xref: /openbmc/linux/fs/bad_inode.c (revision 4800cd83)
1 /*
2  *  linux/fs/bad_inode.c
3  *
4  *  Copyright (C) 1997, Stephen Tweedie
5  *
6  *  Provide stub functions for unreadable inodes
7  *
8  *  Fabian Frederick : August 2003 - All file operations assigned to EIO
9  */
10 
11 #include <linux/fs.h>
12 #include <linux/module.h>
13 #include <linux/stat.h>
14 #include <linux/time.h>
15 #include <linux/namei.h>
16 #include <linux/poll.h>
17 
18 
19 static loff_t bad_file_llseek(struct file *file, loff_t offset, int origin)
20 {
21 	return -EIO;
22 }
23 
24 static ssize_t bad_file_read(struct file *filp, char __user *buf,
25 			size_t size, loff_t *ppos)
26 {
27         return -EIO;
28 }
29 
30 static ssize_t bad_file_write(struct file *filp, const char __user *buf,
31 			size_t siz, loff_t *ppos)
32 {
33         return -EIO;
34 }
35 
36 static ssize_t bad_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
37 			unsigned long nr_segs, loff_t pos)
38 {
39 	return -EIO;
40 }
41 
42 static ssize_t bad_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
43 			unsigned long nr_segs, loff_t pos)
44 {
45 	return -EIO;
46 }
47 
48 static int bad_file_readdir(struct file *filp, void *dirent, filldir_t filldir)
49 {
50 	return -EIO;
51 }
52 
53 static unsigned int bad_file_poll(struct file *filp, poll_table *wait)
54 {
55 	return POLLERR;
56 }
57 
58 static long bad_file_unlocked_ioctl(struct file *file, unsigned cmd,
59 			unsigned long arg)
60 {
61 	return -EIO;
62 }
63 
64 static long bad_file_compat_ioctl(struct file *file, unsigned int cmd,
65 			unsigned long arg)
66 {
67 	return -EIO;
68 }
69 
70 static int bad_file_mmap(struct file *file, struct vm_area_struct *vma)
71 {
72 	return -EIO;
73 }
74 
75 static int bad_file_open(struct inode *inode, struct file *filp)
76 {
77 	return -EIO;
78 }
79 
80 static int bad_file_flush(struct file *file, fl_owner_t id)
81 {
82 	return -EIO;
83 }
84 
85 static int bad_file_release(struct inode *inode, struct file *filp)
86 {
87 	return -EIO;
88 }
89 
90 static int bad_file_fsync(struct file *file, int datasync)
91 {
92 	return -EIO;
93 }
94 
95 static int bad_file_aio_fsync(struct kiocb *iocb, int datasync)
96 {
97 	return -EIO;
98 }
99 
100 static int bad_file_fasync(int fd, struct file *filp, int on)
101 {
102 	return -EIO;
103 }
104 
105 static int bad_file_lock(struct file *file, int cmd, struct file_lock *fl)
106 {
107 	return -EIO;
108 }
109 
110 static ssize_t bad_file_sendpage(struct file *file, struct page *page,
111 			int off, size_t len, loff_t *pos, int more)
112 {
113 	return -EIO;
114 }
115 
116 static unsigned long bad_file_get_unmapped_area(struct file *file,
117 				unsigned long addr, unsigned long len,
118 				unsigned long pgoff, unsigned long flags)
119 {
120 	return -EIO;
121 }
122 
123 static int bad_file_check_flags(int flags)
124 {
125 	return -EIO;
126 }
127 
128 static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl)
129 {
130 	return -EIO;
131 }
132 
133 static ssize_t bad_file_splice_write(struct pipe_inode_info *pipe,
134 			struct file *out, loff_t *ppos, size_t len,
135 			unsigned int flags)
136 {
137 	return -EIO;
138 }
139 
140 static ssize_t bad_file_splice_read(struct file *in, loff_t *ppos,
141 			struct pipe_inode_info *pipe, size_t len,
142 			unsigned int flags)
143 {
144 	return -EIO;
145 }
146 
147 static const struct file_operations bad_file_ops =
148 {
149 	.llseek		= bad_file_llseek,
150 	.read		= bad_file_read,
151 	.write		= bad_file_write,
152 	.aio_read	= bad_file_aio_read,
153 	.aio_write	= bad_file_aio_write,
154 	.readdir	= bad_file_readdir,
155 	.poll		= bad_file_poll,
156 	.unlocked_ioctl	= bad_file_unlocked_ioctl,
157 	.compat_ioctl	= bad_file_compat_ioctl,
158 	.mmap		= bad_file_mmap,
159 	.open		= bad_file_open,
160 	.flush		= bad_file_flush,
161 	.release	= bad_file_release,
162 	.fsync		= bad_file_fsync,
163 	.aio_fsync	= bad_file_aio_fsync,
164 	.fasync		= bad_file_fasync,
165 	.lock		= bad_file_lock,
166 	.sendpage	= bad_file_sendpage,
167 	.get_unmapped_area = bad_file_get_unmapped_area,
168 	.check_flags	= bad_file_check_flags,
169 	.flock		= bad_file_flock,
170 	.splice_write	= bad_file_splice_write,
171 	.splice_read	= bad_file_splice_read,
172 };
173 
174 static int bad_inode_create (struct inode *dir, struct dentry *dentry,
175 		int mode, struct nameidata *nd)
176 {
177 	return -EIO;
178 }
179 
180 static struct dentry *bad_inode_lookup(struct inode *dir,
181 			struct dentry *dentry, struct nameidata *nd)
182 {
183 	return ERR_PTR(-EIO);
184 }
185 
186 static int bad_inode_link (struct dentry *old_dentry, struct inode *dir,
