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
19static loff_t bad_file_llseek(struct file *file, loff_t offset, int origin)
20{
21	return -EIO;
22}
23
24static ssize_t bad_file_read(struct file *filp, char __user *buf,
25			size_t size, loff_t *ppos)
26{
27        return -EIO;
28}
29
30static 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
36static 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
42static 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
48static int bad_file_readdir(struct file *filp, void *dirent, filldir_t filldir)
49{
50	return -EIO;
51}
52
53static unsigned int bad_file_poll(struct file *filp, poll_table *wait)
54{
55	return POLLERR;
56}
57
58static int bad_file_ioctl (struct inode *inode, struct file *filp,
59			unsigned int cmd, unsigned long arg)
60{
61	return -EIO;
62}
63
64static long bad_file_unlocked_ioctl(struct file *file, unsigned cmd,
65			unsigned long arg)
66{
67	return -EIO;
68}
69
70static long bad_file_compat_ioctl(struct file *file, unsigned int cmd,
71			unsigned long arg)
72{
73	return -EIO;
74}
75
76static int bad_file_mmap(struct file *file, struct vm_area_struct *vma)
77{
78	return -EIO;
79}
80
81static int bad_file_open(struct inode *inode, struct file *filp)
82{
83	return -EIO;
84}
85
86static int bad_file_flush(struct file *file, fl_owner_t id)
87{
88	return -EIO;
89}
90
91static int bad_file_release(struct inode *inode, struct file *filp)
92{
93	return -EIO;
94}
95
96static int bad_file_fsync(struct file *file, struct dentry *dentry,
97			int datasync)
98{
99	return -EIO;
100}
101
102static int bad_file_aio_fsync(struct kiocb *iocb, int datasync)
103{
104	return -EIO;
105}
106
107static int bad_file_fasync(int fd, struct file *filp, int on)
108{
109	return -EIO;
110}
111
112static int bad_file_lock(struct file *file, int cmd, struct file_lock *fl)
113{
114	return -EIO;
115}
116
117static ssize_t bad_file_sendfile(struct file *in_file, loff_t *ppos,
118			size_t count, read_actor_t actor, void *target)
119{
120	return -EIO;
121}
122
123static ssize_t bad_file_sendpage(struct file *file, struct page *page,
124			int off, size_t len, loff_t *pos, int more)
125{
126	return -EIO;
127}
128
129static unsigned long bad_file_get_unmapped_area(struct file *file,
130				unsigned long addr, unsigned long len,
131				unsigned long pgoff, unsigned long flags)
132{
133	return -EIO;
134}
135
136static int bad_file_check_flags(int flags)
137{
138	return -EIO;
139}
140
141static int bad_file_dir_notify(struct file *file, unsigned long arg)
142{
143	return -EIO;
144}
145
146static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl)
147{
148	return -EIO;
149}
150
151static ssize_t bad_file_splice_write(struct pipe_inode_info *pipe,
152			struct file *out, loff_t *ppos, size_t len,
153			unsigned int flags)
154{
155	return -EIO;
156}
157
158static ssize_t bad_file_splice_read(struct file *in, loff_t *ppos,
159			struct pipe_inode_info *pipe, size_t len,
160			unsigned int flags)
161{
162	return -EIO;
163}
164
165static const struct file_operations bad_file_ops =
166{
167	.llseek		= bad_file_llseek,
168	.read		= bad_file_read,
169	.write		= bad_file_write,
170	.aio_read	= bad_file_aio_read,
171	.aio_write	= bad_file_aio_write,
172	.readdir	= bad_file_readdir,
173	.poll		= bad_file_poll,
174	.ioctl		= bad_file_ioctl,
175	.unlocked_ioctl	= bad_file_unlocked_ioctl,
176	.compat_ioctl	= bad_file_compat_ioctl,
177	.mmap		= bad_file_mmap,
178	.open		= bad_file_open,
179	.flush		= bad_file_flush,
180	.release	= bad_file_release,
181	.fsync		= bad_file_fsync,
182	.aio_fsync	= bad_file_aio_fsync,
183	.fasync		= bad_file_fasync,
184	.lock		= bad_file_lock,
185	.sendfile	= bad_file_sendfile,
186	.sendpage	= bad_file_sendpage,
187	.get_unmapped_area = bad_file_get_unmapped_area,
188	.check_flags	= bad_file_check_flags,
189	.dir_notify	= bad_file_dir_notify,
190	.flock		= bad_file_flock,
191	.splice_write	= bad_file_splice_write,
192	.splice_read	= bad_file_splice_read,
193};
194
195static int bad_inode_create (struct inode *dir, struct dentry *dentry,
196		int mode, struct nameidata *nd)
197{
198	return -EIO;
199}
200
201static struct dentry *bad_inode_lookup(struct inode *dir,
