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 long bad_file_unlocked_ioctl(struct file *file, unsigned cmd,
59			unsigned long arg)
60{
61	return -EIO;
62}
63
64static long bad_file_compat_ioctl(struct file *file, unsigned int cmd,
65			unsigned long arg)
66{
67	return -EIO;
68}
69
70static int bad_file_mmap(struct file *file, struct vm_area_struct *vma)
71{
72	return -EIO;
73}
74
75static int bad_file_open(struct inode *inode, struct file *filp)
76{
77	return -EIO;
78}
79
80static int bad_file_flush(struct file *file, fl_owner_t id)
81{
82	return -EIO;
83}
84
85static int bad_file_release(struct inode *inode, struct file *filp)
86{
87	return -EIO;
88}
89
90static int bad_file_fsync(struct file *file, int datasync)
91{
92	return -EIO;
93}
94
95static int bad_file_aio_fsync(struct kiocb *iocb, int datasync)
96{
97	return -EIO;
98}
99
100static int bad_file_fasync(int fd, struct file *filp, int on)
101{
102	return -EIO;
103}
104
105static int bad_file_lock(struct file *file, int cmd, struct file_lock *fl)
106{
107	return -EIO;
108}
109
110static 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
116static 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
123static int bad_file_check_flags(int flags)
124{
125	return -EIO;
126}
127
128static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl)
129{
130	return -EIO;
131}
132
133static 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
140static 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
147static 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
174static int bad_inode_create (struct inode *dir, struct dentry *dentry,
175		int mode, struct nameidata *nd)
176{
177	return -EIO;
178}
179
180static struct dentry *bad_inode_lookup(struct inode *dir,
181			struct dentry *dentry, struct nameidata *nd)
182{
183	return ERR_PTR(-EIO);
184}
185
186static int bad_inode_link (struct dentry *old_dentry, struct inode *dir,
187		struct dentry *dentry)
188{
189	return -EIO;
190}
191
192static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
193{
194	return -EIO;
195}
196
197static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
198		const char *symname)
199{
200	return -EIO;
201}
202
203static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
204			int mode)
205{
206	return -EIO;
207}
208
209static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
210{
211	return -EIO;
212}
213
214static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
215			int mode, dev_t rdev)
216{
217	return -EIO;
218}
219
220static 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
226static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
227		int buflen)
228{
229	return -EIO;
230}
231
232static int bad_inode_permission(struct inode *inode, int mask)
233{
234	return -EIO;
235}
236
237static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
238			struct kstat *stat)
239{
240	return -EIO;
241}
242
243static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
244{
245	return -EIO;
246}
247
248static int bad_inode_setxattr(struct dentry *dentry, const char *name,
249		const void *value, size_t size, int flags)
250{
251	return -EIO;
252}
253
254static ssize_t bad_inode_getxattr(struct dentry *dentry, const char *name,
255			void *buffer, size_t size)
256{
257	return -EIO;
258}
259
260static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer,
261			size_t buffer_size)
262{
263	return -EIO;
264}
265
266static int bad_inode_removexattr(struct dentry *dentry, const char *name)
267{
268	return -EIO;
269}
270
271static const struct inode_operations bad_inode_ops =
272{
273	.create		= bad_inode_create,
274	.lookup		= bad_inode_lookup,
275	.link		= bad_inode_link,
276	.unlink		= bad_inode_unlink,
277	.symlink	= bad_inode_symlink,
278	.mkdir		= bad_inode_mkdir,
279	.rmdir		= bad_inode_rmdir,
280	.mknod		= bad_inode_mknod,
281	.rename		= bad_inode_rename,
282	.readlink	= bad_inode_readlink,
283	/* follow_link must be no-op, otherwise unmounting this inode
284	   won't work */
285	/* put_link returns void */
286	/* truncate returns void */
287	.permission	= bad_inode_permission,
288	.getattr	= bad_inode_getattr,
289	.setattr	= bad_inode_setattr,
290	.setxattr	= bad_inode_setxattr,
291	.getxattr	= bad_inode_getxattr,
292	.listxattr	= bad_inode_listxattr,
293	.removexattr	= bad_inode_removexattr,
294	/* truncate_range returns void */
295};
296
297
298/*
299 * When a filesystem is unable to read an inode due to an I/O error in
300 * its read_inode() function, it can call make_bad_inode() to return a
301 * set of stubs which will return EIO errors as required.
302 *
303 * We only need to do limited initialisation: all other fields are
304 * preinitialised to zero automatically.
305 */
306
307/**
308 *	make_bad_inode - mark an inode bad due to an I/O error
309 *	@inode: Inode to mark bad
310 *
311 *	When an inode cannot be read due to a media or remote network
312 *	failure this function makes the inode "bad" and causes I/O operations
313 *	on it to fail from this point on.
314 */
315
316void make_bad_inode(struct inode *inode)
317{
318	remove_inode_hash(inode);
319
320	inode->i_mode = S_IFREG;
321	inode->i_atime = inode->i_mtime = inode->i_ctime =
322		current_fs_time(inode->i_sb);
323	inode->i_op = &bad_inode_ops;
324	inode->i_fop = &bad_file_ops;
325}
326EXPORT_SYMBOL(make_bad_inode);
327
328/*
329 * This tests whether an inode has been flagged as bad. The test uses
330 * &bad_inode_ops to cover the case of invalidated inodes as well as
331 * those created by make_bad_inode() above.
332 */
333
334/**
335 *	is_bad_inode - is an inode errored
336 *	@inode: inode to test
337 *
338 *	Returns true if the inode in question has been marked as bad.
339 */
340
341int is_bad_inode(struct inode *inode)
342{
343	return (inode->i_op == &bad_inode_ops);
344}
345
346EXPORT_SYMBOL(is_bad_inode);
347
348/**
349 * iget_failed - Mark an under-construction inode as dead and release it
350 * @inode: The inode to discard
351 *
352 * Mark an under-construction inode as dead and release it.
353 */
354void iget_failed(struct inode *inode)
355{
356	make_bad_inode(inode);
357	unlock_new_inode(inode);
358	iput(inode);
359}
360EXPORT_SYMBOL(iget_failed);
361