187 		struct dentry *dentry)
188 {
189 	return -EIO;
190 }
191 
192 static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
193 {
194 	return -EIO;
195 }
196 
197 static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
198 		const char *symname)
199 {
200 	return -EIO;
201 }
202 
203 static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
204 			int mode)
205 {
206 	return -EIO;
207 }
208 
209 static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
210 {
211 	return -EIO;
212 }
213 
214 static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
215 			int mode, dev_t rdev)
216 {
217 	return -EIO;
218 }
219 
220 static int bad_inode_rename (struct inode *old_dir, struct dentry *old_dentry,
221 		struct inode *new_dir, struct dentry *new_dentry)
222 {
223 	return -EIO;
224 }
225 
226 static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
227 		int buflen)
228 {
229 	return -EIO;
230 }
231 
232 static int bad_inode_permission(struct inode *inode, int mask, unsigned int flags)
233 {
234 	if (flags & IPERM_FLAG_RCU)
235 		return -ECHILD;
236 
237 	return -EIO;
238 }
239 
240 static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
241 			struct kstat *stat)
242 {
243 	return -EIO;
244 }
245 
246 static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
247 {
248 	return -EIO;
249 }
250 
251 static int bad_inode_setxattr(struct dentry *dentry, const char *name,
252 		const void *value, size_t size, int flags)
253 {
254 	return -EIO;
255 }
256 
257 static ssize_t bad_inode_getxattr(struct dentry *dentry, const char *name,
258 			void *buffer, size_t size)
259 {
260 	return -EIO;
261 }
262 
263 static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer,
264 			size_t buffer_size)
265 {
266 	return -EIO;
267 }
268 
269 static int bad_inode_removexattr(struct dentry *dentry, const char *name)
270 {
271 	return -EIO;
272 }
273 
274 static const struct inode_operations bad_inode_ops =
275 {
276 	.create		= bad_inode_create,
277 	.lookup		= bad_inode_lookup,
278 	.link		= bad_inode_link,
279 	.unlink		= bad_inode_unlink,
280 	.symlink	= bad_inode_symlink,
281 	.mkdir		= bad_inode_mkdir,
282 	.rmdir		= bad_inode_rmdir,
283 	.mknod		= bad_inode_mknod,
284 	.rename		= bad_inode_rename,
285 	.readlink	= bad_inode_readlink,
286 	/* follow_link must be no-op, otherwise unmounting this inode
287 	   won't work */
288 	/* put_link returns void */
289 	/* truncate returns void */
290 	.permission	= bad_inode_permission,
291 	.getattr	= bad_inode_getattr,
292 	.setattr	= bad_inode_setattr,
293 	.setxattr	= bad_inode_setxattr,
294 	.getxattr	= bad_inode_getxattr,
295 	.listxattr	= bad_inode_listxattr,
296 	.removexattr	= bad_inode_removexattr,
297 	/* truncate_range returns void */
298 };
299 
300 
301 /*
302  * When a filesystem is unable to read an inode due to an I/O error in
303  * its read_inode() function, it can call make_bad_inode() to return a
304  * set of stubs which will return EIO errors as required.
305  *
306  * We only need to do limited initialisation: all other fields are
307  * preinitialised to zero automatically.
308  */
309 
310 /**
311  *	make_bad_inode - mark an inode bad due to an I/O error
312  *	@inode: Inode to mark bad
313  *
314  *	When an inode cannot be read due to a media or remote network
315  *	failure this function makes the inode "bad" and causes I/O operations
316  *	on it to fail from this point on.
317  */
318 
319 void make_bad_inode(struct inode *inode)
320 {
321 	remove_inode_hash(inode);
322 
323 	inode->i_mode = S_IFREG;
324 	inode->i_atime = inode->i_mtime = inode->i_ctime =
325 		current_fs_time(inode->i_sb);
326 	inode->i_op = &bad_inode_ops;
327 	inode->i_fop = &bad_file_ops;
328 }
329 EXPORT_SYMBOL(make_bad_inode);
330 
331 /*
332  * This tests whether an inode has been flagged as bad. The test uses
333  * &bad_inode_ops to cover the case of invalidated inodes as well as
334  * those created by make_bad_inode() above.
335  */
336 
337 /**
338  *	is_bad_inode - is an inode errored
339  *	@inode: inode to test
340  *
341  *	Returns true if the inode in question has been marked as bad.
342  */
343 
344 int is_bad_inode(struct inode *inode)
345 {
346 	return (inode->i_op == &bad_inode_ops);
347 }
348 
349 EXPORT_SYMBOL(is_bad_inode);
350 
351 /**
352  * iget_failed - Mark an under-construction inode as dead and release it
353  * @inode: The inode to discard
354  *
355  * Mark an under-construction inode as dead and release it.
356  */
357 void iget_failed(struct inode *inode)
358 {
359 	make_bad_inode(inode);
360 	unlock_new_inode(inode);
361 	iput(inode);
362 }
363 EXPORT_SYMBOL(iget_failed);
364