nfs/lsm: make NFSv4 set LSM mount options
[linux-2.6] / 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/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 */
23 int reiserfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
24                    unsigned long arg)
25 {
26         unsigned int flags;
27         int err = 0;
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                         err = mnt_want_write(filp->f_path.mnt);
52                         if (err)
53                                 return err;
54
55                         if (!is_owner_or_cap(inode)) {
56                                 err = -EPERM;
57                                 goto setflags_out;
58                         }
59                         if (get_user(flags, (int __user *)arg)) {
60                                 err = -EFAULT;
61                                 goto setflags_out;
62                         }
63                         /*
64                          * Is it quota file? Do not allow user to mess with it
65                          */
66                         if (IS_NOQUOTA(inode)) {
67                                 err = -EPERM;
68                                 goto setflags_out;
69                         }
70                         if (((flags ^ REISERFS_I(inode)->
71                               i_attrs) & (REISERFS_IMMUTABLE_FL |
72                                           REISERFS_APPEND_FL))
73                             && !capable(CAP_LINUX_IMMUTABLE)) {
74                                 err = -EPERM;
75                                 goto setflags_out;
76                         }
77                         if ((flags & REISERFS_NOTAIL_FL) &&
78                             S_ISREG(inode->i_mode)) {
79                                 int result;
80
81                                 result = reiserfs_unpack(inode, filp);
82                                 if (result) {
83                                         err = result;
84                                         goto setflags_out;
85                                 }
86                         }
87                         sd_attrs_to_i_attrs(flags, inode);
88                         REISERFS_I(inode)->i_attrs = flags;
89                         inode->i_ctime = CURRENT_TIME_SEC;
90                         mark_inode_dirty(inode);
91 setflags_out:
92                         mnt_drop_write(filp->f_path.mnt);
93                         return err;
94                 }
95         case REISERFS_IOC_GETVERSION:
96                 return put_user(inode->i_generation, (int __user *)arg);
97         case REISERFS_IOC_SETVERSION:
98                 if (!is_owner_or_cap(inode))
99                         return -EPERM;
100                 err = mnt_want_write(filp->f_path.mnt);
101                 if (err)
102                         return err;
103                 if (get_user(inode->i_generation, (int __user *)arg)) {
104                         err = -EFAULT;
105                         goto setversion_out;
106                 }
107                 inode->i_ctime = CURRENT_TIME_SEC;
108                 mark_inode_dirty(inode);
109 setversion_out:
110                 mnt_drop_write(filp->f_path.mnt);
111                 return err;
112         default:
113                 return -ENOTTY;
114         }
115 }
116
117 #ifdef CONFIG_COMPAT
118 long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
119                                 unsigned long arg)
120 {
121         struct inode *inode = file->f_path.dentry->d_inode;
122         int ret;
123
124         /* These are just misnamed, they actually get/put from/to user an int */
125         switch (cmd) {
126         case REISERFS_IOC32_UNPACK:
127                 cmd = REISERFS_IOC_UNPACK;
128                 break;
129         case REISERFS_IOC32_GETFLAGS:
130                 cmd = REISERFS_IOC_GETFLAGS;
131                 break;
132         case REISERFS_IOC32_SETFLAGS:
133                 cmd = REISERFS_IOC_SETFLAGS;
134                 break;
135         case REISERFS_IOC32_GETVERSION:
136                 cmd = REISERFS_IOC_GETVERSION;
137                 break;
138         case REISERFS_IOC32_SETVERSION:
139                 cmd = REISERFS_IOC_SETVERSION;
140                 break;
141         default:
142                 return -ENOIOCTLCMD;
143         }
144         lock_kernel();
145         ret = reiserfs_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
146         unlock_kernel();
147         return ret;
148 }
149 #endif
150
151 int reiserfs_commit_write(struct file *f, struct page *page,
152                           unsigned from, unsigned to);
153 int reiserfs_prepare_write(struct file *f, struct page *page,
154                            unsigned from, unsigned to);
155 /*
156 ** reiserfs_unpack
157 ** Function try to convert tail from direct item into indirect.
158 ** It set up nopack attribute in the REISERFS_I(inode)->nopack
159 */
160 int reiserfs_unpack(struct inode *inode, struct file *filp)
161 {
162         int retval = 0;
163         int index;
164         struct page *page;
165         struct address_space *mapping;
166         unsigned long write_from;
167         unsigned long blocksize = inode->i_sb->s_blocksize;
168
169         if (inode->i_size == 0) {
170                 REISERFS_I(inode)->i_flags |= i_nopack_mask;
171                 return 0;
172         }
173         /* ioctl already done */
174         if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
175                 return 0;
176         }
177
178         /* we need to make sure nobody is changing the file size beneath
179          ** us
180          */
181         mutex_lock(&inode->i_mutex);
182         reiserfs_write_lock(inode->i_sb);
183
184         write_from = inode->i_size & (blocksize - 1);
185         /* if we are on a block boundary, we are already unpacked.  */
186         if (write_from == 0) {
187                 REISERFS_I(inode)->i_flags |= i_nopack_mask;
188                 goto out;
189         }
190
191         /* we unpack by finding the page with the tail, and calling
192          ** reiserfs_prepare_write on that page.  This will force a 
193          ** reiserfs_get_block to unpack the tail for us.
194          */
195         index = inode->i_size >> PAGE_CACHE_SHIFT;
196         mapping = inode->i_mapping;
197         page = grab_cache_page(mapping, index);
198         retval = -ENOMEM;
199         if (!page) {
200                 goto out;
201         }
202         retval = reiserfs_prepare_write(NULL, page, write_from, write_from);
203         if (retval)
204                 goto out_unlock;
205
206         /* conversion can change page contents, must flush */
207         flush_dcache_page(page);
208         retval = reiserfs_commit_write(NULL, page, write_from, write_from);
209         REISERFS_I(inode)->i_flags |= i_nopack_mask;
210
211       out_unlock:
212         unlock_page(page);
213         page_cache_release(page);
214
215       out:
216         mutex_unlock(&inode->i_mutex);
217         reiserfs_write_unlock(inode->i_sb);
218         return retval;
219 }