Root/fs/bad_inode.c

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

Archive Download this file



interactive