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 <asm/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 to be non-zero)
19 * 2) REISERFS_IOC_[GS]ETFLAGS, REISERFS_IOC_[GS]ETVERSION
20 * 3) That's all for a while ...
21 */
reiserfs_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)22 long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
23 {
24 struct inode *inode = filp->f_path.dentry->d_inode;
25 unsigned int flags;
26 int err = 0;
27
28 reiserfs_write_lock(inode->i_sb);
29
30 switch (cmd) {
31 case REISERFS_IOC_UNPACK:
32 if (S_ISREG(inode->i_mode)) {
33 if (arg)
34 err = reiserfs_unpack(inode, filp);
35 } else
36 err = -ENOTTY;
37 break;
38 /*
39 * following two cases are taken from fs/ext2/ioctl.c by Remy
40 * Card (card@masi.ibp.fr)
41 */
42 case REISERFS_IOC_GETFLAGS:
43 if (!reiserfs_attrs(inode->i_sb)) {
44 err = -ENOTTY;
45 break;
46 }
47
48 flags = REISERFS_I(inode)->i_attrs;
49 i_attrs_to_sd_attrs(inode, (__u16 *) & flags);
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 if (((flags ^ REISERFS_I(inode)->
78 i_attrs) & (REISERFS_IMMUTABLE_FL |
79 REISERFS_APPEND_FL))
80 && !capable(CAP_LINUX_IMMUTABLE)) {
81 err = -EPERM;
82 goto setflags_out;
83 }
84 if ((flags & REISERFS_NOTAIL_FL) &&
85 S_ISREG(inode->i_mode)) {
86 int result;
87
88 result = reiserfs_unpack(inode, filp);
89 if (result) {
90 err = result;
91 goto setflags_out;
92 }
93 }
94 sd_attrs_to_i_attrs(flags, inode);
95 REISERFS_I(inode)->i_attrs = flags;
96 inode->i_ctime = CURRENT_TIME_SEC;
97 mark_inode_dirty(inode);
98 setflags_out:
99 mnt_drop_write_file(filp);
100 break;
101 }
102 case REISERFS_IOC_GETVERSION:
103 err = put_user(inode->i_generation, (int __user *)arg);
104 break;
105 case REISERFS_IOC_SETVERSION:
106 if (!inode_owner_or_capable(inode)) {
107 err = -EPERM;
108 break;
109 }
110 err = mnt_want_write_file(filp);
111 if (err)
112 break;
113 if (get_user(inode->i_generation, (int __user *)arg)) {
114 err = -EFAULT;
115 goto setversion_out;
116 }
117 inode->i_ctime = CURRENT_TIME_SEC;
118 mark_inode_dirty(inode);
119 setversion_out:
120 mnt_drop_write_file(filp);
121 break;
122 default:
123 err = -ENOTTY;
124 }
125
126 reiserfs_write_unlock(inode->i_sb);
127
128 return err;
129 }
130
131 #ifdef CONFIG_COMPAT
reiserfs_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)132 long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
133 unsigned long arg)
134 {
135 /* These are just misnamed, they actually get/put from/to user an int */
136 switch (cmd) {
137 case REISERFS_IOC32_UNPACK:
138 cmd = REISERFS_IOC_UNPACK;
139 break;
140 case REISERFS_IOC32_GETFLAGS:
141 cmd = REISERFS_IOC_GETFLAGS;
142 break;
143 case REISERFS_IOC32_SETFLAGS:
144 cmd = REISERFS_IOC_SETFLAGS;
145 break;
146 case REISERFS_IOC32_GETVERSION:
147 cmd = REISERFS_IOC_GETVERSION;
148 break;
149 case REISERFS_IOC32_SETVERSION:
150 cmd = REISERFS_IOC_SETVERSION;
151 break;
152 default:
153 return -ENOIOCTLCMD;
154 }
155
156 return reiserfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
157 }
158 #endif
159
160 int reiserfs_commit_write(struct file *f, struct page *page,
161 unsigned from, unsigned to);
162 /*
163 ** reiserfs_unpack
164 ** Function try to convert tail from direct item into indirect.
165 ** It set up nopack attribute in the REISERFS_I(inode)->nopack
166 */
reiserfs_unpack(struct inode * inode,struct file * filp)167 int reiserfs_unpack(struct inode *inode, struct file *filp)
168 {
169 int retval = 0;
170 int depth;
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 depth = reiserfs_write_lock_once(inode->i_sb);
187
188 /* we need to make sure nobody is changing the file size beneath us */
189 reiserfs_mutex_lock_safe(&inode->i_mutex, inode->i_sb);
190
191 write_from = inode->i_size & (blocksize - 1);
192 /* if we are on a block boundary, we are already unpacked. */
193 if (write_from == 0) {
194 REISERFS_I(inode)->i_flags |= i_nopack_mask;
195 goto out;
196 }
197
198 /* we unpack by finding the page with the tail, and calling
199 ** __reiserfs_write_begin on that page. This will force a
200 ** reiserfs_get_block to unpack the tail for us.
201 */
202 index = inode->i_size >> PAGE_CACHE_SHIFT;
203 mapping = inode->i_mapping;
204 page = grab_cache_page(mapping, index);
205 retval = -ENOMEM;
206 if (!page) {
207 goto out;
208 }
209 retval = __reiserfs_write_begin(page, write_from, 0);
210 if (retval)
211 goto out_unlock;
212
213 /* conversion can change page contents, must flush */
214 flush_dcache_page(page);
215 retval = reiserfs_commit_write(NULL, page, write_from, write_from);
216 REISERFS_I(inode)->i_flags |= i_nopack_mask;
217
218 out_unlock:
219 unlock_page(page);
220 page_cache_release(page);
221
222 out:
223 mutex_unlock(&inode->i_mutex);
224 reiserfs_write_unlock_once(inode->i_sb, depth);
225 return retval;
226 }
227