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/smp_lock.h>
  16 #include <linux/namei.h>
  17 #include <linux/poll.h>
  18
  19
  20 static loff_t bad_file_llseek(struct file *file, loff_t offset, int origin)
  21 {
  22         return -EIO;
  23 }
  24
  25 static ssize_t bad_file_read(struct file *filp, char __user *buf,
  26                         size_t size, loff_t *ppos)
  27 {
  28         return -EIO;
  29 }
  30
  31 static ssize_t bad_file_write(struct file *filp, const char __user *buf,
  32                         size_t siz, loff_t *ppos)
  33 {
  34         return -EIO;
  35 }
  36
  37 static ssize_t bad_file_aio_read(struct kiocb *iocb, char __user *buf,
  38                         size_t siz, loff_t pos)
  39 {
  40         return -EIO;
  41 }
  42
  43 static ssize_t bad_file_aio_write(struct kiocb *iocb, const char __user *buf,
  44                         size_t siz, loff_t pos)
  45 {
  46         return -EIO;
  47 }
  48
  49 static int bad_file_readdir(struct file *filp, void *dirent, filldir_t filldir)
  50 {
  51         return -EIO;
  52 }
  53
  54 static unsigned int bad_file_poll(struct file *filp, poll_table *wait)
  55 {
  56         return POLLERR;
  57 }
  58
  59 static int bad_file_ioctl (struct inode *inode, struct file *filp,
  60                         unsigned int cmd, unsigned long arg)
  61 {
  62         return -EIO;
  63 }
  64
  65 static long bad_file_unlocked_ioctl(struct file *file, unsigned cmd,
  66                         unsigned long arg)
  67 {
  68         return -EIO;
  69 }
  70
  71 static long bad_file_compat_ioctl(struct file *file, unsigned int cmd,
  72                         unsigned long arg)
  73 {
  74         return -EIO;
  75 }
  76
  77 static int bad_file_mmap(struct file *file, struct vm_area_struct *vma)
  78 {
  79         return -EIO;
  80 }
  81
  82 static int bad_file_open(struct inode *inode, struct file *filp)
  83 {
  84         return -EIO;
  85 }
  86
  87 static int bad_file_flush(struct file *file)
  88 {
  89         return -EIO;
  90 }
  91
  92 static int bad_file_release(struct inode *inode, struct file *filp)
  93 {
  94         return -EIO;
  95 }
  96
  97 static int bad_file_fsync(struct file *file, struct dentry *dentry,
  98                         int datasync)
  99 {
 100         return -EIO;
 101 }
 102
 103 static int bad_file_aio_fsync(struct kiocb *iocb, int datasync)
 104 {
 105         return -EIO;
 106 }
 107
 108 static int bad_file_fasync(int fd, struct file *filp, int on)
 109 {
 110         return -EIO;
 111 }
 112
 113 static int bad_file_lock(struct file *file, int cmd, struct file_lock *fl)
 114 {
 115         return -EIO;
 116 }
 117
 118 static ssize_t bad_file_readv(struct file *file, const struct iovec *iv,
 119                               unsigned long count, loff_t *pos)
 120 {
 121         return -EIO;
 122 }
 123
 124 static ssize_t bad_file_writev(struct file *file, const struct iovec *iv,
 125                                unsigned long count, loff_t *pos)
 126 {
 127         return -EIO;
 128 }
 129
 130 static ssize_t bad_file_sendfile(struct file *in_file, loff_t *ppos,
 131                         size_t count, read_actor_t actor, void *target)
 132 {
 133         return -EIO;
 134 }
 135
 136 static ssize_t bad_file_sendpage(struct file *file, struct page *page,
 137                         int off, size_t len, loff_t *pos, int more)
 138 {
 139         return -EIO;
 140 }
 141
 142 static unsigned long bad_file_get_unmapped_area(struct file *file,
 143                                 unsigned long addr, unsigned long len,
 144                                 unsigned long pgoff, unsigned long flags)
 145 {
 146         return -EIO;
 147 }
 148
 149 static int bad_file_check_flags(int flags)
 150 {
 151         return -EIO;
 152 }
 153
 154 static int bad_file_dir_notify(struct file *file, unsigned long arg)
 155 {
 156         return -EIO;
 157 }
 158
 159 static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl)
 160 {
 161         return -EIO;
 162 }
 163
 164 static struct file_operations bad_file_ops =
 165 {
 166         .llseek         = bad_file_llseek,
 167         .read           = bad_file_read,
 168         .write          = bad_file_write,
 169         .aio_read       = bad_file_aio_read,
 170         .aio_write      = bad_file_aio_write,
 171         .readdir        = bad_file_readdir,
 172         .poll           = bad_file_poll,
 173         .ioctl          = bad_file_ioctl,
 174         .unlocked_ioctl = bad_file_unlocked_ioctl,
 175         .compat_ioctl   = bad_file_compat_ioctl,
 176         .mmap           = bad_file_mmap,
 177         .open           = bad_file_open,
 178         .flush          = bad_file_flush,
 179         .release        = bad_file_release,
 180         .fsync          = bad_file_fsync,
 181         .aio_fsync      = bad_file_aio_fsync,
 182         .fasync         = bad_file_fasync,
 183         .lock           = bad_file_lock,
 184         .readv          = bad_file_readv,
 185         .writev         = bad_file_writev,
 186         .sendfile       = bad_file_sendfile,
 187         .sendpage       = bad_file_sendpage,
 188         .get_unmapped_area = bad_file_get_unmapped_area,
 189         .check_flags    = bad_file_check_flags,
 190         .dir_notify     = bad_file_dir_notify,
 191         .flock          = bad_file_flock,
 192 };
 193
