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 /*
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 */
22 int reiserfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
23 unsigned long arg)
24 {
25 unsigned int flags;
26
27 switch (cmd) {
28 case REISERFS_IOC_UNPACK:
29 if (S_ISREG(inode->i_mode)) {
30 if (arg)
31 return reiserfs_unpack(inode, filp);
32 else
33 return 0;
34 } else
35 return -ENOTTY;
36 /* following two cases are taken from fs/ext2/ioctl.c by Remy
37 Card (card@masi.ibp.fr) */
38 case REISERFS_IOC_GETFLAGS:
39 if (!reiserfs_attrs(inode->i_sb))
40 return -ENOTTY;
41
42 flags = REISERFS_I(inode)->i_attrs;
43 i_attrs_to_sd_attrs(inode, (__u16 *) & flags);
44 return put_user(flags, (int __user *)arg);
45 case REISERFS_IOC_SETFLAGS:{
46 if (!reiserfs_attrs(inode->i_sb))
47 return -ENOTTY;
48
49 if (IS_RDONLY(inode))
50 return -EROFS;
51
52 if (!is_owner_or_cap(inode))
53 return -EPERM;
54
55 if (get_user(flags, (int __user *)arg))
56 return -EFAULT;
57
58 /* Is it quota file? Do not allow user to mess with it. */
59 if (IS_NOQUOTA(inode))
60 return -EPERM;
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 (!is_owner_or_cap(inode))
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_path.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 int reiserfs_commit_write(struct file *f, struct page *page,
133 unsigned from, unsigned to);
134 int reiserfs_prepare_write(struct file *f, struct page *page,
135 unsigned from, unsigned to);
136 /*
137 ** reiserfs_unpack
138 ** Function try to convert tail from direct item into indirect.
139 ** It set up nopack attribute in the REISERFS_I(inode)->nopack
140 */
141 int reiserfs_unpack(struct inode *inode, struct file *filp)
142 {
143 int retval = 0;
144 int index;
145 struct page *page;
146 struct address_space *mapping;
147 unsigned long write_from;
148 unsigned long blocksize = inode->i_sb->s_blocksize;
149
150 if (inode->i_size == 0) {
151 REISERFS_I(inode)->i_flags |= i_nopack_mask;
152 return 0;
153 }
154 /* ioctl already done */
155 if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
156 return 0;
157 }
158
159 /* we need to make sure nobody is changing the file size beneath
160 ** us
161 */
162 mutex_lock(&inode->i_mutex);
163 reiserfs_write_lock(inode->i_sb);
164
165 write_from = inode->i_size & (blocksize - 1);
166 /* if we are on a block boundary, we are already unpacked. */
167 if (write_from == 0) {
168 REISERFS_I(inode)->i_flags |= i_nopack_mask;
169 goto out;
170 }
171
172 /* we unpack by finding the page with the tail, and calling
173 ** reiserfs_prepare_write on that page. This will force a
174 ** reiserfs_get_block to unpack the tail for us.
175 */
176 index = inode->i_size >> PAGE_CACHE_SHIFT;
177 mapping = inode->i_mapping;
178 page = grab_cache_page(mapping, index);
179 retval = -ENOMEM;
180 if (!page) {
181 goto out;
182 }
183 retval = reiserfs_prepare_write(NULL, page, write_from, write_from);
184 if (retval)
185 goto out_unlock;
186
187 /* conversion can change page contents, must flush */
188 flush_dcache_page(page);
189 retval = reiserfs_commit_write(NULL, page, write_from, write_from);
190 REISERFS_I(inode)->i_flags |= i_nopack_mask;
191
192 out_unlock:
193 unlock_page(page);
194 page_cache_release(page);
195
196 out:
197 mutex_unlock(&inode->i_mutex);
198 reiserfs_write_unlock(inode->i_sb);
199 return retval;
200 }
201
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