Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
[linux-3.10.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/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 long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
24 {
25         struct inode *inode = filp->f_path.dentry->d_inode;
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                 i_attrs_to_sd_attrs(inode, (__u16 *) & flags);
51                 err = put_user(flags, (int __user *)arg);
52                 break;
53         case REISERFS_IOC_SETFLAGS:{
54                         if (!reiserfs_attrs(inode->i_sb)) {
55                                 err = -ENOTTY;
56                                 break;
57                         }
58
59                         err = mnt_want_write(filp->f_path.mnt);
60                         if (err)
61                                 break;
62
63                         if (!is_owner_or_cap(inode)) {
64                                 err = -EPERM;
65                                 goto setflags_out;
66                         }
67                         if (get_user(flags, (int __user *)arg)) {
68                                 err = -EFAULT;
69                                 goto setflags_out;
70                         }
71                         /*
72                          * Is it quota file? Do not allow user to mess with it
73                          */
74                         if (IS_NOQUOTA(inode)) {
75                                 err = -EPERM;
76                                 goto setflags_out;
77                         }
78                         if (((flags ^ REISERFS_I(inode)->
79                               i_attrs) & (REISERFS_IMMUTABLE_FL |
80                                           REISERFS_APPEND_FL))
81                             && !capable(CAP_LINUX_IMMUTABLE)) {
82                                 err = -EPERM;
83                                 goto setflags_out;
84                         }
85                         if ((flags & REISERFS_NOTAIL_FL) &&
86                             S_ISREG(inode->i_mode)) {
87                                 int result;
88
89                                 result = reiserfs_unpack(inode, filp);
90                                 if (result) {
91                                         err = result;
92                                         goto setflags_out;
93                                 }
94                         }
95                         sd_attrs_to_i_attrs(flags, inode);
96                         REISERFS_I(inode)->i_attrs = flags;
97                         inode->i_ctime = CURRENT_TIME_SEC;
98                         mark_inode_dirty(inode);
99 setflags_out:
100                         mnt_drop_write(filp->f_path.mnt);
101                         break;
102                 }
103         case REISERFS_IOC_GETVERSION:
104                 err = put_user(inode->i_generation, (int __user *)arg);
105                 break;
106         case REISERFS_IOC_SETVERSION:
107                 if (!is_owner_or_cap(inode)) {
108                         err = -EPERM;
109                         break;
110                 }
111                 err = mnt_want_write(filp->f_path.mnt);
112                 if (err)
113                         break;
114                 if (get_user(inode->i_generation, (int __user *)arg)) {
115                         err = -EFAULT;
116                         goto setversion_out;
117                 }
118                 inode->i_ctime = CURRENT_TIME_SEC;
119                 mark_inode_dirty(inode);
120 setversion_out:
121                 mnt_drop_write(filp->f_path.mnt);
122                 break;
123         default:
124                 err = -ENOTTY;
125         }
126
127         reiserfs_write_unlock(inode->i_sb);
128
129         return err;
130 }
131
132 #ifdef CONFIG_COMPAT
133 long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
134                                 unsigned long arg)
135 {
136         /* These are just misnamed, they actually get/put from/to user an int */
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 int reiserfs_prepare_write(struct file *f, struct page *page,
164                            unsigned from, unsigned to);
165 /*
166 ** reiserfs_unpack
167 ** Function try to convert tail from direct item into indirect.
168 ** It set up nopack attribute in the REISERFS_I(inode)->nopack
169 */
170 int reiserfs_unpack(struct inode *inode, struct file *filp)
171 {
172         int retval = 0;
173         int index;
174         struct page *page;
175         struct address_space *mapping;
176         unsigned long write_from;
177         unsigned long blocksize = inode->i_sb->s_blocksize;
178
179         if (inode->i_size == 0) {
180                 REISERFS_I(inode)->i_flags |= i_nopack_mask;
181                 return 0;
182         }
183         /* ioctl already done */
184         if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
185                 return 0;
186         }
187
188         /* we need to make sure nobody is changing the file size beneath
189          ** us
190          */
191         mutex_lock(&inode->i_mutex);
192         reiserfs_write_lock(inode->i_sb);
193
194         write_from = inode->i_size & (blocksize - 1);
195         /* if we are on a block boundary, we are already unpacked.  */
196         if (write_from == 0) {
197                 REISERFS_I(inode)->i_flags |= i_nopack_mask;
198                 goto out;
199         }
200
201         /* we unpack by finding the page with the tail, and calling
202          ** reiserfs_prepare_write on that page.  This will force a
203          ** reiserfs_get_block to unpack the tail for us.
204          */
205         index = inode->i_size >> PAGE_CACHE_SHIFT;
206         mapping = inode->i_mapping;
207         page = grab_cache_page(mapping, index);
208         retval = -ENOMEM;
209         if (!page) {
210                 goto out;
211         }
212         retval = reiserfs_prepare_write(NULL, page, write_from, write_from);
213         if (retval)
214                 goto out_unlock;
215
216         /* conversion can change page contents, must flush */
217         flush_dcache_page(page);
218         retval = reiserfs_commit_write(NULL, page, write_from, write_from);
219         REISERFS_I(inode)->i_flags |= i_nopack_mask;
220
221       out_unlock:
222         unlock_page(page);
223         page_cache_release(page);
224
225       out:
226         mutex_unlock(&inode->i_mutex);
227         reiserfs_write_unlock(inode->i_sb);
228         return retval;
229 }