mark_inode_dirty(inode);
79                         return 0;
80                 }
81         case REISERFS_IOC_GETVERSION:
82                 return put_user(inode->i_generation, (int __user *)arg);
83         case REISERFS_IOC_SETVERSION:
84                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
85                         return -EPERM;
86                 if (IS_RDONLY(inode))
87                         return -EROFS;
88                 if (get_user(inode->i_generation, (int __user *)arg))
89                         return -EFAULT;
90                 inode->i_ctime = CURRENT_TIME_SEC;
91                 mark_inode_dirty(inode);
92                 return 0;
93         default:
94                 return -ENOTTY;
95         }
96 }
97
98 #ifdef CONFIG_COMPAT
99 long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
100                                 unsigned long arg)
101 {
102         struct inode *inode = file->f_dentry->d_inode;
103         int ret;
104
105         /* These are just misnamed, they actually get/put from/to user an int */
106         switch (cmd) {
107         case REISERFS_IOC32_UNPACK:
108                 cmd = REISERFS_IOC_UNPACK;
109                 break;
110         case REISERFS_IOC32_GETFLAGS:
111                 cmd = REISERFS_IOC_GETFLAGS;
112                 break;
113         case REISERFS_IOC32_SETFLAGS:
114                 cmd = REISERFS_IOC_SETFLAGS;
115                 break;
116         case REISERFS_IOC32_GETVERSION:
117                 cmd = REISERFS_IOC_GETVERSION;
118                 break;
119         case REISERFS_IOC32_SETVERSION:
120                 cmd = REISERFS_IOC_SETVERSION;
121                 break;
122         default:
123                 return -ENOIOCTLCMD;
124         }
125         lock_kernel();
126         ret = reiserfs_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
127         unlock_kernel();
128         return ret;
129 }
130 #endif
131
132 /*
133 ** reiserfs_unpack
134 ** Function try to convert tail from direct item into indirect.
135 ** It set up nopack attribute in the REISERFS_I(inode)->nopack
136 */
137 static int reiserfs_unpack(struct inode *inode, struct file *filp)
138 {
139         int retval = 0;
140         int index;
141         struct page *page;
142         struct address_space *mapping;
143         unsigned long write_from;
144         unsigned long blocksize = inode->i_sb->s_blocksize;
145
146         if (inode->i_size == 0) {
147                 REISERFS_I(inode)->i_flags |= i_nopack_mask;
148                 return 0;
149         }
150         /* ioctl already done */
151         if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
152                 return 0;
153         }
154
155         /* we need to make sure nobody is changing the file size beneath
156          ** us
157          */
158         mutex_lock(&inode->i_mutex);
159         reiserfs_write_lock(inode->i_sb);
160
161         write_from = inode->i_size & (blocksize - 1);
162         /* if we are on a block boundary, we are already unpacked.  */
163         if (write_from == 0) {
164                 REISERFS_I(inode)->i_flags |= i_nopack_mask;
165                 goto out;
166         }
167
168         /* we unpack by finding the page with the tail, and calling
169          ** reiserfs_prepare_write on that page.  This will force a 
170          ** reiserfs_get_block to unpack the tail for us.
171          */
172         index = inode->i_size >> PAGE_CACHE_SHIFT;
173         mapping = inode->i_mapping;
174         page = grab_cache_page(mapping, index);
175         retval = -ENOMEM;
176         if (!page) {
177                 goto out;
178         }
179         retval =
180             mapping->a_ops->prepare_write(NULL, page, write_from, write_from);
181         if (retval)
182                 goto out_unlock;
183
184         /* conversion can change page contents, must flush */
185         flush_dcache_page(page);
186         retval =
187             mapping->a_ops->commit_write(NULL, page, write_from, write_from);
188         REISERFS_I(inode)->i_flags |= i_nopack_mask;
189
190       out_unlock:
191         unlock_page(page);
192         page_cache_release(page);
193
194       out:
195         mutex_unlock(&inode->i_mutex);
196         reiserfs_write_unlock(inode->i_sb);
197         return retval;
198 }