 194 static int bad_inode_create (struct inode *dir, struct dentry *dentry,
 195                 int mode, struct nameidata *nd)
 196 {
 197         return -EIO;
 198 }
 199
 200 static struct dentry *bad_inode_lookup(struct inode *dir,
 201                         struct dentry *dentry, struct nameidata *nd)
 202 {
 203         return ERR_PTR(-EIO);
 204 }
 205
 206 static int bad_inode_link (struct dentry *old_dentry, struct inode *dir,
 207                 struct dentry *dentry)
 208 {
 209         return -EIO;
 210 }
 211
 212 static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
 213 {
 214         return -EIO;
 215 }
 216
 217 static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
 218                 const char *symname)
 219 {
 220         return -EIO;
 221 }
 222
 223 static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
 224                         int mode)
 225 {
 226         return -EIO;
 227 }
 228
 229 static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
 230 {
 231         return -EIO;
 232 }
 233
 234 static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
 235                         int mode, dev_t rdev)
 236 {
 237         return -EIO;
 238 }
 239
 240 static int bad_inode_rename (struct inode *old_dir, struct dentry *old_dentry,
 241                 struct inode *new_dir, struct dentry *new_dentry)
 242 {
 243         return -EIO;
 244 }
 245
 246 static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
 247                 int buflen)
 248 {
 249         return -EIO;
 250 }
 251
 252 static int bad_inode_permission(struct inode *inode, int mask,
 253                         struct nameidata *nd)
 254 {
 255         return -EIO;
 256 }
 257
 258 static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
 259                         struct kstat *stat)
 260 {
 261         return -EIO;
 262 }
 263
 264 static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
 265 {
 266         return -EIO;
 267 }
 268
 269 static int bad_inode_setxattr(struct dentry *dentry, const char *name,
 270                 const void *value, size_t size, int flags)
 271 {
 272         return -EIO;
 273 }
 274
 275 static ssize_t bad_inode_getxattr(struct dentry *dentry, const char *name,
 276                         void *buffer, size_t size)
 277 {
 278         return -EIO;
 279 }
 280
 281 static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer,
 282                         size_t buffer_size)
 283 {
 284         return -EIO;
 285 }
 286
 287 static int bad_inode_removexattr(struct dentry *dentry, const char *name)
 288 {
 289         return -EIO;
 290 }
 291
 292 static struct inode_operations bad_inode_ops =
 293 {
 294         .create         = bad_inode_create,
 295         .lookup         = bad_inode_lookup,
 296         .link           = bad_inode_link,
 297         .unlink         = bad_inode_unlink,
 298         .symlink        = bad_inode_symlink,
 299         .mkdir          = bad_inode_mkdir,
 300         .rmdir          = bad_inode_rmdir,
 301         .mknod          = bad_inode_mknod,
 302         .rename         = bad_inode_rename,
 303         .readlink       = bad_inode_readlink,
 304         /* follow_link must be no-op, otherwise unmounting this inode
 305            won't work */
 306         /* put_link returns void */
 307         /* truncate returns void */
 308         .permission     = bad_inode_permission,
 309         .getattr        = bad_inode_getattr,
 310         .setattr        = bad_inode_setattr,
 311         .setxattr       = bad_inode_setxattr,
 312         .getxattr       = bad_inode_getxattr,
 313         .listxattr      = bad_inode_listxattr,
 314         .removexattr    = bad_inode_removexattr,
 315         /* truncate_range returns void */
 316 };
 317
 318
 319 /*
 320  * When a filesystem is unable to read an inode due to an I/O error in
 321  * its read_inode() function, it can call make_bad_inode() to return a
 322  * set of stubs which will return EIO errors as required.
 323  *
 324  * We only need to do limited initialisation: all other fields are
 325  * preinitialised to zero automatically.
 326  */
 327
 328 /**
 329  *      make_bad_inode - mark an inode bad due to an I/O error
 330  *      @inode: Inode to mark bad
 331  *
 332  *      When an inode cannot be read due to a media or remote network
 333  *      failure this function makes the inode "bad" and causes I/O operations
 334  *      on it to fail from this point on.
 335  */
 336
 337 void make_bad_inode(struct inode *inode)
 338 {
 339         remove_inode_hash(inode);
 340
 341         inode->i_mode = S_IFREG;
 342         inode->i_atime = inode->i_mtime = inode->i_ctime =
 343                 current_fs_time(inode->i_sb);
 344         inode->i_op = &bad_inode_ops;
 345         inode->i_fop = &bad_file_ops;
 346 }
 347 EXPORT_SYMBOL(make_bad_inode);
 348
 349 /*
 350  * This tests whether an inode has been flagged as bad. The test uses
 351  * &bad_inode_ops to cover the case of invalidated inodes as well as
 352  * those created by make_bad_inode() above.
 353  */
 354
 355 /**
 356  *      is_bad_inode - is an inode errored
 357  *      @inode: inode to test
 358  *
 359  *      Returns true if the inode in question has been marked as bad.
 360  */
 361
 362 int is_bad_inode(struct inode *inode)
 363 {
 364         return (inode->i_op == &bad_inode_ops);
 365 }
 366
 367 EXPORT_SYMBOL(is_bad_inode);