202			struct dentry *dentry, struct nameidata *nd)
203{
204	return ERR_PTR(-EIO);
205}
206
207static int bad_inode_link (struct dentry *old_dentry, struct inode *dir,
208		struct dentry *dentry)
209{
210	return -EIO;
211}
212
213static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
214{
215	return -EIO;
216}
217
218static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
219		const char *symname)
220{
221	return -EIO;
222}
223
224static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
225			int mode)
226{
227	return -EIO;
228}
229
230static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
231{
232	return -EIO;
233}
234
235static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
236			int mode, dev_t rdev)
237{
238	return -EIO;
239}
240
241static int bad_inode_rename (struct inode *old_dir, struct dentry *old_dentry,
242		struct inode *new_dir, struct dentry *new_dentry)
243{
244	return -EIO;
245}
246
247static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
248		int buflen)
249{
250	return -EIO;
251}
252
253static int bad_inode_permission(struct inode *inode, int mask,
254			struct nameidata *nd)
255{
256	return -EIO;
257}
258
259static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
260			struct kstat *stat)
261{
262	return -EIO;
263}
264
265static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
266{
267	return -EIO;
268}
269
270static int bad_inode_setxattr(struct dentry *dentry, const char *name,
271		const void *value, size_t size, int flags)
272{
273	return -EIO;
274}
275
276static ssize_t bad_inode_getxattr(struct dentry *dentry, const char *name,
277			void *buffer, size_t size)
278{
279	return -EIO;
280}
281
282static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer,
283			size_t buffer_size)
284{
285	return -EIO;
286}
287
288static int bad_inode_removexattr(struct dentry *dentry, const char *name)
289{
290	return -EIO;
291}
292
293static const struct inode_operations bad_inode_ops =
294{
295	.create		= bad_inode_create,
296	.lookup		= bad_inode_lookup,
297	.link		= bad_inode_link,
298	.unlink		= bad_inode_unlink,
299	.symlink	= bad_inode_symlink,
300	.mkdir		= bad_inode_mkdir,
301	.rmdir		= bad_inode_rmdir,
302	.mknod		= bad_inode_mknod,
303	.rename		= bad_inode_rename,
304	.readlink	= bad_inode_readlink,
305	/* follow_link must be no-op, otherwise unmounting this inode
306	   won't work */
307	/* put_link returns void */
308	/* truncate returns void */
309	.permission	= bad_inode_permission,
310	.getattr	= bad_inode_getattr,
311	.setattr	= bad_inode_setattr,
312	.setxattr	= bad_inode_setxattr,
313	.getxattr	= bad_inode_getxattr,
314	.listxattr	= bad_inode_listxattr,
315	.removexattr	= bad_inode_removexattr,
316	/* truncate_range returns void */
317};
318
319
320/*
321 * When a filesystem is unable to read an inode due to an I/O error in
322 * its read_inode() function, it can call make_bad_inode() to return a
323 * set of stubs which will return EIO errors as required.
324 *
325 * We only need to do limited initialisation: all other fields are
326 * preinitialised to zero automatically.
327 */
328
329/**
330 *	make_bad_inode - mark an inode bad due to an I/O error
331 *	@inode: Inode to mark bad
332 *
333 *	When an inode cannot be read due to a media or remote network
334 *	failure this function makes the inode "bad" and causes I/O operations
335 *	on it to fail from this point on.
336 */
337
338void make_bad_inode(struct inode *inode)
339{
340	remove_inode_hash(inode);
341
342	inode->i_mode = S_IFREG;
343	inode->i_atime = inode->i_mtime = inode->i_ctime =
344		current_fs_time(inode->i_sb);
345	inode->i_op = &bad_inode_ops;
346	inode->i_fop = &bad_file_ops;
347}
348EXPORT_SYMBOL(make_bad_inode);
349
350/*
351 * This tests whether an inode has been flagged as bad. The test uses
352 * &bad_inode_ops to cover the case of invalidated inodes as well as
353 * those created by make_bad_inode() above.
354 */
355
356/**
357 *	is_bad_inode - is an inode errored
358 *	@inode: inode to test
359 *
360 *	Returns true if the inode in question has been marked as bad.
361 */
362
363int is_bad_inode(struct inode *inode)
364{
365	return (inode->i_op == &bad_inode_ops);
366}
367
368EXPORT_SYMBOL(is_bad_inode);
369